Influence of different soil constitutive models on ssi effect on a liquefiable site

Abstract

With the rapid development of computer science and computational techniques, numerical simulations are regarded as powerful tools to solve complex geotechnical problems such as soil-structure interaction effects on liquefiable sites. For the simulation of soil liquefaction, soil constitutive models play important role in the correctly reproducing and interpreting the behavior liquefied soil and so as to the consequent soil structure interaction (SSI) problem. In this study, a comparative work was carried out to investigate the influence of different soil constitutive models on SSI effect on a liquefiable site. Two well know soil constitutive models are exploited: SANISAND model (Dafalias et al. 2004) and Hypoplastic model (von Wolffersdorff 1996). These two numerical models were first numerically implemented by semi-explicit 3rd order Runge-Kutta integration scheme with adapting sub-steps. The numerical implementation is done by UMAT subroutines in Abaqus. The model parameters of these two constitutive models were calibrated using triaxial test data of Fontainebleau sand (NE34). The performance of these two constitutive models is investigated numerically by comparing the seismic responses of a shallow foundation on the same liquefiable site. Results show that although these two constitutive models can be calibrated successfully against oridinary triaxial test data, their performance in terms of a real case SSI are different. The possible reasons are also disccussed in this study.