Effect of past history on liquefaction resistance of level ground in shaking table test

Abstract

In recent years, many researchers have discovered that using relative density as a single index parameter, cannot be correlated well with liquefaction resistance. In general, it is also governed by past-liquefaction history. To study the effect of liquefaction history on liquefaction resistance of level ground in more detail, a series of shaking table tests was performed on loose and dense silica sand models. Small base acceleration was implemented on loose models and then increased up to 1000 gal. Ground motion, behaviour and relative density change during each liquefaction stage were monitored. The results showed that liquefaction history can greatly affect future liquefaction resistance. After being subjected to repeated liquefaction, loose sand models stopped liquefying at 1000 gal with a relative density of approximately 80%, regardless of the initial acceleration. However, the dense sand model with initial relative density of 80% subjected to the initial acceleration of 700 gal continuously liquefied until reaching a relative density of nearly 100% at 1000 gal.