THE EFFECT OF MAINSHOCK-AFTERSHOCK IN SUCCESSIVE EARTHQUAKE ON THE RESPONSE OF RC BUILDING

This study investigated the seismic behavior of a G+8 storey building subjected to mainshock–aftershock sequences using time-history analysis. A comparative assessment was carried out between bare and infill frames, as well as between horizontal and vertical earthquake components.   Key conclusions:  Buildings experience significant damage during the mainshock, and subsequent aftershocks further increase the level of damage.   Infill frames exhibit greater damage than bare frames under both mainshock and aftershock conditions, indicating lower seismic performance.   Horizontal earthquake components cause substantially more damage than vertical components.   Compared to the mainshock, aftershocks increase damage probabilities in the slight, medium, extensive, and collapse states by 11.37%, 9.50%, 1.98%, and 0.34%, respectively.   Infill frames show considerably higher damage than bare frames in all damage states during both mainshock and aftershock events.   Horizontal components result in higher slight and medium damage, whereas vertical components show slightly higher extensive and collapse damage due to marginally greater spectral displacement.

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