Fracture in concrete: X-ray tomography with in-situ testing, digital volume correlation and phase-field modeling

TL;DR

This study combines X-ray tomography, digital volume correlation, and phase-field modeling to analyze and simulate mesoscopic cracking in concrete, providing detailed insights into fracture behavior at the mesoscopic scale.

Contribution

It introduces an integrated experimental and computational approach that explicitly models mesostructural features of concrete during fracture analysis.

Findings

Good agreement between experimental and numerical results.

Effective modeling of mesostructural heterogeneity.

Enhanced understanding of crack propagation in concrete.

Abstract

We test and simulate the mesoscopic cracking behavior of specimens made of a standard concrete mixture. To this end, we combine stable wedge-splitting fracture experiments performed during X-ray tomography, their analysis with digital volume correlation providing the full three-dimensional displacement field, and phase-field cohesive fracture modeling. In our computations, we apply the measured boundary conditions and model the actual heterogeneous material structure at the mesoscopic scale. Within the phase-field model, we explicitly distinguish among (thus individually represent) the mesostructural features of distinct material phases with size above a threshold of 1 mm, while we homogenize pores and finer aggregates below this threshold within the cementitious mortar matrix, with material parameters characterized accordingly. We compare experimental and numerical results in terms of both local and global quantities.