Influence of the rubber end plate on the hysteretic performance of SC-BRBs and structural seismic design

Abstract

Abstract Existing self-centering braces are easily affected by machining errors, and the initial stiffness of the braces will obviously be less than the theoretical value, which is unfavourable for the seismic design and dynamic response control of the structure. Based on a theoretical analysis, the idea of using a rubber end plate to reduce the influence of machining errors is proposed in this paper, and the configuration of a self-centering buckling-restrained brace with rubber end plates (SC-BRB-REP) is formed. The quasi-static test shows that the SC-BRB-REP can not only effectively control the residual deformation but also substantially improve the ability to control the initial stiffness of the brace, and the difference between the actual initial stiffness and the theoretical initial stiffness is less than 8%. The seismic design process of the SC-BRB frame is established based on the concept of direct displacement-based design (DDBD). Through the hysteretic behaviour research of the brace and the dynamic time-history analysis of the structure, it is evident that the reduction in the initial stiffness of the brace will lead to the reduction in the bearing capacity, thus increasing the seismic response of the structure and even exceeding the expected design objective. The SC-BRB-REP improves the ability to control the initial stiffness, and its structural design parameters and actual seismic response are basically consistent with the expectations, which effectively improves the structural design accuracy.