PRELIMINARY LIQUEFACTION POTENTIAL ANALYSIS OF VIJAYAWADA REGION

Abstract

Experience from past earthquakes has demonstrated the vulnerability of structures to seismically induced ground deformation. During earthquake, soil can fail due to liquefaction with devastating effect such as landslides, lateral spreading, or large ground settlement. The phenomenon of liquefaction of soil had been observed for many years, but was brought to the attention of engineers after Niigata (1964) Alaska earthquakes (1964). Liquefaction is a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading. Liquefaction and related phenomena have been responsible for tremendous amounts of damage in historical earthquakes around the world (Borcherdt R.D 1991; Dobry R, 1981). During the Bhuj earthquake, India on 26th January 2001 (M=7.7) lot of damages had been occurred due to liquefaction and other ground failures (Rao and Mohanty, 2001). In this paper, a preliminary liquefaction hazard assessment was carried out using the available SPT data. From these investigations it was observed that a vast majority of liquefaction occurrences were associated with sandy soils and silty clays of low plasticity.