Probabilistic IM-Based Assessment of Critical Engineering Demand Parameters to Control the Seismic Structural Pounding Consequences in Multistory RC Buildings

This research aims to assess and quantify the significance of incorporating the seismic performance of global and local engineering demand parameters (EDPs) within probabilistic frameworks when structural pounding of adjacent buildings occurs. For this purpose, the seismic performance of six-story and twelve-story reinforced concrete (RC) frames subjected to floor–floor pounding is assessed. The pounding is caused by an adjacent shorter and stiffer structure with the top contact point at the middle of the tall building’s total height. Displacement-based and ductility-based EDPs are evaluated at different performance levels (PLs) and at different separation distances (dg). The seismic performance of the RC frames without considering pounding is also evaluated. Incremental dynamic analyses (IDAs) are performed, and probabilistic seismic demand models (PSDMs) are developed to establish the fragility curves of the examined RC frames. The probability of earthquake-induced pounding between adjacent structures is properly involved with the median value of Sa,T1 that corresponds to an acceptable capacity level (acceptable PL) of an EDP. The results of this study indicate that excluding structural pounding consequences from the probabilistic frameworks related to the seismic risk of colliding buildings leads to unsafe seismic assessment or design provisions.