Simulation of anisotropic deviatoric response of Hostun sand in true triaxial tests.

A critical state model is described within the framework of infinite surface bounding surface/kinematic hardening plasticity. The model can account for both initial anisotropy developing during sample preparation and subsequent evolution of anisotropy in samples along anisotropic loading paths. This model is then used to simulate the anisotropic behaviour of Hostun sand observed in series of stress probing tests conducted in a true triaxial apparatus within a single deviatoric stress plane in stress space. The selection of constitutive parameters for the model is discussed and the model evaluated. Deviatoric stress response envelopes are used to show the deviatoric strains generated in complex tests and as a vehicle for comparison of experiment and simulation. Three plausible deviatoric flow rules are compared and found to have modest differences in their ability to match the experimental response.