Damage-cluster distributions and size effect on strength in compressive failure

TL;DR

This paper models compressive failure in heterogeneous brittle materials, revealing that damage-cluster distributions and size effects support a critical fracture interpretation, with failure strength following a normal distribution and minimal size dependence.

Contribution

It introduces a damage model capturing local damage and analyzes damage-cluster distributions, providing insights into the critical nature of fracture and size effects in compressive failure.

Findings

Damage-cluster size distribution supports critical fracture behavior

Failure strength follows a normal distribution with small size effect

Model reproduces key features of brittle material failure

Abstract

We investigate compressive failure of heterogeneous materials on the basis of a continuous progressive damage model. The model explicitely accounts for tensile and shear local damage and reproduces the main features of compressive failure of brittle materials like rocks or ice. We show that the size distribution of damage-clusters, as well as the evolution of an order parameter, the size of the largest damage-cluster, argue for a critical interpretation of fracture. The compressive failure strength follows a normal distribution with a very small size effect on the mean strength, in good agreement with experiments.