Structural Engineering and Mechanics最新文献_第2页

Seismic performance of L-shaped RC walls sustaining Unsymmetrical bending 承受不对称弯曲的l形钢筋混凝土墙的抗震性能

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.78.3.269

Zhongwen Zhang, Bing Li

{"title":"Seismic performance of L-shaped RC walls sustaining Unsymmetrical bending","authors":"Zhongwen Zhang, Bing Li","doi":"10.12989/SEM.2021.78.3.269","DOIUrl":"https://doi.org/10.12989/SEM.2021.78.3.269","url":null,"abstract":"Reinforced concrete (RC) structural walls with L-shaped sections are commonly used in RC buildings. The walls are often expected to sustain biaxial load and Unsymmetrical bending in an earthquake event. However, there currently exists limited experimental evidence regarding their seismic behaviour in these lateral loading directions. This paper makes experimental and numerical investigations to these walls behaviours. Experimental evidences are presented for four L-shaped wall specimens which were tested under simulated seismic load from different lateral directions. The results highlighted some distinct behaviour of L-shaped walls sustaining Unsymmetrical bending relating to their seismic performance. First, due to the Unsymmetrical bending, out-of-plane reaction forces occur for these walls, which contribute to accumulation of the out-of-plane deformations of the wall, especially when out-of-plane stiffness of the section is reduced by horizontal cracks in the cyclic load. Secondly, cracking was found to affect shear centre of the specimens loaded in the Unsymmetrical bending direction. The shear centre of these specimens distinctly differs in the flange in the positive and negative loading direction. Cracking of the flange also causes significant warping in the bottom part of the wall, which eventually lead to out-of-plane buckling failure.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"78 1","pages":"269"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66125529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Evaluation of required seismic gap between adjacent buildings in relation to the Egyptian Code 与埃及规范相关的相邻建筑物之间所需地震间隙的评估

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.78.2.219

M. Hussein, Ahmed Mostafa, W. Attia

{"title":"Evaluation of required seismic gap between adjacent buildings in relation to the Egyptian Code","authors":"M. Hussein, Ahmed Mostafa, W. Attia","doi":"10.12989/SEM.2021.78.2.219","DOIUrl":"https://doi.org/10.12989/SEM.2021.78.2.219","url":null,"abstract":"International seismic codes stipulate that adjacent buildings should be separated by a specified minimum distance, otherwise the pounding effect should be considered in the design. Recent researches proposed an alternative method (Double Difference Combination Rule) to estimate seismic gap between structures, as this method considers the cross relation of adjacent buildings behavior during earthquakes. Four different criteria were used to calculate the minimum separation distance using this method and results are compared to the international codes for five separation cases. These cases used four case study buildings classified by different heights, lateral load resisting systems and fundamental periods of vibrations to assess the consistency in results for the alternative methods. Non-linear analysis was performed to calculate the inelastic displacements of the four buildings, and the results were used to evaluate the relation between elastic and inelastic displacements due to the ductility of structural elements resisting seismic loads. A verification analysis was conducted to guarantee that the separation distance calculated is sufficient to avoid pounding. Results shows that the use of two out of the four studied methods yields separation distances smaller than that calculated by the code specified equations without under-estimating the minimum separation distance required to avoid pounding.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"78 1","pages":"219"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66125637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Output only system identification using complex wavelet modified second order blind identification method - A time-frequency domain approach 输出仅系统辨识利用复小波修正二阶盲辨识方法-一种时频域方法

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.78.3.369

C. Huang, Satish Nagarajaiah

引用次数: 0

Feasibility study of buckling-restrained braces with PM-35 steel core PM-35型钢芯抗屈曲支撑的可行性研究

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.79.2.199

Chao Zhao, Qianqiang Chen, Xingu Zhong, Tianyu Zhang, Zhiwen Chen

{"title":"Feasibility study of buckling-restrained braces with PM-35 steel core","authors":"Chao Zhao, Qianqiang Chen, Xingu Zhong, Tianyu Zhang, Zhiwen Chen","doi":"10.12989/SEM.2021.79.2.199","DOIUrl":"https://doi.org/10.12989/SEM.2021.79.2.199","url":null,"abstract":"The energy dissipation characteristics of core materials greatly influence the working performance of bucklingrestrained braces (BRBs), so it is a vital work to develop more excellent energy dissipation core materials. In this research, a series of experimental studies are conducted, including the mechanical properties of PM-35 steels and the working performance of PM-35 BRB specimens, which serve to investigate the feasibility of PM-35 steel as core materials of BRBs. In addition, the analysis of variance (ANOVA) has been conducted to study the sensitivity factors of energy dissipation of PM-35 BRB specimens, especially the pre-force applied on the BRB specimens. According to the results of this research, it can be concluded that the energy absorption efficiency of PM-35 BRBs specimens is much higher than that of BRB specimens with ordinary core materials; the internal pores greatly weaken the yield strength of PM-35 steel and obviously improve the plastic deformation capacity, which makes that PM-35 core materials are able to absorb energy in a lower stress level; pre-force applied on core materials is the key factor governing the energy absorption, and can significantly improve the working performance of BRB specimens with PM-35 core materials.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"79 1","pages":"199"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66127810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Designing and experimental study of compact vibration isolator with quasi-zero stiffness 准零刚度紧凑型隔振器的设计与试验研究

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.79.4.415

A. Valeev, R. Tashbulatov, B. Mastobaev

{"title":"Designing and experimental study of compact vibration isolator with quasi-zero stiffness","authors":"A. Valeev, R. Tashbulatov, B. Mastobaev","doi":"10.12989/SEM.2021.79.4.415","DOIUrl":"https://doi.org/10.12989/SEM.2021.79.4.415","url":null,"abstract":"This study aimed to develop a compact high-efficiency vibration isolator. It was proposed to use force characteristic with quasi-zero stiffness. To avoid a number of design problems, the isolator was designed in a dome shape. This study features a mathematical model of the vibration isolator with quasi-zero stiffness. It allows calculating the isolator properties by geometrical parameters. Stability analysis giving advanced formulas for achieving the maximum workload at certain dimensions was made. For an experimental study, the prototypes were made of shock-absorbing rubbers IRP1346, IRP1347, IRP1348, and fluoroelastomer SKF-32. Force characteristic in static condition was studied, which showed the high efficiency of the compact vibration isolator with quasi-zero stiffness: natural frequency equals 0.8-1.2 Hz. An experimental study in dynamic condition was done using load cell sensors to measure dynamic force transmitted with and without the vibration isolator. The experiment shows a vibration isolation coefficient equal to 244, corresponding to the natural vibration frequency of 2.17 Hz. The study shows the vibration isolator with quasi-zero stiffness as highly efficient, compact, and very perspective for industrial application.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"79 1","pages":"415"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66129122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Mechanical properties and bearing capacity of CFRP confined steel reinforced recycled concrete columns under axial compression loading 轴压荷载作用下CFRP约束钢增强再生混凝土柱的力学性能与承载力

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.79.4.451

Hui Ma, Yanan Wu, Cheng Huang, Yanli Zhao

{"title":"Mechanical properties and bearing capacity of CFRP confined steel reinforced recycled concrete columns under axial compression loading","authors":"Hui Ma, Yanan Wu, Cheng Huang, Yanli Zhao","doi":"10.12989/SEM.2021.79.4.451","DOIUrl":"https://doi.org/10.12989/SEM.2021.79.4.451","url":null,"abstract":"To study the axial compression behavior of carbon fiber reinforced plastics (CFRP) confined steel reinforced recycled concrete (CSRRC) columns, 11 specimens of CSRRC columns were manufactured and tested under axial compression loading. The design variables in the experiments included the replacement percentage of recycled coarse aggregate (RCA), layers of CFRP, strength of recycled aggregate concrete (RAC), profile steel ratio and slenderness ratio. Subsequently, the failure process and modes, load-displacement curves, stress-strain curves, transverse deformation coefficient and stiffness degradation of the specimens were obtained and analyzed in detail. The experimental results showed that the profile steel yielded before the steel rebars in the columns, then the RAC was crushed, and finally the CFRP broke under axial compression loading. The axial bearing capacity of CSRRC columns decreased with the increase of replacement percentage of RCA and slenderness ratio, respectively. However, the CFRP can give full play to its high-strength confinement performance and effectively improve the axial bearing capacity and deformability of columns. Moreover, the profile steel ratio and strength of RAC have significant effects on the initial stiffness of CSRRC columns, and the stiffness degradation rate of columns decreases with the increase of these parameters. Overall, the CSRRC columns exhibit high axial bearing capacity and good ductility deformation ability. Based on ACI 440.2R-08, the modified formula on the nominal axial bearing capacity of CSRRC columns was proposed in this study. The accuracy on the modified formulae was evaluated by the comparison between the calculated values and test values.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"79 1","pages":"451"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66129314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Development of a lattice model for predicting nonlinear torsional behavior of RC beams 预测钢筋混凝土梁非线性扭转性能的格点模型的建立

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.79.6.779

Yeongseok Jeong, M. Kwon, Jinsup Kim

{"title":"Development of a lattice model for predicting nonlinear torsional behavior of RC beams","authors":"Yeongseok Jeong, M. Kwon, Jinsup Kim","doi":"10.12989/SEM.2021.79.6.779","DOIUrl":"https://doi.org/10.12989/SEM.2021.79.6.779","url":null,"abstract":"Seismic design criteria based on performance of structures have recently been adopted by practicing engineers in response to destructive earthquakes. A simple but efficient structural-analysis tool capable of predicting both strength and ductility is needed to analyze reinforced concrete (RC) structures subjected to such events. Hence, a three-dimensional lattice model is developed in this study to analyze torsions in high-strength RC beams. Optimization techniques for determining optimal variables in each lattice model are introduced. Pure torsion tests of RC beams were performed to use to propose a threedimensional lattice model. The experimental test results of pure torsion on RC beam specimens were used to compare with numerical results obtained using the proposed model. Then, the proposed model was also compared to 3D solid model in commercial finite element analysis program, ABAQUS. Correlation studies between the numerical and experimental results confirm that the proposed model is well capable of representing salient features of the experimental results. Furthermore, the proposed model provides better predicted displacement corresponding to peak load. than the result from ABAQUS.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"79 1","pages":"779"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66130803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hygrothermal stress analysis of laminated composite porous plates 层合复合多孔板的湿热应力分析

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.80.1.001

Y. Yüksel, Ş. Akbaş

引用次数: 2

Practical method for determining load and resistance factorsusing third-moment transformation 用三阶矩变换确定负载和电阻因数的实用方法

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.80.2.143

Pei-Pei Li, Zhao-Hui Lu, Yan-Gang Zhao

{"title":"Practical method for determining load and resistance factorsusing third-moment transformation","authors":"Pei-Pei Li, Zhao-Hui Lu, Yan-Gang Zhao","doi":"10.12989/SEM.2021.80.2.143","DOIUrl":"https://doi.org/10.12989/SEM.2021.80.2.143","url":null,"abstract":"Load and resistance factor design (LRFD) is a suitable format for the reliability-based limit state design of structures. It has been adopted in many countries, such as the United States, Europe, Canada, and Japan. Usually, the first-order reliability method (FORM) is used to estimate the load and resistance factors, but it requires the determination of design points and complicated double iterative computations. Therefore, FORM is not easy or practical for engineers to use. This paper presents a simple, accurate method to determine the load and resistance factors utilizing the third-moment transformation, which does not require derivative-based iterations and can estimate the load and resistance factors without using the distribution of random variables. In addition, the proposed method provides enough accurate results within a wide range of target reliability indices. Therefore, this method should be effective and convenient for calculating the load and resistance factors in actual practice. Five numerical examples illustrate the proposed method's efficiency and accuracy; FORM provides a benchmark for comparison.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"80 1","pages":"143"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66131205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A reliability-based fragility assessment method for seismic pounding between nonlinear buildings 基于可靠性的非线性建筑物间地震冲击易损性评估方法

IF 2.2 4区工程技术

Structural Engineering and Mechanics Pub Date : 2021-01-01 DOI: 10.12989/SEM.2021.77.1.019

Pei Liu, Hai-xin Zhu, Peng-Peng Fan, W. Yang

{"title":"A reliability-based fragility assessment method for seismic pounding between nonlinear buildings","authors":"Pei Liu, Hai-xin Zhu, Peng-Peng Fan, W. Yang","doi":"10.12989/SEM.2021.77.1.019","DOIUrl":"https://doi.org/10.12989/SEM.2021.77.1.019","url":null,"abstract":"Existing methods to estimate the probability of seismic pounding occurrence of adjacent buildings do not account for nonlinear behavior or only apply to simple lumped mass systems. The present study proposes an efficient method based on subset simulation for fragility and risk assessment of seismic pounding occurrence between nonlinear adjacent buildings neglecting pounding effects with application to finite element models. The proposed method is first applied to adjacent buildings modeled as elastoplastic systems with substantially different dynamic properties for different structural parameters. Seismic pounding fragility and risk of adjacent frame structures with different floor levels is then assessed, paying special attention to modeling the non-linear material behavior in finite element models. Difference in natural periods and impact location are identified to affect the pounding fragility simultaneously. The reliability levels of the minimum code-specified separation distances are also determined. In addition, the incremental dynamic analysis method is extended to assess seismic pounding fragility of the adjacent frame structures, resulting in higher fragility estimates for separation distances larger than the minimum code-specified ones in comparison with the proposed method.","PeriodicalId":51181,"journal":{"name":"Structural Engineering and Mechanics","volume":"77 1","pages":"19-35"},"PeriodicalIF":2.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66120108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1