Numerical study on time dependent and time independent fracturing processes for brittle rocks

Based on the physical observations of fracturing processes in brittle rocks, numerical modeling schemes are proposed considering material heterogeneity and initial microflaws at the element scale. Linear elastic fracture mechanical theory is adopted to define the mechanical conditions of a microcrack within each element, where failure criterion based on stress intensity factor is introduced. The kink model and wing crack propagation model are developed to describe the initiation and growth of microcracks. Numerical simulations are implemented under distinct loading types, where factors influencing model response are studied. Typical fracture patterns are observed under distinct external loads. The numerical models are able to reproduce the fracturing process of heterogeneous brittle rocks spatially and temporally. The simulation results have shown good agreement with laboratory observations. Conclusions were drawn and possible future work is discussed for the improvement of the current model.