Two-scale damage modeling of brittle composites

This paper is aimed at developing a non-local theory for obtaining a numeri cal approximation to a boundary-value problem describing damage phenomena i n a ceramic composite material. The mathematical homogenization method base d on double-scale asymptotic expansion is generalized to account for damage effects in heterogeneous media. A closed-form expression relating local fi elds to the overall strain and damage is derived. Non-local damage theory i s developed by introducing the concept of non-local phase fields (stress, s train, free energy density, damage release rate, etc.). Numerical results o f our model were found to be in good agreement with experimental data from 4-point bend tests conducted on composite beams made of Blackglas (TM) /Nex tel 5-harness satin weave. (C) 2001 Published by Elsevier Science Ltd. All rights reserved.