Causes, characterization, damage models, and constitutive modes for rock damage analysis: a review

The analysis of damage process and the characterization of damaged rock masses through numerical models are the most difficult and challenging tasks in geotechnical engineering. This review paper describes and collects information regarding the causes of damage in the rocks and damage models (constitutive and hybrid damage models) for rock damage analysis. The main objective of this review is to discuss the causes of damage process, characterization, constitutive modes, and impact of natural changes on the selection of damage model. The review suggests that releasable strain energy, crack propagation and coalescence, joints, natural changes, and engineering disturbance are the main causes of rock fracture and damage. Most studies showed that a wider range of rock mass characterization will be required to create an ideal numerical model due to the rock reality, inelasticity, fractures, anisotropy, and inhomogeneity. Hybrid models are more efficient computationally as compared with the constitutive models. The review concludes that numerical models are also applicable tools to understand damage scale, damage degree and type, damage location, and damage occurrence time in the rocks.