Hysteretic model and seismic performance of a self-centering brace equipped with energy absorbing steel plate clusters

Abstract

The use of self-centering (SC) devices has been recognized as a promising strategy to improve the seismic resilience of structures, owing to their capacities for SC and energy dissipation (ED). This paper presents a comprehensive study on a SC brace (SCB) equipped with energy absorbing steel plate (EASP) clusters. Firstly, the configuration and deformation mode of the SCB were described. Then, a hysteretic model of the SCB was proposed based on the Bouc-Wen model, and the behavior of the SCB was described in detail. The accuracy of the hysteretic model was subsequently verified by experimental results. On the basis of this, the theoretical analysis was carried out to evaluate the effect of the design parameters on the hysteresis performance of the SCB. The results show that the ratio between the activation force of the SC system and the yield force of the ED system (ρ) has a significant impact on the hysteresis performance of the SCB. As the value of ρ increases, the SC capability of the SCB increases, but the ED capacity decreases. Finally, the seismic performance of the steel frame which adopts the SCB was evaluated using nonlinear response history analysis. The results indicate that the SCB with a ρ value of 1.0 can achieve a comparable structural deformation response with a buckling restrained braced (BRB) frame, and the residual drift of the SCB frame is less than 0.2% under ground motions of varying hazard levels.