THE INFLUENCE OF INTERNAL-STRESSES ON THE FRACTURE OF HETEROGENEOUS MEDIA

We study numerically the influence of random internal stresses on the fracture properties of brittle solids. We consider an electrical analo g network model where internal stresses are the only source of disorde r. We study the scaling of the fracture properties with the system siz e and with the degree of damage. We argue that some properties of this model can be compared with previously studied models where disorder w as introduced through different properties of the constituents. In add ition, internal stresses in a purely brittle system lead to new effect s as a coarse-grained level such as an apparent plasticity, absent at the local level.