Stress strain relationship for anisotropically consolidated sand over a wide stress region

An anisotropic elasto-plastic constitutive model is presented in triaxial space in order to evaluate the stress-strain behaviour of anisotropically consolidated sands over a wide stress range for static loading conditions. The fundamental concept presented herein is based on the assumption that sand exhibits anisotropic hardening, dependent on both plastic volumetric and shear strains. The model presented consists of a yield function, plastic potential and hardening modulus, which are formulated based on a few basic assumptions and experimental evidence. The model contains eleven experimental parameters which are determined from a few conventional triaxial tests and also have a clear physical meaning. The predicted behaviour for drained and undrained triaxial tests is compared with available experimental data. It is shown that the modal accurately, represents the changes with increasing confining pressure in stress-strain behaviour for anisotropically consolidated sand.