جستجو در تالارهای گفتگو
در حال نمایش نتایج برای برچسب های 'shear walls'.
3 نتیجه پیدا شد
Failure analysis of RC shear walls with staggered openings under seismic loads تحلیل گسیختگی دیوارهای برشی بتن مسلح با بازشوهای شطرنجی در بارهای لرزه ای Marius Mosoarca a b s t r a c t Reinforced concrete shear walls are used to design buildings located in seismic areas, because of their rigidity, bearing capacity and high ductility. Until now many theoretical and experimental tests on shear walls with or without openings have been made, therefore their failure modes have been analysed and are rather very well-known; the research results being confirmed by real failure modes of RC walls after earthquakes. Design codes and standards based on the knowledge of the failure modes of the reinforced concrete walls were developed in order to obtain the ductile failure mechanisms. A special case is the failure mode of the reinforced concrete shear walls with vertical staggered openings. If at coupled walls the elements must be designed so that the plastic hinges appear at the ends of the coupled beams and then in the pier, this thing is more difficult at shear walls with staggered openings. Theoretical and experimental studies on structural walls with staggered openings, lamellar walls and walls with bulbs at the end have been made recently. There have also been studied the followings: the degradation of the stiffness, the ductility function to the intensity of the seismic force, the presence of the vertical forces, the position and the size of the openings and the reinforcing ways. The article presents the results of the theoretical and experimental tests on failure modes of three types of reinforced concrete shear walls with staggered openings which are compared to those obtained from walls with vertical ordered openings as far as the seismic response is concerned. The failure modes of the structural walls under seismic stress have been identified using calculus programs and cyclic alternated experimental tests. The theoretical research on the failure modes was the basis for the elaboration of a simplified methodology for the calculus of the maximum theoretical seismic force that produces the concrete crushing in the ultimate limit stage. The results theoretically obtained with the help of the calculus programs have been confirmed experimentally. The analysis of the failure modes, obtained with the computing methodology proposed, contributed to the completion of the seismic design codes for shear walls with staggered openings. منبع عملکرد_دیوارهای_برشی_بتنی_با_بازشوهای.pdf
Behaviour of thin steel plate shear walls regarding frame members M.M. Alinia∗, M. Dastfan Department of Civil Engineering, Amirkabir University of Technology, Tehran, Iran Received 31 January 2005; accepted 2 November 2005 Abstract Steel plate shear walls in buildings are known to be an effective and strong means for resisting lateral forces. The view of some structural designers is to use heavy stiffeners to reinforce and increase the buckling capacity of shear walls; whereas, if the walls are left unstiffened and allowed to buckle, their energy absorption will increase significantly due to the post-buckling capacity. On the other hand, the optimal design of thin steel plate shear walls (TSPSWs), which are categorized as thin-walled structures, involves the proper prediction of their buckling strength. In turn, this prediction is a function of the status of their assumed boundary conditions. Many design rules conservatively suggest simply supported boundary conditions for elastic member restraints. In this paper, the effects of surrounding members (i.e. beams and columns) on the overall behaviour of TSPSWs are studied. The results show that, unlike the present view, the flexural stiffness of surrounding members has no significant effects, either on elastic shear buckling or on the post-buckling behaviour of shear walls. The torsional rigidity has a significant effect only on the elastic buckling load, and the extensional stiffness slightly affects the post-buckling capacity. c 2005 Elsevier Ltd. All rights reserved. Keywords: Shear buckling; Thin plates; Elastic boundary conditions; Shear walls; Plate girders; Post-buckling Journal of Constructional Steel Research 62 (2006) 730–738 1-s2.0-S0143974X05001835-main.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