Seismic response of steel-plate concrete composite shear wall piers

Steel-plate concrete composite (SC) walls are being used in safety-related nuclear structures, and have been implemented in buildings for non-seismic applications. These walls comprise two steel faceplates, infill concrete and connectors. The connectors join the steel faceplates to each other and to the infill concrete. There is a limited body of knowledge on the inelastic seismic behavior of SC walls.;This research project focuses on the seismic response of SC wall piers: walls without boundary columns or flanges. Experimental and numerical simulations were performed to build a body of data that will enable others to develop design guidance and predictive equations. The experiments on four rectangular SC wall piers were conducted in the NEES laboratory at the University at Buffalo. Each wall had an aspect ratio of 1.0 and their cyclic responses were affected by both flexure and shear. The walls were constructed with a bolted baseplate and tested using a reusable foundation block. High force-capacity actuators imposed lateral displacements on the walls to simulate seismic loading effects. The damage to the walls progressed similarly with increasing story drift: infill concrete cracking, faceplate yielding and buckling, infill concrete crushing and spalling, and steel faceplate fracture. Faceplate slenderness in the ratio considered (21 to 32) affected post-peak-strength response but not peak shearing force. The flexibility of the baseplate connection contributed substantially to the drift response of the walls.;Finite element models of the SC walls were developed in ABAQUS and validated using the test data. The effects of foundation connectivity, infill concrete and faceplate slenderness ratio on the response of SC wall piers were investigated.;A parametric study on the in-plane monotonic response of SC wall piers was performed using factorial experimentation to provide insight into the relationship between design parameters and peak shearing force. The validated ABAQUS model was used for the numerical experiments. The six parameters considered were wall aspect ratio, total wall thickness, faceplate reinforcement and slenderness ratios, faceplate yield stress and concrete compressive strength. Of the six parameters, the steel faceplate reinforcement ratio is the most important over the ranges considered for the parameters.