Liquefaction Triggering Criterion Using Shake Table Test

Earthquake induced liquefaction in saturated granular soils is an important phenomenon causing severe damages. In order to minimize the ill-effects due to liquefaction, various lab tests, field tests are being used which assess the liquefaction potential. In the present study the shake table test has been used for assessing soil liquefaction of loose saturated cohesionless sand by simulating earthquake conditions in the laboratory. The tests are conducted on shake table apparatus, with the varying range of relative density and maximum acceleration. This paper deals with the experimental investigations carried out to establish an unique criterion for initiation of liquefaction for shake table test, which best delineate with the initialization of liquefaction in clean uniform sand. It is observed that for the clean sand tested in shake table test liquefaction is observed to trigger at pore pressure ratios even less than or equal to one for loose and medium state of soil up to maximum shaking of 0.32g.For higher magnitude of shaking and for denser soils initiation of liquefaction is observed to take place for pore pressure ratios greater than one. Few tests are based on the field data where actual field parameters are used to prepare laboratory soil model and is observed that the criterion of the occurrence of liquefaction in the laboratory shake table model is in close agreement with actual field data.