A Finite Elastoplastic Constitutive Formulation With New Co-rotational Stress-Rate and Strain-Hardening Rule

Abstract

A constitutive model for finite elastoplastic deformations is presented. This model incorporates two novel features: first, a strain-hardening law that is applicable to complex loading paths and histories; and second, an objective stress-rate measure that is based on the spin of an orthogonal triad of material unit vectors which instantaneously coincides with the principal directions of the stress tensor. Problems of shear superposed on triaxial tension, cyclic shear deformation, and biaxial nonproportional loading are studied. It is shown that realistic predictions for the aforementioned problems are obtained by using the proposed constitutive model.