Improved Predictions of Liquefaction-Induced Lateral Spreading with SANISAND-MSf: Incorporating Effects of Static Shear Stress

This study presents an improved numerical model for simulating cyclic liquefaction-induced lateral spreading. The enhancement is achieved by incorporating the effects of static shear stresses on the undrained cyclic shearing of sands in the SANISAND-MSf constitutive framework. This improvement allows the model to capture the undrained response of sands for different densities and stress states. The model is implemented in the finite element-based platform OpenSees for application to dynamic problems. The performance of the model is assessed by simulating cyclic direct simple shear tests and centrifuge experiments of mildly inclined liquefiable sand deposits, specifically designed to study lateral spreading. The results of the simulations demonstrate the effectiveness of the SANISAND-MSf model in replicating the liquefaction response observed in the centrifuge experiments, including the triggering of cyclic liquefaction and the subsequent development of large shear strains, which are key drivers of lateral spreading. The improved predictive capabilities of this constitutive model, particularly through the incorporation of the effect of static shear stresses, can help to better assess and mitigate the risks associated with liquefaction-induced lateral spreading during earthquakes.