Implicit numerical integration of an advanced subloading surface clay and sand model

Resumo

This paper focuses on the algorithmic and computational aspects of implementing the clay and sand model (CASM) using a fully implicit numerical scheme. CASM is a unified critical state model that relies on the state parameter concept and incorporates a non associated flow rule. Within this framework, the subloading enhancement is introduced, which enables a smooth elastic-plastic transition through an isotropic modification. The addition of just one extra parameter significantly enhances the calibration process. Subsequently, the modified version of CASM is implemented into a finite element procedure. The demonstrate the efficiency and good performance of the proposed algorithm, including the subloading modification, simulations of triaxial compression tests

under undrained conditions are conducted.