A first-order perturbation analysis of 3D crack propagation in heterogeneous materials under pure mode I loading

To unravel how the microstructure affects the fracture properties of heterogeneous brittle materials like rocks and ceramics we conducted a first-order perturbation analysis of 3D crack propagation under pure mode I loading in materials with randomly distributed tough inclusions. The influence of the microstructural features on the macroscopic fracture behavior is investigated. In particular, we will discuss how the inclusion density and toughness controls the effective toughness of the sample as well as the fracture surface roughness and the intermittent crack dynamics. Our numerical findings will be compared with experimental results based on 3D-printed heterogeneous samples.