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
A+BE : Architecture and the Built Environment     Open Access   (Followers: 19)
Academia : Architecture and Construction     Open Access   (Followers: 2)
ACI Structural Journal     Full-text available via subscription   (Followers: 20)
Advances in Building Education     Open Access   (Followers: 4)
Advances in Building Energy Research     Hybrid Journal   (Followers: 11)
Anales de Edificación     Open Access  
Asian Journal of Civil Engineering     Hybrid Journal   (Followers: 2)
Australasian Journal of Construction Economics and Building     Open Access   (Followers: 8)
Baltic Journal of Real Estate Economics and Construction Management     Open Access   (Followers: 5)
Bautechnik     Hybrid Journal   (Followers: 1)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 1)
Building & Management     Open Access   (Followers: 2)
Building Acoustics     Hybrid Journal   (Followers: 4)
Building Services Engineering Research & Technology     Hybrid Journal   (Followers: 3)
Buildings     Open Access   (Followers: 7)
BUILT : International Journal of Building, Urban, Interior and Landscape Technology     Open Access   (Followers: 2)
Built Environment Inquiry Journal     Open Access  
Built Environment Project and Asset Management     Hybrid Journal   (Followers: 13)
Built-Environment Sri Lanka     Full-text available via subscription  
Case Studies in Construction Materials     Open Access   (Followers: 8)
Cement     Open Access   (Followers: 1)
Cement and Concrete Composites     Hybrid Journal   (Followers: 17)
Cement and Concrete Research     Hybrid Journal   (Followers: 17)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 4)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 3)
Change Over Time     Full-text available via subscription   (Followers: 3)
City, Culture and Society     Hybrid Journal   (Followers: 23)
Cityscape     Full-text available via subscription   (Followers: 10)
Clay Technology     Full-text available via subscription  
Concreto y cemento. Investigación y desarrollo     Open Access  
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: 4)
Construction Robotics     Hybrid Journal   (Followers: 4)
Corporate Real Estate Journal     Full-text available via subscription   (Followers: 4)
Dams and Reservoirs     Hybrid Journal   (Followers: 3)
Developments in the Built Environment     Open Access  
Energy and Built Environment     Open Access  
Engineering Project Organization Journal     Hybrid Journal   (Followers: 6)
Engineering, Construction and Architectural Management     Hybrid Journal   (Followers: 11)
Environment and Urbanization Asia     Hybrid Journal   (Followers: 2)
Facilities     Hybrid Journal   (Followers: 4)
Frontiers in Built Environment     Open Access   (Followers: 1)
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: 6)
HVAC&R Research     Hybrid Journal  
Indoor and Built Environment     Hybrid Journal   (Followers: 4)
Informes de la Construcción     Open Access  
Intelligent Buildings International     Hybrid Journal   (Followers: 2)
International Journal of Advanced Structural Engineering     Open Access   (Followers: 25)
International Journal of Air-Conditioning and Refrigeration     Hybrid Journal   (Followers: 12)
International Journal of Architectural Computing     Full-text available via subscription   (Followers: 5)
International Journal of Built Environment and Sustainability     Open Access   (Followers: 3)
International Journal of Concrete Structures and Materials     Open Access   (Followers: 9)
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: 4)
International Journal of Housing Markets and Analysis     Hybrid Journal   (Followers: 9)
International Journal of Masonry Research and Innovation     Hybrid Journal  
International Journal of Protective Structures     Hybrid Journal   (Followers: 4)
International Journal of River Basin Management     Hybrid Journal  
International Journal of Structural Stability and Dynamics     Hybrid Journal   (Followers: 7)
International Journal of Sustainable Building Technology and Urban Development     Hybrid Journal   (Followers: 11)
International Journal of Sustainable Construction Engineering and Technology     Open Access   (Followers: 7)
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: 3)
Journal of Aging and Environment     Hybrid Journal   (Followers: 4)
Journal of Architecture, Planning and Construction Management     Open Access   (Followers: 11)
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: 4)
Journal of Building Materials and Structures     Open Access   (Followers: 2)
Journal of Building Pathology and Rehabilitation     Hybrid Journal  
Journal of Building Performance Simulation     Hybrid Journal   (Followers: 5)
Journal of Civil Engineering and Construction Technology     Open Access   (Followers: 14)
Journal of Civil Engineering and Management     Open Access   (Followers: 8)
Journal of Computational Acoustics     Hybrid Journal   (Followers: 5)
Journal of Computing in Civil Engineering     Full-text available via subscription   (Followers: 21)
Journal of Construction Business and Management     Open Access   (Followers: 2)
Journal of Construction Engineering     Open Access   (Followers: 10)
Journal of Construction Engineering, Technology & Management     Full-text available via subscription   (Followers: 6)
Journal of Facilities Management     Hybrid Journal   (Followers: 3)
Journal of Green Building     Full-text available via subscription   (Followers: 10)
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: 5)
Journal of Structural Fire Engineering     Full-text available via subscription   (Followers: 4)
Journal of Sustainable Cement-Based Materials     Hybrid Journal  
Journal of Sustainable Design and Applied Research in Innovative Engineering of the Built Environment     Open Access   (Followers: 2)
Journal of the South African Institution of Civil Engineering     Open Access   (Followers: 2)
Journal of Transport and Land Use     Open Access   (Followers: 26)
Journal of Urban Technology and Sustainability     Open Access  
Landscape History     Hybrid Journal   (Followers: 15)
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  
PARC Pesquisa em Arquitetura e Construção     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 ALCONPAT     Open Access  
Revista de la Construcción     Open Access  
Revista de Urbanismo     Open Access   (Followers: 2)
Revista Hábitat Sustenable     Open Access  
Revista Ingenieria de Construcción     Open Access   (Followers: 1)
Revista INVI     Open Access  
RILEM Technical Letters     Open Access  
Room One Thousand     Open Access  
Ruang-Space: Jurnal Lingkungan Binaan (Journal of The Built Environment)     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: 8)
Steel Construction - Design and Research     Hybrid Journal   (Followers: 3)
Stroitel’stvo : Nauka i Obrazovanie     Open Access  
Structural Concrete     Hybrid Journal   (Followers: 4)
Structural Mechanics of Engineering Constructions and Buildings     Open Access   (Followers: 2)
Sustainable Buildings     Open Access   (Followers: 3)
Sustainable Cities and Society     Hybrid Journal   (Followers: 22)
Technology|Architecture + Design     Hybrid Journal  
Terrain.org : A Journal of the Built & Natural Environments     Free   (Followers: 3)
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: 2)
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: 7  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0219-4554 - ISSN (Online) 1793-6764
Published by World Scientific Homepage  [120 journals]
  • Vortex-Induced Force Model and Reliability Analysis of a Steel Box Girder
           with Projecting Slab in a Cable-Stayed Bridge

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      Authors: Peng Hu, Guangde Hu, Yan Han, Fei Zhang, Yongjian Tang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To study the vortex-induced force (VIF) model of a steel box girder with projecting slab, a cable-stayed bridge with a main span of 160[math]m was taken as the research object in this study. First, a computational fluid dynamics (CFD) numerical simulation method was used to calculate the amplitude characteristics of vortex-induced vibration (VIV) of the steel box girder with projecting slab, and the calculated results were compared with those of wind tunnel tests. Then, the time–history of VIF of the bridge girder was extracted based on the validated numerical simulation results, and a new mathematical model of VIF for the steel box girder with projecting slab was established according to the residual values between the reconstructed and target values. On such a basis, the steady VIV amplitude expression of the bridge girder was deduced according to the principle of the work done by the damping terms in the VIF model. Finally, the performance function of the maximum VIV amplitude was established with six random variables. Furthermore, the failure probability of VIV was calculated by the maximum entropy principle combined with the multiplicative dimensional reduction method, and the sensitivity of each random variable was analyzed as well. The results show that the lock-in region, VIV amplitudes and vibration frequency of the bridge girder calculated from the numerical simulations agree well with those from the wind tunnel tests, and the maximum amplitude occurs at the oncoming wind speed of 7.2[math]m/s. In addition to the most important fundamental-frequency component, there also exist double- and triple-frequency components in the time–history of VIF of the bridge girder, which implies the VIF exhibits certain nonlinear characteristics. According to the proposed expression of the steady VIV amplitude of the bridge girder, the steady amplitude decreases as the absolute value of parameter [math] increases, but it increases with the increase of the parameter [math]. The failure probability of VIV of the bridge girder is calculated to be 0.9616 based on the performance function with six random variables. Besides, it is found that the damping ratio [math] has great effects on the reliability of VIV, while the vertical bending frequency [math] exerts less effects.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-05-11T07:00:00Z
      DOI: 10.1142/S0219455422501395
       
  • Train-Induced Dynamic Behavior and Fatigue Analysis of Cable Hangers for a
           Tied-Arch Bridge Based on Vector Form Intrinsic Finite Element

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      Authors: Y. F. Duan, S. K. Wu, S. M. Wang, J. D. Yau, Y. Q. Ni, C. B. Yun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents train-induced dynamic response and fatigue damage analyses for the hangers of a tied-arch railway bridge. A train–bridge interaction analysis is carried out using the vector form intrinsic finite element method, through which the inertial force effect of the moving train can be effectively analyzed. The responses of the bridge deck and its hangers are investigated at resonant train speeds. Significantly larger stresses are observed on the shorter hangers near the arch anchorages, which is primarily caused by the first two anti-symmetrical vibration modes. The fatigue damage to the hangers is estimated using the Palmgren-Miner model (PMM) for linear fatigue damage accumulation and the continuum damage mechanics (CDM) method for nonlinear accumulation. The mean stress effect is considered in the S–N curve primarily by Smith–Watson–Topper equation in terms of the effective stress range with a zero-mean stress. Two probability distributions for train speed are considered for the current and future operating conditions with mean speeds of 220 and 300[math]km/h, respectively. This study found that the fatigue lives estimated by the nonlinear CDM are significantly shorter than those estimated by the linear PMM. It also found that the shortest hanger reflects the shortest fatigue life at the current operating speed, whereas the longer hanger near the third point of the bridge deck may have the shortest fatigue life at an increased speed in the future.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-05-09T07:00:00Z
      DOI: 10.1142/S021945542250136X
       
  • Effect of Control–Structure Interaction Using Torsional Servomotor for
           Active Tuned Mass Damper Control System

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      Authors: Xiao Yan, Zhao-Dong Xu, Qing-Xuan Shi, Jun Dai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The control–structure interaction (CSI) affects the performance and robustness of protective structures in active control system, and it is important to consider the CSI effect to achieve high performance in structural vibration control. In this paper, the electro-mechanical model of the torsional servomotor is derived by establishing dynamic voltage equilibrium equation. Three different active control models (non-CSI, reduced-order CSI, and higher-order CSI model) which considering different accuracy requirements of the electro-mechanical relationship are established to investigate the influence of the CSI on active tuned mass damper (ATMD) control system. The frequency- and time-domain responses of a three-story steel frame structure during different excitations are investigated, and as a comparison, the responses of the uncontrolled and tuned mass damper (TMD) control system are also studied. It can be concluded that the control performance of the active control system is reduced due to the CSI effect, especially at resonance frequency region of the structure (around 2.7[math]Hz, 8.2[math]Hz, and 13.2[math]Hz). The input voltage, velocity of the top floor, velocity of active mass, and higher-order of control forces have an important influence on the servomotor output control force. Furthermore, it can be found that, to achieve the same control effect, the required control voltage has been significantly increased due to the CSI effect.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-05-09T07:00:00Z
      DOI: 10.1142/S0219455422501425
       
  • The Influence of Aerodynamic Loads on Carbody Low-Frequency Hunting of
           High-Speed Trains

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      Authors: Jiacheng Wang, Liang Ling, Xin Ding, Kaiyun Wang, Wanming Zhai
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Low-frequency hunting problems of high-speed railway vehicles frequently occur due to the complex operating environment and degradation of wheel–rail contact conditions, which significantly affect the running safety and ride comfort of high-speed trains (HSTs). This paper presents a numerical investigation of the influence of aerodynamic loads on the carbody low-frequency hunting behaviors of HST. Considering the effect of aerodynamic loads, a multi-body system dynamics model for a HST train is formulated and applied to reproduce the carbody low-frequency hunting behavior. The influence of aerodynamic loads and wheel–rail contact conditions on the nonlinear stability of HST is analyzed. The range of aerodynamic coefficients of different aerodynamic loads which can stimulate the low-frequency hunting behavior of HST is proposed. The results show that the aerodynamic loads have a prominent effect on the nonlinear stability of HSTs. The low-frequency hunting motion of the HST tail car can be motivated by the lift airflow generated during service operation with a high traveling speed. The running stability of HSTs is more easily influenced by the aerodynamic loads when wheels are reprofiled.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-05-09T07:00:00Z
      DOI: 10.1142/S0219455422501450
       
  • Stochastic Optimization of Multiple Tuned Inerter Dampers for Mitigating
           Seismic Responses of Bridges with Friction Pendulum Systems

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      Authors: Yongkui Wen, Bo Hui
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Friction pendulum systems (FPSs) are increasingly being used for bridge seismic isolation, and the isolated response is generally achieved at the expense of inducing large bearing displacements. Setting up a tuned inerter damper (TID) is an approach for improving seismic performance. Nevertheless, the optimization and performance enhancement of multiple TIDs to mitigate the seismic responses of bridges isolated with the FPSs are limited. In this study, the stochastic optimization of multiple TIDs for controlling stochastically excited bridges with FPS bearings was pursued. By describing the hysteretic characteristics of the FPS using the Bouc–Wen model, augmented systems of the bridge model, FPS bearings, and TIDs were formulated and combined with the modeling of stochastic excitation as filtered Gaussian white noise. A stochastic optimization procedure of multiple TIDs for controlling the bridge response considering the nonlinearity of the FPS bearings is proposed and illustrated using examples of continuous bridges. The effects of FPS friction on the optimization and robustness of the TID parameters were identified. A parametric study was performed to determine the mechanism of TID performance enhancement depending on the number of TIDs, multiple modes of tuning, and inertance distribution. Numerical results indicate that the TIDs designed via stationary-stochastic-global (SSG) optimization significantly reduced the responses of the isolated bridge, and the performance was improved by increasing the TID number. Considering the multi-mode contributions to the transversal responses, the performance of spatially distributed TIDs can be substantially enhanced by adding the TID inertance as a design parameter.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-30T07:00:00Z
      DOI: 10.1142/S0219455422501371
       
  • Experimental and Numerical Study on the Influence of Plastic-Modified
           Concrete as Attenuation Layer on Explosion Effect

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      Authors: Wan-Li Wei, Ye-Qing Chen, Xin-Jian Ren, Jian-Hui Wang, Zhen-Qing Wang, Shang Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Reducing the damage of structures under stress wave is one of the popular and challenging issues in the field of protection engineering. In this study, the effect of plastic modified concrete as an attenuation layer on stress wave was investigated through large-scale explosion tests. The volume ratios of plastic particles used as replacement material were 2%, 4%, and 8%. Two explosions were used in each group to analyze the change of pressure under the plastic modified concrete as the attenuation layer. Experimental results showed that as low-impedance material, plastic particles can reduce the stress wave transmitted through the plastic modified concrete, and the elastic–plastic deformation of plastic increases energy consumption. Plastic modified concrete is more difficult to be compacted than loess attenuation layer. Thus, the clipping performance of the plastic modified concrete under the second explosion is better than that of the loess attenuation layer. The effect of plastic modified concrete on shortening the action time of stress wave is not obvious. Plastic modified concrete reduces damage by weakening the peak value of stress wave. The effects of explosive quantity, detonation distance, and plastic particle content on stress wave were studied through experiments and simulation. The propagation process of waves in the plastic modified concrete was studied via numerical simulation, and a fitting formula of wave cutting performance of plastic modified concrete was presented.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-27T07:00:00Z
      DOI: 10.1142/S0219455422501164
       
  • Seismic Performance Control of Tall Buildings Using a Novel Self-Centering
           Shear Wall System

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      Authors: Chen Xiong, Yousen Liu, Linlin Xie, Qiangsheng Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The reinforced concrete (RC) shear wall system is widely used as a lateral force resisting system in high-rise buildings. Nevertheless, the shear wall components of the system are vulnerable to destructive earthquakes, and the damage of shear wall components is a major hindrance for the seismic resilience of high-rise buildings. Therefore, a novel self-centering repairable (SCR) shear wall system is introduced in this study. Compared with the conventional RC shear wall system, the proposed SCR shear wall system exhibits good self-centering capability, and the energy dissipation element can be replaced easily after an earthquake. First, the configuration of the SCR shear wall is presented. Next, the design criteria used to achieve good self-centering and energy dissipation are discussed, and the finite element model used to simulate the SCR shear wall is presented. Finally, case studies are performed, and the numerical results indicate that the proposed SCR shear wall system exhibits better self-centering performance than the RC shear wall benchmark model. The outcomes of this study are expected to provide a useful reference for future experimental studies and practical applications of the presented SCR shear wall systems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-27T07:00:00Z
      DOI: 10.1142/S0219455422501310
       
  • Post-Buckling of Magneto-Electro-Elastic Porous Functionally Graded
           Cylindrical Shells with Geometric Imperfection

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      Authors: Hongyu Zhang, Haifeng Bai, Zhongyi Zuo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Cylindrical shell subjected to axial compression is very sensitive to the initial geometric imperfection. Even very small initial imperfection would significantly reduce the critical load. In this paper, the post-buckling behaviors of functionally graded (FG) porous magneto-electro-elastic (MEE) cylindrical shell with initial geometric imperfection is investigated by using the high-order shear deformation theory. The post-buckling equilibrium paths for different imperfection amplitudes are obtained by Galerkin’s method. Several numerical examples are presented to demonstrate the accuracy of the proposed model and reveal the effects of geometrical parameters, material properties, external magneto-electric loads on the post-buckling equilibrium path. In addition, the imperfection sensitivity of FG porous MEE cylindrical shells is also discussed.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-27T07:00:00Z
      DOI: 10.1142/S0219455422501383
       
  • Vortex-Induced Vibration Control of Long Stay Cables by Using
           Inerter-Based Dampers

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      Authors: Kun Xu, Junyan Song, Kaiming Bi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      With the increment of cable length, long stay cables are prone to experience high-mode vortex-induced vibrations (VIVs) at normal wind velocities, and the VIV-prone mode range also becomes wider. Existing dampers cannot supply sufficient damping for such a wide range of high-modes. Inerter-based dampers (IBDs), which take advantage of the two-terminal inertial device dubbed inerter, have been proved to have a better control performance than conventional dampers. However, existing studies on IBDs only focused on the first several cable modes, which cannot cover the wide range of VIV-prone modes of long stay cables. The high-mode and multi-mode VIV control by using IBDs is investigated in this study. The governing equations of the cable-IBD systems under VIV are first established. The control efficiency of the IBDs and the influence of optimum design strategies are compared. The use of two IBDs to further enhance the control efficiency is also discussed. The results show that a three-element IBD in this study is quite effective for high-mode and multi-mode VIV control of long stay cables. Moreover, the multi-mode control efficiency can be further improved through using two IBDs. The results in this study can guide the design of IBDs for VIV control of long stay cables.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-25T07:00:00Z
      DOI: 10.1142/S0219455422501358
       
  • An Iterative Method for Parameter Estimation of the Three-Parameter
           Weibull Distribution Based on a Small Sample Size with a Fixed Shape
           Parameter

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      Authors: Xiaoyu Yang, Liyang Xie, Bingfeng Zhao, Xiangwei Kong, Ningxiang Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The three-parameter Weibull distribution is popular in reliability analysis. However, in the context of a small sample size, the issue of parameter estimation of the three-parameter Weibull distribution is difficult to address. If only a small sample size is available, a reasonable method is to empirically determine the shape parameter, and the emphasis is placed on location parameter estimation. This paper presents a theoretical model to establish the relationship between the location parameter, the minimal sample value, and the sample size. Moreover, an iterative method is proposed to estimate the Weibull location parameter and scale parameter with an empirical value for the shape parameter. Compared with the maximum likelihood method (MLE), the Weibull plot with the sample correlation coefficient and TL-moment, the proposed method can more effectively estimate the parameters of the three-parameter Weibull distribution.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-22T07:00:00Z
      DOI: 10.1142/S0219455422501255
       
  • Development of Moving Force Identification for Simply Supported Bridges: A
           Comprehensive Review and Comparison

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      Authors: Hai-Chao Zhou, Hong-Nan Li, Dong-Hui Yang, Ting-Hua Yi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a comprehensive review of moving force identification on simply supported bridges. When a vehicle moves on a bridge deck, there is a dynamic interaction force between the vehicle and the bridge deck. This dynamic interaction force is crucial for the design and condition assessment of bridges. However, this interaction force cannot be directly measured. Therefore, the indirect measurement method based on the bridge response, namely, the moving force identification method, has become an important issue in evaluating bridge condition. This paper provides a comprehensive review of current research and development activities in bridge moving force identification. First, the development and application of moving force identification are introduced. Next, the theoretical methods of bridge moving force identification are presented. Then, the robustness and accuracy of moving time-varying force identification methods are numerically simulated and compared. Finally, the characteristics of these methods are summarized, which provides a basis for selecting the suitable identification methods under different conditions and prospects of the further development of moving force identification.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S0219455422300038
       
  • Advances in Variable Stiffness Vibration Isolator and its Application in
           Spacecraft

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      Authors: Feihu Liu, Dengyun Yu, Cong Wang, Guangyuan Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Variable stiffness vibration isolator (VSVI) can be switched between the low stiffness state and high stiffness state, respectively suitable for spacecraft requirement in cutting off the jitter transmitted from the bus to high accuracy payload and for avoiding long term adjustment during the process of attitude maneuver. For the advantage stated, the mechanism of VSVI is investigated for several types, considering the following factors: parallel manipulator with positive and negative stiffness components, structure with nonlinearity stiffness characteristics, smart materials or mechanisms, and maglev configuration. The design objectives of variable mechanisms are summarized into three indexes: adjustment range of stiffness, a lower limit of resonant frequency, and region with quasi-zero stiffness. Experimental studies for related isolators were presented, and the typical configuration or schematic diagram was shown under each index. As for the application of VSVI in spacecraft, research on the two significant problems, i.e. dynamic modeling and non-collocated control problem, is investigated for the design of control law of VSVI’s stiffness. Besides the complete description of spacecraft flexibility, variable stiffness characteristic that leads to a time-varying system and is easily coupled with the maneuvering process is worthy of more attention. Finally, challenges and future research are suggested for improving the performance in spacecraft application.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S021945542230004X
       
  • An Effective Crack Identification in Civil Infrastructure with IoT and
           Improved Convolutional Neural Network

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      Authors: S. Yoganand, S. Chithra
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Crack identification of buildings using the Internet of things (IoT) is done by continuously monitoring the building structures that provide an early indication of cracks in buildings. The established IoT system constantly gathers structural information using sensors and stores it on a cloud server. This paper presented an innovative machine learning crack identification methodology for detecting cracks using the sensor data. Initially, the collected sensor data is pre-processed by the cloud server using the data fusion process for further processing. Subsequently, effective damage sensitive features such as mode structure (MS) features such as damage signature, streamlined damage signature index, modal assurance criterion (MAC) and coordinate MAC, improved natural frequency (INF) features, and mode structure curvature (MSC) features with curvature damage factor are extracted from the pre-processed data to differentiate cracks easily. After features are extracted, the feature score-based random projection (FSRP) technique is utilized for dimensionality reduction. Finally, hybridization of improved convolutional neural network with modified whale optimization (ICNN-MWO) detects the cracks in the civil structure utilizing the selected features. These effective classification results might alert the user when a high severity or damage is likely to occur. The implementation platform used in this work is PYTHON. The experimental outcomes of the presented technique proved that the presented work is significantly better in terms of various effective performance measures like accuracy (99.93%), mean squared error (3%), precision (99.91%), recall (99.90%), and F-measure (99.9%). The experimental results of the presented methodology provide improved performance than the existing crack identification techniques.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S0219455422501280
       
  • A New Formula for Predicting Lateral Distortional Buckling Strength of
           I-Beams Subjected to Different Loading Conditions

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      Authors: Alexandre Rossi, Mahmoud Hosseinpour, Carlos Humberto Martins, Yasser Sharifi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Lateral distortional buckling (LDB) mode has been investigated as one of the failure modes in steel I-beams. The LDB mode in such beams is known by simultaneous lateral deflection, twist, and cross-sectional change due to web distortion. However, many studies have been conducted to investigate the behavior of this failure mode; so far, no formula has been found to calculate the ultimate LDB resistance of I-beams, which also takes into account the effect of different loading conditions. Consequently, in the current paper, by conducting an extensive parametric study, it was tried to investigate the effect of all main parameters as well as the effect of different loading conditions on the ultimate LDB resistance of I-shaped beams. Then, based on the provided database, the artificial neural network (ANN) method was employed, and based on it, a high-precision formulation was proposed to predict the ultimate LDB strength of steel I-beams. In addition to the ANN method, a regression-based formula was also developed as a classical method to examine the differences between the two methods. Finally, the proposed formulas were compared with other existing formulas for estimating the LDB strength. The results showed that the proposed formula based on ANN not only presents a reasonable accuracy compared to the existing formulations but also can be used by engineers as practical equations in the design of I-beams.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S0219455422501292
       
  • Study on the Nonlinear Dynamic Characteristics of Spherical Rubber
           

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      Authors: Hao Li, Chengliang Yang, Shaoxin Wang, Ping Su, Youqiang Zhu, Xingyun Zhang, Zenghui Peng, Quanquan Mu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study aims to elucidate the nonlinear characteristics (dynamic stiffness and damping) of a thin-walled hallowed spherical rubber isolator subjected to harmonic excitations using harmonic balance method (HBM). Firstly, harmonic excitation experiments with different loads and different acceleration levels were carried out to test the softening effect of the spherical rubber isolator. The dependence of the dynamic stiffness and damping of the spherical rubber isolator on the displacement amplitude was established. Secondly, the [math]th harmonic of the experimental time signal was extracted, and the nonlinear contribution of the second and third harmonics to the experimental results was verified. Finally, the simulations were performed and the results were in line with the experimental results. Our study identifies that the nonlinear model is feasible to predict the vibration characteristic of the thin-walled hallowed spherical rubber isolation systems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S0219455422501334
       
  • Structural Damage Recognition Based on Filtered Feature Selection and
           Convolutional Neural Network

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      Authors: Zihan Jin, Shuai Teng, Jiqiao Zhang, Gongfa Chen, Fangsen Cui
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes a structural damage recognition method based on the filtered feature selection (FFS) and the convolutional neural network (CNN). The FFS usually provides a better sample feature input for a CNN, avoiding the problem that the CNN is prone to over-fitting for the data containing a large amount of invalid feature information. To demonstrate the efficiency and accuracy of the method, a steel frame structure is investigated. The acceleration signals under three different measures (Chi-square test, F test and Mutual information method) of the FFS are studied, along with their influence on the CNN recognition accuracy, network training time and feature dimension. Studies have shown that the Chi-square test has the best effect over the other two measures in terms of efficiency and accuracy. The results of numerical simulations and vibration experiments show that the method has achieved good results in terms of recognition accuracy and training time, and it can significantly reduce the feature dimension while ensuring the accuracy of the CNN recognition.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-20T07:00:00Z
      DOI: 10.1142/S0219455422501346
       
  • Experimental Study of the Aerodynamic Characteristics of a Suspended
           Monorail Vehicle-Bridge System Under Crosswinds

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      Authors: Yunfeng Zou, Zhipeng Liu, Kang Shi, Jun Song, Xuhui He, Qingkuan Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Using wind tunnel tests, the aerodynamic characteristics of a suspended monorail transport (SMT) are systematically investigated under crosswinds for the first time. Two practical vehicle–bridge combination forms (single-line and double-line) are considered. As a contrast, single vehicle and bridge models are also studied to further reveal their aerodynamic characteristics. The mean and root mean square (RMS) wind pressure coefficients, aerodynamic coefficients and power spectrum density (PSD) distributions are used to numerically investigate the effects. The paper confirms that: (1) the mean wind pressure coefficients of the single vehicle and bridge models are close to unity at the center point of the windward side and gradually decrease from the center point to both sides. The maximum value of the RMS wind pressure coefficients mainly occurs at the top or bottom surface of the testing models due to the effect of vortex shedding; (2) the aerodynamic coefficients and the mean and RMS wind pressure coefficients are significantly increased for both the vehicle and bridge models when considering the aerodynamic coupling effects; (3) the aerodynamic characteristics of the bridge can be significantly affected by the location of the running vehicle, but the fluid flow can maintain relative stability during the meeting of the two vehicles.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-19T07:00:00Z
      DOI: 10.1142/S0219455422410073
       
  • Effects of High-Speed Trains on Trucks Running on a Road–Rail
           Dual-Use Bridge Under Crosswind

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      Authors: Yunfeng Zou, Peng Yue, Kang Shi, Fanrong Xue, Xuhui He, Qingkuan Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The road–rail dual-use bridge can simultaneously meet the requirements of both the highway and railway transportation owing to its unique bridge type, which makes it environmentally friendly and cost-effective when compared to independent railway and road bridges. This study establishes a dynamic model of a wind-road vehicle–bridge system considering the aerodynamic sheltering effect of trains based on the coupling vibration method of wind-road vehicle–bridge systems. A container truck and a CRH2 high-speed train are considered as the research objectives, and a series of wind tunnel tests are conducted for the train and truck running simultaneously on a road–rail dual-use bridge to determine the effect of the aerodynamic interference of trains on the aerodynamic characteristics and dynamic behavior of vehicles under crosswinds. The entire process of driving the truck through the cable-stayed bridge under crosswinds and the interference of stationary trains is subsequently simulated to generate the time histories of the dynamic displacements of the truck. Consequently, the effect of the stationary trains is separately compared at different locations, such as on the track of the bridge deck and on the truck placed upwind and downwind. Furthermore, the interference effect of stationary trains on the truck placed upwind and downwind is analyzed corresponding to different wind yaw angles. The results demonstrate that the presence of trains on the bridge significantly affects the aerodynamic coefficients and dynamic responses of the truck placed downwind when compared to the truck placed upwind. Additionally, the presence of the trains on the bridge deck has a different effect on the aerodynamic coefficients and dynamic responses of the truck placed downwind. The effect of the trains on the truck at different wind yaw angles presents different patterns of change for different locations of the trains on the bridge deck.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-18T07:00:00Z
      DOI: 10.1142/S021945542250122X
       
  • Joint Estimation of Multi-Scale Structural Responses and Unknown Loadings
           Based on Modal Kalman Filter Without Using Collocated Acceleration
           Observations

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      Authors: Jia He, Baichuan Deng, Xugang Hua, Xiaoxiong Zhang, Ou Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      It has been proved that the usage of multi-type observations including global and local information for structural health monitoring (SHM) outperforms that of solo-type measurement. Kalman filter (KF) is a simple but powerful tool for the online state estimation. However, external force is required for the classic KF. Moreover, direct implementation of KF in time domain may be time consuming especially for large structures with many degrees-of-freedoms (DOFs) involved. From these points of view, the idea of modal Kalman filter (MKF) is introduced. An MKF-based approach is then proposed for joint estimation of multi-scale responses and unknown loadings with data fusion of multi-type observations. By using a projection matrix and the selected several modes, a modified observation equation in modal domain is derived. Limited multi-type measurements are fused together for online estimating multi-scale responses of structure at its critical locations. The unknown excitation is simultaneously identified by least squares estimation (LSE). The drift problem of the real time estimation of structural responses and unknown loads is avoided. The effectiveness of the proposed approach is numerically demonstrated via several examples. Results show that the proposed approach is capable of satisfactorily estimating the unmeasured multi-scale responses and identifying the unknown loadings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-18T07:00:00Z
      DOI: 10.1142/S0219455422501322
       
  • Dynamic Interaction Analysis of High-Speed Maglev Train and Guideway with
           a Control Loop Failure

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      Authors: Huoyue Xiang, Xiangfu Tian, Yongle Li, Min Zeng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The fault of a control loop can occur when a high-speed maglev train is running on guideways, which will affect the dynamic responses of the maglev train and guideway and is one of the controlling cases in the design of guideway functional parts. To study the dynamic response of the vehicle and guideway when a control loop failure occurs, first, a spatial coupling vibration model, which includes the three-dimensional (3D) maglev trains, guideways, piers and electromagnetic force based on the proportional-derivative (PD) controller, is proposed, and the electromagnetic force model for a control loop failure is presented. Second, the effectiveness of the coupling vibration model is verified based on the measured results of the Shanghai maglev line (SML). Finally, the dynamic responses of maglev train and guideway are discussed under a suspension magnet or guidance magnet with a control loop failure, and the influences of the location of the fault, the weight of the vehicle and the preload of the guidance system are analyzed. The most disadvantageous load value acting on the functional parts in case of magnet failure is obtained. The results show that the dynamic responses of the maglev train with a control loop failure will vary due to the location of the fault on trains and guideways, the weight of vehicle and the lateral preload. Although a control loop failure has little influence on the dynamic response of the guideway, the suspension force or guidance force on guideway will increase suddenly, and this sudden force is far larger than the vehicle static load or lateral preload of guidance magnets.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-13T07:00:00Z
      DOI: 10.1142/S0219455422410127
       
  • A Method Based on Riccati Equation for the Vibration Analysis of Rods with
           Variable Cross-Sections

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      Authors: Yaşar Pala, Çağlar Kahya
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, the longitudinal vibration of rods with variable cross-sections is studied. For the analytical solution of the problem, a new analytical method based on a recently developed method on the Riccati differential equation is utilized. The governing equation is reduced to Hill’s type second-order ordinary differential equation. The transformed equations can readily be solved analytically for various cases according to the method. Seven cases have been considered, and the frequency equations for each case have been obtained. According to the method developed, the problem is solved in the simplest way. By using the present method, the reader can readily decide whether the problem is solved analytically or numerically. The present method can solve the problem of longitudinal vibration of rods having cross-sections of arbitrary shape. Finally, the method is also applied to the longitudinal vibration of stepped rods. Mode shapes are plotted for special values.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-13T07:00:00Z
      DOI: 10.1142/S0219455422501231
       
  • Forced Vibration Analysis of Uniform and Stepped Circular Cylindrical
           Shells with General Boundary Conditions

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      Authors: Cong Gao, Fuzhen Pang, Haichao Li, Xueren Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, the experimental and Jacobi–Ritz method (JRM) have been adopted to analyze the forced vibration analysis of uniform and stepped circular cylindrical shells with general boundary conditions. The simply supported cylindrical shell at both ends is taken as an experimental model, and the free, steady and transient vibration characteristics of structures under hammer and fixed exciter are recorded. The results show that the results of JRM are in sensible agreement with those in experiment. In addition, the results for various boundary conditions, structural parameter are also presented. On this basis, the Newmark-[math] integration method is adopted to realize the time domain solutions for transient vibration response, and the frequency domain results can be obtained by using Fourier transformations from time domain results. Finally, the line spectrum vibration response results of the structure are presented under the random excitation load, and the research can supply technical support for the vibration control of cylindrical shell structure.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-13T07:00:00Z
      DOI: 10.1142/S0219455422501267
       
  • Structural–Acoustic Response Analysis of Variable Stiffness Laminates
           with Inherent Material Damping

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      Authors: Vijay Gunasekaran, Saurav Gulhane, Somya Gupta, Jeyaraj Pitchaimani, Vasudevan Rajamohan, Ganapathi Manickam
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Sound radiation and transmission loss characteristics of variable stiffness composite plate reinforced with the curvilinear fibers are investigated numerically. The formulation is developed using higher-order shear flexible finite element model combined with Helmholtz wave equation. The governing equations obtained using Hamilton’s approach are further solved through the modal super position method to analyze the vibration response under steady state excitation. The inherent material damping of the laminate is accounted through the modal damping calculated using the modal strain energy approach. The acoustic pressure of the variable stiffness laminates is estimated using the Raleigh integral. Subsequently, acoustic response characteristics such as acoustic power level, radiation efficiency, directivity pattern, and transmission loss from the laminates are predicted using the estimated sound pressure for various forcing frequencies. A parametric study covering a wide range of design variables including center and edge fiber angles, lamination scheme, thickness ratio, and boundary conditions on the acoustic sound behavior arising from the vibration of curvilinear fiber composite plate is detailed. This study reveals that the acoustic response of the curvilinear fiber composite plate is significantly influenced by the curvilinear fiber angles at the center/edge fiber angle of the layers. It is hoped that the results obtained here will be useful for designers in developing structures with desired acoustic response characteristics.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-13T07:00:00Z
      DOI: 10.1142/S0219455422501279
       
  • Straight-Beam Approach for Analyzing Lateral Buckling of Thin-Walled
           Curved I-Beams

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      Authors: Y. B. Yang, P. X. Jiang, Y. Z. Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The straight-beam approach is a simple and efficient means for analyzing the buckling of curved beams. Although previous researchers showed that the straight-beam approach is capable of simulating the lateral buckling of solid curved beams, the warping effect had been neglected and thus its practical application in engineering was limited. In this study, thin-walled curved I-beams will be dealt with by assuming the warping degrees of freedom (DOFs) to be identical at the common node for non-aligned connected elements. One feature of the present formulation is that the moments induced by initial nodal moments undergoing out-of-plane rotations are duly considered in the geometric stiffness matrix, while the compatibility and equilibrium are enforced for angled joints at the deformed position. With high computational efficiency, the present approach obtains buckling loads that agree well with the theoretical curved-beam solutions or the ones obtained by ABAQUS using shell elements. Compared with the modern curved-beam elements, the straight-beam element is locking free, invariant and simple in formulation, since the effect of curvature is not involved in global assembly.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-13T07:00:00Z
      DOI: 10.1142/S021945542271002X
       
  • A Comparative Study on the Behavior of Ride Quality Due to Deflated State
           of Air Spring using Different Properties of Hyperelastic Material

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      Authors: Vikas Tiwari, Satish C. Sharma, S. P. Harsha
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Elastomers are widely used in various engineering applications due to their huge elasticity and good dynamic behavior. One of the elastomeric elements is rubber blocks, which are used in many applications, such as vibration isolators, bumpers, shock absorbers, dampers, etc. In this research, the impact on the ride index due to the deflated state of the air spring with various kinds of hyperelastic materials is analyzed by the finite element method. The stress–energy function of rubber materials is first diagnosed, and Poisson’s ratio defined the volumetric terms. The rubber isolator’s stress is studied based on the finite element model, and the structure is improved. It is observed that for the deflated state of the air spring, laminated rubber isolation diminishes the muscular amount of structural responses compared to the conventional rubber base structures, and improves the ride comfort. This study would assist in doing finite element analysis of the secondary suspension system and other vibration-damping components.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-11T07:00:00Z
      DOI: 10.1142/S0219455422410012
       
  • Sensitivity and Reliability Analyses in to Actively Controlled Structures
           Under Earthquake

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      Authors: Saeed Hosseinaei, Mohammad Reza Ghasemi, Sadegh Etedali, Tommy H. T. Chan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study aims for a probabilistic assessment of active seismic control of structures in the presence of uncertainties of the structural model and the stochastic model of the ground acceleration. First, sensitivity analyses based on the Borgonovo sensitivity index are conducted to measure the effect of uncertainty sources on the maximum and root mean square (RMS) of the main structural responses in different seismic hazard regions. Then, the reliability analyses are conducted using Monte Carlo simulation (MCS) and importance sampling (IS) methods to the estimation of failure probabilities and reliability indices of the structures in different seismic hazard regions, force capacity of actuators, and seismic performance levels. Numerical studies carried out on a 10-story structure show that the uncertainties in peak ground acceleration (PGA) and story stiffness have the most effects on the seismic responses of the structure. The effect of the considered uncertainties is negligible on the maximum demand control force. The results also show that equipping the structure with an active control system results in a significant reduction in the failure probabilities of the structure. The target reliability index for the uncontrolled structure in life safety seismic performance level may not be satisfied in high and very high seismic hazard regions, it can however be easily dealt with, using the proposed technique, in the corresponding controlled structures. By increasing the control force capacity, an increment is observed in the reliability index. A high and suitable reliability index is given for both controlled and uncontrolled in the collapse prevention seismic performance level.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-09T07:00:00Z
      DOI: 10.1142/S0219455422501243
       
  • Advances in Active Control of Wind-Induced Vibration of Long-Span
           Suspension Bridges

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      Authors: Zengwei Guo, Sen Lin, Qian Ni
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper reviews various active control measures used for controlling the wind-induced vibration, which is a problem of great concern for long-span suspension bridges. Firstly, a brief discussion of passive control measures and their limitations is presented. Then, the development of active aerodynamic control and active mechanical control is comprehensively reviewed to present the characteristics and limitations of numerous control devices with emphasis on the control surfaces adopted for active aerodynamic control. Particularly, the existing challenges and suggestions for future studies are proposed for various countermeasures, especially for the control surfaces used in active control. It is expected that the information provided in this article will facilitate further research in the area of vibration control for long-span suspension bridges under various wind conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-08T07:00:00Z
      DOI: 10.1142/S0219455422300026
       
  • Dynamic Fracture Analysis of Natural Gas Pipelines Based on a Cohesive
           Zone Model

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      Authors: Yi Liao, Changlei Liu, Kexi Liao, Jiaxin Jia, Liang Ge, Meizhen Xiang, Jun Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Fracture research of natural gas pipelines with cracks is an important part of pipeline integrity evaluation. Based on the cohesive zone model (CZM), a numerical analysis is conducted of the dynamic fracture of X80 steel pipelines under explosion load. The factors considered include the crack propagation length, crack propagation velocity, dynamic crack tip opening angle (CTOA) and gas pressure. The results show that the whole cracking process can be divided into three stages: rapid cracking, stable propagation, and deceleration and stop cracking. When in the rapid cracking stage, the axial cracking of the pipeline is dominant. However, in the stable propagation stage, lateral expansion plays a more significant role. Besides, there exist upper limits on the length and velocity of crack propagation. In addition, it is also found that the time for the inflection point of rapid cracking and stable propagation is later than that to reach the velocity peak. The dynamic CTOA decreases with axial crack propagation, and the steady-state value of the CTOA is positively correlated with the load. The high-pressure gas escapes from the pipeline along the crack, resulting in the increase of air pressure outside the pipeline. Moreover, the peak pressure outside the pipeline is approximately linear its the initial crack length. The present research on the dynamic fracture mechanics behavior of the pipeline provides a necessary supplement for the test.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-08T07:00:00Z
      DOI: 10.1142/S0219455422501188
       
  • Development of the Dynamic Response of Curved Bridge Deck Pavement Under
           Vehicle–Bridge Interactions

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      Authors: Xia Zhang, Enli Chen, Lingyun Li, Chundi Si
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Curved bridge is commonly used in highway viaducts and overpass, on which deck pavement plays a crucial role in dispersing wheel load and providing level driving surface. Due to the influence of geometric nonlinearity of curved bridge and vehicle–bridge coupling vibration, curved bridge deck pavement (BDP) is subjected to a complex mechanical state. To study the dynamic response of the curved BDP under complex vehicle–bridge interaction (VBI) condition, this paper proposes an original dynamic analysis scheme. The BDP and bridge structure are simulated by the finite element method and the vehicle is simulated as a multi-body system (MBS); together they are integrated into a coupled system model. The numerical results are consistent with the experimental data. The dynamic responses of the proposed scheme are about 10–20% larger than those of moving constant forces, which indicates that the vehicle–bridge coupling vibration should be considered in the dynamic analysis of BDP. The parametric study shows that the vehicle weight can aggravate the response of the BDP; however, the effect of the vehicle speed on the deck pavement response and impact factor is not obvious. As road roughness classification and tire stiffness increase, the dynamic curve fluctuation of BDP is more obvious and the amplitude is larger. Through parameter sensitivity analysis, it can be concluded that vehicle weight has the greatest effect on the dynamic behavior of BDP, followed by vehicle speed and roughness, and tire stiffness has the least impact.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-07T07:00:00Z
      DOI: 10.1142/S0219455422410036
       
  • Running Safety of High-Speed Railway Train on Bridge During Earthquake
           Considering Uncertainty Parameters of Bridge

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      Authors: Xiang Liu, Lizhong Jiang, Ping Xiang, Yulin Feng, Zhipeng Lai, Wen Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      China’s railway network is wide, and some of them cross the seismic zone, and the ratio of high-speed railway (HSR) bridges is high. Therefore, the safety of trains on the bridge may be endangered in the event of an earthquake. Because the response of track–bridge system is sensitive to the randomness of bridge structural parameters during the earthquake, while the train wheelset is directly in contact with the track system, the running safety of train (RST) may be also sensitive to the randomness of structural parameters. In this paper, the model of train–bridge coupled system (TBCS) under earthquake was established, and the accuracy of the model was verified by test results. To efficiently calculate the safety performance of trains considering the randomness of structural parameters, the point estimation method (PEM) was used in this paper, and the applicability of PEM was proved by comparing with the calculation results of Monte Carlo simulation (MCS). Then, PEM was used to discuss the running safety performance of trains under different ground motion (GM) intensities, different train speeds, and different pier heights. Finally, based on the maximum probability, the GM intensity threshold of a bridge based on running safety is determined.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-07T07:00:00Z
      DOI: 10.1142/S0219455422410085
       
  • A Probabilistic Model for the Amplification of the Vibration Response of
           Railway Bridges Due to Random Track Unevenness in High-Speed Traffic

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      Authors: Patrick Salcher, Christoph Adam, Paul König
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In combination with the moving train, track irregularities have a significant influence on the structural response of railway bridges. Compared to the ideal case of perfect track geometry without any irregularities, an amplification of the response is observed. This paper proposes a probabilistic model to predict this dynamic response amplification of railway bridges due to random track irregularities when subjected to high-speed trains. The developed regression model, based on a parametric numerical study, provides the mean and standard deviation of the dynamic response amplification separately for bridge deflection and acceleration, since large differences are found for these vibration variables. Depending on the span, mass, fundamental frequency, and damping coefficient of simply supported bridges, dynamic response amplification statistics are approximated for a range of train speeds and different track qualities. The proposed model estimates the dynamic response amplification due to random track irregularities at predefined exceedance probabilities, and a customized amplification factor is determined that is consistent with the semi-probabilistic safety concept used in structural design. An application example shows the superiority of this model compared to the commonly used code-based approach.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-07T07:00:00Z
      DOI: 10.1142/S0219455422410097
       
  • Buckling Analysis of Cylindrical Shells with Variable Thickness Subjected
           to Non-Uniform Axial Compression by Establishing a Novel Quadratic
           Perturbation Technique

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      Authors: Licai Yang, Tian Qiu, Yuanyuan Dong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper analytically studies the buckling of a cylindrical shell having varying thickness under non-uniform axial compressive loads for the first time, which widely exists in engineering practice. A novel quadratic perturbation technique is developed to establish general buckling load formulas for the shell. This method overcomes the difficulties of traditional energy methods in solving high order determinants and deriving direct expressions for buckling loads when shell thickness and axial load are unknown. Applying presented formulas, various shell thicknesses and axial loads are analyzed, and a series of new results for buckling loads are obtained and validated. Even for classical cosine thickness variation under uniform axial compression, we also give general conclusions compared with Koiter’s results by the energy method. The effects of thickness variations and load distribution parameters on buckling loads are analyzed in detail. The presented study in this paper fills the gap and establishes a foundation of buckling analysis for non-uniformly loading cylindrical shells with variable thickness. Certainly, the established formulas are general and available for buckling resistance capacity evaluation for the shells under all circumstances involving thickness variations or/and non-uniform axial compressive loads.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-07T07:00:00Z
      DOI: 10.1142/S0219455422501206
       
  • Closed-Form Demonstration and Shake Table Verification of Damping Effect
           on the Seismic Energy

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      Authors: Ahmet Güllü, Ercan Yüksel, Elif Altintaş
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper discusses closed-form demonstrations of the damping effect for a basic mass, spring, and damper (MSD) and a single degree of freedom (SDOF) system that are exposed to harmonic loading. Initially, the energy balance equations of the systems were solved in closed form by considering the damping ratio and loading frequency. Verification of the solutions obtained for SDOF systems is achieved by shake table tests. Based on the analytical and experimental results, it was found that the damping effect is highly related to the ratio of loading frequency to the natural vibrational frequency of the system. For the lower and higher values of the ratio, damping is found to be almost ineffective. However, the effect becomes substantial when the ratio reaches unity i.e. at the resonant frequency. Damping has a reverse relation with seismic energy at the dominant frequency. In contrast, the relation is proportional in the vicinity of resonance frequencies. Hence, considering the damping as a parameter for the energy-based design of structures is suggested.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-07T07:00:00Z
      DOI: 10.1142/S0219455422501218
       
  • Erratum: Time-Varying Transmissibility Analysis of Vehicle–Bridge
           Interaction Systems with Application to Bridge-Friendly Vehicles

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      Authors: Ke Lin, Chin An Tan, Chengqiang Ge, Huancai Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.

      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-06T07:00:00Z
      DOI: 10.1142/S0219455422920018
       
  • Seismic Performance Assessment of a Single-Layer Spherical Lattice Shell
           Structure with Multifunctional Friction Pendulum Bearings

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      Authors: Zhuang Peng, Wei Luyao, Han Miao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The dynamic responses of spatial lattice shell structures with friction pendulum bearings (FPBs) under multidimensional seismic excitations are complex. In addition, FPBs may experience uplift and separation of the bearing components owing to excessive displacements. In this study, a novel multifunctional FPB (MFPB) with a multi-defense system was developed, and its effectiveness in reducing and controlling the seismic responses of spherical lattice shell structures was evaluated. The proposed MFPB comprises an FPB, superelastic shape-memory alloy cables, and sleeve restrainers. A mechanical model of the MFPB was established, and its isolation and control behaviors were investigated through numerical simulations. Furthermore, the main characteristics and advantages of the isolation system were analyzed. Subsequently, the MFPB system was applied to a single-layer spherical lattice shell structure with surrounding columns. A computational model of the controlled structure was developed using the OpenSees software. Finally, nonlinear time history analyzes were conducted to analyze the seismic performance of controlled and uncontrolled lattice shells. The results demonstrate that the MFPB isolation system can effectively control the structural responses of isolated spatial lattice shell structures under horizontal and vertical seismic excitations and improve their seismic resilience.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-04T07:00:00Z
      DOI: 10.1142/S021945542250119X
       
  • Energy Absorption Characteristics and Functional Gradient Optimization of
           a Hybrid Honeycomb

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      Authors: Yuan Gao, Huaiwei Huang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Metastructures are extensively used in aerospace engineering. In the present work, a high-strength structure was designed based on a reentrant hexagonal honeycomb (RHH) by topology optimization. To generate a negative Poisson’s ratio (NPR) effect, topologically optimized cells were alternately arranged with RHH cells to obtain a hybrid hexagonal honeycomb (HHH). In comparison with other NPR structures, this structure had superior energy absorption characteristics. In addition, the mechanical properties and deformation behavior of this structure were analyzed. Finally, single, double, and triple functional gradients were introduced into the HHH. It was found that the introduction of functional gradients improved the energy absorption capacity of the structure, and that the energy absorption capacity increased with the increase in the number of functional gradients.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-04-01T07:00:00Z
      DOI: 10.1142/S0219455422501176
       
  • Recursive Predictive Optimal Control Algorithm for Real-time Hybrid
           Simulation of Vehicle–Bridge Coupling System

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      Authors: Huimeng Zhou, Bo Zhang, Xiaoyun Shao, Yingpeng Tian, Chen Zeng, Wei Guo, Tao Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Real-time hybrid simulation (RTHS) is recently applied to study the vibration of the vehicle–bridge coupling system, where bridges and the vehicle are the numerical and experimental substructures respectively. Inevitable time delay of the boundary loading imposed to the experimental substructure will greatly affect the accuracy and stability of RTHS. To minimize the time delay effects, this paper proposes a recursive prediction optimal (RPO) compensator based on optimal control and recursive least squares. The numerical simulation of the RTHS of the vehicle–bridge coupling system is conducted using MATLAB/Simulink. The performance of the RPO method is compared with three traditional time delay compensation methods (i.e. the polynomial extrapolation (NI), the inverse compensation (IC) and the derivative feedforward (DF)) through both open-loop and RTHS simulations. The RPO method shows the best compensation performance in the frequency range up to 20[math]Hz.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-30T07:00:00Z
      DOI: 10.1142/S0219455422410115
       
  • Transition Waves in One-Dimensional Periodic Bistable Mass-Spring Chains

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      Authors: Lin Chen, Ao Xu, Jia Lou, Huaping Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The propagation of transition waves in multi-stable mechanical systems can be effectively harnessed in various fields, such as mechanical signal communication, mechanical diodes, and energy absorption. In this work, the propagation of transition waves in a one-dimensional (1D) bistable mass-spring chain is systematically studied. The underlying physical mechanism for the formation and propagation of transition waves is clarified, and the influences of some crucial factors, such as the pumped momentum, stiffness of the connecting springs, viscous damping, number of masses, and asymmetry of the double-well potential, on the propagation of transition waves are discussed in detail. As a result, the parameter space for achieving the robust propagation of transition waves through the whole chain is presented. This study is expected to be beneficial for the control of transition waves and design of novel devices used for mechanical signal transmission.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-30T07:00:00Z
      DOI: 10.1142/S0219455422501000
       
  • Free Vibration, Buckling and Dynamical Stability of Timoshenko
           Micro/Nano-Beam Supported on Winkler-Pasternak Foundation Under a Follower
           Axial Load

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      Authors: Zewei Li, Baichuan Lin, Bo Chen, Xiang Zhao, Yinghui Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Axially loaded micro/nano-beams supported on foundations are extensively applied in micro/nano-electro-mechanical systems. This paper deals with the problems of free vibration, buckling and dynamical stability of Timoshenko micro/nano-beam supported on Winkler–Pasternak foundation subjected to a follower axial periodic load. Based on Hamilton’s principle, the governing equations of the system are derived in conjunction with nonlocal strain gradient and Timoshenko theory. The transition parameter is introduced to describe the follower direction of axial load during the deformation of the micro/nano-beam. Employing the weighted residual method, the variational consistency boundary conditions (BCs) can be derived according to the governing equations. Using differential quadrature method (DQM), the governing equations are discretized and numerical solutions of the natural frequencies, critical buckling load and instability region are obtained. Numerical examples are performed to verify present solutions by those available in the literature. Significant effects of the transition parameter and variational consistency BCs are revealed on the free vibration, buckling and dynamical stability of the axially loaded micro/nano-beam. The present analysis is of significance to axially-loaded micro/nano-beam mechanical system, especially for determination of the direction of follower axial force.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-30T07:00:00Z
      DOI: 10.1142/S0219455422501139
       
  • Periods and Mode Shapes for Uniform Shear Wall Buildings: Importance of
           Selecting the Appropriate Dynamic Behavior

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      Authors: Mohamed Chennit, Ali Ahmed-Chaouch, Messaoud Saidani, Abdelkrim Bourzam
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The distribution of seismic loading to each storey of a building depends on a number of factors, mainly on the periods, mode shapes and modal participation. The estimation of these dynamic characteristics is essential in analyzing the seismic response of multi-storey buildings. Based on a rigorous dynamic analytical model of the building, this research provides a novel database of vibration modes of multi-storey buildings with reinforced concrete (RC) shear walls. The Stodola–Vianello iterative method was used to determine these. The first modes of vibration, cumulating a modal mass participation ratio (MMPR) greater than 90%, are summarized and presented in a table form. The results are equally valid for uniform buildings with masonry infill walls. The research has highlighted that the eigenvectors are independent of the values of the mass and the mechanical characteristics of the structure (the modulus of elasticity, the moment of inertia and height) but also on the variation of these characteristics over the height of the building. Consequently, for shear wall buildings with identical storeys, the eigenvectors, the MMPRs and the modal participation factors are accurately determined for this type of structure. The significance of the research consists of providing a table that engineers and researcher scan easily use to determine the dynamic characteristics of the building, thus avoiding repetition of the calculations relating to this type of buildings. The study has also highlighted the importance of selecting the appropriate dynamic behavior of the structure for seismic design.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-30T07:00:00Z
      DOI: 10.1142/S0219455422501140
       
  • Nonlinear Analysis on Flow-Induced Vibration of Single-Walled Carbon
           Nanotubes Employing Analytical Methods

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      Authors: S. E. Ghasemi, Sina Gouran
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this research, the vibration and frequency of single-walled carbon nanotubes (SWCNTs) with conveyance a fluid flow are assessed analytically. The nanotube is imbedded in a Pasternak foundation and the nonlocal beam model is utilized to study on flow-induced vibration of the SWCNT. The differential transform method and variation iteration scheme have been employed to solve the nonlinear differential equation of the problem. The validity of proposed approaches is evaluated by comparing with numerical findings obtained using Keller Box method (KBM). The effects of main parameters including velocity of flow, nonlinear amplitude, nonlocal parameter as well as axial tensions on variation of the SWCNT’s frequency are examined. The outcomes indicate that increment of the nonlocal parameter leads to enhancement in variation of frequency. Also, the frequency variation of the SWCNT increases by elevating the axial tension.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-30T07:00:00Z
      DOI: 10.1142/S0219455422501152
       
  • A Novel Rigid Finite Element Formulation for Dynamic Analysis of Flexible
           Plates

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      Authors: Ali Kermanian, Afshin Taghvaeipour, Ali Kamali E.
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper introduces a new rigid finite element method (RFEM) formulation for dynamic analysis of plates. In RFEM, a flexible body is divided into several rigid elements which are interconnected by spring and damping elements. Mainly, RFEM has been used to model systems with beam-like slender components, such as ropes and cables, and few RFEM formulations were developed to model plates and shells. In this study however, by means of the Timoshenko beam theory and cuboid rigid elements, a novel RFEM formulation is developed to model flexible flat plates with generic geometries of the surface, considering large deformation. For this purpose, an RFEM formulation is presented for straight beams with rectangular cross-section by means of the Timoshenko beam theory. Next, this formulation is expanded to model flexible rectangular plates with uniform thickness and then, it is elaborated on how to model non-rectangular plates with uniform thickness using only cuboid elements and consequently, the development of the proposed RFEM formulation is completed. After investigating various case studies, the competence of the proposed formulation is evaluated thoroughly. The results of RFEM came on a proper agreement with the FEM results in a way that the maximum difference between these results in dynamic analysis was about 3%.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-28T07:00:00Z
      DOI: 10.1142/S0219455422500997
       
  • Three-Dimensional Response of Multilayer FG-GPLRC Spherical Panels Under
           Blast Loading

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      Authors: Yasin Heydarpour, Parviz Malekzadeh, Hanxing Zhu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In the present research, the dynamic responses of the multilayer functionally graded graphene platelets reinforced composite (FG-GPLRC) spherical panels under blast loading are studied. Three-dimensional elasticity theory is employed to derive the governing equations. The distribution of graphene platelets (GPLs) in each layer is uniform and random with a constant weight fraction. GPLs concentration across the panel thickness may be uniform or graded. The layerwise-differential quadrature method (LW-DQM) together with a non-uniform rational B-spline-based multi-step time integration scheme is used to discretize the motion equations. The convergence behavior of the method is examined numerically. Further, to assure its accuracy, the results in the limit cases are compared with those available in the literature. Finally, through the parametric studies, the effects of material and geometrical parameters such as GPLs distribution patterns, GPLs weight fraction and dimension ratios on the transient responses of the FG-GPLRC spherical panels subjected to blast loading are investigated.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-25T07:00:00Z
      DOI: 10.1142/S0219455422501115
       
  • Effect of Permafrost on Seismic Performance of Railway Bridge Pile
           Foundation with Elevated Cap

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      Authors: Xiyin Zhang, Jiada Guan, Xingchong Chen, Wansheng Pei, Shengsheng Yu, Yi Wang, Wanping Wang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Pile foundation with elevated cap is always applied for railway bridges in permafrost region to minimize the thermal disturbance to vulnerable permafrost. Permafrost can influence the failure characteristics of the pile foundation under earthquakes and complicate the seismic performance evaluation of railway bridges with pile foundations in seismically active zones. Quasi-static tests of reduced scale models were carried out to investigate failure characteristics and hysteretic behaviors of the pile foundation with elevated cap in permafrost. Test results showed that the existence of permafrost can increase the stiffness of the foundation soil and then inhibit crack propagation of the unfrozen topsoil around the bridge pile foundation. Quite differently from the pile foundation in unfrozen soils, severer damages occurred at the pile foundation in soils with permafrost. Thus, the topsoil crack will be mitigated while the pile failure will be aggravated if strong earthquake occurs in permafrost regions for railway bridge pile foundation with elevated cap. Otherwise, the permafrost significantly influenced the loading bearing capacity and deformation features of the pile-soil interaction (PSI) system under seismic loads. The PSI system with permafrost has better energy dissipation than that with unfrozen soils due to the severe damage of the pile foundation. A simplified formula was developed to estimate the equivalent stiffness of the PSI system. It is indicated that the stiffness of the PSI system with permafrost degraded more severely than that with unfrozen soils. Therefore, permafrost effect cannot be neglected in seismic design of railway bridge pile foundations with elevated cap.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422410024
       
  • Wind Tunnel Study on Aerodynamic Characteristics of the Train on Viaducts
           with a New Type of Wind–Noise Barrier Under Cross Wind

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      Authors: Shuo Jiang, Yunfeng Zou, Xuhui He, Chenzhi Cai, Lihua Zhai, Xingzhong Nong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Traditional noise barriers are often designed only by considering its noise reduction effects, but designer ignores that it may transfer too much aerodynamic force to the bridge. In order to meet the wind resistance and noise reduction requirements of the elevated lines crossing an urban area at the same time, a new type of wind–noise barrier (NT-WNB) is proposed. The noise reduction effect is evaluated by a numerical method, and the influence of the wind–noise barriers’ rotation angle on the aerodynamic characteristics of a train–bridge system was studied by sectional model wind tunnel tests. The results show that the NT-WNB has effective noise reduction in the frequency range of 500–1600 Hz, and the noise reduction can be increased when install barriers with upward incline blade. Although an angle combination type of wind–noise barrier can optimize the lateral force and the lift of the train at the same time, which may cause high turbulence in the corresponding area. The NT-WNB can reduce the wind load of the bridge–barrier system by 22%, which is more conducive to the safety of the bridge and the barrier.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422410048
       
  • Aerodynamic Characteristics of Express Freight Train on Bridges Based on
           Wind Tunnel Tests

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      Authors: Jingcheng Wen, Qi Li, Lin Zhao, Qi Huang, Zhenggang Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The express freight trains are being developed rapidly in China, and they have the characteristics of smaller axle weight and higher velocity compared with the normal freight trains. The running safety of the trains on the bridge is significantly affected by the strong crosswind, which may cause overturning accidents in severe cases. The wind tunnel tests of the express freight train–bridge scale models are conducted in this study to investigate the aerodynamic characteristics of the vehicles when they run on the box girder bridge and the double-deck steel truss bridge. The uniform flow and the atmospheric boundary layer (ABL) flow are constructed respectively to compare the differences of the aerodynamic characteristics under different flow fields. The test results show that the distribution of pressure coefficients on the car body is related to the type of test flow field and bridge, and it is also greatly affected by the running position on the bridge as well as the location of the vehicle in the train. The magnitude of the side force coefficients and the rolling moment coefficients of the vehicle on the steel truss bridge are less than those on the box girder bridge. The influence of the flow field type on the side force coefficients of the middle vehicle is slightly larger than that of the tail vehicle, but it has a low correlation with the type of bridge. When the vehicle is on the windward track of the bridge, the values of power spectral density (PSD) of the side force are larger than those on the leeward track. The results provide data support for the running safety research of the express freight trains and reference for the railway vehicle wind tunnel test method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S021945542241005X
       
  • Running Safety Assessment of a Train Traversing a Long-Span Bridge Under
           Sudden Changes in Wind Loads Owing to Damaged Wind Barriers

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      Authors: Yan Han, Xun Zhang, Lidong Wang, Zhihui Zhu, C. S. Cai, Xuhui He
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In the event of partial damage to the wind barriers installed on a bridge, the wind loads of a train will change abruptly as they enter and exit the damaged area, resulting in the deterioration of the train running safety. This study aimed to assess the running safety of a CRH2 high-speed train traversing a four-tower cable-stayed bridge with damaged wind barriers. Formulas were deduced for the static and dynamic wind loads on the bridge and train and their combined effect. The aerodynamic coefficients of the train and bridge were obtained through wind tunnel tests of a train–bridge sectional model, and a model of the wind–train–track–bridge coupled system was established using multi-body dynamics and the finite element method. The effects of the length of the damaged area and average wind speed on the train running safety were investigated based on the proposed model. The results reveal that the car body lateral displacements and accelerations reach their maximum amplitudes when the vehicles enter and leave the damaged area, respectively. The amplitude of the car body lateral displacement increases as the length of the damaged area increases, until it reaches 72[math]m. The wheel load reduction rates (WLRRs) and derailment coefficients (DCs) of the vehicles increase owing to the damage of the wind barriers; however, the percentage increases for each vehicle are considerably different. The train can safely traverse the damaged area of wind barriers at a designed speed of 180[math]km/h when the average wind speed is lower than 10[math]m/s. When the average wind speed reaches 20[math]m/s, the train can still safely cross the damaged area if the length of the damaged area is less than 12[math]m.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422410103
       
  • Seismic Response on Soil–Structure Interaction of Asymmetric Plan
           Buildings with Active Tuned Mass Dampers

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      Authors: Kumar Vanshaj, Aravind Kumar Shukla, Mukesh Shukla
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Many studies on structural control have been done in recent decades to enhance the safety and serviceability of high-rise structures or towers against earthquakes and severe winds. Because most structures have an unbalanced layout, when they are exposed to an earthquake, they undergo torsion effects, which exacerbate the structural reaction. Also, such structures might be built on soft soil, where the influence of the Soil–Structure Interaction (SSI) would be significant. Thus, taking into account the SSI effect, a mathematical model is developed in this study to determine the seismic performance of an irregular multi-story structure with Active Tuned Mass Dampers (ATMDs) at the top floor. The results were produced utilizing MATLAB/SIMULINK software using the proposed hybrid Shallow Neural Network (SNN) technology and Shuffled Shepherd Optimization (SSO). The seismic response of 40-story asymmetric project buildings is studied using this model. The findings showed that using ATMDs on the higher floors of 40-story structures on soft soil reduced the produced structural reflexes. When compared to the Particle Swarm Optimization (PSO) and Ant Lion Optimization (ALO) algorithms, the suggested technique outperforms them both.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422501024
       
  • Effect of Strain Rate on the Compressive Behavior of Polyurethane Bonding

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      Authors: Yonggang Shen, Chengquan Wang, Yong Gan, Dongqiang Chen, Sumanth Kolli
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper discusses material named Polyurethane bonding which can be used in the stabilization of railroad ballast layer. An experimentation of the static and dynamic response of this material is important in designing appropriate solutions for railroad ballast layer, especially for the transition zone. A comprehensive study on the SHPB testing of Polyurethane bonding is presented in the strain rate range of 1000[math]s[math]–4000[math]s[math]. Variable power law was used to predict the material response at elevated strain rates as high as 10,000[math]s[math]. These results are compared with the material’s quasi-static response. The effects of strain rate on material parameters like Young’s Modulus and Yield Strength were investigated under various high strain rate dynamic experiments. It was found that the yield strength as well as Young’s modulus increased with the strain rate and the trend was more evident at higher strain rates. Quasi-Static Uniaxial Compression tests gave the typical stress–strain relationship of the material. A close investigation of the material response indicates that the behavior of this class of Polyurethane has a close resemblance with PMMA at the quasi-static as well as at various high strain rates.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422501103
       
  • Optimization Design of the Magnetic Multi-Mass Damper for Multi-Frequency
           Vibration Suppression

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      Authors: Xi Wang, Zhenyuan Xu, Dida Wang, Tao Wang, Guoqiang Fu, Caijiang Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      It is widely demonstrated that the tuned mass dampers (TMDs) are efficient to suppress resonant vibration, but the effective bandwidth is narrow and the robustness of the system is not enough, especially applied to variable frequency excitation. This paper presents an optimization design method of multi-mass damper (MMD) for variable multi-frequency vibration control. The dampers mounted on the primary system are made up of one main TMD and two MMDs, and each MMD is made up of three mass dampers, whose damping is provided by magnetic dampers, whose analytical model is established for optimization. The optimization objective function proposed is based on the variance, the difference between the maximum and the minimum values, root-mean-square values of the primary system vibration, which can help attenuate the vibration and improve the robustness of the primary system theoretically. The simulation results indicate that the vibration of the primary system under multi-frequency is suppressed 6[math]dB by the designed dampers. In the experiments, the optimized damping ratios of every mass damper are realized using the magnetic dampers. The vibration amplitude of the primary system can be suppressed more than 50% when the main TMD and MMDs start work, the dramatic fluctuation of frequency response is replaced by gentle transition, and the experimental results are consistent with the simulation results well.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-24T07:00:00Z
      DOI: 10.1142/S0219455422501127
       
  • A Practical Stress Correction Method for Improving Stability of
           State-Based Peridynamics Based On Stress Equilibrium Equation

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      Authors: Quan Gu, Zhe Lin, Lei Wang, Baoyin Sun, Jinghao Pan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      State-based peridynamics (SPD) is effective for simulating fracture and damage in different materials. However, the solutions may suffer from numerical instabilities, particularly for strong nonlinearity cases or large displacement cases, leading to inaccurate predictions or oscillation in responses. This paper proposed a novel practical method to solve the instability problem of SPD based on stress equilibrium equation, referred to herein as the stress correction method (SCM). A correction force is applied on each SPD point surrounding the loading points. The correction force is defined as the difference between an internal force obtained by the stress equilibrium equation and that obtained by the force states of the SPD. Four examples are presented herein to verify the accuracy and stability of the proposed method in various conditions, e.g. static and dynamic analyses of elastic and plastic models subjected to force and displacement boundary conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-23T07:00:00Z
      DOI: 10.1142/S0219455422500948
       
  • Effects of Curved Wind Barrier on the Aerodynamic Characteristics of a
           Train–Bridge System and Its Static Wind Load

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      Authors: Wei Tao, Ping Lou, Yunfeng Zou, Chenzhi Cai, Xuhui He, Shuo Jiang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Wind barriers are important measures that guarantee the running safety of high-speed trains under crosswind conditions, however, they can change the aerodynamic coefficients of a train–bridge system and the distribution of the flow field around a train and bridge, and studies have often ignored the static wind load characteristics of wind barriers. In this paper, the effects of height and porosity on the curved and vertical fence-type wind barriers on the aerodynamic characteristics of a train–bridge system are investigated by using numerical simulation and wind tunnel test methods. The static wind loads of the two types of wind barriers are analyzed by comparing the drag coefficients and the surface wind pressure distributions. The results show that, compared with the vertical wind barrier, the curved wind barrier can reduce the drag force and moment of a train while reducing the impact of the aerodynamic forces on a bridge. The static wind load of the curved wind barrier is less than that of the vertical wind barrier, when a train is on the windward side of a bridge, the drag coefficient of the curved wind barrier is only about 35% of that of the vertical wind barrier.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-19T07:00:00Z
      DOI: 10.1142/S0219455422410061
       
  • The Effect of Intermediate Ring Support on the Vibration Behavior of
           Functionally Graded Conical Shells

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      Authors: M. Zarei, G. H. Rahimi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, the free vibrational behavior of a thin-walled functionally graded conical shell with intermediate ring support is investigated. Theoretical formulations were established based on the first-order shear deformation theory. The governing equations of motion were solved using the Galerkin method. Applying a set of displacement functions, the equations of motion result in an eigenvalue problem, by solving which, the natural frequencies of vibration are determined. Material properties are assumed to be varied in the thickness direction according to the power-law volume fraction function. It has been attempted to examine the effects of ring support position on the natural frequencies of vibration and to introduce the optimal scenarios of the support placement to achieve a higher frequency. In addition, a 3D FE model was built in the ABAQUS CAE software in order to validate the results of the analytical model. The analytical results were in close agreement with the literature and also the numerical ones. Moreover, the effects of some commonly used end conditions, variations in the shell geometrical parameters, changes in the ring support placement have been investigated on the vibrational behavior.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-19T07:00:00Z
      DOI: 10.1142/S0219455422500857
       
  • Damage Detection of Bridge Structures Under Vehicle Loads Using
           Moving-Window Correlation Coefficient of Signals with Limited Sensors

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      Authors: Yifeng Zhang, Jinsong Zhu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Based on the moving-window correlation coefficient of signals, a damage detection method is proposed for bridge structures. The signals collected by two sensors during the vehicle crossing the bridge are intercepted as windowed pair time series, and the damage index is defined based on the correlation of them. The damage vector is composed of damage indices from the beginning to end according to the moving direction of the window, and the damage location can be determined by the peak information of all the damage vectors which are obtained by different sensor pairs. First, the damage detection method and corresponding detection steps are introduced. Then, the proposed method is validated by numerical simulation, and the influence of moving window length, moving step, the number of sensors, deviation of vehicle parameters and road-surface roughness on damage localization are discussed, respectively. Finally, the proposed method is validated by experiments using a two-axis vehicle and a steel–concrete composite beam. The results show that the proposed method can effectively identify the damage location. High-pass filtering of the raw data to remove trend items and wavelet noise reduction can significantly improve the accuracy of damage detection, and can accurately locate the damage in the presence of road-surface roughness. The damage detection result is not sensitive to vehicle parameter deviation, and the damage location can still be accurately identified when the vehicle weight or speed deviates 50% from the vehicle parameters in the reference data. In addition, the proposed method can make full use of the damage information between sensors, and can accurately identify the damage location with limited sensors. The number of sensors can be flexibly determined considering both accuracy and economy.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-19T07:00:00Z
      DOI: 10.1142/S021945542250105X
       
  • Dynamic Response of Rapidly Heated Rectangular Plates Made of Porous
           Functionally Graded Material

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      Authors: R. Ansari, S. Nesarhosseini, M. Faraji Oskouie, H. Rouhi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, the nonlinear thermally induced vibration in rectangular plates made of porous functionally graded materials (FGMs) due to thermal shock is studied based on a new numerical approach. The shear deformation influences are taken into consideration via Mindlin’s plate theory. The properties of the materials are also assumed to be temperature- and position-dependent. Moreover, the influence of elastic foundation is captured by the Winkler–Pasternak model. For deriving the governing equations, Hamilton’s principle, transient 1D Fourier-type heat conduction equation and von Kármán hypothesis are utilized. The relations of paper are written in a new matricized format for computational aims. The generalized differential quadarature (GDQ) method and Newmark’s direct integration scheme are used for solving the heat equation. Furthermore, solving motion equations is done based on the variational differential quadrature (VDQ) formulation. The effects of important parameters including material porosity and elastic foundation on the thermal shock response of porous FG plates are investigated in the numerical results.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-18T07:00:00Z
      DOI: 10.1142/S0219455422500900
       
  • Applicability of Damped Outrigger Systems Using Timoshenko Beam Theory

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      Authors: Chuangjie Fang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Recently, applying damped outriggers in high-rise buildings to reduce vibration due to earthquake and wind has attracted a lot of attention. By placing energy dissipated devices vertically between the end of outriggers and perimeter columns, the damped outrigger systems emphasize the supplementary damping rather than stiffness. This paper investigates the applicability of viscously damped outrigger systems using Timoshenko beam theory. First, the building is modeled as a cantilevered Timoshenko beam, and the damped outriggers are simplified as equivalent complex rotational spring. With the assembly of dynamic stiffness of the damped outrigger system, the Wittrick–Williams algorithm and Newtonian iteration are then combined to calculate the dynamic characteristic of the system. The proposed approach has been verified by finite element method through a case study. The shear deformation and rotatory inertia of the core, later blended as slenderness ratio of the height-radius following Timoshenko beam theory, stiffness ratios of core-column and core-outrigger, and the number of damped outriggers are subsequently evaluated associated with supplementary damping as applicability analysis. This study shows the following: (1) adding damping amplifies twice to triple as the slenderness ratio increases from 5 to 25 for the first mode; (2) configurating more damped outriggers could provide stable damping contribution across modes with diminishing benefit; (3) Timoshenko beam analysis is better suited while Euler–Bernoulli beam analysis is an acceptable approximation only when the slenderness ratio of one-damped outrigger system is bigger than 25 and the first mode is predominant; and finally (4) the stiffness ratios of core-column, core-outrigger and stiffness of dampers have substantial influence on structural damping, particularly within the range smaller than 1, 10 and 4, respectively, but the presence of properly designed negative stiffness of dampers could bring substantial improvement. This study could serve as guidelines to apply damped outrigger systems in high-rise buildings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422500766
       
  • A Unified Solution for Free Vibration Analysis of Beam-Plate-Shell
           Combined Structures with General Boundary Conditions

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      Authors: Shuai Zhang, Xiang Zhu, Tianyun Li, Caiyu Yin, Qingsheng Li, Rugang Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A semi-analytical method is presented to analyze free vibration response of beam-plate-shell combined structures with general boundary conditions. Based on the beam-plate-shell energy theory, the coupled annular plate-conical-cylindrical-spherical shell with stiffened rings and bulkheads regarded as the theoretical model is constructed. The unified displacement admissible functions of each substructure are expanded as modified Fourier series and auxiliary convergence functions along generatrix direction and Fourier series along circumferential direction. Virtual spring technology is adopted to express the energy stored at the junction of adjacent substructures and both boundaries. The energy variational procedure and Ritz method are used to obtain the vibrational governing equation of the combined structure. The present method provides an analytical way for the vibrational response of complicated combined structures. The convergence, accuracy and reliability are validated by comparing the free vibrational response with those of the references and finite element method. Some numerical examples show effects of different boundary conditions on the free vibration. And the influence of stiffened rings and bulkheads treated as Euler-beams and annular plates is also discussed from quantity, size and spatial distribution, offering a feasible way to design the reinforced structures and optimize the bulkheads in engineering problems.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422500808
       
  • Dynamic Instability of Sandwich Beams Made of Isotropic Core and
           Functionally Graded Graphene Platelets-Reinforced Composite Face Sheets

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      Authors: Gholam Reza Asgari, Amirbahador Arabali, Masoud Babaei, Kamran Asemi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, dynamic instability of a sandwich beam made of an isotropic core and functionally graded (FG) graphene platelets-reinforced composite (GPLRC) face sheets is investigated for the first time. A Frostig theory for soft core and third-order shear deformation theory (TSDT) for sheets are used. Hamilton’s principle is used to derive the governing equations of motion, and by applying Bolotin’s approach, the dynamic instability regions (DIRs) are investigated. A comprehensive investigation is conducted to assess the effects of different weight fractions of nanofiller, various GPL patterns, boundary conditions, slenderness ratio, the thickness of face sheet and static load factors on the DIRs of the beam.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422500924
       
  • Size-Effect Analysis on Vibrational Response of Functionally Graded
           Annular Nano-Plate Based on Nonlocal Stress-Driven Method

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      Authors: Mohammad Shishesaz, Mojtaba Shariati, Mohammad Hosseini
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Dynamic analysis of functionally graded size-dependent annular nano-plate is the main concern in this study. To obtain the vibrational behavior of this plate, the stress-driven nonlocal integral elasticity, as well the strain gradient theory were used in conjunction with the classical plate theory. The resulting equilibrium equations were solved using the generalized differential quadrature rule (GDQR) and the influences of various parameters such as; size-effect parameter, material heterogeneity index, the aspect ratio of the inner to outer radii, and the effects of different boundary conditions were investigated on the vibrational behavior of the nano-plate, based on different types of boundary conditions. Results indicate that the natural frequencies increase with an increase in the heterogeneity index [math] and the increase in size-effect parameter shows a similar effect in both models. Additionally, for the simply supported and free-edge boundary conditions (for both edges), as well as the free and knife-edges, and simply supported-free edges, the strain gradient theory predicts higher values of frequency ratios as [math] was increased. Similar results were obtained for the remaining types of boundary conditions, with a higher sensitivity to [math], provided the stress-driven model is used. This behavior can be interpreted as the sensitivity of the nano-plate to [math] that is manifested by the use of the stress-driven model for the prediction of vibrational behavior of the nano-plate.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422500985
       
  • Modal Identification Technologies for High-Rise Buildings Under
           Non-Stationary Excitations

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      Authors: Meng-Meng Sun, Qiu-Sheng Li, Kang Zhou, Xu-Liang Han
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      For high-rise buildings subjected to typhoon or earthquake actions, the excitations are likely non-stationary, which inevitably violates the stationary assumption that is generally adopted by conventional modal identification methods. Under such a condition, conventional modal identification methods may not be applicable, and their performances need to be evaluated. To this end, the performances of seven widely used modal identification algorithms for structural modal estimation under non-stationary excitations are evaluated via a numerical simulation study. Then, three methods with good performance are selected to evaluate their applicability and accuracy for field measurements involving non-stationary excitations. From the comparative study, a time–frequency domain method with the best performance among these seven methods is employed to investigate the structural dynamic properties of a 509-m-tall skyscraper under typhoon and earthquake excitations. Based on the reliable modal estimates, the relationships between the modal properties with response amplitude and environmental temperature are presented and discussed. This paper aims to identify the effective methods for accurate estimation of structural modal parameters based on non-stationary structural responses and investigate the structural dynamic properties of high-rise buildings under typhoon and earthquake excitations.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422501048
       
  • Softening-Spring Phenomenon in Large Amplitude Vibration of Two-Layer
           Bi-Material Beams

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      Authors: Na Hao, Liao-Liang Ke
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The purpose of this study is to analyze the nonlinear vibration behavior of two-layer bi-material beams by using the Euler beam theory and Timoshenko beam theory. It is assumed that material properties satisfy a power law distribution along the thickness direction. The differential quadrature (DQ) method in conjunction with an iterative algorithm is employed to solve the nonlinear governing equations for two-layer bi-material beams. Numerical results are presented to show the influence of Young’s modulus ratio and thickness ratio on nonlinear frequency ratio–amplitude curves of two-layer bi-material beams. It is observed that the nonlinear frequency ratio–amplitude curves are unsymmetrical with the hinged end because of bending-extension coupling effect in two-layer beams. It is also observed that the hinged–hinged two-layer beams may occur the softening-spring nonlinearity when the amplitude of oscillation is small. This softening-spring nonlinearity is dependent on the thickness ratio, Young’s modulus ratio, vibration amplitude, layer number and boundary condition. The greater the difference of material properties between the two layers is, the more obvious the softening-spring nonlinearity becomes.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422501061
       
  • Damping and Frequency Response Characteristics of Functionally Graded
           Fiber-Reinforced Composite Cylindrical Shells

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      Authors: Qiyi Dai, Yunfei Liu, Zhaoye Qin, Fulei Chu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents research on the modal damping and frequency response of functionally graded fiber-reinforced composite cylindrical shells considering the internal damping. Based on the Love shell theory and energy approach, the dynamical equations of cylindrical shells are established. In the process of variable separation, the Haar wavelet series and trigonometric functions are respectively to represent the axial and circumferential modes. Based on the microscopic damping prediction method and multi-cell model of hybrid materials, the equivalent damping and elastic characteristics of composite materials are determined. Then the damping and frequency response characteristics are solved by the complex modulus method. The present analysis is validated by comparing the results with those in the literature and finite element simulation. The effects of fiber content and distribution, lamination and geometry configuration on damping and frequency response properties are further analyzed. The analysis show that the damping decreases monotonically with the increase of fiber volume fraction. The damping behaviors may be improved by changing the fiber distribution type and stacking sequence. Increasing the internal damping of composites can obviously reduce the vibration amplitude in the resonance region, especially in the high frequency range.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422501073
       
  • Basin Effects on the Seismic Fragility of Steel Moment Resisting Frames
           Structures: Impedance Ratio, Depth, and Width of Basin

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      Authors: Rajesh Parla, Bharath Shanmugasundaram, Surendra Nadh Somala
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Deep sedimentary basins often increase the intensity of ground motions, but this effect is not considered explicitly in most codal provisions. The effect of basin amplification on structures to the fragility level is significant to study. For the first time, the effect of basin amplification on Steel Moment Resisting Frames (SMRF) is presented as a function of the basin material and geometry. This paper evaluates the effect of basin material, basin depth, and basin width on Peak Ground Velocity (PGV), Spectral Acceleration (Sa), and fragility of 4, 8, 12, and 20 story steel structures using synthetic ground motions simulated in SPECFEM3D. It has been found that the variation in basin width and impedance ratio can increase the spectral acceleration by a factor of 4 and 2.5, respectively. The response of SMRF is computed by incremental dynamic analysis, and fragility curves are derived for the collapse limit state. Results of fragility analysis reveal that SMRF structure is more fragile to variation in impedance contrast between basin-bedrock. It has been observed from the results that the collapse intensity measure for impedance ratio variation is 40% and 19% lesser on average than the width and depth variation, respectively. Comparison between the present fragility analysis results and HAZUS fragility parameters indicates that the vulnerability of structure located in the basin is underestimated in its current provisions, and the SMRF would need to increase its strength two times to account for basin amplification.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422501085
       
  • Machine Learning to Identify Dynamic Properties of Railway Track
           Components

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      Authors: Sakdirat Kaewunruen, Jessada Sresakoolchai, Henry Stittle
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Investigating the condition of rail track components is important for track maintenance and developing a greater understanding of track design. Railway inspection can be destructive and non-destructive approaches. In the railway industry, the non-destructive approaches are preferred because they retain the track in operation thus significantly reducing the cost of fault testing. One of the non-destructive approaches is using machine learning which is applied in this study. Field measurements and advanced analysis of results are used to extract track properties. This study creates, tunes and examines the validity of different machine learning techniques. The aim is to extract the dynamic track properties from the in-field measurements without needing the intermediary steps, saving both time and effort. Contributions of this study demonstrate that machine learning techniques have the potential to save cost and time for railway inspection. Moreover, the accuracy is satisfied. The following models are produced: Linear Regression, [math]-Nearest Neighbors, Gradient Boosting and a Convolutional Neural Network. We observe the limitations of linear regression and tune the remainder, producing three models with low errors.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-16T07:00:00Z
      DOI: 10.1142/S0219455422501097
       
  • A Multi-Excitation Method of Damage Detection in Plate-Like Structure
           Based on Wavelet Packet Energy

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      Authors: Yang Yu, Wentao Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Damage detection technology based on wavelet packet energy has been widely applied to structural health monitoring, especially for one-dimensional structures. With more complex vibration characteristics than one-dimensional structure, two-dimensional structure is common in ship structure. It is a challenge for using wavelet packet energy methods to detect damage in two-dimensional structures. In this study, based on the wavelet packet energy eigenvector, a novel concept of detection index ratio (DIR) is defined to characterize the damage location ability of the excitation force. Based on the above research, a multi-excitation method of damage location in plate-like structures is proposed. In this method, a series of half-sine pulse excitation forces with different frequencies are applied to the structure, and wavelet packet transform (WPT) is used to decompose the vibration response of the intact structure and the damaged structure. The energy ratio changes in frequency bands on all measuring points are taken as the preliminary damage detection index, and the final detection index is obtained by synthesizing the preliminary indexes under various excitation. Moreover, to verify the effect of the proposed method, several tested damage cases are presented. The results show that the proposed method can locate single and multiple damage more accurately and has better noise robustness than the traditional detection method under single excitation.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-10T08:00:00Z
      DOI: 10.1142/S0219455422500912
       
  • Thermal–Structural Coupling Analysis for Multiple Honeycomb Plates
           Connected by Hinges

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      Authors: Yuteng Cao, Dengqing Cao, Guiqin He, Yuxin Hao, Xinsheng Ge, Lun Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The dynamical model of multiple honeycomb plates connected by hinges, including the thermal–structural coupling effect, is investigated in this paper. Under the assumption of small deformations and strains, the classical plate theory is used to establish the dynamical model of the honeycomb plate. The Chebyshev polynomial is adopted to describe the deformation of the plate and the linear torsional spring to represent the elastic hinge. Using the Rayleigh–Ritz method, the characteristic equation of the honeycomb sandwich structure is derived, from which the natural frequencies are obtained. Considering the thermal effect of the plate, the thermal–structural coupling dynamical equation is obtained. The thermal conduction in the thickness direction is calculated by the finite difference method. The present model is validated by comparing with the result generated by an equivalent orthotropic plate model established by the finite element (FE) software MSC Patran. The response analysis reveals the important effect of the metal skin and the hinge stiffness on the dynamic characteristics of the honeycomb sandwich structure. Numerical simulations reveal thermal–structural coupling features for the multi-honeycomb-plate structure from the perspective of the change in dynamic characteristics and the distribution of the temperature gradient. The thermal–structural coupling calculation method adopted herein can be used to solve the thermal conduction of the plate. It serves as the theoretical method for analyzing the dynamical behavior of the solar panel subjected to the solar heat.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-10T08:00:00Z
      DOI: 10.1142/S0219455422500936
       
  • Dynamic Modeling and Stability Analysis of a Heavy-Duty Flywheel
           Rotor-Bearing System with Two Cracks

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      Authors: Chuandi Zhou, Yibing Liu, Wei Teng, Haosui Zhang, Haiting He, Chao Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Cracks have a significant impact on the stability of rotating machinery. However, most studies focus on rotating machinery with only one crack. This paper discusses the influence of two cracks on the stability of a flywheel rotor-bearing system. In this study, the dynamic models of vertically placed flywheel rotor-bearing system with two open cracks and two breath cracks are established using the finite element method (FEM). Floquet theory is used to calculate the stability of the system and the influence of depth and positions of cracks are analyzed. The results show that breathing cracks cause more unstable regions than open cracks, and the range of rotating speeds over which the rotor is unstable increases with increasing crack depth. In addition, it is observed that when the crack locations are adjacent, the unstable region will become very large, covering most of the crack depth range and speed range, making the rotor extremely unstable. Besides, the bearing stiffness causes an offset in the unstable regions, whereas the damping influences the instability value of the rotor.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-10T08:00:00Z
      DOI: 10.1142/S0219455422501036
       
  • Dynamic Buckling of Composite Structures Subjected to Impulse Loads Using
           the Lyapunov Exponent

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      Authors: U Song-Hak, Yong-Il So, Wang-Myong So
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper focuses on dynamic buckling of composite structures subjected to impulse loads. Using the Lyapunov exponent, the Budiansky–Hutchinson criterion is improved and its algorithm is constructed. Based on it, the nonlinear dynamic buckling loads are evaluated for typical composite structures such as a fiber-reinforced composite plate, composite laminated cylindrical shells and a laminated plate with delaminations and matrix cracks that are all subjected to impulse loads. The improved criterion of dynamic buckling is validated through comparisons with the results in the published literatures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-05T08:00:00Z
      DOI: 10.1142/S0219455422500869
       
  • Passive Suppression of Resonance Vibrations of a Plate and Parallel Plates
           Assembly, Interacting with a Fluid

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      Authors: Maksim A. Iurlov, Alexander O. Kamenskikh, Sergey V. Lekomtsev, Valerii P. Matveenko
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      We present the results of a series of experiments, which study the effect of the fluid layer height, viscosity and free surface waves on the vibration damping of a thin rectangular plates interacting with a fluid. The suppression technique is based on the shunt circuit connected to the piezoelectric elements. The possibility of using the previously proposed mathematical formulation and approach for calculating the optimal values of the parameters of a [math]-circuit in systems with hydrodynamic dissipation is estimated. The experimental results presented confirm its reliability. It has been demonstrated that the efficiency of vibration damping of a single plate structure changes insignificantly with increasing height of the fluid layer except for some interval. At a small amount of the liquid, the waves on its free surface disturb the piezoelectric element reducing its efficiency. Using as an example an assembly of two parallel plates damping of “in-phase” and “out-of-phase” modes has been shown using one location of piezoelement.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-05T08:00:00Z
      DOI: 10.1142/S0219455422501012
       
  • Thermal Buckling Analysis of Cracked Functionally Graded Plates

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      Authors: Thom Van Do, Duc Hong Doan, Nguyen Chi Tho, Nguyen Dinh Duc
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Because structures made of FG material often operate in high temperature environments, it is critical to understand the mechanical behavior of these structures while taking temperature into consideration. As a result, the phase-field model is employed in this work to investigate the thermal buckling of fractured functionally graded material (FGM) plates. Additionally, this study demonstrates the difference between the plate’s static stability response to thermal load in the case of temperature-dependent (TD) material mechanical properties and in the case of temperature-independent (TID) material mechanical properties, illustrating that the calculation for these two cases will appear to be highly skewed. This provides a scientifically valid foundation for scientists to adopt a more realistic computation model. The equations are based on the third-order shear deformation plate theory (TSDT) of Reddy. This work proves that this discrepancy strongly depends on the material, boundary condition, crack length as well as thickness of the crack plate, it has never been explored in published work, the results give very useful and needful information for scientists to choose the best accuracy case to calculate and apply in practice.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-03T08:00:00Z
      DOI: 10.1142/S0219455422500894
       
  • Normal and Oblique Impact on Polyurea-Coated ASTM1045 Steel Plates by
           Small-Arms Projectiles

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      Authors: Long Zhang, Xin Wang, Chong Ji, Gang Wu, Haojie Zhu, Zeyan Han
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Small-caliber steel core projectiles fired by light weapons pose a great threat to metal structures. Coating with polyurea (PU) is a potential option to improve the anti-penetration performance of metal structures. In this work, we carried out numerical simulations to clarify the dynamic characteristics of PU-coated ASTM1045 steel plates subjected to oblique penetration by 5.8-mm small-caliber steel core projectiles. The failure modes, dynamic response process, energy absorption characteristics, and comprehensive protection effects of target plates with different coating positions and thicknesses during the penetration process were compared and analyzed. The result showed that coating with a certain thickness of PU could enhance the protection ability of the steel plate against the oblique penetration of projectiles. In contrast to the results obtained from experiments in which the projectile penetrated the composite plate normally, when the PU coated both sides, the effect of improving the oblique penetration resistance of the steel plate was the best. The effect was lowest with a PU layer only on the back face. This study provides a reference for strengthening the bulletproof performance of various systems, including steel structures, weapons, and vehicles.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-03T08:00:00Z
      DOI: 10.1142/S0219455422500961
       
  • Similarity Research on the Action of a Centrifuge Scaled Near-Field
           Underwater Explosion on a Concrete Gravity Dam

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      Authors: Shang Ma, Zhenqing Wang, Shutao Li, Yeqing Chen, Qin Zhu, Benzhi Min
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Concrete gravity dams are a common form of dams. The dynamic response analysis of concrete gravity dams under the action of underwater explosions is indispensable for survivability assessments. Due to the constraints of the environment and other conditions, an underwater explosion test of a prototype concrete gravity dam is difficult to achieve. The centrifuge scaled-down test that satisfies similarity theory provides a new way to study the dynamic response of underwater explosions on concrete gravity dams. In a near-field explosion, the shock wave of an underwater explosion will cause direct damage to the gravity dam, and the detonation products after the shock wave will aggravate the damage. Under the premise of verifying the concrete dynamic response material parameters and the fluid–solid coupling model of the underwater explosion, numerical calculations of the scaled underwater explosion model of the centrifuge and the prototype underwater explosion were carried out, and the similarity between the scaled dam response model of the underwater explosion centrifuge and the prototype was discussed. The analysis shows that the scaled-down centrifuge model can better reflect the local damage of the prototype dam subjected to shock waves. The difference between the scaled centrifuge model and the prototype model of underwater explosion damage to the dam is concentrated on the overall damage. The damage effect of detonation products on the prototype dam body is mainly concentrated in the middle and lower parts of the dam body, while the damage effect of detonation products on the dam body in the scaled-down model is mainly concentrated in the middle and upper parts of the dam body.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-03-02T08:00:00Z
      DOI: 10.1142/S0219455422500845
       
  • A Unified Solution Method for Free Vibration of Arbitrarily Shaped Plates
           without or with Cracks

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      Authors: Yuyu Song, Kai Xue, Qiuhong Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a new approach for analyzing the free vibration of thin plates with arbitrary piecewise smooth curvilinear contour under various boundary conditions. It can also be applied to plates with cracks. This approach is based on the transformation of energy integral expressions and the domain decomposition technique. Furthermore, boundary conditions are modeled by using linear springs to restrain the plate edges. For obtaining the expressions of energy integral, the arbitrarily shaped domain of integration is divided into several trapezoid domains with curved sides by a set of parallel lines passing through the intersection points of contour curve segments. Then, Jacobi orthogonal polynomials are introduced as the admissible functions, so that the repeated integrals in the energy expressions are reduced to definite integrals analytically. At this point, the calculation method of the energy functional is determined by the equation forms of the curve segments of the plate contour. When the equations of the curve segments allow the integrands to have analytic primitive functions, the energy functional has an analytical solution. Otherwise, the Gauss–Legendre method is used to obtain the numerical solution. Accordingly, the arbitrarily shaped plate with cracks is decomposed into several arbitrarily shaped subdomains based on the cracks. Each subdomain is handled according to the above procedure. The continuity conditions at the interconnecting interfaces of the subdomains are realized by linear springs. The plate without or with crack is modeled by setting the spring stiffness to infinity or 0. The accuracy of the proposed method is verified by comparing the obtained results with the published results. Furthermore, the vibration characteristics of plates with various shapes, such as astroid-shaped plates and cracked elliptical plates, are investigated. These new results can serve as benchmarks for further studies on the vibration of plates.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-28T08:00:00Z
      DOI: 10.1142/S0219455422500973
       
  • Estimation of Road Roughness Based on Tire Pressure Monitoring

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      Authors: Qing Zeng, Xiaoyang Hu, Xiaodong Shi, Yiting Ren, Yuan Li, Zhongdong Duan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The evaluation of road roughness plays a critical role in the life-long maintenance of the highway system. This study proposes a Kalman Filter-based scheme to evaluate the road roughness indirectly from the response of a moving adapted monitoring vehicle. Key feature of the scheme is the use of measurements from dynamic tire pressure of unsprung mass components that directly interact with roads. Combination of ideal gas law and elastic contact model results in a nonlinear relationship between the tire pressure and the contact force, in which the parameters are calibrated by the Extended Kalman Filter. Identification of vehicle’s physical parameters adopts the power spectrum method with a known-size bump test. Subsequently, the road roughness is treated as unknowns in the vehicle’s state-space equation and solved by the Discrete Kalman Filter with unknown inputs. The estimated road roughness profiles are then used to calculate the International Roughness Index and compared with that provided by the standardized laser profilometer, an outer-systematic comparison. On the other hand, available measurements are split into groups that measurements of tire pressure are used to predict the accelerations of the car body and wheels and compared with these accelerations directly measured from accelerometers, an inner-systemic comparison. Field tests are carried out on a 900[math]m long standardized road under two scenarios of with and without the bump and four different vehicle running speeds from 20 to 50[math]km/h. Consistence of comparison from different perspectives proves the reliability of the proposed scheme. In addition, the results unveil that the scenario with a lower running speed can offer a better estimation of road roughness.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-25T08:00:00Z
      DOI: 10.1142/S0219455422500730
       
  • Vibration Suppression Performance of FRP Spherical-Cylindrical Shells with
           Porous Graphene Platelet Coating in a Thermal Environment

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      Authors: Xudong Zu, Zhijiang Gao, Jing Zhao, Qingshan Wang, Hui Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, the vibration suppression effect of a fiber reinforced polymer (FRP) spherical–cylindrical shell coated with the porous graphene platelet (PGP) in a thermal environment is investigated. The dynamic equilibrium equation is derived by combining the first-order shear deformation theory and the Rayleigh–Ritz approach, together with the virtual spring technology and the multi-segment partition technique. After the free and forced vibration responses of this FRP combined shell with PGP coating are solved. The model is validated by the convergence analysis and comparison of the present results and literature or finite element results for different shell structures with and without coating under various boundary conditions. Using the present model, the parametric study is conducted to explore the effects of porosity distribution type, dispersion pattern of volume fraction porosity, nanofiller weight fraction, and thickness ratio of PGP coating on the transient response. This study provides a useful model and some suggestions for better improving the vibration suppression capability of coated shell structures in a thermal environment.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-25T08:00:00Z
      DOI: 10.1142/S021945542250081X
       
  • Influence of Temperature and Moisture on Free Vibration Behavior of Skew
           Laminated Composite Sandwich Panels with CNTRC Core

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      Authors: Vinayak Kallannavar, Subhaschandra Kattimani, H. Ramesh
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents the influence of temperature and moisture on the free vibration characteristics of skew laminated composite sandwich (SLCS) panels. The face sheets of the panels are made of graphite–epoxy composite, while the core consists of carbon nanotube-reinforced composite. The coupled hygro-elastic and thermo-elastic relations for the SLCS shells/panels are formulated using first-order shear deformation theory. The nonmechanical stiffness matrices are represented by the initial stress stiffness matrix developed using nonlinear strain–displacement relations. The temperature and moisture-dependent material properties are considered to analyze the laminated composite sandwich spherical, hyperbolic, ellipsoid, cylindrical Shells, and flat plates. Several numerical examples are comprehensively studied to establish the influence of temperature, moisture, the volume fraction of carbon nanotubes in the core material, functional gradation types, skew angle, and edge constraints on the vibration responses of SLCS shells. Further exploration is devoted to studying the combined effect of moisture, temperature, and the geometrical parameters such as length to width ratio, length to thickness ratio, radius-to-length ratio, and the core thickness to face sheet thickness ratios on the natural frequency of the skew laminated composite sandwich panels.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-25T08:00:00Z
      DOI: 10.1142/S0219455422500833
       
  • Effect of Cutout on the Stability and Failure of Laminated Composite
           Cylindrical Panels Subjected to In-Plane Pulse Loads

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      Authors: Vasanth Keshav, Shuvendu Narayan Patel, Rajesh Kumar, Gaurav Watts
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this investigation, the nonlinear dynamic buckling analysis and the failure analysis of laminated composite cylindrical (LCC) panel with different shapes of cutouts under the action of rectangular in-plane pulse loads are performed in the finite element framework. Cross-ply laminates which are balanced symmetric are considered in the investigation. The first ply failure load (FPFL) of the panel is evaluated and checked whether it occurs before the nonlinear dynamic buckling phenomenon considering Tsai–Wu failure criterion. Convergence and validation studies are undertaken, and the results are compared with those from the existing literature. The effects of loading duration, cutout area and cutout geometry on the panel are investigated in detail and results are reported. The results indicate that for the panel with cutout, its dynamic buckling load (DBL), in certain cases, compared to the static buckling load (SBL), can be lower even if the loading duration is half of its first natural period. Additionally, the vibration and the static buckling analyses of the panels are carried out as and when required.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-25T08:00:00Z
      DOI: 10.1142/S0219455422500870
       
  • Theoretical Prediction and Experimental Validity of Thermal Frequency
           Responses of Laminated Advanced Fiber-Reinforced Epoxy Hybrid Composite
           Panel

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      Authors: Pruthwiraj Sahu, Nitin Sharma, Hukum Chand Dewangan, Subrata Kumar Panda
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Thermal frequency responses of the hybrid laminated composite panel are theoretically computed using the finite element model and for the first time compared with in-house experimental data. The structural model for hybrid panel is derived using higher-order displacement polynomial functions (to maintain the necessary stress/strain continuity) and discretized through the isoparametric finite elements. Moreover, the elastic properties of the composite are evaluated suitably including thermal and physical parameters of the advanced fibers (Glass/Carbon/Kevlar) with the help of experimentations and numerical tool (via ABAQUS using mean-field homogenization). The variation of modal responses due to the change in temperature increment is computed through a generic computer code generated via the higher-order mathematical model. The numerical frequency values are compared with the earlier published numerical results and the experimentally recorded eigen frequencies. The experimental verifications related to the end boundaries indicate that the incorporation of the clamped boundary for one edge doubles the frequency, whereas the fraction of Kevlar fiber does not influence the stiffness (due to longitudinal modulus) parameter irrespective of the temperature change. Further, the conclusive understandings of the hybrid composite structural panel due to the inclusion of different advanced fibers and other design parameters (geometry, boundary and temperature) are deliberated in detail.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-25T08:00:00Z
      DOI: 10.1142/S0219455422500882
       
  • Large Amplitude Axisymmetric Free Vibration of a Closed Two-Dimensional
           Spherical Pressure Vessel with a Constrained Volume

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      Authors: Weeraphan Jiammeepreecha, Komkorn Chaidachatorn, Somchai Chucheepsakul
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The nonlinear axisymmetric vibrational modes of a closed two-dimensional spherical pressure vessel with a constrained volume are presented using the fundamental forms of surfaces. The strain energy of the spherical pressure vessel is derived as a quadratic function of the initial Eulerian, added, and total Lagrangian strains. Two-dimensional bilinear elements described in spherical polar coordinates with the symmetric boundary condition along both sides of the meridian line are used for investigating the nonlinear axisymmetric mode shapes of a spherical pressure vessel. Numerical results were obtained by a nonlinear finite element approach and verified in the case of an empty spherical shell for both lower and upper branches. This study showed that the spherical pressure vessel gave a higher nonlinear axisymmetric natural frequency than the empty spherical shell. The elastic modulus has a large effect on the nonlinear axisymmetric frequencies of both the lower and upper branches for the spherical pressure vessel. Changing the thickness and initial internal pressure significantly affects only the lower branch of the spherical pressure vessel at high mode numbers. The results also indicate that the ratios of the nonlinear natural frequencies of the lower to upper branches decrease when the vibrational modes increase.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-24T08:00:00Z
      DOI: 10.1142/S0219455422500778
       
  • A Unified Transient Vibration Analysis of FGM Sandwich Plates in Thermal
           Environment Based on a Further Refined Zigzag Plate Theory

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      Authors: Dong Shao, Weige Liang, Wei Wu, YongQiang Tao
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, a simple and unified process is established for transient vibration analysis of functionally graded material (FGM) sandwich plates in thermal environment. The temperature field, considered constant in the plane, is distributed along the thickness with uniform, linear and nonlinear profiles. For the material properties, both temperature and position dependence are taken into account. A further refined zigzag plate theory accounting for partitioned transverse displacements and piecewise-continuous in-plane displacements is developed within the framework of Hamilton’s principle including thermal effects. Appropriately and simplicity representation of the deformation states is provided in the governing equations. A spectral analysis technique, namely, method of reverberation ray matrix (MRRM), is employed to calculate the transient vibration responses of FGM sandwich plates with general boundary conditions and arbitrary external loadings. The artificial spring technology and the equivalent wave source vector are introduced to improve the numerical stability and parametric adjustability of MRRM. The accuracy, flexibility and efficiency of the proposed process are discussed using many numerical examples. On this basis, the effects of the boundary parameters, FGM gradient index, core-to-facesheet thickness ratio, thermal properties and external loadings on the transient vibration behaviors of FGM sandwich plates are thoroughly investigated.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-23T08:00:00Z
      DOI: 10.1142/S021945542250095X
       
  • Influence of Refined Wind Load Parameters and Wind-Loading Mode on
           

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      Authors: Zhibin Tu, Jianfeng Yao, Haiwei Xu, Weijun Zhong, Wenjuan Lou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study aims to investigate refined wind load parameters on main rods and the influence of wind-loading mode on wind-induced responses of the angle-steel transmission tower. The wind load parameters discussed in this study include drag coefficients, wind load distribution factors and skewed wind load factors. To achieve the aim, wind tunnel tests were conducted to explore aerodynamic loads for integrated frame, single frame, and main rod models of cross-arm and tower body. The wind load parameters of the different models were investigated. In addition, a series of wind-induced vibration simulation was applied to examine the wind-induced responses of an ultra-high voltage (UHV) transmission tower with a long cross-arm under concentrated and distributed wind loads. The simulated results under the two types of wind loads were compared. The results show that the longitudinal drag coefficients of the main rods are smaller than the values of the integrated frame, and equivalent on average to the values of the single frame. The experimental shielding factor of the cross-arm is larger than those in different standards due to the joint drag effects of leeward, upper, and lower faces of the cross-arm in the wind tunnel test. The experimented shielding factor of the tower body is in line with those referring to the Chinese and AS/NZS standards, and slightly larger than those based on the British and JEC standards. The skewed wind load factors of the main rod models are quite different from other models for cross-arm and tower body. The wind-induced vibration simulation suggests that, the wind-loading mode has limited impact on the displacements, accelerations, and gust factors of the transmission tower, but significantly influences the maximum normal stresses (MNSs) of the rods’ cross-sections. The MNSs caused by the distributed wind loads are obviously greater than those caused by concentrated wind loads, especially for the rods at the two ends of the cross-arm.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-21T08:00:00Z
      DOI: 10.1142/S0219455422500742
       
  • Nonlinear Resonance of Functionally Graded Porous Circular Cylindrical
           Shells Reinforced by Graphene Platelet with Initial Imperfections Using
           Higher-Order Shear Deformation Theory

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      Authors: M. Salehi, R. Gholami, R. Ansari
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper uses the higher-order shear deformation theory (HOSDT) to analyze the nonlinear resonance of functionally graded graphene platelet-reinforced porous (FG-GPL-RP) circular cylindrical shell with geometrical imperfections subjected to the harmonic transverse loading. The shell considered is surrounded by the elastic Winkler–Pasternak foundation. Based on Hamilton’s principle, the nonlinear governing equations of motion of the imperfect system considered are established using the first-order and various higher-order shear deformation shell theories that contain a unified higher-order displacement field. Four types of porosity and graphene nanoplatelet distribution patterns are considered. The modified Halpin-Tsai scheme and rule of mixture are utilized to calculate the effective properties of FG-GPL-RP materials. Explicit expressions of the nonlinear primary resonance of imperfect FG-GPL-RP cylindrical shells for simply-supported boundary conditions are achieved by the Galerkin technique and method of multiple scales. After verifying the accuracy of the model used and the results obtained, the influences of the geometric parameters, material properties and distribution and imperfection value on the nonlinear primary resonant response of the imperfect FG-GPL-RP circular cylindrical shells are examined in detail.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-18T08:00:00Z
      DOI: 10.1142/S0219455422500754
       
  • Automatically Extracting Bridge Frequencies Using SSA and K-Means
           Clustering from Vehicle-Scanned Accelerations

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      Authors: Y. B. Yang, Yi He, Hao Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper removes the subjective judgment by proposing a technique for automatically identifying the bridge frequencies using singularity spectrum analysis and [math]-means clustering. First, the vehicle-bridge contact-point acceleration newly derived from is used to avoid the adverse effect brought by vehicle’s frequency. Next, the contact signal is processed by singular spectrum analysis to remove the noises. Then, the first several principal components are processed by the FFT to extract peak frequencies. Finally, the [math]-means clustering algorithm is adopted to group the peak frequencies into clusters, with their centroids denoting the bridge frequencies. They are verified against those extrapolated from the 1st bridge frequency. Moreover, the current technique was assessed by studies on factors including pavement roughness, vehicle velocity, ongoing traffic, and vehicle stiffness, along with a field test on a bridge to demonstrate its capability. One feature of the current method is that the errors for higher frequencies predicted are not higher than lower frequencies.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-18T08:00:00Z
      DOI: 10.1142/S0219455422500791
       
  • Influence of Initial Guy Tension and Antenna Masses in the Sensor Layout
           for Dynamic Characterization of Guyed Masts

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      Authors: Bruno Clavelo Elena, Patricia Martín Rodríguez, Vivian Elena Parnás
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Sensitivity analysis plays an important part in the validation of a sensor layout for the identification of the dynamic response of a system. Although sensitivity analysis has been implemented for this purpose in several civil engineering structures, there are still uncertainties in the case of more complex, nonlinear systems, such as guyed masts, where small changes in mass or stiffness can result in large variations of the general dynamic behavior. This paper describes the influence of antenna masses and initial guy tension variation in the total number and position of sensors required to assess the dynamic response of tall guyed mast telecommunication towers. For the study, the computational models of four different guyed masts were generated and a sensor layout was obtained for each model using a sensitivity analysis. Then, the proposed sensor layouts were verified for different initial guy tensions and total antenna mass of the system, by means of the Modal Assurance Criterion. The principal finding is that initial guy tension presents the highest influence on the variation of correspondence values between mode shapes, with modifications of these values in up to [math]. This finding suggests that a preliminary sensor layout based on information provided by a computational model or structural drawings of a guyed mast may be rendered inefficient if there is variation in guy tension due to construction errors or relaxation of cables.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-18T08:00:00Z
      DOI: 10.1142/S0219455422500821
       
  • Wind-Induced Response Control of a Television Transmission Tower by
           Piezoelectric Semi-Active Friction Dampers

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      Authors: Jingbo Wu, Bo Chen, Xinxin Song
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To be a typical flexible structure with small damping, a high-rise television (TV) transmission tower is sensitive to wind excitations. The response control of TV transmission towers by semi-active friction dampers under strong external excitations is still very limited and the parametric study on control performance has not been systematically investigated. To this end, the semi-active control of a wind-excited TV transmission tower by piezoelectric friction dampers is conducted in this study. A fine finite element (FE) model of a real TV transmission tower is constructed and then a two-dimensional (2D) dynamic model is also established. The analytical model of a semi-active friction damper based on piezoelectric actuators is then established with damper stiffness considered. The equations of motion of the tower with friction dampers are then established. The local feedback control algorithm based on nonlinear Reid damping mechanisms is used to command piezoelectric friction dampers for wind-excited towers. A high-rise TV transmission tower in China is used to investigate the validity of the proposed semi-active control approach and compared with that of passive control. Furthermore, a detailed parametric investigation is conducted to examine the influence of gain coefficient, damper stiffness, hysteresis loops, damper force, and wind loading intensity on control efficacy. The analytical results indicate that piezoelectric friction dampers with optimal parameters are beneficial to the vibration mitigation of TV transmission towers under different wind loading intensities.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-17T08:00:00Z
      DOI: 10.1142/S021945542250064X
       
  • Nonlinear Large-Amplitude Oscillations of PFG Composite Rectangular
           Microplates Based Upon the Modified Strain Gradient Elasticity Theory

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      Authors: Jiafeng Chu, Yanzhao Wang, Saeid Sahmani, Babak Safaei
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this research work, the nonlinear large-amplitude free vibration characteristics of composite microplates made of a porous functionally graded (PFG) material are addressed numerically in the presence of different size-dependent strain gradient tensors as microscale. Accordingly, for the first time, the effect of each microstructural tensor is analyzed separately on the nonlinear free oscillations of PFG microplates with and without a central cutout. In order to fulfill this goal, the isogeometric computation approach is engaged to integrate the finite element approach into the nonuniform B-spline-based computer aided design tool. Accordingly, the geometry of the microplate with a central cutout is modeled smoothly to verify C[math] continuity based upon a refined higher-order plate formulations. In this regard, the microstructural-dependent frequency responses associated with the nonlinear free oscillations of microplates are traced. In both the cases of simply supported and clamped boundary conditions, it was revealed that the fundamental frequency is enhanced about 1.20% by considering only the symmetric rotation gradient tensor, about 3.27% by taking only the dilatation gradient tensor, and 9.43% by considering only the deviatoric stretch gradient tensor. On the other hand, the anisotropic character of PFG composite microplates results in an unsymmetrical frequency response curve, as the nonlinear frequencies associated with negative oscillation amplitudes are a bit higher than those of positive ones.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-17T08:00:00Z
      DOI: 10.1142/S0219455422500687
       
  • Overturning Resistance of Friction Pendulum Bearing-Isolated Structure
           Subjected to Impact

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      Authors: Jingcai Zhang, Yong Ding, Xinchun Guan
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Friction pendulum bearing (FPB) shows superior performance in reducing dynamic responses of structures under earthquakes. Though the seismic response of the FPB-isolated structure is well understood, its overturning resistance caused by limited permissible displacement under impact is rarely studied. This paper presents an evaluation and parametric study on the overturning resistance of the FPB-isolated structure under impact, using particularly the coefficient of overturning resistance to evaluate the overturning resistance of the isolated structure. The capacity of the overturning resistance of FPB-isolated structure as well as the seismic response when the isolated structure subjected to pluse-like and no-pluse-like earthquake records were addressed. The influence of various key factors, including the vertical component of impact force, displacement ratio, properties of the FPB, peak ground acceleration (PGA), and mass ratio of the isolation storey, is investigated to give an insight into the potential overturning risk of the entire structure. The results indicate that the overturning resistance of the FPB-isolated structure will be reduced significantly due to the presence of impact. The overturning stability depends mainly on the displacement ratio, impact stiffness, PGA, friction coefficient, and equivalent radius of the FPB, but the mass ratio of the isolation storey shows limited influence on the overturning resistance of the FPB-isolated structure under impact.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-17T08:00:00Z
      DOI: 10.1142/S0219455422500729
       
  • Optimum Design of Single and Multiple Tuned Mass Dampers for Vibration
           Control in Buildings Under Seismic Excitation

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      Authors: Francisco da Silva Brandão, Alex Koch de Almeida, Letícia Fleck Fadel Miguel
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents a study on optimization of design parameters and positions of single tuned mass damper (STMD) and multiple tuned mass dampers (MTMDs), used as vibration control systems in buildings under seismic excitations aiming to reduce their story drift. As case studies, three buildings are subjected to three real earthquakes and one non-stationary artificial earthquake, and their responses are analyzed. For each building, different control scenarios are proposed and to run the optimizations, the whale optimization algorithm (WOA) was used. The results showed that for Building 1, the Scenario 1-Optimized, with a STMD at the top floor, was the best alternative. In Building 2, the Scenario 1-Optimized, with also a STMD at the top floor, proved to be the best solution. Finally, for Building 3, the Scenario 4-Modified, with 3 TMDs arranged in the building elevation plane was the only one that had effective control of structural response, therefore, it is the best control scenario.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-17T08:00:00Z
      DOI: 10.1142/S021945542250078X
       
  • Experimental and Analytical Study on the Penetration Depth of Mortar
           Targets Subjected to Projectile Impact in the Hypervelocity Regime

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      Authors: Fei Gao, Chunming Song, Gan Li, Guokai Zhang, Shuxin Deng, Zhen Wang, Chenkang Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A projectile may be deformed and eroded due to the high pressure generated by hypervelocity penetration, which makes it difficult to describe the penetration mechanism for protection engineering by existing theories at such high velocities. To analyze the penetration depth of concrete-like targets subjected to hypervelocity impact by kinetic energy weapons, experiments with ogive-nosed steel projectiles penetrating mortar targets are conducted, where the average uniaxial compressive strength of the mortar targets is 41.8[math]MPa and the impact velocities range from 1[math]225[math]m/s to 2[math]392[math]m/s. The experimental results show that the crater diameter and crater depth have a linear relationship with the striking velocity. The depth of penetration (DOP) increases linearly first and then decreases sharply and increases slowly again. Three penetration regimes are observed in turn with increasing velocity, i.e. rigid projectile penetration, abrasive projectile penetration and semifluid projectile penetration. Furthermore, based on a study of the dynamic compression behavior and penetration resistance function of concrete, a hydroelastoplastic-frictional penetration model is established. The velocity range is divided into solid penetration, semifluid penetration and fluid penetration, which correspond to [math], [math] and [math], respectively. Then, the rigid and abrasive projectile penetration models, which consider the projectile mass loss, are verified by the present test data. Finally, the semifluid projectile penetration model is evaluated with the existing test data. These results can provide support for research on the damage effect of hypervelocity kinetic energy weapons and the design of underground strategic protection engineering.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-11T08:00:00Z
      DOI: 10.1142/S0219455422500699
       
  • Study of a Novel Nonlinear Viscoelastic Bio-Inspired Multi-Dimensional
           Vibration Isolation Device

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      Authors: Zhen-Hua He, Zhao-Dong Xu, Jian-Yang Xue, Xing-Jian Jing, Yao-Rong Dong, Qiang-Qiang Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes a novel viscoelastic bio-inspired multi-dimensional vibration isolation device (VBM-VI). The viscoelastic (VE) damper and the limb-like-structure (LLS) are first installed into the vibration device to make it simultaneously reveal excellent vibration isolation performance at three directions. First, the dynamic equations of the proposed device are established, and the significant coupling nonlinear characteristics caused by material and geometric factor together are discussed. Then, the harmonic balance method (HBM) is used to solve the nonlinear dynamic equation, and the geometrical parameters of the VE damper and LLS device are studied to assess the influence of coupling nonlinear characteristic on the vibration isolation performance. The results indicate that the coupling nonlinear characteristics have an excellent advantage on vibration control, and the proposed VBM-VI device can achieve different vibration isolation performances by adjusting the parameters of the VE damper or LLS. The study also shows that the vibration isolation performances at the horizontal and vertical directions are coupled and restricted with each other, showing different levels of sensitivity to parameter variation. Finally, a comparative study is performed between the traditional vibration isolation device (TV-VI) and the VBM-VI device, indicating that the coupling nonlinear characteristic caused by the VE damper and LLS possesses remarkable advantage of improving the vibration isolation performance of the VBM-VI device.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-10T08:00:00Z
      DOI: 10.1142/S0219455422500705
       
  • Natural Vibrations of a Cylindrical Shell with Fluid Partly Resting on a
           Two-Parameter Elastic Foundation

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      Authors: Sergey A. Bochkarev
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents the results of studies on natural vibrations of circular cylindrical shells containing liquid and resting on an elastic foundation, which is described by the Pasternak two-parameter model. In the meridional direction, the elastic medium is nonuniform and represents an alternation of sections in which the foundation is present or absent. The behavior of the elastic structure and the compressible fluid is described in the framework of classical shell theory based on the Kirchhoff–Love hypothesis and the Euler equations. The equations of motion of the shell are reduced to a system of ordinary differential equations with respect to new unknowns. The wave equation written for pressure in the fluid also reduces to a system of ordinary differential equations using the straight line method. The solution of the formulated boundary value problem is found by the Godunov orthogonal sweep method. The validity of the results obtained is confirmed by comparison with the known numerical-analytical solutions. The dependences of the minimum vibration frequencies on the characteristics of elastic medium with variable nonuniformity along the length of the structure have been obtained for cylindrical shells with different boundary conditions. It has been found that the violation of smoothness of the derived dependences is caused by a change of the vibration mode with minimum frequency and is determined both by the ratio of the size of the elastic foundation to the entire length of the shell and its stiffness, and also by a combination of boundary conditions set at the edges of the thin-walled structure.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-10T08:00:00Z
      DOI: 10.1142/S0219455422500717
       
  • Frequency Comb Free Vibration Behavior of a Single-Span Plate Pumped by
           Low-Speed Moving Inertial Loads

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      Authors: Zhi Sun
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Structures carrying moving loads present rich vibration phenomena and colorful spectrum characteristics. This study analytically investigates the moving-inertial-load-pumped frequency comb free vibration behavior of a single-span rectangular linear elastic Kirchhoff thin plate in the low-speed region. Multiple-time-scales expansion is made and the asymptotic solution describing the non-resonance modal oscillation is derived. Case studies on a single-span rectangular isotropic plate with the clamped opposite boundaries dominated by the first two transverse flexural modes are presented. Numerical computation based on finite element method structure modeling and response numerical integration verifies the modal frequency comb characteristics as predicted by the proposed theoretical model. The results also present the weak modal interaction for the studied single-span structure in the observed light-mass low moving speed region. The outcomes of this study will benefit the related structural dynamic system design and intervention.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-09T08:00:00Z
      DOI: 10.1142/S0219455422500328
       
  • Elastic Buckling and Free Vibration of Functionally Graded Piezoelectric
           Nanobeams Using Nonlocal Integral Models

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      Authors: Yanming Ren, Hai Qing
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Previously it was shown that nonlocal piezoelectric differential models will lead to inconsistent bending response for Euler–Bernoulli beams under different loadings and boundary conditions. In this paper, the general strain- and stress-driven two-phase local/nonlocal integral piezoelectric models are applied to analyze the elastic buckling and free vibration of functionally graded piezoelectric (FGP) Euler–Bernoulli beams under different boundary conditions. The differential governing equations and standard boundary conditions are derived by the Hamilton’s principle. The relations between the general strain and general nonlocal stresses are expressed as integral equations, which are further transformed equivalently to differential forms with constitutive boundary conditions. Several nominal variables are introduced to simplify the differential governing and constitutive equations, as well as the standard and constitutive boundary conditions. The general differential quadrature method is applied to obtain the numerical results of buckling loads and vibration frequencies of the FGP Euler–Bernoulli beam. Numerical results show that general strain- and stress-driven two-phase local/nonlocal integral piezoelectric models will lead to consistently softening and toughening size-dependent responses, respectively.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-09T08:00:00Z
      DOI: 10.1142/S021945542250047X
       
  • Spectral Model of Offshore Wind Turbines and Vibration Control by Pendulum
           Tuned Mass Dampers

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      Authors: Gino Bertollucci Colherinhas, Marcus Vinicius Girão de Morais, Marcela Rodrigues Machado
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Offshore wind turbines (OWTs) are complex systems that may experience excessive vibrations due to winds, waves, rotor torque, or seismic loads during the operation. Tuned mass dampers (TMDs) have been a widely used vibration passive control device in structures, including wind turbines. The TMD works as a damper that transfers the kinetic energy from the main structure to a secondary mass usually attached to the hub. The spectral element method (SEM) is suitable for analyzing dynamic structural problemss with accuracy and low computational cost. This paper presents a monopile wind turbine fitted with a pendulum-TMD (PTMD) modeled by spectral elements. An optimum pendulum design is performed through the genetic algorithm technique. The wind turbine selected is a National Renewable Energy Lab (NREL) monopile 5[math]MW baseline wind turbine fitted with a PTMD, subjected to winds and waves simulated as random spectra in the analysis. Numerical results show the efficiency of the proposed spectral model and the optimum PTMD design for the OWT under random excitation.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-09T08:00:00Z
      DOI: 10.1142/S0219455422500535
       
  • Dynamic and Energetic Characteristics Comparison of a Tri-Stable Vibration
           Absorber and Energy Harvester Using Different Permanent Magnet Arrays

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      Authors: Xi Wang, Zhenyuan Xu, Dida Wang, Tao Wang, Guoqiang Fu, Caijiang Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, it has been demonstrated that the tri-stable energy harvesters are more efficient than the bi-stable and mono-stable harvesters in energy harvesting. The oscillators of energy harvesters can be designed as a vibration absorber to attenuate the vibration of the primary system. This paper presents a combined vibration absorber and energy harvester (VAEH) system for simultaneous vibration control and energy harvesting, and the dynamic performances of the VAEH with two magnet arrays of the same geometric parameters, but opposite polarity external magnets, are studied. The mathematical model of the tri-stable VAEH is established, by which the dynamic and energetic characteristics of the VAEH system are obtained. It is found that the potential barrier and potential well depth of the repulsive magnet array are greater than the attractive one, reducing the voltage harvesting efficiency under harmonic and impulsive excitation. Both the amplitude and frequency of excitation are crucial to the dynamic response of the VAEH system. The attractive VAEH performs better than the repulsive VAEH in vibration suppression, especially for high impulse input. From the frequency response of the system, the vibration of the primary system is shown to be magnified at certain frequencies. The magnified primary system vibration and the harvested voltage can be attenuated by increasing the VAEH damping, which is a critical parameter to balance the weight of vibration suppression and energy harvesting. The attractive VAEH designed in this paper performs better than the repulsive one in vibration suppression and energy harvesting.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-09T08:00:00Z
      DOI: 10.1142/S0219455422500626
       
  • A Double-Rail Phononic Crystal Model for the Ballasted Track

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      Authors: Yuxiong Liang, Qingsong Feng, Jianfei Lu, Wenjie Guo, Zhou Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To investigate the properties of elastic waves propagating in the periodic ballasted track, a double-rail phononic crystal (DRPC) model which consists of two parallel rails fastened on equally spaced sleepers supported by ballast is proposed in this study. The presented numerical results show that there are twelve characteristic waves occurring in the DRPC. These waves can be divided into three kinds. Within the calculated frequency range, the first kind of characteristic wave always propagates except an initial lower frequency range. The second kind of characteristic wave has alternative pass bands and stop bands, showing obvious phononic property of the DRPC. The wavenumbers of the third kind of characteristic wave have larger imaginary parts, implying that this kind of wave is evanescent wave and can only propagate a few spans of the track away from the source. The numerical results show more advantages of the DRPC for explaining the elastic wave propagation mechanism in the ballasted track than the single-rail phononic crystal (SRPC) model.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-07T08:00:00Z
      DOI: 10.1142/S0219455422500663
       
  • Stability Analysis for Spatial Autoparametric Resonances of Framed
           Structures

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      Authors: Wei Liu, Bin Zhang, Chao Shen, Yu-Chun Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The spatial dynamic instabilities of framed structures due to autoparametric resonances have been seldom investigated in the published literature. Based on the finite element method (FEM), the spatial parametric vibration equations are established for general framed structures. The Newmark’s method and the energy-growth exponent (EGE) are used to determine the stability of the spatial autoparametric resonances of framed structures. A portal frame model is used to conduct a spatial (out-of-plane) autoparametric resonance experiment. The numerical results of the autoparametric resonances are found to agree with those of the test, which proves the validity of the present theoretical formulation. A numerical example for autoparametric resonance stability analysis of a spatial frame is presented to firstly predict the three instability modes of autoparametric resonances, i.e. global unidirectional translational instability, bidirectional (diagonal) translational instability and torsional instability. When the excitation frequency is approximately twice the modal frequency of spatial vibration of a framed structure, spatial dynamic instability will occur due to autoparametric resonance. A small excitation force can cause a strong autoparametric resonance of the framed structure. The potential risk of spatial dynamic instability is revealed for the framed structures under periodic loads.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-02-04T08:00:00Z
      DOI: 10.1142/S0219455422500651
       
  • Prediction of Thermal-Induced Buckling Failures of Ballasted Railway
           Tracks Using Artificial Neural Network (ANN)

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      Authors: Chayut Ngamkhanong, Sakdirat Kaewunruen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper investigates the possibility for implementing machine learning-aided prediction in analyzing the buckling phenomena of ballasted railway tracks induced by extreme temperature. In this study, artificial neural networks (ANNs) have been developed to identify the relationship between various ballasted track conditions and outputs, namely safe temperature and buckling temperature. The variables included in the objective function of the optimization problems are the lateral resistance of ballasted track provided by ballast-sleeper interaction, torsional resistance provided by fastening systems, and misalignment of the track. Due to its complexity in parameter combinations, the objective of this study is to create predictive models with the aim of minimizing the usage of scarce resources. Thus, this paper is the first to develop a novel machine learning-aided prediction of railway track buckling due to extreme temperature. Comprehensively, all 353 datasets of the safe and buckling temperatures derived from previous finite element (FE) simulation results have been collected and trained. Note that the mean squared error (MSE) and the coefficient of determination ([math] are considered to quantify the performance of the ANN architectures. The optimal ANN architecture with a very high rate of accuracy has been determined and highlighted. Thus, the suggested neural network model can be applied conveniently to help estimate safe and buckling temperatures of the complex track models in order to improve track conditions and thus prevent track buckling in summer.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-27T08:00:00Z
      DOI: 10.1142/S0219455422500493
       
  • Vibration Suppression of the Viscoelastic Sandwich Doubly-Curved Shells
           Using Magnetostrictive Layers Subjected to Kerr’s Foundation

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      Authors: Caiyuan Xiao, Guiju Zhang, Peisi Hu, Yudong Yu, Youyu Mo, Reza Mohammadi
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This research presents a novel model to examine the vibration and deflection analysis of the visco-magnetostrictive doubly-curved sandwich shell subjected to Kerr’s foundation. The shell has a homogenous core with two magnetostrictive layers and two viscoelastic faces. A velocity feedback control process is applied to reduce the vibration of the system using an active strategy. In the present model, active (magnetostrictive materials) and passive (viscoelastic materials) strategies are applied together to suppress the vibration of the sandwich shell. Simple sinusoidal deformation theory (SSDT) is dedicated to inspecting the shear impacts along with the thickness of the sandwich shell. Hamilton’s axiom and Kelvin–Voigt relation are dedicated to achieving the governing equations of motion. Then, the Navier solution technique is dedicated to deriving the eigenfrequency of the sandwich shell with simply-supported (S-S) boundary conditions. The results indicate that the present model can improve the vibration reduction of the curved structures by using the amalgamation of the passive and active strategies. Also, the application of Kerr’s foundation has a major impact on the vibration reduction of the system.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-27T08:00:00Z
      DOI: 10.1142/S0219455422500584
       
  • Joint Damage Identification in Frame Structures by Integrating a New
           Damage Index with Equilibrium Optimizer Algorithm

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      Authors: Seyed Bahram Beheshti Aval, Pooya Mohebian
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Beam-column joints are responsible for maintaining the integrity and stability of frame structures, and any damage to these critical components can endanger the overall safety and reliability of the structure. Hence, early detection of structural joint damage is of paramount importance. However, most of the available structural damage identification methods focus on identifying damage in structural members, and relatively fewer methods have been developed so far for assessing damage in structural joints. In view of this, the present study proposes a new two-stage method for joint damage identification of frame structures. In the first stage, an efficient damage indicator, called residual moment-based joint damage index (RMBJDI), is developed and applied to detect the location of potentially damaged joints. This damage indicator can help to reduce the number of involved damage variables by excluding healthy joints from the problem. In the second stage, the reduced dimension damage identification problem is formulated as an optimization problem and is further tackled by employing a robust meta-heuristic algorithm, namely equilibrium optimizer (EO), to determine the damage severity of suspected damaged joints. In order to assess the capability and effectiveness of the presented joint damage identification method, two numerical examples of frame structures are conducted under both noise-free and noisy conditions. The results demonstrate that the proposed two-stage method, which integrates RMBJDI with EO, is a highly accurate and powerful tool for localizing and quantifying the joint damage in frame structures.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-26T08:00:00Z
      DOI: 10.1142/S0219455422500560
       
  • Out-of-Plane Free Vibration Analysis of Continuous Curved Girders with
           Combined Linetypes Using Differential Quadrature Element Method

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      Authors: Guangjun Sun, Hongjing Li, Tong Wang, Qiang Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this study, the out-of-plane free vibration equations of circular curved and clothoid transition curved girders with various boundary conditions were derived. The continuous curved girder with combined linetypes was discretized into separate curved girder elements. Based on the differential quadrature element method (DQEM), the Chebyshev–Gauss–Labatto unequal mesh division was applied to discretize the vibration equations of the continuous curved girder into those of the curved girder elements, along with the boundary conditions, internal geometric compatibility conditions, and force balance conditions. The out-of-plane natural frequency equations were derived considering the boundary conditions by the substitution method. The free vibration was solved for continuous curved girders with combined linetypes of circular and clothoid transition curves. The effectiveness of the DQEM was verified, and the effect of the number of grid points on the accuracy of the solution was evaluated. In addition, the effects of the bending/torsional stiffness ratio, warping coefficient, and boundary conditions on the natural frequencies of continuous curved girders with combined linetypes were investigated. The results showed that the DQEM can be efficiently used to solve the free vibration of multispan continuous curved girders with various linetype combinations. The frequencies of the continuous curved girder with combined linetypes decrease with the weakening of boundary constraints, but increase with increasing warping coefficient and bending/torsional stiffness ratio.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-24T08:00:00Z
      DOI: 10.1142/S0219455422500602
       
  • Hybrid Isolation Strategy for Seismically Isolated Multi-Tower Building
           with a Large Podium

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      Authors: Shangrong Zhang, Yuchen Hu, Xinyu Liu, Ping Tan, Xiangjun Guo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The Compositive Passive Control method (CPC method) of “interlayer seismic isolation”[math][math][math]“shock absorption between adjacent towers” is applied to Multi-Tower Building (MTB) with a large podium. Taking the total vibration energy of the structure as the optimal control objective, the response expressions of a multi-DOF layer shear model and an equivalent single-DOF layer shear model are derived. The rationality of the equivalent model is demonstrated from the perspective of mode characteristics and time history response. Based on the Kanai–Tajimi spectral seismic motion model, the control effect and the optimal control parameters of the CPC method are studied. Compared with the conventional seismic scheme and the interlayer seismic isolation scheme, the influence of the CPC method on the structure natural vibration characteristics and dynamic response under different parameters of the connecting control device is discussed and analyzed. The numerical analysis proves that the CPC method provides a significant damping effect compared with the interlayer seismic isolation scheme. It maintains the advantages of the interlayer seismic isolation scheme and reduces the defect of the response amplification caused by the interlayer isolation. This analysis constitutes a good reference for the follow-up study of the CPC method of MTB.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-24T08:00:00Z
      DOI: 10.1142/S0219455422500614
       
  • Effect of Porosity on the Thermal Buckling Analysis of Power and Sigmoid
           Law Functionally Graded Material Sandwich Plates Based on Sinusoidal Shear
           Deformation Theory

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      Authors: Supen Kumar Sah, Anup Ghosh
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This work examines the effect of porosity distributions on thermal buckling analysis of functionally graded material (FGM) sandwich plates. To consider the porosity effect, five different types of distribution models, even, uneven, logarithmic uneven, linear uneven, and sinusoidal uneven are considered. It is assumed that the FGM faces of the sandwich plate are porous while the ceramic core is nonporous. To investigate the thermal buckling behavior of porous FGM sandwich plates, four different types of thermal loads, such as uniform, linear, nonlinear, and sinusoidal temperature rise along the thickness direction are considered. Effective material properties and thermal expansion coefficients of FGM sandwich plates are evaluated based on Voigt’s micromechanical model considering power law FGM (P-FGM) and sigmoid function FGM (S-FGM). The analytical solution is carried out using Hamilton’s variational principle considering the von Karman nonlinearity. The equilibrium and stability equations are derived based on sinusoidal shear deformation theory (SSDT). Numerical results are obtained to observe the influence of different porosity distributions, porosity coefficients, thermal loadings, and geometrical parameters over critical thermal buckling temperature.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-24T08:00:00Z
      DOI: 10.1142/S0219455422500638
       
  • Parametric Instability of Rotating Functionally Graded Graphene Reinforced
           Truncated Conical Shells Subjected to Both Mechanical and Thermal Loading
           Conditions

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      Authors: X. Li, W. T. Jiang, X. C. Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This article focuses on parametric instability of rotating functionally graded (FG) truncated conical shells reinforced by graphene platelets (GPLs) and subjected to both mechanical and thermal loading conditions. The GPL nanofillers are uniformly dispersed in each concentric conical layer but its weight fraction varies continuously along thickness direction, which induces the position-dependent effective material properties. Based on Love’s thin shell theory and Galerkin approach, the equations of motion for the conical shells are derived with the effects of the periodic axial loads, thermal expansion deformation, rotation-induced initial hoop tension, gyroscopic and centrifugal forces taken into account. Then, the parametric instability under combination parametric resonance for the conical shells is performed by the method of multiple scales, and the analytical solutions of both instability boundaries are obtained. A comprehensive parametric study is conducted which focuses on instability regions and vibration characteristics of the conical shell. Of particular interest in this process is the combined effect of the rotation, dynamic loads and thermal effects on dynamic stability of FG-GPL reinforced truncated conical shells.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-24T08:00:00Z
      DOI: 10.1142/S0219455422500675
       
  • Effect of a “Slight” Curvature of the Axis of a Thin-Walled
           Nonprismatic Beam on its Free Vibration

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      Authors: Józef Szybiński, Piotr Ruta
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper presents an analysis of the effect of a “slight” curvature of the axis of a thin-walled beam on its eigenfrequencies and forms. By “slight” we understand such a beam curvature at which no theory of curved beams (arches, horizontally curved girders), but classical beam theory is applied. The subject of the analysis is the open nonprismatic thin-walled beams with any geometrical parameters, and prismatic beams. The thin-walled beam model used in the analysis was derived on the basis of the momentless theory of plates, using the Vlasov assumptions. The free vibrations of the beams were analysed. Calculations were performed for four groups of beams. Each of the groups comprised two beams with the same configuration of flanges and identical geometrical cross section characteristics, but differing in web geometry. One of the beams had a symmetrical web (a beam with a rectilinear axis in the web plane), whereas the web of the other beam was asymmetrical (a beam with its axis curved in the web plane). The algorithm based on Chebyshev polynomials was used to solve the variable coefficient equations describing the model’s vibration. According to this algorithm, solutions are sought in the form of Chebyshev series and the closed analytical recurrence formulas generated by the algorithm are used to calculate the coefficients of the equations. It has been shown that even a “slight” curvature of the beam’s axis has a significant effect on its eigenfrequencies and forms, as confirmed by a comparison of the results with the ones obtained using Finite Element Method (FEM).
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-22T08:00:00Z
      DOI: 10.1142/S0219455422500432
       
  • Modeling the Multi-Phased Hysteretic Friction Behavior of Aluminum
           Foam/Polyurethane Interpenetrating Phase Composites Damper

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      Authors: Shaobo Liu, Aiqun Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Aluminum foam/polyurethane (AF/PU) interpenetrating phase composites damper is a multi-phased hysteretic friction damper, which has a high potential for application to mitigating the seismic responses of building structures. In this paper, the hysteretic responses of the AF/PU composites damper subjected to different loading displacement amplitudes and loading cycles were experimentally investigated, and the main characteristics of the multi-phased hysteretic friction responses are assessed. According to the hysteretic responses of the AF/PU composites damper, a new model that is featured by a hysteresis mechanism, a nonlinear spring and a damping dashpot in parallel is constructed. Through the sensitivity analysis of relevant parameters, the optimum model is obtained and its main basic parameters ([math]) are identified using the Universal Global Algorithm of the First Optimization software. The relationships of the main basic parameters with the loading displacement amplitude and loading cycle are then established. By the comparisons with the experimental results, it is validated that the proposed optimum model has an adequate capacity to capture and predict the important features of the multi-phased hysteretic friction characteristics under the various loading displacement amplitudes and loading cycles.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-22T08:00:00Z
      DOI: 10.1142/S0219455422500596
       
  • Vibration Analysis of an In-Pipe Inspection Robot Considering
           Fluid-Structure Coupling

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      Authors: Hang Zhang, Mengqi Gao, Zhenlin Li, Qibing Wu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A fluid drive in-pipe inspection robot is an essential device for the inner inspection of long-distance oil and gas pipelines. Obstacles such as dents and welds can significantly affect the operation stability of the robot as well as the accuracy of inspection. In this paper, a dynamic model is created to investigate the vibrational response of an in-pipe inspection robot moving through a dented pipe. A mechanical model of the polyurethane sealing disc is established based on the Kelvin spring damping model to simulate its bending deformation. Using the simplified model of the in-pipe inspection robot, the axial vibration equation of the robot is analyzed in detail. Furthermore, a dynamic simulation of the virtual prototype of the in-pipe inspection robot is conducted using the MSC/ADAMS software, considering the interaction between the fluid and the structure. Then, the effects of the robot’s speed, sealing disc interval, and dent height on the vibration response during the pigging are examined. The results indicate that the faster the in-pipe inspection robot passes over the pipe dents, the higher the axial vibration generated by the robot, while the time needed for returning to the stable state is shorter. The pitch vibration caused by the dent substantially intensifies with an increase in the sealing disc interval. The axial and pitch vibration caused by the dent intensify significantly with increasing the dent height. The results obtained herein should prove useful to the optimization of the structural design and precise positioning of the in-pipe inspection robot.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-21T08:00:00Z
      DOI: 10.1142/S0219455422500559
       
  • Orthogonal Polynomials-Ritz Method for Dynamic Response of Functionally
           Graded Porous Plates Using FSDT

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      Authors: C. Yu, Z. Meng, X. Zhang, S. Li, W. Xu, C. Chiu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This work focuses on the dynamic response of the functionally graded porous (FGP) plates. To construct the FGP plate model, the material-distributed profiles of the FGP plates are given first. In addition, the relations between the stress and strain are given by means of the first-order shear deformation theory (FSDT). Furthermore, the boundary conditions are defined based on the virtual spring technique. Moreover, the third kind of Chebyshev orthogonal polynomials are employed to construct the displacement components of the FGP plate, and the energy expressions of the FGP plate are constructed and then changed into the Lagrange equation form. Ultimately, the FGP plate energy expressions are solved by means of the Rayleigh–Ritz method. On this basis, the verification of the proposed method is conducted, and then, a series of investigations are given with respect to diverse influence factors.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-21T08:00:00Z
      DOI: 10.1142/S0219455422500572
       
  • Bayesian Operational Modal Analysis with Genetic Optimization for
           Structural Health Monitoring of the Long-Span Bridge

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      Authors: Jianxiao Mao, Chaoyong Yang, Hao Wang, Yiming Zhang, Huan Lu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Modal parameters, including natural frequencies, damping ratios, and mode shapes, are vital for evaluating the in-service condition of long-span bridges subjected to performance degradation or damages. Operational modal identification techniques requiring only ambient vibration responses are usually utilized to identify the modal parameters of in-service bridges. Due to the measurement incompleteness and modeling errors, uncertainties would inevitably be involved in the identification. The changing operational loads of long-span bridges, e.g. vehicles and winds, could also increase uncertainties. These uncertainty factors could decrease the precision of the operational modal identification and undermine the reliability of structural health monitoring (SHM) for long-span bridges. This study introduces an improved Bayesian modal identification approach using the scaled Fast Fourier Transform data for uncertainty quantification. The proposed method integrates the genetic optimization with the posterior probability density function of modal parameters to ensure the accuracy and robustness of the iteration process. Additionally, an asymptotic estimate interval with the assumption of a high signal-to-noise ratio is defined to improve the computational efficiency. The acceleration responses from a numerical example and a full-scale long-span bridge are adopted to validate the performance of the proposed method. Results show that the improved Bayesian approach can accurately identify the modal parameters and efficiently quantify the uncertainties. The method enhances the reliability of modal tracking for SHM of operational long-span bridges.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-20T08:00:00Z
      DOI: 10.1142/S0219455422500511
       
  • Comfort Assessment of Human-Induced Vibration of Pedestrian Bridges Based
           on Stevens Annoyance Rate Model

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      Authors: Pengzhen Lu, Yutao Zhou, Ying Wu, Yu Ding, Jiahao Wang, Yiheng Ma
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In recent years, the continuous innovation in terms of using new materials and structures for pedestrian bridges has led to a significant reduction in the natural frequency of such bridges. Thus, the human-induced vibration comfort of bridges has been increasingly affected. Therefore, this paper introduces the Stevens annoyance rate model (ARM) and proposes a design and evaluation method for human-induced vibration comfort of pedestrian bridges based on this model. In order to verify the effectiveness of the proposed method, a practical pedestrian bridge is used as an example to perform dynamic analysis, comfort evaluation, and vibration reduction design. The results show that the pedestrian bridge comfort evaluation method based on the Stevens-ARM can accurately quantify the vibration comfort of the human body under uncertainties. For comfort control, the new comfort design method and a genetic algorithm (GA) can arrange multiple tuned mass dampers (MTMDs) more reasonably, which can prevent the annoyance rate (AR) and comfort rate under the two-way coupled vibration from exceeding the limit. Moreover, data obtained from 14 pedestrian bridges in China were analyzed to verify the generality and reliability of the findings.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-17T08:00:00Z
      DOI: 10.1142/S0219455422500523
       
  • Shifted Resonance of Railway Bridges Under Trains Passing by Each Other

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      Authors: Ping Lou, J. D. Yau, Francis T. K. Au, S. Urushadze
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Dynamic vehicle–bridge interaction (VBI) plays a crucial role in the train-induced vibrations of a railway bridge for its coupling effects may reduce the bridge response and down-shift the resonant speed. The commonly used nominal theoretical resonant speed ([math] of a typical railway bridge, however, is only related to the bridge frequency ([math] and car length ([math], but it neglects the VBI effects of the moving trains. Such a shifted resonance phenomenon would become significant for a bridge under two trains passing by each other. This study develops a method using an equivalent modal mass to be added onto the bridge to account for the frequency shift due to the presence of multiple train cars for estimation of the shifted resonant speed. The numerical study demonstrates that the proposed method can predict the shifted resonant speed and explain the shifted-resonance phenomenon of railway bridges under train passages.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-17T08:00:00Z
      DOI: 10.1142/S0219455422710018
       
  • Dynamic Stability Analysis of Size-Dependent Viscoelastic/Piezoelectric
           Nano-beam

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      Authors: Zahra Tadi Beni, Yaghoub Tadi Beni
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This paper analyzes the dynamic stability of an isotropic viscoelastic Euler–Bernoulli nano-beam using piezoelectric materials. For this purpose, the size-dependent theory was used in the framework of the modified couple stress theory (MCST) for piezoelectric materials. In order to capture the geometrical nonlinearity, the von Karman strain displacement relation was applied. Hamilton’s principle was also employed to obtain the governing equations. Furthermore, the Galerkin method was used in order to convert the governing partial differential equations (PDEs) to a nonlinear second-order ordinary differential one. Dynamic stability analysis was performed and the effects of such parameters as viscoelastic coefficients, size effect, and piezoelectric coefficient were investigated. The results showed that in this system, saddle points, central points, Hopf bifurcation points, and fork bifurcation points could be created, and the phase portraits connecting these equilibrium points exhibit periodic orbits, heteroclinic orbits, and homoclinic orbits.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-14T08:00:00Z
      DOI: 10.1142/S021945542250050X
       
  • Global Buckling Behavior of CFST Columns with Assembling Errors

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      Authors: Si-Ming Zhou, Jing-Zhong Tong, Gen-Shu Tong, Zhang Lei, Xiang Jiang, Yi-Xiang Liu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Concrete-filled steel tubular (CFST) column has been widely used in engineering practice. In the process of assembling two columns to form a slender member, assembling errors (AE) are inevitably produced at the section of connection. When the AE are too large, the global buckling resistance of slender column would be significantly affected. Therefore, it is necessary to investigate the influence of AE on the stability performance of slender CFST columns. In this study, an axial compressive test involving three CFST columns with AE (AE-CFST columns) was conducted. A refined finite element (FE) model is established for further parametric analysis. Based on a simplified analytical model by analyzing the isolated steel connecting plate, a theoretical formula is proposed for predicting the critical thickness [math] of the connecting plate. When the thickness [math] of the connecting plate meets its requirement, the failure at the section of connection caused by AE could be effectively prevented. Stability design curves considering the influence of AE ratio (the ratio between assembling error and sectional depth of column) are proposed based on numerous FE examples. It is found that the proposed design curves are reliable for the design of AE-CFST columns with different AE ratios.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2022-01-04T08:00:00Z
      DOI: 10.1142/S0219455422500547
       
  • Cable Force Determination Using Phase-Based Video Motion Magnification and
           Digital Image Correlation

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      Authors: Wenbing Chen, Banfu Yan, Jingbo Liao, Lei Luo, You Dong
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The mode shape-aided method provides a simple and effective way for cable force determination, which, however, requires accurate parameter identification of the cable structure. This paper proposes a phase-based video motion magnification to process the image sequences of a cable. Digital image correlations were engaged to measure the dynamic displacement–time history, through tracking the surface characteristic features of the cable. Thereafter, a frequency–domain decomposition technique was applied to extract the natural frequency and mode shape of the cable from the displacement–time history measurements. The identified cable mode shapes, along with a tensioned pinned-pinned cable model, were used to estimate the cable force. The accuracy of the proposed methodology was subsequently verified through laboratory testing on an inclined cable model and field testing on a typical hanger cable of a real-world arch bridge. Overall, the study results indicated that the proposed methodology could expediently and cost-effectively estimate the tension forces of a cable with reasonably acceptable identification accuracy.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-31T08:00:00Z
      DOI: 10.1142/S0219455422500365
       
  • A Simplified Method for Estimating the Critical Wind Speed of Moving
           Vehicles on Bridges Under Crosswinds

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      Authors: Mengjin Sun, Dalei Wang, Xiang Shen, Airong Chen
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To evaluate the crosswind stability (overturning and sideslip) of vehicles driving on the bridge, obtaining critical wind speed is essential. The traditional method is based on the aerodynamic forces of moving vehicles on the bridge and the analysis of force equilibrations. However, various shapes of the bridge make the flow field around the vehicle on the bridge very complicated to obtain. In this paper, a simplified method is introduced to calculate the critical wind speeds of moving vehicles on bridges based on the influence of coefficients of the wind environment on the bridge and the aerodynamic forces of moving vehicles on open fields. The aerodynamic forces of moving vehicles are simulated with dynamic mesh techniques. Besides, the characteristics of the wind environment on the bridge deck are studied to evaluate the driving safety and determine the influence coefficient. To further demonstrate the reliability, critical wind speed in different road conditions of the proposed simplified method shows very good agreement with the traditional method.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-31T08:00:00Z
      DOI: 10.1142/S0219455422500468
       
  • Non-linear Dynamic Analysis on a Continuum Suspension Bridge Model with
           Spatial Layout of Main Cables

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      Authors: Liang Xu, Yi Hui, Ke Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      This study proposes an approach to set up a continuum full bridge model with spatially inclined cables based on the Hamilton principle. The dynamic governing functions, considering the geometric non-linearities of cables and deck, represent simultaneously the vertical motion of deck and vertical–horizontal motion of cable. With the comparison of the modal properties obtained from the model to those from the accurate model, results show that the proposed model is capable of accurately simulating the modal properties. The primary resonance responses and corresponding frequency-response curves are obtained through the multiple-scale-method. A finite element (FE) model is established, and the corresponding non-linear dynamic analysis in time domain is conducted. Comparing the results from two models, it can be checked that the proposed model is reliable. According to the results of the proposed model, it is found that the second-order shape functions (SOSFs) play a significant role in the system response. Once the non-linear vibration of the bridge becomes significant only considering the excited mode with using the classical Galerkin decomposition cannot correctly predict the structure response. The SOSFs can be classified into stationary and vibrating components. The vibrating component can deviate the time-series of response from the harmonic wave, and the stationary component directly determines the mean value of the time-series.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-29T08:00:00Z
      DOI: 10.1142/S0219455422500419
       
  • Analytical Solution for Vibrations of a Modified Timoshenko Beam on
           Visco-Pasternak Foundation Under Arbitrary Excitations

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      Authors: Haitao Yu, Xizhuo Chen, Pan Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      An analytical solution is derived for dynamic response of a modified Timoshenko beam with an infinite length resting on visco-Pasternak foundation subjected to arbitrary excitations. The modified Timoshenko beam model is employed to further consider the rotary inertia caused by the shear deformation of a beam, which is usually neglected by the traditional Timoshenko beam model. By using Fourier and Laplace transforms, the governing equations of motion are transformed from partial differential forms into algebraic forms in the Laplace domain. The analytical solution is then converted into the time domain by applying inverse transforms and convolution theorem. Some widely used loading cases, including moving line loads for nondestructive testing, travelling loads for seismic wave passage, and impulsive load for impact vibration, are also discussed in this paper. The proposed generic solutions are verified by comparing their degraded results to the known solutions in other literature. Several examples are performed to further investigate the differences of the beam responses obtained from the modified and the traditional Timoshenko beam models. Results show that the modified Timoshenko beam simulates the beam responses more accurately than the traditional model, especially under the dynamic loads with a high frequency. The analytical solutions proposed in this paper can be conveniently used for design and applied as an effective tool for practitioners.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-29T08:00:00Z
      DOI: 10.1142/S0219455422500456
       
  • Lateral Impact Response of Elliptical Hollow and Partially Concrete-Filled
           Cold-Formed Steel Columns Under Static Axial Compression Load

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      Authors: Nayyer Mohammadi Rana, Elham Ghandi, Shirin Esmaeili Niari
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In recent years, the use of partially concrete-filled steel tubular (PCFST) columns has been considered due to their cost-effectiveness and reduction of structural weight in bridge piers and building columns. One of the critical discussions about these columns is their impact resistance. In this article, the dynamic response of hollow and PCFST columns with elliptical cross-section under simultaneous loading of static axial compressive load and lateral impact load is presented using finite element modeling in ABAQUS software (FEA). To ensure the accuracy of the numerical modeling, the analysis results are compared with the results of previous works. The effects of different parameters such as impact velocity, the height of the impact location, the impact direction, the impact block mass, the size and shape of the impact block are investigated in this paper. The results of the numerical analysis showed that the partially filled specimens had better performance than the hollow specimens. The changes in impact direction and impact block mass parameters have a significant effect on the failure of the columns, especially when they are under high impact velocity. Changing the impact velocity significantly affects the impact resistance of specimens. However, the size and shape of the impact block did not have a significant effect on the displacement of the column against the impact loading.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-29T08:00:00Z
      DOI: 10.1142/S0219455422500481
       
  • Torsional Vibration of a Pile in Transversely Isotropic Saturated Soil
           Considering Its Construction Disturbance Effect

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      Authors: Wenjie Ma, Yao Shan, Binglong Wang, Shunhua Zhou
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The torsional dynamic response of a pile embedded in transversely isotropic saturated soil is investigated while allowing for the construction of disturbance effect. The dynamic governing equations of soil are established based on Biot’s poroelastic theory. By virtue of the continuous conditions of stress and displacement of adjacent disturbance circle and the boundary conditions of pile-soil coupling system, the circumferential displacement of soil and the shear stress on pile-soil contact surface are derived. Subsequently, a closed-form solution for the torsional dynamic response of a pile is derived in the frequency domain. By using inverse Fourier transform and the convolution theorem, a quasi-analytical solution for the velocity response of the pile head subjected to a semi-sine excitation torque is derived in the time domain. The proposed analytical solution is verified by comparing with the two existing solutions available in literature. Following the present solution, a parameter study is undertaken to portray the influence on the complex impedance, twist angle and torque of pile.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-24T08:00:00Z
      DOI: 10.1142/S0219455422500444
       
  • Stochastic Substructural Response Reconstruction and Reliability Analysis
           of High-Dimensional Systems

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      Authors: Y. T. Jia, S. S. Law, N. Yang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Existing stochastic dynamic response analysis requires the probability distributions of all variables in the system. Some of them are difficult or even impossible to obtain, and assumed probability density functions are often adopted which may lead to potential unrealistic estimation. This error may accumulate with the dimension of the structural system. This paper proposed a strategy to address this problem in the response analysis of a high-dimensional stochastic system. Partial measurement and finite element model of the target substructure of the system are required. The stochastic responses at several unmeasured locations are reconstructed from the measured responses. Only the variability of the substructure is considered. Other parameters outside the substructure are represented by their mean values contributing to the measured responses. The proposed strategy is illustrated with the analysis of a seven-storey plane frame structure using the probability density evolution method integrated with the response reconstruction technique. Measurement noise is noted to have a large influence on stochastic dynamic responses as different from that in a deterministic analysis. The proposed stochastic substructural response analysis strategy is found more computational efficient than traditional approach and with more realistic information of the structure from the measured responses.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-15T08:00:00Z
      DOI: 10.1142/S0219455422500407
       
  • Dynamic Analysis of a Rotating Double-Tapered FGM Beam with Various Shear
           Models Using a Constrained Variational Method

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      Authors: Zixuan Zhou, Xiuchang Huang, Hongxing Hua
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      A constrained variation modeling method for free vibration analysis of rotating double tapered functionally graded beams with different shear deformation beam theories is proposed in this paper. The material properties of the beam are supposed to continuously vary in the width direction with power-law exponent for different indexes. The mathematical formulation is developed based on the geometrically exact beam theory for each beam segment, the admissible functions denoting motion quantities are then expressed by a series of Chebyshev orthogonal polynomials. The governing equations are eventually derived using the constrained variational method to involve the continuity conditions of adjacent segments. Different shear deformation beam theories have been incorporated in the formulations, and the nonlinear effect of bending–stretching coupling vibration together with the Coriolis effect is taken into account. Comparison of dimensionless natural frequencies is performed with the existing literature to ensure the accuracy and reliability of the proposed method. Comparative discussions are performed on the vibration behaviors of the double tapered rotating functionally graded beam with first-order shear deformation beam theory and other higher-order shear deformation beam theories. The effect of material property graduation, power-law index, rotation speed, hub radius, slenderness ratio, and taper ratios is scrutinized via parametric studies, respectively.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-15T08:00:00Z
      DOI: 10.1142/S0219455422500420
       
  • 2D and 2.5D Numerical Simulations for Vortex-Induced Vibration (VIV) of a
           1.5:1 Rectangular Cylinder

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      Authors: Bowen Yan, Yangjin Yuan, Dalong Li, Ke Li, Qingshan Yang, Ding Lin, Giuseppe Piccardo
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      The semi-periodic vortex-shedding phenomenon caused by flow separation at the windward corners of a rectangular cylinder would result in significant vortex-induced vibrations (VIVs). Based on the aeroelastic experiment of a rectangular cylinder with side ratio of 1.5:1, 2-dimensional (2D) and 2.5-dimensional (2.5D) numerical simulations of the VIV of a rectangular cylinder were comprehensively validated. The mechanism of VIV of the rectangular cylinder was in detail discussed in terms of vortex-induced forces, aeroelastic response, work analysis, aerodynamic damping ratio and flow visualization. The outcomes showed that the numerical results of aeroelastic displacement in the cross-wind direction and the vortex-shedding procedure around the rectangular cylinder were in general consistence with the experimental results by 2.5D numerical simulation. In both simulations, the phase difference between the lift and displacement response increased with the reduced wind speed and the vortex-induced resonance (VIR) disappeared at the phase difference of approximately 180∘. The work done by lift force shows a close relationship with vibration amplitudes at different reduced wind speeds. In 2.5D simulations, the lift force of the rectangular cylinder under different wind speeds would be affected by the presence of small-scale vortices in the turbulence flow field. Similarly, the phase difference between lift force and displacement response was not a constant with the same upstream wind speed. Aerodynamic damping identified from the VIV was mainly dependent on the reduced wind speed and negative damping ratios were revealed at the lock-in regime, which also greatly influenced the probability density function (PDF) of wind-induced displacement.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-09T08:00:00Z
      DOI: 10.1142/S021945542250033X
       
  • Dynamic Instability of Functionally Graded Carbon Nanotubes-Reinforced
           Composite Joined Conical-Cylindrical Shell

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      Authors: B. Uspensky, K. Avramov, N. Sakhno, O. Nikonov
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, dynamic instability of functionally graded carbon nanotubes (CNTs)-reinforced composite joined conical-cylindrical shell in supersonic flow is analyzed numerically. The higher-order shear deformation theory is applied to describe the stress–strain state of thin-walled structure. The assumed-mode method is used to derive the finite degrees-of-freedom dynamical system, which describes the structure motions. The structure motions are expanded by using the eigenmodes, which are obtained by the Rayleigh–Ritz method. The trial functions, which satisfy the continuity conditions at the cylindrical-cone junction, are used to obtain the eigenmodes. The properties of free vibrations of thin-walled structure are analyzed numerically. The dynamic instability of the joined conical-cylindrical shell in supersonic flow is analyzed using the characteristic exponents. As follows from the numerical study, the dynamic instability is arisen due to the Hopf bifurcation. The dependences of the supersonic flow critical pressure on the Mach number and the type of CNTs distribution are analyzed numerically.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-09T08:00:00Z
      DOI: 10.1142/S0219455422500390
       
  • A Wind Tunnel Study on the Aerodynamic Characteristics of Ice-Accreted
           Twin Bundled Conductors

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      Authors: Zhiyu Wan, Dandan Zhang, Zhenbiao Li, Shi Mo, Yu Zhang
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Galloping of twin bundled overhead conductors accreted by ice is a frequent phenomenon during freezing weather, which may damage the operation of transmission lines. To analyze the galloping behavior of iced conductors, their aerodynamic characteristics must be studied. In this study, models with two different outlines were designed and tested to determine a more suitable ice-accreted conductor testing model. Subsequently, the influences of the conductor type, ice thickness, wind turbulence intensity, and wake effect of the windward conductor on the aerodynamic coefficients of the conductors with crescent-shape ice are investigated. The results show that the strand outline of overhead conductors must be considered to improve the accuracy of aerodynamic tests. With increasing ice thickness, the aerodynamic stability becomes rapidly deteriorated. Under the wind turbulence intensity of 4%, the aerodynamic stability gets the most enhancement. Moreover, different conductor types have little impact on the aerodynamic coefficients. The wake caused by the windward conductor is the leading cause for the twin bundled iced conductors to have weaker aerodynamic stability than a single conductor. The aerodynamic coefficients determined in this study are essential for predicting the galloping amplitudes of ice-accreted twin bundled overhead conductors under different weather conditions.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-06T08:00:00Z
      DOI: 10.1142/S0219455422500389
       
  • Stability and Modal Conversion Phenomenon of Pipe-in-Pipe Structures with
           Arbitrary Boundary Conditions by Means of Green’s Functions

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      Authors: Xueping Chang, Jinming Fan, Duzheng Han, Bo Chen, Yinghui Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      In this paper, a closed-form frequency equation of the pipe-in-pipe (PIP) structure with arbitrary boundaries is obtained. The frequency equation is derived from Green’s function of the transverse forced vibration of the PIP structure and takes into account the effects of internal two-phase flow and axial pressure. The reliability of the method in this paper is proved by comparison with the published literature. In the numerical discussion part, the PIP structures with clamped-clamped, clamped-free, and elastic boundary conditions are used as examples to discuss. The effects of equivalent stiffness coefficient, internal flow velocity, and gas volume fraction on the stability of PIP structure are studied. The results show that the stability of the PIP structure is better than that of the single-pipe structure, and the greater the equivalent stiffness coefficient of the elastic layer, the higher the critical flow velocity of the structure. In addition, a modal conversion phenomenon existing in the PIP structure is discovered. There are different forms of modal conversion for different boundary conditions, and the modal conversion makes the order of instability of the PIP structure different from that of a single-pipe. The conclusion of this paper has positive significance for the dynamic research of PIP structure.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-12-04T08:00:00Z
      DOI: 10.1142/S0219455422500341
       
  • An Experimental Study of a Single-Degree-of-Freedom Impact Oscillator

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      Authors: Shun Zhong, Jingyuan Tan, Zhicheng Cui, Tanghong Xu, Liqing Li
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      Purpose. Impacts appear in a wide range of mechanical systems. To study the dynamical behavior introduced by impact in practical way, a single-degree-of-freedom impact oscillator rig is designed. Originality. A simple piece-wise linear system with symmetrical flexible constraints is designed and manufactured to carry out a wide range of experimental dynamic analysis and ultimately to validate piece-wise models. The new design choice is based on the following criteria: accuracy in representing the mathematical model, manufacturing simplicity, flexibility in terms of parameter changes and cost effectiveness as well avoidance of the delay introduced by the structure. Meanwhile, the new design provides the possibility of the applications of the complex control algorithms. Design/methodology/approach. The design process is described in detail. The initial experimental results of the rig as well as numerical simulation results are given. In this rig, the mass driven force is generated by electromagnet, which can be adjusted and control easily. Also, most of the physical parameters can be varied in a certain range to enhance flexibility of the system allowing to observe subtle phenomena. Findings. Compared with the simulation results, the designed rig is proved to be validated. Then, the initial experimental results demonstrate potentials of this rig to study fundamental impact phenomena, which have been observed in various engineering systems. They also indicate that this rig can be a good platform for investigating nonlinear control methods.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-11-30T08:00:00Z
      DOI: 10.1142/S0219455422500353
       
  • Experimental and Numerical Investigation of the Polyurea-Coated
           Ultra-High-Performance Concrete (UHPC) Column under Lateral Impact Loading
           

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      Authors: Bin Gao, Jun Wu, Pengcheng Jia, Shutao Li, Qiushi Yan, Shilin Xu
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      It was found that polyurea coating could improve the integrity and the corresponding durability of the structural components. However, the strengthening effect of polyurea coatings for structures built with emerging ultra-high-performance concrete (UHPC) is still unknown due to the lack of studies. Therefore, this paper investigated the effect of the polyurea coating on the lateral impact resistance of UHPC columns through a combined numerical and experimental study. A total of five specimens were fabricated, including two UHPC columns and three UHPC columns with polyurea coating. To better characterize the structural response under dynamic loading, impact cases with different drop weight impact heights and axial force ratios were employed. The results showed that the UHPC column with polyurea coating exhibited superior lateral impact resistance compared to the UHPC column. The presence of the axial force increased the lateral impact stiffness and further reduced the deflection of the specimen. In contrast, the polyurea coating improved the specimen’s ductility and mitigated the peak impact force, thereby maintaining the specimen’s integrity without sudden shear failure. A three-dimensional finite element (FE) model of polyurea-coated UHPC columns under impact loading was then established and confirmed the experimental results. With the validated FE model, an intensive parametric study was conducted to investigate the effects of polyurea thickness, axial force ratio and impact energy on the lateral impact resistance of the UHPC column. The presence of the polyurea coating could significantly improve the lateral impact resistance of the specimen, thereby preventing the shear failure of the UHPC column, and thus, the effective thickness of the polyurea layer for the UHPC column was determined to be 2–6[math]mm. The outcome of this research demonstrates the great merits of polyurea coating in improving the ductility and integrity of the UHPC column under lateral impact loading.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-11-30T08:00:00Z
      DOI: 10.1142/S0219455422500377
       
  • Modeling and Dynamics of Magnetically Repulsive Negative Stiffness
           Permanent Magnetic Array for Precision Air/Magnetic Composite Vibration
           Isolation

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      Authors: Yamin Zhao, Junning Cui, Limin Zou, Zhongyi Cheng
      Abstract: International Journal of Structural Stability and Dynamics, Ahead of Print.
      To reduce the natural frequency of air isolators and realize low or ultra-low frequency air/magnetic composite vibration isolation with large payloads, a magnetically repulsive negative stiffness permanent magnetic array (MRNSPMA) is proposed. Specifically, we utilize cuboidal permanent magnets to form a spatial array that is mechanically repulsive in the horizontal direction and structurally parallel in the vertical direction. The superiority of MRNSPMA in achieving high amplitude negative stiffness is verified. Furthermore, the effects of structural parameters on vibration transmissibility under the base and force excitations are investigated with the introduction of MRNSPMA. The displacement transmissibility, the force transmissibility and the frequency corresponding to the peak transmissibility are significantly reduced, validating the promise of MRNSPMA for improving the isolation performance of cutting-edge scientific experimental systems and facilities.
      Citation: International Journal of Structural Stability and Dynamics
      PubDate: 2021-11-18T08:00:00Z
      DOI: 10.1142/S0219455422500316
       
 
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