Historically large earthquakes throughout the world show that the liquefaction related ground failure commonly causes extensive structural and lifeline damage in cities. The seismic behaviour of a saturated soil depends on the potential for significant strains or strength loss that can contribute to ground deformations or instability during an earthquake. Detailed assessment of liquefaction hazard is important for evaluating and reducing the risk through appropriate mitigation techniques. In this paper simplified methods given by Seed and Idriss and as amended by various researchers from time to time has been used for liquefaction hazard assessment of two cities, Vijayawada and Mumbai which fall in seismic zone III of moderate seismic risk. The factor of safety against liquefaction has been calculated using average SPT ‘N’ value collected from different borehole data at several locations in the Vijayawada city. Liquefaction susceptibility analysis based on the average SPT ‘N’ value shows that depth of Liquefaction lies between 2.50 to 2.95m. Seismic soil liquefaction is evaluated for Mumbai city in terms of the factors of safety against liquefaction along the depths of soil profiles using standard penetration test (SPT) based simplified empirical procedure. As the majority of the sites in the city are of reclaimed land, the vulnerability of liquefaction is observed to be very high.
