Attractive and repulsive cracks in a heterogeneous material

TL;DR

This study experimentally investigates crack interactions in a heterogeneous brittle material under uniaxial stress, revealing two distinct crack path types influenced by collective statistical processes.

Contribution

It identifies and characterizes two different crack interaction behaviors in heterogeneous materials, highlighting the role of collective statistical mechanisms in crack path selection.

Findings

Two types of crack paths observed: repulsive-then-attractive and purely attractive.

Crack path type selection is a statistical collective process.

Only one crack path type occurs in each sample.

Abstract

We study experimentally the paths of an assembly of cracks growing in interaction in a heterogeneous two-dimensional elastic brittle material submitted to uniaxial stress. For a given initial crack assembly geometry, we observe two types of crack path. The first one corresponds to a repulsion followed by an attraction on one end of the crack and a tip to tip attraction on the other end. The second one corresponds to a pure attraction. Only one of the crack path type is observed in a given sample. Thus, selection between the two types appears as a statistical collective process.