Resilient Seismic Behavior of Self-centering Y-eccentrically Braced RCS Frames

To develop a high-performance resilient structural system enabling rapid post-earthquake functional recovery in seismic-prone regions, this study systematically investigates the seismic performance and damage characteristics of a novel self-centering resilient prefabricated Reinforced Concrete Column-Steel Beam (RCS) Y-eccentrically braced frame, hereafter referred to as RP-RCS-YEBF. First, the detailed configuration of the proposed RP-RCS-YEBF is presented, and a refined finite element (FE) model is established using the OpenSees numerical platform. The accuracy of the FE model in simulating the hysteretic behavior and residual deformation of the frame is fully validated against quasi-static test results. Two self-centering joint arrangement schemes (RP-RCS-YEBF-1 and RP-RCS-YEBF-2) are designed, and their seismic performance is compared with that of a conventional RCS structure through systematic numerical analyses, including nonlinear static analysis, dynamic time-history analysis, and seismic vulnerability analysis based on the multiple stripe analysis (MSA) method. Results show that both proposed schemes exhibit higher ductility than the conventional RCS structure; their peak and residual story drifts under four-level seismic fortification objectives can well meet the preset performance requirements, significantly outperforming the conventional RCS structure. Specifically, RP-RCS-YEBF-1 demonstrates superior collapse resistance, while RP-RCS-YEBF-2 excels in self-centering capacity, seismic damage control, and post-earthquake repairability. This study confirms that the proposed RP-RCS-YEBF is an advanced resilient structural system integrating excellent seismic performance and recoverable functionality, which can provide a solid theoretical basis for relevant engineering design and practical applications.