Numerical simulation and experimental investigation on rock fragmentation under combined dynamic and static loading

The numerical simulation method is applied to analysis the granite fragmentation process under static loading, impact loading and combined static and dynamic loading by ANSYS . The results show that the range of rock propagating cracks under static loading is wider and the angle of fragmentation bigger than that under impact loading; the crack growth rate in the rock under impact loading is faster than under static loading, which forms the smaller angle of fragmentation; the depth and area of rock fragmentation under combined loads are larger than static or dynamic loading and the crushing effect is better than the single loading model. By the multifunctional testing device for rock fragmentation, the breaking tests of granite under static loading, impact loading and combined static and dynamic loading are carried out. The test results further suggested that the breaking effects of rock are greatly improved under combined static and dynamic loading in the breaking depth, broken-volume and specific energy consumption compared with static loading and impact loading. The specific energy consumption of rock fragmentation is different for the different combined loading, reasonable ratio of dynamic loading to static loading can make the specific energy consumption least and breaking effect optimal.