Damage Assessment of RC Frame Structures under Long Duration Aftershock Ground Motions

摘要

This study quantifies the influence of strong ground motion duration (SGMD) of aftershocks on the cumulative damage caused to a RC frame structure. Understanding the effect of ground motion duration on cumulative damage and failure mechanisms will bring us one step closer to preventing future earthquake-induced collapses and can also aid in improving Building code. In order to study the effects of Duration, the other time-frequency characteristics i.e. amplitude and frequency content are kept similar. A realistic nonlinear numerical structure is modelled in SAP2000 in order to incorporate cyclic deterioration of strength and stiffness. Two sets of data are considered i.e. longer duration (40sec) and shorter duration (25 sec) and for each set of data cumulative damage are calculated using modified Park and Ang Damage Index. It is seen that in general longer duration data sequence causes more damage than shorter duration sequences because of longer cycles of loading.