Damage accumulation in quasi-brittle fracture

TL;DR

This paper investigates how microcrack accumulation influences the strength and size effects in quasi-brittle materials using large-scale numerical simulations of the random fuse model.

Contribution

It provides new insights into the microcrack distribution evolution and its relation to damage accumulation and size effects in quasi-brittle fracture.

Findings

Broadening of microcrack distribution tail due to dominant microcracks

Crack coalescence increases with system size

Disorder level affects damage evolution

Abstract

The strength of quasi-brittle materials depends on the ensemble of defects inside the sample and on the way damage accumulates before failure. Using large scale numerical simulations of the random fuse model, we investigate the evolution of the microcrack distribution that is directly related to the strength distribution and its size effects. We show that the broadening of the distribution tail originates from the dominating microcracks in each sample and is related to a tendency of crack coalescence that increases with system size. We study how the observed behavior depends on the disorder present in the sample.