Microstructural Damage-Induced Localized Fracturing of Brittle Rocks

In this paper, localized damage and failure process of brittle rock in compression is investigated using rock failure process analysis (RFPA) model. The model accounts for material heterogeneity to capture the cooperative interaction between microcracks in the transition from distributed to localized damage and the temporal and spatial evolution of acoustic emission during the progressive damage process. Correspondingly, a series of numerical compressive tests on rock specimens are performed to investigate the damage evolution and localized fracturing of brittle rock. The study shows that heterogeneity and scale of specimen have significant effect on damage localization and failure mode of rock specimens. In addition, post-peak response of stress-strain curve is due to the deformation of the structural elements, and localization means that the descending branch of the stress-strain curve of specimen is size dependent and the stress-strain curve can therefore not be regarded as a pure material property.