Studies on parameters in constitutive relation for elastic/plastic analysis of soil mass

Based on the definition of continuous media of thermodynamics,the complementary correlation between free energy and dissipation energy triggered by external forces was identified first under iso-thermal deformation condition.And,the state variables including effective stress,elastic strain,plastic strain,and plastic strain increment were incorporated into both dissipated and free energy potential functions.Then,the equivalent application of the function of state on describing energy locus transfer inside the system was developed to create a more reasonable layout of yield condition,flow rule and hardening law of critical state constitutive model.This paper concentrated on selecting the parameters for the elastic/plastic constitutive model of soils and how to interpret the actual physical phenomena.And,the goal was to improve the ability of this model in describing constitutive behavior of soils through incorporating new parameters into the extended critical state constitutive model.Moreover,through this introduction of critical parameters,the present model was more realistic to describe anisotropic constitutive behavior of different types of soils.The numerical model,based on the effort of model verification,could precisely provide numerical simulation data which provided better consistent simulation with field monitoring data than Mohr-Coulomb model and modified Cam-clay model.