Hysteresis behavior of bottom-story self-centering shear wall with steel brace-assembled bottom

Abstract A self-centering shear wall (SC-SW) with a steel brace-assembled bottom is proposed to avoid the residual drift of reinforced concrete shear walls (RCSWs) due to damage in corners and achieve an adequate earthquake-resilience. The residual displacement of traditional RCSW is caused by the bending and shear deformations of the plastic hinge and the deformation of the upper plate, as is confirmed by a cyclic loading test on a typical RCSW specimen. A steel brace-assembled bottom consisting of a steel V-shaped connecting beam, a bearing, and two self-centering braces is designed to control the residual deformation of the RCSW plastic hinge zone. The simplified equations governing the skeleton curve of the SC-SW are derived. An RCSW and SC-SW with the same initial stiffness and ultimate bearing capacity are simulated and compared via the experimentally validated finite element model. The results indicate that the SC-SW exhibits a flag-shaped hysteresis response with an excellent self-centering capability. The maximum residual story drift ratio is less than 0.125%. The skeleton curve equations agree well with the measured data of the analytical specimen. The overall performance of the SC-SW is primarily affected by the braces. The energy dissipation capability of the SC-SW remains insufficient due to the lesser development of plastic deformation.