Fractal characteristics of rock fragmentation process induced by indenters

The rock fragmentation process induced by indenters is numerically simulated by using the finite element method based on the Mohr-Coulomb criterion. The fractal dimension is calculated by using the box-counting method based on the fractal theory. The investigation shows that the rock fragmentation process induced by indenters has fractal characteristics. The rock fragmentation process can be classified into three significant stages. In these three stages fractal dimension has different variation trends. The fractal dimension can be used to characterize the rock fragmentation process induced by indenters effectively. When the displacement at the top reaches a critical value, the fragmentation crater appears. At the same time, the fractal dimension reaches a critical value which remains unchanged. The critical value can be used to characterize the fragmentation degree of rock quantitatively.