Liquefaction hazard scenario of Imphal city for 1869 cachar and a hypothetical earthquake

In the present article liquefaction potential of Imphal city is reported in the form of two indices, i.e., LPI (Liquefaction Potential Index) and LSI (Liquefaction Severity Index), for 1869 Cachar earthquake (Mw 7.5) along the Kopili fault and probable future great earthquake (Mw 8.1) in the Indo-Burma subduction zone. The Factor of Safety (FS) against liquefaction has been computed by using modified procedure given by Idriss and Boulanger (2006) for all depths of 122 boreholes. The computed FS have been used as input parameters for evaluating LPI and LSI indices for Imphal City. Based on these LPI and LSI indices, liquefaction potential hazard contour maps of Imphal city is prepared. It is observed that over a large area of Imphal city is highly vulnerable to liquefaction failure in the events of the selected earthquake. The liquefaction hazard obtained at each site exhibits a good agreement with the damages documented for 1869 Cachar earthquake. This contour map can be served as a guideline for engineer and planner in site selection for upcoming projects and helps city administration in mitigating the city from future hazards. Copyright © 2012, IGI Global.