Constitutive model for sand considering the variation of its physical state

Based on the theory of critical state and current used model the state parameters are introduced into the stress-dilatancy equation and the plastic hardening modulus expression to develop a new constitutive model for sand. By using this model the effect of relative density and the changing of physical state due to the variation of relative density and effective confining pressure on strength and deformation characteristics in the process of loading can be described.The model is convenient to be used, only 8 model parameters are involved. It is shown to be suitable for both drained and undrained cases. The numerical simulation is in good agreement with the data of triaxial compression tests.