Abstract:
The assessment of liquefaction potential is one of the important scientific
problems for the geotechnical investigators. Liquefaction of loose saturated cohesion less soil during earthquake has been a major cause of damage due to earthquake for the
buildings, earth embankments and other civil engineering structures. The study area
of the coastal stretch of Kollam in western Kerala, India, mainly consists of coastal
alluvial deposits and marine sand. Samples were collected along the length and width
of coastal stretch of Kollam and are tested to obtain water content, dry density, fines
content and the gradation curves. Limiting curves-based gradation criteria proposed
by Tsuchida (1970) and empirical relation for stress ratio (SR) values obtained by
Chien et al. (2002) were used for the calculation of liquefaction potential at sample
locations. Spatial analysis of this data is done using QGIS to delineate the region into
most liquefiable, liquefiable, less likely to be liquefiable and not liquefiable zones.
The susceptibility map developed based on SR criteria is found to be in agreement
with the liquefaction potential map developed by overlay of the two criteria which
infer the dominant influence of dry density of the deposits of Kollam coastal stretch.
Further, a ground truth examination of the final susceptibility map revealed that the
zones in which water table lies within 0–5 m from ground level are more vulnerable
to liquefaction in the Kollam coastal stretch. The proposed liquefaction susceptibility
map can be used as a firsthand info on liquefaction potential of region which can aid
in site-specific studies for future development
