Mixed-mode crack growth simulation in rock-like materials with the smoothing gradient-enhanced damage model associated with a novel equivalent strain

Accurately modeling mixed-mode crack propagation in rock-like materials remains challenging due to the complexity of the deformation states and mechanism of fracture throughout the loading history. The objective of this paper is to analyze the damage process in rock-like materials using an enhanced smeared damage model. The mixed-mode failure in rocks is captured using our recently developed smoothing gradient damage model in conjunction with a novel equivalent strain formulation, which is developed by combining both the bi-energy norm equivalent strain and the four-parameter equivalent strain. To validate the accuracy of the developed method, several commonly reported rock fracture examples are considered in which complex crack paths and responses are reproduced and compared with the available experimental data.