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

摘要

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 earthquakeresilience. 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.