Numerical modeling of liquefaction-induced lateral spreading

ABSTRACT: Liquefaction-induced lateral spreading of soils caused by strong shaking requires careful evaluation to be properly accounted for in geotechnical, and structural design of strategic infrastructure located in highly active seismic coastal regions. Although a large number of empirical and semiempirical models are available, there is still a lot of inconsistency in their predictions. In recent years, using complex mathematical models to simulate the seismic response of potentially liquefiable soil deposits has become more common. However, the application of these models to evaluate lateral spreading is still too cumbersome in practice. This paper introduces a practice-oriented mathematical model for the estimation of lateral spreading. A one dimensional finite element time-domain formulation is used to represent the soil deposit for horizontal or sloping ground conditions. The soil behavior is controlled by a Mohr-Coulomb shear strength criterion, coupled with a pore pressure generation scheme based on the cyclic stress approach. Thus, the proposed model is able to simulate the loss of shear strength due to pore pressure generation during the earthquake. The elastic soil stiffness is modified according to the shear strain level. The model seems to be able to capture the predominant failure mechanism, and the ground movement variation with depth. Model predictions were compared with observed ground displacements for several case histories.