SSI Effects on Constant-Ductility Inelastic Displacement Ratio and Residual Displacement of Self-Centering Systems Under Pulse-Type Ground Motions

This study aims to examine the seismic response of self-centering single-degree-of-freedom (SDOF) systems exhibiting flag-shaped hysteretic behavior, while considering soil–structure interaction, in contrast to prior research that predominantly addressed conventional hysteretic behavior and overlooked soil flexibility. The inelastic displacement ratio, residual displacement, and residual displacement ratio are used to analyze the seismic response of interacting structures. These structural response parameters are calculated based on the nonlinear dynamic analyses of SDOF systems subjected to 56 near-fault pulse-type ground motions. Analyses are conducted for varying values of ductility, energy dissipation coefficient, strain hardening ratio, aspect ratio, structural period, and normalized vibration period by pulse period of the record. New formulas to estimate the inelastic displacement ratio and residual displacement of self-centering SDOF systems with soil–structure interaction are developed based on a statistical analysis of the findings.