Drift destressing in deep mines.

爆破是指在坚硬岩石中的深部矿井中，岩石从推进的巷道的工作面或井壁中不可预测且通常是猛烈地喷射出来。随着安大略省许多地雷埋深的增加，这些事件的发生率也在增加，这导致矿工受伤的风险增加。多年来，通常涉及爆破的减压技术已被开发出来，以缓解这一问题。减压爆破的目的是改变岩石的性质，从而降低开挖边界的高应力。对于这一过程的机制(气体压力和新裂缝的产生)，有不同的解释。这些机制尚未通过测量明确确定，也未确定将触发使用减压的条件。因此，目前的减压爆破设计完全是经验性的。

Strainbursting is the unpredictable and often violent ejection of rock from the face or sidewalls of advancing drifts in deep mines in hard rock. With the increasing depth of many mines in Ontario, the incidence of these events is increasing, which is leading to increasing risk of injury to mine personnel. Over the years, techniques known as destressing, which normally involve blasting, have been developed to alleviate this problem. The objective of destress blasting is to alter the properties of the rock mass in such a way that high stresses at the excavation boundaries are reduced. There are competing explanations for the mechanisms of how this works (gas pressure vs creation of new fractures). Those mechanisms have not been clearly identified through measurement, nor have the conditions been identified which would trigger the use of destressing. As a result, current design of destressing blasts is entirely empirical.