Application of Two Different Constitutive Models for Numerical Simulation of Liquefaction

Liquefaction phenomenon in saturated loose sandy layers occurs as an undrained response of soil when it is subjected to static or dynamic loads. A fully coupled dynamic numerical program is developed to predict the liquefaction potential of saturated sandy layers. Coupled dynamic field equations of extended Biot’s theory with u-p formulation are used to determine pore fluid and soil skeleton responses. Generalized Newmark method is employed for integration in time. The soil behavior is characterized with densification model as well as a critical state two-surface plasticity model for sands. A class B analysis of experiment No.1 of the VELACS project is performed to simulate the dynamic response of level sand sites. In this analysis a horizontal liquefiable layer was excited horizontally. Computed results are compared to those recorded in centrifuge tests. The obtained numerical results demonstrate the capability of the model to simulate the liquefaction phenomenon within the critical state soil mechanics framework.