A critical state anisotropic model with state-dependent of sand
Li Xuefeng , Yuan Qi , Wang Xing
DOI:
Received February 11, 2015,Revised , Accepted , Available online July 22, 2015
Volume ,2015,Pages 70-78
- Abstract
Considering the impact of sand state on its critical state line, a constitutive model for anisotropic sand is established in the method of macro-micro incorporation. The novel anisotropy state variable is introduced into critical state equation of the model, the influences of anisotropic parameters, stress state and the relationship between stress and fabric direction on the equation is added and the state-dependent concepts of sand is extended. With the changes of stress state and the relationship between stress and fabric direction, the shape and the position of phase transformation-state, peak-state and critical-state of model is changed inartificially on the direction of hydrostatic pressure. The more degree of anisotropy, the further offset from the axes of hydrostatic pressure and the greater change in shape. The hardening law and dilatancy equation of model are the function of anisotropy state variable. The description of sand dilatancy and hardening law are refined and quantified with the change of microscopic quantification parameter. One set of model constants can describe the strength-deformation responses of sand under a large scale of confining pressures and densities.