Seismic design and evaluation of self-centering coupled wall systems using equivalent energy design procedure

Self-Centering Coupled Wall (SCCW) system is an innovative seismic force-resisting system designed for high-rise applications. SCCW is similar to the conventional reinforced concrete coupled wall (RCCW) system with the following two exceptions: 1) the SCCW replaces the reinforced concrete coupling beams with the steel self-centering conical friction dampers (SCFDs); 2) the base of the SCCW is equipped with the steel rocking base dampers (RBDs) which is designed to rock during earthquake shaking. SCCW system dissipates the earthquake energy mainly through SCFDs and RBDs instead of yielding in the reinforced concrete coupling beams and the wall base. Since the SCCW and RBDs are specially designed to dissipate the earthquake energy through a stable and damage-free mechanism, the SCCW is expected to be damage-free after a strong earthquake shaking. More importantly, SCCW is designed to re-center after the shaking, making this system more resilient for applications in high seismicity regions. In this study, the equivalent energy design procedure (EEDP) developed for fused structural systems is adopted to ensure that the SCCW system can achieve high performance under different levels of ground shaking intensities. For this purpose, three prototype buildings with different heights (15-story, 25-story, and 35-story) located in Vancouver, British Columbia, Canada, are designed using EEDP. Detailed finite element models of the prototypes are developed using OpenSees and are subjected to a series of nonlinear time history analyses. The analysis results indicate that the SSCW system, designed using the EEDP, performs well under different levels of earthquake shaking intensities. Hence, this system can be used as an effective seismic force-resisting system for high-rise applications.