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Seismic Performance of Steel Plate Shear Walls Considering Various Design Approaches 14-0005 R. Purba and M. Bruneau MCEER-14-0005 | 10/31/2014 | 562 pages Keywords: In-span plastic hinge; Experimental; Steel plate shear walls; Seismic performance; Deterioration and failure modes; Deterioration model; Collapse potential; Collapse fragility curve; Seismic Performance Factors; Infill plate design; FEMA P695 Methodology Abstract: This report presents the results of experimental and analytical studies to investigate the seismic performance of steel plate shear walls (SPSWs) considering different design philosophies of horizontal boundary elements (HBEs) and infill plates. The experimental study on a three-story SPSW specimen showed the development of HBE in-span hinges which resulted in an accumulation of plastic incremental deformations. A finite element investigation on the tested SPSW specimen demonstrated similar behavior. Furthermore, collapse assessment of SPSWs with various structural configurations (e.g., panel aspect ratio, seismic weight intensity, and number of stories) was conducted to investigate impact of sharing of story shear forces between the boundary frames and infill plates on the performance of SPSWs. SPSWs designed with the current seismic performance factors specified in the ASCE 7-10 and neglecting the contribution of their boundary moment resisting frames to resist story shear forces met the FEMA P695 performance criterion, while that was not the case for SPSWs designed considering the sharing of story shear forces between the boundary frame and infill plates. Adjusted seismic performance factors were required for the latter SPSWs to rigorously meet the FEMA P695 performance criteria. Most importantly, the latter SPSWs were found to have a higher probability to suffer significantly larger interstory drift than the former. This research extends work reported in “Impact of Horizontal Boundary Elements Design on Seismic Behavior of Steel Plate Shear Walls” by R. Purba and M. Bruneau, MCEER-10-0007. The finite element analysis was performed using the software ABAQUS/Standard while the collapse assessment was performed using the software OpenSees. منبع دانلود Seismic_Performance_of_Steel_Plate.pdf

COMPARE THE BEHAVIOR FACTOR OF THE ULTIMATE RESISTANCE OF MOMENT FRAME, PLAIN AND PERFORATED STEEL PLATE SHEAR WALLS AND BUCKLING RESTRAINED BRACE AS YIELDING METAL DAMPER ABSTRACT: Steel moment frame systems, steel plate shear walls and also buckling restrained brace (BRB) are considered as the most widely used seismic resistant systems of the world. Firstly, in this research, in order to validate the finite element models, the tested sample of steel plate shear walls of 4 floors at the University of Alberta, Canada, and the tested sample of buckling restrained brace at the University of Berkeley California, with the software ABAQUS 6.10-1 were used. Then, the obtained results of the test and analysis have been compared. The confirmed models have been used for the analysis of two-dimensional frame of plain and perforated steel plate shear walls with a regular pattern of positing holes in the screen, buckling restrained brace and moment frame of 4 floors. منبع دانلود COMPARE THE BEHAVIOR.pdf

Optimal placement of steel plate shear walls for steel frames by bat algorithm Saeed Gholizadeh1*,† and Amir Masoud Shahrezaei2 1Department of Civil Engineering, Urmia University, Urmia, Iran 2Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Urmia, Iran SUMMARY Layout optimization of steel frames with steel plate walls (SPWs) using a meta-heuristic search algorithm is the main aim of the present study. SPWs are lateral load-resisting systems, especially against earthquake excitation. These systems offer significant advantages in terms of cost, performance and ease of design compared with other systems. In this study, orthotropic membrane model is used to model the behaviour of steel plate shear walls. The newly developed bat algorithm, which is based on the echolocation behaviour of bats, is employed as the present study optimizer. Design variables of the optimization problem consist of the cross sections of beams and columns of the frame, the web plate thicknesses of SPWs and the placement of SPW in the frame. The bat algorithm performs suitable selection of sections from the AISC wide-flange (W) shapes list. Strength constraints of the American Institute of Steel Construction Load and Resistance Factor Design and displacement constraints are checked during the optimization process. The results reveal the effectiveness of the proposed method for optimization of steel frames with SPWs. Copyright © 2014 John Wiley & Sons, Ltd. Received 29 July 2013; Revised 16 October 2013; Accepted 13 December 2013 gholizadeh2014.pdf

Seismic behavior of code designed steel plate shear walls Jeffrey W. Berman∗ Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195-2700, United States Engineering Structures 33 (2011) 230–244 AbstractThe AISC Seismic Design Provisions now include capacity design requirements for steel plate shear walls, which consist of thin web plates that infill frames of steel beams, denoted horizontal boundary elements (HBEs), and columns, denoted vertical boundary elements (VBEs). The thin unstiffened web plates are expected to buckle in shear at low load levels and develop tension field action, providing ductility and energy dissipation through tension yielding of the web plate. HBEs are designed for stiffness and strength requirements and are expected to anchor the tension field formation in the web plates. VBEs are designed for yielding of web plates and plastic hinge formation at the ends of the HBEs. This paper assesses the behavior of code designed SPSWs. A series of walls are designed and their behavior is evaluated using nonlinear response history analysis for ground motions representing different hazard levels. It is found that designs meeting current code requirements satisfy maximum interstory drift requirements considering design level earthquakes and have maximum interstory drifts of less than 5% for maximum considered earthquakes. Web plate ductility demands are found to be significantly larger for low rise walls than for high rise walls where higher modes of vibrations impact the response. The percentage of story shear resisted by the web plate relative to the boundary frame is found to be between 60% and 80% and is relatively independent of panel aspect ratio, wall height, or hazard level, but is affected by transitions in plate thickness. Maximum demands in VBEs in design level shaking are found to be considerably less than those found from capacity design for SPSWs with 9 or more stories. Research highlights► Steel plate shear walls designed via current building code requirements meet drift limitations. ► Web plate ductility demands in low-rise steel plate shear walls are significantly larger than those in taller steel plate shear walls. ► The percentage of story shear resisted by the web plates was found to range from 60–80% and is independent of aspect ratio, wall height and seismic demand but is affected by transitions in web plate thickness. ► Maximum demands in steel plate shear wall columns from nonlinear response history analysis are found to be considerably less than those determined from capacity design in steel plate shear walls with 9 or more stories. Keywords Steel plate shear walls; Seismic behavior; Ductility; Seismic design; Column demands; Steel structures; Shear walls 10.1016_J.ENGSTRUCT.2010.10.015-Seismic-behavior-of-code-designed-steel-plate-shear-walls.pdf