Crack propagation in random materials: computational analysis

Abstract

Combining random features with continuum-damage mechanics and fracture mechanics, it is possible to study the effect of the brittle material’s strength randomness for a case of crack propagation. The mode-I fracture analysis based on discretisation of the cross-section of specimens containing a sharp notch into rectangular elements (cells) provides detailed information on the failure process. The effect of the initial damage (due to porosity) on the processes of damage accumulation and failure is analysed. A computational procedure for simulation of crack–damage interaction and crack propagation in porous alumina specimens at tension is suggested on the basis of a continuum-damage model, concept of local stress intensity factors and modification of a lattice scheme. The inhomogeneity of material properties is modelled in terms of initial damage distribution in the specimen’s cross-section.