SYMMETRY-BREAKING FRACTURE IN RANDOM FIBER NETWORKS

Effective-medium approximation and computer simulations were employed to study the fracture of a two-dimensional fibre network of random topology at densities well above the percolation threshold. As strain is increased adiabatically, the fracture process changes from a two-dimensional <<percolationlike>> process to a one-dimensional uncorrelated process. The stress-strain curve has a discontinuous size-dependent drop at the transition and a non-universal tail at high strain.