A three-dimensional multi-surface plasticity soil model for seismically-induced liquefaction and earthquake loading applications

This paper presents a three-dimensional (3D) multi-surface plasticity model to computationally simulate the behavior of coarse-grained granular soil during seismically-induced liquefaction. The model extends an existing multi-surface plasticity formulation and includes the Lade-Duncan failure criterion as the yield function to more closely capture salient characteristics of laboratory test data. Subsequently, flow rules are updated for modeling the essential shear response mechanisms associated with dilatancy, cyclic mobility, and post-liquefaction shear strain accumulation. The constitutive model is implemented into the OpenSees computational framework, and Finite Element (FE) calibrations are undertaken to match a set of laboratory test data, including drained monotonic/undrained stress-controlled cyclic triaxial tests, and a centrifuge test on a liquefiable sloping ground. It is demonstrated that the soil constitutive model and the employed computational framework can reasonably predict the seismic response of the liquefiable sloping ground under earthquake loading. On this basis, full 3D FE simulations of a typical bridge abutment seated on liquefiable sloping ground are conducted to further highlight underlying earthquake-induced liquefaction effects on the ground-structure system deformations. Overall, the developed constitutive model provides a useful tool for evaluating earthquake-induced soil liquefaction hazards and associated 3D ground seismic response scenarios.

Automated summary

This paper presents a three-dimensional multi-surface plasticity model to simulate the behavior of granular soil during seismically-induced liquefaction. The model extends an existing plasticity formulation and includes the Lade-Duncan failure criterion to capture laboratory test data. The model is implemented into the OpenSees framework and calibrated with laboratory tests to predict the seismic response of liquefiable ground.