Numerical simulation of liquefaction-induced deformation of embankments on non-homogeneous foundation

摘要

In this study, numerical analyses have been performed for a sandy embankment lying on lique-fiable non-homogeneous soil using finite element code based on extended subloading surface model (Takahashi 2002). Non-homogeneous soil deposit comprises of Toyoura sand and periodically distributed patches of less permeable layer of silty sand. Analyses were also conducted for embankments on uniform sand comprising of only Toyoura sand. It was found that excess pore water pressure (EPWP) ratio values were higher below the embankment and free field region at shallow depths in non-homogeneous foundation during shaking, manifesting large amount of crest settlement and lateral deformation of embankment. In addition, dissipation of pore water took a longer period of time, which might be incorporated by migration of pore water from underlying foundation soil toward the free field, causing an additional larger settlement of embankment and larger heave at the free field ground surface and post-liquefaction delayed failures in non-homogeneous foundation.