Seismic performance assessment of three-layer ring spring-type self-centering reinforced concrete building frames: Insights into the bearing action behavior

The stiffness of pre-compression type self-centering dampers increases sharply when they reach their ultimate deformation capacity, denoted as the bearing action behavior. However, the impact of this behavior on seismic and collapse performance has not been extensively explored. To this end, this study provides insight into the seismic and collapse performance of reinforced concrete (RC) frames with different dampers (i.e., the ring spring-based self-centering damper (RSD) and the three-layer ring spring-based self-centering damper (TRSD)) regarding their ultimate deformation capacity. Firstly, the configuration and working mechanism of the recently proposed TRSD are elucidated, followed by the introduction of the concept of bearing action behavior. Then, nonlinear and incremental dynamic analyses are conducted on the 6-story RC frames equipped with the RSD and TRSD to illustrate the significance of considering bearing action behavior in seismic performance evaluation. Next, the effectiveness of two strategies (i.e., increasing the number and outer diameter of springs for the RSD) for reducing the influence of the above-mentioned behavior on the seismic and collapse performance is quantitatively evaluated. The results reveal that the bearing action behavior of the RSD and TRSD significantly influences the seismic response and collapse mode, especially under high seismic hazard levels, and therefore should be considered to obtain an accurate seismic performance evaluation. The TRSD with higher loading resistance and stronger energy dissipation capacities will provide satisfactory seismic response mitigation, delaying the adverse influence of the above-mentioned behavior and reducing the number of springs and outer diameter demands by 46.67 % and 77.05 %.