Large-Scale Experimental Study of Ring Shaped–Steel Plate Shear Walls

Abstract

The ring shaped–steel plate shear wall (RS-SPSW) is a new lateral load resisting system that offers improved seismic energy dissipation and stiffness over conventional steel plate shear wall systems. Thicker web plates with specially designed cut-outs leaving connected ring shapes make the RS-SPSW less susceptible to buckling. The RS-SPSW concept was investigated through large-scale experiments on five, two-thirds scale specimens. The specimens were designed with varying strength to represent demands at the first and fifth floors of a 6-story building and varying ring geometries to capture different limit states such as plastic yielding of the ring, shear buckling of the panel, and lateral torsional buckling of the rings. The large-scale experiments validated the ability of the RS-SPSW concept to delay buckling, which resulted in fuller hysteretic behavior and 7% more energy dissipation per cycle at 2% story drift than a conventional steel plate shear wall with the same strength. An equation for plastic shear strength was developed and shown to accurately predict the yield strength of RS-SPSWs specimens with 1.4% error on average. Lastly, the experiments revealed a mode of behavior wherein inelastic deformations can concentrate in outer rows of rings leading to increased deformation demands in these rows. An idealized model of the deformation mode is presented along with equations to predict the maximum deformation demand for any ring in the panel.