A COMPUTATIONAL FRAMEWORK FOR A CLASS OF FULLY COUPLED MODELS FOR ELASTOPLASTIC DAMAGE AT FINITE STRAINS WITH REFERENCE TO THE LINEARIZATION ASPECTS

A fully coupled model for finite strain elastoplastic damage, based on the multiplicative decomposition of the deformation gradient, which i ncorporates non-linear isotropic and kinematic hardening is described. The numerical integration of its constitutive equations is performed by an algorithm which generalizes the standard return mapping procedur es of the infinitesimal theory. The exact, consistent linearization of the model described is carried out in detail. It provides the basis o f the full Newton-Raphson procedure for iterative solution of the asso ciated equilibrium problem. By means of finite element simulations, th e performance of the exact tangent modulus derived is compared with an approximate version and some practical implications are discussed.