A Case Study on Vulnerability Risk Assessment of Buildings in Chennai Using Rapid Visual Screening

Abstract

India is witnessing drastic urbanization and economic growth which in turn helps in building its infrastructure rapidly. A large amount of construction of multistorey buildings has been done in many metropolitan cities, where one such city is Chennai, Tamil Nadu. In the recent scenario, being an unplanned and most densely populated city, there is a chance of an increase in threats to several natural hazards viz, earthquake, fire etc.This shifts our focus in understanding the risk associated with these hazards to ensure the safety of the structures. Many studies have been carried out to estimate the risk of the structure but are proven to be quite cumbersome. To counterpart, such complex methods, a simple approach namely Rapid Visual Screening (RVS) Method is used which is proven to be simple and reliable. Rapid visual screening has been widely used but the application of this method in India is limited. The present study helps in identifying the seismic risk associated with an area of interest in Chennai (Mylapore, Santhome, Triplicane) and elaborates its usability for other metropolitan cities. A total of 100 buildings of different housing typologies have been studied and its RVS score is calculated based on various building parameters. The pushover analysis is done for selected 5 buildings based on obtained RVS score and the results are used for further investigation. The RVS scores were correlated with the damage state curves and it is observed that buildings with RVS score greater than 120 are known to have no damage for a design earthquake with peak ground acceleration of 0.16g.Finally, the risk assessment in terms of building damages during an earthquake is correlated based on its RVS score and push over curve.