Rapid assessment for seismic vulnerability of low and medium rise infilled RC frame buildings

Abstract

An indexing method for rapid evaluation of the seismic vulnerability of infilled RC frame buildings in Jordan is proposed. The method aims at identifying low and medium rise residential buildings as safe or in need of further detailed evaluation. Following a rapid visual screening, the building is assigned a Basic Capacity Index (BCI); five performance modifiers are identified and multiplied by the BCI to arrive at the Capacity Index (CI) of the building. A Capacity Index lower than a limit CI value indicates that the screened building could experience moderate earthquake damage whereas a higher value implies that minor damage, if any, would take place. To establish the basic evaluation parameters; forty RC frame buildings were selected, designed and analyzed using static nonlinear analysis and incorporating the effect of infill walls. Effects of seismicity, local site conditions, horizontal irregularities (setbacks and re-entrant corners), vertical irregularities (soft story at ground floor level) and overhangs on the seismic performance of local buildings were examined. Assessment forms were designed and used to evaluate and rank 112 sample buildings. About 40% of the surveyed buildings were found to be in need of detailed evaluation to better define their seismic vulnerabilities.