Abstract: In order to replenish the study of slate’s rockburst test, we carried out indoor rockburst test on slates from Jining by loading in three directions, gradual unloading from one surface, and then vertical gradual loading to simulate the rockburst of slate using deep rockburst simulation test system. Then we collected and screened the rockburst fragments, and calculated the fractal dimensions of fragments of particle size greater than 10mm according to different forms of rock. The results indicate that different forms of rock have influence on the fractal dimension which ranges from 1.62-2.73. The fractal dimensions of length, width, and thickness to quantity have the smallest discrete and can be taken as the preferred indicators. The degree of broken difficulty in thickness, length, width is enhanced gradually. In addition, the fractal dimensions of ratios of length to thickness, length to width and width to thickness could characterize strip, sheet, and block of fragments,respectively. The results of the test indicate that slate rockburst fragments are mainly strip, strip-block and block and the sheet feature of fragments is unobvious.

Key words: slate, indoor rockburst test, fragments, different forms of rock, fractal