It is pretty challenging and difficult to quantitatively evaluate the intensity of dynamic disasters in deep mining engineering. Based on the uniaxial loading-unloading experiments for five types of rocks, this paper investigated the energy evolution characteristics, and identified the damage and crack propagation thresholds. Also, the fragment size distributions of the rocks after failure were analyzed. The energy release rate (G_e) and energy dissipation rate (G_d) were then proposed to describe the change of energies per unit volume and per unit strain. Results demonstrated that the more brittle rocks had the shorter stage of unstable crack growth and the lower induced damage at crack damage thresholds. The evolution characteristics of the strain energy rates can be easily identified by the crack propagation thresholds. The failure intensity index (FI_d), which equals to the values of G_e/G_d at the failure point, was further put forth. It can account for the brittleness of the rocks, the intensity of rock failure as well as the degree of rock fragmentation. It was revealed that a higher FI_d corresponded to a lower fractal dimension and stronger dynamic failure.

在深度采矿工程中，定量评估动态灾害的强度是非常困难且困难的。基于五种类型岩石的单轴加载-卸载实验，研究了能量演化特征，确定了损伤和裂纹扩展阈值。此外，分析了破裂后岩石的碎片尺寸分布。能量释放率（G _e）和能量耗散率（G _d然后提出来描述每单位体积和每单位应变的能量变化。结果表明，脆性更大的岩石具有更短的不稳定裂纹扩展阶段，并且在裂纹损伤阈值处的诱导损伤较低。裂纹扩展阈值可以很容易地识别出应变能速率的演化特征。进一步提出了失效强度指数（FI _d），该指数等于失效点的G _e / G _d值。它可以解释岩石的脆性，岩石破坏的强度以及岩石破碎的程度。据透露，更高的FI _d 对应较低的分形维数和较强的动态破坏。