Nonlocal modification of the Gurson - Model

The mesh dependence of some problems in damage mechanics is assumed to be mainly due to errors introduced by the homogenization process. To correct these errors, a nonlocal formulation is proposed. As in the nonlocal theory of elasticity, the formulation of the internal work has been extended by a nonlocal term. From a global statement of equilibrium for a structure composed of representative volume elements (RVE's), equations are obtained which have to be satisfied for every single RVE. In order to deal with a two-dimensional problem, only the case of long cylindrical voids in a ductile matrix material under generalized plane strain conditions has been considered. The resulting nonlocal modification of the yield condition will be discussed