Mechanical behaviour of SPSWs with a central opening reinforced by CFS members

Abstract

It is often necessary to set up doors, windows, or equipment plumbing openings on the steel plate shear walls (SPSWs) to meet the functional requirements of the building. Meanwhile, to reduce the weakening of the mechanical performance of SPSWs caused by openings, it is usually necessary to weld stiffeners around the openings. However, welded stiffeners often bring residual stress and deformation to the structures. Therefore, the prefabricated stiffeners for opening reinforcement, cold-formed steel (CFS) members, were proposed in this study. To investigate the mechanical performance of SPSWs with a central opening reinforced by CFS members, the quasi-static test was carried out, and the failure mode and hysteresis curve were examined. Besides, compared with the SPSW that was the same size and without openings, the effects of openings on the lateral strength, energy dissipation capacity, and stiffness degradation were analysed. Based on the finite element (FE) model verified by the experiment results, the influences of the arrangements of the CFS members, the opening size, and the width-to-height ratio of the opening were analysed. Finally, according to the reinforcement mechanism of CFS members around openings, a simplified analysis model (SAM) was proposed. In SAM, SPSW with openings reinforced by CFS members can be equivalent to the SPSW without openings, which helps to simplify the calculation greatly. The results showed that the SAM proposed in this study had high calculation accuracy when compared with the experiment results and the FE results.