Residual displacement responses of structures subjected to near-fault pulse-like ground motions

The residual deformation is one crucial factor determining the structural safety and the structural repair cost after earthquakes. Hence, the quantitative estimation of residual displacements is necessary for modern performance-based design and assessment procedures. This study evaluates the residual displacement responses of single degree of freedom (SDOF) systems with Bouc-Wen model under near-fault pulse-like ground motions through nonlinear dynamic analyses. To this end, four quantitative indexes for the residual displacement responses are first defined and calculated. The dispersion of the four quantitative indexes is then analyzed, and the correlations between the residual displacement and the yield displacement, maximum inelastic displacement or elastic displacement are also investigated. The analysis results indicate that using the maximum inelastic displacement can better estimate the residual displacement of structures under near-fault pulse-like ground motions. Furthermore, the influences of the structural properties and ground motion characteristics on the ratio of the residual displacement to the maximum inelastic displacement (Cr) are analyzed statistically. Finally, a simplified equation for predicting this ratio is regressed to estimate residual displacements of structures under near-fault pulse-like ground motions.