Cyclic behaviour of unstiffened steel plate shear walls.

摘要

Unstiffened steel plate shear walls (SPSWs) are effective and economical lateral load resisting system, especially in regions of severe earthquakes. The system consists of columns intersected at the floor levels by beams and steel infill plates connected to its boundary members over the full height of the frame bay. Despite the recent research progress on this system and the attention from the structural engineering community, to date, relatively few structures that use this system have been constructed in North America. The lack of a reliable and effective analytical tool is likely one of the barriers for wide application of this system. Until now, the finite element analysis of SPSWs has been implemented with only limited success.; A large-scale three-storey SPSW was tested under a combination of constant gravity load and cyclic lateral loads in a quasi-static condition in order to increase the database of test results and monitor closely the behaviour of the boundary members. Twenty-four cycles of loading were applied to the test specimen, of which 14 cycles were in the inelastic range. Characteristic pinching of hysteresis loops was observed in the inelastic range. The specimen showed high initial stiffness, excellent ductility and energy absorption capacity, and stable hysteresis loops. Although one of the beam-to-column moment connections ruptured during the test, this rupture did not detrimentally affect the strength and behaviour of the specimen.; A finite element model based on nonlinear dynamic explicit formulation was developed. A kinematic hardening material model subroutine was implemented to simulate the Bauschinger effect and a special loading frame was developed to implement a displacement control analysis. The effectiveness and validity of the model was demonstrated by comparing its monotonic and cyclic predictions with the results of tests conducted on a four storey and the three storey SPSW tested in this research.; A set of ten scale independent non-dimensional parameters that affect the behaviour of a SPSW panel under shear and gravity load was identified. Effect of some of the main parameters on the stiffness and capacity of SPSWs were investigated. It was concluded that column flexibility parameter has a significant effect on the behaviour of SPSWs. A method for considering the effect of overturning moment was proposed.