The phase-field simulations of blasting failure in granites

In this study, an explicit phase-field model with new mixed-mode fracture driving forces is developed to simulate the blasting fracture phenomena in granites. The new fracture driving forces make our new phase-field model able to capture pure tensile crack, pure shear cracks and other mixed-mode tensile/compressive-shear cracks in rock/rock-like materials. To validate the correctness and accuracy of our new dynamic phase-field framework, two benchmarked examples, i.e., a Kalthoff-Winkler test and a laboratory borehole blasting experiment, are performed by the qualitative and quantitative comparisons. Furthermore, a series of borehole blasting tests of granites are simulated by our new numerical model. The effects of blast loading parameters (i.e., peak pressure, loading rate and blasting attenuation) and mineral components on the dynamic failure characteristics of granites, including ultimate failure patterns, breakage ratio, energy evolution, peak particle velocity, are systematically investigated. Overall, this study not only offers a useful computational tool to the researchers in rock mechanics, but also provides deep insights on the dynamic rock fracture to the engineers in rock engineering.

Automated summary

In this study, a new explicit phase-field model with mixed-mode fracture driving forces is developed to simulate blasting fracture in granites. The model is able to accurately capture various fracture modes in rock materials. The correctness and accuracy of the model are validated through qualitative and quantitative comparisons with benchmarked examples and laboratory experiments. The model is then used to simulate a series of borehole blasting tests, allowing for investigations on the effects of blast loading parameters and mineral components on the dynamic failure characteristics of granites. This study provides a useful computational tool for researchers in rock mechanics and offers insights on dynamic rock fracture to engineers in rock engineering.