Need for Pre-Earthquake Risk Assessment of Buildings in Moderate-to-Severe Earthquake Prone Areas in India

Abstract

Due to rapid urbanization of Indian cities in last few decades, there is a tremendous pressure on housing industry to cater to the needs. This fast pace of construction activity with no planning has led to the growth of medium to highrise buildings,causing serious threat to life and property. The same is clearly evident from the losses during earthquakes in the recent past including twin major earthquakes in Nepal. Hence there is a need to understand the earthquake risk and take corrective measures. Seismic risk assessment has three components viz., Hazard, Exposure and Vulnerability. Vulnerability assessment of buildings consists of following three stages viz., 1) Rapid Visual Survey (RVS), 2) Preliminary Assessment and 3) Detailed Assessment. Following the above three stages, on a sample of around 10,000 buildings, graphs have been developed to assess the damage of buildings in cities prone to earthquake hazard. These graphs can be used to perform pre-earthquake exercise. Graph will indicate the type of damage a building will have when subjected to a particular level of shaking which depends on the magnitude of an earthquake. The information on level of shaking will come from seismological inputs. These graphs are being tested in different areas to validate the study in future earthquakes.