Numerical study of the tangential inelastic effect of the Subloading Surface model on the nonproportional loading condition

摘要

Most of the conventional and unconventional plasticity models (Drucker, 1988) are not capable to catch a realistic material behavior when non-proportional loading conditions are applied. This limitation is due to the assumption of considering the plastic strain rate vector as independent from the stress rate, allowing the formation of the irreversible contributions only along the direction normal to the plastic potential. To overcome this drawback, the work presented in this paper will show how to take into account the effect of the tangential component of the stress rate inside a return mapping formulation for the Extended Subloading Surface model, allowing a fast and accurate numerical computation even for special loading conditions.