Seismic liquefaction hazard-vulnerability analysis and mapping of existing important buildings of Mumbai city, India

Abstract

The predominantly saturated sandy soils of 2m to 3m thick in Mumbai city of India are likely to be subjected to seismic liquefaction during moderate to high earthquake magnitudes (Mw) of greater than 6.5. In this paper, seismic liquefaction hazardvulnerability-risk analysis and mapping of existing important buildings of Mumbai city such as schools, hospitals, Government offices, hotels, fire stations, heritage structures, and educational institutions are carried out in ArcGIS platform. The seismic liquefaction of the sandy soils of Mumbai city is estimated in terms of probability (PL) of failure and the vulnerability is assessed as Overall building Vulnerability Index (VIo). One square kilometer grid based estimated PL and VIo are computed for the entire Mumbai city, and are combined for preparing liquefaction risk maps for Mumbai city for different earthquake magnitudes (Mw). The liquefaction risk maps show that some of the areas of Mumbai city lie in moderate to severe liquefaction zones having risk value ranging between 0.5 and 1.0. These risk maps can be helpful to predict the extent of damage caused to the existing important buildings due to liquefaction, to take action against prevention of liquefaction hazard, and for planning rescue and recovery operations during earthquake hazard.