The Strength Reduction Method in Clay Hypoplasticity

Abstract

An evaluation of the slope stability in FEM software is often performed as a complementary analysis to the plastic deformation analysis. The slope stability represented by the factor of safety is, in the most of FEM software, evaluated by the reduction of the strength parameters $c$ and $\varphi$ of the Mohr-Coulomb model. Consequently, the lack of the strength reduction method for the advanced constitutive models inevitably leads to its substitution by the Mohr-Coulomb model and necessity of a further recalibration of the constitutive model parameters. Therefore, new method of the strength reduction was developed for the Masin’s hypoplastic model for clays. A subsequent return of a deviatoric stress to the asymptotic state boundary surface is implemented in this method so that all the integration points within the FEM remain within asymptotic state boundary surface. Predictions of the newly developed method is thoroughly testes from the quantitative as well as qualitative point of view and eventually compared with the predictions of the Mohr-Coulomb model.