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CIVIL ENGINEERING (208 journals)                  1 2 | Last

Showing 1 - 200 of 208 Journals sorted alphabetically
ACI Structural Journal     Full-text available via subscription   (Followers: 20)
Acta Polytechnica : Journal of Advanced Engineering     Open Access   (Followers: 3)
Acta Structilia : Journal for the Physical and Development Sciences     Open Access   (Followers: 3)
Advances in Civil Engineering     Open Access   (Followers: 41)
Advances in Structural Engineering     Full-text available via subscription   (Followers: 33)
Agregat     Open Access   (Followers: 1)
Ambiente Construído     Open Access   (Followers: 1)
American Journal of Civil Engineering and Architecture     Open Access   (Followers: 35)
Architectural Engineering     Open Access   (Followers: 5)
Architecture and Engineering     Open Access  
Architecture, Civil Engineering, Environment     Open Access  
Archives of Civil and Mechanical Engineering     Full-text available via subscription   (Followers: 3)
Archives of Civil Engineering     Open Access   (Followers: 12)
Archives of Hydro-Engineering and Environmental Mechanics     Open Access   (Followers: 2)
ATBU Journal of Environmental Technology     Open Access   (Followers: 4)
Australian Journal of Structural Engineering     Full-text available via subscription   (Followers: 7)
Baltic Journal of Road and Bridge Engineering     Open Access   (Followers: 1)
BER : Building and Construction : Full Survey     Full-text available via subscription   (Followers: 10)
BER : Building Contractors' Survey     Full-text available via subscription   (Followers: 2)
BER : Building Sub-Contractors' Survey     Full-text available via subscription   (Followers: 2)
BER : Survey of Business Conditions in Building and Construction : An Executive Summary     Full-text available via subscription   (Followers: 3)
Berkeley Planning Journal     Open Access   (Followers: 5)
Bioinspired Materials     Open Access   (Followers: 5)
Bridge Structures : Assessment, Design and Construction     Hybrid Journal   (Followers: 14)
Building & Management     Open Access   (Followers: 2)
Building and Environment     Hybrid Journal   (Followers: 15)
Building Women     Full-text available via subscription  
Built Environment Project and Asset Management     Hybrid Journal   (Followers: 15)
Bulletin of Pridniprovsk State Academy of Civil Engineering and Architecture     Open Access   (Followers: 6)
Canadian Journal of Civil Engineering     Hybrid Journal   (Followers: 13)
Case Studies in Engineering Failure Analysis     Open Access   (Followers: 6)
Case Studies in Nondestructive Testing and Evaluation     Open Access   (Followers: 11)
Case Studies in Structural Engineering     Open Access   (Followers: 9)
Cement and Concrete Composites     Hybrid Journal   (Followers: 20)
Challenge Journal of Concrete Research Letters     Open Access   (Followers: 3)
Challenge Journal of Structural Mechanics     Open Access   (Followers: 5)
Change Over Time     Full-text available via subscription   (Followers: 2)
Civil and Environmental Engineering     Open Access   (Followers: 8)
Civil and Environmental Engineering Reports     Open Access   (Followers: 8)
Civil and Environmental Research     Open Access   (Followers: 17)
Civil Engineering = Siviele Ingenieurswese     Full-text available via subscription   (Followers: 4)
Civil Engineering and Architecture     Open Access   (Followers: 23)
Civil Engineering and Environmental Systems     Hybrid Journal   (Followers: 3)
Civil Engineering and Technology     Open Access   (Followers: 12)
Civil Engineering Dimension     Open Access   (Followers: 11)
Civil Engineering Infrastructures Journal     Open Access   (Followers: 1)
Cohesion and Structure     Full-text available via subscription   (Followers: 2)
Composite Structures     Hybrid Journal   (Followers: 290)
Computer-aided Civil and Infrastructure Engineering     Hybrid Journal   (Followers: 11)
Computers & Structures     Hybrid Journal   (Followers: 37)
Concrete Research Letters     Open Access   (Followers: 7)
Construction Economics and Building     Open Access   (Followers: 4)
Construction Engineering     Open Access   (Followers: 11)
Construction Management and Economics     Hybrid Journal   (Followers: 21)
Constructive Approximation     Hybrid Journal  
Curved and Layered Structures     Open Access   (Followers: 3)
DFI Journal : The Journal of the Deep Foundations Institute     Hybrid Journal   (Followers: 1)
Earthquake Engineering and Structural Dynamics     Hybrid Journal   (Followers: 17)
Enfoque UTE     Open Access   (Followers: 4)
Engineering Project Organization Journal     Hybrid Journal   (Followers: 7)
Engineering Structures     Hybrid Journal   (Followers: 13)
Engineering Structures and Technologies     Open Access   (Followers: 2)
Engineering, Construction and Architectural Management     Hybrid Journal   (Followers: 10)
Environmental Geotechnics     Hybrid Journal   (Followers: 5)
European Journal of Environmental and Civil Engineering     Hybrid Journal   (Followers: 10)
Fatigue & Fracture of Engineering Materials and Structures     Hybrid Journal   (Followers: 19)
Frontiers in Built Environment     Open Access   (Followers: 1)
Frontiers of Structural and Civil Engineering     Hybrid Journal   (Followers: 6)
Geomaterials     Open Access   (Followers: 3)
Geosystem Engineering     Hybrid Journal   (Followers: 2)
Geotechnik     Hybrid Journal   (Followers: 4)
Géotechnique Letters     Hybrid Journal   (Followers: 8)
GISAP : Technical Sciences, Construction and Architecture     Open Access  
HBRC Journal     Open Access   (Followers: 2)
Hormigón y Acero     Full-text available via subscription  
HVAC&R Research     Hybrid Journal  
Indonesian Journal of Urban and Environmental Technology     Open Access  
Indoor and Built Environment     Hybrid Journal   (Followers: 3)
Infrastructure Asset Management     Hybrid Journal   (Followers: 3)
Infrastructures     Open Access  
Ingenio Magno     Open Access   (Followers: 1)
Insight - Non-Destructive Testing and Condition Monitoring     Full-text available via subscription   (Followers: 30)
International Journal for Service Learning in Engineering     Open Access  
International Journal of 3-D Information Modeling     Full-text available via subscription   (Followers: 3)
International Journal of Advanced Structural Engineering     Open Access   (Followers: 17)
International Journal of Civil, Mechanical and Energy Science     Open Access   (Followers: 2)
International Journal of Concrete Structures and Materials     Open Access   (Followers: 15)
International Journal of Condition Monitoring     Full-text available via subscription   (Followers: 2)
International Journal of Construction Engineering and Management     Open Access   (Followers: 10)
International Journal of Engineering and Geosciences     Open Access  
International Journal of Geo-Engineering     Open Access   (Followers: 3)
International Journal of Geosynthetics and Ground Engineering     Full-text available via subscription   (Followers: 4)
International Journal of Masonry Research and Innovation     Hybrid Journal   (Followers: 1)
International Journal of Pavement Research and Technology     Open Access   (Followers: 6)
International Journal of Protective Structures     Hybrid Journal   (Followers: 6)
International Journal of Steel Structures     Hybrid Journal   (Followers: 2)
International Journal of Structural Engineering     Hybrid Journal   (Followers: 9)
International Journal of Structural Integrity     Hybrid Journal   (Followers: 2)
International Journal of Structural Stability and Dynamics     Hybrid Journal   (Followers: 7)
International Journal of Sustainable Built Environment     Open Access   (Followers: 5)
International Journal of Sustainable Construction Engineering and Technology     Open Access   (Followers: 8)
International Journal on Pavement Engineering & Asphalt Technology     Open Access   (Followers: 7)
International Journal Sustainable Construction & Design     Open Access   (Followers: 2)
Journal of Applied Research in Water and Wastewater     Open Access   (Followers: 1)
Journal of Bridge Engineering     Full-text available via subscription   (Followers: 13)
Journal of Building Engineering     Hybrid Journal   (Followers: 2)
Journal of Building Materials and Structures     Open Access   (Followers: 2)
Journal of Building Performance Simulation     Hybrid Journal   (Followers: 6)
Journal of Civil Engineering     Open Access  
Journal of Civil Engineering and Construction Technology     Open Access   (Followers: 15)
Journal of Civil Engineering and Management     Open Access   (Followers: 7)
Journal of Civil Engineering and Science     Open Access   (Followers: 9)
Journal of Civil Engineering Research     Open Access   (Followers: 7)
Journal of Civil Engineering, Science and Technology     Open Access   (Followers: 1)
Journal of Civil Society     Hybrid Journal   (Followers: 5)
Journal of Civil Structural Health Monitoring     Hybrid Journal   (Followers: 4)
Journal of Composites     Open Access   (Followers: 78)
Journal of Composites for Construction     Full-text available via subscription   (Followers: 13)
Journal of Computing in Civil Engineering     Full-text available via subscription   (Followers: 23)
Journal of Construction Engineering     Open Access   (Followers: 9)
Journal of Construction Engineering and Management     Full-text available via subscription   (Followers: 17)
Journal of Constructional Steel Research     Hybrid Journal   (Followers: 6)
Journal of Earth Sciences and Geotechnical Engineering     Open Access   (Followers: 4)
Journal of Fluids and Structures     Hybrid Journal   (Followers: 6)
Journal of Frontiers in Construction Engineering     Open Access   (Followers: 2)
Journal of Green Building     Full-text available via subscription   (Followers: 10)
Journal of Highway and Transportation Research and Development (English Edition)     Full-text available via subscription   (Followers: 14)
Journal of Infrastructure Systems     Full-text available via subscription   (Followers: 19)
Journal of Legal Affairs and Dispute Resolution in Engineering and Construction     Full-text available via subscription   (Followers: 5)
Journal of Marine Science and Engineering     Open Access   (Followers: 1)
Journal of Materials and Engineering Structures     Open Access   (Followers: 5)
Journal of Materials in Civil Engineering     Full-text available via subscription   (Followers: 8)
Journal of Nondestructive Evaluation     Hybrid Journal   (Followers: 9)
Journal of Performance of Constructed Facilities     Full-text available via subscription   (Followers: 3)
Journal of Pipeline Systems Engineering and Practice     Full-text available via subscription   (Followers: 6)
Journal of Rehabilitation in Civil Engineering     Open Access   (Followers: 3)
Journal of Solid Waste Technology and Management     Full-text available via subscription   (Followers: 1)
Journal of Structural Engineering     Full-text available via subscription   (Followers: 35)
Journal of Structural Fire Engineering     Full-text available via subscription   (Followers: 6)
Journal of Structural Mechanics     Open Access   (Followers: 1)
Journal of Structures     Open Access   (Followers: 4)
Journal of Sustainable Architecture and Civil Engineering     Open Access   (Followers: 3)
Journal of Sustainable Design and Applied Research in Innovative Engineering of the Built Environment     Open Access   (Followers: 1)
Journal of the Civil Engineering Forum     Open Access  
Journal of the South African Institution of Civil Engineering     Open Access   (Followers: 2)
Journal of Water and Environmental Nanotechnology     Open Access  
Journal of Water and Wastewater / Ab va Fazilab     Open Access  
Jurnal Spektran     Open Access   (Followers: 1)
Jurnal Teknik Sipil     Open Access  
Jurnal Teknik Sipil dan Perencanaan     Open Access   (Followers: 1)
Konstruksia     Open Access  
KSCE Journal of Civil Engineering     Hybrid Journal   (Followers: 2)
Latin American Journal of Solids and Structures     Open Access   (Followers: 4)
Materiales de Construcción     Open Access   (Followers: 1)
Mathematical Modelling in Civil Engineering     Open Access   (Followers: 4)
Media Komunikasi Teknik Sipil     Open Access  
Mokslas – Lietuvos ateitis / Science – Future of Lithuania     Open Access  
Nondestructive Testing And Evaluation     Hybrid Journal   (Followers: 15)
npj Materials Degradation     Open Access  
Obras y Proyectos     Open Access   (Followers: 1)
Open Journal of Civil Engineering     Open Access   (Followers: 9)
Periodica Polytechnica Civil Engineering     Open Access  
Photonics and Nanostructures - Fundamentals and Applications     Hybrid Journal   (Followers: 4)
Practice Periodical on Structural Design and Construction     Full-text available via subscription   (Followers: 3)
Proceedings of the Institution of Civil Engineers - Bridge Engineering     Hybrid Journal   (Followers: 8)
Proceedings of the Institution of Civil Engineers - Civil Engineering     Hybrid Journal   (Followers: 14)
Proceedings of the Institution of Civil Engineers - Management, Procurement and Law     Hybrid Journal   (Followers: 10)
Proceedings of the Institution of Civil Engineers - Municipal Engineer     Hybrid Journal   (Followers: 2)
Proceedings of the Institution of Civil Engineers - Structures and Buildings     Hybrid Journal   (Followers: 3)
Promet : Traffic &Transportation     Open Access  
Random Structures and Algorithms     Hybrid Journal   (Followers: 5)
Recent Trends In Civil Engineering & Technology     Full-text available via subscription   (Followers: 5)
Research in Nondestructive Evaluation     Hybrid Journal   (Followers: 6)
Resilience     Open Access   (Followers: 1)
Revista IBRACON de Estruturas e Materiais     Open Access   (Followers: 1)
Revista Sul-Americana de Engenharia Estrutural     Open Access  
Road Materials and Pavement Design     Hybrid Journal   (Followers: 11)
Russian Journal of Nondestructive Testing     Hybrid Journal   (Followers: 5)
Science and Engineering of Composite Materials     Hybrid Journal   (Followers: 61)
Selected Scientific Papers - Journal of Civil Engineering     Open Access   (Followers: 3)
Slovak Journal of Civil Engineering     Open Access   (Followers: 2)
Soils and foundations     Full-text available via subscription   (Followers: 5)
Steel Construction - Design and Research     Hybrid Journal   (Followers: 3)
Structural and Multidisciplinary Optimization     Hybrid Journal   (Followers: 11)
Structural Concrete     Hybrid Journal   (Followers: 11)
Structural Control and Health Monitoring     Hybrid Journal   (Followers: 8)
Structural Engineering International     Full-text available via subscription   (Followers: 11)
Structural Mechanics of Engineering Constructions and Buildings     Open Access   (Followers: 1)
Structural Safety     Hybrid Journal   (Followers: 6)
Structural Survey     Hybrid Journal  
Structure     Full-text available via subscription   (Followers: 24)
Structure and Infrastructure Engineering: Maintenance, Management, Life-Cycle Design and Performance     Hybrid Journal   (Followers: 12)
Structures     Hybrid Journal   (Followers: 1)
Study of Civil Engineering and Architecture     Open Access   (Followers: 10)
Superlattices and Microstructures     Hybrid Journal   (Followers: 2)
Surface Innovations     Hybrid Journal  
Technical Report Civil and Architectural Engineering     Open Access   (Followers: 1)
Teknik     Open Access  
Territorium : Revista Portuguesa de riscos, prevenção e segurança     Open Access  
The IES Journal Part A: Civil & Structural Engineering     Hybrid Journal   (Followers: 6)

        1 2 | Last

Journal Cover
Journal of Rehabilitation in Civil Engineering
Number of Followers: 3  

  This is an Open Access Journal Open Access journal
ISSN (Print) 2345-4415 - ISSN (Online) 2345-4423
Published by Semnan University Homepage  [2 journals]

    • Abstract: This paper introduces a novel design concept for the development of efficient, sustainable Rocking-Wall Moment Frames (RWMFs) under seismic conditions. The proposed concepts lead to a novel structural configuration with provisions for Collapse Prevention (CP), Self-Centering (SC), reparability, performance control (PC), damage reduction, and energy based seismic analysis. It introduces the merits of design led analysis (DLA) over the traditional methods of approach, followed by the development of a lateral resisting system that is more efficient than its conventional counterparts. The fundamental idea behind the proposed methodology is that seismic structural response is mainly a function of design and construction, rather than numerical analysis. In design led analysis the rules of mechanics and structural design are induced rather than followed .The new system is a combination of grade beam restrained moment frames and articulated shear walls, tied to each other by means of post tensioned (PT) stabilizers and Gap Opening Link Beams (GOLBs).
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Effect of Pile Scouring on the Structural Behavior of a Fixed Jacket
           Platform with ...

    • Abstract: In offshore structures, most of failures are caused by the lack of sufficient piles strength. Scour phenomena affects the load transition and the pile strength. The necessity of the consideration of scouring phenomena amplifies when the scour depth becomes remarkable, which can endanger the jacket stability. In this paper, a new method is used to consider the pile scouring using nonlinear pushover analysis with SACS software. A recently-built existing jacket platform namely SPD 19C is selected as a case study. Results show that Reserve Strength Ratio (RSR) of the jacket platform decreases when scour depth increased in the both aged and recently-built cases. RSR decreasing becomes more sensible as scour depth increases. According to API RP2A collapse will be occurred in the range of RSR< 1.6. It is shown at RSR=1.6, collapse will be occurred in the scouring depth of 13.5m and 11m for recently-built and aged platform respectively, which both have approximately 27% lower RSR than their original state. So scour protection methods should be addressed in vulnerable areas as preventive alternatives.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Modeling of resilient modulus of asphalt concrete containing reclaimed
           asphalt pavement using ...

    • Abstract: Reclaimed asphalt pavement (RAP) is one of the waste materials that highway agencies promote to use in new construction or rehabilitation of highways pavement. Since the use of RAP can affect the resilient modulus and other structural properties of flexible pavement layers, this paper aims to employ two different artificial neural network (ANN) models for modeling and evaluating the effects of different percentages of RAP on resilient modulus of hot-mix asphalt (HMA). To this end, 216 resilient modulus tests were conducted for establishing the experimental dataset. Input variables for predicting resilient modulus were temperature, penetration grade of asphalt binder, loading frequency, change of asphalt binder content compared to optimum asphalt binder content and percentage of RAP. Results of modeling using feed-forward neural network (FFNN) and generalized regression neural network (GRNN) model were compared with the measured resilient modulus using two statistical indicators. Results showed that for FFNN model, the coefficient of determination between observed and predicted values of resilient modulus for training and testing sets were 0.993 and 0.981, respectively. These two values were 0.999 and 0.967 in case of GRNN. So, according to comparison of R2 for testing set, the accuracy of FFNN method was superior to GRNN method. Tests results and artificial neural network analysis showed that the temperature was the most effective parameter on the resilient modulus of HMA containing RAP materials. In addition by increasing RAP content, the resilient modulus of HMA increased.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010

    • Abstract: Buckling restrained braced frames (BRBFs) for seismic load resistance have been widely used in recent years. One of the key requirements for a buckling restrained brace is to sustain large plastic deformations under severe ground motions. The core of a buckling restrained brace is prone to fatigue fracture under cyclic loading. The earthquake induced fracture type of the core plate in a buckling restrained brace can be categorized as ultra-low cycle fatigue fracture. This paper investigates the ultra-low cycle fatigue fracture life of a type of composite buckling restrained brace previously tested. The newly developed cyclic void growth model was adopted to theoretically predict the fracture and crack initiation in the core. In addition, the Coffin-Manson fatigue damage model was applied to estimate the fracture life of the brace. A FEM model of the BRB developed in ABAQUS was used to evaluate the fatigue life. The analysis results showed that the cyclic void growth model is capable to nearly predict the fracture life of the core in buckling restrained brace.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Prediction of ligthweight aggregate concrete compressive strength

    • Abstract: Nowadays, the better performance of lightweight structures during earthquake has resulted in using lightweight concrete more than ever. However, determining the compressive strength of concrete used in these structures during their service through a none-destructive test is a popular and useful method. One of the main methods of non-destructive testing in the assessment of compressive strength of concrete in the service is ultrasonic pulse velocity test. The aim of this study is predicting the compressive strength of lightweight aggregate concrete by offering a suitable mathematical formulation. Many samples of lightweight aggregate concrete, made by expanded clay, have been produced and tested. After determining the actual compressive strength and indirect ultrasonic pulse velocity for each sample, a relationship was presented to predict the compressive strength through Gene Expression Programming (GEP). The results show the presented equation has high accuracy in estimating the compressive strength of samples and that experimental results are perfectly compatible with the test results.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Nonlinear Finite Element Modeling of Different Cross-Sectional Shapes of
           Slender RC Columns ...

    • Abstract: In the present study, non-linear finite element analyses are carried out on the slender reinforced concrete columns wrapped using CFRP composite with different cross-sectional shapes having the same area. Thickness of the CFRP wraps, concrete compressive strength, corner radius, loading condition, slenderness ratio and column size are the main parameters of this study. According to this, four different eccentricity-to-section-height ratios, four different levels of the CFRP thicknesses in the strengthened specimens, the slenderness ratio of the length to the section-height (l/h) from 6 to 12, three various types of column size, concrete compressive strength values from 20 MPa to 50 MPa and corner radius from 10 to 40 mm are considered. This paper presents a comparison of a numerical simulation using ABAQUS software, with the results of experimental tests by previous researchers to validate finite element models. It is shown that the predicted results by this numerical study are in reasonable agreement with the results of experimental studies. The results of this investigation also represented a considerable enhancement on the performance of strengthened columns with CFRP compared to unstrengthened columns.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010

    • Abstract: This paper aims to study the influence of soil-structure interaction on plastic energy demand spectra directly derived from the energy-balance equations of soil-shallow-foundation structure with respect to an ensemble of far-field strong ground motions obtained from Pacific Earthquake Engineering Research (PEER) database and recorded on alluvium soil. The superstructure is modeled as a single-degree-of-freedom (SDOF) oscillator with Modified Clough stiffness degrading model resting on flexible soil. The soil beneath the superstructure is considered as a homogeneous elastic half space and is modeled through the concept of Cone shallow foundation Models. A parametric study is carried out for 2400 soil-structure systems with various aspect ratios of the building as well as non-dimensional frequency as a representative of the structure-to-soil stiffness ratio having a wide range of fundamental fixed-base period and target ductility demand values under a family of 19 earthquake ground motions. Results show that generally for the structure located on softer soils severe dissipated energy drop will be observed with respect to the corresponding fixed-base system. The only exception is for the case of short period slender buildings in which the hysteretic energy demand of soil-structure systems could be up to 70% larger than that of their fixed-base counterparts. Moreover, dissipated energy spectra are much more sensitive to the variation of target ductility especially for the case of drastic SSI effect.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Determining the Effective Distance of Wind Shelter Index by Defining
           Innovative Index Named ...

    • Abstract: The wind’s effectiveness was compared in different points of a watershed using a quantity called The Wind Shelter Index.The wind’s effectiveness was compared in different points of a watershed using a quantity called The Wind Shelter Index. It is necessary to choose a distance called the effective distance in the process of this index determination. The criterion already used for this purpose was only usable in snowy places. According to the wind shelter index usability in some phenomena that are not in snowy areas, the use of this index will be applied. This study uses observational data of snow surveys from 258 points in Samsami Basin to introduce a new index called “Virtual Wind Shelter” that can be used to choose the effective distance of the area applicable in snowy and non-snowy places. The results showed that the index introduced in this study has the capability of replacement with the correlation of wind shelter index with snow depth criterion.
      PubDate: Tue, 31 Jul 2018 19:30:00 +010
  • Fatigue Evaluation in Hot and Warm mix asphalts Based on Dissipated Energy

    • Abstract: Warm mix asphalts (WMA), because of their low production and compact temperatures, may have different behaviors in long term. In the present work, the energy-based criteria along with the 50% reduction in initial stiffness (Nf50%) using four-point bending test under controlled-strain conditions of 1000 microstrain were applied to compare the prepared two warm mix and HMA samples. All these criteria illustrate properly the effect of mix asphalt properties (additive type) on its fatigue performance. A noteworthy point in this regard is the difference between Nf50% values of the studied samples with the real failure point. For HMA and zycotherm WMA (ZWMA), loading cyclic number at the failure moment occurs almost 80% higher than the fatigue life estimated using Nf50% while for Sasobit WMA (SWMA) this value is declined to 28%. The RDEC method, compared to other methods, indicated the maximum fatigue life and consistency with the failure point. Comparing the energy-based methods with Nf50% method revealed that ERR, ERR&B, and ERP have the maximum consistency with fatigue life in terms of 50% reduction in initial stiffness. For SWMA, the fatigue life at Nf50% was larger than that of various energy-based methods but almost equal to that of the RDEC method. However, for two WMA mixes prepared using ZWMA and HMA, all energy methods revealed a fatigue life longer than that of Nf50%.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Experimental study of Hydraulic Flow of Circular Piano-Key Inlet in Shaft

    • Abstract: One of the most important conflicts that shaft spillways have to deal with is vortex formation. This phenomenon leads to some unfavorable effects such as vibration in the body of structures, air entrainment and reduced overflow capacity of the spillway. Among all solutions for disrupted vortex formation, an innovative one called circular piano-key spillway, based upon piano key weir principles has not been noticed as well as other solutions. Hence, in this study, experiments were conducted on circular piano-key spillway models. Results showed that in a constant head, the greater amounts of discharge have been measured for circular piano key inlet with an angle of 90 degrees. Comparison between discharge coefficients of three circular piano key inlet models showed that for a constant amount of H/D (Head/Diameter), circular piano key inlet with an angle of 90, 60 and 45 degrees have the greater amount of discharge coefficients, respectively. Experiment results indicated that circular piano-key spillway (with an angle of 90 degrees) increases overflow discharge capacity about 15.16% compared with shaft spillway. Among circular piano key inlets, the model with an angle of 90 degrees has the best hydraulic performance.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • A Target Displacement for Static Pushover Analysis to Estimate Seismic
           Demand of Eccentrically ...

    • Abstract: A main challenge for performance-based seismic engineering is to develop simple, practical and precise methods for analyzing designed buildings and assessing existing structures to satisfy considerable performance objectives. Pushover analysis is a simplified nonlinear analysis technique that can be implemented for estimating the dynamic demands imposed on a structure under earthquake excitations. In this method, structure is subjected to specified load pattern to reach a target displacement. The present study provides a target displacement for estimating the seismic demand of eccentrically braced frame system (EBFs). A parametric study is conducted on a group of 30 EBFs under a set of 15 far-field and near-field accelerograms. The results of nonlinear dynamic analyses of EBFs have been post-processed by nonlinear regression analysis and a relation is proposed for target displacement. In order to verify the capability of the proposed procedure, three EBFs are assessed by the present method in which the results show that the proposed method is capable of reproducing the peak dynamic responses with relatively good accuracy. Additionally, the comparison of obtained results with those of other conventional target displacement methods such as N2 method, and displacement coefficient method confirms the efficiency of the suggested one.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Experimental Investigation of Corrosion Cracking in Reinforced Concrete
           Beams Containing Nano ...

    • Abstract: Cracking of the concrete cover due to corrosion is defined as the serviceability limit state of reinforced concrete structures. This study evaluated the influence of a mineral admixture i.e. nano wollastonite on corrosion performance and serviceability of reinforced concrete structures by performing an accelerated corrosion test on ten reinforced concrete beams under a sustained load. To do so, five concrete beams were treated with nano wollastonite (NCW), while the others were normal concrete beams (NC). The results were discussed in terms of corrosion crack patterns, crack width, half-cell potentials, rebar mass loss, and rebar diameter degradation at different corrosion levels. The results showed that the incorporation of nano wollastonite in reinforced concrete beams increased the service life by increasing the initial cracking time, decreasing the corrosion crack growth rate and rebar mass loss. Given the maximum 0.3 mm corrosion crack width as limit state criteria, the lifetime of the NCW reinforced beams was 3.6 times longer than that of Group NC. The experimental results were compared with existing models. However, these models were unreliable in predicting the steel cross-section loss based on crack width. To solve this problem, a GMDH-type neural network model was developed and evaluated using obtained experimental data for NC and NCW beams.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Analytical assessment of reinforced concrete frames equipped with TADAS

    • Abstract: In recent years, it is considerably attempted to develop the concept of energy dissipation as an applicable technology to overcome the energy released by earthquakes. The passive control systems such as metallic dampers have been widely considered. The dampers are basically used to mitigate the structural responses and reduce the damages in main structural elements by energy dissipation. The present paper is aimed to evaluate the seismic behavior of three conventional concrete moment resisting frames having 4, 7 and 10 stories incorporating seismic strength imperfection equipped with Triangular Added Damping and Stiffness (TADAS) metallic dampers. OpenSees and nonlinear time-history analysis incorporating seven seismic records have been used to define the frame response. The results revealed that the seismic response of retrofitted frames has been considerably improved. Where, the drift of the stories have been constant and the maximum values in retrofitted 4, 7 and 10 story frames have been decreased 54%, 56% and 55%, respectively. Also, the maximum roof displacement, the maximum floor acceleration, the maximum story shears have been declined in damper equipped frames and the seismic performance of the most retrofitted frame elements has been upgraded to Immediate Occupancy (IO) and Live Saftey (LS) performance level.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Experimental Strengthening of the Two-way Reinforced Concrete Slabs with
           High Performance Fiber ...

    • Abstract: Reinforced concrete structures need to be strengthened and retrofitted for various reasons, including errors during design and/or construction, so in most cases strengthening of structural elements is much more economical than rebuilding the structure. Using HPFRCC with tensile stiffening behavior has been developed to strengthen the concrete structures over the recent few years. In this paper, the usage of HPFRCC for strengthening two-way reinforced concrete slabs has been studied. A total of five two-way slabs were constructed and tested to reach their own collapse stage, one of specimen was as non-strengthened control slab, and the others were strengthened in various forms. The strengthening was carried out in two ways; by installing precast plate in the tensile area and the other by installing precast plate in both tensile and compression area at two different percentages of the fiber. The bending behavior, cracking, yielding and rupture of the experimental specimens were evaluated. The results indicated that the installation of HPFRCC pre-fabricated laminates significantly improved the bending performance of reinforced slabs, so that the ductility, energy absorption value, cracking strength, and initial hardness of the slabs was increased and the crack width was decreased. Therefore, the proposed precast HPFRCC sheets can be used to strengthening the deficient slabs.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Evaluating the application of reinforcement correction factor for concrete
           core testing

    • Abstract: This study investigates the reinforcement correction factor of concrete core in more detail to prepare appropriate outlines for interpretation of results in order to minimize uncertainties involved to carry out the more realistic condition assessment of suspect buildings before taking up retrofitting/strengthening measures. For this purpose, an extensive experimental program including different concrete strength level, moisture condition, core size, length-to-diameter (L/D) ratio of core and steel bar size with various configurations was under taken. The effect of variation of foregoing parameters on the ratio of average compressive strength of cores containing steel bars to that of corresponding plain specimens was probed. The results show that the correction factors are highly dependent on the values of volume percentage and position of reinforcing bars in the core, which are extremely interrelated. Hence, the experimental results do not show a good agreement with the provisions by the British Standard 6089 and Concrete Society Report No.11. Therefore, a statistical analysis on the prediction of cube compressive strength using linear and nonlinear regression models is accomplished. The results showed that regression models have great ability as a feasible tool for prediction of compressive strength on the basis of core testing in the presence of steel bars. However, the most accurate results obtained by nonlinear equations in comparison with linear models.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Estimation of the elastic properties of important calcium silicate
           hydrates in nano scale - a ...

    • Abstract: Approximately, 50 to 70 percent of hydration products in hydrated cement paste are polymorphisms of C-S-H gel. It is highly influential in the final properties of hardened cement paste. Distinguishing C-S-H nano-structure significantly leads to determine its macro scale ensemble properties. This paper is dealt with nano-scale modeling. To achieve this, the most important C-S-H compounds, with a vast range ratios of Ca/Si from 0.5 to 3 were chosen and used in different simulations. These materials included tobermorite 9Å, tobermorite 11Å, tobermorite 14Å, clinotobermorite, jennite, afwillite, okenite, jaffeite, foshagite, and wollastonite. Furthermore, the molecular dynamics method was used to estimate important mechanical properties such as bulk modulus, shear modulus, Young's modulus and poisson ratio. Five different force fields (COMPASS, COMPASS II, ClayFF, INTERFACE and Universal) were used and compared with each other to be able to measure the mechanical properties of these compounds. Lastly, the properties of two types of C-S-H with high and low density were determined by using Mori-Tanaka method. The main aim of this paper is to distinguish the most similar natural C-S-H material to C-S-H from cement hydration and finding appropriate force filed.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Stochastic analysis of two adjacent structures subjected to structural
           pounding under ...

    • Abstract: Seismic pounding occurs as a result of lateral vibration and insufficient separation distance between two adjacent structures during earthquake excitation. This research aims to evaluate the stochastic behavior of adjacent structures with equal heights under earthquake-induced pounding. For this purpose, many stochastic analyses through comprehensive numerical simulations are carried out. About 4.65 million time-history analyses were carried out over the considered models within OpenSees software framework. Various separation distances effects are also studied. The response of considered structures is obtained by means of Hertzdamp contact element. The models have been excited using 25 earthquake records with different peak ground accelerations. The probability of collision between neighboring structures has been evaluated. An efficient combination of analytical and simulation techniques is used for the calculation of the separation distance under the assumptions of non-linear elasto-plastic behavior for the structures. The results obtained through Monte Carlo simulations show that use of the current provision’s rule may significantly overestimate or underestimate the required separation distance, depending on the natural vibration periods of adjacent buildings. Moreover, based on the results, a formula is developed for stochastic assessment of required separation distance.
      PubDate: Thu, 19 Jul 2018 19:30:00 +010
  • Forest road design combining common design techniques and GIS (Case Study:
           2nd series of ...

    • Abstract: Nowadays, it is necessary to apply modern techniques for the design of road networks, especially roads passing through ecosystems such as forests, in order to reduce operating costs, prevent further degradation of the environment, increase road efficiency and achieve sustainable development goals. In this paper, a new way of designing the road is presented. New design method has the ability to analyze a large amount of information in a variety of digital layers using GIS while being able to store, recover, and analyze information through multi-criteria decision-making process (AHP) and routing algorithms at high speed and precision. The output of the proposed design method (combining information with AHP via Dijkstra algorithm in GIS software) is compared with the existing forest road in the 2nd series of Liresar in Mazandaran province of Iran, designed using common methods. According to experts, hydrological criteria (0.408) and environmental criteria (0.375) have the highest importance and weight in comparison with other criteria in forest road design. The results show the map of area's capability for road construction is prepared for road design with better functionality and less adverse effects on the environment using the divider method compared to conventional topographic maps. Finally, the design of the new road in comparison with the existing reduce the slope (5%), increase access (15%) and reduce the cost of construction (30%).
      PubDate: Sat, 14 Jul 2018 19:30:00 +010
  • Study of effect of paste volume, water to cementitious materials and fiber
           dosages on ...

    • Abstract: As a vibration- free concrete, self- compacting concrete (SCC) can be easily used in the absence of consolidation, therefore; it is a good option for repairing and retrofitting concrete structures. The quality of repair layer is highly effective on a successful repair. Accordingly, in this study, factors affecting the quality of fiber-reinforced self-compacting concrete repair layer, including paste volume, the ratio of water to cementitious materials and the amount of fiber, are discussed. For this purpose, the in-situ strength of repair layers and core and non-core sample cubes are determined using pull- off method. Also comparisons between in-situ strengths in different methods (with and without core, on cubes or on repair layer) with compressive and tensile strength of specimens is done. Results show that, considering the great influence of shrinkage and tensile strength, with reduced paste volume, cementitious material and increased fiber, the in-situ strength of repair layer increases. Moreover, we found that even in the best condition of concrete substrate layer (i.e. saturated surface dry) a repair layer has a lower strength than a cube specimen. Also, presence of fibers has the huge effect on results of pull-off test depends on the method of the test (with or without core).
      PubDate: Tue, 12 Jun 2018 19:30:00 +010
  • Damage identification of structures using second-order approximation of
           Neumann series expansion

    • Abstract: In this paper, a novel approach proposed for structural damage detection from limited number of sensors using extreme learning machine (ELM). As the number of sensors used to measure modal data is normally limited and usually are less than the number of DOFs in the finite element model, the model reduction approach should be used to match with incomplete measured mode shapes. The second-order approximation of Neumann series expansion based model reduction approach has been used to condense mass and stiffness matrices. Frequencies and mode shapes of damaged structures and corresponding generated damage states used as input and output to train extreme learning machine, respectively. To evaluate the performance of proposed approach, three examples consists of a truss structure, irregular frame and shear frame have been studied. Results show the ability of the proposed approach in detecting and estimating different damage scenarios using limited numbers of installed sensors and noisy modal data.
      PubDate: Mon, 11 Jun 2018 19:30:00 +010
  • Second-Order Statistical Texture Representation of Asphalt Pavement
           Distress Images Based on ...

    • Abstract: Assessment of pavement distresses is one of the important parts of pavement management systems to adopt the most effective road maintenance strategy. In the last decade, extensive studies have been done to develop automated systems for pavement distress processing based on machine vision techniques. One of the most important structural components of computer vision is the feature extraction method. In most of the application areas of image processing, textural features provide more efficient information of image regions properties than other characteristics. In this research, three different algorithms were used to extract the feature vector and statistically analyzing the texture of six various types of asphalt pavement surface distresses. The first algorithm is based on the extraction of images second-order textural statistics utilizing gray level co-occurrence matrix in spatial domain. In second and third algorithms, the second-order descriptors of images local binary patterns were extracted in spatial and wavelet transform domain, respectively. The classification of the disress images based on a combination of K-nearest neighbor method and Mahalanobis distance, indicates that two stages arranging of the gray levels of the distress images edges by applying wavelet transform and local binary pattern (third algorithm) had a superior result in comparison with other algorithms in texture recognition and separation of pavement distresses. Classification performance accuracy of the distress images based on first, second and third feature extraction algorithms is 61%, 75% and 97%, respectively.
      PubDate: Mon, 11 Jun 2018 19:30:00 +010
  • Stepwise Regression for shear capacity assessment of steel fiber
           reinforced concrete beams

    • Abstract: The addition of steel fibers into concrete improves the postcracking tensile strength of hardened concrete and hence significantly enhances the shear strength of reinforced concrete reinforced concrete beams. However, developing an accurate model for predicting the shear strength of steel fiber reinforced concrete (SFRC) beams is a challenging task as there are several parameters such as the concrete compressive strength, shear span to depth ratio, reinforcement ratio and fiber content that affect the ultimate shear resistance of fiber reinforced concrete (FRC) beams. This paper investigates the feasibility of stepwise regression (SR) to create an empirical model for the ultimate shear strength of SFRC beams without stirrups. The model produced by SR is constructed directly from a set of experimental results available in the literature. The results of training and testing sets of the model are compared with experimental results. All of the results show that SR model is fairly promising approach for the prediction of shear strength of SFRC beams. The performance of the SR model is also compared with different proposed formulas available in the literature. It was found that the SR model provides the most accurate results in calculating the shear strength of SFRC beams among existing shear strength formulas.
      PubDate: Sun, 10 Jun 2018 19:30:00 +010
  • Estimating the inter-story drift in high rise buildings with the flexural
           and shear cantilever ...

    • Abstract: In this study, the seismic inter-story drift of structures is estimated by a combination of mode-acceleration equations with the modelling of high-rise buildings with flexural and shear cantilever beams. In the equation presented for calculating the inter-story drift, having less knowledge of the building is adequate and this issue is of significance in estimating the nonstructural component forces, especially in high-rise buildings and also in the initial design of structures. Also, a comparison of inter-story drift estimated by the approximation method with an exact method indicates that the application of the mode-acceleration method compared to mode-displacement with a fewer number of modes comes close to the exact calculation, which facilitates and expedites the analysis. In order to carry out an exact evaluation of the presented equation, inter-story drift is calculated and compared in 10, 15 and 50 story buildings during three seismic records using approximate relations. Exact analysis of those structures is done in finite element Opensees software. The results of comparisons show that the presented equation provides an adequate estimation without the need for modelling and lengthy software analysis.
      PubDate: Sun, 10 Jun 2018 19:30:00 +010
  • Effect of Steel Confinement on Behavior of Reinforced Concrete Frame

    • Abstract: The strength and ductility of concrete improve under multi-axial compressive stress due to confinement effect. Some parameters are effective for considering the confinement in concrete and various stress-strain models were developed by different researchers. Longitudinal and transverse reinforcement steels can influence on confinement in reinforced concrete members. In this paper, various stress strain models with considering the steel confinement effect are reviewed briefly and applied on an experimental reinforced concrete frame. Envelope curves, cracking and yielding patterns, ductility and energy absorption of the frames are discussed. Results from the finite element analysis compared with experimental findings show that in the case of lateral load and displacement, the analytical models which were presented by Fafitis et al. and Muguruma et al. had more compatibility with experimental results and the difference is less than 10%. Energy absorption of the model of Khaje Samani & Attard had the most compatibility with experimental results and difference is about 1%.
      PubDate: Sun, 10 Jun 2018 19:30:00 +010
  • Seismic Behavior Effect of Knee Braced Frames Considering Different Type
           of Geometry under ...

    • Abstract: The design and behavior of a ductile structural system called a knee-braced moment frame are presented in this paper. The design of this structural system is based on a capacity-design concept that results in ductile behavior. The knee part is a fuse-like component that dissipates energy by the formation of plastic flexural and/or shear hinges at its ends and mid-span, when the building is subjected to severe lateral loads. However, the diagonal brace component, on the other hand, provides the required level of lateral stiffness and remains in the elastic range without buckling at any time. Attempts have been made, in the present study, to investigate the non-linear seismic behavior of Knee-Braced Frame systems for various influencing factors, and to formulate the effects of the number of building stories, the length of the knee element, and moment of inertia of the bending members on the seismic behavior, the drift of the stories, and the failure mode of these systems. Finally, based on the results of the study, some recommendations have been offered for the effective range parameters for the optimal performance of these systems.
      PubDate: Sun, 10 Jun 2018 19:30:00 +010
  • Evaluating Seepage of Dam Body Using RBF and GFF Models of Artificial
           Neural Network

    • Abstract: Dams have been always considered as the important infrastructures and their critical values are counted. Hence, evaluation and avoidance of dams’ destruction have a specific importance. Seepage occurrence in dams is an inevitable phenomenon. Despite all the progress in geotechnical engineering, up to now, seepage problem is the main conflict which occurs in dams. This study tried to estimate seepage of the embankment of "Boukan Shahid Kazemi’s dam” using RBF and GFF models of artificial neural network. To achieve this goal, the piezometric data set including 864 data were used. 70 percent of current data was used for training the network and 10 percent for calibration of two models. So 20% remained data was used for testing the network. Using suitable and applicable statistical parameters indicated that the RBF model with Levenberg Marquardt training and 4 hidden layers has high potential in estimating seepage, also the correlation coefficient for this model is 0.81 and the root mean square error was obtained 33.12%.
      PubDate: Sun, 10 Jun 2018 19:30:00 +010
  • Forecasting of Shear Strength of Concrete Beam Reinforced with FRP Bar

    • Abstract: This study develops a new approach for forecasting shear Strength of concrete beam without stirrups based on the artificial neural networks (ANN). Proposed ANN considers geometric and mechanical properties of cross section and FRP bars, and shear span-depth ratio. The ANN model is constructed from a set of experimental database available in the past literature. Efficiency of the ANN model was compared with existing approaches in the literature using comprehensive database. ANN is powerful tools in solving complex problems of civil engineering. The Levenberg–Marquardt (LM) method was applied for training algorithm. These existing approach include the American Concrete Institute design guide (ACI 440.1R-06), ISIS Canadian design manual (ISIS-M03-07), the British Institution of Structural Engineers guidelines (BISE), JSCE Design Recommendation, CNR-DT 203-06 Task Group, and Kara. The results demonstrate that ANN method has good agreement in calculating the shear strength of concrete beam reinforced with FRP bar among existing equations in recent decades.
      PubDate: Sat, 19 May 2018 19:30:00 +010
  • Energy life cycle analysis of a residential building with the help of BIM
           in different climates ...

    • Abstract: With energy resource scarcity and energy crisis in the world, energy efficiency has become a subject of great importance. In warm and humid climates as well as cold and mountainous ones, annual energy consumption is too high to achieve desirable living conditions in built environments, and hence energy efficiency measures and practices in such buildings is of utmost priority. Given the direct relationship of amount energy consumption and occupant comfort level in residential buildings, energy saving and energy efficiency is of increasing importance specifically in the residential sector. In this study, the combination of building information modeling (BIM) and building performance modeling (BPM) is used to identify appropriate dimensions and building materials to reduce energy in the lifecycle of a building. To perform this modeling, we evaluated various software applications used in different studies and after identifying their advantages and disadvantages, finally we chose Autodesk Revit and Autodesk Ecotect. In addition, suitable building materials and optimum sizes are determined corresponding to different weather conditions and climates in Iran. In another part of this study, the breakdown of energy consumption in the commercial and residential areas in Iran is examined. Given the 38% share of space heating in total building energy consumption, the important role of thermal insulation of external walls is emphasized. The effect of insulating in this region is calculated and marked using simulation of energy consumption. Using a suitable insulation system, can save 35% in lifecycle energy consumption.
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Experimental Study for Strength Capacity of Cold-Formed Steel Joists
           Connections with ...

    • Abstract: With growth the construction technologies, Cold-Formed Steel, CFS, sections are widely used in ordinary steel buildings because of some advantages such as light weight, ease of installation, decrease in cost, and increase in speed of operation. Using the bolted connections for CFS joist is one of the best details for steel structures. The main objective of this study is to conduct an experimental research to evaluate the load carrying capacity of bolted connections based on various bolts arrangement. Ten full scale joist-beam connections are tested under the incremental gravity load. The variable parameters are the arrangement of bolts, and thickness of CFS sheets. The joist sections made of two C-shaped, which are back-to-back connected using self-drilling screw bolts in the web. The arrangement of bolts connection and steel sheet thickness are considered as two major factors to improve the load carrying capacity. Base on the obtained results, it was observed that increasing the number of the bolts and their spacing from the neutral axes led to the additional load carrying capacity. Furthermore, it can be concluded that the thickness of CFS sheets play an effective role for load carrying capacity of connections.
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • A Method for Predicting Pile Capacity Using Cone Penetration Test Data

    • Abstract: The massive construction in poor lands has encouraged engineers to use deep foundations in order to transfer superstructure loads to the subsoil. Since soil excavation, sampling, and laboratory testing as a part of site investigation are relatively difficult, in-situ tests such as cone penetration test (CPT) as a very informative test may be recommended. The CPT has been widely used in engineering as a part of site investigation, and its data has been used to determine the axial capacity of piles. In this paper, the prediction capability of three empirical widely famous old methods used to predict the axial pile capacity based on CPT data is evaluated by using field data obtained from direct field pile loading tests. In this evaluation, the direct pile load test results are used as measured data. Three popular famous statistical evaluation methods namely the best-fitted line, geometric mean, and geometric standard deviation have been used. The evaluation results indicate that generally although predicting methods based on CPT data have been widely used to determine the axial bearing capacity of piles, they need to be upgraded for the economic and relatively accurate design of piles. According to the statistical studies carried out in the current research, among three old empirical methods, although the Nottingham and Schmertmann Method (1975, 1978) (NSM) [7, 8] has the best agreement with test results, it is felt that the method needs to be upgraded. The modification of NSM has been done in the current paper using a comprehensive database.
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Free vibration analysis of steel framed structures

    • Abstract: This study based on free vibration analysis and study the behavior of framed structure under different frequency of vibration using ANSYS software and shaking table. A small scale uni-axial shaking table was prepared in laboratory, which can produce lower to moderate vibration, regarding frequency and velocity. Moment resisting framed structures constructed with connecting beam and column elements of mild steel wire of different dimensions were tested in shaking table and analyzed using ANSYS software. The effect of masses and stiffness of structures on its natural frequency and deflection under certain ground vibration also studied and discussed. The test results showed that, this shaking table is satisfying the general concept of free vibration. The height of structures has an inverse effect on its natural frequency for same lateral stiffness. After several shaking, structure’s natural frequency started to decreases with their decreasing stiffness. Therefore, the fabricated shaking table can used in free vibration analysis.
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Effects of the opening on the behavior of composite shear walls

    • Abstract: Due to architectural, mechanical and even structural considerations, in some cases there is need to create some openings in the composite steel shear walls. Presence of the openings can considerably affect the wall behavior. Therefore in this study, the effects of the opening on the behavior of composite steel shear walls are investigated. For this purpose, first an experimental specimen without opening is developed and tested. The outcomes of the experimental study are verified by those obtained by Arabzadeh et al. [3]. Then four series of the CSPSW specimens with opening are built and tested. Accuracy and precision of these experimental results is verified by various numerical models which are developed using ABAQUS software. Therefore, general behavior of the CSPSWs with opening are investigated according to the attained results from numerical and experimental tests. In addition, some methods are proposed to reduce the negative effects of the opening on the behavior of CSPSW. Finally a parametric study is performed to study the effects of different parameters namely concrete cover thickness, steel plate thickness, thickness of the strengthening plate installed around the opening and bolt spacing on general behavior of the CSPSW
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Seismic Fragility Assessment of Steel SMRF Structures under Various Types
           of Near Fault Forward ...

    • Abstract: In this paper, the seismic collapse probability of special steel moment-resisting frame (SSMRF) structures under near fault pulse-like and far fault ordinary ground motions is evaluated through fragility analysis. For this purpose, five sample frames with 3 to 15 stories are designed and imposed to the ground motion excitations with different characteristics. Fragility curves are derived for the sample frames using the results of incremental dynamic analyses. Three sets of ten near fault ground motions with different range of pulse periods and one set of ten ordinary ground motions are used in dynamic analyses. Based on the obtained results, it was found that the impulsive characteristic and the pulse period of the records highly affect the damaging potential of near fault records. The fragility analysis reveals that the collapse probability for the case study frames under the near and far fault ground motions at the intensity of 0.35g equals to 4.3% and 10.3%, respectively. These values are 15.9%and 38.6%, for PGA of 0.53g. It is also found that the increase in the height, leads to increase in higher modes effect to transfer drift demands toward upper stories.
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Seismic evaluation of reinforced concrete moment frames retrofitted with
           steel braces using IDA ...

    • Abstract: One of the methods for retrofitting reinforced concrete moment frames is the use of steel braces. In this research, the seismic performance of a double-skinned concrete framing system reinforced with two concentric (CBF) and eccentric (EBF) steel bracing, was investigated under seven near-fault earthquake records of varying intensity. For this purpose, two ten-story concrete frames with five spans were designed according to the rules of procedure and were subjected to increasing dynamical analysis (IDA). Locating the braces in the first and fifth spans. The results indicate that reinforcing concrete frame using CBF and EBF braces increases the frame capacity by 2.3 and 2 times, respectively. The use of EBF braces in a concrete frame reduces up to 7 times the amount of base shear applied to the building relative to the CBF frame. Approximately, the displacement of the roof in the EBF frame in the near-fault area is less than the CBF frame. Also, the softer behavior of the EBF frame against earthquake records increases the safety and level of performance of the concrete bending frame at the immediate occupancy (IO).
      PubDate: Sun, 15 Apr 2018 19:30:00 +010
  • Evaluation of Dynamic Shear Rheometer Test parameters and Effect of Carbon
           Black Particles ...

    • Abstract: Using 100% of recyclable materials in road construction, protecting the environment, is an influential factor in the decision-making process for road projects. As one of the most important elements in nature and an original basis for the formation of life on earth, Carbon has been used in many different industries for its high surface area and porosity. Because of asphalt binder rheology characteristics, asphalt layers tend to return to their initial conditions after traffic flow but some of these deformations return in elastic form and some not return in plastic form. In this research, the Dynamic Shear Rheometer (DSR) test was used to analyze asphalt Binder performance Grade. Carbon Black particles processed from agricultural waste recycling (walnut skin) with specific weight percentages of 3, 5, 7 and 10, were used for asphalt binder rehabilitation. According to the results, the use of Carbon Black particles derived from the recycling of agricultural waste improves asphalt binder performance Grade from PG64 to PG74 for modified asphalt binder with 7% carbon black and rheological parameters like complex modulus increased 1.7 times and phase angle decreased approximately 0.85 times.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Experimental comparison of sacrificial piles and submerged vanes as scour
           countermeasures ...

    • Abstract: An experimental study has been conducted on the effectiveness of two types of flow-altering countermeasures placed around a cylindrical pier under clear water condition, which include sacrificial piles and submerged vanes. Their arrangements follow the optimal configurations recommended in the published articles with some modification. The temporal evolution of maximum scour depth and its equilibrium amount around the pile without and with two scour countermeasures were recorded; scour depth reduction rates and changes in bed topography were then calculated. It can be said that according to the result which has been earned from the experiments of this study, submerged vanes had better performances compare with the sacrificial piles in all of investigated aspects. By using submerged vanes 75% of the scour only occurred in first 5 minute. Presence of submerged vanes played more efficient role in reducing scour depth as subjected scour depth reduction was 17% more than one subjected to sacrificial piles. The length of changes downstream the pier (L) were 12, 13.2 and 6 times of pier diameter (D) corresponding to pier with no protection, sacrificial piles and submerged vanes respectively, which showed the effectiveness of submerged vanes in reducing the area affected by pier scour. Also the maximum changes of bed level were -6.9 cm to 3.9 cm in unprotected pier test, -4.4 to 3.5 cm in protection by sacrificial piles test and -3 to 3.2 cm in protection by submerged vanes.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Effect of the frequency content of earthquake excitation on damage
           detection in steel frames

    • Abstract: In this study, the effect of earthquake frequency content and noise effects on damage detection has been investigated. For this purpose, the damage was defined as nonlinear behavior of beams and columns, and several ground motion records were scaled so that some elements yield under the applied excitation. Then the acceleration response data of each floor obtained using the nonlinear dynamic analysis. Using the discrete wavelet analysis, the occurrence and time of damage in a frame can be detected based on the spikes appearing in the wavelet details plots obtained from discrete wavelet decomposition. The mean period (Tm) was used to determine the frequency content of earthquakes. The implications of this parameter for the analyses with different ground motion records were investigated and the results showed that the records with low Tm are more suitable for structural damage detection. To investigate the effect of noise or measurement errors on damage detection process, the discrete wavelet analysis was repeated with a noise introduced to the acceleration response data.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • New Lateral Force Distribution for Seismic Design of Structures Based on
           Seismic Demand Ratio

    • Abstract: The design of earthquake-resistant buildings starts with defining the maximum lateral earthquake forces or their resultant. The amount of these forces depends on various factors, including coefficient of system behavior which depends on overstrength and its ductility. In this study, a method is presented for designing an earthquake-resistant system in which the distribution of lateral forces is adjusted based on equal distribution of the seismic demand ratio in structural elements for the optimum use of seismic capability of the structure. To this end, three types of 4-, 7-, and 10-story structures are used. First, the above-mentioned structures are designed based on gravity loads and then analyzed based on linear and nonlinear dynamic analyses, using the accelerograms of some major earthquakes. Following that, the average loading ratio to the allowed capacity of the elements of each story in linear analysis and the average ratios of plastic rotations to the allowed capacity of elements in nonlinear analysis are applied as the modified shear ratio in the Iranian National Seismic Code. Therefore, the new lateral loading distribution is measured and identified. Based on this new distribution, the above-mentioned structures are designed and their seismic behaviors are identified, using linear and nonlinear dynamic analyses of the same accelerograms. The findings indicate an improved seismic behavior of the beams and the columns. Moreover, the distribution of the seismic demand ratios attains more uniformity along the height of the structures.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • An experimental and numerical study on the bearing capacity of circular
           and ring footings on ...

    • Abstract: This paper presents the results of a series of small-scale model tests and numerical analyses conducted on circular and ring model footings located near geogrid reinforced sand slopes. Layers of geogrid were used as reinforcement. For numerical analyses Finite Element Method (FEM) was used. The effects of reinforcement depth, size, number of layers, and the horizontal distance between reinforcement and the slope surface were experimentally investigated. Additionally, the effects of other parameters such as slope angle, the distance of the footing from the slope crest (for circular footings) and the ratio of inner to outer diameters (for ring fittings) were also investigated, numerically. The results of numerical analyses were compared with the laboratory test results and found to be in fair agreement. Optimum bearing capacity values were found for some studied parameters. The results indicate that if the reinforcement layers are implemented correctly, the bearing capacity of circular and ring footings over slopes would significantly increase.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • On the Local Scour around Group Piers in Series by Experimental Tests

    • Abstract: In this research a physical model is presented. A trapezoidal shape of channel with 1.45 m width, 1 meter depth and banks slope of 1H: 1.5V was used. Circular piers (6, 8 and 10cm diameter) were tested under three different flow discharges of 50, 65 and 80 lit/s and three different median bed material sizes equal to 0.94, 1.31 and 2.12 mm. Seven different longitude distance to pier diameter ratios (1, 1.5, 2, 2.5, 3, 4 and 5) were tested. Measurement of scour depth (upstream, around and downstream of pier) was accomplished in 10, 15, 20, 30, 60, 120, 240 and 360 minutes from the beginning of each test. The results showed that 30% to 40%, 55% to 65% and more than 90% of local scour occurs at first two minutes, at first 10 minutes and 120 to 200 minutes from the beginning of test respectively. The effect of different parameter especially the distance between piers on scour depth at group piers in series was evaluated and the results were compared to other investigators. It was found that our results is best fitted with the general form of well known Sheppard et al. (2004)’s equation.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Testing and numerical modelling of Steel-Concrete-Steel with stud bolts
           connectors subject to ...

    • Abstract: Steel-concrete-steel (SCS) sandwich panels are composed of two steel plates with low thicknesses and high densities and strengths and one thick layer between both plates with low strength and density known as core that is composed of concrete. Cohesive material-epoxy resin or shear connectors are usually used to connect the plates to the concrete core. SCS sandwich composites are being developed to be used in offshore structures and buildings. Stud bolt is one of the shear connectors and their interlayer shear behavior is studied in the present study. To investigate the effect of parameters on interlayer shear behavior of steel-concrete-steel sandwich structure with stud bolt connectors, push-out test is performed under progressive loading.According to the tests performed, relations are proposed to predict ultimate shear strength and load-slip behavior of samples with stud bolt shear connectors.Then, numerical model of push-out test is presented on the basic component of Steel-Concrete-Steel sandwich structure (SCS) with stud bolt connectors. The results showed that finite element model is consistent with test results using mass scaling in Explicit Solver with a suitable analysis speed. Using the regression analysis on the results of 80 numerical models of push-out test,a relation was proposed for shear strength of push-out samples with stud bolt connectors.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Evaluating the Performance of the Buckling Restrained Braces in Tall
           Buildings with ...

    • Abstract: In recent years, seismic design of structures has been undergoing significant changes due to increasing demand for optimization and minimizing the level of damage and reducing the cost of structural repairs. Development of analytical methods and remarkable improvements of computer performance have been among the factors which influenced the design of structures. A lot of research has been conducted on the development of braces with perfect elastoplastic behaviour. The invention and development of the buckling restrained braces have been the results of these researches. In this study, the performance of the Buckling Restrained Environmental Braces (BRB) in high-rise buildings were evaluated using nonlinear time-history dynamics analysis with three pairs of acceleration and compared with the conventional concentrically braced frame (CBF). The studied structures are 20, 40, and 60 stories building in which braces were utilized peripherally. The obtained results illustrate that the use of Buckling Restrained Brace Frames (BRB) instead of conventional braces frame (CBF) in high-rise steel buildings improves hysteresis behavior of the braces and reduces lateral displacements and also increase the capacity of base shear.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Seismic Rehabilitation of Liquid Storage Tanks using Friction Pendulum
           Base Isolation subjected ...

    • Abstract: Cylindrical liquid storage tanks are considered as vital structures in industrial complex whose nonlinear dynamic behavior is of crucial importance. Some of these structures around the world have demonstrated poor seismic behavior over the last decades. There are several methods and techniques for rehabilitation and reducing damages in these structures which among them passive control devices, in particular seismic base isolators, are noticeable. Friction Pendulum System (FPS) is the most popular base isolation system. In this paper, the effectiveness of FPS is studied on reducing the seismic responses of base isolated liquid storage tanks as well as the impact effect of slider to the side restrainer. To this end, the whole mass of liquid storage tank is considered as three lumped masses known as convective mass, impulsive mass which is connected to tanks with corresponding spring, and rigid mass which is connected rigidly. By means of state space method the time history analysis is done using 60 earthquake records to obtain dynamic responses under the different hazard levels i.e. SLE, DBE and MCE ground motions. The results show that the normalized base shear force in squat tank decreased 59%, 62% and 33% respectively under SLE, DBE and MCE ground motions. The reduction of normalized base shear force in slender tank is 53%, 49% and 35% under the aforementioned hazard levels. Examining the effect of side restrainer’s stiffness on the maximum responses show that the impact effect must be considered particularly when the system is excited by MCE’s ground motions.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Extraction of model parameters for reactive solute transport

    • Abstract: In the present study, tried to examine the reactive solute relationships for transport and degradation processes through the rockfill media. By applying the analytical solution of reactive transport, the 1st to 3rd theoretical temporal moments have been extracted then, by using two methods of curve fitting and temporal moment matching, the coefficients of dispersion and degradation have been exploited. Two rock diameter, two operating discharges and five instantly injection mass have been used as the variables of experiments. The EC sensors with operation software were installed inside the rockfill media and then the experimental breakthrough curves with intervals of 4 seconds have been extracted. It is concluded that both methods are suitable for application of transport and degradation processes inside the media. It was observed that by increasing inflow discharges, pore velocity, and media diameters the dispersion coefficient decreases and with a decrease in media diameter or with increase in injection mass the decay rate decreases. The sensitivity analysis on the derived moment equation and also skewness coefficient equation indicated that the velocity and degradation are the most and less effective parameters on the moment equations respectively
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • A laboratory investigation on the potential of computational intelligence
           approaches to ...

    • Abstract: The piano key weir (PKW) is a type of nonlinear control structure that can be used to increase unit discharge over linear overflow weir geometries, particularly when the weir footprint area is restricted To predict the outflow passing over a piano key weir, the discharge coefficient in the general equation of weir needs to be known. This paper presents the results of laboratory model testing of a piano key weir located on the straight open channel flume in the hydraulic laboratory of Bu-Ali Sina University. The discharge coefficient of piano key weir is estimated by using four computational intelligence approaches, namely, feed forward back-propagation neural network (FFBPN), an extension of genetic programming namely gene-expression programming (GEP), least square support vector machine (LSSVM) and extreme learning machine (ELM). For this purpose, 70 laboratory test results were used for determining discharge coefficient of piano key weir for a wide range of discharge values. Coefficient of determination (R2), Nash-Sutcliffe efficiency coefficient (NS), root mean square error (RMSE), mean absolute relative error (MARE), scatter index (SI) and BIAS are used for measuring the models’ performance. Overall performance of the models shows that, all the studied models are able to estimate discharge coefficient of piano key weir satisfactorily. Comparison of results showed that the ELM (R2=0.997 and NS= 0.986) and LSSVM (RMSE=0.016 and MARE=0.027) models were able to produce better results than the other models investigated and could be employed successfully in modeling discharge coefficient from the available experimental data.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • Assessing Seismic Performance of the Elliptic Braced Moment Resisting
           Frame through Pushover Method

    • Abstract: The seismic performance of elliptic braced moment resisting frame (ELBRF) is assessed here and is found that the structural behavior is improved and is of free of architectural space. The demand for seismic performance of ELBRF is estimated through conventional pushover methods of 3, 5, 7, and 10-story ELBRF frames and they are compared with special moment resisting frames (SMRF) and X-Braced CBF and Inverted V-Braced CBF concentrically braced frames. The effective parameters in the seismic design of structures, like the ductility, overstrength and response modification factors are evaluated. The response modification factor for ELBRF in the design by ultimate limit state and allowable stress methods is proposed as 10 and 14.4, respectively. Finally, the process of forming plastic hinges in ELBRF is assessed and it is found that an increase in height makes the plastic hinges to be transmitted to the upper stories, allowing the structure to collapse at higher stories.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
  • An optimal semi-active thermal exchange-Fuzzy logic Controller for
           Structural Dynamic Control ...

    • Abstract: The effect of intelligent semi-active thermal exchange-fuzzy controller in structural rehabilitation by attenuating seismic responses of structural systems is investigated. In the suggested control system, MR dampers and sensors are employed as a semi-active controller. Resultant control forces of MR damper are administrated by providing external voltage supply, during the earthquakes and high intensity winds. Moreover, a novel evolutionary algorithm of thermal exchange (TE) is utilized to optimize the placement and the number of MR dampers and sensors in the sense of minimizing resultant vibration magnitude. An optimal semi-active thermal exchange-Fuzzy logic Controller (TE-FLC) is introduced to manage MR damper intelligently. Results of numerical simulations illustrate the efficiency of suggested control system. The TE-FLC can determine the optimal control arrangement and forces during a reasonable number of iterations. In comparison of the performance of various control strategies, the TE-FLC demonstrates that economical cost and rehabilitation properties of the building could be optimized simultaneously. The TE-FLC managed the optimal control forces online during strong ground motion, to attenuate the excessive responses in several rehabilitated buildings. Hence, the TE-FLC could improve the reliability of rehabilitated structure in comparison with passive and offline controllers. The significant efficiency of optimal arrangement of dampers and sensors over uniformly distribution of damper and sensors is also illustrated.
      PubDate: Sun, 04 Feb 2018 20:30:00 +010
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
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