A computational model for interfacial damage through microstructural cohesive zone relaxation

A model introducing cohesive zones around material interfaces to simulate i nterfacial damage in microheterogeneous materials is developed. The materia l behavior within the cohesive zones is unknown a-priori, and is weakened, or "relaxed", on the continuum level from an initially undamaged state, by a reduction of the spatially variable elasticity tenser's eigenvalues. This reduction is initiated if constraints placed an the microstress fields, fo r example critical levels of pressure or deviatoric stresses, are violated. Outside of the cohesive zones the material is unaltered. Numerical computa tions are performed, employing the finite element method, to illustrate the approach in three dimensional applications.