PROBABILISTIC SEISMIC ASSESSMENT OF RESIDUAL DRIFT DEMANDS IN EXISTING BUILDINGS

摘要

This paper presents a probabilistic approach to estimate residual drift demands (e.g. residual roof, residual drift at specific stories, and maximum residual drift over all stories) during the seismic performance-based assessment of existing multi-story buildings. The suggested approach combines residual drift demand fragility curves with very recently introduced maximum inelastic displacement seismic hazard curves to obtain sitebuilding- specific residual drift demand hazard curves which express the mean annual frequency of exceeding residual drift demands. In particular, functional models that capture the variation of central tendency and dispersion of residual drift demands with changes in the ground motion intensity are proposed. It is shown that the proposed procedure can be very helpful during the performance-based seismic assessment of existing multistory building frames since it incorporates explicitly the epistemic uncertainty (i.e. record-to-record variability) inherent in the estimation of residual drift demands at the end of the seismic excitation