Experimental study on rockburst fragment characteristic of granite under different loading rates in true triaxial condition

In order to study the effect of loading rate on rockburst, an indoor test single-face fast unloading-three directions and five-face stress-vertical continuous is conducted under different rates using a new true-triaxial rockburst system. The entire process inoculation-occurrence-development completely accurately reproduced. fragmentation degree, fractal dimension, Weibull distribution characteristics fragments are compared analyzed. results indicate that ejection failure can be summarized as four stages: grain ejection, rock spalling into plates, shearing fragments, fragment ejection. Rockburst mostly coarse-grained, medium-grained, fine-grained. macroscopic block reflect degree rock, increases with rate. dimension shows same trend rates, is, grows increases. As increases, crack expansion accelerates, which aggravates damage specimen by decreasing its compressive strength causing greater when failed. has significant energy consumption fragments.