Subjects -> BUILDING AND CONSTRUCTION (Total: 139 journals)
    - BUILDING AND CONSTRUCTION (131 journals)
    - CARPENTRY AND WOODWORK (8 journals)

BUILDING AND CONSTRUCTION (131 journals)                     

Showing 1 - 35 of 35 Journals sorted alphabetically
Advances in Building Energy Research     Hybrid Journal   (Followers: 11)
Asian Journal of Civil Engineering     Hybrid Journal   (Followers: 3)
Australasian Journal of Construction Economics and Building     Open Access   (Followers: 9)
Baltic Journal of Real Estate Economics and Construction Management     Open Access   (Followers: 4)
Bautechnik     Hybrid Journal   (Followers: 1)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 1)
Building Acoustics     Hybrid Journal   (Followers: 4)
Building Services Engineering Research & Technology     Hybrid Journal   (Followers: 3)
Buildings     Open Access   (Followers: 11)
BUILT : International Journal of Building, Urban, Interior and Landscape Technology     Open Access   (Followers: 3)
Built Environment Inquiry Journal     Open Access  
Built Environment Project and Asset Management     Hybrid Journal   (Followers: 13)
Case Studies in Construction Materials     Open Access   (Followers: 8)
Cement     Open Access   (Followers: 6)
Cement and Concrete Composites     Hybrid Journal   (Followers: 20)
Cement and Concrete Research     Hybrid Journal   (Followers: 20)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 5)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 4)
Change Over Time     Full-text available via subscription   (Followers: 3)
City, Culture and Society     Hybrid Journal   (Followers: 25)
Cityscape     Full-text available via subscription   (Followers: 10)
Clay Technology     Full-text available via subscription  
Construction Economics and Building     Open Access   (Followers: 4)
Construction Engineering     Open Access   (Followers: 9)
Construction Management and Economics     Hybrid Journal   (Followers: 24)
Construction Research and Innovation     Hybrid Journal   (Followers: 5)
Construction Robotics     Hybrid Journal   (Followers: 5)
Corporate Real Estate Journal     Full-text available via subscription   (Followers: 7)
Dams and Reservoirs     Hybrid Journal   (Followers: 4)
Developments in the Built Environment     Open Access   (Followers: 1)
Energy and Built Environment     Open Access  
Engineering Project Organization Journal     Hybrid Journal   (Followers: 6)
Engineering, Construction and Architectural Management     Hybrid Journal   (Followers: 14)
Environment and Urbanization Asia     Hybrid Journal   (Followers: 2)
Facilities     Hybrid Journal   (Followers: 7)
FUTY Journal of the Environment     Full-text available via subscription  
Glass Structures & Engineering     Hybrid Journal   (Followers: 1)
HBRC Journal     Open Access  
Housing and Society     Hybrid Journal   (Followers: 5)
HVAC&R Research     Hybrid Journal  
Indoor and Built Environment     Hybrid Journal   (Followers: 3)
Informes de la Construcción     Open Access  
Intelligent Buildings International     Hybrid Journal   (Followers: 2)
International Journal of Advanced Structural Engineering     Open Access   (Followers: 26)
International Journal of Architectural Computing     Full-text available via subscription   (Followers: 6)
International Journal of Built Environment and Sustainability     Open Access   (Followers: 3)
International Journal of Concrete Structures and Materials     Open Access   (Followers: 10)
International Journal of Construction Engineering and Management     Open Access   (Followers: 9)
International Journal of Construction Management     Hybrid Journal   (Followers: 4)
International Journal of Disaster Resilience in the Built Environment     Hybrid Journal   (Followers: 5)
International Journal of Housing Markets and Analysis     Hybrid Journal   (Followers: 11)
International Journal of Masonry Research and Innovation     Hybrid Journal  
International Journal of Protective Structures     Hybrid Journal   (Followers: 6)
International Journal of River Basin Management     Hybrid Journal   (Followers: 1)
International Journal of Structural Stability and Dynamics     Hybrid Journal   (Followers: 9)
International Journal of Sustainable Building Technology and Urban Development     Hybrid Journal   (Followers: 14)
International Journal of Sustainable Construction Engineering and Technology     Open Access   (Followers: 8)
International Journal of Sustainable Real Estate and Construction Economics     Hybrid Journal   (Followers: 2)
International Journal of the Built Environment and Asset Management     Hybrid Journal   (Followers: 5)
International Journal of Ventilation     Full-text available via subscription  
Journal for Education in the Built Environment     Open Access   (Followers: 4)
Journal of Aging and Environment     Hybrid Journal   (Followers: 4)
Journal of Architecture, Planning and Construction Management     Open Access   (Followers: 12)
Journal of Asian Architecture and Building Engineering     Open Access  
Journal of Building Construction and Planning Research     Open Access   (Followers: 10)
Journal of Building Engineering     Hybrid Journal   (Followers: 5)
Journal of Building Pathology and Rehabilitation     Hybrid Journal  
Journal of Building Performance Simulation     Hybrid Journal   (Followers: 6)
Journal of Civil Engineering and Construction Technology     Open Access   (Followers: 14)
Journal of Civil Engineering and Management     Open Access   (Followers: 9)
Journal of Computing in Civil Engineering     Full-text available via subscription   (Followers: 23)
Journal of Construction Business and Management     Open Access   (Followers: 2)
Journal of Facilities Management     Hybrid Journal   (Followers: 4)
Journal of Legal Affairs and Dispute Resolution in Engineering and Construction     Full-text available via subscription   (Followers: 4)
Journal of Property, Planning and Environmental Law     Hybrid Journal   (Followers: 8)
Journal of Structural Fire Engineering     Full-text available via subscription   (Followers: 4)
Journal of Sustainable Cement-Based Materials     Hybrid Journal  
Journal of Transport and Land Use     Open Access   (Followers: 30)
Journal of Urban Technology and Sustainability     Open Access   (Followers: 3)
Landscape History     Hybrid Journal   (Followers: 18)
Materiales de Construcción     Open Access   (Followers: 1)
Mauerwerk     Hybrid Journal  
Modular and Offsite Construction (MOC) Summit Proceedings |     Open Access  
Naval Engineers Journal     Hybrid Journal   (Followers: 1)
Nordic Concrete Research     Open Access  
Open Construction & Building Technology Journal     Open Access  
Proceedings of the Institution of Civil Engineers - Forensic Engineering     Hybrid Journal  
Proceedings of the Institution of Civil Engineers - Urban Design and Planning     Hybrid Journal   (Followers: 11)
Revista de la Construcción     Open Access  
Revista de Urbanismo     Open Access   (Followers: 2)
Revista Ingenieria de Construcción     Open Access   (Followers: 1)
Revista INVI     Open Access  
Room One Thousand     Open Access  
Russian Journal of Construction Science and Technology     Open Access  
Science and Technology for the Built Environment     Hybrid Journal  
Smart and Sustainable Built Environment     Hybrid Journal   (Followers: 9)
Steel Construction - Design and Research     Hybrid Journal   (Followers: 4)
Structural Concrete     Hybrid Journal   (Followers: 5)
Structural Mechanics of Engineering Constructions and Buildings     Open Access   (Followers: 3)
Sustainable Buildings     Open Access   (Followers: 3)
Sustainable Cities and Society     Hybrid Journal   (Followers: 23)
Technology|Architecture + Design     Hybrid Journal  
The Historic Environment : Policy & Practice     Hybrid Journal   (Followers: 4)
The IES Journal Part A: Civil & Structural Engineering     Hybrid Journal   (Followers: 5)
The Journal of Integrated Security and Safety Science (JISSS)     Open Access   (Followers: 3)
Tidsskrift for boligforskning     Open Access  

           

Similar Journals
Journal Cover
International Journal of Structural Stability and Dynamics
Journal Prestige (SJR): 1.005
Citation Impact (citeScore): 2
Number of Followers: 9  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0219-4554 - ISSN (Online) 1793-6764
Published by World Scientific Homepage  [121 journals]
  • Spectral Analysis of a Sagged Cable with an Optimal
           Viscous Inertial Mass Damper under Random Wind in a Generalized
           State-Space Formulation

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      Authors: Y. F. Duan, N. Deng, Y. X. Rao, S. H. Dong, C. B. Yun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a spectral analysis method is proposed for a sagged cable with an optimal viscous inertial mass damper (VIMD) under random wind loads based on a generalized state-space formulation. The frequency response functions of the cable responses were evaluated for the wind force vector using complex modes orthogonal to the system matrices, from which the power spectral densities of the cable responses were readily obtained for the spectral matrix of the wind force. The accuracy and efficiency of the proposed method were verified by comparing the root mean square responses with those obtained from the time-domain and covariance analyses. The performance of two VIMDs optimized by the fixed-point method and the maximum damping ratio method was investigated for various cases of cable sag and wind properties. Serviceability failure probability analysis was also conducted using the first-passage problem. The results show that the proposed spectral method is computationally more efficient than the other two analysis methods. The VIMDs optimized for the first original cable mode were found to be highly effective in reducing cable vibration and the probability of serviceability failure.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-10T07:00:00Z
      DOI: 10.1142/S0219455425400061
       
  • Dynamic Response of Advanced Lightweight Porous Plates Integrated with
           Nanocomposite Face Sheets Resting on Elastic Substrate

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      Authors: Hossein Babaei, Saeid Zavari, Ali Kaveh, Ehsan Arshid, Ömer Civalek
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study centers on the analysis of a scale-dependent microplate configuration characterized by a porous core enveloped by nanocomposite patches embedded with graphene nanoplatelets. The microplate’s behavior is explored within a humid environment to comprehend the effects of moisture variations on its dynamic performance. Additionally, the microplate rests upon a Kerr foundation, a three-parameter elastic substrate. The material properties of all three layers are contingent upon thickness. To enhance precision, an innovative quasi-three-dimensional shear and normal trigonometric theory is employed, elucidating the kinematic interrelations of the microstructure. Notably, this novel theory accommodates the presence of transverse normal strain. For a comprehensive analysis of size influences, the modified couple stress theory is harnessed. This theory integrates a material length-scale parameter to anticipate outcomes at the micro-scale. By invoking Hamilton’s principle, differential motion equations are deduced and subsequently solved analytically. The investigation centers on probing the consequences of varied parameters on the natural frequencies. The findings underscore that the incorporation of GPLs amplifies the microplate’s stiffness, thus elevating its natural frequencies. In contrast, an escalation in the porosity index leads to a reduction in natural frequencies.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-10T07:00:00Z
      DOI: 10.1142/S0219455425501329
       
  • Investigation of the Penetration Capability of Exponential Bullets into
           Two Typical TPMS Lattice Structures

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      Authors: Bo Hao, Qi Jiang, Ziwen Zhang, Yuangen Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The TPMS lattice structure is widely utilized in the military UAV, and effectively striking the TPMS structure holds significant reference value in bullet design. This paper conducts a numerical simulation to study the penetration performance of exponential curve bullets with varying power exponents on the TPMS structures of Gyroid and Diamond. MATLAB is employed to design the TPMS lattice structure, and ABAQUS is used for numerical simulation. The results indicate that the velocity reduction rate of the bullet initially increases and then decreases with an increase in power exponent. Moreover, a larger power exponent leads to a smaller residual velocity and kinetic energy of the bullet. Different cell structures have a substantial impact on residual kinetic energy, with the Gyroid structure exhibiting significantly greater residual kinetic energy compared to the Diamond structure, resulting in an average kinetic energy difference of 15.429[math]J. The research shows that the curve of the arc part of the warhead has a great influence on the penetration performance. When designing the bullet used to hit the military UAV, the warhead with a large curvature change within a certain range can be considered.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-10T07:00:00Z
      DOI: 10.1142/S021945542550155X
       
  • Primary Resonances in Inclined Cantilever Beam with Tip-Mass: A
           Parameter-Splitting Multiple-Scales Approach

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      Authors: Hai-En Du, Chen-Yang Zhao, Yue Lin, Jia-Xin Zheng, Jian Ma, Chun-Long Huang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The transverse static load, resultant from self-weight, significantly impacts both the response and the nonlinear dynamic behavior of a flexible inclined cantilever with a large lumping tip mass under harmonic base motion. However, the transverse static load was not taken into account and the mode shape of a pure cantilever beam was directly adopted during Galerkin’s procedure in the formulations of a cantilever carrying a large lumping tip mass in many previous studies. In this paper, (1) the static load effect caused by the self-weight in an inclined cantilever is considered by using a coordinate transformation, (2) the efficacy of adopting a pure cantilever beam mode shape to analyze a cantilever beam carrying a large lumping mass is studied and (3) a recently proposed semi-analytical method named parameter-splitting multiple-scales method is extended to analyze the cantilever studied to examine its effectiveness. First, the extended Hamilton’s principle is utilized to formulate the equation of motion of the cantilever studied. After that, the mode shape of a pure cantilever and the exact mode shape of a cantilever carrying a lumping mass are separately adopted in Galerkin’s method to transform the partial differential equation into ordinary differential equations. The frequency-response curves of the discretized nonlinear differential equations obtained by the numerical continuation method and the parameter-splitting multiple-scales method are compared to address ① the transverse static load effect on the frequency-response and nonlinear dynamical behavior of the beam, ② the discrepancies between the resultant frequency-response curves obtained by using two different mode shapes and ③ the efficacy of the parameter-splitting multiple-scales method on solving strongly nonlinear practical problem.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-09T07:00:00Z
      DOI: 10.1142/S0219455425501287
       
  • A Novel Weak-Form Plane Frame Quadrature Element and its Application to
           Bridge Analysis

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      Authors: Kai Wang, Chuang Feng, Ding Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A novel weak-form plane frame quadrature element (WPFQE) is developed. A complex structure can be divided into several non-homogeneous (or homogeneous) elements with large size. The Chebyshev–Lobatto differential quadrature dealing with differentiation and the Gauss–Lobatto quadrature dealing with integration have the same integration points including the ends of each element. Based on the energy variational principle, the diagonal mass matrix and positive definite real symmetric stiffness matrix for the element can be obtained. The unknown quantities at the internal quadrature points of the element can be represented by those at the endpoints of the element based on the principle of static equal effect anterior to the development of global matrices, which significantly reduces the sizes of modified element matrices while maintaining sufficient accuracy, thereby obtaining the small-sized global matrices. Assembly of elements can be performed efficiently just as that in the finite element (FE) method. In the case study, the static and dynamic performances of a three-span high-pier rigid-frame bridge with variable cross-section are studied by applying the proposed method. The results indicate that the orders of structural matrices and calculation time obtained by the WPFQE method are much smaller than those of the FE method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-09T07:00:00Z
      DOI: 10.1142/S0219455425501536
       
  • Research on Dynamics Characteristics of Grounded Damping Nonlinear
           Energy Sink

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      Authors: Zijian Yang, Jun Wang, Jianchao Zhang, Yongjun Shen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The nonlinear energy sink (NES) system mainly dissipates energy through damping elements, and changing the position of the damping element will also change the performance of the NES. In this paper, a grounded damping NES is proposed by grounding the damping element of the traditional cubic stiffness NES. The complex dynamics of this two-degree-of-freedom system are investigated. The slow-varying equations of the system under 1:1 internal resonance are derived by using the complexification-averaging (C×A) method, based on which the influence of the primary structure’s damping on a bifurcation is analyzed. The conditions for the existence of strongly modulated response (SMR) are studied, and the accuracy of the results is verified using the slow invariant manifold (SIM), Poincare mapping, and time-history diagrams. This provides a means of verifying the analytical findings. The vibration suppression effects of the grounded damping NES, as compared to the cubic stiffness NES, are thoroughly studied under both pulse and harmonic excitations. The results indicate that the main structure damping affects the stability of the system and the occurrence of the SMR. Most previous studies of the NESs have overlooked the effect of main structure damping, which may influence the selection of structural parameters. Moreover, under relatively large pulse or harmonic excitations, the vibration suppression effectiveness of the grounded damping NES surpasses that of traditional cubic stiffness NES. This finding has important practical significance for improving the vibration suppression effect and robustness of the NES, and provides a reference for the structural design of the NES.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-09T07:00:00Z
      DOI: 10.1142/S0219455425501561
       
  • Performance Evaluation and Comparative Analyses of Tuned Inerter Damper
           for Stochastic Base Excited Structures Based on Hybrid [math] Optimization
           

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      Authors: Ruoyu Zhang, Jizhong Huang, Yuan Cheng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Compared with tuned mass damper, tuned inerter damper (TID) has higher damping efficiency and lightweight characteristic if appropriate optimal methods are selected. Generally, [math] or [math] optimal methods are adopted to determine the optimal parameters of TID individually. But the vibration mitigation performance of the TID under near resonance frequency band based on [math] optimization is less than [math] optimization, but the peak frequency response based on [math] optimization will be greater than [math] optimization at the same time. Dual-characteristic-based vibration control may not be achievable based on [math] or [math] criteria, respectively. For this reason, hybrid [math] optimization can be adopted. In this work, closed-form expressions are derived for the control of structural displacement responses based on hybrid [math] optimal method. The vibration mitigation performance of the different optimized TIDs is evaluated considering the single-degree-of-freedom and multi-degrees-of-freedom systems are subjected to typical ground motions excitation. Results illustrate that because of the use of the optimal stiffness ratio of [math] optimization and very close value of [math] optimizations’ nominal damping ratio in [math] optimization, [math] optimization shows ‘dual characteristics’ in different excitation situations. Specifically, the peak response and structural fundamental frequencies’ response in displacement frequency response function using hybrid [math] optimal methods are between [math] and [math] optimization, which indicates an excellent and balanced control performance combining the advantages of [math] and [math] optimal solutions. Hence, this hybrid method is more suitable for more complex ground motions excitation to control critical structural responses instead of single characteristic excitation. And the comprehensive vibration control in dynamic time histories analyses can be achieved by this dual characteristic-based optimal strategy. When designing the specific TID, hybrid [math] optimization can be considered as the best choice for its compatibility and high adaptability for complex practical engineering scenarios with random and diverse excitations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-06T07:00:00Z
      DOI: 10.1142/S021945542550110X
       
  • Stochastic Analysis for the Embedded Single-Walled Carbon Nanotube Under
           Random Vibrations

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      Authors: Zheng Zeng, Kang Lu, Xuefeng Wang, Rongchun Hu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      It is inevitable that carbon nanotubes (CNTs) are subjected to random vibrations due to environmental noise, which may impair their mechanical properties. The nonlinear dynamics associated with single-walled carbon nanotubes (SWCNTs) under random noise has been investigated in this work. First, based on the nonlocal theory and the Euler–Bernoulli beam model with fixed supports at both ends, the governed equations and boundary conditions are established according to Hamilton’s principle. Second, the Galerkin method is used to approximate the differential equations of motion and the stochastic averaging method (SAM) is applied to predict the approximate response of the original system. Subsequently, a detailed parametric study is conducted to analyze the nonlinear random vibration response of the SWCNT with nonlocal effects, and the effectiveness of the proposed method is verified by comparing the analytical results with those from the Runge–Kutta method. Finally, by solving the backward Kolmogorov (BK) equation and the generalized Pontryagin (GP) equation simultaneously, the conditional reliability function (CRF) and mean first-passage time (MFPT) for determining the reliability of SWCNT systems are obtained.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-05T07:00:00Z
      DOI: 10.1142/S021945542550083X
       
  • The Thermodynamic Responses of FG Conical/Cylindrical/Annular Panels with
           Circumferentially Variable Dimensions

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      Authors: Xuanzhi Shi, Rui Zhong, Qingshan Wang, Xianjie Shi, Zhou Huang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper is the first to develop a meshless thermodynamic model with circumferentially variable dimensions to analyze the thermal-vibration mechanisms of typical functionally graded (FG) panel-type structures, mainly including conical, cylindrical, and annular panels. The longitudinal variation of the panel-type structure’s circumferential dimensions is taken into account according to specific rules. The Thin Plate Inverse Mapping (TPIM) meshless shape functions are introduced to characterize the displacement components associated with each substructure. Thermodynamic equations are formulated based on FSDT thermo-elastic theory as well as Hamilton’s principle. Rectangular and exponential pulse loads are taken into consideration for forced vibration analysis in this formulation. Numerical convergence and comparative cases are provided. Solutions from the literature and finite element simulation results are utilized for comparison, revealing that the percentage differences observed are all less than 0.025%. This confirms the reliability and accuracy of the developed analysis model. In conclusion, a detailed investigation is conducted on the influences of geometrical dimensions, boundary conditions, as well as thermal and external loads on the thermodynamic behaviors of FG panel-type structures with circumferentially variable dimensions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-05T07:00:00Z
      DOI: 10.1142/S0219455425500956
       
  • Research on Structural Damage Identification of Shear Buildings Based on
           Modal Curvature Change

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      Authors: Huahua Qiu, Cuikun Wang, Caihua Chen, Mingzhe Cui, Shengyuan Qiu, Pengfei Zhao, Jianguo Nie
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In the past few decades, various techniques for structural damage identification based on dynamic properties have been widely studied, among which modal curvature is the research hotspot, due to its high sensitivity to local damage. To realize story-level structural damage identification of shear buildings, this paper first derives the patterns of variation in modal curvature of the damaged structure. Then, a new damage index sensitive to local damage called the Modal Curvature Change modified with Softmax (MCCSM for short), is proposed to improve the accuracy of structural damage identification. Afterward, the validity of the damage index is verified by a shaking table test of a scaled RC frame structure model and its corresponding numerical model. The research results show that the damage location indicated by MCCSM corresponds well with the damage phenomenon in the shaking table test and numerical simulation; compared with using the theoretical mode shape, the MCCSM index can give comparable damage identification results using the mode shape obtained through operational modal analysis from vibration time-history data, which proves the feasibility in engineering practices; through numerical simulation, it is proved that the MCCSM index is applicable in a wide range of damage cases with different story position, number of damaged story, and damage extent.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-05T07:00:00Z
      DOI: 10.1142/S0219455425501056
       
  • Ritz Solutions of Stationary Random Vibrations for GPL-Reinforced FG
           Rectangular Plate

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      Authors: Xuanzhi Shi, Bin Qin, Xianjie Shi, Rui Zhong, Qingshan Wang, Hailiang Yu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper aims to establish a comprehensive model for evaluating the response characteristics of functionally graded graphene platelet-reinforced composite (FG-GPLRC) rectangular plates under stationary random acceleration excitation. Utilizing the first-order shear deformation theory (FSDT) and Halpin–Tsai assumptions, a dynamic model for the rectangular plate is derived, followed by obtaining the variational solution using the Rayleigh–Ritz method. To describe displacement components associated with dynamic equations and boundary conditions, a spectral geometry method (SGM) is employed. Additionally, a pseudo-excitation method (PEM) is utilized for the analysis of stationary random vibration. The proposed calculation method is validated through convergence analysis and comparative evaluation with existing literature and finite element models. Furthermore, the study investigates the influence of various factors, such as boundary conditions, the number and size of functionally graded rectangular plate layers, GPL distribution types, and material parameters, on the stationary random response attributes of FG rectangular plates. This research contributes to a deeper understanding of the dynamic response of functionally graded materials in structural configurations and offers a valuable analytical approach for researchers in this field.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-05T07:00:00Z
      DOI: 10.1142/S021945542550107X
       
  • Vibration Study of Functionally Graded Microcantilever Beams in Fluids
           Based on Modified Couple Stress Theory by Considering the Physical Neutral
           Plane

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      Authors: Jize Jiang, Feixiang Tang, Sen Gu, Siyu He, Fang Dong, Sheng Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Theoretical studies on the vibration of microcantilever beams in fluids, which are commonly used in micro- and nanoelectromechanical systems (MEMS/NEMS). When microcantilever beams are subjected to photo-thermal excitation, they show that the material properties such as the dynamic response and the one-dimensional temperature field will show significant differences from the macroscopic properties when the size appearance of the microbeam decreases to the scale below a dozen micrometers. In this paper, by correcting the scale constants of the beams, the photothermal vibration model of the microbeam is established using the physical neutral plane theory. The one-dimensional heat transfer equations and scale-corrected temperature field of the microcantilever beam under laser excitation are derived, which are solved by Galerkin’s method, based on the theory of thermoelasticity, the hydrodynamic model of the beams vibrating in incompressible liquids proposed by Sader et al. and the theory of Euler–Bernoulli beams. The equations governing the vibration of micro-cantilever beams corrected for scale effects in different fluids when subjected to photothermal excitation are obtained. The results show that the temperature field, resonant frequency, and quality factor of the microbeam will have a significant upward drift when the size of the microbeam is close to the scale parameter, and the scale effect has a non-negligible influence on the macroscopic performance parameters; the upward drift is gradually weakening when the thickness to scale ratio gradually increases. Finally, the property of the beam is almost the same as that of the theory when the thickness of the beam is 10 times the scale constant. The correction of the theory by the scale effect is insignificant.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-05T07:00:00Z
      DOI: 10.1142/S0219455425501093
       
  • Novel Phononic-Like Crystal Wave Barrier Structure for Vibration Isolation

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      Authors: Peng Xiao, Linchang Miao, Haizhong Zheng, Benben Zhang, Lijian Lei
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      As an efficient, environmentally friendly, and economical urban public transportation tool, the subway has significant advantages compared to other urban public transportation tools and plays an irreplaceable role in the urban rail transit system. While the subway brings many conveniences to people, its operation has also brought a series of problems to urban development and residents’ lives, especially the vibration and noise problems generated by the subway have become unavoidable and urgent problems to be solved. The traditional wave barriers have a certain effect on attenuating and suppressing the vibration generated by the subway, but it has shortcomings in terms of the width and quantity of elastic wave bandgap (BG), so its application in low-frequency vibration reduction and isolation of subway systems is greatly limited. In order to broaden the elastic BG width and quantity of the wave barrier, this paper designs a novel phononic-like crystal subway wave barrier (PLCSWB) for subway vibration isolation based on locally resonant theory. Firstly, the dispersion curves of the novel PLCSWB are calculated using the improved plane wave expansion method and finite element method (FEM), and compared with the dispersion curves of traditional phononic crystal (PC) wave barriers. Secondly, the frequency response function of the novel PLCSWB is calculated using FEM to evaluate its attenuation effect on vibration, and the energy distribution characteristics at its BG boundary are analyzed. Then, the main factors affecting the BG of the novel PLCSWB are analyzed, and a spring–mass system equivalent model of the novel PLCSWB is established to theoretically estimate its BG range. Finally, the vibration data of the tunnel wall monitored on site are used to analyze and verify the vibration isolation effect of the novel PLCSWB. The results show that the novel PLCSWB opens five low-frequency BGs in the 200[math]Hz frequency band, which increased the total width of the opened BGs by 49% compared to traditional PC wave barriers. In the frequency range of the BG, the attenuation value of the novel PLCSWB to vibration is mostly above 30[math]dB, and the energy distribution inside the structure is mainly concentrated in the primitive cell that controls the BG, indicating good attenuation and control effects on vibration. The main factors affecting the BG of the novel PLCSWB are the density of the scatterer material, the elastic modulus, and the thickness of the wrapping layer material. Moreover, during subway operation, the novel PLCSWB has a good attenuation effect on the vibration transmitted from the tunnel wall to the soil. Among them, the maximum vibration acceleration amplitude of the novel PLCSWB with nine rows is reduced by 47%, and the vibration isolation performance is remarkable. The relevant research results of this paper provide a novel approach and method for the study of subway vibration reduction and isolation, and can also provide specific references for the design and development of wave barriers.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-03T07:00:00Z
      DOI: 10.1142/S0219455425501160
       
  • Fast Calculation for Vehicle–Road Coupled Response Based on Cyclic
           Road Modeling Method

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      Authors: Chao Li, Jilin Hou, Qingxia Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In order to improve the computational efficiency of the vehicle–road coupled response in long-distance driving, this paper proposes a cyclic road modeling method to equivalent an infinitely long road. The road is built using a closed model, and the vehicle–road coupled response is calculated assuming that the vehicle numerically cyclic driving. First of all, the concept of the cyclic road model is introduced, and the modal analysis is performed. Secondly, the principle for determining the optimal length of the cyclic road model is proposed based on the attenuation properties of the road response in time and space. Next, the vibration analysis of the vehicle–road coupled system is conducted, and its equation of motion is constructed using the mode superposition method (MSM). Further, the optimal length of the cyclic road model is derived regarding to road parameters via numerical analysis. At last, the application of this cyclic road model on computing the vehicle–road coupled response in long-distance driving is discussed via numerical simulation. The results indicate that this model has a consistent performance with the widely used models, while significantly improves computational efficiency. The proposed method also provides a new idea for the fast modeling of roads.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-03T07:00:00Z
      DOI: 10.1142/S0219455425501457
       
  • Random Vibration Analysis of Double Deck Rocking Self-Centering Pier Under
           Seismic Excitation

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      Authors: Yebao Feng, Lincong Chen, Jiajie Kang, Huiying Hu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates nonlinear random vibration of double deck rocking self-centering pier structure subjected to seismic excitation. First of all, a novel type of double deck rocking self-centering pier that offers better resilience is designed. The stochastic dynamical model of the system is then established, in which the seismic excitation is viewed as Kanai–Tajimi filtered white noise and the self-centering restoring force is characterized by classical flag-shaped hysteretic model. Subsequently, the self-centering restoring force is decomposed into equivalent quasi-linear elastic and damping forces by adopting the harmonic balance (HB) scheme. Following this, the stochastic averaging (SA) technique is implemented to derive the averaged Itô equation. The steady-state response probability density with respect to the amplitudes is solved from the averaged Fokker–Planck–Kolmogorov (FPK) equation. Finally, the effects of system parameters on the stochastic response of the double deck rocking self-centering pier structure are performed, and validated by the Monte Carlo simulation (MCS). In addition, with the help of the Laplace transform, the transition function as well as conditional power spectral density are achieved, which are combined with the steady-state probability density to obtain the power spectral density response. This research will contribute to the optimal seismic design of double-deck rocking self-centering piers.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-03T07:00:00Z
      DOI: 10.1142/S0219455425501500
       
  • Stability of Prestressed Stayed Steel Columns Under Eccentric Compression

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      Authors: Zhiyu Zhang, Pengcheng Li, Chenglin Liu, Xiujun Wang, Tianhao Zhang, Gang Xiong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Prestressed stayed steel columns (PSSCs) are structural components notable for their exceptional stability and load capacity. However, their behavior under eccentric compression remains poorly understood compared to their performance under axial compression. This study conducted tests and finite element analysis (FEA) to investigate the stability of PSSCs under eccentric compression loading. The study focused on examining the overall stability, buckling modes, and ultimate load capacity of PSSCs under various scenarios. The findings revealed that PSSCs exhibit significantly higher stability and load capacity than conventional columns. However, when subjected to eccentric compression, they experience a substantial decrease in stability. The results of the linear and nonlinear buckling analyses suggest that interactive buckling may occur under certain conditions, thereby influencing the buckling load. These findings clarify the correlation between stability and eccentric compression, offering valuable insights for future research and practical engineering applications.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-02T07:00:00Z
      DOI: 10.1142/S0219455425501445
       
  • General Theory for Damped Beams with Elastic Supports Subjected to a
           Moving Damped Sprung Mass

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      Authors: K. Shi, X. Q. Mo, S. Y. Gao, H. Yao, Y. B. Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Previously, classical boundary conditions (i.e. simple, fixed and cantilevered) have been adopted for the beams under the moving loads in deriving the dynamic response. In reality, most beams cannot be simply classified as the ones with classical supports, but are elastically restrained. For theoretical completeness, a general theory will be developed in this note for the damped beams with elastic restraints modeled by vertical and rotational springs subjected to a moving damped sprung mass. Essential to the present theory is the solution of the transcendental equation for the frequency by the bi-section method. The solution obtained can also be applied to the classical boundary conditions (i.e. simple, fixed and cantilevered) under a moving sprung mass. The reliability of the present theory, along with the bi-section method for solving the frequency and mode shape, is validated by comparison with the solution obtained by the finite element method (FEM) for various damping ratios, mass ratios and running speeds of the sprung mass.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-07-02T07:00:00Z
      DOI: 10.1142/S0219455425501524
       
  • Dynamic Response Analysis of Moving Trains Passing Through the Stationary
           Thunderstorm Downburst Wind

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      Authors: Fei Zhang, Peng Hu, Yan Han, C. S. Cai, Dan He, Fei Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The safety of the high-speed train traveling through the stationary thunderstorm downburst wind was studied. First, a thunderstorm wind test device was used to simulate the stationary thunderstorm downburst wind. Based on the rigid model pressure measurement tests, the aerodynamic forces of the train traveling along different paths through the stationary thunderstorm downburst wind were measured. The influence of the radial distance of the crossing path on the aerodynamic force coefficients of the train was investigated. On this basis, an unsteady aerodynamic model of the high-speed train crossing through the stationary thunderstorm downburst wind was established, and dynamic response analysis was carried out using the SIMPACK multibody dynamics simulation software to explore further the safety of the high-speed train crossing through the stationary thunderstorm downburst wind. The research showed that the stationary thunderstorm downburst wind field has significant spatial variation characteristics compared with the atmospheric boundary layer wind field. When the train passes through the thunderstorm downburst wind, the radial wind speed and wind yaw angle experienced by the train constantly change, and the change curve shows a symmetrical distribution. The aerodynamic force of the train will undergo sudden loading and unloading processes, and the lateral force coefficient of the train on different paths shows a “pulse-type” variation. Moreover, the lateral force coefficient increases with the increase of wind yaw angle. Under the influence of the thunderstorm downburst wind, the variation trend of the aerodynamic force coefficients of the train is consistent with that under crosswind. However, there are significant differences in the numerical values. Therefore, it is impossible to simply use the formula for calculating the aerodynamic force coefficients of the train under crosswinds to predict the aerodynamic force coefficients of the train under the thunderstorm downburst wind. While passing through the thunderstorm downburst wind, the overturning coefficient index plays a decisive role in the safety of train operations. Train rollover is the main form of train safety accidents, while derailment accidents are not easy. The numerical results obtained in this study are significant for evaluating the operational safety while moving trains traversing the stationary thunderstorm downburst wind.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-29T07:00:00Z
      DOI: 10.1142/S0219455425501482
       
  • Aerodynamic Performance of Leeward Side One During Trains Meeting on
           High-Speed Railway Bridges in Crosswinds

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      Authors: Wei Tao, Ping Lou, Zhen Sun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      When high-speed trains (HSTs) meet on a bridge in a crosswind environment, the train on the windward side (TWS) will produce a wind-shielding effect similar to a windbreak. This effect, coupled with the instantaneous pressure wave generated at the time of the meeting, will cause an abrupt variation in the aerodynamic load of the train on the leeward side (TLS) during the meeting process, thereby affecting the safe and stable operation of the train. This study analyzed the factors affecting the degree of the abrupt variation in the aerodynamic load of the TLS during the meeting, and studied the change rule of the safety index of the TLS under different wind speeds. In addition, we also explored the impact of three types of ventilation rate curved wind barriers on the abrupt variation in the aerodynamic load of the TLS during the meeting. The research results show that the increase in crosswind speed will increase the degree of the abrupt variation in the aerodynamic load of the TLS, further exacerbating the impact on the safe and stable operation of the TLS. Although the increase in train speed will reduce the magnitude of the abrupt variation in the aerodynamic load of the TLS during the meeting, it will increase the rate of abrupt variation. However, a curved wind barrier with a ventilation rate of 30% can effectively alleviate the abrupt variation in the aerodynamic load of the TLS during the meeting. These research results have important reference value for improving the driving safety of HSTs in crosswind environments.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425400036
       
  • Investigation of Dynamic Coupling Effect on Bridge Frequency Measurement

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      Authors: Judy P. Yang, Han-Cyuan Jiang, J. D. Yau, Shota Urushadze
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a multidisciplinary approach combining a numerical analysis in three dimensions and a laboratory test is developed to investigate the dynamic coupling effect as induced by vehicle–bridge interaction in the indirect measurement. To unveil such dynamic coupling and its influence on the frequency measurement, a single degree-of-freedom test vehicle is exclusively designed with adjustable frequency, which is a low-cost, easy-to-use, and reliable tool for measuring beam frequencies in the laboratory while providing valuable data for validating numerical models, calibrating sensors, and evaluating bridge performance. From the multidisciplinary analysis, the shifts of frequencies for both vehicle and bridge are consistently demonstrated as a result of vehicle–bridge interaction effect. Moreover, for the identification of higher-order bridge frequencies, the contact-point response works better than the vehicle’s response, even with shifted frequencies being observed in the three-dimensional numerical results. As an extension, a parametric study is conducted numerically to include various practical conditions, including different types and boundary conditions of a bridge as well as pavement irregularity.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425400048
       
  • Three-Dimensional Effect of Turbulence on the Gust-Loading and Buffeting
           Response of a Cable-Stayed Bridge with Projecting-Slab Box Girder

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      Authors: Shaopeng Li, Hongsheng Jiang, Yi Su, Kang Shi, Yunfeng Zou, Yi Hui, Jinsheng Wen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Traditional pressure measurements fail to determine the buffeting force on bridge decks with complex configurations, such as truss or box girders with two slabs. The high-frequency force balance (HFFB) provides an efficient way to solve this aerodynamic issue. This work aims to clarify the spatial distribution characteristics of gust loading acting on a strip of a bridge deck with a projecting slab using force measurements with double-HFFBs. Based on Ribner’s three-dimensional (3D) spectral tensor theory, the relationship between the buffeting forces on an equivalent strip and segment can be derived. The three-dimensional aerodynamic admittance (3D) can be identified considering the 3D effect of turbulence, which can be decoupled into 2D AAF and spanwise correction factor. The results show that the influences of segment lengths and turbulence on the 2D AAF and coherence of the equivalent strip can be eliminated, indicating the validity of the proposed approach. Finally, the applicability of strip theory in estimating the buffeting response of long-span cable-stayed bridges is investigated using finite element analysis.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425500828
       
  • Research on the Damping Characteristics of Partially Filled All-Composite
           Honeycomb-Core Sandwich Panel

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      Authors: Zhuo Xu, Nan Yao, Hui Li, Chen Chu, Yong-Feng Zhang, Da-Wei Gu, He Li, Qing-Kai Han, Bang-Chun Wen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a novel theoretical approach based on high-order shear deformation theory is proposed to investigate the damping properties of honeycomb panels partially filled with foam. The assessment of damping properties in composite materials is accomplished through finite element theory, which elucidates the theoretical underpinnings for determining damping parameters specific to these materials. Subsequently, the damping parameters of the partially foam-filled honeycomb panel are determined based on the ratio of dissipated energy to strain energy. Ultimately, a comprehensive theoretical testing methodology is established, with tests conducted concurrently on composite materials to benchmark against data obtained via theoretical approaches. The findings underscore the capability of the proposed approach to assess the damping characteristics of diverse materials and extract their corresponding damping parameters. This method provides an effective theoretical model for investigating the damping characteristics in partially foam-filled fully composite honeycomb core sandwich structures. The model can also be applied to assess the damping properties of similar structures, offering practical guidance.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425501081
       
  • Thermoelastic Damping of Micromechanical Resonators Based on Quintanilla
           Theory

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      Authors: Pravin Kumar, Roushan Kumar, Rajesh Prasad
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper addresses the exploration of thermoelastic damping (TED) in a microbeam resonator, utilizing the Quintanilla generalized thermoelasticity theory. The study emphasized analyzing the influence of beam height on the microbeam resonators TED and also conducted a thorough assessment of the frequency shift and normalized attenuation in microbeam resonators. These outcomes are then compared with different materials, like silicon (Si) and lead (Pb). The current undertaking demonstrates its utility in tackling challenges associated with science and engineering.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425501299
       
  • Reliability Estimation of Weibull Distribution with Zero-Failure Data

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      Authors: Jin Guo, Xiangwei Kong, Ningxiang Wu, Liyang Xie
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper focuses on the reliability estimation of Weibull distributions with zero-failure data. Since no product failure occurred in the tests, the conventional maximum likelihood method was not applicable. Recent methods ignore the estimation of location parameter and tend to be conservative. This study developed a new estimation technique to address these problems. A prior model between the life dispersion boundary and shape parameter is constructed by considering the historical failure data of similar high-reliability products. The failure probabilities for all samples were inferred using the E-Bayesian method, after which the reliability was estimated. Afterward, a confidence interval for reliability was obtained based on the bootstrap confidence interval and modified maximum likelihood method. A Monte Carlo simulation study demonstrated that the proposed method is satisfactory in terms of point estimates, confidence intervals, coverage probabilities, and computational efficiency. Finally, a real engineering example is introduced to illustrate the application of this method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-28T07:00:00Z
      DOI: 10.1142/S0219455425501512
       
  • Automated Experimental Modal Analysis for Bridges Using a Cogwheel

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      Authors: Jan Bayer, Shota Urushadze
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      An automated input–output experimental modal analysis technique has been developed and tested on a scaled laboratory model. An impulse force is generated by a heavy cogwheel (CW) at equidistant steps along a chosen driving path on a bridge. At least two accelerometers are required in order to evaluate the modal properties. Since the quality of the impact signal is not ideal, the moving mass along with corresponding frequency changes are applied to evaluate the mass-proportional mode shapes of the bridge with the CW mass eliminated. As an alternative, the mode shapes can be obtained from the relations between the fixed and moving accelerometers. The main advantage and novelty is that the process can be automated. Also new is the fact that a CW is applicable to experimental modal analysis as an exciter. The method provides modal parameters based on a dense network of measuring points.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S021945542540005X
       
  • Vibration Analysis of Power Law Functionally Graded
           Magneto-Electro-Elastic Plate

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      Authors: Hamdi Ezzin
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Functionally-graded materials (FGMs) have great potential in many industry areas for the development of novel acoustic devices such as sensors, electromechanical transducers, actuators and filters. The study of the propagation of elastic waves is a primordial step for a number of such applications. In this study, the stiffness matrix method and the Stroh formalism with the formulation of Ingebrigsten and Tonning were used to establish the relationship between the stress and displacement from the top to the bottom of the fictive multilayer. A power-law inhomogeneity distribution is introduced in the mechanical tensor of the magneto-electro-elastic (MEE) composite. The obtained results indicate that the introduction of heterogeneity has a great influence on nondimensional frequency and modal shape. It is also found that the frequency vibration decreases with the increase in gradient coefficient [math]. Furthermore, the metallization of the free surface (vanishing of electrical and magnetic potential) highly decreases the stress, especially in the median of the plate.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425500774
       
  • Crashworthiness Study of Hexagonal Honeycomb Based on Fractal Design

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      Authors: Chengming Wang, Xiaolin Deng, Fumo Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a novel approach to enhance the energy absorption (EA) of honeycombs in the out-of-plane direction. Inspired by the Koch fractal, a fractal hexagonal honeycomb (FHH) is presented in this paper. In our study, we use Abaqus/Explicit to build a finite element model of the honeycomb, through which we conduct a series of studies on the performance of this honeycomb. Initially, we compare the mechanical properties and deformation modes of the FHH with those of a conventional hexagonal honeycomb. The results demonstrate notable improvements in crashworthiness metrics for the FHH, including a 52% increase in specific EA, a 45% enhancement in crushing load efficiency (CLE), and an 8% reduction in peak crushing force (PCF) compared to the conventional counterpart. Subsequently, this paper investigates the fractal arc honeycomb and evaluates the effect of the center angle on mechanical properties by varying its value. Furthermore, the mechanical properties of layered honeycomb and fractal honeycomb structures with different wall thicknesses are systematically examined. In the last section, we explore the theoretical analysis of the fractal-hexagonal honeycomb and find that the results of the theoretical analysis are in good agreement with those of the simulation, indicating that the experimental simulation results are reliable. Overall, the findings of this study offer valuable insights for the innovative design of hexagonal honeycomb structures, providing a reference for future advancements in this field.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425501159
       
  • Vibration Analysis of Rotating Annular Flexoelectric Microplate

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      Authors: S. M. H. Hosseini, Y. Tadi Beni, Y. Kiani
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This research investigates the free vibration of a rotating annular microplate under the flexoelectric effect. Initially, the Kirchhoff plate theory assumptions are used to express the displacement fields. After considering the displacement field, strains and their gradients are derived and substituted into the electric enthalpy and kinetic energy expressions. Subsequently, by applying Hamilton’s principle to the aforementioned equations, the electric and mechanical equations are computed. To derive the equations of motion, initially, the polarization vectors and their gradients are derived from the electric equations and associated boundary conditions. Subsequently, these are incorporated into the mechanical equations, which also encompass electric components. It is notable that by removing the time-dependent terms from the in-plane equations of motion, the static displacement due to rotation at each speed is obtained. After deriving the equations of motion and boundary conditions, these equations are non-dimensionalized using non-dimensionalizing relations. In the next step, Hamilton’s principle is used to discretize the equations and boundary conditions. Consequently, by applying the generalized differential quadrature method and extracting the stiffness and mass matrices resulting from the transverse equation of motion and boundary conditions, the natural transverse frequency of the rotating annular microplate under the flexoelectric effect is calculated. The results of this research are useful for promoting the use of rotating annular microplants under flexoelectric effect for microelectromechanical systems designers with high efficiency.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425501263
       
  • Damage Identification of Offshore Platform Structure Based on Earch Model
           and Optimized KPCA Under Environmental Interference

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      Authors: Jiancheng Leng, Jinbo Zhang, Jianghong Yue, Huiyu Feng, Yang Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The influence of damage on structural characteristic parameters is often obscured by the complex and changeable marine environment, which may lead to damage misjudgment. Aiming at this problem, a time domain structural damage identification method based on exponential autoregressive conditional heteroskedasticity (EARCH) and kernel principal component analysis (KPCA) is proposed. First, the vibration modal component of the structure is obtained by the reduced-order variational mode decomposition method. Then, the EARCH model is established and the damaged feature matrix of the structure is extracted. After that, KPCA after parameter optimization is used to eliminate the influence of environmental changes on damage identification results. Finally, the SPE damage index is constructed to complete the damage identification of the structure. The structural damage identification was carried out on 16 test conditions under different environmental disturbances, based on indoor offshore platform vibration tests. The results show that the accuracy recognized by the proposed method reaches 98%, which is 4% higher than the traditional KPCA method based on EARCH model features, demonstrating the effectiveness of this approach. Furthermore, the method was applied to real offshore platform data, and the results show that the structural damage state is accurately identified even in the presence of typhoon interference, which is 16% higher than the traditional KPCA method, proving its feasibility and robustness.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425501354
       
  • Online Learning Deep Neural Network Fuzzy Control of Structures Under
           Earthquake Motions: Numerical and Experimental Tests

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      Authors: Yang Lv, Jiantong Hui, Bo Zhong, Fanxing Zhang, Zehua Ren, Fangfang Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The conventional control methods typically assume that the controlled structure behaves as a deterministic system, overlooking variations in structural dynamic properties and uncertainties in earthquake motions. To overcome this constraint, this study introduces an innovative approach: an online learning deep neural network fuzzy control method (DFNN). In the proposed method, Offline training was conducted using training samples generated through the Linear–quadratic regulator (LQR) to determine the initial parameters of DFNN. An ON–OFF system was introduced for real-time control signal adjustment. The input and corrected control signals were utilized as training samples to train and modify the parameters of the DFNN system, enabling online learning capabilities. Numerical and experimental investigations were performed to evaluate the effectiveness of passive control (OFF), fuzzy logic control, deep neural network fuzzy control, and online learning deep neural network fuzzy control using a numerical three-story steel frame structure and an experimental two-story steel frame structure with one magneto-rheological (MR) damper. The simulation and shaking table test results demonstrate that DFNN can adaptively adjust the parameters of the neural network, leading to significantly higher control efficiency compared to fuzzy logic control and deep neural network fuzzy control, particularly when the structural properties and earthquake motions differ from the training samples.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425501433
       
  • On the Spatial Buckling of Elastic Columns

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      Authors: Peter Kočman, Simon Schnabl, Igor Planinc
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a novel analytical solution for the buckling load in 3D of columns that fills a gap in the existing literature by accounting for shear deformation and spatial effects. The latter means that a column can be supported and buckle in any direction. We build on the foundational work of Simo and use a 3D beam model to derive a set of equations that form the basis for our analytical solution. The paper outlines the axioms of the Simo model, presents the corresponding equations, and describes the linearization procedure in details. By linearizing the equations we obtain a set of algebraic equations with boundary conditions, which we manipulate into an analytical solution for the buckling load. An illustrative example using a column with an elliptical cross-section shows how different boundary conditions and the spatial orientation of the column influence the buckling load. This research work not only contributes to the verification of numerical programs, but also provides engineers with a valuable tool for optimizing structural configurations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425501469
       
  • Straight-Beam Approach for Vibration Analysis of Horizontal Curved Beams

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      Authors: Y. B. Yang, Y. H. Liu, H. Xu, Y. Z. Liu, D. Z. Guo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the use of straight-beam elements to simulate the vibration of curved beams that is mathematically more challenging. First, analytical solutions of the out-of-plane and in-plane dynamic responses of the curved beam are derived for reference. Then, for the straight beam approach, the elastic stiffness matrix, consistent mass matrix, consistent nodal loads, and transformation matrix are derived and included in a procedure for computing the dynamic responses of the curved beam. The effectiveness of the straight beam approach in analyzing the free vibration and forced vibration (induced by moving vehicle) of the curved beam is validated, with the results compared with the theoretical solutions and those by Abaqus. It can be concluded that the straight beam approach is a simple and efficient means for analyzing the out-of-plane and in-plane vibrations of curved beams with high precision.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-27T07:00:00Z
      DOI: 10.1142/S0219455425710026
       
  • Chaotic Criterion for Micro-Cantilevers of Atomic Force Microscopes

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      Authors: Zhichao Wu, Qiliang Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The cantilevered micro-beam is an important component in the field of Atomic Force Microscope (AFM) and its behavior is governed by chaotic dynamics. To better understand these dynamics, a theoretical model based on the Euler–Bernoulli beam model has been developed and experiments have been conducted. The model incorporates both the modified couple stress theory (MCST) and external forces to account for the size-dependent effect and electrostatic load. The reduced model in one degree of freedom is obtained by the Galerkin method. The validity of the reduced model is tested by comparing the results from simulations and published results and experiments. The Melnikov method is then used to detect the chaotic threshold the cantilevered micro-beam. The numerical results test the effects of MCST on the complex responses of the micro-cantilever. Implications of the research can extend to the design and optimization of MEMS devices.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501111
       
  • Variational Principles of Nano Laminated Composite Plates with
           Flexoelectric Effect

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      Authors: Tao Fan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Flexoelectric effect is strengthened in dielectrics at nanoscale so that it could not be neglected. In this work, a laminated composite plate with flexoelectric core and two coverings of CNTRCs is modeled. The variational principles of the plate with generalized supporting conditions are derived considering both the flexoelectricity of the piezoelectric core and the reinforcement of the CNTRCs. According to it, the governing equation and boundary conditions with any supporting types are obtained. Then the analytical solutions to the displacements and resonant frequencies of the plate with two different boundary conditions for free vibration are given. The numerical results prove that the flexoelectric effect relies on the scale seriously. Moreover, the CNTRCs coverings can improve the bending stiffness of the whole plate. Therefore, the bending responses such as resonant frequency and bending deflection can be adjusted and optimized by changing the ratio of the CNTs to the matrix. It’s hopeful to provide the theoretical basis of numerical calculation of electronic devices with laminated structures at nanoscale.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501251
       
  • Energy Harvesting Estimation from Vibration of Chopped Fiber
           Rod-Reinforced Microbeams with Piezoelectric Patch Based on Five
           Parameter-Surface-Strain Gradient Beam Model

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      Authors: Mohammed Balubaid, Ahmed Ramady, S. R. Mahmoud, R. Kolahchi, B. Keshtegar, S. I. Ali, Ali Algarni, M. Yaylacı, A. Farrokhian
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      During the last years, the design and production of self-powered engineering structures gained extensive attention due to the shortage of nonrenewable energy resources and the increase in fossil fuel prices. To this end, the current numerical study focused on assessing the forced vibration behavior and energy harvesting capability of a silicon microbeam reinforced with chopped fiber rods (CFRs). This topic is important because it offers a novel approach to generate sustainable energy from ambient vibrations, addressing the growing demand for renewable energy sources while advancing structural health monitoring and smart materials technology. The piezoelectric patch is located at the top surface of the microbeam and is under the distributed harmonic force. The related governed relations are derived using the new theory of the five-parameter beam model, which also accounted for the Poisson effect, and solved by adopting the Galerkin method. The microscale effects are taken into account by employing strain gradient theory. Moreover, the effects of the top and bottom surfaces have accounted for the microbeam using Gurtin and Murdoch’s theory. The outcomes of this research indicated that utilizing narrow-short length piezoelectric patches for Silicon microbeams yields the highest available output voltage. Compared to the homogeneous porosity distribution case, as the porosity coefficient reduced in the bottom and top surfaces of the microbeam, the voltage initial rise point decreased by about 13%. By increasing the porosity coefficient to 0.9, both voltage and displacement initial rise points are increased respectively by approximately 32% and 890%. As the piezoelectric patch thickness is decreased from 8[math][math]m to 6[math][math]m while the strain gradient theory is utilized, voltage and displacement initial rise points are increased respectively about 1066.67% and 1[math]200%. Also, a simultaneous increase in CFRs vol. fraction from 5% to 10% and Silicon microbeam thickness from 7[math][math]m to 8[math][math]m caused about 37% improvement in dynamic deflections.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501275
       
  • Hygro-Thermo-Magneto-Elastic Vibration of Multidirectional Graded Porous
           Nanobeams with Axial Motion by Considering Rotary Inertia and Thickness
           Effects

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      Authors: Xiaolan Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Scale-dependent vibration and stability of three-dimensional functionally graded (FG) porous Rayleigh nanobeams with axial motion in varying environmental conditions are investigated by considering scale effects in the thickness orientation. It is supposed that the effective material characteristics of the nanobeam in the longitudinal, width, and thickness orientations are graded according to exponential and power-law functions. Different patterns involving uniform, non-uniform, and logarithmic distributions are considered to model the porosity impacts. Based on the nonlocal strain gradient Rayleigh beam model and incorporating thickness effects, the dynamical equation of the system is derived by considering linear, parabolic, and sinusoidal elastic foundations. The Galerkin discretization technique and Laplace transform are adopted to solve the eigenvalue problem and accomplish the stability analysis. Several comparative studies are performed with the available data in the open literature to validate the solution approach and results. Also, detailed parametric investigations are accomplished to interpret the importance of scale factor, rotary inertia factor, porosity characteristics, magneto-hygro-thermal loads, foundation parameters, gradient indices, and boundary conditions on the dynamical behavior, critical divergence, and flutter axial speeds. The results revealed that, contrary to the effect of the material gradient in thickness orientation, the longitudinal and width gradation of materials can lead to the increment of vibrational frequencies. The outcomes declared that the instability threshold improves significantly by considering the scale effects along the thickness orientation. Also, it is demonstrated that when the middle surface of the cross-section has the highest porosity, the stability regions expand by increasing the porosity coefficient. The present research outcomes can offer valuable insights into the optimum design of high-speed moving multi-directional graded porous nanosystems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501305
       
  • Nonlinear Dynamics of Fluid-Filled Nanocomposite Cylindrical Shells
           Surrounded by Non-Uniform Kerr Elastic Substrates

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      Authors: Vu Ngoc Viet Hoang, Pham Trung Thanh
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a novel analytical framework for investigating the nonlinear dynamic response of functionally graded graphene platelets reinforced composite (FG-GPLRC) cylindrical shells filled with fluids and supported by non-uniform Kerr elastic substrates. The significance of this research lies in its comprehensive exploration of various substrate configurations achieved through discretizing the elastic substrates along the shell’s length. The fluid within the shell is characterized as non-viscous and incompressible, while material properties are rigorously determined using the rule of mixtures and the Halpin–Tsai micromechanical model. At the core of our method lies the establishment of nonlinear kinematic relationships rooted in Donnell shell theory and von Kármán’s nonlinear geometric postulates. We rigorously solve the equations of motion using Galerkin’s technique and the fourth-order Runge–Kutta method. Notably, our enhanced model efficiently accounts for the effect of discontinuities in the elastic foundation’s stiffness solely through integration operations, eliminating the need for intricate algorithms. This approach optimizes computational time and costs. The study conducts a comparative analysis of its results with existing literature, contributing to a thorough understanding of the validity of the proposed approach. We investigate various factors — including material properties, fluid characteristics, and geometric parameters — and their influence on the nonlinear response of nanocomposite shells. Our comprehensive analysis highlights the significant impact of substrate distribution, emphasizing its importance in structural design. Expanding the elastic base area and gradually shifting the elastic foundation toward the central region of the shell positively will affect various factors such as elevating natural frequency and reducing vibrational amplitudes.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501330
       
  • On the Role of Nonlocal Strain Gradient Elasticity in Nonlinear Buckling
           of FG Porous Reinforced Curved Nanobeams Having Different Degrees of
           Curvature

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      Authors: Saeid Sahmani, Babak Safaei, Timon Rabczuk
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Curved nanobeams are one of the essential components in manufacturing nano-electromechanical systems needing nonlinear stability design. In the current investigation, the nonlinear buckling characteristics of functionally graded porous reinforced curved (FGPRC) nanobeams having different degrees of curvature are analyzed by counting the higher-order gradients of the classical strain tensor as well as nonlocal-type interatomic interactions. In this regard, two independent length-scale constants within the framework of the nonlocal strain gradient theory (NSGT) of continuum elasticity are taken into account. Via employing the promising low computational cost and geometrically adaptable method of isogeometric collocation, various branches of NSGT-based equilibrium graphs of FGPRC nanobeams are plotted relevant to each considered degree of curvature. It is extrapolated that the quantity of graphene platelet (GPL) weight fraction has a negligible influence on the significance of nonlocal-type of interatomic size dependency as well as the strain gradient kind of small-scale effect in the value of the maximum deflections or lateral loads at the detected limit points, especially attributed to a higher degree of curvature. Besides, it can be remarked that, in the FGPRC nanobeam owning a small degree of curvature, lessening the quantity of porosity index results in an increment in the significance of the nonlocal-type of interatomic size dependency as well as the strain gradient kind of small-scale effect on the maximum deflection at both upper and lower limit points. However, in the FGPRC nanobeams owning medium and large degrees of curvature, it gets lesser at the upper limit point, but becomes higher at the lower limit one.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501342
       
  • A Convolutional Neural Networks Model Based on Wavelet Packet Transform
           for Enhanced Earthquake Early Warning

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      Authors: Huiwei Wang, Longhe Xu, Xingsi Xie
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The earthquake early warning (EEW) system is critical in mitigating the effects of seismic hazards by providing valuable response time. Damage to buildings can be determined based on peak ground acceleration (PGA). If PGA can be predicted in advance, the seismic risk of a building can be estimated. A novel method for predicting PGA using wavelet packet transform (WPT) and convolutional neural networks (CNN) is proposed. Early arrival waves generated by earthquakes are decomposed using WPT to produce a matrix of wavelet coefficients. This matrix serves as the input to the CNN model to predict the PGA. To achieve the best prediction performance, different setups were investigated, including the use of Daubechies Wavelet 4 (db4) and four-level decomposition. The results indicate that this configuration yields better prediction accuracy. P-waves of three-second duration are commonly used for EEW. Compared to the prediction results of a CNN model used to validate the method, the proposed method has a lower average error and better use of early arrival waves with shorter duration. Overall, the proposed method demonstrates the potential of WPT and CNN in EEW systems. The proposed approach can utilize shorter early arrival waves to predict PGA and gain more reaction time to get rid of seismic hazards. To estimate structural damage using the predicted PGA under an impending earthquake, a method is proposed to quickly determine structural damage based on the predicted PGA and fragility curves. It provides a method to estimate the potential structural damage caused by an impending earthquake.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501366
       
  • Optimizing Viscous Damper Placement for Stochastic Performance of
           Buildings with Plan Asymmetry

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      Authors: Peng-Tai Chan, Quincy Tsun Ming Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Optimized viscous dampers mitigate the dynamic response of building with plan asymmetry. Previous research efforts limit the optimization method to time domain requiring time history analyses to optimize damper placement for plan eccentricity-induced torsional response combined with translational response. This can consume high computational effort and lead to the variability in the ground motion selection. To expedite the optimization process while taking ground motion variability into account, this study will offer a novel criterion based on stochastic performance. This technique will skip the traditional approach of employing time history analyses and will take frequency domain variability into account. Through given distance between the center of mass (CM) and the target frame, the study establishes the stochastic criterion for the response at the perimeter of the building where the maximum torsional-translational response occurs. This allows the optimization methods to generate high quality solution with less computational efforts compared to traditional approach (i.e. time domain-based optimization). It is noteworthy that the proposed criterion is applicable to extensive kinds of responses (e.g. peak floor acceleration, story shear and etc.) once the geometric relationship is given. The proposed criterion as the objective function is compared against their counterpart in time domain through a case study. The case study is based on a reinforced concrete (RC) moment-resisting-frame (MRF) building with two-way asymmetric plan and adopts Element Exchange Method (EEM) to optimize the damper placement. The effectiveness of optimized design based in frequency domain and time domain is evaluated for their total running time and maximum peak interstory drift against a suite of ground motions. The result showed that the proposed criterion can offer the improvement against the traditional approach in terms of solution quality (i.e. performance in time domain and frequency domain) and computational efforts (i.e. total running time for optimization).
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501378
       
  • Vibration Analysis of Perovskite Solar Cells Resting on Porous
           Nanocomposite Substrate in Thermal Environment

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      Authors: Pooya Jafari, Yaser Kiani
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The free vibration analysis of a perovskite solar cell (PSC) within thermal environments is studied through a quasi-3D plate model. This model is designed to account for the stretching effects and non-uniform shear strains throughout the thickness. The PSC film is represented in the model as a thin laminated plate, comprising five distinct plies: ITO, PEDOT:PSS, perovskite, PCBM, and Au. A graphene platelets reinforced composite (GPLRC) substrate, made of Poly (methyl methacrylate), is assumed to be located under the noted five layers. The GPLRC substrate is conceptualized in the model as a porous foundation with finite depth. The foundation stiffnesses are determined using a modified Vlasov model, and the equivalent Young modulus of the foundation is evaluated using a modified Halpin–Tsai model, introducing the porosity coefficient. It is also considered that the material properties of GPLRC substrates exhibit temperature dependency. For the PSC with all edges simply supported, Navier solution method is applied to obtain the frequencies and associated mode numbers. Based on the results presented in this study, an increase in the porosity and thickness of the substrate can negatively impact the frequencies of the structure. However, natural frequencies experience almost no change if the temperature rises.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501391
       
  • Characteristics and Mechanism of Sound Radiation of Urban Railway Bridge
           Installed with Sound Barrier

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      Authors: Xiaoan Zhang, Jianjin Yang, Shengyang Zhu, Wanming Zhai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In noise-sensitive areas of urban rail transit (URT), sound barriers are often used to block the propagation of on-track noise such as the wheel–rail noise. However, the vibrations induced by passing trains can also transmit to the sound barriers. Therefore, it is necessary to study the acoustic radiation characteristics of the sound barrier under moving train loads and to evaluate whether installing sound barriers will affect the overall low-frequency noise radiation from the elevated railway. In this paper, the train–track–bridge dynamic interaction theory is adopted to establish a dynamics model for train–track–bridge-sound barrier coupled system, and the acoustic theory is employed to establish acoustic boundary element models for sound barrier, box girder bridge and sound barrier-box girder bridge coupled system, respectively. These models are then used to systematically analyze the characteristics and mechanism of vibrational noise of the sound barrier due to passing trains. The effects of sound barrier on the acoustic environment are also evaluated. Finally, the influencing mechanism of sound barrier on low-frequency acoustic radiation of elevated railway is investigated, and suggestions for future research on low-frequency acoustic radiation of elevated railway are presented. The research results show that the sound barrier can become a significant low-frequency sound source during the trains passing. Installing sound barriers on elevated railway affects the sound environment around the railway mainly through acoustic effects on the noise propagation. The installation of sound barriers has an effect on the vibration characteristics of the box girder bridge. In order to explore the characteristics of low-frequency sound radiation of elevated railways installed with sound barriers, it is necessary to reanalyze the acoustic generation mechanism of the entire structure of the bridge-sound barriers coupled system and combine it with the propagation mechanism of various sound sources.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501408
       
  • Null Phase Assumption-Based Technique for Constructing the Target Model of
           Seismic Irregularity on High-Speed Railways

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      Authors: Jian Yu, Wangbao Zhou, Lizhong Jiang, Xiang Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      High-speed railways are “lifeline projects” that shoulder the heavy responsibility of transporting relief supplies and medical forces for the first time after earthquakes. To ensure the train’s safety after earthquakes, it is of great urgency to ascertain a post-earthquake speed threshold. To that end, a target model for seismic irregularity emerges as a key parameter. In this paper, a null phase assumption-based technique for the mutual conversion between evolutionary power spectral density and non-stationary signal was proposed. Taking a high-speed railway track-bridge system as the research object, the target model of seismic irregularities was constructed based on the proposed technique. The rationality of the target model of seismic irregularities was verified, and the construction parameter settings were discussed. Moreover, a simplified frequency-domain fitting method for the target model of seismic irregularities was proposed based on the spectral decomposition theory. According to the research findings, the null phase assumption-based technique is capable of performing interconversion between seismic irregularity and its evolutionary power spectral density with satisfactory accuracy. It is recommended to set the minimum number of seismic irregularities, spatial sampling interval, hop size, and length of window function as 50, 0.25[math]m, 1, and 40 to 100, respectively.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S021945542550141X
       
  • Free Vibration of Ogival Circular Arch

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      Authors: Joon Kyu Lee, Byoung Koo Lee, Hee Min Yoon, Jong Cheon Lee
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study aims to analyze the free vibration of an ogival arch in which two symmetrical arched shapes are discontinuously met at the mid-arc. Differential equations governing the free vibration of an ogival circular arch were derived, where the rotatory inertia and shear deformation effects are included. The governing equations were numerically solved to calculate natural frequencies and mode shapes. In numerical solution methods, the symmetric and anti-symmetric boundary conditions at the mid-arc were focused rather than the boundary conditions of supported end due to the discontinuity of the mid-arc. For the first time, the free vibration problem for discontinuous arches, such as ogival arches, is solved in this study. Calculation results of this study for natural frequencies are compared well with those of the finite element method. The effects of various arch parameters on natural frequencies were highlighted and discussed in detail.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-24T07:00:00Z
      DOI: 10.1142/S0219455425501494
       
  • Parameter Tuning and Positioning Strategy of VD and TMD Joint Control
           System for Multi-Modal Vibration of Stay Cables

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      Authors: Shengli Li, Wei Gou, Wudi Gao, Jiaxiang Zhang, Xidong Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Stay cables are becoming slender and their fundamental frequencies are becoming lower with the span of bridges increasing, thus leading to the occurrence of multi-modal vibration under various excitations. As a simple and effective strategy for cable vibration mitigation, the external damper is widely used in practice. However, one damper normally can target only fewer modes and poses limited effects on the control of multi-modal vibration. This paper proposed the use of a joint control system combining a viscous damper and a tuned mass damper for mitigating the multi-modal vibration of stay cables, followed by the optimization methodology of tuning and positioning. The control performance of the joint system was evaluated by numerical simulations. The feasibility of the joint control system was validated by analyzing the results of the comparative study, therefore providing a possible solution to multi-modal and high-modal vibration of stay cables.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-17T07:00:00Z
      DOI: 10.1142/S0219455425500920
       
  • Crashworthiness Analysis of Self-Similar Nested Hierarchical Hexagonal
           Tubes

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      Authors: Fuxian Zhang, Fuyun Liu, Xiaolin Deng, Yuwen Chen, Zhenzhen Cai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To enhance the crashworthiness of thin-walled structures, this study proposes a self-similar nested hierarchical hexagonal tube. This innovative design incorporates the hierarchical technique into the structural configuration of hexagonal thin-walled tubes. Numerical analysis, conducted using a validated finite element model, reveals that the proposed self-similar nested hierarchical hexagonal tube (SNHHT) significantly enhances energy absorption compared to traditional hexagonal tubes, maintaining consistent wall thickness and mass conditions. Particularly noteworthy is the improvement in energy absorption indexes under the same mass condition, with SNHHT-4 demonstrating enhancements of up to 76.45% and 86.84% in energy absorption and crushing force efficiency, respectively, while concurrently achieving a 4.11% reduction in initial peak crash force. Subsequently, a parametric study exploring wall thickness, shape factor, and various rib thicknesses was performed to investigate structural crashworthiness. Finally, employing the simplified super-folded element method, the theoretical formulation of mean crushing force was derived, and its accuracy was validated through numerical simulations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-17T07:00:00Z
      DOI: 10.1142/S0219455425501196
       
  • Effect of Amplifier on Vehicle Scanning Method Concerning Pitching
           Responses

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      Authors: Judy P. Yang, Ching-Chien Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A vehicle–bridge system with a tunable amplifier is proposed to enhance the resolution of frequency identification in the vehicle scanning method (VSM), with a particular interest in the wheel-center spectra to account for pitching responses. Both semi-analytical and finite element formulations are established. The viability of the proposed amplifier–vehicle–bridge system is demonstrated in consideration of bridge types and boundary conditions, damping effect, and pavement irregularity. The major findings include the following: (1) The tunable feature of the amplifier enhances the visibility of higher-order bridge frequencies in its spectrum. (2) The vehicle responses can be removed in the cancellation conditions of the amplifier while the resonance conditions of the amplifier are not affected by vehicle damping under harmonic excitation. (3) The shifted higher-order bridge frequencies are distinctly shown in the wheel-center spectra, indicating the potential use of pitching responses in VSM. (4) The pitching responses have shown that the front-wheel spectrum has a higher resolution than the rear one, as influenced by the driving direction.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425410020
       
  • Seismic Assessment of Self-Centering Rocking Braced Systems with Story
           Energy Dissipation

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      Authors: Farzad Raeiszadeh, Mohammad Reza Mansoori, Abdolreza S. Moghadam, Armin Aziminejad
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Self-centering rocking braced (SCRB) system provides enhanced seismic performance and reduced post-earthquake residual drift. However, the effect of higher modes is controversial, affecting shear demands and bending moments in the structure. This functional deficiency is addressed by developing SCRB frames equipped with buckling-restrained columns (BRCs) and buckling-restrained braces (BRBs), performing as exchangeable fuse frames. The system consists of external columns branching off from the main core and connected to it via butterfly-shaped fuses, and BRC and BRB are incorporated into the core at four different height levels to be compared with conventional SCRB as the baseline. Three sets of 12-, 16- and 20-story structures are numerically developed in OpenSees finite element framework with regard to geometrical and material nonlinearities, making a total of 12 SCRB prototypes. The suit of 22 ground motions used in FEMA P695 was scaled to DBE and MCE hazard levels and applied to the structures. Results indicate the capability of the new system in reducing the destructive effects of higher modes, especially in the case of a fuse frame located in the middle of the height. In addition, the core moment and shear force largely reduced, almost 60%, in higher positions of the fuse frame, while those configurations led to large residual drift at the restrained level. However, all structures met the DBE-level 2% drift target. Moreover, increasing structural height nearly reduced seismic demands and increased response reductions. Overall, the system demonstrated acceptable performance in terms of high capacity for energy absorption.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425500889
       
  • Study on Structure-Borne Noise Characteristics of Long-Span Steel Truss
           Bridge in Urban Rail Transit

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      Authors: Taoping Bai, Lin Liang, Xiaojun Qi, Kunchun Zhang, Mingyang Li, Zhifei Jin
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The application of long-span steel bridge in urban rail transit is becoming more and more extensive, but the structure-borne noise of steel bridge induced by passing train is also prominent. Research on the structure-borne noise problem of long-span steel bridge in urban rail transit has positive significance in promoting the sustainable development of steel bridge, and improving the quality of sound environment along rail transit. In this work, dynamic receptance principle, finite element method and statistical energy method are combined to establish the structure-borne noise prediction model of the long-span steel bridge, and the rationality and validity of the model are verified based on field measurement results. Based on the prediction model, the noise radiation characteristics of large-span steel truss bridge in urban rail transit are studied, and the following conclusions are drawn: The bridge deck has the strongest acoustic contribution ability, with the contribution rate of 33–44%, followed by the longitudinal web and transverse web, with the contribution rate of 23–30%, followed by the truss chord, with the contribution rate of 5–8%, and the truss web, longitudinal wing and transverse wing have weak contribution ability, with the contribution rate of less than 2%. The acoustic radiation efficiency of steel truss bridge components reaches its peak at the critical frequency, and the critical frequency is determined by the thickness of steel bridge plate components when the material parameters are fixed. Under ordinary track structures, the middle-to-high frequency noise distribution characteristics of large-span steel truss bridge structure are obvious. Damping pad floating slab track can effectively suppress the high-frequency noise of steel bridge, and the overall sound level can be reduced by about 11–14[math]dB.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425501020
       
  • Dynamic Analysis Strategy of Generalized Deployable Units via NCF-IGA with
           Force Constraint

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      Authors: Yuancheng Ma, Tuanjie Li, Hangjia Dong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Space deployable mechanisms typically employ modular designs, where each unit that can be independently deployed is defined as a generalized deployable unit (GDU), typically consisting of rigid components, flexible components and generalized kinematic pairs. Given the high-performance demands of spatial transmission mechanisms, generalized kinematic pairs frequently integrate flexible factors like torsion springs and flexible hinges, which control the motion according to the attitude and position of the component. In this investigation, a new modeling and solution strategy for rigid-flexible coupled dynamics is established by combining NCF and IGA. It can not only accurately describe the large deformation and large rotation of flexible components, but also consider the influence of flexible factors in the kinematic pairs. The rigid components are modeled by the Natural Coordinate Formula (NCF), and the flexible components are discretized in the inertial coordinate system using spline curves in Isogeometric Analysis (IGA). The intermediate reference coordinates were integrated into the NCF-IGA framework, overcoming the boundary constraints between B-spline and NCF elements, and the geometric constraint equation of the kinematic pair was established. Subsequently, this paper proposes the concept of force constraint in controllable deployable mechanisms. Based on the force constraint equation, the mechanical model of flexible joints is established. The dynamic equations of GDUs are derived considering both geometric and force constraints, and generalized-[math] method is introduced to solve the equations. Finally, three numerical examples are provided to illustrate the applicability and superiority of the proposed method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425501068
       
  • Dynamic Characteristics of M-Shape Metal Rubber-Coated Pipeline System:
           Numerical Modeling and Experimental Analysis

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      Authors: Yilin Chen, Shaoxiang Ge, Jianchao Liu, Xiaochao Chen, Xin Xue
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      As a high-temperature resistant damping material, reducing vibration by coating with M-shape metal rubber (MMR) in a pipeline system is a promising solution due to its energy dissipation induced by micro dry friction between metallic wires. The main challenge for dynamic calculation and performance evaluation of elastic-porous metal rubber (MR) is derived from the intricate spatial network structure. In this work, the dynamic properties including acceleration admittance and insertion loss of the MMR-coated pipeline system were conducted by numerical simulation and experimental analysis. The constitutive models used to characterize hysteresis phenomena, including Yeoh and Bergström–Boyce models, were identified with different density parameters and adopted for steady-state dynamic numerical analysis. The sine sweep frequency test was conducted to verify the accuracy of the developed numerical model. The results indicate that the maximum error of stress–strain curve between numerical prediction and experimental measurement is 10.7%. In the frequency range of 0–1 500[math]Hz, the insertion loss of the MMR-coated pipeline system is positively correlated with the density of MMR, as opposed to the coating distance of pipeline clamps and the influence of excitation force is minimal. Furthermore, the error of dynamic response of the pipeline system in low frequency between the experiment and simulation is 4.7%, indicating that the accuracy of the hysteresis model in predicting the dynamic characteristic of MR materials is effective.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425501123
       
  • Free Vibration of Thermally Loaded FG-GPLRC Nanoplates Integrated with
           Magneto-Electro-Elastic Layers in Contact with Fluid

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      Authors: Pouyan Roodgar Saffari, Chanachai Thongchom, Peyman Roodgar Saffari, Jintara Lawongkerd, Suraparb Keawsawasvong, Teerapong Senjuntichai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This work investigates the free vibrations of innovative thermally loaded nanoplates constructed by integrating magneto-electro-elastic (MEE) layers with functionally-graded graphene platelet-reinforced composite cores (FG-GPLRC) and accounting for viscous fluid interactions. An advanced multiphysics model is developed using the Navier–Stokes equations to capture fluid structure coupling effects, Halpin–Tsai, and the rule of mixtures micromechanics to predict the non-uniform effective properties, third-order shear deformation plates theory (TSDPT) to incorporate thickness stretching, and the nonlocal strain gradient theory (NSGT) to characterize size dependencies. The Galerkin technique is used to solve the governing equations, which are derived from the Hamilton’s principle. Parametric analyses quantify the influences of fluid depth, temperature fluctuations, temperature profiles, nonlocal and strain gradient parameters, electric and magnetic potentials, graphene distribution patterns, graphene weight fractions, and boundary conditions on the vibration response. The outcomes of this study provide design guidelines and predictive tools enabling active vibration control systems for next-generation thermally-loaded nanocomposite structures with widespread applications from aerospace vehicles to nanoelectronics.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425501135
       
  • Dynamic Analysis of Functionally Graded Sandwich Doubly Curved Nanoshells
           Using Variable Nonlocal Elasticity Theory

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      Authors: Mahdi Dadashi, Morteza Karamooz Mahdiabadi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Sandwich nanoshells consisting of functionally graded materials (FGMs) offer promise in aerospace, energy and biomedical applications due to their tunable properties. However, a comprehensive understanding of the vibration behavior of such shells is lacking. This work develops an efficient analytical model to study free vibration of sandwich nanoshells with three FGM configurations: FGM face-sheets and metal core (Type A), FGM face-sheets and ceramic core (Type B), and FGM core and face-sheets (Type C). A doubly curved shell geometry representing spherical, hyperbolic–parabolic and cylindrical shells in addition to flat plates is considered. Effective material properties of nanolaminates are computed using a volume fraction-based model. First-order shear deformation theory and modified nonlocal elasticity theory with variable nonlocal parameters are employed to derive the governing equations. Hamilton’s principle is used to obtain the equations of motion. Navier’s solution technique analytically solves the equations for simply supported boundary conditions. Accuracy is validated through comparisons with literature results. Parametric studies analyze the influence of thickness ratio, material gradation, nonlocal parameter, and shell type on frequencies. Results show that Type A configuration yields the highest frequencies. Dimensionless frequency decreases with increasing nonlocal parameter and side-to-thickness ratio. The model provides design insights into vibration behavior of such nanosandwich structures with potential applications in nanodevices and energy harvesting.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-08T07:00:00Z
      DOI: 10.1142/S0219455425501226
       
  • Stability Tests and Simulations of Fold-Fastened Multi-Cellular Steel
           Walls

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      Authors: Jing-Zhong Tong, Sheng-Jie Duan, Xiong Yang, Chao-Qun Yu, Gen-Shu Tong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To further expand the application range of cold-formed steel (CFS) members in practical engineering, a novel fold-fastened multi-cellular steel wall (FMSW) was introduced and investigated in detail. The FMSWs were mechanically connected by the hook-shaped and groove-shaped regions at both ends of the single limb members, by which the assembly efficiency was greatly improved. In this paper, a total of 10 slender FMSW specimens were subjected to axial compressive loadings, and the failure mode, load–vertical displacement curves, load–lateral displacement curves, and bearing capacity of the specimens were obtained. According to the experimental results, the development and failure modes of the local-global interactive buckling of FMSWs were revealed. All specimens experienced local buckling initially, followed by global buckling, and ultimately interactive buckling. The load–displacement curves exhibited similar trends, being characterized by three stages: the elastic stage, the elastic-plastic stage, and the descending stage. Furthermore, the nonlinear ascending segment was short, indicating that the failure was sudden. By comparing the bearing capacities among specimens, it was recognized that the ultimate resistance of FMSWs could be obtained by the superposition of the cells, and the bearing capacity was rarely affected by the height-to-thickness ratio. Based on the experimental results, refined finite element (FE) models were established and the accuracy and effectiveness of the modeling method were verified. Valuable reference could be provided by the research achievements of this paper for the subsequent research of CFS built-up members and their application in practical engineering.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501032
       
  • Analytic Solution and Benchmark Results for the Free Vibrations of Thin
           Shallow Shells with Rectangular Planform

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      Authors: A. Deutsch, M. Eisenberger
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this work, a new analytic solution for vibrations of shallow shells is presented. The equations of motion consist of three coupled partial differential equations. Solutions to such complex coupled equations were only available for the Navier and Levy cases of boundary conditions, which is a small part of the scope of the problem. A superposition of two solutions enables to satisfy both the equations of motion and any combination of boundary conditions. For isotropic square shallow shell, there are 9[math]316 different combinations of support conditions. For isotropic rectangular shell or square orthotropic shell, the number is 18[math]496. These numbers apply for a single type of curvature and aspect ratio. For all these a general solution is derived. The functions for the solution are obtained by using carefully chosen series that solve the coupled partial differential equations of motion for in-plane and out-of-plane deformations for all possible combinations of edge conditions. The number of terms in the series is taken such that convergence is assured to the number of digits as shown. Examples of the new solutions are given and compared with available solutions in the open literature.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501147
       
  • Mechanical Characteristics of Bistable Inflatable Folding Beam Structure

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      Authors: Liang-Jie Zhao, Bo-Hua Sun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Folding structures are easy to transport and deploy, and they have promising engineering applications. A multi-stable folding system with a high deployment efficiency can be obtained by combining the inflatability of pneumatic structures with the multi-stability of origami structures. With the triangular unit as the basic element, an inflatable-driven folding beam structure with folding and unfolding bistable characteristics was designed, and then the mechanical characteristics of the designed beam were analyzed through the finite element method. The results showed that after the designed beam was inflated, the maximum stress appeared at the intersection of multiple creases between adjacent cavities, and with the increase in the fluid cavity pressure, the increase rate of the crease stress was four times that of inner wall stress. It was easier to break the energy barrier of the bistable state by applying a longitudinal load perpendicular to the crease direction of the design beam than by applying the transverse load along the crease direction. Therefore, when the designed beam was subjected to bending deformation, its bearing capacity was not significantly affected by the change of the fluid cavity pressure. However, when the designed beam was compressed under a longitudinal load, the fluid cavity pressure increased by 10[math]kPa, and the longitudinal load-bearing capacity was increased by about 12.8%. Finally, increasing an inner angle of a triangle within the limits will enhance the load capacity of the design beam. It is difficult to improve the proposed beam load capacity by increasing the sheet width.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501172
       
  • Nonlinear Effects of Mechanical and Aerodynamic Damping on a
           Motion-Amplitude-Dependent VIV Model

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      Authors: Kai Qie, Zhitian Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Based on VIV time histories growing from still to limit cycle oscillations, the motion-amplitude dependence of the VIV loading model is determined. Energy-trapping properties corresponding to the entire process of motion evolution are described by the model parameters. The influence of nonlinear mechanical damping on the VIV loading model parameter is analyzed. Prediction of VIVs under higher mechanical damping ratios is performed by the identified VIV model. The results show that, while the model parameter [math] varies drastically with the motion amplitude, the aerodynamic damping involves gently and monotonically towards a final value corresponding to an LCO state. Neglecting the nonlinearities in mechanical damping would result in significant deviations in model parameters and predicted VIV responses. By comparing the traditional fixed-[math] model with the proposed nonlinear-[math] model, it is found that the VIVs predicted by the former are about 1.5[math]3.0 times those predicted by the latter or tested, which underlies the necessity of consideration of motion-amplitude-dependence of an aerodynamic model.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501202
       
  • A Low-Frequency Vibration Isolator Using Permanent Magnets and Kresling
           Origami Structure

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      Authors: Tianyu Chen, Bo Tang, Ming Xu, Kai Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The performance deterioration behavior resulting from vibrations in various mechanical systems, such as precision instruments, has long plagued engineers. One efficient approach for vibration protection is to use a quasi-zero stiffness (QZS) structure, which has high static and low dynamic characteristics. In this study, a low-frequency vibration isolator using permanent magnets and a Kresling origami structure is proposed that works for both torsional and/or axial excitations. The responses to both deterministic and random excitations were studied by establishing dynamic equations. The results show that the coupling of the axial and torsional motions results in an additional mass, which reduces the frequency and improves the low-frequency performance of the QZS structure. Force transmissibility was used to demonstrate the effects of the QZS structure. Compared with the degenerated linear system, the force transmissibility was lower over a wider frequency range. The ratio of the mean–square force of the QZS structure to that of a degenerate linear system under random excitation was also investigated. For weak Gaussian white noise, the QZS structure is effective and suitable for varying frequencies. However, it does not work for strong excitations. The results also show that the system damping aids in vibration isolation. We believe that our work provides a new method for designing a QZS structure using origami structures for multidirectional excitations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501214
       
  • Harvesting Vibration Energy of a Longitudinally Vibrating Rod within a
           Width Frequency Band by Designing Variable Stiffness Equipment

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      Authors: Xiuyi Nie, Di Li, Haijian Cui, Mingfei Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Structural vibrations are widespread in various structures and contain abundant vibration energy. While numerous studies have focused on harvesting vibration energy from beams, plates, and cylinders, few have addressed the longitudinal vibration energy harvesting from rods, thus presenting challenges in achieving broadband vibration energy harvesting from longitudinally vibrating rods. Considering the engineering context and existing limitations, this study investigates the broadband harvesting of longitudinal vibration energy from a rod system. The study introduces a longitudinal vibration energy trapping mechanism (LVETM), with variable stiffness equipment as its key component. It validates the theory for broadband harvesting of longitudinal vibration energy in the rod system using variable stiffness support. The stiffness coefficients of the LVETM can be effectively controlled by altering its state, thereby laying the foundation for the theory of broadband harvest of longitudinal vibration energy in rod systems. Additionally, the output voltage responses from the longitudinally vibrating rod system indicate a region for broadband vibration energy harvesting. Within this region, controlling the states of LVETM can enhance the output voltage responses of the longitudinally vibrating rod. Overall, this research presents an effective method for broadband harvesting of vibration energy from longitudinally vibrating rods.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-06T07:00:00Z
      DOI: 10.1142/S0219455425501238
       
  • Exact Eigensolutions of Two-Dimensional Laminated Panel Flutter Based on
           Mindlin Plate Theory and the First-Order Piston Theory

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      Authors: Dezhuang Pan, Yufeng Xing
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The panel flutter analysis considering the shear deformation is performed with a particular focus on the exact eigensolutions and the energy transfer. According to Mindlin plate theory and the first-order piston theory, this work obtains the exact eigensolutions of two-dimensional (2D) panel flutter at supersonic speeds. The boundary conditions (BCs) considered include: two edges are simply supported (SS), two edges are clamped (CC), and two edges are clamped and free (CF) respectively. Using the obtained exact eigensolutions, the relations of the kinetic energy, the potential energy and the work done by aerodynamic force are examined for the states of divergent vibration and periodic vibration. Besides, the coupling effect of shear deformation and aerodynamic damping on flutter frequencies is also revealed, and the present results are compared with those of the Galerkin method and the 2D Kirchhoff panel.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-01T07:00:00Z
      DOI: 10.1142/S0219455425500890
       
  • Crashworthiness Analysis of Bio-Inspired Fractal Plant Stems Multi-Cell
           Circular Tubes

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      Authors: Zhenzhen Cai, Xiaolin Deng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A novel structure resembling plant stems, termed bio-inspired fractal plant stems multi-cellular circular tubes (BFPMC), was developed by incorporating fractal plant stem characteristics into smaller circular tubes within larger ones. The crashworthiness of this structure under axial impact was investigated using a validated LS-DYNA finite element model. The energy absorption performance of BFPMC tubes, varying in the number of branches, fractal orders, and inner circular diameters, was numerically studied. The numerical findings reveal a 19.27% increase in specific energy absorption (SEA) for BFPMC with [math][math]mm compared to [math][math]mm, indicating that filling a single circular tube can enhance the structure’s impact resistance. Subsequently, structural parameters conducive to excellent energy absorption characteristics were determined for various combinations of a number of branches, fractal order, and inner circle diameter parameters. These results offer valuable insights for designing multi-cellular double tubes with high energy absorption efficiency.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-01T07:00:00Z
      DOI: 10.1142/S0219455425500919
       
  • Transfer Learning-Based Structural Damage Identification for Building
           Structures with Limited Measurement Data

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      Authors: Xutong Zhang, Xinqun Zhu, Yang Yu, Jianchun Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Structural damage detection is crucial for ensuring the safety of civil building structures in operational environments. Recently, deep learning-based methods have gained increasing attention from engineers and researchers. The performance of conventional deep learning methods for structural damage detection relies on a large number of labeled training datasets. However, it is difficult or/and impossible to obtain sufficient datasets to cover various damage scenarios for in-service structures. A little research has been conducted to identify both the damage severity and location with limited labeled measurement data. A novel transfer learning-based method for structural damage identification with limited measurements has been proposed utilizing frequency response functions (FRFs) as the input. The real structure is regarded as the target domain and its numerical model is as the source domain. The samples for various damage scenarios are generated using the numerical model, and a designed deep convolutional neural network (CNN) is pre-trained. The knowledge of the pre-trained network is transferred to identify the damage location and severity of the real structure using limited measurement data. Numerical and experimental studies have been conducted on a three-story building structure to verify the performance of the proposed method. To understand transfer learning and model interpretability, the t-SNE feature visualization is adopted to show the feature distribution changes during transfer learning. Numerical and experimental results show that the proposed approach outperforms conventional CNN models, and it is effective and accurate in identifying structural damage location and severity in real structures with limited measurement data.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-01T07:00:00Z
      DOI: 10.1142/S0219455425500932
       
  • The Effect of Hyperelasticity and Nonlinearity on the Dynamic Behaviors of
           Hyperelastic Functionally Graded Beams on Nonlinear Elastic Foundation

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      Authors: Jun Chen, Wenchao Qu, Chao Ye, Zinan Zhao, Huiming Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Hyperelastic functionally graded materials have a wide range of application prospects in soft robotics and biomedical fields. This paper investigates the nonlinear free and forced vibrations of a hyperelastic functionally graded beam (HFGB) based on higher-order shear deformation beam theory. The geometrical nonlinearity is considered by using the von-Kármán’s nonlinear theory. The three-material-parameter free energy function named as Ishihara model is employed to characterize the hyperelastic material. The power-law gradient form along the thickness direction is adopted. The HFGB is resting on the elastic foundation. The Winkler, Pasternak and nonlinear stiffness coefficients are considered. The time-harmonic external force is applied to the HFGB. The nonlinear governing equations for the vibration of the HFGB are derived by using Hamilton’s principle, and are subsequently transformed into ordinary differential equations via Galerkin’s method. The nonlinear free vibration and primary resonance of the HFGB are investigated analytically by employing the extended Hamiltonian method and multiple scales method, respectively. The results indicate that the power-law index, slenderness ratio, material properties, and elastic foundation parameters have significant influences on the nonlinear frequency of free vibration as well as the frequency–response and force–response curves of forced vibration. The phase plane method is employed to analyze the system’s stability states under various excitation amplitudes. The relative error between the results of the current computational model and the published literature is less than 0.1 percent.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-01T07:00:00Z
      DOI: 10.1142/S0219455425500968
       
  • A Frequency Identification Approach for Damaged Heavy-Haul Railway Bridge
           with Bogie Accelerations

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      Authors: Jiaqi Shi, Hongmei Shi, Nan Zhang, Jianbo Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Bridge structural health monitoring (BSHM) is extensively employed to assess whether bridge damage exceeds maintenance limits and helps maintenance decision-making. Frequency identification is an essential part of BSHM, which utilizes the first-order modal frequency as an evaluation indicator of bridge health status. This paper proposes a method for bridge damage identification based on extracting the first-order modal frequency of the bridge from dynamic responses of vehicle bogies. Firstly, the feasibility of extracting bridge modal frequency from bogie accelerations is theoretically deduced via a vehicle–bridge interaction model. The result indicates that the bogie accelerations encompass three frequency components, namely vehicle driving frequency, vehicle pitching frequency and bridge first-order modal frequency. Then, a multi-domain conjoint analysis method incorporating the time domain, frequency domain and time–frequency domain is proposed to extract the first-order frequency of damaged bridge from bogie accelerations. By defining a damage sensitivity index of the sliding window, the time-domain sensitive boundaries of bogie acceleration to bridge damage are pinpointed. Leveraging prior knowledge of the bridge modal frequency range, the frequency-domain sensitive boundaries bogie acceleration to bridge frequency are determined. On this basis, the sensitive region of bogie acceleration to bridge frequency can be precisely localized in the Hilbert Huang transform spectrum, ultimately identifying bridge frequency through searching local maximum instantaneous energy points within this region. Finally, comprehensive experiments, considering different vehicle speeds and track spectra scenarios, are carried out to investigate the effectiveness and robustness of the proposed method. The results affirm the performance of the method to accurately identify the first-order modal frequency of the damaged bridge, further underscoring the promising prospect of on-board BSHM.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-06-01T07:00:00Z
      DOI: 10.1142/S0219455425501007
       
  • Dynamic Analysis of the Hangers in High-Speed Railway Arch Bridge Based on
           Train–Bridge Interaction Simulation and Field Measurement

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      Authors: Huile Li, Huan Yan, Gang Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The hangers represent the crucial load-bearing component of arch bridges and are susceptible to dynamic vehicle load. However, little effort has been made to carry out dynamic analysis of arch bridge hangers under high-speed train loads. This paper presents an investigation of the dynamic behavior of the arch bridge subjected to high-speed train with emphasis on the flexible hangers, using train–bridge interaction simulation and field measurement data. Coupled train–bridge system model composed of three-dimensional train model, bridge model, and wheel–rail interaction model is established to account for hanger transverse vibration, spatial train loading, and track irregularity excitation, among others. Vibration data of bridge components including the hanger are measured through field test on a typical high-speed railway tied-arch bridge. A total stress-based dynamic amplification factor is subsequently proposed to describe the effect of hanger transverse vibration. The influence of significant parameters such as train speed and track irregularity on the dynamic effects of hangers is examined by the experimentally validated train–bridge interaction model. It is found that the dynamic responses of the hangers are considerably different from bridge global responses. In-plane and out-of-plane transverse vibrations of the hanger result in a large increase in the hanger dynamic effects which prove to be sensitive to train speed, track irregularity, train loading position, etc. Moreover, the dynamic amplification factor formula in the current high-speed railway code may not be sufficient to characterize the dynamic amplification of hangers under operating conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-25T07:00:00Z
      DOI: 10.1142/S0219455425410019
       
  • Buckling Behavior of Laminated Shell Panels Under Linearly Variable Edge
           Load

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      Authors: Gayatri Patel, Leena Sinha, Amar Nath Nayak
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper reports a detailed numerical investigation on the buckling aspects of laminated composite shell panels of three forms (cylindrical, spherical and hyperbolic paraboloid) with five support conditions exposed to linearly varying in-plane edge load employing eight nodded isoparametric finite element formulation. The impacts of different parameters including ply orientation, load factor, shell forms, aspect ratio, modulus ratio, curvature ratio, width-to-thickness ratio and angle of lamination on the buckling load of shell panels are examined. It is found that the various parameters addressed in this study have a remarkable impact on the buckling phenomena of laminated composite shell panels. Further, a comparison is made showing the effects of five types of compressive edge loads like uniform, triangular, parabolic, partial edge load and point load on the buckling phenomena of laminated shell panels with respect to five support conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-25T07:00:00Z
      DOI: 10.1142/S0219455425500907
       
  • Structural Vibration Identification in Ancient Buildings Based on
           Multi-Feature and Multi-Sensor

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      Authors: Yulong Yang, Chen Qian, Yumiao Zhang, Jiafu Pan, Jintao Wang, Yang Tan, Jiawei Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Ancient buildings have strict standards for vibration control. Effectively identifying vibration types and controlling construction vibrations during construction activities is advantageous to the structural safety of ancient buildings. This study is based on an analysis of vibration data from the top, foundation, and bedrock of the White Pagoda in Hangzhou, Zhejiang province, which is an ancient building. Considering the surrounding construction and wind environment, this study focuses on analyzing the data features of tower vibrations under three types of structural vibration. We propose a support vector machine (SVM) vibration identification method that incorporates multi-feature parameters and multi-sensor signal correlation. This method effectively identifies the source of structural vibration by distinguishing between typical wind-induced vibrations, typical construction vibrations, and typical mixed vibrations. The application of this method could guide construction activities and mitigate the safety impacts of construction and mixed vibrations on historical building structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-25T07:00:00Z
      DOI: 10.1142/S0219455425500944
       
  • Effect of Thickness Stretching on Bending, Buckling, and Free Vibration of
           Functionally Graded Porous Beams

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      Authors: Zhuangzhuang Wang, Liansheng Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, the bending, buckling, and free vibration of functionally graded porous (FGP) beams are studied based on two beam theories (with or without considering thickness stretching, respectively). The effect of thickness stretching is obtained by comparing the results of the two theories. Two symmetrical distributions and one asymmetrical distribution of pores are considered. Both Young’s modulus and mass density of the FGP beams are in gradient variation in the thickness direction. The governing equations are constructed using Hamilton’s principle. The analytical solutions are obtained by Navier’s method. The effects of slenderness ratios, pore distribution, porosity and thickness stretching on FGP beams have been investigated. The results show that the inhomogeneity of FGP beams in the thickness direction is positively correlated with the effect of thickness stretching.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-25T07:00:00Z
      DOI: 10.1142/S021945542550097X
       
  • Nonlinear Energy Harvesting From a Base Excited Size-Dependent
           Flexoelectric Nanostructure with Off-Center Rigid Tip Mass Subjected to
           Axial Pulsating Excitation

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      Authors: Chandan Pandey, Pravesh Kumar, Barun Pratiher
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study explores the incorporation of flexoelectricity and size-dependence effects in electricity harvesting from a novel nanostructure. This nanostructure, featuring a cylindrical-shaped rigid tip mass, is stimulated at the base with axial pulsating excitation. Designed with a nanobeam material, the energy harvester accounts for structural nonlinearity, flexoelectricity, and the presence of an off-center rigid mass, operating under multiple excitations. The eigenanalysis is employed to delve into the dynamic characteristics of the system, providing engineers with insights to identify safe operating regions and operational constraints. Additionally, perturbation techniques are utilized to estimate steady-state voltage and power characteristics, with a focus on maximizing voltage and power generation. The study underscores the impact of size dependence on nanoscale design, flexoelectricity, asymmetric tip mass, and various excitation parameters within a constrained operating range. Analysis reveals how saddle-node and pitchfork bifurcations can disrupt energy harvesting performance and suggests strategies for mitigating these issues by adjusting operational parameters. Moreover, the study emphasizes the significant role of the off-center rigid tip mass in energy estimation compared to conventional microstructure-based energy harvesters. Analytical findings are rigorously validated against numerical results under different resonant scenarios, showcasing the accuracy of the analytical approach in capturing nonlinear sources and optimizing energy harvesting from nanostructures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-23T07:00:00Z
      DOI: 10.1142/S0219455425500841
       
  • A Novel Bayesian Empowered Piecewise Multi-Objective Sparse Evolution for
           Structural Condition Assessment

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      Authors: Zhenghao Ding, Sin-Chi Kuok, Yongzhi Lei, Yang Yu, Guangcai Zhang, Shuling Hu, Ka-Veng Yuen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a novel Bayesian empowered piecewise multi-objective function is developed, in which a traditional objective function is applied to realize the rough optimization in the first stage to determine the approximate results. Then, a sparse Bayesian learning-based objective function is applied to realize refined optimization with the obtained approximate results in the second stage. On the other hand, considering the sparsity of the structural damage identification, two simple but effective calculation frameworks, the colony initial sparsification and elite clustering framework, are integrated into the evolution, making the algorithm adaptable to handle the defined sparse optimization problem. Therefore, the proposed calculation framework is more efficient and robust while no initial conditions are needed. We will carry out a numerical example on a truss and an experimental validation on a fixed-end beam with a single-sensor measurement system to verify the method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-21T07:00:00Z
      DOI: 10.1142/S0219455425501019
       
  • Identification Methods for Modal Parameters of Track Structures and Their
           Application Status and Prospects

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      Authors: Bolun An, Pu Wang, Fengshou Liu, Guang Yang, Chaozhi Ma, Junqi Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Rail transit’s wheel–rail system periodically encounters defects such as wheel polygons, rail corrugation, and rail fastener failure, which are intricately linked to the modal parameters of track structures. Identifying these modal parameters is essential for refining wheel–rail dynamics models, understanding track defect mechanisms, and defect detection. This study reviews the current methodologies for identifying track structure modal parameters, emphasizing their significance in track engineering. It categorizes various identification techniques, examines their development, and highlights their application in updating track dynamics theoretical models. The relationship between track modal parameters and wheel–rail defects is discussed, alongside a summary of modal parameter-based defect remediation strategies globally. The paper also evaluates the current state of defect identification research utilizing track modal parameters. In the “prospects” section, three forward-looking research avenues are proposed. These approaches are poised to streamline and improve the efficiency of modal parameter extraction, marking potential breakthroughs in the field.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-17T07:00:00Z
      DOI: 10.1142/S0219455425300010
       
  • Nonlinear Dynamic Properties of Rigid–Elastic–Liquid Coupled Ball
           Bearings Considering External Load Excitation

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      Authors: Yan Li, Haisheng Yang, Yongcun Cui, Sier Deng, Wenhu Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a novel dynamic model of a ball bearing based on rigid–elastic–liquid (REL) coupling structure considering external load excitation is established, and the dynamic response of its outer ring under external load excitation is examined. First, the differential equation of the journal motion (i.e. the outer ring) is derived based on Newton’s law, and the oil film force induced by the REL coupling structure is determined by using the central finite difference method, planar bending theory of thin ring, and Simpson’s rule. Further, the fourth and fifth-order variable step length Runge–Kutta method is used to solve the kinematic differential equation. Second, the dynamic characteristics of the outer ring of the bearing under different speeds and elastic support structural parameters are examined. Finally, the feasibility of the theoretical model is verified through experiments. The results show that compared with the traditional squeeze film damper (SFD) system, the ball bearing with REL coupling structure is more stable, and the vibration damping effect is better under higher bearing speed, lower squirrel cage stiffness, and smaller elastic ring flexibility coefficient. The above findings provide useful insights into the dynamic characteristics of REL coupled ball bearings under unbalanced excitation, which can serve as a reference for the optimization design of such ball bearings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-15T07:00:00Z
      DOI: 10.1142/S0219455425500853
       
  • Model-Free Optimal Vibration Control of a Nonlinear System Based on Deep
           Reinforcement Learning

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      Authors: Jiyuan Jiang, Jie Tang, Kun Zhao, Meng Li, Yinghui Li, Dengqing Cao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Optimal control of nonlinear vibration requires precise knowledge of the system and the solution to Hamilton–Jacobi–Bellman (HJB) equation. However, in practical engineering applications, acquiring precise system parameters poses challenges, and the analytical solutions for the HJB equation are difficult to obtain. In this paper, two reinforcement learning algorithms, Twin Delayed Deep Deterministic Policy Gradient (TD3) algorithm and Soft Actor-Critic (SAC) algorithm, are employed to train neural network-based optimal controllers for the van der Pol vibration system in the presence of unknown system parameters. To validate their performance, the controllers undergo testing in a series of experiments, including assessments of free vibration, frequency sweep excitation, and Gaussian noise excitation. The results indicate that both the TD3-trained and SAC-trained neural network-based controller are capable of proficiently suppress the vibration of the van der Pol oscillator. Additionally, these two model-free controllers can approximate the optimal control law which solved based on the dynamic model of the nonlinear system.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-14T07:00:00Z
      DOI: 10.1142/S0219455425500798
       
  • Dynamic Analysis of the Bolted Joint Structure with Interval Uncertainties

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      Authors: Yong Liu, Jie Qu, Fangchao Yan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the dynamic influence of joint interfaces in bolted joint structures subjected to uncertain-but-bounded parameters. Firstly, applying the thin layer elements (TLE) represents the contact interfaces with nonuniform stiffness distribution. The stochastic model updating method is employed to identify the uncertain parameters of TLE. Secondly, the Legendre interval method (LIM) is applied to calculate the natural frequencies of bolted lap joints with uncertain parameters. By introducing the elastic modulus of TLE as interval vectors, relations between the natural frequencies and uncertain parameters could be analyzed using the LIM. Furthermore, the dependence of the dynamic response on TLE parameters can be established based on the modal superposition principle. Considering the influence of uncertain parameters, an uncertain acceleration frequency response surrogate function (UAFRSF) is proposed to predict the dynamic behavior and qualitatively analyze the parameter sensitivity of the bolted lap joints. The elastic modulus of TLE in different contact regions is selected as the interval variable. The acceleration frequency responses of the bolted lap joints under uncertain parameters are investigated. Compared with MCs simulations with 200 samples and Chebyshev interval method results, the effectiveness of the proposed method for solving the uncertain acceleration frequency response of bolted lap joints is verified. This research will provide theoretical support for improving the design of aero-engine joint structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-10T07:00:00Z
      DOI: 10.1142/S0219455425500877
       
  • Full-Scale Observations for the Combined Wind-Induced Responses of a
           Cylindrical Tower

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      Authors: Nakhorn Poovarodom, Nuttaphon Magteppong, Amorntep Jirasakjamroonsri
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents full-scale observations of wind-induced vibrations on a 140[math]m high cylindrical reinforced concrete tower under non-stationary and strong wind conditions. The vibration responses of the tower in two planar orthogonal axes and rotation, in conjunction with wind speed and direction data, have been utilized to extract the response characteristics. The primary focus is on discussing the correlation of wind-induced responses in three components: Along-wind, across-wind, and torsion. Throughout the varying levels of oscillation, the tower’s responses clearly exhibit correlations among these components. The correlation coefficients between along-wind and across-wind responses, as well as along-wind and torsional responses, remain negligible across the entire dataset. In contrast, during intense oscillations, there is a near-perfect correlation between the across-wind and torsional responses. Furthermore, the probability density functions (PDFs) of the response components under strong wind conditions significantly deviate from the Gaussian distribution and closely resemble the Cauchy distribution. The joint PDFs also indicate that the along-wind response is statistically independent of the other response components, while the across-wind response correlates well with the torsion, as indicated by the non-Gaussian distribution. This paper also includes distinct observations regarding dominant oscillating frequencies, torsional amplitudes, and vertical vibration amplitudes. The importance of this research lies in its examination of the relationship between different response components, a crucial aspect in understanding how structures behave under wind loading. By emphasizing the need for full-scale measurements, this study aims to provide valuable validation for previous theoretical and experimental research findings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-05-07T07:00:00Z
      DOI: 10.1142/S0219455425500786
       
  • Frequency Regulation in Nanocomposite Sandwich Joined Conical-Conical
           Shells with Open Cell Foam Partially Supported by Pasternak Elastic
           Foundation Using GDQ

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      Authors: Muwei Qiu, Huanqing Qiu, Zhaogui Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study investigated the natural vibration of a sandwich conical-conical shell that is partially supported by Winkler–Pasternak foundations. The sandwich system comprises an open-cell foam (OCF) core and laminated composite face sheets reinforced with graphene platelets using functionally graded models (FG-GPLRC). To account for through-the-thickness shear deformations and rotary inertias, the first-order theory of shells is combined with Donnell-type kinematic assumptions. Hamilton’s principle is utilized to establish the general motion equations and related boundary and continuity conditions. The resulting system of equations is discretized using the semi-analytical generalized differential quadrature (GDQ) approach. An eigenvalue problem is formulated to analyze the corresponding mode shapes and vibration frequencies for the shell ends and continuity criteria under various boundary conditions. Parametric experiments are conducted for sandwich conical-conical shells partially supported by Winkler–Pasternak foundations. This study examined the impact of multiple factors on the frequency of a joined shell structure, including the total thickness, FG-GPL face sheet thickness, various boundary conditions, the length of each cone segment, and the Winkler and shear elastic foundation. Notably, this research also analyzed the effects of a partial elastic foundation on the structure’s frequency for the first time.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-26T07:00:00Z
      DOI: 10.1142/S0219455425500762
       
  • Structural Damage Identification Based on Preprocessing Samples Mixed
           Training of Multi-Channel and Multi-Source Dynamic Response Data

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      Authors: Wei He, Rongyao Gong, Ningbo Wang, Yue Liu, Mingqi Peng, Haizhou Tan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Previous studies have shown that sampling processing and identification methods for neural networks damage identification in multi-channel and multi-source structural dynamic response data exhibit diversity, and the robustness and generalization issues of the model have not been effectively solved. This paper proposes a sample preprocessing technique and mixed training method suitable for multi-channel and multi-source dynamic response data to optimize the current structural damage identification methods based on neural networks. Through multi-dimensional discrete autocorrelation processing and Fourier transform, the preprocessed datasets from multiple sensors with multi-channel can access multi-channel CNN. Furthermore, the measured datasets from the actual structures are mixed with numerical simulation datasets before being used for neural network model training to address the model calibration and the imbalanced sample size under each classification label. The results of extensive model experiments and finite element verification of specimens show that the method performs outstandingly in detecting and identifying damage to simply supported beam structures using multi-channel CNN. The neural network model trained with preprocessed samples exhibits excellent robustness. The model using the mixed training method still performs well in identifying the accuracy of damage location and degree in simply supported beam structures after changing beam section and initial excitation. The method has certain generalization ability in detecting unknown damage in simply supported beam structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-25T07:00:00Z
      DOI: 10.1142/S0219455425500737
       
  • Study on Ill-Conditioned Total Least Squares Load Identification Method
           Based on the IGG Weight Function

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      Authors: Dakuan Xin, Jin Qian, Congshuai He, Hongxing Hua, Junchao Zhu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To address the ill-conditioned problem and unknown noise interference in ship load identification, this study proposes the ill-conditioned Total Least Squares (TLS) load identification method using the anti-error principle of the IGG weight function (IGG-TLS). First, the weight factor is iteratively updated through the IGG weight function. The weight matrix is constructed adaptively by multiplying the weight factor with the initial unit weight matrix. Then, the regularization criterion for the ill-conditioned IGG-TLS model is established based on the Tikhonov regularization principle. And the Lagrange multiplier is employed to solve the IGG-TLS method. Finally, the load identification accuracies of the IGG-TLS method are investigated through the simulation analysis and experimental verification of the rectangular plate under different noise and SNR conditions. The results demonstrate that the IGG-TLS method can achieve high accuracy in load identification without the need to pre-construct the weight matrix, even when the SNR is unknown. Additionally, the IGG-TLS method can effectively correct the identification errors in the TLS method, demonstrating high accuracy and noise immunity under conditions of equal-weight and unequal-weight noise.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-25T07:00:00Z
      DOI: 10.1142/S0219455425500804
       
  • A Sparsely-Measured Fitting Method for Identifying the Coefficients in the
           Governing Equation of a Beam

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      Authors: Yi He, Jie Yu, Judy P. Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes a method for identifying the coefficients in the governing equation of a beam from the sparsely measured response of bridge displacement. The following three steps constitute the procedure: First, the full-field displacement is reconstructed by the compressive sensing theory, which is innovatively applied in the spatial domain with a proposed general basis matrix. Then, the reconstructed displacement is fitted by the B-spline surface basis functions, and the derived control points are further adopted to compute the derivatives of displacement. The genetic algorithm is finally applied to seek the coefficients of the governing equation by substituting the fitted response into the equation. The proposed method is validated numerically and experimentally, including a parametric study to evaluate the performance subjected to various practical conditions. The salient advantages of the proposed method lie in that it requires few sensors for measurement, and the derivatives of displacement are computed robustly.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-24T07:00:00Z
      DOI: 10.1142/S0219455425400024
       
  • Influence of Prestress on Vibration Frequency of Beam String Structures
           Based on Exact Matrix Stiffness Method

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      Authors: Yu-Fei Guo, Wen-Hao Pan, Yao-Zhi Luo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Beam string structures (BSS) are frequently employed in large-span spatial structures due to their high load-carrying efficiency and elegant appearance. Owing to the neglect of the influence of prestress, the natural frequency of the BSS is often overestimated which could be crucial to the dynamic behavior of BSS. This paper presents an exact matrix stiffness analysis method (MSM) for investigating the relationship between prestress and the natural frequency of the planar BSS. A novel dynamic stiffness matrix of beam–columns considering the natural frequency and axial force is used to develop the MSM. The dynamic analysis of the structural vibration stability of BSS is performed by using the global structural stiffness matrix which is assembled from the element stiffness matrices in the global coordinate system. The proposed MSM with the exact dynamic element stiffness matrix for the dynamic analysis of the BSS is verified by comparing with previous results based on the finite element method. The illustrative examples demonstrate that the prestress in the cable has a negative effect on the natural frequency of the BSS and should be considered in the dynamic analysis. As the axial force increases from zero to the buckling load [math], the natural frequency of the BSS decreases from the maximum vibration frequency to zero. The influence of prestress on the vibration frequencies of BSS is particularly significant when the prestress to balance the loads is large, especially in the case of large dead and live loads (e.g. floor slabs).
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-24T07:00:00Z
      DOI: 10.1142/S0219455425500610
       
  • Vehicle–Bridge Coupling Vibration of Long-Span Concrete-Filled Steel
           Tubular Arch Bridge

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      Authors: Peng Yu, Cun Yu, Zhaoyong Ren, Longlin Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      An increase in the nonlinearity of the bridge will lead to a more obvious vehicle–bridge interaction effect and affect the vehicle response and driving comfort as the span increases. This paper establishes a refined finite element model of vehicle–bridge coupling for the 575 m long-span concrete-filled steel tubular arch bridge, Pingnan Third Bridge. Coupling vibration responses under different vehicle speeds, vehicle weights and road conditions of this bridge is analyzed. Then its comfort is assessed according to the comfort criterion. The results show that the vehicle–bridge coupling model has good agreement with the field test. The dynamic response of the bridge within the speed limit has no significant linear relationship with the magnitude of the vehicle speed without considering the pavement class. When the vehicle exceeds the speed limit, the dynamic response increases sharply with the increase in speed. The increase in vehicle weight leads to an increase in the maximum dynamic deflection of the bridge and a decrease in the impact coefficient, but the actual total response of the bridge does not decrease. The worse the road surface condition, the more dramatic the dynamic response of the bridge structure, taking into account the road surface level.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-24T07:00:00Z
      DOI: 10.1142/S0219455425500646
       
  • A Nonlocal Numerical Solution Based on Carrera Unified Formulation for
           Static and Free Vibration Analysis of Laminated Composite Nanoplate

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      Authors: Thanh Cuong-Le, Minh Hoang Le, Thi Thuy Linh-Nguyen, Van Hai Luong, Samir Khatir, Minh Thi Tran, Thai-Binh Nguyen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents an advanced numerical model based on Carrera unified formulation (CUF) and isogeometric analysis (IGA), the size-dependent finite element unified formulation model is proposed to investigate the static bending and free vibration of laminated composite nano-plate. The CUF type of trigonometric function with nine degrees of freedom is used to simulate the displacement fields of laminated nano-plate. The size effect of nano-plate structures is included through the Eringen’s nonlocal elastic theory. The size-dependent governing equations for static bending and free vibration of laminated are established based on CUF, IGA and nonlocal theory. The correctness of the presented numerical model is verified by comparison with existing solutions. Furthermore, with the addition of a nonlocal effect, the plate’s stiffness decreases correlating to an increase in nonlocal parameter. Through different calculations, the changes in the static and free vibration responses of laminated composite nano-plate are effected by nonlocal parameter, plate length-to-thickness ratio, and boundary conditions including Young’s modulus ratio.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-22T07:00:00Z
      DOI: 10.1142/S0219455425500609
       
  • Gas-Spring Quasi-Zero Stiffness Air Damping Isolator for Vertical
           Vibration Control of Indoor Substation Excited by Metro Loads

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      Authors: Kunjie Rong, Zhengquan Cheng, Li Tian, Yu Zhang, Yong Liu, Siyuan Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To mitigate the metro-induced vertical vibration of the indoor substation structure, this study proposes a gas-spring quasi-zero stiffness air damping isolator (AD-QZSI) with excellent low dynamic stiffness and high-static stiffness characteristics. The working principle and mechanical properties of the AD-QZSI are introduced and studied through theoretical and numerical methods. A model for substation considering soil–structure–equipment interaction is established using the software ABAQUS, its accuracy is validated based on a series of measured data from actual projects, and the AD-QZSI’s simulation method and parameter design method are described in detail. The air damper’s stiffness [math] is integrated into the isolator’s mechanical model, theoretically and numerically achieving an accurate simulation of AD-QZSI’s nonlinear mechanical properties. The numerical results have an error of less than 5% with the measured data, indicating that the model is able to better capture the actual structure’s dynamic characteristics and is reasonable to be employed for subsequent analysis. Numerical results show that AD-QZSI can significantly reduce the structural vertical vibration, and its control effect is better in the whole frequency band, in particular, the effect is also visible in the low-frequency band, indicating that its vibration isolation frequency band is wider than that of traditional QZS isolator. With the vibration source distance increasing, the control effect of AD-QZSI presents a tendency to decrease and then level off, and its vibration isolation gain is weakened by the continuous increase of the damping ratio greater than 0.01. Moreover, the equipment’s dynamic amplification factor of the isolated structure decreases significantly. Finally, the proposed AD-QZSI can obtain ideal quasi-zero stiffness characteristics by adjusting the air pressure, and the adopted air damper belongs to the green low-carbon components, featuring great practical value and application prospects.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-22T07:00:00Z
      DOI: 10.1142/S0219455425500683
       
  • Optimal Design and Performance Evaluation of HMDV Inertial Suspension
           Based on Generalized Skyhook Control

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      Authors: Xiaofeng Yang, Shaocong Zeng, Changning Liu, Xiaofu Liu, Zhipeng Wang, Yi Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The hub motor driven vehicle (HMDV), due to the increase in unsprung mass and the influence of uneven electromagnetic radial forces from road excitations, results in the deterioration of body acceleration, significantly impacting ride comfort. This seriously impacts ride comfort. However, the inerter proves effective in reducing low-frequency vibrations in body acceleration, and skyhook control significantly enhances ride comfort. To fully exploit the benefits of the inerter, comprehensively elevate skyhook control performance, and effectively counteract the worsening of body acceleration caused by the hub motor, this study integrates skyhook control with an inertial suspension system. This integration markedly improves the suspension’s low-frequency isolation performance, thereby substantially enhancing vehicle ride comfort. Firstly, establish a quarter-vehicle dynamics suspension model based on the Switched Reluctance Motor (SRM) driven wheel motor system. Subsequently, confirm the constraints of two different generalized skyhook inertial suspension structures separately and optimize their parameters to determine the most suitable parameters for each structure. Finally, analyze the impact of these two suspension types on body acceleration to derive the optimal structure. Simulation results demonstrate that, compared to traditional suspensions, the optimized generalized skyhook inertial suspensions reduce the Root Mean Square (RMS) values of body acceleration and suspension working space by 18.8% and 22%, respectively. This reduction is particularly significant in the 0[math]2[math]Hz frequency range, effectively enhancing ride comfort. It also adequately validates the effective utilization of the advantages of inertial suspensions and skyhook control.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-22T07:00:00Z
      DOI: 10.1142/S0219455425500695
       
  • A Novel Mayfly Algorithm with Response Surface for Static Damage
           Identification Based on Multiple Indicators

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      Authors: Zhifeng Wu, Yanpeng Song, Hui Chen, Bin Huang, Jian Fan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper proposes a novel structural damage identification approach coupling the Mayfly algorithm (MA) with static displacement-based response surface (RS). Firstly, a hybrid optimal objective function is established that simultaneously considers the sensitivity-based residual errors of static damage identification equation and the static displacement residual. In the objective function, the static damage identification equation is addressed by the Tikhonov regularization technique. The MA is subsequently employed to conduct an optimal search and pinpoint the location and intensity of damages at the structural element level. To handle the inconformity of the static loading points and the measurement points of displacements, the model reduction and displacement extension techniques are implemented to reconstruct the static damage identification equation. Meanwhile, the static displacement-based RS is constructed to calculate the displacement residual in the hybrid objective function, thereby circumventing the time-consuming finite element calculations and improving computational efficiency. The identification results of the numerical box girder bridge demonstrate that the proposed method outperforms the particle swarm optimization, differential evolution, Jaya and whale optimization algorithms about both convergence rate in optimal searching and identification accuracy. The proposed method enables more accurate damage identification compared to methods solely based on the indicator of the residual of static damage identification equations or displacement residual. The results of identifying damage in the 21 element-truss structure and the static experiments on identifying damage in an aluminum alloy cantilever beam confirm the high efficiency of the proposed approach.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-22T07:00:00Z
      DOI: 10.1142/S0219455425500713
       
  • Simultaneous Identification of Vehicle Load and Structural Damage on
           Renyihe Bridge

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      Authors: Guo-Mu Ji, Xiao-Chen Liu, Yuan Yuan, Ya-Xin Guo, Jin-Qiao Chen, Hao-Ran Hu, Wei-Jie Yang, Guang-Dong Liu, Xiao Fan, Xiao-Xiang Cheng, Shi-Tong Hou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Simultaneous identification of vehicle load and structural damage is an issue of practical significance in structural health monitoring and maintenance of in-service concrete bridges. However, most methods proposed in history to deal with this engineering issue are solely based on data from a single source of structural vibration response measurement, which are subjected to problems such as incomplete understanding of the structural health, the computational inefficiency and the easy failure of the monitoring system. To this end, this paper proposes a new method of synthesizing data generated from two different types of sensors (the strain gauges and the accelerometers) to simultaneously identify the vehicle load and the structural damage which is established on the theories of weigh-in-motion method based on the strain influence line. The new method, which is supposed to be able to well solve the problems with the traditional approaches disseminated to the profession, is formulated in a flowchart for use, and applied to the actual Renyihe Bridge (a concrete rigid-frame continuous highway bridge with spans of [math]) to validate its effectiveness. The results suggest that the new method is of high accuracy in use in low vehicle speed scenarios and superior to the traditional simultaneous identification approach based on unitary structural acceleration sensing.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-22T07:00:00Z
      DOI: 10.1142/S0219455425500750
       
  • Modeling and Analysis of 1:3 Internal Resonance of Suspension Bridge Under
           Boundary Excitations

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      Authors: Peng Cheng, Houjun Kang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study investigated the nonlinear dynamic behavior of suspension bridge subjected to multi-frequency boundary excitations. Firstly, the nonlinear dynamic model of the suspension bridge subjected to multi-frequency boundary excitations is established. The in-plane vibration equations are derived based on Hamilton’s principle, taking into account the effects of geometric nonlinearity of the girder-deck and main cable as well as the stiffness of hangers. Secondly, the Galerkin method is used to solve for the frequencies and corresponding mode shape functions. Thirdly, the corresponding modulation equations are obtained based on the multiple scales method, and the 3:1 internal resonance between two symmetrical modes is analyzed. Combined with numerical analysis, the nonlinear dynamic behavior between modes of the suspension bridge is demonstrated through the frequency–response, force–response, and time history curves. The results indicate that the drift phenomenon appears when perturbing the amplitude and frequency of the different excitations, and the system exhibits intricate dynamic responses.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500051
       
  • Damage Identification of Simple Supported Bridges Under Moving Loads Based
           on Variational Mode Decomposition and Deep Learning

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      Authors: Chao Wang, Xiang Pan, Tian-Yu Qi, Gui-Ning Han, Wei-Xin Ren
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Aiming at rapid and economical damage detection of a large number of simple supported bridges, a new structural damage identification method under moving load based on variational mode decomposition (VMD) and deep learning is proposed. Firstly, a moving vehicle is used as an exciting load to invoke structural damage feature and enhance the signal-to-noise ratio, and the structural vertical acceleration response is extracted by a finite element simulating analysis under various damage cases. In order to simulate the influence of noise and expand the samples, Gaussian white noise is added to the extracted data, and then the response signal is decomposed into a series of intrinsic mode functions (IMFs) using VMD, and the optimal IMF component is selected as the damage sample of the structure. Then, a one-dimensional convolutional neural network (CNN) model is built and trained by the various samples of damage. The vibration response of the practical bridge is processed and inputted by the trained CNN model to identify the location of the damage and degree of the structure. Finally, the effectiveness and anti-noise performance of the proposed method are verified through numerical analysis and a simply supported beam bridge model experiment. The results show that the average identification accuracy of the numerical simulations and experimental is 93.4% and 86.8% with 20% Gaussian white noise, respectively. Sensors at different locations have almost the same identification effect for various cases of damage, so it is possible to identify structural damage only using a small amount of accelerometer.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500658
       
  • Vibrational Analysis of Axially Loaded Rayleigh Beams on Variable Winkler
           Foundations with Implications for Structural Design

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      Authors: Abdulmohsen Alruwaili, Javeria Zafar, Rab Nawaz, Hani Alahmadi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, we explore the complex vibration problem of a Rayleigh beam under axial loads, positioned over a variable Winkler foundation with elastic properties changing along its length. The investigation delves into how factors like rotational inertia, axial forces, and foundation properties affect the beam’s dimensionless eigenvalues and eigenmodes. Employing the Differential Transform Method (DTM), we tackle the governing equations across various foundation conditions, including constant, linear, and parabolic variations. The results align well with the previous research, affirming their precision between scenarios considering or neglecting the elastic foundation’s effects. Notably, we emphasize the influence of linear spring stiffness on vibration characteristics, overshadowing rotary spring stiffness. Thus, the important novelty of the study lies in its comprehensive investigation into the vibration dynamics of a Rayleigh beam under axial loads on a variable Winkler foundation with elastic properties varying along its length. The findings illuminate a previously unexplored dynamic: the intricate interplay between linear and rotary spring stiffness, showcasing the dominant impact of linear stiffness on vibration characteristics. Of significant note is the profound effect of axial forces on fundamental eigenvalues, underscoring their critical role in structural behavior. These developments possess substantial practical implications, providing invaluable guidance for the accurate modeling of beams supported by elastic foundation, thereby enhancing structural design and performance.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500671
       
  • Investigation on the Dynamic Performance of High-Speed Trains Under Tunnel
           and Crosswind Environments Considering Car-Body Flexibility Based on a
           CFD-MBD Co-Simulation Method

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      Authors: Yanlin Hu, Chao Chang, Qinghua Chen, Xin Ge, Liang Ling, Kaiyun Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The dynamic performance of railway vehicles is significantly impacted by sudden-changed aerodynamic loads. To investigate the dynamic performance of high-speed trains (HSTs) under tunnel and crosswind environments considering the car-body flexibility, an intensive study is conducted. First, a train–track interaction dynamic model with a flexible car body is established in SIMPACK for dynamic response analysis. Concurrently, an aerodynamic model for calculating the distribution of aerodynamic loads is found in FLUENT to determine forces and moments applied to each part of the car body. Then, the two models are coupled utilizing a co-simulation method developed based on the User Data Protocol (UDP). Finally, a case study is carried out, involving a train passing through tunnels subjected to crosswinds. The results reveal that the distribution of aerodynamic loads on the car-body affected by crosswind is time-variant and non-even. Interestingly, the dynamic simulation results are almost unaffected by the method used to allocate the loads on the car body. Variations in the aerodynamic loads affected by crosswinds lead to flexible first-order diamond mode vibration of the car body at around 8.5[math]Hz when exiting the tunnel. As the crosswind speed continues to increase, vibrations at frequencies of 18.2[math]Hz and 24.2[math]Hz will be enhanced, corresponding to the bending mode and combined mode of the car body. However, similar flexible vibrations are insignificant when the vehicle enters the tunnel. In addition, the vertical wheel–rail interaction obtained by the dynamic model with a rigid car body is slightly greater than that with a flexible car body.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500701
       
  • Targeted Energy Transfer Evaluation for Nonlinear Vibrations of Elastic
           Medium-Finite Length Beam System Using Nonlinear Energy Sink Theory

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      Authors: Jianjun Ma, Zongtong Liu, Chaosheng Wang, Songyang Wang, Da Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The elastic medium can usually reduce the vibration of supporting structure, and the impact of the interaction on the vibration characteristics of the structure is similar to the characteristic of nonlinear energy sink. At present, the dynamic research of beam on elastic foundation considering soil motion has been paid more and more attention. According to the modified Winkler model, the finite-depth elastic medium can be considered to the nonlinear energy sink mass, and the vibration energy dissipation capacity and parameter optimization of the elastic medium supporting finite-length beam under half sine pulse are studied. The Galerkin truncation is applied to the discretization of the governing equations. The numerical solution of the beam coupling system with simple support on the elastic medium is obtained by applying the fourth-order Runge–Kutta method. Based on this, the input energy ratio of the elastic medium dissipation is investigated. Furthermore, through the analysis and optimization of targeted energy transfer and dissipation, the dissipation effect of the finite range elastic medium on the vibration energy of its supporting beam is revealed, and the optimal parameter range of the elastic medium is proved. The results show that after adjusting the elastic medium parameters by technical means, the nonlinear energy sink can absorb most of the vibration energy of the beam quickly and effectively, and the optimal energy dissipation ratio can reach 95.16[math]. The quantitative evaluation of the energy dissipation in elastic medium within soil–structure interaction effect is realized.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500725
       
  • Fragility Analysis of a Transmission Tower-Line System Subjected to Wind
           and Ice Loads Considering Fatigue Damage

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      Authors: Jia-Xiang Li, Yu-Shun Zuo, Ling-Peng Wang, Zhi-Qian Dong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Disasters such as ice and wind can pose a serious threat to the normal operation of power transmission lines. Wind-induced fatigue damage can further reduce the load-carrying capacity of transmission towers, increasing their fragility to ice and wind disasters. To assess the comprehensive capability of transmission towers to resist extreme ice and wind disasters, this paper proposes a failure probability evaluation framework for transmission towers considering wind-induced fatigue damage under the coupled effect of ice and wind. Taking a certain transmission line in Hunan as an example, the failure probability caused by ice and wind disasters is calculated for different years of service. First, based on the historical meteorological data in three cities in Hunan, a joint probability model of wind speed and wind direction considering their correlation is established using the copula function. Then, based on this probability model, the wind-induced fatigue damage of transmission towers is calculated using the Miner linear damage theory and the S-N curve. Subsequently, the fragility of the tower under the coupled load of ice and wind is calculated for different years of service. Finally, by combining the structural fragility function with the joint probability distribution model of ice thickness and wind speed, the collapse probability of the transmission tower under the action of ice and wind disasters is calculated. The results indicate that the influence of wind-induced fatigue damage cannot be ignored when transmission towers encounter ice and wind disasters. With increasing service time, the ability of transmission towers to resist ice and wind disasters gradually decreases, and the failure probability also increases under extreme ice and wind conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425500749
       
  • Constructing Pavement Roughness of a Three-Dimensional Bridge in Abaqus
           for Vehicle Scanning Method

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      Authors: Judy P. Yang, Han-Cyuan Jiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a procedure for constructing pavement roughness in a three-dimensional bridge subjected to a vehicle using Abaqus is proposed for numerical simulation of vehicle–bridge interaction problems. As the plug-in RufGen, a graphical user interface in Abaqus/CAE for surface interaction, creates a hexahedron with a rough surface and attaches it to the bridge deck, the resulting weight of a bridge model can be much larger than the original one. In the vehicle scanning method, it is essential to keep a finite element bridge model with an unchanged weight after imposing a rough surface on it in consideration of the roughness effect for bridge health monitoring. As such, the proposed procedure is aimed at resolving this issue, with the following two highlights: First, the Toeplitz matrix is introduced to generate a rough surface in three dimensions to ensure the randomness of roughness in the two perpendicular directions under a given roughness profile. Second, a shell-type rough pavement is established for directly using as the bridge pavement or attaching to the bridge deck, which minimizes weight increment in the bridge.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-13T07:00:00Z
      DOI: 10.1142/S0219455425710014
       
  • Selection of the Span Length of an Analogic Finite Beam to Simulate the
           Infinite Beam Resting on Viscoelastic Foundation Under a Harmonic Moving
           Load

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      Authors: Y. B. Yang, S. Y. Gao, K. Shi, X. Q. Mo, P. Yuan, H. Y. Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Continuous rails are often modeled as infinite beams. In this paper, closed-form solution is newly derived by the residue theorem and Green’s function for the dynamic response of an infinite beam resting on viscoelastic foundation under a harmonic moving load. The most suitable span length will be determined for the analogic finite beam (which can be more conveniently used in practice) to best represent the deflection of the infinite beam for practical reasons. Starting from the equations of motion, closed-form solution is firstly derived for the infinite beam. Then, it is verified by the finite element method (FEM) using semi-infinite elements to simulate the infinite boundary conditions. The deflection curves of the infinite beam and analogic finite beam are compared for various parameters. It is concluded that: (1) a larger span length should be adopted for the finite beam under higher load speeds or with foundations of softer stiffness or larger damping; typically, for load speeds [math][math]m/s (324[math]km/h); (2) typically, a span length of 50 m can be adopted for the analogic beam for UIC rails resting on foundations with stiffness [math] and damping coefficient [math]; (3) the peak deflection of the infinite and analogic finite beams occurs after the moving load for foundations with larger damping; and (4) the shape and amplitude of the deflection curve vary as the load frequency and amplitude varies, but the difference between the two beams is insignificant for moving loads with high frequencies.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S0219455425400012
       
  • The Influence of CRTS II Slab Ballastless Track Upper Arch Deformation on
           the Wheel Jumping Law of High-Speed Vehicle

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      Authors: Kai Gong, Cheng Wang, Jun Xiang, Wenjie Guo, Jiangling Luo, Wenjun Bian
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To study the impact of upwarp deformation in the ballastless track on the jumping behavior of the high-speed vehicle, utilizing UM and ANSYS joint simulation, a vertical vibration model of high-speed vehicle on CRTS II slab ballastless track was developed based on the non-Hertz wheel–rail contact model of virtual penetration theory. By using the single-wave cosine curve simulating the characteristics of upwarp deformation in the track slab, we calculated the whole process of wheel jumping. This allowed us to analyze how the amplitude and wavelength of the track slab upward deformation influence the vibration response of the vehicle–track system. Our findings indicate that when a wheel passes through the arch section of the track slab, the entire wheel jumping process consists of distinct stages: “wheel–rail bonding, wheel–rail separation, wheel–rail impact (one or more times), and wheel–rail bonding.” As the amplitude of upwarp deformation increases and the wavelength decreases, significant changes occur in several parameters, including the vertical force between the wheel and rail, wheel unloading rate, wheel jump height, frequency, duration, and vertical displacement of the rail. Additionally, when the wavelength is between 2 and 6[math]m and the amplitude is 8[math]mm, the vertical force between the wheel and rail becomes zero, the wheel load reduction rate is one, and the wheel jumps. When the wavelength is less than 3[math]m, the wheel jump height exceeds the flange height, increasing the risk of derailment. Meanwhile, during the first wheel–rail impact, the wheel–rail vertical force and the rail vertical displacement reach their maximum, potentially impacting rail service performance negatively. Finally, compared to the amplitude of the track slab camber deformation, its wavelength has a greater impact on the entire process of wheel jumping. It is recommended that attention be paid to the change in the wavelength of the track slab camber during the maintenance and repair of the ballastless track.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S0219455425500270
       
  • Vibration, Buckling and Stability Analyses of Spinning Bi-Directional
           Functionally Graded Conical Shells

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      Authors: Xiaochao Chen, Qing Gao, Songbing Huang, Kangni Chen, Yiwan Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the free vibration, buckling and dynamic stability of spinning bi-directional functional gradient materials (BDFGMs) conical shells. The material properties vary along the thickness and axial direction. The dynamics model is established based on the first-order shear deformation theory and the governing equations and boundary conditions of the conical shell are derived employing Hamilton’s principle. Subsequently, the differential quadrature (DQ) method is employed to discretize the governing equations into an algebraic system of equations for solving and analyzing the free vibration characteristics of the conical shell. The theoretical model’s accuracy and the solution method’s reliability are rigorously verified. The effects of temperature, functional gradient index, and rotation on the vibration characteristics, traveling wave vibration and critical speed of the conical shell in a thermal environment are systematically explored through numerical analysis. The results indicate that both the material gradient index and temperature increase lead to a decrease in the shell’s natural frequency. For the spinning BDFGMs shell, elevated temperature causes the occurrence of trailing wave vibration to advance to the critical speed. Centrifugal force emerges as the primary factor influencing the critical buckling load and unstable region variation of the spinning shell.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S0219455425500312
       
  • Free Vibration of Axially Loaded Functionally Graded Porous Cracked Beams

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      Authors: Yousef S. Al Rjoub, Mohammad A. Al-Momani
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study employed a method of analysis to examine the free oscillation behavior of functionally graded (FG) porous-cracked beams under axial loads and varied boundary conditions. The cracked beam system was composed of interconnecting beam segments kept together by massless rotating springs. Based on the Timoshenko beam theory (TBT) or Euler–Bernoulli theories (EBT), each segment was sectionally flexible. Using a power-law function, mechanical features were expected to gradually change along with the height of the beam. Two different pore distributions, even and uneven, were also explored. Subsequently, Hamilton’s theory was used to derive the equations of kinematic motion for FG-cracked porous beams, and the transfer matrix (TMM) approach was used to get the determinantal equation. A parametric analysis was performed to evaluate how cracks, porosity distribution, slenderness ratio, volume fraction index, boundary conditions, and axial load affect the dynamic characteristics of FG beams. The results revealed that the suggested analytical approach provided several findings that were similar to the existing analytical outcomes in the literature. Moreover, the computer analysis demonstrated that porosity, especially when there were cracks, significantly affected the eigenfrequencies of FG beams. Hence, this study opened the door for possible applications in a variety of engineering settings by offering some crucial insights into the complex dynamics of FG porous-cracked beams.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S0219455425500580
       
  • Dynamic Analysis and Optimization on Passive/Active Vibration Reduction of
           a Beam Structure with Distributed Smart Foams

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      Authors: Wen-Yong Zhang, Mu-Qing Niu, Lan-Feng Deng, Yimin Fan, Li-Qun Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A smart foam is a vibration absorption structure integrated with piezoelectric material and shows promise for a highly efficient structural vibration reduction both passively and actively. The arrangement of the smart foams on the primary structure is a key issue in practical engineering. In this work, the vibration reduction performances of distributed smart foams attached to a simply supported beam are investigated, and the distribution scheme is optimized. The dynamic equations of the vibration system are established for passive and active vibration reduction, respectively. The frequency responses are analyzed based on a Newmark-[math] method, and the accuracy is verified by a finite element analysis. An optimization method based on the genetic algorithm is proposed for the smart foams’ quantity and locations. The study reveals that, with the same total attached mass (1% of the beam mass), a limited distribution of smart foams achieves a larger vibration reduction ratio than a single smart foam or uniformly distributed smart foams. For the passive reduction mode, the optimal scheme is to arrange four smart foams at the middle of the beam, and a reduction ratio of 38% is achieved. It is related to both the first-order modal shape of the beam and the mass distribution of smart foams. For the active reduction mode, the optimal scheme is to arrange two smart foams separately, and 98% of the vibration is reduced. The optimal location is no longer at the middle of the beam, because the active moment of the piezoelectric beam makes the main contribution, rather than the passive vibration absorption. This research provides an optimization method and instructions for both passive and active vibration reductions of smart foams.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S0219455425500634
       
  • A New Approach to Structural Damage Identification Based on Power Spectral
           Density and Convolutional Neural Network

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      Authors: Youliang Fang, Chanpeng Li, Sixiang Wu, Menghao Yan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In the field of structural health monitoring, vibration-based damage identification remains a formidable challenge. Key to this challenge is the establishment of a reliable association between observed vibration characteristics and the actual state of structural damage (e.g. stiffness reduction). This association not only accurately indicates the presence of damage, but also the location and severity of the damage. To solve this complex pattern identification problem, a large number of approaches, including deep learning, have emerged in recent years. In this paper, we propose a new structural damage identification method that utilizes the vibration information of the structure and a convolutional neural network based on Alex NET improvement. The method consists of calculating the acceleration response power spectral density of damaged and undamaged structures under impact loading separately, and then making a difference between the two power spectral data, and subsequently introducing these power spectral difference data into the convolutional neural network for training. The use of power spectral density analysis as a preprocessing step converts the time-domain signals into frequency-domain signals, and this conversion allows the convolutional neural network to capture and learn from the specific frequency characteristics of the data, thus facilitating the learning process of the neural network model. In this paper, the effectiveness of the method is critically evaluated through numerical simulation and experimental validation, and 3% and 5% noise are added to the numerical study to test the robustness of the method. During the convolution neural network training process, the optimal training mean squared error (MSE) is [math] in the case of no noise addition; the optimal training MSE is [math] in the case of noise addition. Both the results of simulations and experiments confirm the high accuracy and good robustness of the method in localizing structural damage.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-08T07:00:00Z
      DOI: 10.1142/S021945542550066X
       
  • Stochastic Vibration-Driven Fatigue Analysis for Steel Structure Bridges
           Considering Track Irregularity

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      Authors: Yahao Li, Nan Zhang, Qikan Sun, Chaoxun Cai, Kebing Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes a method for assessing the effect of stochastic vibrations resulting from track irregularities which are rarely studied but significant on bridge fatigue. First, the pseudo-excitation method is utilized to determine the power spectrum density of stress. Subsequently, the trigonometric series method is employed to acquire the stress time history set. Then, a traditional fatigue life calculation method is employed for analysis. By utilizing a post-sampling method, the need for costly repetitive solutions of the vehicle-bridge coupling system is eliminated. Numerical simulations are conducted on a steel truss bridge, revealing the non-negligible effect of track irregularity on bridge fatigue performance. The study investigates the underlying mechanism, highlighting the pronounced influence of long-wave track irregularity. Moreover, the research explores the correlation between track smoothness and bridge fatigue performance, demonstrating that a decrease in track smoothness leads to an increase in fatigue loss. These findings emphasize the necessity of considering stochastic vibrations when evaluating bridge fatigue, providing valuable insights for bridge design and maintenance.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-05T07:00:00Z
      DOI: 10.1142/S0219455424502596
       
  • Symmetric/Asymmetric Vibrational Characteristics of Bi-Directional
           Functionally Graded Annular Microplates

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      Authors: Longbo Liu, Fangqing Gao, Bo Zhang, Juan Liu, Yukang Yang, Hexuan Deng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a free vibration model of bi-directional functionally graded (BD-FG) annular microplates is established based on the modified couple stress theory (MCST) and the first-order shear deformation theory (FSDT), and the corresponding governing equations are derived from Hamilton’s principle. The annular microplates are assumed to be composed of metal and ceramic materials, and the equivalent material properties are a combination of power-law function and exponential ones. The generalized differential quadrature method (GDQM) is used to obtain the vibration frequencies and mode displacements for the C–C, S–C, C–S, and S–S (S: simply supported; C: clamped) annular microplates. The convergence and validity of the proposed model are verified through selective numerical examples. Further, the effects of gradient index, material length scale parameter, boundary conditions, and geometrical dimensions on the symmetric/asymmetric vibration frequencies of the annular microplate are explored. The modal assurance criterion is applied to estimate the influence of the radial gradient index and material length scale parameter on different-order mode displacements of the annular microplate. The results show that: (1) the vibration frequencies of the annular microplate are sensitive to changes in the geometry and boundary conditions; (2) compared with the axial gradient index, the radial gradient index not only affects the vibration frequencies of the annular microplate, but also impacts the distribution of the highest and lowest points of the vibration mode displacements as well as the vibration mode nodal lines; (3) as the material length scale parameter increases, the vibration frequencies are significantly increased, and the higher-order vibration modes of the annular microplate also change.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-05T07:00:00Z
      DOI: 10.1142/S0219455425500592
       
  • A Multiple Scale Approach to Nonlinear Vibrations and Stability of Doubly
           Curved Shells/Panels Under External and Parametric Excitations

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      Authors: Mohammad Amin Montaseri, Mohammad Rahmanian, Seyyed Ali Asghar Hosseini
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study focuses on nonlinear vibrations and stability of doubly curved shells/panels. The thin-walled shell structure is assumed to be acted upon by external loads as well as parametric excitation. Using the first-order shear deformation Fülgge theory assumptions, governing equations of motion are derived for a general doubly curved geometry. Nonlinear components which are compatible with the Von-Karman kinematic assumptions are retained in the formulation and the rest of nonlinear components are neglected due to the fact that strains are assumed to be small and rotations to be moderate. The formulation can be readily reduced to any geometry including cylindrical shells and spherical panels, as benchmark examples in this study. Employing the Galerkin discretization approach and applying a modification to the Volmir assumption, a reduced order form of the original system is determined, which is shown to be a great representative of the original system with much more computational advantages. Using the method of multiple scales, the reduced order nonlinear governing equations are solved to discover the primary resonance, forced vibration characteristics and stability margins of thin-walled shells/panels under the action of parametric excitation. Several interesting findings on nonlinear behavior of cylindrical shells and spherical panels (as benchmark geometries) are presented while giving a demonstration of the accuracy and computational advantages of the proposed model.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-04T07:00:00Z
      DOI: 10.1142/S0219455425500543
       
  • Vehicle Response-Based Bridge Modal Identification Using Different
           Time–Frequency Analysis Methods

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      Authors: Xuan Kong, Quanyu Tang, Kui Luo, Jiexuan Hu, Jinzhao Li, C. S. Cai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Modal identification of bridges based on the responses of moving vehicles, termed as the indirect method, has drawn much attention in recent years. This indirect method has been proven to be capable of identifying bridge frequencies and mode shapes in the feasibility research. However, in the presence of additional factors such as vehicle speed and road surface roughness, it is difficult to identify high-order frequencies and high-resolution mode shapes of the bridge. The authors previously proposed a tractor-double-trailers model and the time–domain subtraction method to obtain the relative displacement of two trailers for bridge modal identification. In this study, the authors develop a methodology to improve the identification performance by combining the EMD technique and the time–frequency analysis method. The EMD technique is applied to separate the multi-source response signals of the trailers to obtain the signal component that contains only the bridge vibration. Then, different time–frequency analysis methods such as the short-time Fourier transform (STFT), Wigner–Ville distribution (WVD), and continuous wavelet transform (CWT) are adopted to construct the high-resolution bridge mode shapes. Numerical studies with one-dimensional and three-dimensional bridge models are conducted to verify the proposed method and investigate the effects of different factors. Finally, a laboratory test is implemented on a scaled bridge to verify the performance of the proposed method. The results show that the proposed method is able to separate the vehicle frequency and bridge frequencies, which facilitates the identification of bridge frequencies from the dynamic response of moving vehicles. Meanwhile, the CWT method performs the best in the identification of modal shapes among the three time–frequency analysis methods.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-04T07:00:00Z
      DOI: 10.1142/S0219455425500622
       
  • A Novel High-Order Sandwich Plate Theory-Based Isogeometric Analysis for
           Free Vibration of Variable Angle Tow Composite Sandwich Plates with
           Complex-Shaped Cutouts

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      Authors: Xiaodong Chen, Fengjian Zhang, Guojun Nie
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Advanced automated fiber placement technologies enable variable angle tow sandwich structures possible, which provides an extended flexibility in stiffness tailoring to design lightweight sandwich structures with superior performance. However, complex-shaped openings within this new type of sandwich structures bring great challenges when dealing with vibration problems. In this paper, an isogeometric analysis (IGA) formulation based on a novel high-order sandwich plate theory is developed for the first time to the study of free vibration of variable stiffness sandwich plates with complex-shaped cutouts. The proposed new high-order sandwich plate model is formulated based on the idea of layerwise modeling, that is, the first-order shear deformation theory is employed to characterize the kinematics of the two skins, while the high-order theory based on hierarchic Legendre polynomials is applied to describe the kinematics of the core. The weak-form governing equations for free vibration problems of the perforated sandwich plates are first derived from the virtual work principle, and then the IGA formulation based on the non-uniform rational B-splines (NURBS) is applied to obtain the eigenfrequencies and the corresponding eigenmodes. The novelty of this work lies in that the introduction of hierarchic Legendre polynomials enables the kinematics of the core to be enriched to any desired expansion order, which shows great superiority over its traditional counterpart such as extended high-order sandwich panel theory (EHSAPT). On the other hand, the developed IGA procedure based on the novel high-order sandwich plate theory is applicable to a general sandwich plate even with complex-shaped cutouts. The accuracy and effectiveness of the developed IGA procedure are validated by comparing against the results available in the literature and those obtained using ABAQUS. Effects of cutout size, boundary condition and fiber angle on the vibration characteristics of the perforated sandwich plates are discussed in numerical examples. The results presented herein may be beneficial for the design of variable stiffness sandwich plates with complex-shaped cutouts.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-04-01T07:00:00Z
      DOI: 10.1142/S0219455425500579
       
  • Dynamic Modeling and Optimization Analysis of Rigid–Flexible Coupling
           Manipulator Based on Assumed Mode Method

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      Authors: Weiwei Sun, Kun Dai, Yue Liu, Fei Ma, Zhongyuan Guo, Zhouxiang Jiang, Shuangfu Suo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Lightweight robotic arms are one of the main technologies to improve the working performance of robotic arms in the future. Focusing on the spatial vibrations issue brought about by the light-weighting of a space robotic arm in this paper, a rigid–flexible coupling dynamics model of a space robotic arm system was established based on the assumed mode method and Lagrange method. Based on the lightweight flexible robotic arm structure, a comparative analysis of the first four mode functions was conducted under different fixed constraints and physical properties to determine the mode order that matches the simulation analysis of this robotic arm, thus, further simplifying the rigid–flexible coupling dynamics equations of the system. The overall rigid model and simplified dynamic model of the robotic arm system were solved by using MATLAB, resulting in a motion trajectory of the flexible arm end in space. The three-dimensional model was validated and simulated using virtual prototype technology under the same joint inputs as the model in MATLAB. The simulation results demonstrated that the trajectory of the end of the flexible arm was basically the same between simplified dynamics model simulation and virtual prototype simulation, and the maximum deviation of the end trajectories of the flexible connecting rods [math] and [math] was less than 18[math]mm and 58[math]mm, respectively. Meanwhile, the trajectory trend of the end of the flexible arm in the two aforementioned models was the same as the simulation results of the ideal model (overall rigid model). The above conclusions can verify the correctness of the mathematical model of dynamics obtained from the calculations in this paper. In addition, the research data showed that the maximum vibration deviation of the flexible arm was stabilized within a certain value range under different joint inputs, and this research also provided theoretical support for the late vibration suppression control of the spatial rigid–flexible coupled robotic arm.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500476
       
  • The Stability of Corroded Circular Steel Tubes Under Axial Compression
           Investigated Through Testing, Finite Element Analysis and Theoretical
           Approaches

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      Authors: Lisheng Luo, Pan Su, Yongqiang Zhang, Chunlei Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Circular steel-tube members are extensively used in various large-scale steel structures. The detrimental effects of corrosion on the ultimate bearing capacities of these structures require urgent attention. This study designed six circular steel tube specimens to explore the degradation pattern of the ultimate bearing capacity of corroded circular steel tubes under axial compression; three were subjected to accelerated corrosion by electrification, and the other three were used as the control group. Following the accelerated corrosion test, both groups of specimens were subjected to material-property and axial-compression tests. These tests provided data on the bearing capacity and midspan displacement of the corroded circular steel tubes, allowing for the construction of load–displacement relationship curves. The test results demonstrate that corrosion significantly affects the bearing capacity of circular steel tubes. As the severity of the corrosion increased, the bearing capacity and stiffness of the corroded circular steel tubes progressively weakened. To simulate the behavior of circular steel tubes, a numerical model was established that provided the ultimate bearing capacity under axial compression and generated load–displacement curves. The simulation results closely aligned with the test results. This study introduced a novel approach for accurately computing the stability-bearing capacity of circular steel tubes subjected to corrosion and axial compression. Comparative analyzes with test results validated the superior performance of the proposed method in accurately predicting the ultimate bearing capacity.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500488
       
  • Study on the Stress Histories and Fatigue Stress Spectrums of Longitudinal
           Connected Slab Track on Bridge During Service Life

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      Authors: Qingyuan Xu, Xi Wang, Bin Li, Ze Zhang, Zilong Zhang, Lexuan Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The paper aims to study the stress histories and the fatigue stress spectrums (FSS) of longitudinal connected slab track (LCST) on the bridge during service life, and to provide an important basis for the fatigue test design of slab track (ST) in the laboratory and in situ, fatigue life prediction and fatigue designing of ST for the actual engineering. First, the temperature field model for LCST on bridge, high speed train (HST)-LCST-bridge coupling dynamic model, and LCST-bridge-piers and abutments longitudinal interaction model are established and verified. Then, based on these models, a calculation method of the FSS for the LCST on bridge under combined loads is proposed. Finally, taking the climate of the Guangzhou district in China as an example, the stress histories and FSS of LCST on a multi-span simply supported box girder bridge under combined loads are numerically simulated. The simulation results show that: (1) the stress of each component of LCST is small when considering only the vertical train load, and there will be no fatigue failure for LCST. (2) The temperature gradient load and longitudinal loads of ST significantly affect the stress distribution of LCST, so the combined effects of these loads should be considered when calculating the FSS. (3) The mechanical state of LCST is more severe around the beam end. The concrete stresses of track slab (TS) on the bottom surface and base plate (BP) on the top surface are significantly larger than the concrete stresses of TS on the top surface and BP on the bottom surface, respectively. (4) There are many peaks in the FSS of LCST on bridge under combined loads. Therefore, several probability curves should be used together to fit the FSS of LCST.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500518
       
  • Dynamic Modeling and Theoretical Analysis of Planar Nonlinear Vibrations
           of an Articulated Hoop Truss Antenna

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      Authors: Bo Fang, Yilong Wang, Yi Wu, Jae-Hung Han, Dengqing Cao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The dynamic behaviors of large-scale hoop truss antennas (HTAs) are significantly influenced by the nonlinear torque transmission properties of flexible hinges. Due to the nonlinearity of the hinge, the HTA can be easily excited to exhibit internal resonances that result in the energy exchange between the adjacent two or three modes. This paper focuses on the 3:1 internal resonant responses of an articulated HTA induced by the nonlinearity of the hinge. The analytical modes are obtained by using the global mode method (GMM) and are validated by finite element method (FEM). Then the partial differential equations (PDEs) of planar motions are discretized into ordinary differential equations (ODEs) by Galerkin’s technique. The multiple time scale method is employed to obtain the four-dimensional modulation equations of the HTA with primary and 3:1 internal resonance. By using the Newton–Raphson iteration and the pseudo arclength continuation, frequency–response and force–response curves are obtained to investigate the theoretical steady-state vibrations of the HTA. Moreover, the influence of the cubic spring stiffness, damping, and external excitation amplitude on the system’s nonlinear dynamic behaviors are investigated. The numerical simulation reveals that the articulated multi-beam hoop structure exhibits typical nonlinear phenomena such as hardening-spring type characteristic, jumps, bi-stability, and double peaks. The research findings contribute to the reliable structural design and vibration control of the articulated hoop truss antenna.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500531
       
  • Fatigue Damage Analysis of Steel Truss Suspension Bridge Under
           Non-Stationary and Non-Gaussian Buffeting

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      Authors: Jun Hu, Xinqi Zhang, Shaohua Tan, Yongyong Liang, Junhan Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The wind field environment in mountainous zones is complex. If the wind field characteristics are regarded as stationary and Gaussian, the inaccurate response results of the structure will be obtained. In this paper, a fatigue evaluation method of steel truss suspension bridge members under non-stationary and non-Gaussian buffeting is proposed. This approach can solve the fatigue evaluation problem of steel truss suspension bridge members under mountain wind. Firstly, the normal wind speed (stationary and Gaussian) is obtained by the harmonic wave synthesis method. The wind speed considering non-stationary characteristics is obtained by adopting time-varying power spectrum. Secondly, through non-linear translation, the wind speed considering non-stationary characteristics is transformed into wind speed considering both non-Gaussian and non-stationary characteristics. Finally, combined with the Palmgren–Miner rule, the effects of three different buffeting responses on fatigue damage of suspension bridge members are studied. They are traditional buffeting response, buffeting response considering non-stationary characteristics and buffeting response considering both non-stationary and non-Gaussian characteristics. The results indicate that the fatigue damage of the main cable of the suspension bridge is the biggest at the mid-span. Under the same wind speed, considering two characteristics, the component fatigue damage will further increase.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500555
       
  • Effect of Bearing Friction on Seismic Performance of Bridges with Massive
           Piers Isolated by Friction Pendulum Bearings

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      Authors: Xinyan Jiang, Jianzhong Li, Nailiang Xiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Although seismic isolation is a well-accepted design strategy for bridges to provide structural earthquake resistance, for bridges with massive piers, it may unexpectedly pose an abnormal influence on the seismic response of bridges due to the effect of substructure mass. This study investigates the effects of bearing friction and pier mass on the seismic performance of bridges isolated by friction pendulum bearings (FPBs). Nonlinear time history analysis is conducted to demonstrate the variation of the bridge peak responses with different bearing frictional coefficients and pier mass. The inherent influential mechanism of the frictional coefficient of FPBs is also discussed in the current study. The results of the analysis show that for FPB-isolated bridges with massive piers, the peak base shear forces of piers first decrease and then increase with the increase of the bearing frictional coefficient. Such a phenomenon may be attributed to the fact that the inertia force of the massive piers will be altered by the variation of bearing friction. The outcome of this study provides a useful reference for practical engineering that the seismic base force of massive bridge piers calculated under a specified bearing frictional coefficient may be smaller than the actual response and cause reduced safety to bridges.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-28T07:00:00Z
      DOI: 10.1142/S0219455425500567
       
  • Numerical Studies on Low Velocity Oblique Impact Analysis of Silicon
           Aluminum Composite Foam

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      Authors: T. Thimmesh, G. Narayana Naik, Dinesh Kumar Harursampath
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In the impact application, the impactor doesn’t have to be perpendicular to the structure. This study mainly focuses on numerical low velocity oblique impact analysis performed on silicon aluminum composite foam using ABAQUS[math]. In this paper, the shear failure model is used to estimate damages in silicon aluminum composite foam model for different angles of the impactor. Here, dissipation energies, impact load histories and load displacement curves for damages under different angles of impactor have been characterized. From the study, it is found that the contact force intensity and penetration time decrease as the angle of the impactor increases. In the study of energy time histories, it is seen that energy increases and penetration time decreases as the angle of the impactor increases. From the contact force study, it is found that the contact force decreases, and contact time increases as the angle of the impactor decreases. The studies for displacement show that oblique impactor displacement increases as the angle of the impactor increases.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455424400200
       
  • Running Safety Assessment of a High-Speed Train on Bridges During Braking
           Under Near-Fault Ground Motions

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      Authors: Hongkai Ma, Xiaonan Xie, Han Zhao, Binbin Yin, Ping Xiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study aims to investigate the adverse effects of near-fault ground motions on the long-term development of high-speed railways. In this paper, the ground motions are analyzed based on the Train–Track–Bridge Coupling Braking System (TTBCBS) which has been validated during earthquakes. The effects of earthquakes on the whole system are discussed in depth, focusing on the random nature of earthquakes, the impulsive character of near-fault earthquakes and the effects of different initial speeds on the system behavior. The results show that under random earthquakes, the probability of train derailment gradually increases with the increase of peak ground acceleration (PGA) of earthquakes. When the PGA exceeds 0.2[math]g, the train is highly susceptible to derailment and the bridge itself may incur damage. When analyzing the nature of pulses of near-fault ground motions, it was found that the responses induced by class B and class C pulses are significantly similar. Meanwhile, the calculated values of derailment coefficients are basically the same when the PGA of class A pulse wave is at 0[math]g and 0.1[math]g. This suggests that train braking somewhat mitigates the response induced by near-fault ground motions. Furthermore, the value of improved spectral intensity (SI) for the running safety during earthquakes indicates that the increase in seismic intensity is detrimental to the system. In terms of the effect of train initial speeds on the system during earthquakes, it is observed that the system response reaches the lowest point when the train speed is 250[math]km/h, which is more favorable to the smooth deceleration of the train. When the train speed is 400[math]km/h, the system response reaches its maximum value. These research findings provide crucial insights and guidance for seismic safety design and management of high-speed railways.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455424502298
       
  • Vibration Mitigation via Tuned Mass Damper for Adjacent Stay Cables
           Interconnected with Rigid Cross-Tie

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      Authors: Xidong Wang, Wei Gou, Wudi Gao, Shengli Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The characteristics of low damping and closely spaced natural frequencies make stay cables susceptible to wind-induced vibrations. This work proposed a novel damping device consisting of tuned mass damper (TMD) and rigid cross-tie (RCT) to mitigate the vibration of stay cables effectively. Two adjacent stay cables interconnected with RCTs can provide installation locations for TMDs, thus making the novel TMD-RCT control system feasible. Experimental control tests were carried out on a two-cable model of adjacent stay cables built in laboratory, where one TMD was designed based on the fundamental vibration mode of the stay cable. The effects of CT stiffness, number of RCTs, mass ratio, and installation position on the vibration reduction effect of the device were studied. To validate the efficacy of the proposed TMD-RCT device in vibration mitigation of stay cables under different loading cases, simulation tests and corresponding control performance evaluation were conducted.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455424502377
       
  • Study of Support Motion of a Finite Bar with a Boundary Damper and a
           Spring Using Analytical Approaches and FEM

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      Authors: Jeng-Tzong Chen, Hao-Chen Kao, Jia-Wei Lee, Ying-Te Lee
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, we solve the vibration problem of a finite bar with a viscously damped boundary in conjunction with a spring on the same side subject to the support motion on the other side. To avoid the computation of complex modes and the difficulty of orthogonal conditions for the partial differential equation (PDE) of a continuous system, two alternatives are employed. One is the analytical derivation by using the diamond rule of the method of characteristics. The advantage is that this method can yield an analytical solution. However, the disadvantage is that the method can be only applied to some simple problems such as a linear system and the one-dimensional (1D) wave equation. The other numerical method, finite element method (FEM), is incorporated into a general-purpose program to solve this problem. The advantage of the FEM is that this methodology can be applied to solve various problems such as different PDEs. Therefore, the solution obtained by using the FEM is compared with that of the analytical solution. Two special cases, only a spring and a damper alone, are also considered by using the FEM. Interestingly, the same silent area is captured in the displacement profile by using the FEM for the three cases. We also find that the displacement profiles have slope discontinuity which only occurs on the characteristic line. After the wave front arrives at the boundary, various responses appear due to different boundaries, spring, damper and both. It is found that the displacement amplitude of the general case is smaller than the other two special cases. This result matches the application of engineering practice.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S021945542550035X
       
  • Progressive Collapse Analysis of Single-Layer Latticed Domes Under Seismic
           Loading Using Enhanced Fiber-Based Approach

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      Authors: Yuxiang Cai, Yanfeng Zheng, Jingzhe Tang, Yaozhi Luo, Chao Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a novel computational framework based on the Finite Particle Method (FPM) for the progressive collapse analysis of single-layer latticed domes subjected to seismic loading. The framework integrates a fiber-based approach to simulate the nonlinear behavior of steel structural members, including yielding, cyclic buckling, and fracture. For structural seismic analysis, the fiber-based approach is enhanced by incorporating a dynamic increase factor, which accounts for the impact of high strain rates during seismic events. Furthermore, the framework extends the pseudo-dynamical stiffness of the particle to consider Rayleigh damping, surpassing the limitations of the original mass damping model. The computational efficiency of the proposed framework is optimized by implementing it on a generic parallelized GPU platform. The computational framework has the advantage of elaborately simulating the response of individual structural members while efficiently capturing the complex behavior of the overall structure. Subsequently, the effectiveness of the enhanced framework is demonstrated through the analysis of the collapse behavior of a representative single-layer latticed dome under seismic loading. The study conducts a parametric analysis to evaluate the influence of two key factors, namely, rise-to-span ratios and imperfections, on the collapse behaviors. The findings contribute to a better understanding of the complex behaviors of single-layer latticed domes during seismic events, providing knowledge for improving structural safety and resilience in public buildings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455425500385
       
  • Enhancing Cable Vibration Measurement at Long Distances Through
           Super-Resolution Reconstruction and Target Foreground Segmentation

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      Authors: Depeng Cui, Weidong Wang, Jun Peng, Yukun Zhang, Yida Zhao, Bin Chen, Yan Liu, Jin Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a comprehensive non-contact computer vision-based system for monitoring cable vibrations in cable-supported bridges, addressing challenges related to low image resolution and feature extraction difficulties at long distances. The proposed system utilizes deep learning techniques to enhance cable vibration recognition accuracy and offers a practical solution for cable monitoring without the need for target assistance. The core of the system is a novel two-stage model, which combines a super-resolution (SR) video reconstruction algorithm with state-of-the-art Resnet-34 and Swin-B models for precise target foreground segmentation. This approach significantly improves the recognition of target details and enhances the accuracy of cable vibration data in monitoring videos. Furthermore, a phase-based motion estimation (PME) algorithm is employed for precise cable vibration measurement. Field tests conducted on two cable-supported bridges validate the effectiveness of the system. The results demonstrate superior accuracy and noise immunity compared to traditional methods, achieving sub-pixel level precision with a maximum error rate below 2%. This system represents a significant advancement in non-contact structural health monitoring for long-distance cable vibration monitoring in cable-supported bridges.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455425500397
       
  • Numerical Study on Seismic Performance of Rocking Self-Centering (RSC)
           Bridge Piers Under Bidirectional Excitation

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      Authors: Li Jiang, Chao-Yang Ge, Peng-Cheng Zhou, Zhi-Guo Sun, Jia-Jun Liu, Yan-Hui Liu, Dong-Sheng Wang, Xiao Ge
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To study the seismic performance of rocking self-centering (RSC) bridge piers, a numerical model of RSC pier is established based on the OpenSees platform. The model is verified by experimental results. The seismic performance of RSC piers is analyzed under quasi-static and seismic loads, respectively, in terms of peak lateral drift, residual deformation, compressive zone height of the cross-section and tendon stress. Far-field, near-field without pulse and near-field pulse-like ground motion records are selected for the time-history analysis. The effects of prestressing tendon reinforcement ratio, energy-dissipating bar ratio and axial load are examined, respectively. The results show that the strength of the RSC pier, the depth of the compressive zone of the cross-section and the self-centering capacity increase with increasing prestressing tendon reinforcement ratio. When the energy-dissipating reinforcement ratio exceeds 1%, the boost of seismic performance of the pier becomes insignificant. The increasing axial load can increase the lateral strength of the pier. However, it could lead to premature yielding of the prestressing tendons.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455425500415
       
  • Experimental Investigations on the Residual Performance of
           Earthquake-Damaged Low-Rise-Reinforced Concrete Shear Walls

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      Authors: Wen-I Liao, Yu-Ming Zheng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study investigates the seismic residual performance of reinforced concrete (RC) shear walls with different levels of earthquake damage through reversed cyclic loading tests. The test specimens include slightly damaged walls, moderately damaged walls, and repaired specimens after moderately damaged walls. From the test and analysis results, it is evident that the residual strength and deformation capacity of slightly and moderately damaged RC shear walls do not decrease compared with the undamaged wall. However, the residual stiffness and energy dissipation capacity of damaged walls significantly decrease. The test results are also compared with the reduction factors for residual stiffness, strength, deformation capacity, and energy dissipation capacity in the FEMA 306 and JBDPA post-earthquake assessment guidelines to assess their applicability. Additionally, this study proposes a simplified model to describe residual lateral capacity curves of damaged RC walls at different damage levels for nonlinear pushover analysis, allowing engineers to easily convert the capacity curves of undamaged walls to damaged ones.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-27T07:00:00Z
      DOI: 10.1142/S0219455425500506
       
  • Testing, Modelling, and Performance Evaluation of a Rotary Eddy-Current
           Damper with Inherent Nonlinear Damping Characteristics for Structural
           Vibration Control

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      Authors: Zhipeng Cheng, Zhihao Wang, Kaiming Bi, Kaiqiang Cui, Hui Gao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the inherent nonlinear damping characteristics of a rotary eddy-current damper (RECD) and evaluates its vibration control performance on a single-degree-of-freedom (SDOF) system subjected to harmonic and seismic excitations. First, a RECD prototype was manufactured to experimentally identify its intrinsic nonlinear eddy-current damping characteristics. A magic formula model is then proposed to characterize the relationship between the eddy-current damping force and the velocity of the RECD, and its applicability in depicting the nonlinear damping characteristics of the RECD is evaluated by comparing with the electromagnetic finite-element (FE) model and the commonly used Wouterse’s model. Moreover, by comparing the experimental and analytical frequency–domain responses of an SDOF structure equipped with a RECD, the applicability of the magic formula model in evaluating the structural vibration control performance of the RECD is further verified. Finally, the control performance of the RECD for an SDOF structure subjected to earthquake ground motions is numerically evaluated and compared. Results show that the eddy-current damping force of the RECD presents obvious nonlinear characteristics with increasing velocity, and the proposed magic formula model can adequately depict the nonlinear eddy-current damping characteristics of the RECD. Moreover, the RECD exhibits superior structural control performance under harmonic and seismic excitations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-25T07:00:00Z
      DOI: 10.1142/S0219455424502134
       
  • Influence of the Seabed Site and Island Structure on Seismic Response of
           Marine Artificial Islands

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      Authors: Baokui Chen, Kailin Bu, Bowei Wang, Yan Shi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Compared with the marine structures such as sea-crossing bridges and offshore wind turbines, the marine artificial islands are bottom sitting structures and particularly sensitive to site conditions. Therefore, the study focuses on determining the effect of seabed site conditions and construction methods on the seismic performance of marine artificial islands. A seismic wave analysis model of seabed-seawater layer–artificial island coupling is developed by combining the self-programmed fluctuation analysis program and the dynamic analysis software. Firstly, the seismic response of marine artificial islands with different site conditions are analyzed by inputting P and SV waves. On that basis, the effects of incidence angles on the seismic response are explored. Then the study further explores the effects of different backfill materials and protective structures on the seismic response of the artificial island. Numerical results show that the silty soft soil layer can amplify the seismic response of seabed sites, and this amplification effect increases with the increase of the depth of silty soft soil layers. Moreover, the coral sand as backfill material can reduce the seismic response of marine artificial islands. The seismic response of marine artificial islands can also be reduced in the model with a protection structure. These results will provide some theoretical references for the site selection and construction method of marine artificial islands.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-25T07:00:00Z
      DOI: 10.1142/S0219455425500026
       
  • Experiment, Simulation, and Theoretical Investigation of a New Type of
           Interlayer Connections Enhanced Viscoelastic Damper

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      Authors: Yeshou Xu, Zhao-Dong Xu, Hao Hu, Ying-Qing Guo, Xing-Huai Huang, Zhong-Wen Zhang, Tian Zhang, Chao Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A conventional plate-type viscoelastic damper (VED) can easily crack at the interfaces of steel plates and viscoelastic components. In the present work, grooved VEDs, which are a new type of interfacial enhanced VEDs with interfacial grooves, are designed to improve the damping capacity and anti-cracking ability of conventional dampers. The dynamic property experiments of the normal and grooved VEDs are carried out and the interfacial cracking failure of the VEDs are simulated and analyzed by using bilayer cohesive constitutive model with ABAQUS. The grooved VED exhibits excellent dynamic performance and energy dissipation capacity at different temperatures, frequencies, and displacement amplitudes. Experiments and finite element analysis prove that the energy dissipation performance and interfacial bonding strength of the grooved VED are effectively improved. A modified fractional standard linear solid model, in which the Payne effect and temperature–frequency equivalent principle are combined and implemented, is proposed. This model can portray the influence of the excitation displacement, surrounding temperature and external excitation frequency on damper properties at the same time. The fillers and molecular chains affections at micro- and meso-scale are also taken into account. The model’s numerical calculations and experimental results comparisons present that the modified fractional standard linear solid model has sufficient accuracy and performs well in depicting the dynamic properties of the interfacial grooved VED. The errors between the theoretical and experimental values of [math] and [math] for the grooved VED are mostly within 20% at representative conditions. The interfacial groove structures can well enhance the interfacial bonding and improve the service life of conventional dampers. The modified fractional standard linear solid model is simple and has clear physical meanings for each macro/micro parameters, making it convenient for application in engineering practice. The present research is of great significance in improving the work stability of VEDs and promoting the application of viscoelastic damping technology.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-25T07:00:00Z
      DOI: 10.1142/S0219455425500452
       
  • Effects of Concentrated Mass on the In-Plane Dynamic Behaviors of
           Two-Cable Networks with a Cross-Tie

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      Authors: Fangdian Di, Chenyu Zhang, Jun Yin, Limin Sun, Lin Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes a two-cable network model, which includes a cross-tie and two concentrated masses installed at the connection points of cross-tie and cable. The characteristic equation of such a cable network system is formulated via the complex modal analysis method. Then, dynamics of a twin-cable network is discussed in details, and the effect of concentrated mass on the system modal frequencies, damping and mode shapes is investigated. Furthermore, a general two-cable network system is analyzed. Results show that the concentrated mass always reduces the modal frequency, as it causes an increase in the modal mass of the system. When installing a concentrated mass in a twin-cable network, the difference of vibration modes between the cables can be increased in the in-phase modes, thereby achieving the damping effect of the damping type cross-tie on these modes. For a twin-cable network with a viscous damper, a small concentrated mass can significantly increase the modal damping of the in-phase modes as long as the damping coefficient of the damper is properly set. Meanwhile, when there is a two-cable network with unequal length cables, the presence of concentrated masses may reduce differences in vibration modes between cables, thus leading to decreased damping of some modes.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-25T07:00:00Z
      DOI: 10.1142/S0219455425500464
       
  • Transient Aerodynamic Heating Effects on Aeroelastic Dynamic Response of
           Curved Fiber-Reinforced Composite Panel in Supersonic Airflow

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      Authors: Yating Liu, Jingbo Duan, Buqing Xu, Jiaqi Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The nonlinear aero-thermo-elastic behaviors of the curved-fiber composite panel are studied accounting for transient aerodynamic heating effects with two-way coupling method. The Von Karman assumption is utilized to depict the large deflection of the composite panel and the supersonic aerodynamic load is incorporated through first-order piston theory, respectively. The aerothermal and aeroelastic models are coupled with each other by performing the iterative procedure in the time domain. The aerodynamic heating heat flux is obtained by the Eckert reference temperature method, the transient temperature field is solved by the finite difference method, and the aeroelastic dynamic response is solved by the combination of the Newmark method and Newton–Raphson method. The accuracy and validity of the established model are justified by comparing the present solutions with the present numerical results in published literature. Then, the influences of the key parameters such as the transient temperature field, coupling step, heat transfer coefficient, shock wave, initial disturbance force and fiber configurations on aerothermoelastic responses of the composite panel respectively are discussed in detail.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-25T07:00:00Z
      DOI: 10.1142/S021945542550052X
       
  • Vibration Mitigation Using 3D-PSTMD for the Offshore Wind Turbine
           Considering Self-Excitation Behaviors

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      Authors: Gang Liu, Zhenbo Lei, Yujia Liang, Wei Tang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The self-excitation behaviors can be triggered by the blade rotation of the wind turbine. To mitigate the excessive vibration of offshore wind turbine (OWT) tower under this self-excitation addition with wind–wave loadings, a three-dimensional prestressed TMD (3D-PSTMD) is extended in this study. First, based on the Lagrange equation, the analytical formulations of 1P (rotor rotational speed) and 3P (blade passing frequency) loads from self-excitations are deduced, and more factors under real operational conditions of the OWT are further analyzed using theoretical derivation and numerical simulation. Then, structural aero-hydrodynamic loadings are modelled, and self-resonance phenomenon of the uncontrolled OWT and resonance dissipation capability of 3D-PSTMD are discussed at startup–operation–shutdown state. Finally, the energy harvesting competence of 3D-PSTMD is quantitatively calculated via the classical Wilson-[math] algorithm under self-excitations with wind–wave loadings. Results indicate that this dashpot is remarkably able to mitigate the structural resonance responses over 61.3% and 40.5% respectively when under the 1P and 3P loadings, and it can also effectively reduce the bi-directionally horizontal vibrations of OWT under aero-hydrodynamic loadings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-22T07:00:00Z
      DOI: 10.1142/S0219455425500439
       
  • Vibration Suppression of Piecewise-Linear Stiffness Nes System Under
           Random Excitation

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      Authors: Jun Wang, Zi Jian Kan, Yun Hao Zhang, Jian Chao Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Nonlinear energy sinks (NESs) are critically important for structural vibration suppression. They can absorb vibrational energy across a broad frequency spectrum, possess strong robustness, and have a relatively small mass. This study addresses the vibration suppression in a piecewise linear stiffness NES system under random excitation. Initially, a theoretical model of the piecewise linear stiffness NES system is developed. The piecewise linear stiffness function is approximated using Legendre polynomial approximation. Following this, the steady-state Fokker–Planck–Kolmogorov (FPK) equation of the system is formulated via the Generalized Harmonic Function Method. The FPK equation is solved using the fourth-order central difference method, and the effectiveness of this approach is validated by comparing the FDM results with numerical simulations. Lastly, the influence of varying system parameters on the stability of the piecewise linear stiffness NES system is analyzed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-22T07:00:00Z
      DOI: 10.1142/S0219455425500440
       
  • Nonlinear Optimized PID Vibration Control of Thermal-Dependent FG
           Composite Porous Plates Reinforced by Agglomerated CNTs

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      Authors: Juan Li, Juanyin Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This research study aims to delve into the effects of carbon nanotubes (CNTs) agglomeration on the dynamic characteristics of smart functionally graded (FG) porous sandwich plates. The structure of the sandwich plate comprises a core layer that incorporates dispersed CNTs within a polymer matrix. In addition, two layers are equipped with piezoelectric sensors and actuators. The agglomeration of CNTs is mathematically modeled using the Eshelby–Mori–Tanaka approach, accounting for both complete and partial agglomeration states. Moreover, the study takes into account the thermal-dependent behavior of CNTs. Subsequently, an optimal nonlinear proportional-integral-derivative (PID) control scheme based on the Bat optimization algorithm is applied to mitigate vibrations within the composite structure. Unlike the fixed gains of the classical PID, the nonlinear version dynamically adjusts its parameters in real time, ensuring enhanced responsiveness and stability. Furthermore, a comprehensive numerical investigation is conducted to assess the impact of several parameters on the natural frequencies in the frequency domain. These parameters encompass porosity distributions, porosity coefficients, reinforcement patterns, weight fractions of nanofillers, temperature, and the agglomeration of CNTs. The vibration attenuation performance of both nonlinear and classical PID controllers is evaluated through numerical simulations. The findings indicate the robustness and rapid disturbance rejection of the proposed control scheme.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-20T07:00:00Z
      DOI: 10.1142/S0219455425500348
       
  • Frequency Design of a Vertical Cantilever Beam Carrying Tip Mass

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      Authors: Shengli Chen, Zhiqiang Wu, Yijia Zhang, Hanlu He
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Previous research has revealed that vertical cantilever beam structures, after considering the effects of gravity, can exhibit a 1:3 internal resonance between two transverse modes. However, whether a similar phenomenon would still occur in the system when a proof body is attached to the free end of cantilever beams, and how to perform parameter design to deliberately induce internal resonance are still open issues. The present study conducts research on the natural frequencies of a vertical cantilever beam with a tip mass. Within the framework of the Euler–Bernoulli beam theory, Hamilton’s principle is utilized to derive the integral-partial differential equation of free vibration of the system. The corresponding frequency equation is then solved using the Chebyshev pseudospectral method, with an algebraic equation of the natural frequency obtained. Moreover, an explicit analytical expression for the fundamental frequency is obtained using parameter fitting, which is then used to reveal the relationship among parameters under the critical state of buckling and evaluate the extent of gravity’s impact on the fundamental frequency. The study finally investigates the ratio of the first two natural frequencies. A parameter design method is proposed, which derives a parametric curve in terms of the fundamental frequency, ensuring a 1:3 ratio between the first two natural frequencies. The free vibration time history at the midpoint of the beam is acquired by directly solving the systems partial differential equation through the finite element method. Fourier transformation of this time history verifies that the fundamental frequency aligns with a predetermined value, and the ratio between the first two natural frequencies is 1:3, thus confirming the efficacy of the proposed method. It is found that the addition of a tip mass provides more flexibility in adjusting parameters to achieve internal resonance, which facilitates the miniaturization of actual structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-16T07:00:00Z
      DOI: 10.1142/S0219455424300027
       
  • Metro Monolithic Track Bed Vibration Characterization

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      Authors: Kaiyun Lei, Linchang Miao, Haizhong Zheng, Peng Xiao, Qian Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      With the rapid development of cities, metro transportation has also developed rapidly to solve the congestion problems caused by urban development. However, with the continuous development of metro transportation, the vibration problems caused by it have become increasingly obvious. Based on the phonon crystal theory, this paper investigates the vibration characteristics of the metro track structure. It analyzes the influence of the track structure parameters on the band gap characteristics to regulate the metro vibration band gap range. To study the band gap characteristics of metro monolithic bed track structure, establish the double-layer Euler beam model and use the plane wave expansion method (PWE) to calculate its energy band structure; use the finite element method (FEM) to calculate to get its band structure, frequency response function, and time domain analysis. The calculation of PWE shows that there is a band gap in the range of 0–300[math]Hz for the metro monolithic track bed, which is 0–194.5[math]Hz; the calculation of FEM shows that the range of band gap is 0–193.7[math]Hz. Fastening spacing, stiffness, and sub-slab support stiffness will have an impact on the band gap, so appropriate fastening and spacing need to be selected for effective vibration damping of the track structure. The results show that the band gap characteristics of the metro monolithic track bed can be calculated effectively and accurately by using the phononic crystal theory.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-16T07:00:00Z
      DOI: 10.1142/S0219455424502444
       
  • Bridge Damage Identification Based on LSTM Network and Contact Point
           Response

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      Authors: Xinfeng Yin, Yuecheng Yang, Zhou Huang, Wanli Yan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a bridge damage identification method based on the Long Short-Term Memory (LSTM) network and the contact point response is proposed, which utilizes the time behavior of the contact point response. The contact point response serving as the input to the LSTM network is obtained by calculating the vehicle-bridge interaction motion equation. A new bridge damage indicator titled the Euclidean Distance Damage Index (EDDI) is developed based on the difference between the actual and predicted values of the contact point response. Under ideal road surface conditions, the EDDI calculated in the healthy state of the bridge remains below 0.16, while exceeding 1.0 in the damaged state. When road roughness is considered, the EDDI is calculated to be less than 0.12 in the healthy state of the bridge and higher than 0.65 in the damaged state. The results show that the EDDI is more effective in distinguishing between the damaged and the healthy states of the bridge. Meanwhile, road roughness has a negative effect on the damage sensitivity of EDDI.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-16T07:00:00Z
      DOI: 10.1142/S0219455424502687
       
  • Energy Absorption Characteristic of Biomimetic Gradient Hierarchical
           Multicellular Tubes Under Axial Impact

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      Authors: Jun Qian, Xiaolin Deng, Cuiping Huang, Zhenzhen Cai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper introduces a biomimetic gradient hierarchical multicellular structure consisting of two tree-like fractal variants: one based on vertex connections (HCV) and the other based on wall connections (HCW). We investigate their mechanical behavior and deformation through numerical simulations. Our findings reveal that, irrespective of whether they have the same wall thickness or mass, second-order and third-order structures exhibit superior energy absorption capacity (EA) and crushing force efficiency (CFE) compared to first-order structures, resulting in significantly enhanced crashworthiness performance. In the case of HCV structures with identical wall thickness, the third-order structure outperforms the first-order structure by 79.73% in specific energy absorption (SEA) and by 38.51% in CFE. Similarly, for HCW structures, the third-order variant surpasses the first-order one by 45.57% in SEA and 28.39% in CFE. We also conduct a parametric study, exploring the influence of inner circle diameter, fractal coefficient, and fractal angle on the crashworthiness of biomimetic gradient hierarchical multicellular structures. We identify the optimal fractal coefficient and inner diameter distribution range for HCV when the fractal angle is 60°. Lastly, we compare these structures with traditional multicellular tubes, demonstrating that biomimetic gradient hierarchical multicellular tubes achieve up to 50.34% higher SEA and 55.13% higher CFE. The results of this study offer valuable design insights for developing lightweight and efficient energy-absorbing structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-16T07:00:00Z
      DOI: 10.1142/S0219455425500300
       
  • Nonlinear Geometrical Effect on Deflection Characteristics of Fiber/Metal
           Laminates

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      Authors: Bhabatosh Panda, Vikash Kumar, Ashish Kumar Meher, Subrata Kumar Panda
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The deflection behavior of the fiber-metal laminated structures is envisaged in this research using higher-order deformation kinematics and large (finite) deformations of geometries via Green–Lagrange strain. The panel governing equation is derived using variational principle and solved numerically considering the nonlinear finite element (FE) steps. The necessary responses are obtained using in-house MATLAB computer code and compared with an in-house simulation model (prepared in ANSYS) and experimental data (using in-house experimental set-up). The results are verified and agree with the published data available in the open domain. The proposed model results show better consequences compared to the simulation results. The detailed responses are computed for the variable geometrical conditions (i.e. aspect ratio, end support, side-to-thickness ratio), loading and stacking sequences, including the metal layer placing. The inferences indicate the importance of nonlinearity in the framework of a higher-order kinematic model for analysing the metal laminated structure.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-16T07:00:00Z
      DOI: 10.1142/S0219455425500373
       
  • Vibration Behavior of Composite Cold-Formed Steel Floors with Concrete
           Topping due to Heel-Drop Loading

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      Authors: Yu Shi, Yao Wei, Jiang Li, Honglong Li, Y. Frank Chen, Yunfei Zhao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Human-induced vibration is an important serviceability issue of modern structural designs, especially for light long-span structures. The common heel-drop impact is usually considered in evaluating the vibration of cold-formed steel (CFS) floors. This paper proposes a simplified equation for determining the peak accelerations under transient impacts, based on the Duhamel integral. The analytical results were validated with a comparison with the results from the heel-drop test results on a CFS floor of 3 900[math]mm × 5 600[math]mm (at both construction and completion stages). The dynamic responses of the floor, including peak acceleration, maximum transient vibration value (MTVV), and crest factor (a ratio of MTVV-to-peak acceleration) were analyzed in detail. The natural frequencies of the floor were obtained from the FFT and FRF analysis of heel-drop and hammering test results. The investigated on-site composite CFS floor with concrete topping was found to have a high fundamental frequency: 17[math]Hz at the construction stage and 21[math]Hz at the completion stage. In determining the fundamental frequency of the CFS floor, the hammering was thought to be more effective than the heel-drop owing to the phenomenon of human-structure interaction (HSI). Moreover, finite element analyses were performed to study the effects of profiled steel sheeting type (Types 28-100-800, 21-180-900, and 14-80-640) and concrete thickness (40, 50, 60, 70, 80, 90, and 100[math]mm). With the SCSC condition (two opposite edges clamped and the other two edges simply-supported), the peak acceleration decreased by 50% when the concrete thickness increased from 40[math]mm to 100[math]mm.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-14T07:00:00Z
      DOI: 10.1142/S0219455425500269
       
  • In-Plane Vibrations of Deep Sandwich Arches with Different End Conditions
           Based on a Logarithmic Shear Deformation Theory

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      Authors: Yingying Zhang, Jishen Peng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper deals with the vibrational frequencies of deep sandwich arches to enhance their application domain and possibly use them for energy harvesting. The circular arch with porous nanocomposite core and titanium alloy face sheets having different end conditions is numerically analyzed. The middle core of the sandwich arch is made of a six-layered porous aluminum reinforced with graphene nanoplatelets. The kinematic equations are formulated in this study based on the higher-order shear deformation theory using a logarithmic function of radius. The effective properties of the nanocomposite media are modeled by employing the Halpin–Tsai modified rule. The equations of motion are determined by applying the principle of virtual displacement. The partial differential equations are reduced using the generalized differential quadrature technique to solving an algebraic eigenvalue problem. Novel numerical results are given to show the effects of geometrical parameters, material properties, and boundary conditions on the vibrations of deep sandwich arch.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-14T07:00:00Z
      DOI: 10.1142/S0219455425500294
       
  • Dynamic Analysis of a Double-Cable-Stayed Shallow Arch Model Under
           Multi-Frequency Excitation by IHB Method

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      Authors: Yunyue Cong, Shiyu Jin, Houjun Kang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To reveal the dynamic properties of cable-stayed bridges under complex external excitations, a double-cable-stayed shallow arch model induced by multi-frequency harmonic excitations is established. The cable and shallow arch exhibit primary or subharmonic resonances by sweeping excitations simultaneously and asynchronously. Galerkin method, one/two time scales Incremental Harmonic Balance (IHB) method, and Runge–Kutta (RK) method are applied to explore the nonlinear dynamic responses. Research results demonstrate that both the cables and shallow arch present soft and hard spring properties, despite the very weak hard spring of the shallow arch; one-way dynamic interaction among the cables and the shallow arch is discovered when sweeping excitations asynchronously.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-14T07:00:00Z
      DOI: 10.1142/S0219455425500336
       
  • Experimental Study on the Mechanical Properties of Nylon Fabric-Reinforced
           Elastomeric Isolators (N-FREIs)

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      Authors: Yifeng Wu, Kai Fan, Aiqun Li, Ben Sha, Mingfei Si, Song Lu, Hao Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In recent decades, carbon fiber, glass fiber, polyester and Kevlar fiber have been utilized to replace the steel shims in conventional steel-reinforced elastomeric isolators (SREIs). This study chose nylon fabrics owing to their extreme low cost, low elastic modulus and good adhesion to rubber, and nine nylon fabric-reinforced elastomeric isolators (N-FREIs) were manufactured with different design parameters. Compression and compression shear tests were, respectively, conducted to investigate the mechanical properties together with their influential factors of the N-FREIs. Results show that the vertical load-carrying capacity of the isolator is high enough to sustain a compressive stress of 10[math]MPa without visible damage. The compressive stiffness of N-FREI is much smaller than that of SREI, and the vertical damping ratio under cyclic compression reaches up to 7%. In the compression shear tests, the shear stiffness of the isolator first decreases and then increases as the shear strain increases within 300%, and the equivalent damping ratio varies between 9% and 14% for different sizes of the isolator. Additionally, due to the flexibility and extensibility of the low modulus nylon fabric, both vertical and horizontal stiffness decrease a bit with an increase in the number of fabric layers. Finally, a formula for calculating the horizontal stiffness of N-FREI is proposed, it provides a comprehensive mathematical model to predict the behavior of the N-FREI under horizontal shear conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-13T07:00:00Z
      DOI: 10.1142/S0219455425500208
       
  • Linear and Nonlinear Dynamics Responses of an Axially Moving Laminated
           Composite Plate-Reinforced with Graphene Nanoplatelets

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      Authors: S. F. Lu, N. Xue, W. S. Ma, X. J. Song, X. Jiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The subharmonic resonances of an axially moving graphene-reinforced laminated composite plate are studied based on the Galerkin and multiscale methods. Graphene nanoplatelets (GPLs) are added into matrix material which acts as the basic layer of the plate, and a graphene-reinforced nanocomposite plate is thus obtained. Different GPL distribution patterns in the laminated plate are considered. The Halpin–Tsai model is selected to predict the physical properties of the nanocomposite. Hamilton’s principle is utilized to conduct the dynamic modeling of the plate and the von Kármán deformation theory is used. The velocity is assumed to be a combination of constant and harmonically varied velocities. The natural frequencies of the linear system with constant velocity can be obtained using the eigenvalues of the coefficient matrix of the ordinary differential equations after the governing partial differential equations of motion are discretized through the Galerkin method. The instability regions of the linear system and the amplitude–frequency relations of the nonlinear system considering the harmonically varied velocity are obtained based on the multiscale analysis. The effect of GPL reinforcement on the subharmonic resonances of the linear and nonlinear systems is analyzed in detail.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-13T07:00:00Z
      DOI: 10.1142/S0219455425500361
       
  • Multimodal Resonance Response of Incompressible Hyperelastic Moderately
           Thick Cylindrical Shells

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      Authors: Zhentao Zhao, Jiayan Lin, Jie Xu, Xuegang Yuan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Based on the modified third-order shear deformation theory, the harmonic balance method, and the pseudo-arclength continuation method with two-point prediction, the nonlinear forced vibration response of incompressible hyperelastic moderately thick cylindrical shells subjected to a concentrated harmonic load at mid-span and simply supported boundary conditions at both ends is investigated. The algorithmic procedure for solving steady-state periodic solutions of strongly nonlinear systems of differential equations is presented. The structural response characteristics of shells under different excitation amplitudes and structural parameters are analyzed. The numerical results indicate that the aspect ratio of moderately thick hyperelastic cylindrical shells has a significant effect on the natural frequency ratio. Different frequency ratios lead to varying nonlinear mode coupling effects. The coupling effects among modes result in complex nonlinear behavior in the vibration response of each mode, leading to abundant multi-valued phenomena in the response curve.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-11T07:00:00Z
      DOI: 10.1142/S0219455425500282
       
  • 1/2 and 1/3 Subharmonic Resonance Behaviors of a Rotating FG-CNTRC Beam
           with Geometric Imperfections

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      Authors: Bai-Chuan Lin, Zhen-Ming Su, Kai Qian, Hao Dong, Peng-Fei Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper aims at investigating 1/2 and 1/3 subharmonic resonances of a rotating functionally graded carbon nanotube-reinforced composite (FG-CNTRC) beam in the presence of geometric imperfections. A general function is introduced to denote three types of imperfections containing sine, global, and local modes. At first, based on the von-Kármán geometric nonlinearity assumption, the forced vibration equation is set up. Then, the Galerkin method and multiple scale method are utilized to study subharmonic resonance behaviors. Finally, coupled effects of FG-CNTRCs, rotating motion, and geometric imperfections on subharmonic resonance responses are investigated. It is found that a specific range of the excitation amplitude and frequency motivates the subharmonic resonance behavior. The coupling of geometric imperfections and geometric nonlinearities generates the 1/2 resonance phenomena, and geometric nonlinearities result in the 1/3 resonance behavior. Both the imperfection mode and amplitude can affect the resonance response and resonance regions. Moreover, in contrast with the 1/3 subharmonic resonance, geometric imperfections produce greater influence on the 1/2 subharmonic resonance.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-09T08:00:00Z
      DOI: 10.1142/S0219455424502602
       
  • Train–Bridge Coupled Vibration of a Long-Span Steel Truss Suspension
           Bridge Under Complex Driving Conditions

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      Authors: Chuyi Xu, Hao Luo, Xianbei Gan, Mougang Liu, Hui Guo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To investigate the vibration characteristics of long-span suspension bridges under the impact of high-speed trains, a method for conducting a time–frequency domain analysis of the dynamic response of a coupled system is presented in this study. First, the finite element model of a suspension bridge is established to conduct modal analysis, and simulation results are compared with measured data to validate the correctness of the bridge model. Subsequently, a multi-body dynamics model of a high-speed train is developed. Then, two approaches, the dummy method and flexible-track method, are employed to create the train–bridge coupled system. Finally, the flexible-track method is used to perform time–frequency domain analysis of the system under complex operational conditions. The research revealed that large-span suspension bridges exhibit lower natural frequencies. The vertical bending vibrations of the main beam have the potential to significantly impact train operations. Under the combined impact of cable tension and wheel–rail forces, the vibration patterns of large-span suspension bridges become notably intricate. The number of trains and their loading configurations both exert influence over the dominant frequencies and amplitudes in the PSD of bridges. In the complex traffic of large-span suspension bridges, the rational arrangement of travel lanes can reduce the possibility of resonance in the bridge–train system.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-07T08:00:00Z
      DOI: 10.1142/S0219455425500063
       
  • Semi-Analytical Formula for Estimating Variance Response of Megawatt Wind
           Turbine Tower Under Parked Condition

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      Authors: Guoqing Huang, Tao Long, Min Liu, Ding Yuan, Liuliu Peng, Xing Tan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      As the supporting structure of the wind turbine, the tower is important for the safety of the wind turbine. The accurate estimation of tower response is critical for the wind turbine tower design. In the preliminary design, lots of calculations are necessary to determine design parameters. The traditional time domain calculation suffers its low efficiency and hinders the design progress. To overcome this difficulty, the frequency domain analysis should be developed, especially for the large wind turbine which may be significantly affected by the aerodynamic damping. In this study, a semi-analytical formula for the variance of the tower base bending moment is developed from the frequency domain analysis at parked condition. First, based on the quasi-steady theory and the three-component (mean, background and resonant components) method commonly used in the wind-resistant design of structure, the analytical formula of the variance for the tower base bending moment is presented considering the three components of the wind velocity. Second, the analytical formula is corrected based on the comparison with the calculation result by FAST. In the correction, the empirical aerodynamic damping is adopted. Finally, the applicability of the developed semi-analytical formula is verified by 5[math]MW, 10[math]MW and 15[math]MW wind turbines.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-07T08:00:00Z
      DOI: 10.1142/S021945542550018X
       
  • A Novel Analytical Method for Coupled In-Plane and Out-of-Plane Vibrations
           of Sandwich Plates with Arbitrary Boundary Conditions

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      Authors: Wanbo Li, Weifeng Liu, Ruihua Liang, Donghai Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Sandwich plates are popular in the research field of vibration damping and are widely used in numerous engineering domains. Sandwich plates have been studied extensively for their excellent performances by a large number of researchers. Due to the interaction between the out-of-plane and in-plane vibrations of the layers of sandwich plates, it is difficult to solve the displacements of each layer in all directions analytically. To deal with this problem conveniently and accurately, a novel analytical method is presented in this study for coupled out-of-plane and in-plane vibrations of sandwich plates, which can be applied to both free and forced vibrations of sandwich plates with arbitrary boundaries. In this method, the core plate is treated as a three-dimensional (3D) problem, and it is assumed that the displacement of the core plate varies linearly along the thickness. Based on the Kirchhoff hypothesis, the displacement solutions of the base and constrained plates of the sandwich plate in the [math], [math] and [math] directions are expressed as a superposition of one-dimensional (1D) and two-dimensional (2D) Fourier series, respectively. By comparison to the published analytical solutions and numerical results of the finite element method, the proposed method achieves excellent accuracy and reliability. In addition, the influence of out-of-plane and in-plane vibrations of sandwich plates on each other is studied, and the effects of geometrical and material parameters on the dynamic behaviors of a sandwich plate are investigated. The result shows that the out-of-plane vibration affects the in-plane vibration significantly, which means that the coupling effect of the out-of-plane and in-plane vibrations must be taken into account when analyzing in-plane vibration.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-07T08:00:00Z
      DOI: 10.1142/S0219455425500245
       
  • Assessment of Axisymmetric Dynamic Snap-Through and Thermally Induced
           Vibrations in FGM Cylindrical Shells Under Instantaneous Heating

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      Authors: A. Keibolahi, M. R. Eslami, Y. Kiani
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper addresses the investigation of axisymmetric thermally induced vibrations in Functionally Graded Material (FGM) cylindrical shells. It considers temperature-dependent (TD) properties and geometric non-linearity (the von Karman effect). The study systematically solves a transient heat conduction equation using finite differences method and the Crank–Nicolson method. During the heating stages, the evaluation of thermal forces and moments takes place. Equations of motion are derived through the application of Hamilton’s principle. Spatial dependencies are discretized using the generalized Ritz method, while temporal dependencies are approximated using the [math]-Newmark method with Newton–Raphson linearization. A comparative analysis validates the procedure’s efficiency and precision. Parametric studies explore the influence of parameters, including the temperature-dependency material properties, geometric nonlinearity, and shell’s power-law index, providing valuable insights into FGM shell behavior under thermal shock.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-07T08:00:00Z
      DOI: 10.1142/S0219455425500324
       
  • Structural Health Monitoring of Long-Span Continuous Girder Bridge: System
           Implementation and Data Analysis

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      Authors: Xiao-Mei Yang, Zhi-Wen Wang, Xu Zheng, Ze-Xin Guan, Dong-Hui Yang, Ting-Hua Yi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Long-span bridges are the key component of the human transportation system, linking communities over vast obstacles. To ensure the safe operation of long-span bridges, structural health monitoring (SHM) is perhaps the most effective solution. This study takes a 430[math]m four-span continuous girder bridge as an example and systematically presents an implementation example of the SHM system on the bridge regarding monitoring items, sensor placement, and sensor parameters. The monitoring data including operational load and bridge response are analyzed and the statistical rules of these monitoring data are presented. Besides, the modal parameters of the girder are tracked from long-term vibration monitoring data. Furthermore, the correlations between structural temperature and bridge response are analyzed, and the correlation formulas between bridge modal frequency, static responses, and structural temperature are finally given. The analysis results reveal significant seasonal variations in the responses of the continuously monitored girder bridge, offering valuable insights for data-driven assessment and early warning systems for bridges.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-05T08:00:00Z
      DOI: 10.1142/S0219455425500099
       
  • Vibration Control Effect Analysis of PTMD in Wind Turbine Tower Under
           Multi-Hazard Action of Earthquake and Vortex-Induced Wind

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      Authors: Shengqiang Zhao, Zheng Lu, Qiaoqiao Fan, Kaoshan Dai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Considering the importance of wind turbine tower, its vibration under multi-hazard action consisting of vortex-induced load and seismic load needs to be controlled, especially as the height of the wind turbine tower increases, it increases the risk of its higher-order vibration. To address this issue, theoretical equations for vortex-induced load based on the governing equation of particle damping system are put forward, the vibration control of a 1/20 scale wind turbine model is studied, and the experimental and numerical analyses are conducted. Many studies have shown that wind turbine tower equipped with tuned mass damper (TMD) can result in an RMS response reduction ratio ranging from 20% to 40%. Compared to TMD, particle tuned mass damper (PTMD) has better vibration control effect under single seismic load, and still achieves good vibration control ability with a maximum RMS (root–mean–square) reduction ratio of 35.55% under multi-hazard action. Furthermore, MPTMD (multiple particle tuned mass damper) is proposed for controlling higher-order vibration mode, achieving a maximum RMS reduction ratio of 65.93%. Combining the spectrum diagram result, the ability to control higher-order mode vibration of MPTMD is confirmed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-05T08:00:00Z
      DOI: 10.1142/S021945542550021X
       
  • Transient Response of Sandwich Plates with Corrugated Core Under
           Mechanical-Thermal Loads

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      Authors: Feng-Lian Li, Wen-Hao Yuan, Yu-Xin Hao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The nonlinear dynamic responses of the corrugated sandwich plate under mechanical-thermal loads are studied and analyzed. Based on hyperbolic parabola shear deformation plate theory (HPSDT), the partial differential equation of the sandwich plate with the corrugated core is established. Using the Galerkin truncation method, the nonlinear motion equation is derived. By the solution, the response of the corrugation plate with simply supported four edges at different temperatures is obtained and validated. Then the transient responses of the corrugated sandwich plate under different impact loads are analyzed, and the effects of the base materials, the corrugation types and the structural parameters of the corrugated plate on the transient responses are discussed in detail. The research provides a reference for improving the impact resistance of the sandwich plate in practical application.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-05T08:00:00Z
      DOI: 10.1142/S0219455425500221
       
  • Comparative Analysis of Structural Damage Identification Methods Based on
           Iterative Reweighted [math] Regularization and Three Optimization
           Functions

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      Authors: Wanli Yan, Yong Liu, Xinfeng Yin, Yang Liu, Yingfei Dong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Previous vibration-based damage detection studies mostly focus on developing a more sensitive optimization function to promote the effectiveness of damage identification. However, a few studies have conducted comparative analyses on the detection performance of different optimization functions. In the study, changes in the frequency and mode shape are applied as the inputs to different optimization functions for damage identification. Three optimization functions are established using the frequency residuals, the combinations of frequency and mode shape residuals, and the modal flexibility residuals, respectively. Considering the sparsity of damage element distribution, an iterative reweighted [math] [math] regularization is added as a norm penalty to the optimization function. A numerical model and an experimental example are applied to assess the performance of distinct optimization functions. The results show that the increase in modal data number cannot significantly improve the detection accuracy when the number meets the basic requirements for identifying damage. The detection error of the optimization function established by combining the frequency and mode shape residuals is 6.65% and 5.18% using the first four and fourteen-order noisy modal data, respectively. Furthermore, the optimization function constructed using the modal flexibility residuals requires more less modal data to identify damage than the other two functions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-05T08:00:00Z
      DOI: 10.1142/S0219455425500233
       
  • Gait Factor on the Energy Harvesting for a Simple Biped Robot

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      Authors: Fengxia Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To design walk-fast and energy-efficient robots, there has been lots of work in the last decade examining the locomotion dynamics of a passive biped. As the walking environment or system parameter changes, an energy use efficient robot may become inefficient. A possible approach to increase the energy efficiency is through the ability to harvest the energy used during the locomotion. The paper’s main goal is to investigate the relations between walking speed, the locomotion energy consumption of a passive biped, and the ability to retrieve the lost energy as locomotion energy efficiency varies. Piezoelectric bimorphs were attached to the feet of the biped to harvest energy via exploiting the acceleration excitations induced vibrations at the instant foot lift and heel strike. It is found that as a foot-to-hip mass ratio increases, the stable periodic-1 (P1) walking gait becomes slower and more energy costing. Also it means more available energy to harvest, although the retrieved energy is much smaller compared to the locomotive energy. Once the foot-to-hip mass ratio passes the periodic doubling (PD) point, P1 walking gaits will become limped P2 walking gaits, and the high energy cost situation alleviates, which also means less available energy to harvest. On the other hand, if the foot-to-hip mass ratio is fixed and the slope angle increases, the walking will experience sequences of PD bifurcations, and the walking gaits go through P1, P2, P4, P8, and chaotic walking. As the walking gaits change, the average walking efficiency, average locomotion energy consumption, and average harvested energy grow as the slope becomes deeper.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-05T08:00:00Z
      DOI: 10.1142/S0219455425500257
       
  • Three-Dimensional Dynamic Modelling and Analysis of a Dual-Cable Winding
           Hoisting System

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      Authors: Yandong Wang, Zemin Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, a three-dimensional dynamic model of a dual-cable winding hoisting system is presented to simulate and analyze its coupled vibrations. The equations of motion of this system are derived based on a substructure method and Lagrange’s equations of the first kind, in which the longitudinal–torsional coupled mechanical characteristics of the hoisting cables are considered. Longitudinal and transverse natural frequencies of the system are obtained and studied, and its dynamic responses due to some assumed displacement excitations are calculated. Numerical results agree well with those from ADAMS simulation, and the results have shown that longitudinal and transverse resonances are inevitable, but the transverse resonance has little effect on the conveyance; Slow longitudinal excitations should be avoided, thus avoiding the first-order longitudinal resonance since the system longitudinal vibration is dominated by its first-order mode; the torque in the hoisting cable is mainly induced by its tension under longitudinal–torsional coupled mechanical characteristics of the cable, and a torque release device is suggested to protect the hoisting cable from torsion failure; Torsional and transverse vibrations of the conveyance are been well restricted by the guiding cables even when the guiding cable pre-tension is zero. The results of this paper can be used to improve the parameter design of the ultra-deep shaft hoisting systems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-02T08:00:00Z
      DOI: 10.1142/S0219455424501785
       
  • Non-Linear Stability of Aluminum Alloy Single-Layer Reticulated Shells
           Considering Stressed-Skin Effect

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      Authors: Xiaonong Guo, Zilin Tang, Xuanyu Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The stressed-skin effect refers to the enhancement of skin stiffness on structural stiffness and the ultimate load. Accurately quantifying the magnitude of the stressed-skin effect is of great significance for the safety and economic benefits of structures. In existing research, the skin panels are usually modeled by shell elements rigidly connected to the members, which may have lower computational efficiency and are not consistent with actual construction practices. For the triangular skin panels in aluminum alloy single-layer spherical reticulated shells, this paper proposed a simplified calculation model based on multiple non-linear springs. This model can greatly reduce the number of elements and its reliability has been successfully validated. Through parametric analysis, it was observed that the skin stiffness is primarily determined by the thickness of the skin panels and the connection stiffness between the skin panels and the members. The simplified model was applied to the models of aluminum alloy single-layer spherical reticulated shells to explore the effects of skin stiffness and initial geometric imperfection on the ultimate load of the shells. The results show that considering skin stiffness can increase the ultimate load by 10–20%, while the adverse effects of initial geometric imperfection can be weakened. Based on extensive numerical results, the formula for the ultimate load of the aluminum alloy single-layer spherical reticulated shells was modified to consider the stressed-skin effect.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-02T08:00:00Z
      DOI: 10.1142/S0219455425500130
       
  • A Novel Frictional Sliding Shear Key for the Transverse Seismic Mitigation
           of Girder Bridges

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      Authors: Chenxi Xing, Ben Sha, Hao Wang, Yifeng Wu, Aiqun Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The concrete shear keys (CSK) are the conventional component in the girder bridges to restrain the seismic-induced excessive displacement in the transverse direction. However, the failure of the CSKs is often observed in strong earthquake events, which indicates the inadaptability of the CSKs in such extreme circumstances. This study proposes a novel frictional sliding shear key (FSSK) to improve the seismic performance of girder bridge especially under the earthquakes with high intensities. The configuration and the working mechanism are first introduced to derive the governing equations and the hysteretic models. A design method is proposed on the premise of the safety of the pier columns to determine the parameters of the FSSK. The mitigation effectiveness of the FSSK is investigated through a case study of a typical isolated bridge subjected to a suit of 80 ground motion records with 12 levels of seismic intensities. Results demonstrate that the lateral force and the energy-dissipating ability of the FSSK both increase dramatically with the increase of its lateral deformation, which implies the FSSK could play a more significant role under strong earthquakes. The numerical results of the case study denote that the FSSK can prominently reduce the bearing deformation of the bridge model under strong earthquakes, while the seismic responses of the pier could be enlarged. Besides, the combination of the FSSK and the CSK could further decrease the bearing deformation and only slightly increase the pier responses at high seismic intensities. The findings of this study are aimed at improving the transverse performance of the girder bridges under strong earthquake.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-03-02T08:00:00Z
      DOI: 10.1142/S0219455425500166
       
  • Study on Dynamic Characteristics of Vibration System with Two Degrees of
           Freedom and Multiple Rigid Constraints

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      Authors: Ling-Yun Zhang, Zhong Liu, Shi-Jun Wang, Zhong-Gang Xiong, Xing-Guo Han, Yong Lv
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A dynamic model of a vibration system with two degrees of freedom and multiple rigid constraints is constructed, the dynamics constraints of the segmented smooth vibration system under the multi-body impact coupling condition are given. Based on the cell mapping principle, a two-parameter co-simulation is carried out with two important parameters of excitation frequency and constraint gap as control variables. The model types and distribution rules of the periodic motion of the system response on the [math]-whole two-parameter plane are obtained. The correlation between the dynamic response of the system and the model parameters is analyzed, and the evolution and bifurcation characteristics of fundamental periodic vibrations in the low-frequency small-gap parameter domain of the two-degree-of-freedom multi-rigid constrained vibration system are discussed. The diversity and regularity of subharmonic shock vibrations in the translational domain of the lingual domain are found.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-29T08:00:00Z
      DOI: 10.1142/S0219455425500142
       
  • Multi-Performance Economical Optimization of Base Isolation System with
           Tuned Inerter Negative Stiffness Damper Subjected to Non-Stationary
           Seismic Excitation

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      Authors: Wenfu He, Yuxiang Zhou, Zhihao Wang, Hao Xu, Xiangliang Ning
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Base isolation proves to be an effective vibration control strategy for buildings. However, the base-isolation floor (BIF) may undergo substantial displacements. To improve the seismic performance of base-isolation system, this paper proposes a multi-performance economical optimization procedure (MPEOP) for exploring the optimal parameters of base isolation system with tuned inerter negative stiffness damper (BIS-TINSD) subjected to non-stationary seismic excitation. The simplified analysis model for BIS-TINSD is developed, followed by the formulation of the state-space representation. The non-stationary seismic excitation is represented as a stationary Gaussian process with a time-modulating function based on the Clough–Penzien spectrum, and combining the equations of motion with seismic excitation results in the augmented state-space representation of structure-damper-excitation, followed by the formulation of differential Lyapunov equation. The multi-objective performance economical index is proposed, in which the performance optimization objective is defined as a weighted combination of base isolation floor displacement and superstructure acceleration, and the economic optimization objective is set as the support stiffness. The Pareto optimal fronts (POF) are adopted to deal with optimal objectives. The examination of optimal design parameters is extended under real earthquake records. The results demonstrate the effectiveness of the MPEOP, and indicate the advantages of the BIS-TINSD compared with the inerter amplify damper (IAD) and negative stiffness inerter damper (NSID).
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-29T08:00:00Z
      DOI: 10.1142/S0219455425500154
       
  • Nonlinear Dynamic Analysis of FG Fluid Conveying Micropipes with Initial
           Imperfections

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      Authors: Qiliang Wu, Nianwen Chen, Minghui Yao, Yan Niu, Cong Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the nonlinear dynamics of FG-FCMPs with initial imperfections. Based on the MCST, the nonlinear equations of motion and the corresponding boundary conditions are established by applying Hamilton’s principle, the Euler–Bernoulli beam theory, and von-Kármán geometric nonlinearity. To describe the initial geometric imperfection of the FG-FCMP, the first-order vibrational mode is employed. Subsequently, in cases of primary parametric resonance, 1:2 subharmonic resonance for the first-order mode, as well as primary resonance for the second-order mode, Galerkin’s method, and the multiple scale method are utilized to analyze the amplitude–frequency responses of the imperfect FG-FCMP. The numerical simulations test the influence of flow velocity, micro-scale parameter, geometrical imperfections, and external loads on the nonlinear characteristics of a coupled system with two DOFs. It is found that, as the increase of flow velocity, micro-scale effect, and external load, the amplitude of the first two modes can be increased. The hardening characteristics are converted into the softening characteristics due to the imperfect effect. Furthermore, numerical results provide a more comprehensive understanding of the nonlinear dynamics of FCMPs for both periodic and chaotic motions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-29T08:00:00Z
      DOI: 10.1142/S0219455425500178
       
  • Application of the Elastic Curve Equation for the Verification of
           Structures Assimilable to Continuous Beams

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      Authors: Faustino N. Gimena, Pedro Gonzaga, Mikel Goñi, José Vicente Valdenebro, María Senosiain
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper analyzes the beam under isolated and uniform loads, extending this calculation towards the structural type of the continuous beam, by means of a single expression of the elastic curve. A general expression of the bending is proposed, deduced by integrating the different differential equations of the elastica, associated to each section between discontinuities produced by the loads. In this paper, support reactions are incorporated into the load system. Therefore, the continuous beam is understood as a bar made up of sections aligned between discontinuities. With this, the isostatic beam, the hyperstatic beam and the continuous beam can be treated by means of the same integrated expression of the displacement, also called the Macaulay method. Equivalent notations are provided to the expression of bending for the cases of traction–compression and torsion, obtained through the same reasoning and sequence of operations. The formulation of elastic type and the associated operations shown allow us to cover the analysis of the generic structural form, which we can define as the beam of any number of spans, or continuous beam of [math] spans. The load system is also generalized, being able to contemplate loads of a different nature and form of distribution, both static and mobile. The examples that have been developed always provide analytical results of solicitation and deformation. They intend to explain the systematic path followed from the approach of the structural problem to its mathematical modelling, and the resolution procedure developed to obtain useful values for the structural verification. In these examples, an increasing degree of complexity and generalization has been followed. The expressions obtained are validated by comparing them with those that are usual in the structural literature for the same or similar problems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-29T08:00:00Z
      DOI: 10.1142/S0219455425500191
       
  • Directly Self-Starting Second-Order Explicit Integration Methods with
           Dissipation Control and Adjustable Bifurcation Points for Second-Order
           Initial Value Problems

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      Authors: Jinze Li, Naigang Cui, Hua Li, Yiwei Lian, Kaiping Yu, Rui Zhao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper proposes a directly self-starting second-order [math]-sub-step explicit method, within which the three novel members are developed and analyzed for demonstration. The novel explicit schemes can output second-order accelerations for general structures, which cannot be achieved for the directly self-starting single- and two-sub-step algorithms. Each explicit algorithm achieves controllable algorithmic dissipation and adjustable bifurcation points. As a result, the novel explicit algorithms impose two algorithmic parameters, [math] and [math], to control numerical dissipation and bifurcation point, respectively. The parameter [math], denoting the spectral radius at the bifurcation point, controls numerical dissipation, whereas the parameter [math], denoting the bifurcation point, adjusts the amount of dissipation imposed in the low-frequency range. This paper provides users with two recommended selections of [math]. Apart from these desirable features, each novel explicit algorithm attains the maximum stability bound, [math] where [math] denotes the number of sub-steps. The four- and five-sub-step algorithms perform optimization to reduce numerical low-frequency dissipation. As the number of sub-steps increases, the novel explicit algorithms can have better numerical characteristics without an increase in the computational effort. Numerical examples are simulated to validate the performance and superiority of the novel explicit algorithms.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-28T08:00:00Z
      DOI: 10.1142/S0219455424502742
       
  • Nonlinear Vibration and Stiffness Characteristics Analysis of Maglev Train
           Based on Cubic Displacement Control

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      Authors: Shuaikang Cao, Canchang Liu, Can Wang, Liang Sun, Shuai Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A control strategy combining cubic displacement feedback nonlinear control and proportional-differential (PD) linear control is used to control the vibration performance of the maglev system. The maglev system is divided into positive stiffness maglev system, quasi-zero stiffness maglev system and negative stiffness maglev system according to the linear stiffness value of maglev system. Firstly, an improved multi-scale method is used to analyze the vibration characteristics of suspension in the positive stiffness state of the maglev system. Secondly, the influence of control parameters on train vibration amplitude and vibration center displacement under quasi-zero stiffness is studied. Finally, the vibration characteristics of the train when the maglev system is in negative stiffness are analyzed by numerical simulation. The maglev system exhibits the worst vibration performance under negative stiffness compared with positive stiffness and quasi-zero stiffness. The suspension frame is easy to enter the chaotic motion state, and its vibration center is easy to deviate from the equilibrium position and produce large displacement when the maglev system is in the negative stiffness state. The control results show that the control strategy combining the cubic displacement feedback nonlinear control with the PD linear control can make the maglev system exhibit better vibration characteristics under positive and quasi-zero stiffness.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-28T08:00:00Z
      DOI: 10.1142/S0219455424502791
       
  • Study on the Fundamental Frequency and Dynamic Mode of Traveling Wave
           Vibration of Rotating PJCS

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      Authors: Y. X. Hao, L. Sun, W. Zhang, H. Li, W. Li, S. W. Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The vibrations of rotating joined conical–conical shells with classical supported conditions have been studied extensively. As a matter of fact, in some cases, these classical boundary conditions cannot exactly model actual situations. Moreover, theoretical frameworks on them are still limited. This research aims to investigate the fundamental frequencies and dynamic mode shapes of the traveling wave of the rotating porous metal material joined conical–conical thin shells (PJCS) with elastic supports. By utilizing artificial spring technology, arbitrary elastic supported boundary conditions and classical boundary conditions are achieved efficiently. A new dynamic model has been formulated with the help of the first-order shear deformation theory (FSDT) and Hamilton’s principle. By employing the generalized differential quadrature (GDQ) method along with stress boundary conditions and generalized eigenvalues, various factors such as porosity, semi-vertex angles and stiffness are analyzed for their impact on the fundamental frequencies of forward wave (FW), backward wave (BW) and mode shapes. The presented results are validated through the convergence and comparison studies from literatures. The interesting and novel results indicate that the in-plane displacement constraints have the most significant impact on the critical speed, while the lateral displacement constraint has the least effect. The vibrations are more easily excited for the part with a larger half vertex angle. Rotating PJCS with Type 1 has the biggest critical rotating speed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-28T08:00:00Z
      DOI: 10.1142/S0219455424502808
       
  • Model Reduction of a Continuous System with Friction-Induced Vibration
           Considering Separation and Re-Contact

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      Authors: Ningyu Liu, Huajiang Ouyang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The friction-induced vibration of a continuous system consisting of two flexible beams in sliding contact to represent a brake system is studied in this paper. Besides the motion of relative sliding when the two beams are in contact, the separation of beams may also happen in the system dynamics. The complex eigenvalue analysis for the stability of the steady sliding state and the transient dynamic analysis for the characteristics (intensity and periodicity) of the steady-state responses of the system are carried out. Moreover, the results obtained using different numbers of beam modes are acquired and compared. It is found that only a few low-order beam modes need to be incorporated to get accurate results of the stability of the steady sliding state and the steady-state responses of the continuous frictional system, which therefore theoretically justify the omission of high-order modes of continuous structures when investigating the friction-induced vibration of continuous systems and thereby greatly reduce the computational cost. Additionally, the inclusion of the separation and re-contact behavior has a significant effect on the number of required modes for accurate steady-state responses compared with that when no separation is considered, which also verifies the important role of the separation and re-contact behavior in the system dynamics. Besides, a reduced dynamic model that can produce identical dynamic behaviors to those of the continuous frictional system is constructed, with the structural parameters of the reduced model derived from the several key low-order modes of beams.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-23T08:00:00Z
      DOI: 10.1142/S021945542550004X
       
  • Crashworthiness Analysis and Optimization of Thin-Walled Structures Based
           on the TSSA-LSSVM Surrogate Model

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      Authors: Weiwei Wang, Yi He, Tianci Zhang, Wenhao Zhang, Fei Ju, Xiaomei Xu, Haris Waqar Ahmed
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Thin-Walled Structures (TWS) play a crucial role in enhancing both the collision safety and lightweight characteristics of vehicles. Structural design and optimization have demonstrated significant potential in improving their crashworthiness and overall weight reduction. Several interconnected factors, including the cross-sectional shape and parameters of distinctive structural characteristics (known as induction grooves), impact the TWS’ resistance to collisions. Another critical aspect in the optimization of TWS design is striking the delicate balance between the surrogate model’s effectiveness and precision. Taking all these factors into account, this paper conducts an in-depth investigation into the cross-sectional shape, grooves, and other geometric attributes of various TWSs through a comparative analysis. It reveals that the thin-walled structure with a Double-Ribbed Rectangle cross-section (DR-TWS) proves to be the optimal choice, particularly in low-speed axial impact scenarios. Furthermore, we present an enhanced Least Squares Support Vector Machine (LSSVM) method, augmented with an adaptive [math]-distribution Sparrow Search Algorithm (TSSA), referred to as the TSSA-LSSVM surrogate model. The optimized design of the DR-TWS is realized through the integration of the TSSA-LSSVM surrogate model with the adaptive hybrid multi-objective particle swarm optimization (AHMOPSO) algorithm. This paper not only provides substantial theoretical support but also offers valuable guidelines for the application of TWSs in the automotive industry.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-22T08:00:00Z
      DOI: 10.1142/S0219455425500038
       
  • An Improved First-Order Shear Deformation Theory for Wave Propagation
           Analysis in FG-CNTRC Beams Resting on a Viscoelastic Substrate

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      Authors: Qais Gawah, Fouad Bourada, Mohammed A. Al-Osta, Saeed I. Tahir, Abdelouahed Tounsi, Murat Yaylacı
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper aims to analyze the wave propagation in functionally graded carbon nanotube-reinforced composite (FG-CNTRC) beams placed on a viscoelastic foundation utilizing an improved first-order shear deformation theory (FSDT). The material properties are derived from the mixture rule. Four carbon nanotube distribution patterns are considered in the analysis. The extended Hamilton’s Principle is utilized to derive the governing wave equations for the CNTRC beam. A comparison between the present theory results and those in the literature is conducted for validation. The wave dispersion investigation is mainly based on the phase and group velocities. The results illustrate the wave propagation responses for the different CNT configurations. In addition, the influence of the CNTs volume fraction, foundation stiffness parameters, and damping coefficient on the wave characteristics is examined.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-22T08:00:00Z
      DOI: 10.1142/S0219455425500105
       
  • Dynamic Response of Buried Natural Gas Pipelines under Horizontal
           Directional Drilling Loads

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      Authors: Kai Zhang, Liqiong Chen, Ting He, Duo Xu, Weihe Huang, Song Yang, Zhiqiang Zeng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Due to the unobservable nature of underground construction and the destructive nature of horizontal directional drilling rigs with high power, this type of construction has become one of the most important causes of failure of long-distance natural gas pipelines. In recent years, horizontal directional drilling construction has caused pipeline accidents frequently. Once the accident occurs, the normal operation of natural gas pipelines cannot be ensured. Therefore, studying the damage mechanism of buried natural gas pipelines under horizontal directional drilling loads is important for the safe operation of pipelines. This paper combines the construction characteristics of horizontal directional drilling and the actual situation of natural gas pipelines to explore the relationship between horizontal directional drilling and pipelines. The force situation of pipelines after contacting directional drilling bits is analyzed by the drill bit-soil-pipe finite element model created in the ABAQUS software. The Johnson–Cook ductile damage model was utilized to determine the pipe’s damage condition. The sensitivity analysis results show that he order of the impact of key parameters on the dynamic response of the pipe is bit thrust [math] wall thickness [math] bit diameter [math] pipe diameter [math] bit speed [math] number of bit teeth [math] pipe operating pressure. Therefore, priority should be given to controlling the size of the drilling thrust and the speed of the drill bit to reduce the damage to pipelines by horizontal directional drilling construction. In addition, appropriately reducing the pipeline operating pressure can also reduce the risk of the pipeline being damaged by horizontal directional drilling construction.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-22T08:00:00Z
      DOI: 10.1142/S0219455425500117
       
  • Dynamic Response Recovery of Damaged Structures Using Residual Learning
           Enhanced Fully Convolutional Network

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      Authors: Qizhi Tang, Jingzhou Xin, Yan Jiang, Hong Zhang, Jianting Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Structural dynamic response corrupts frequently due to the sensor malfunction. The loss of dynamic response will hinder the structural condition assessment. In recent years, significant efforts have been devoted to recovering the dynamic response during the linear elastic stage of the structure. However, relevant researches on the response recovery of damaged structures are rarely reported due to its strong nonlinearity. With the growing significance of post-disaster structural maintenance, it is critical to develop effective methods for recovering missing data in damaged structures. To this end, this paper proposes a dynamic response recovery method for damaged structures using residual learning enhanced fully convolutional networks (FCN), which can provide a baseline for the recovery of monitoring data in operational civil infrastructure. Specifically, a FCN incorporating residual learning and skip connections is designed to capture high-dimensional nonlinear relationships between input and output channels, thereby achieving the data recovery for any concerned channel. Then, a time–frequency domain evaluation mode is constructed, in which L2 norm is used to measure the difference of recovery results in the time domain, while instantaneous frequency is employed to evaluate the integrity of the spectral information of recovery results. Finally, a destruction test of an experimental arch was conducted, and the acceleration data under different damaged state were collected to investigate the feasibility of the proposed method. Besides, the recovery effects concerning input channel location and quantity, multi-channel response and cross-state recovery are examined. The results show that even in a severely damaged state, the proposed method effectively recovers the missing data. In addition, improving the correlation between input and output channels and increasing the number of input channels can further enhance the recovery accuracy.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-21T08:00:00Z
      DOI: 10.1142/S0219455425500087
       
  • Multi-Mode Vibration Control of Super-Long Stay Cables with Negative
           Stiffness and Stockbridge Dampers

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      Authors: Zhihao Wang, Yang Liu, Hui Gao, Zhipeng Cheng, Hao Wang, Yanwei Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Installing mechanical dampers near the cable anchorage is a commonly used measure for suppressing rain-wind-induced vibrations (RWIVs) of stay cables. However, the high-mode vortex-induced vibrations (VIVs) are still observed on super-long stay cables installed with dampers. To this end, the study presents the combination of a negative stiffness damper (NSD) and Stockbridge dampers (SDs) to simultaneously suppress cable RWIVs and VIVs. In the proposed cable–NSD–SDs system, the NSD is installed near the cable anchorage to suppress cable RWIVs, and the SDs are installed at a higher location to suppress cable VIVs. First, the generalized characteristic equation of the cable–NSD–SDs system is derived for computing the coupled damping effect. Subsequently, a novel design method of an NSD and two SDs for mitigating cable multi-mode vibrations is proposed, and its effectiveness is numerically verified on an ultra-long stay cable of the Sutong Bridge. Finally, the control performance of an NSD and two SDs for the cable under white noise and harmonic excitations is emphatically evaluated and compared. Results indicate that the NSD–SDs system is quite effective for mitigating high-mode vibrations of super-long stay cables. Compared with the cable–NSD system, the cable acceleration response of the cable–NSD–SDs system is reduced by over 35%.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-19T08:00:00Z
      DOI: 10.1142/S0219455425500014
       
  • Influence of Seismic Wave Incidence Angle on Dynamic Responses
           and Vibration Control of Adjacent Liquid Storage Tanks

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      Authors: Wei Jing, Shihao Wang, Jian Shen, Shushuang Song
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Liquid storage tanks are often arranged in rows with small spacing in practical applications, which may cause mutual influence under earthquake action and even aggravate the seismic damage of liquid storage tanks. Adding the vibration barrier (ViBa) into the foundation between the adjacent liquid storage tanks forms a new type of seismic control method. Considering important factors such as liquid–solid–soil coupling, liquid sloshing behavior, and structure–soil–structure interaction (SSSI), a refined 3D numerical calculation model of the adjacent liquid storage tanks with three ViBas is established by ADINA. The influence of seismic wave incidence angle on the seismic responses of the liquid storage tanks and the control effect of ViBa are studied, and the parameter influence analysis is carried out. The results show that the ViBa significantly control the seismic responses and liquid sloshing wave height of the adjacent liquid storage tanks, and the damping ratio of the liquid sloshing wave height is between 30% and 40%. When the seismic incidence angle is between 30[math] and 60[math], the dynamic responses of the liquid storage tank is larger. With the increase of the seismic incidence angle, the control effect of the ViBa on the effective stress, hoop stress, axial compressive stress, and liquid pressure first increases and then decreases. When the liquid storage tank is close to full state, the control effect is most significant at an incidence angle of 60[math], and the control effect of the ViBa on the liquid storage tank with medium height-diameter ratio is the best.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502547
       
  • A Generalized Dynamic Analysis Method for the Linear Structural System
           with Viscoelastic Elements

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      Authors: Pan-Pan Gai, Zhao-Dong Xu, Qin-Sheng Bi, Zi-Cong Xie, Jun Dai, Wen-An Jiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The high-damping viscoelastic (VE) materials are widely used to reduce unwanted vibrations in civil structures. However, the significant frequency and temperature dependences from high-damping VE materials cause a challenge in efficiently analyzing the structural dynamic behaviors. The aim of this study is to propose a generalized dynamic analysis method for the linear structural system with VE elements. The implementation steps and advantages of the dynamic analysis method are presented. In this method, the frequency-dependent matrices and non-proportional damping induced by VE elements are fully considered in modal coordinates, and then the state-space representation converted from the modal-based transfer function is adopted to implement the time-domain simulation. Any popular VE constitutive models which accurately describe frequency-dependent matrices can be applied to the method. The number of the state-space representation can be adjusted according to the interested frequency range. Numerical applications performed on a viscoelastically damped structure, a VE base-isolated structure, and a structure with a VE tuned mass damper (TMD) demonstrate the numerical accuracy, efficiency, and generality of the proposed dynamic analysis method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502626
       
  • Dynamic “Disengagement-Closure” Contact Characteristics of
           Track–Bridge Interface Caused by High-Speed Train Under Side Pier
           Settlement

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      Authors: Yulin Feng, Shuai He, Binbin He, Lizhong Jiang, Wangbao Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A nonlinear dynamic model of a train–bridge-longitudinal track coupling system considering the dynamic contact of the bridge–track interface (BTI) is established. Based on the previously established BTI contact characterization model and train–bridge coupling joint simulation model, the proposed model is verified from both static and dynamic perspectives. Accordingly, the dynamic displacement variation law of the bridge–track structure before, during and after the train passing through the side pier settlement area, the additional stress dynamic variation law and the interlayer connection dynamic variation law are analyzed. Moreover, the amplification effect of the wheel repeated “beating effect” on the dynamic contact force of “disengagement-closure-redisengagement” of the BTI void area is also analyzed. The results show that the accuracy of the proposed model can be verified from both static and dynamic perspectives. During the train passes through the settlement area, the dynamic deformation of track is the largest. Before and after the train passes through the settlement area, the dynamic deformation of track is basically the same. During the train passes through the settlement area, the BTI completes a dynamic contact process of “disengagement-closure-redisengagement”. The static effect of the side pier settlement on the dynamic bonding force of sliding layer is much larger than the dynamic effect of the train load. The dynamic effect of the train load is much larger than the static effect of the side pier settlement on the dynamic bonding force of the CA mortar and fasteners. The side pier settlement has a dynamic amplification effect on the train wheelset. Along the mileage direction, there are interface voids and contact areas in the dynamic bonding force of sliding layer and CA mortar, while there are no voids and contact areas in the dynamic bonding force of fasteners.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502651
       
  • Vibration Performance Evaluation of Cold-Formed Steel and Plywood
           Composite Floors

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      Authors: Suleiman A. Al-Hunaity, Harry Far
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, experimental natural frequencies and mid-span deflections were used to assess the tested composite floors against vibration serviceability limit states adopted by different standards such as AS3623. It was found that existing design criteria have predicted inconsistent results. Further, the finite element (FE) model was created, updated, and validated against the experimental modal parameters. The validated numerical model examined how various design parameters, such as material properties, cross-section geometry, and achieved a degree of composite action, have influenced the vibration properties such as natural frequencies and mode shapes. It was shown that as the added mass became more dominant than the stiffness enhancement, the fundamental natural frequency of the floor system dropped. This was evident from the results of the plywood slab thickness and the added permanent load parameters. On the other hand, the fundamental natural frequency increased with thicker and deeper joist sections since they made the floor system stiffer.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502699
       
  • Global–Local Damage Diagnostic Approach for Large Civil Structures
           with Very Limited Sensors

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      Authors: K. Lakshmi, Prateek Arora, A. Rama Mohan Rao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      It is important but still challenging to detect structural damage with limited instrumentation in the spatially large civil infrastructure. In this paper, a damage detection algorithm is proposed employing a global–local approach with limited sensors for detecting structural damage of spatially large civil engineering structures. The proposed algorithm is based on measuring frequency response functions (FRFs) at convenient yet selective locations on the structure with very limited sensors to localize the region of damage in the structure using the proposed global diagnostic approach. Once the local region of damage is established, local diagnostics are performed in the isolated small region of the structure using high fidelity sensing, still, a limited number of sensors in the small localized region (segment) of the structure, to precisely locate the damage. The principal component analysis combined with fractal dimension theory is employed for local diagnostics. Numerical studies have been conducted on a 6[math]m simply supported beam and a 30-storey framed structure idealized as a shear building. Experimental verification of the proposed global–local damage diagnostic approach is also carried out. Studies presented in this paper indicate that the global–local approach for damage diagnosis of spatially large structures is very promising for precisely locating the damage with very limited sensors.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502705
       
  • Subsonic Aeroelastic Stability Analysis and Vibration Control of a Plate
           by Using Nonlinear Energy Sink

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      Authors: Yu Qiao, Guo Yao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Vibration suppression and stability control are classic issues in the field of vibration and control. The nonlinear energy sink (NES) is an effective approach for vibration reduction proposed in recent years. It has the advantages of wide frequency vibration isolation properties and without inputting excessive energy. This paper focuses on the stability and passive vibration control of a plate in subsonic airflow by applying the NES. Two kinds of NESs with linear stiffness and with cubic stiffness are proposed and their vibration control performances are compared. The kinetic equations of the plate with NES are established by using the extended Hamilton principle and analyzed by the incremental harmonic balance (IHB) method. The advantages of the hybrid stiffness NES are demonstrated by comparing with the cubic nonlinear stiffness NES. From the results, the vibration suppression effect of the hybrid stiffness NES is more significant than the purely cubic one. However, the effective vibration reduction range of the cubic stiffness NES is wider than the hybrid one. The optimal design parameters of the NES and the effect of the installation position are also discussed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502730
       
  • The Influences of the Offshore Ground Motion and Site Factors on the
           Seismic Response of Immersed Tunnels

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      Authors: Bowei Wang, Sicong Hu, Guquan Song, Baokui Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Because the seabed is covered with deep slit soil and seawater layer, the characteristics between offshore and onshore ground motions are significantly different. Besides, compared with sea-crossing bridges and other marine structures, the seismic response of immersed tunnels buried under seabed can be influenced by the site condition more significantly. Therefore, it is necessary to study the effects of seawater depth, site condition and offshore ground motion on the seismic response of immersed tunnels. Firstly, offshore strong motion records from the K-NET are grouped with different epicentral distances, magnitudes, and stations, and the response spectra of offshore ground motions in different groups are compared. Then, a numerical simulation model with the water layer, offshore soil layer and immersed tube tunnel coupling is established. The seismic responses of the tunnel and the seabed site are compared by inputting offshore and onshore ground motions respectively. Finally, the effects of seawater depth, incidence angle, slit soft soil layer and buried depth on the seismic response of tunnel and local seabed site are systematically studied by inputting P wave and SV wave pulses respectively. The results show that the silt soft soil layer will make the horizontal seismic response of the immersed tunnel more serious under SV wave incidence. The vertical seismic responses of the immersed tunnel and seabed are suppressed by the seawater layer under P wave incidence, and the response will decrease with seawater depth increasing. Besides, the effect of the buried depth and incidence angle on the seismic response of the immersed tunnel is limited.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502766
       
  • Interval Uncertainty Identification and Application of Strain Modes in
           Bridge Structures Based on Monitoring Big Data

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      Authors: Ruiyang Pan, Danhui Dan, Xingfei Yan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In order to solve the problem of strain modal identification under strain monitoring signals with poor vibration modal information, this paper proposes a strain mode identification method with statistical stability significance. This method removes noise, vehicle-induced effects, and temperature effects from the original dynamic strain signal, retaining only vibration-related components, and obtaining a statistically stable high quality bridge strain power spectrum, thereby identifying high quality strain mode parameters. Furthermore, in order to verify the confidence level of the strain modes obtained by this method, this paper adopts the interval estimation method to estimate the power spectrum, natural frequency, damping ratio, and modal shape after statistical processing. The credibility of strain modes has been estimated by interval estimation. The confidence interval of 95% confidence for each modal parameter is obtained, achieving the confidence-level evaluation of corresponding variable modal parameter identification. In response to practical engineering problems, this paper evaluates the actual bridge data of Tongji Road Bridge in Shanghai, and explains the abnormal phenomena that occurred in the data evaluation based on the measured diseases, verifying the practicality of this method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-14T08:00:00Z
      DOI: 10.1142/S0219455424502778
       
  • Analysis of Torsional Vibration in a Fractured Poroelastic Half-Space
           Coated with Metal Foam and Sliding Interfaces

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      Authors: Dipendu Pramanik, Santanu Manna
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Metal foams are highly useful in industries because of their lightweight, energy and vibration absorption properties. This study investigated the propagation of torsional waves in an elastic layer over a fluid-saturated fractured poroelastic half-space with a metal foam coated layer. It is assumed that the interfaces are in sliding contact with two different sliding parameters. The coated layer is closed-cell aluminium foam. We use the separation variable technique and the Bessel function to solve the equation of motion in different layers. The displacement components are written in terms of the second kind Whittaker functions. Using an asymptotic formulation of the Whittaker function and appropriate boundary conditions, the dispersion equation is derived in terms of the determinant. The control of the vibration due to the metal foam-coated layer is one of the important goals of this study. Also, numerical and graphical analyses have been done with the help of Mathematica software to see the effect of different parameters on torsional wave propagation. It is found that the presence of coated metal foam layer decreases the phase velocity of the torsional wave propagation. The work may be helpful in the seismology, automobile, and aerospace industries.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424400194
       
  • Analysis of Key Influencing Factors of Track Dynamic Irregularity Induced
           by Earthquakes in the High-Speed Railway Track–Bridge System

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      Authors: Wangbao Zhou, Jun Xiao, Shaohui Liu, Lizhong Jiang, Jian Yu, Lingzhi Zu, Lingxu Wu, Zhenbin Ren
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Stiffness degradation of track–bridge systems under earthquake excitations can lead to track dynamic irregularity, impacting the safety of train operations post-earthquake. In this paper, the nonlinear time-history analysis of CRTS II track–bridge system model established by ANSYS finite element analysis software is carried out under the action of transverse random earthquake. The train–track–bridge system model considering the stiffness degradation caused by earthquake is established by MATLAB, and the earthquake-induced track dynamic irregularity sample library is constructed. The probability distribution mode of the power spectral density sample of the earthquake-induced track dynamic irregularity is explored and the calculation method based on the probability guarantee rate is proposed. The influence of structural damping ratio, train running speed and train type on the power spectral density curve of the earthquake-induced track dynamic irregularity is analyzed. The results show that the power spectrum samples of track dynamic irregularity conform to the hypothesis test of a normal distribution. The power spectral density of earthquake-induced dynamic irregularity primarily consists of medium and low-frequency components. When the structural damping ratio increases from 0.03 to 0.04, 0.04 to 0.05, 0.05 to 0.06, and 0.06 to 0.07, the variation gradients are 0.1701, 0.1240, 0.1034 and 0.0999, respectively, which indicates that the structural damping ratio has a significant effect on the power spectral density of earthquake-induced irregularity, and the impacts of train speed and train type on the power spectral density of near-fault earthquake-induced irregularity are minimal.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502468
       
  • Dynamic Receptance Analysis Combined with Hybrid FE-SEA Method to Predict
           

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      Authors: Xihao Jiang, Xiaozhen Li, Yao Yuan, Haoqing Li, Di Wu, Lin Liang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, dynamic receptance analysis (DRA) is proposed and combined with hybrid finite element (FE)-statistical energy analysis (SEA) method to accurately predict structural noise from long-span cable-stayed bridge (LSCB) with steel box composite girder (SBCG) in urban rail transit (URT). To begin with, a vertical vehicle–track coupling model in frequency domain is established based on DRA, in which the rail is represented by an infinite Timoshenko beam supported by a series of fasteners that are regarded as springs with complex stiffness. The floating slab is regarded as the Euler beam with both ends free supported by steel springs. Using this model, the spectrums of the wheel–rail force and the forces transferred to the bridge can be efficiently obtained by taking rail roughness as the excitation. Due to the low modal density of the concrete deck, the hybrid FE-SEA method is introduced to establish the noise prediction model, in which the discontinuity caused by using distinct models for different frequency bands is avoided. Then the on-site noise tests of a LSCB with SBCG in URT are carried out to verify of the proposed method. Finally, based on the prediction method, the acoustic contributions of the bridge components are analyzed in detail. The force transfer characteristics as well as the noise reduction effects of different track structures are thoroughly investigated, so as to provide reference for the future research on bridge-borne noise control.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502493
       
  • Wind-Induced Response Analysis of the Transmission Tower-Line System
           Considering the Joint Effect

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      Authors: Jia-Xiang Li, Chao Zhang, Xing Fu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Wind load is one of the main control loads of transmission tower-line systems. Numerical simulation is the main method for studying the structural wind-induced response. The establishment of a refined transmission tower simulation model is the basis for accurately analyzing the dynamic response of a transmission tower-line system under a wind load. This paper first considered the mechanical properties of bolted joints under cyclic loading and established a transmission tower-line system model considering the joint effects. Then, the wind load was generated by the harmonic superposition method, and the wind dynamic time-history analysis of the tower-line system was conducted. The influence of the joint effect on the wind-induced response of the transmission tower-line system was studied, and the effects of turbulence intensity and wind attack angle on the bolted joint slip effect were discussed. The results showed that the joint effect significantly increased the displacement response of the transmission tower subjected to wind loads and affected the normal service performance of the tower-line system. When the turbulence intensity is 10%, the top displacement of the tower model considering the joint effect is approximately 2 times that of the ideal rigid frame model. After considering the joint effect, the additional [math] effect caused by the increased displacement resulted in an increase in the stress of 75.6% members, and the maximum stress of the main member was located near the upper diaphragm of the tower leg. Therefore, considering the joint slip effect in angle steel transmission towers can improve the accuracy of the dynamic response analysis of transmission lines.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502523
       
  • Geometric Nonlinear Analysis of AngleSection Elements Based on Updated
           Lagrangian Formulation and Rigid Body Rule

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      Authors: Lingzhi Wang, Yi You, Weidong Liu, Qike Wei, Zhitao Yan, Xiaochun Nie, Y. B. Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Angle cross-section members are widely used in various transmission towers owing to their convenient connections, easy availability, simple production processes, and high efficiency. Such members are very susceptible to nonlinear behavior when subjected to abnormal or extreme loads. In this work, a new geometric stiffness matrix for thin-walled steel members with an angle cross-section is derived based on the principle of virtual displacement, rigid body rule and updated Lagrangian equations. The generalized displacement control (GDC) method is employed to deal with the issues of non-convergence at the extreme value point and rebound point in the geometric nonlinear analysis, which offers clear physical meaning and can adjust the loading direction. The geometric and the traditional elastic stiffness matrices derived in this work are applied during the prediction phase, while only the traditional elastic stiffness matrix is used in the correction phase. The comparisons of the results obtained by the proposed method with those in the previous literature and ANSYS numerical solutions show that the proposed method is sufficient to ensure the accuracy and applicability for addressing the structural geometrically nonlinear issues.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502535
       
  • Nonlinear Vibration of Truncated Open Conical Nanoshells Under Harmonic
           Excitation

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      Authors: Mohammad Mansouri, Morteza Dardel, Mohammad Hasan Ghasemi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The nonlinear forced vibration behavior of truncated open conical nanoshells is investigated in this paper. Nonlocal elasticity theory has been employed to modify the size-dependent effect of micro/nanostructure. Von Karman nonlinear strains are used to consider the geometric nonlinearity of the nanoshells. Using Hamilton’s principle, the equations of motion and boundary conditions of truncated open conical nanoshells are derived. Galerkin method is used to solve the governing equations. Then, to determine the nonlinear forced vibration behavior of truncated open conical nanoshells, complex averaging and arc-length continuation methods are employed. Finally, the effect of nonlocal parameters, cone apex angle, the amplitude of harmonic excitation, structural damping coefficient, and geometrical parameters on the nonlinear frequency response of the truncated open conical nanoshells are discussed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502559
       
  • LQR-Based Suspension for Heavy Vehicles Considering the Time-Varying
           Characteristics of Vehicle–Road Interaction

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      Authors: Buyun Zhang, Zewei Li, Chin An Tan, Zhiqiang Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The rapidly increasing demand for heavy vehicles in the transportation sector has led to more severe road damage and significantly higher road maintenance costs. Investigation of active suspension system incorporating vehicle–road interaction (VRI) can provide effective means to reduce the road damage and improve the ride comfort of vehicles. In this paper, an active vehicle suspension controller based on the strongly stable and robust linear–quadratic regulator (LQR) principle is developed for the time-varying VRI system. The coupled system is modeled by a quarter-car traveling on the road modeled by an Euler–Bernoulli beam resting on a viscoelastic foundation. Two types of road irregularities, deterministic sine wave and random, are considered in the numerical studies. A time-frozen technique, by which the linear time-varying system is converted to a time sequence of time-invariant systems, is applied to solve for the coupled responses. Three variables, the dynamic tire load, vehicle body acceleration, and suspension relative displacement, are used to assess the effectiveness of the LQR-based controller in comparison to the passive suspension system. The performance of the active control is investigated for different vehicle speeds, vehicle loads, and road profiles. Numerical studies show that the controller can effectively reduce the road damage and improve the ride comfort, with a slight increase in the suspension relative displacement. This work lays a useful foundation in the problem formulation and system parameter influences for future vehicle suspension design and road damage mitigation including VRI.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502560
       
  • New Analytic Free Vibration Solutions of L-Shaped Moderately Thick Plates
           by Symplectic Superposition

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      Authors: Yushi Yang, Dian Xu, Jinkui Chu, Guangping Gong, Yiming Chen, Rui Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      L-shaped moderately thick plates have widespread applications in diverse engineering structures. Exploring the benchmark analytic solutions for the free vibration of L-shaped moderately thick plates is important in order to accurately analyze and efficiently design structures. Nevertheless, analytical solutions, which serve as the benchmarks, have been rarely documented in previous literature due to the challenge of finding suitable solutions that satisfy both the governing higher-order partial differential equations (PDEs) and the boundary conditions of the plates. The symplectic superposition method was employed in our recently published study to present the benchmark vibration solutions of clamped rectangular moderately thick plates. In this study, we expand upon this method to solve the free vibration problem of L-shaped moderately thick plates. By employing domain decomposition, we construct an irregular domain by combining multiple rectangular domains. First, the construction of the superposition system is carried out, followed by the import of the sub-problems into the Hamiltonian system, utilizing the fundamental governing equations of the plate. Then, the sub-problems are resolved through the application of the symplectic geometry methodology in an analytical manner. Ultimately, the analytical solutions for frequencies and mode shapes are derived through ensuring the equivalence between the initial problem and the combination of sub-problems. The finite element method is used to validate and present a comprehensive analysis of the natural frequencies and mode shapes obtained from this method. This method possesses the benefits of rapid convergence and accurate precision, rendering it well suited for the analytic modeling of a broader range of plate-related problems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502572
       
  • System Fragility Analysis of Bridges Based on Response Variables
           Dimensionality Reduction

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      Authors: Boyang Zhu, Jinlong Liu, Junqi Lin
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Earthquake resistance of bridge structures is an important part of ensuring the functionality of transportation network systems. The structural system of a bridge is composed of multiple components, and the damage of different components may affect the function of the bridge, while the system seismic fragility analysis provides an effective way to evaluate the overall seismic performance of the bridge. In the past, the failure probability of a system is often estimated by the correlation between components, but the complex correlation between components brings certain difficulties to the actual calculation. In this paper, an efficient, accurate and universal method of system fragility analysis is proposed. This method decouples the correlation between components from the perspective of relative damage, adopts the critical demand-to-capacity ratio as the response variable of the system, realizing the dimensionality reduction of the response variables and simplifying the system fragility analysis from high-dimensional fragility analysis to one-dimensional fragility analysis. This methodology offers a viable solution to the challenges posed by the wide estimation of fragility boundaries in the boundaries estimation method and the complexities involved in analyzing correlation of components in the joint probability method. Comparison with traditional methods indicates that the proposed method exhibits high efficiency and convenience, making it suitable for practical engineering applications in system fragility computation. The proposed method holds great potential for future applications in the field of complex bridge structure fragility analysis, large-scale regional seismic damage prediction, rapid assessment, and beyond.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502638
       
  • Damped Vibration and Optimization of the Geometrical Parameters of FG
           Stiffened Cylindrical Shells Resting on Elastic Foundation Using GA

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      Authors: Saeid Bakhtiyar Aghamaleki, Mahdi Fakoor, Amir H. Hashemian
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Functionally graded materials with their structural characteristics, such as the type of distribution, the size of phases, gradually change from one surface to another and provide a wide range of applications. In this research, the optimization of geometric parameters of FG structure rested on the elastic foundation, including damping effects is of interest. The cylindrical shell’s material properties are assumed to vary smoothly and continuously across the thickness according to the power law distribution of the volume fraction of constituents. The governing equations of stiffened functionally graded cylindrical shell resting on an elastic foundation are obtained using Hamilton’s principle, the first-order shear deformation theory and finite element method. The numerical results are obtained for studying the effect of various factors, such as distribution of volume fraction, length and thickness, different boundary conditions, stiffness and damping coefficients, and also the natural frequency of the dynamic responses of the cylindrical shell. The damping effects are considered which were not presented in previous studies. The frequency responses of the cylindrical FGM shell resting on elastic foundation were obtained by adding the damping term into the governing equations. Besides, analytical formulation results were considered as an objective function (input) for optimization in Genetic Algorithms. Finally, the compatibility of the analytical modeling results with the commercial finite element software was checked which showed good agreement.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S021945542450264X
       
  • Comparison Study of the Location-Related Damage Sensitivity and Structural
           Damage Index with Sensitivity Enhancement for Beam Structure

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      Authors: Panjie Li, Tongkuai Zhao, Jian Zhang, Jinke Li, Shengli Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The primary requirement for vibration-based structural damage identification is to develop the damage index with higher damage sensitivity. Although it is believed that higher order mode means more sensitivity to damage, what is the quantitative relationship between damage sensitivity of different orders and how to carry out multi-mode fusion lack theoretical guidance. This paper implements the comparison study of the location-related damage sensitivity for different mode shape curvatures and then proposes a structural damage index with sensitivity enhancement for beam structure. First, the damage sensitivity of the mode shape curvature of beam structures at different orders is compared in theory. It reveals that the damage sensitivity is location-dependent, and the second-order mode in the even 16.6% region is more sensitive than the third-order mode in the simply supported beam. Second, a structural damage index with sensitivity enhancement for beam structure is proposed according to the relationship between the damage sensitivity of mode shape curvature at different orders and locations. Third, a simply supported beam model and a steel stringer bridge model with multiple main girders are both investigated to illustrate the comparison results of the damage sensitivity at different orders and the advantages of the proposed structural damage index. It shows that the confused damage sensitivities are very common between different mode orders, the sensitivity-enhanced damage index that considers the damage location always shows certain degree of improvement of damage indication ability in different damage areas. Finally, the effectiveness and accessibility of the proposed method are verified by a simply supported beam experiment.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502663
       
  • Dynamic Characteristics of Bistable Vibration Energy Harvester
           Incorporating Electromagnetic Generator

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      Authors: Jiahui You, Bo Tang, Ming Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Although various vibration energy harvesters have been designed over the past few decades, efforts to develop efficient, broadband energy harvesters continue. This work provides a detailed insight into a bistable vibration harvester subjected to correlated Gaussian white noise, with the friction between the rack and pinion described by the slip-stick model. Using the harmonic balance method, the frequency response curve of the amplitude under different mass ratios is discussed. The system response will be enhanced with an increased mass ratio for sinusoidal excitation, but not in the case of random excitation. By employing the stochastic average of the energy envelope, the dynamical governing equation of the harvester is solved, and the probability density functions (PDFs) under different damping coefficients, nonlinear stiffness of the restoring force, and excitation intensities are derived. The results are compared with those from Monte Carlo simulations (MCS) and show good accuracy. The results reveal the presence of P-bifurcations. When the nonlinear stiffness and damping coefficient vary, the number of peaks in the PDFs of system displacement and velocity changes. By adjusting the system parameters, the motion of the system can be significantly enhanced.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502675
       
  • A Dynamic Modeling Method for Soft Pneumatic Robotic Arms Considering Both
           Geometric Nonlinearity and Visco-Hyperelasticity

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      Authors: Tao Wang, Xi Wang, Guoqiang Fu, Caijiang Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This work proposes a new dynamic modeling approach that integrates the principle of virtual power and a spring–damper–fluid equivalent method. It is able to simultaneously consider the geometric and material nonlinearity including hyperelasticity and viscoelasticity of the soft robotic arm. Meanwhile, the nonuniform deformation of the soft arm wall can be introduced into the model based on the equivalent model. A general prototype of soft robotic arms is fabricated and validation experiments of three pneumatic actuation modes are carried out. A maximum position error of 3.64[math]mm at the end of the soft arm is obtained with an eight-segment theoretical model for the 280[math]mm long and 30[math]mm thick prototype in an approximate step actuation test with a maximum pneumatic pressure of 11.5[math]kPa. The comparisons between the theoretical prediction and experimental results demonstrate a high accuracy of the proposed modeling method. Besides, simulations of dynamic motions under in-plane and out-of-plane actuation are carried out respectively, illustrating that the proposed method has the ability to describe a variety of actuation forms. The proposed dynamic modeling method provides a new way for modeling the soft robotic arms and has guiding significance for the design and control of soft robotic arms.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502717
       
  • Analysis of Natural Vibration Characteristics of Modified Timoshenko
           Cracked Beam

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      Authors: Yabo Wang, Hongbing Yuan, Haicun Song, Changtai Gong, Peng Zhang, Jing Huang, Rongsheng Du
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study utilizes the transfer matrix method to analyze the modified Timoshenko beam with and without cracks. The massless torsional spring is assumed to represent the section where the crack is located. The matrix equation is simplified using boundary conditions and solved using MATLAB. Additionally, the influence of different crack depths and positions on the first three natural frequencies is compared to finite element analysis using three common types of beams as examples. The results indicate that increasing the crack depth leads to a decrease in the natural frequency of the beam. However, the impact on certain specific positions is insignificant, with a maximum error between the two methods not exceeding 2.73%. Furthermore, the study investigates the influence of crack depth on natural frequency under different span-to-height ratios. The findings reveal that increasing the span-to-height ratio reduces the influence of crack depth on natural frequency, thereby validating the proposed method and its applicability in modified Timoshenko cracked beams.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502729
       
  • Analysis of In-Plane Impact Mechanical Properties of Centre-Symmetric
           Chiral Honeycomb

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      Authors: Fumo Yang, Xiaolin Deng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, two center-symmetric chiral honeycombs (CSCH-1 and CSCH-2) were designed through a center-symmetric approach. Corresponding samples were prepared using 3D printing technology, and in-plane impacts were carried out under quasi-static experiments with the conventional chiral honeycomb (CH). The experimental results show that CSCH-1 and CSCH-2 have better load-bearing capacity and energy-absorbing properties than CH. The mean stress of the two increased by 40% and 60%, and the energy absorption (EA) increased by 92.10% and 101.90%, respectively, compared to CH. Furthermore, the design of CSCH-2 effectively controls the expansion and deformation of the structure, and shows better negative Poisson’s ratio effect. Subsequent finite element modeling was performed using the finite element software Abaqus/Explicit, and the accuracy of the finite element model was verified. Furthermore, the in-plane impact mechanical behavior of CH, CSCH-1, and CSCH-2 was investigated at different impact velocities, various nodal circle radii, and different orthogonal array ratios.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S0219455424502754
       
  • An Iterative Augmented Unscented Kalman Particle Filter for Simultaneous
           State-Parameter-Input Estimation for Structural Systems Subjected to
           Gamma-Distribution Noise

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      Authors: Tianhao Yu, Jingfeng Wang, Wanqian Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Simultaneous estimations of the states, parameters and unknown inputs of nonlinear structural systems subjected to non-Gaussian noise are essential, because the inputs are not always available and the system noise is not always Gaussian. However, filters developed for this task require the inter-story drift measurements to be “fused” with the acceleration measurements to avoid the “drift phenomenon”. Because inter-story drifts may be inconvenient to obtain in practice, it is more desirable to use acceleration measurements only. To this end, this study develops a novel iterative augmented unscented Kalman particle filter (IAUKPF) for the simultaneous state-parameter-input estimation for systems subjected to non-Gaussian noise. The iterative strategy proposed in this study effectively corrects the “drift phenomenon” when only acceleration measurements are incorporated, so that the accuracies of the estimated unknown inputs are promoted. The importance density of the particle filter at each time step is provided by the augmented unscented Kalman filter so that the filter takes the best known information into consideration. Numerical examples of nonlinear structural systems affected by non-Gaussian noise are adopted to examine the effectiveness of the proposed IAUKPF.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-08T08:00:00Z
      DOI: 10.1142/S021945542450278X
       
  • Nonlinear Free Vibration Analysis in Micro-Rotating Systems

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      Authors: Mayank Ahirwar, Barun Pratiher
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Rotating machinery with flexible shafts finds application across a broad spectrum, ranging from everyday household appliances to heavy-duty industrial setups. These machines harness substantial rotational energy, which in turn induces vibrations. In step with industrial progress, modern devices are becoming smart, intelligent, and compact, with the help of microscopic devices known as Micro-Electro-Mechanical Systems (MEMS), incorporating electrical and moving mechanical parts. One noteworthy category within MEMS is Power MEMS. Operating at speeds exceeding a million revolutions per minute, these systems are employed in compact energy supply solutions for small-scale electronics, diminutive ground robots and unmanned airborne vehicles, all of which demand efficient power sources. This paper addresses the rotor dynamics associated with micro-rotating systems. The intricate dynamics and nonlinear issues witnessed in macro-scale systems are equally relevant to these tiny systems. This is why recognizing the traits and behavior of these small-scale systems and analyzing their dynamic actions within the operational context becomes a fundamental topic that influences design, control, maintenance, and safety considerations. Incorporating low friction bearings and rotor dynamics into mathematical formulation yields results that are nearly perfect models. Therefore, this study aims to conduct a comprehensive nonlinear analysis of the micro-rotor, considering the nonlinearity arising from the substantial deformation of the shaft. The influence of small-scale effects, which hold significance at the micron scale, is addressed utilizing modified couple stress theory. The study employs the Euler–Bernoulli beam theory while accounting for the axial stretching effect under conditions of significant deformation. The dynamics of the rotor, including essential parameters like spin speed, disk placement, and size dependency, are thoroughly investigated through a comprehensive parametric study presented in this work.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-01T08:00:00Z
      DOI: 10.1142/S0219455424400182
       
  • Nonlinear Instabilities of TPMS Cellular Units Under Axially Loaded
           Conditions

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      Authors: Hao Fu, Xu Huang, Sakdirat Kaewunruen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In recent years, significant research has been conducted to explore the use of 3D triply periodic minimal surface (TPMS) structures for their exceptional vibrational damping properties and their ability to provide a continuous, smooth surface. The emergence of 3D printing has enabled the application of TPMS structures in fields such as medicine and aviation. In civil engineering, the compressive capacity of structures is a fundamental parameter in structural design. To evaluate the potential of porous TPMS structures in civil engineering, we have designed and manufactured four types of Skeletal-TPMS units using Stereolithography (SLA) technology. Axially loaded tests and nonlinear finite element method (NFEM) simulations have been performed to investigate the compressive strength and stiffness of the units. Our findings indicate that compared to solid blocks, the compressive strength of Skeletal-TPMS units decreases by 71.3% to 82.6%, and the stiffness decreases by 64.9% to 79.2%. The Skeletal-SP units show better compressive resistance than Skeletal-IWP units. This study provides new valuable insights for structural design and applications using TPMS structures in civil engineering.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-02-01T08:00:00Z
      DOI: 10.1142/S0219455424502614
       
  • Wave Propagation in the Semi-Infinite Functionally Graded Porous Plates
           Reinforced with Graphene Platelets

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      Authors: Jun Zhu, Zhengzheng Wang, Liqiang Zhang, Helong Wu, Li Zhao, Han Zhang, Huaping Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the wave propagation in the graphene platelets (GPLs)-enhanced functionally graded porous plates. The governing equations of motion are obtained using the first-order shear deformation plate theory (FSDT). Subsequently, the equations are transformed into the state-space form. The wave dispersion relation is derived by solving the state space equation by means of the method of reverberation-ray matrix and the accuracy of this approach is validated through a comparative analysis with the results from relevant literature. In addition, parametric analyses are carried out, including boundary conditions, porosity coefficient, GPL mass fraction, porosity distribution, GPL distribution, and thickness-to-width ratio, on the dispersion behavior of functionally graded GPLs-reinforced porous plates. The use of GPLs in these composites is particularly promising, and the findings offer valuable insights into the design of composites with tailored properties for specific engineering applications.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S0219455424502456
       
  • Effect of Ground Motion Time–Frequency Non-Stationarity on Seismic
           Response of High-Speed Railway Simply Supported Bridge Based on Wavelet
           Packet Transform

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      Authors: Biao Wei, Andong Lu, Lizhong Jiang, Lu Yan, Zechuan Sun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Time–frequency non-stationarity is a ground motion characteristic which is frequently neglected in current seismic design and research. This paper studies its impact on the seismic response of high-speed railway simply supported bridge (HSRSSB). A method for generating time–frequency stationary earthquakes (TFSEs) and time–frequency non-stationary earthquakes (TFNSEs) using wavelet packet transform is proposed. A finite element model of a three-span HSRSSB is established using OpenSees. The seismic response is obtained through non-linear dynamic time history analysis, and the fragility curves of bridge components and system are calculated through incremental dynamic analysis. Finally, the reasons for the differences are analyzed by comparing the differences in seismic response of bridge, component fragility and system fragility under two groups of ground motion. The results show that the time–frequency non-stationarity of ground motion has an effect on the bridge response and fragility under strong earthquakes. TFNSE will lead to larger ground motion response, and the damage probability of bridge components and systems is higher. The reason is related to the damage and period extension of bridges under ground motion. Structures with prolonged period anti-seismic measures need to pay attention to this effect.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S021945542450247X
       
  • A Unified Model for Investigating the Propagation of SH Surface Waves in a
           Piezoelectric Layered Medium

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      Authors: Xun Fang, Linyao Wang, Jia Lou, Hui Fan, Aibing Zhang, Jianke Du
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, a thorough analysis is conducted to examine the propagation characteristics of SH surface waves in a layered medium with a nanoscale piezoelectric guiding layer deposited on an isotropic elastic substrate. Specifically, a two-dimensional analytical model is established, within which the effects of strain gradient, electric field gradient, inertia gradient, and flexoelectricity are considered, as well as interfacial imperfections at the interface between the piezoelectric guiding layer and the elastic substrate, which are characterized by spring models. Within the framework of the variational principle, the governing equations, boundary conditions, and continuity conditions at the interface are derived. Based on these equations, the dispersion relations for SH surface waves are deduced and numerically solved for both the electrically open-circuit and electrically short-circuit cases. A comprehensive investigation of the dispersion relations for the fundamental mode of SH surface waves is subsequently provided, with a detailed discussion on the influence of critical factors. The developed theoretical model, encompassing various size effects observed in nano-scale structures, enables a more precise prediction of surface wave propagation behavior, thereby enhancing the design and application of surface acoustic wave devices.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S0219455424502481
       
  • On the Dynamic Performance of Higher-Order Smart Metal Foam Arches Coated
           with Piezoelectric Nanocomposite Actuators

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      Authors: Wenbo Yang, Changjie Wu, Yasser Alashker
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study delves into the dynamic characteristics of intelligent arches composed of metal foams, augmented with piezoelectric nanocomposite actuators. These arches are represented within the polar coordinate system, utilizing a higher-order shear and normal deformation theory that eliminates the need for shear correction factors. The structural properties exhibit thickness-dependent variations following predetermined functions. The model operates within a thermal environment and is supported by a Winkler–Pasternak elastic substrate. Hamilton’s principle is employed to derive the equations governing the structure’s motion. In solving these equations for a scenario with simply supported ends, Fourier series functions are employed as an analytical method. The outcomes are cross-verified against previously published studies with simpler configurations. The investigation explores the impacts of various critical parameters on the dynamic response of the structure. Findings reveal that an increase in pores within the metal foam core decreases the frequency, whereas an increase in the volume fraction of carbon nanotubes has the opposite effect. The primary objective of this study is to design and fabricate more efficient smart structures, through a comprehensive understanding and optimization of the behavior of metal foam arches when integrated with piezoelectric components.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S021945542450250X
       
  • Generalized Thermoelasticity of Two-Dimensional Bounded Media Under
           Moving Heat Source: A Meshless Approach

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      Authors: Xiaofei Liu, Feng Pan, Dapeng Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this work, the coupled generalized thermoelasticity of two-dimensional finite domain subjected to moving heat source is investigated. The generalized thermoelasticity is based on Lord–Shulman (LS) theory, and the moving heat source is considered to move along the [math]-axis at the middle of the domain with constant velocity. The meshless method, because of continuous moving of approximations over the problem domain, is the best numerical method for problems with moving loads. So, for solving the governing equations, the meshless Galerkin weak form is employed. In the applied meshless method, the moving least square (MLS) shape functions are used for approximating the field variables in each influence domain. Also, for solving the final equations in the time domain, the Newmark time marching method is used. The results show that a moving source with a velocity equal to the temperature’s wave speed exhibit the maximum peak values of temperature, displacement and stress in the domain, and when the temperature wave speed and the elastic wave speed are equal, the moving heat source at this speed drastically increases the peak values of stress, displacement and temperature.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S0219455424502511
       
  • A Novel Straight Beam Element for Lateral-Distortional Deformation
           Analysis of Frames and Curved Beams Made of Monosymmetric I-Sections

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      Authors: Y. Z. Liu, Y. B. Yang, X. H. Liu, D. Z. Guo, H. Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Conventional beam elements ignoring distortion may overestimate the lateral resistance of frames and curved beams made of monosymmetric I-sections. This paper introduces two new distortional modes represented by mechanical couples relative to twisting and shearing of the two flanges that are opposite in directions but unequal in magnitudes. A straight beam element with nine degrees of freedom (DOFs) per node, including the conventional three translations, three rotations, warping and the new two distortions, is newly derived. This allows all the DOFs of the connected elements at a common joint to be easily transformed to the global coordinates for stiffness assembly. As a result, the warping–distortion compatibility problem that occurs in frames and curved beams is resolved. In the numerical examples, the results produced by the present beam element is demonstrated to agree excellently with the shell-element solutions for the lateral-distortional deformation of the angled frame and curved beam. It is observed that the cross-sectional distortion effect becomes extremely significant for angled frames of short unbraced length and for curved beams of high curvature.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-29T08:00:00Z
      DOI: 10.1142/S021945542471007X
       
  • Numerical Prediction of Ballistic Performance of Thin Concrete Plate

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      Authors: Kamran, Mohd Asif, M. A. Iqbal
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This research explores the ability of 60[math]mm thick reinforced concrete (RC) plates to resist impacts from ogive-nosed hard steel projectiles. The projectiles used in the present study have a diameter of 19[math]mm, a length of 200[math]mm, and a mass of 0.4[math]kg impacted on the RC plates with incident velocities ranging from 92[math]m/s to 161[math]m/s. Numerical simulations were conducted using ABAQUS/Explicit finite element software to validate the experimental results. The Holmquist–Johnson–Cook (HJC) material model was employed to simulate the constitutive behavior of concrete, while the Johnson–Cook (JC) material model was used to simulate the material response of reinforcing steel bars. The residual velocities obtained from the simulations closely matched the actual experimental results, showing a polynomial correlation with the incidence velocities of the projectiles. Moreover, the experimentally and numerically determined ballistic limit for the 60[math]mm thick RC plate was found to be 108[math]m/s and 109.5[math]m/s, respectively. In contrast, the ballistic limit calculated using empirical mathematical expressions was 107.4[math]m/s. This alignment between predicted, calculated, and actual ballistic limits underscores the reliability and accuracy of both numerical and empirical approaches.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-24T08:00:00Z
      DOI: 10.1142/S0219455424400170
       
  • Frequency Identification of Equal-Span Continuous Girder Bridge Based on
           Moving Vehicle Responses

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      Authors: Kui Luo, Siqi Li, Xiuyan Wang, Xuan Kong, Tengjiao Jiang, Pengcheng Yin
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The indirect method for bridge modal identification based on the response of moving vehicles has attracted widespread attention in recent years. However, most existing studies only focus on the simply supported bridge, while continuous girder bridges are widely used in practical engineering. Therefore, this study proposes an indirect frequency identification method for continuous girder bridges. First, the mode shape formula of the equal-span continuous beam is deduced using the three-moment equations, and the analytical solution of the vehicle vibration response is deduced via the vehicle–bridge coupled vibration theory. Second, the derived analytical solution is verified through numerical analysis results and field test results. Finally, the effects of bridge and vehicle parameters on the frequency identification accuracy are analyzed. The results show that a reasonable frequency of the trailer should be selected to avoid the resonance between the vehicle and the bridge for better performance. The research findings can provide a reference for the indirect identification of continuous girder bridges based on the response of moving vehicles.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-24T08:00:00Z
      DOI: 10.1142/S0219455424502584
       
  • Global Displacement Reconstruction of Lattice Tower Using Limited
           Acceleration and Strain Sensors

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      Authors: Xing Fu, Qing Zhang, Liang Ren, Hong-Nan Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Displacement is an important parameter for evaluating structural performance. However, the accurate measurement of global dynamic displacement remains a challenging task. To solve this problem, this paper proposes a global dynamic displacement reconstruction method for lattice tower structures, fusing limited acceleration and strain data. First, the strain-displacement mapping method for cantilever beams with variable cross-sections is presented and then extended to lattice towers. Thereafter, a modified multi-rate data fusion algorithm incorporating Kalman filtering and the proposed strain-displacement mapping methods is developed to fuse the acceleration and strain data to reconstruct the global dynamic displacement of the tower. The numerical simulation, model test and full-scale test demonstrate that the reconstructed dynamic displacements using the proposed method agree well with the reference values in both the time and frequency domains, and the parametric analysis has also been carried out, exhibiting great robustness and high reconstruction accuracy.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-22T08:00:00Z
      DOI: 10.1142/S0219455424502420
       
  • Stability in Parametric Resonance of a Controlled Stay Cable with Time
           Delay

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      Authors: Jian Peng, Hui Xia, Hongxin Sun, Stefano Lenci
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The stability of the parametric resonance of a controlled stay cable with time delay is investigated. The in-plane nonlinear equations of motion are initially determined via the Hamilton principle. Then, utilizing the method of multiple scales, the modulation equations that govern the nonlinear dynamics are obtained. These equations are then utilized to investigate the effect of time delays on the amplitude and frequency-response behavior and, subsequently, on the stability of the parametric resonance of the controlled cable, that it is shown to depend on the excitation amplitude and the commensurability of the delayed-response frequency to the excitation frequency. The stability region of the parametric resonance is shifted, and the effects of control on the cable become worse by increasing time delay. The work plays a guiding role in the parametric design of the control system for stay cables.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-05T08:00:00Z
      DOI: 10.1142/S021945542450233X
       
  • Active Control of Quasi-Zero-Stiffness Vibration Isolator with Variable
           Load

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      Authors: Ke Sun, Jie Tang, Yukang Yang, Bolong Jiang, Yinghui Li, Dengqing Cao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Quasi-zero-stiffness (QZS) isolator has great application potential in the field of low-frequency vibration isolation due to its high-static and low-dynamic (HSLD) nonlinear stiffness characteristic, but it is precisely this characteristic that makes it very sensitive to load changes. Once the load changes, causing it to deviate from the equilibrium position, it no longer qualifies zero-stiffness characteristic, and the vibration isolation capacity will be significantly decrease. To make the QZS isolator possess variable load capacity and be more suitable for engineering practice, an active QZS vibration isolator based on electromagnetic actuator is designed in this paper, which eliminates the influence of load changes through the active force of the electromagnetic actuator. First, the dynamic equation of the isolator is established by Newton–Euler method, and the dynamic characteristic of the isolator under standard load and load variations are analyzed through improved incremental harmonic balance (IHB) method based on discrete Fourier transform (DFT). Next, the improved particle swarm optimization (PSO) algorithm are employed to optimize the Proportion Integration Differentiation (PID) controller parameters. Then, the vibration isolation performance of QZS isolator in controlled and uncontrolled and linear systems in the same control state are compared in frequency domain and time domain, respectively. Finally, the performance of active QZS isolator under load variation is discussed. The results indicate that the isolation performance of the QZS isolator under active control is significantly better than in uncontrolled conditions and the controlled linear system. When the load changes, real-time compensation through the actuator output control force can also enable the QZS isolator to achieve a better vibration isolation performance.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-05T08:00:00Z
      DOI: 10.1142/S0219455424502432
       
  • On Flexural Wave Dispersion of a Higher-Order Metamaterial Sandwich
           Composite Plate Based on a Visco-Pasternak Foundation

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      Authors: Mohammad Mahinzare, Farzad Ebrahimi, Abbas Rastgoo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper elaborates on the wave propagation characteristics of a smart sandwich plate consisting of smart piezo composite layers on a plate’s upper and lower borders via an auxetic core. This study’s equation of motion was derived using a refined version of the Shear-deformation theory at a higher order, or HSDT. Additionally, detecting the properties of the auxetic core and piezoelectric composite layers employs a micromechanical model. The fundamental equations of the smart sandwich plates were formulated utilizing the Hamiltonian principle and Maxwell’s law. Then, the governing equations of a sandwich plate are solved using an exponential form and an analytical method. Furthermore, the phase velocity of the intelligent sandwich plate is provided based on the layer thicknesses of the auxetic core and thicknesses of intelligent piezoelectric composite layers. In addition, each figure calculates and presents the weight of the Winkler–Pasternak coefficient, the viscoelastic substances factor, the source of the outside electricity, and the volume percent of reinforcement in the matrix on the phase velocity.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-04T08:00:00Z
      DOI: 10.1142/S0219455424502286
       
  • Response Characteristics and Suppression of Vortex-Induced Vibration of
           the Flexible Cable

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      Authors: Yan Han, Xu Chen, Xuhui Zhou, Junfeng Yang, Peng Hu, Hubin Yan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To investigate the vortex-induced vibration (VIV) of a flexible cable in the uniform flow, experiments were conducted using a flexible cable with an external diameter of 80[math]mm and a length of 10.48[math]m in the wind tunnel. The characteristics of multi-modal VIV, time-frequency and traveling wave behavior of the flexible cable were analyzed. Moreover, the effects of twist direction, diameter and the single/double helical wire on the VIV characteristics of the flexible cable were investigated. It is found that the flexible cable experiences single and multi-modal VIVs in uniform flow at different incoming wind speeds, respectively. For the multi-modal VIV of the flexible cable, the vibration over the time history is dominated by two adjacent modal frequencies and shows a phenomenon of beat vibration. The multi-modal VIV responses of the flexible cable show a mix of standing and traveling wave behaviors, in which the effects of standing wave are more pronounced near both ends and the effects of traveling wave are more dominant in the middle region of the flexible cable. The twist direction of the helical wire has little effect on the VIV responses of the flexible cable. The VIV amplitudes of the flexible cable can be reduced by a single helical wire. With the diameter of the helical wire increases, the suppression effects of the single or double helical wire on the VIV of the flexible cable can be improved. Particularly, the double helical wire with diameter 0.10D can effectively suppress the VIV of the flexible cable.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-03T08:00:00Z
      DOI: 10.1142/S0219455424502353
       
  • Vibration Characteristics of FML Cylindrical Shell Bonded by Thin
           Piezoelectric Actuator and Sensor Layer with and Without Fluid–Structure
           Interaction Resting on Pasternak Elastic Foundation

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      Authors: M. Khademi-Kouhi, A. Ghasemi-Ghalebahman, A. Farrokhabadi, M. R. M. Aliha
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The present study investigates the vibration analysis of cylindrical shells composed of fiber metal laminate (FML) with embedded piezoelectric layers, undergoing fluid-structure interaction (FSI) and resting on a Pasternak elastic foundation based on the principles of three-dimensional elasticity theory. Using the state space approach, the equations of motion were derived under simply supported boundary conditions. The natural frequencies of the FML cylindrical shell, accounting for the presence of a moving fluid, were computed by solving the eigenfrequency equations. The study examined the influence of various parameters, including boundary conditions, length-to-radius ratio, fluid type, fluid velocity, circumferential wave number, and radius-to-thickness ratio, on glass-reinforced aluminum laminate (GLARE), aramid-reinforced aluminum laminate (ARALL), and carbon-reinforced aluminum laminate (CARALL). A constant composite/metal volume ratio was assumed. The results obtained were validated by comparing with natural frequency values from the existing literature, confirming the agreement and convergence with previous studies. The results confirm that the highest natural frequency values are assigned to the CARALL, ARALL and GRALE structures in descending order. Furthermore, an increase in fluid flow velocity through the cylindrical shell correlates with a reduction in natural frequency.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2024-01-03T08:00:00Z
      DOI: 10.1142/S0219455424502389
       
 
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  Subjects -> BUILDING AND CONSTRUCTION (Total: 139 journals)
    - BUILDING AND CONSTRUCTION (131 journals)
    - CARPENTRY AND WOODWORK (8 journals)

BUILDING AND CONSTRUCTION (131 journals)                     

Showing 1 - 35 of 35 Journals sorted alphabetically
Advances in Building Energy Research     Hybrid Journal   (Followers: 11)
Asian Journal of Civil Engineering     Hybrid Journal   (Followers: 3)
Australasian Journal of Construction Economics and Building     Open Access   (Followers: 9)
Baltic Journal of Real Estate Economics and Construction Management     Open Access   (Followers: 4)
Bautechnik     Hybrid Journal   (Followers: 1)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 1)
Building Acoustics     Hybrid Journal   (Followers: 4)
Building Services Engineering Research & Technology     Hybrid Journal   (Followers: 3)
Buildings     Open Access   (Followers: 11)
BUILT : International Journal of Building, Urban, Interior and Landscape Technology     Open Access   (Followers: 3)
Built Environment Inquiry Journal     Open Access  
Built Environment Project and Asset Management     Hybrid Journal   (Followers: 13)
Case Studies in Construction Materials     Open Access   (Followers: 8)
Cement     Open Access   (Followers: 6)
Cement and Concrete Composites     Hybrid Journal   (Followers: 20)
Cement and Concrete Research     Hybrid Journal   (Followers: 20)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 5)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 4)
Change Over Time     Full-text available via subscription   (Followers: 3)
City, Culture and Society     Hybrid Journal   (Followers: 25)
Cityscape     Full-text available via subscription   (Followers: 10)
Clay Technology     Full-text available via subscription  
Construction Economics and Building     Open Access   (Followers: 4)
Construction Engineering     Open Access   (Followers: 9)
Construction Management and Economics     Hybrid Journal   (Followers: 24)
Construction Research and Innovation     Hybrid Journal   (Followers: 5)
Construction Robotics     Hybrid Journal   (Followers: 5)
Corporate Real Estate Journal     Full-text available via subscription   (Followers: 7)
Dams and Reservoirs     Hybrid Journal   (Followers: 4)
Developments in the Built Environment     Open Access   (Followers: 1)
Energy and Built Environment     Open Access  
Engineering Project Organization Journal     Hybrid Journal   (Followers: 6)
Engineering, Construction and Architectural Management     Hybrid Journal   (Followers: 14)
Environment and Urbanization Asia     Hybrid Journal   (Followers: 2)
Facilities     Hybrid Journal   (Followers: 7)
FUTY Journal of the Environment     Full-text available via subscription  
Glass Structures & Engineering     Hybrid Journal   (Followers: 1)
HBRC Journal     Open Access  
Housing and Society     Hybrid Journal   (Followers: 5)
HVAC&R Research     Hybrid Journal  
Indoor and Built Environment     Hybrid Journal   (Followers: 3)
Informes de la Construcción     Open Access  
Intelligent Buildings International     Hybrid Journal   (Followers: 2)
International Journal of Advanced Structural Engineering     Open Access   (Followers: 26)
International Journal of Architectural Computing     Full-text available via subscription   (Followers: 6)
International Journal of Built Environment and Sustainability     Open Access   (Followers: 3)
International Journal of Concrete Structures and Materials     Open Access   (Followers: 10)
International Journal of Construction Engineering and Management     Open Access   (Followers: 9)
International Journal of Construction Management     Hybrid Journal   (Followers: 4)
International Journal of Disaster Resilience in the Built Environment     Hybrid Journal   (Followers: 5)
International Journal of Housing Markets and Analysis     Hybrid Journal   (Followers: 11)
International Journal of Masonry Research and Innovation     Hybrid Journal  
International Journal of Protective Structures     Hybrid Journal   (Followers: 6)
International Journal of River Basin Management     Hybrid Journal   (Followers: 1)
International Journal of Structural Stability and Dynamics     Hybrid Journal   (Followers: 9)
International Journal of Sustainable Building Technology and Urban Development     Hybrid Journal   (Followers: 14)
International Journal of Sustainable Construction Engineering and Technology     Open Access   (Followers: 8)
International Journal of Sustainable Real Estate and Construction Economics     Hybrid Journal   (Followers: 2)
International Journal of the Built Environment and Asset Management     Hybrid Journal   (Followers: 5)
International Journal of Ventilation     Full-text available via subscription  
Journal for Education in the Built Environment     Open Access   (Followers: 4)
Journal of Aging and Environment     Hybrid Journal   (Followers: 4)
Journal of Architecture, Planning and Construction Management     Open Access   (Followers: 12)
Journal of Asian Architecture and Building Engineering     Open Access  
Journal of Building Construction and Planning Research     Open Access   (Followers: 10)
Journal of Building Engineering     Hybrid Journal   (Followers: 5)
Journal of Building Pathology and Rehabilitation     Hybrid Journal  
Journal of Building Performance Simulation     Hybrid Journal   (Followers: 6)
Journal of Civil Engineering and Construction Technology     Open Access   (Followers: 14)
Journal of Civil Engineering and Management     Open Access   (Followers: 9)
Journal of Computing in Civil Engineering     Full-text available via subscription   (Followers: 23)
Journal of Construction Business and Management     Open Access   (Followers: 2)
Journal of Facilities Management     Hybrid Journal   (Followers: 4)
Journal of Legal Affairs and Dispute Resolution in Engineering and Construction     Full-text available via subscription   (Followers: 4)
Journal of Property, Planning and Environmental Law     Hybrid Journal   (Followers: 8)
Journal of Structural Fire Engineering     Full-text available via subscription   (Followers: 4)