A STRESS-UPDATE ALGORITHM FOR VISCOPLASTIC SOLIDS AT LARGE STRAINS

Existing constitutive structures for the modeling of rate-dependent el astoviscoplastic material response - for example of the PERZYNA-type [ 1], the DUVAUT-LIONS-type [2] or general overstress-types [3] - imply different structures of stress-update algorithms. We refer to [4] for a comparative discussion of these models. Within this paper we concent rate our attention to a recently developed constitutive model for larg e-strain viscoplasticity of the overstress-type MIEHE & KECK [4]. As a n important feature, the proposed algorithm preserves the decoupling o f the constitutive model into equlibrium stress and overstress respons e.