Constitutive Model for Long-Term Behavior of Saturated Frozen Soil

Abstract

In this paper a two stress-state variables model with solid phase stress and cryogenic suction is introduced for simulating the long-term behavior of frozen soils. The solid phase stress is introduced as the combined stress of soil grains and ice. The model is able to represent the behavior of frozen soils in different temperatures and ice contents with a single set of parameters. It is also able to simulate the transition between frozen and unfrozen states. The so-called over-stress method is applied for simulating the elastic-viscoplastic deformation of the material due to variation of solid phase stress, while an elastic-plastic formulation is applied for the suction induced deformation. In unfrozen state, the model becomes a conventional elastic-viscoplastic critical state model. The model is implemented in PLAXIS and results are compared with the available test data and reasonable agreement is achieved.