With the increasing depletion of shallow-earth mineral resources, deep mining will become the primary route of future mineral resources development. However, deep mining technology is a long way from being mature, and there are still a great number of issues that severely limit the growth of resources. In this paper, the acoustic emission (AE) tests of triaxially loaded and unloaded deep diorite are conducted. The results show that when confining pressure is at a low level, the failure mode of rock sample is mainly tension fracture; however as confining pressure increases, the failure mode gradually changes to shear failure. Under different stress paths, AE counting characteristics can be separated into four stages, including initial low-energy zone, pre-peak quiet zone, peak sudden burst zone and post-peak failure intensive zone (post-peak fast attenuation zone or post-peak high density zone). The damage variable is defined as the ratio of the AE count rate of a certain stage to the cumulative AE count rate of the failure process, and it accounts for the largest proportion at the stage of unloading confining pressure. In addition, when confining pressure increases, the damage variable changes from a flat growth to a rapid growth, with the abrupt transition occurring around the peak stress.

随着浅层矿产资源日益枯竭，深部开采将成为未来矿产资源开发的主要路线。但深部开采技术距离成熟还有很长的路要走，还存在大量问题严重限制资源增长。本文对深部闪长岩进行了三轴加载和卸载的声发射（AE）测试。研究结果表明，当围压较低时，岩样的破坏模式以张拉断裂为主；但随着围压的增加，破坏模式逐渐转变为剪切破坏。在不同的应力路径下，AE计数特征可分为四个阶段，包括初始低能区、峰前安静区、峰值突发区和峰后故障密集区（峰后快速衰减区或峰后高密度区）。损伤变量定义为某一阶段的声发射计数率与破坏过程累计声发射计数率的比值，在卸围压阶段所占比例最大。此外，当围压增加时，损伤变量从平坦增长变为快速增长，并在峰值应力附近发生突变。