SEISMIC RESPONSE OF EXISTING RC BUILDING UNDER REVISED SEISMIC ZONE CLASSIFICATION USING PUSHOVER ANALYSIS

Existing Reinforced Concrete (RC) buildings constructed before two decades typically have the design details which are considered to be highly inadequate under the present revised seismic code of practice. Many of these structures have suffered significant structural damage during recent earthquakes. Significant research effort has been devoted to the development of behavioral models and modeling techniques to predict the behavior of these buildings. However there are no models that have been shown to predict observed response with a high level of accuracy and precision. In this paper, a seven storey RC building is considered to investigate the structural seismic response. This RC building is analysed and designed for the gravity and lateral loads using the codal provisions followed a decade ago (previous version of the code). Then the designed structure is evaluated for the seismic performance under the old and the revised code of practice using Pushover Analysis. The Displacement controlled Pushover Analysis was carried out and the Pushover Curve was obtained for the building in both X and Y directions. The Capacity Spectrum, Demand Spectrum and Performance point of the building, under old and the revised seismic zone classification was found in both the direction using the analysis carried out in SAP 2000. From the analysis it is understood that, the frame is capable of withstanding the presumed seismic force with some significant yielding at several beams. The results obtained in terms of demand, capacity and plastic hinges gave an insight into the real behaviour of structure.