Finite element simulation and strength evaluation on innovative and traditional composite shear wall systems

Abstract

SummaryComposite shear wall (CSW) system, which consists of a steel boundary frame and a steel panel with a reinforced concrete (RC) panel attached to one side of it using bolts, is commonly used in mid‐ to high‐rise buildings. In a CSW system, RC panel functions as out‐of‐plane restraint to prevent overall buckling of steel panel, thereby enhancing system behavior. However, for a traditional CSW system, the RC panel is in direct contact with the steel boundary frame. The RC panel tends to crush under seismic loading, thereby leading to a weak constraint to steel panel buckling. The innovative CSW system, where a gap remained between steel boundary frame and RC panel, demonstrated better cyclic behavior than the traditional CSW system. Current studies aimed to investigate cyclic behavior, parameter effects, and determination of RC panel stiffness of CSW systems. In this paper, detailed FE models were developed for simulating cyclic behavior of both innovative and traditional CSW systems and validated by test results. FE models accurately predicted lateral load‐drift response and failure patterns of both innovative and traditional CSW systems. System failure patterns and load‐carrying mechanism of RC panels were discussed. The effects of major parameters, including steel panel thickness, RC panel thickness, ratio of bolt spacing to steel panel thickness, and gap between frame and RC panel, were examined using the validated models. Simulation results indicated that steel panel thickness contributed to increase the lateral strength and initial stiffness of both innovative and traditional CSW systems. Although RC panel thickness, ratio of bolt spacing to steel panel thickness, and gap between frame and RC panel had negligible effects on system strength and stiffness, they should also be carefully designed to ensure local stability of the steel panel and system ductility. Formulations were proposed for predicting the lateral strength of both innovative and traditional CSW systems. The average difference between calculated and test/simulated lateral strength was less than 3%.