岩石破裂声发射过程的围压效应

CONFINING PRESSURE EFFECT ON ACOUSTIC EMISSIONS DURING ROCK FAILURE

针对由于地下开挖引起的岩石声发射率突增及最小主应力减小可能引起地震等地质现象，利用统计损伤理论对岩石破裂过程中声发射率的时间序列特征，特别是三维应力下岩石的快速加卸围压对声发射的影响进行了理论探讨。结果表明：三维应力下岩石快速卸围压，促使声发射率突增，而在一定范围内快速增加围压，声发射并不发生，只有增加一定轴压，才会有声发射的产生，这些结果在计算机上得到了很好的模拟。

Based on the phenomenon that acoustic emissions(AE) increase suddenly because of underground excavation, time sequence of AE rate during rock failure has been discussed by using statistical damage theory. Especially increasing or decreasing confining pressure results in variance of AE under three dimensional stresses. The results show that decreasing confining pressure sharply brings out increasing AE sharply. On the other hand, few AE emit when confining pressure increases sharply, and AE occur again only when axial pressure increases. These results have been well simulated with computer and agree well with experimental results.