Seismic Vulnerability Assessment of Existing Rc Buildings in Gis Environment

With rapid population growth over the past 30 years and no significance seismic activity during this period, the unchecked development of the built environment in Bangladesh has been resulted in little resilience to earthquake. Identifying buildings due to this unchecked development that has high vulnerability is of critical importance both for reliable loss estimation as a result of an expected earthquake and setting priority criteria for strengthening of those buildings. In this study, using GIS-Detailed Area Plan (DAP) of Chittagong Development Authority (CDA), rapid individual building assessment based on statistical method as demonstrated in Istanbul, Turkey has been considered to evaluate seismic vulnerability of reinforced concrete buildings. Number of stories above the ground level, soft story index, pounding effect, topographic effect, existing of short columns, apparent building quality, local soil conditions, overhang ratio, minimum normalized lateral stiffness index, minimum normalized lateral strength index and normalized redundancy score are selected as the basic estimation variables. In this method, the discriminant scores obtained from two discriminant functions are combined in an optimal way to classify existing buildings as “safe”, “unsafe” and “requires detailed evaluation”. This paper presents seismic vulnerability assessment application in GIS environment on a City Ward entitled as “Purbo Madarbari” of Chittagong, the port city of Bangladesh.