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Hysteretic Analysis of Steel Plate Shear Walls (SPSWs) and A Modified Strip Model for SPSWs Lanhui Guo1,*, Ran Li1,2, Sumei Zhang1 and Guirong Yan3 1School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China 2China Academy of Building Research, Beijing 100013, China 3School of Engineering, University of Western Sydney, Penrith, NSW 1797, Australia (Received: 7 April 2010; Received revised form: 14 February 2012; Accepted: 16 February 2012) Abstract: Steel plate shear walls (SPSWs) have become more and more popular in recent years because of their potential huge energy dissipation capacity and ductility under lateral loads. Due to their low cost and fast construction, SPSWs have potential application in practice. The finite element software ANSYS applied to the analysis of the hysteretic behavior of SPSWs is described in this paper first. It was found that compressive stress existed in SPSWs and the effects became more evident with decreasing height-to-thickness ratio. This was validated by comparing theoretical and experimental test results. Secondly, based on the analytical results, a modified strip model is proposed. In the modified model, the compressive effects in the panel were taken into account and it was then found that the load-carrying capacity and the energy dissipation capacity agreed well with the already carefully validated experimental results. Key words: finite element (FE), steel plate shear wall (SPSW), hysteretic behavior, strip model, energy dissipation capacity. 1369-4332.15.10.1751.pdf

Experimental and numerical study of unstiffened steel plate shear wall structures Meng Wang a,⁎, Yongjiu Shi b, Jian Xu c,Weiguo Yang a, Yixin Li b a School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China b Department of Civil Engineering, Tsinghua University, Beijing 100084, China c China Southwest Architectural Design and Research Institute Corp. LTD, Chengdu 610081, China a r t i c l e i n f o a b s t r a c t Article history: Received 13 March 2015 Accepted 6 May 2015 Available online 20 June 2015 Keywords: Unstiffened thin steel plate shear wall structure Hysteretic behavior Energy dissipation capacity Ductility Finite element method (FEM) Column stiffness In order to investigate the seismic behaviors of unstiffened thin steel plate shear wall structure, tests of four three-story unstiffened steel plate shear wall specimens under cyclic loads were carried out. Parameters of the specimens included height-to-thickness ratio, span-to-height ratio and middle brace. The carrying capacity, hysteretic behavior, degraded characteristics, ductility, failuremodes, energy dissipation capacity were analyzed and compared deeply. Besides, the nonlinear finite element method of shear wall structure was also established, which was verified by test results. Finally, the effect of column stiffness on load-carrying capacity was studied. The practical requirements of in-plane and out-of-plane stiffness of edge column were suggested. The experimental and numerical results showed that: this kind structure exhibits high strength, good energy dissipation capacity, and good ductility (the ductility coefficients are more than 3.0). When the inter-story drift angle reaches 1/50, the strength degradation is no more than 5%, indicating that the structure has good seismic behaviors. The span-to-height ratio has little effect on load-carrying capacity, while slightly affects the initial stiffness and ductility. The effect of height-to-thickness ratio (thickness) on load-carrying capacity is relatively larger than other factors. The middle braces do not improve the behaviors of structures. The stiffness of edge column has great effect on lateral load-carrying capacity of shearwall structures. The value of column stiffness index could bewithin 2.0–2.5 to achieve the sufficient constraints and economical benefit. 1-s2.0-S0143974X15001406-main.pdf

Seismic behaviors of steel plate shear wall structures with construction details and materials Wang Meng a,⁎, YangWeiguo a, Shi Yongjiub, Xu Jian c a School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China b Department of Civil Engineering, Tsinghua University, Beijing 100084, China c China Southwest Architectural Design and Research Institute Corp. Ltd, Chengdu 610081, China a r t i c l e i n f o a b s t r a c t Article history: Received 3 May 2014 Accepted 8 January 2015 Available online 23 February 2015 Keywords: Steel plate shear wall structure Structural construction detail Low yield point steel T type stiffened ribs Finite element method (FEM) Hysteretic behavior In order to have a systematic and comprehensive comparison of seismic behaviors of steel plate shear wall structures with different construction details, a numerical method was proposed, which was proved accurately to predict the performance of structures with published quasi-static tests. Then, eight typical steel shear wall models with different structural construction details were established. Also an advanced stiffened low yield point steel plate shear wall was proposed to avoid excessive out-of-plane deformation. The seismic behaviors of above nine shear wall models were fully compared and analyzed, and key issues, such as energy-dissipating capacity, ductility, out-of-plane deformation and the effect of tension field on the columns were discussed in depth. The results showed that: in high-intensity seismic area, load-carrying capacity, hysteretic behaviors, failure modes, seismic ductility and economic performance should be taken into account comprehensively to choose the appropriate form of steel plate shear wall structure; the proposed low yield point steel plate shear wall with T type stiffened ribs could most effectively improve the energy dissipation capacity and ductility, and lessen the impact of tension field on the columns, besides, it had better load-carrying capacity and smallest out-of-plane deformation. This method provided a good way for improving the seismic behaviors of steel shear wall structures. 1-s2.0-S0143974X15000097-main.pdf

Toward buckling free tension-only braces using slack free connections Seyed Amin Mousavi a, Seyed Mehdi Zahrai a,⁎, Murat Saatcioglu b a School of Civil Engineering, College of Engineering, The University of Tehran, P.O. Box 11155-4563, Tehran, Iran b Department of Civil Engineering, The University of Ottawa, Ottawa KIN 6N5, Canada a r t i c l e i n f o a b s t r a c t Article history: Received 15 July 2014 Received in revised form 25 August 2015 Accepted 28 August 2015 Available online xxxx Keywords: Tension-only brace Buckling free Hysteretic behavior Energy dissipation Seismic behavior Slack free connection This study introduces a slack free connection (SFC) by which pinchingwould be removed fromhysteretic behavior of tension-only braces (TOBs). SFC through its mono-directional behavior, eliminates undesirable pinching of the tension-only bracing and changes it to a reliable lateral load resisting system with high energy dissipation capability. A Matlab/Simulink-based model, called Macro-Simulink model, is developed to simulate hysteretic behavior of TOBs with orwithout SFC. Derived Macro-Simulink model is also able to account for hysteretic behavior of the frame. The frame itself can have either deteriorated or non-deteriorated hysteretic behaviors. The Macro- Simulink model is verified through different techniques including earlier experimental results, explicit finite element modeling, and other pre-verified analytical/numerical tools. It is observed that initial pre-tension load only affects initial stiffness of the TOB and has no contribution on its nonlinear hysteretic behavior. Obtained results of this study indicate that energy dissipation capacity of TOBs with SFC would be improved up to 6 times compared with that of conventional TOBs. Moreover contribution of SFC is more pronounced in the case of frames with highly deteriorated behaviors. As a result TOB with SFC can be considered for retrofit purposes as well. منبع [Hidden Content] دانلود: [Hidden Content] EoGZ7fgV.pdf

Evaluation of hysteretic behavior of eccentrically braced frames with zipper-strut upgrade Seyed Mehdi Zahrai a, Milad Pirdavari b,⁎, Hamid Momeni Farahani b a Center of Excellence for Management and Engineering of Civil Infrastructures, School of Civil Engineering, College of Engineering, The Univ. of Tehran, P.O. Box 11365/4563, Tehran, Iran b Ati-Naghsh Hamraz Consultants, Inc. Suite 8, No. 73, Jalale Ale Ahmad, P.O. Box 1446665718, Tehran, Iran a r t i c l e i n f o a b s t r a c t Article history: Received 28 August 2012 Accepted 28 December 2012 Available online xxxx Keywords: EBF Zipper strut Hysteretic behavior Pushover analysis Finite-element Cyclic loading This paper describes the seismic behavior of Eccentrically Braced Frames (EBF) upgraded using zipper-struts which connect the mid-point of shear links in all stories. The numerical modeling of the zipper-strut-equipped model is conducted using finite-element method software under cyclic load, with the goal of evaluating the behavior of shear links. The interaction of shear links and zipper-struts is also studied. Furthermore, the prototypes are subjected to nonlinear static (Pushover) analysis in two configurations; one with moment-resisting connections and one with pinned connections. Finally, the increase of ductility coefficient for the prototypes with zipper-strut is studied. The prototypes are also subjected to time-history analysis using scaled earthquake records, with the purpose of studying the energy parameters of the models. The unbalanced shear force is distributed among all stories due to the added continuity among shear links. This results in the extension of structural displacement capacity according to acceptance criteria. Moreover, a noticeable delay occurs until shear links experience enough rotation to meet Collapse Prevention acceptance criteria. By imposing acceleration on the structure and conducting time history analysis, it is observed that the zipper-strut-equipped system shows a stronger tendency to form shear links, leading to greater dissipation capacity in plastic zone Journal of Constructional Steel Research 83 (2013) 10–20 منبع: [Hidden Content] دانلود: [Hidden Content] media.pdf