应力波作用下岩石声发射实验研究

摘要

Experiments were made on a SHPB system and the AE law of a rock under action of stress wave was obtained.The experimental results showed that the AE signals are few before the peak of the energy occurs; and the AE energy presents two different features: (1) the energy decays rapidly after the peak of the energy occurs, however, the energy rises at the end of the loading and the "inflection point"appears; (2) the energy decays slowly after the peak energy occurs and the "inflection point"does not appear.The study results indicated that the AE energy features closely relate to the rock fragmentation levels; the AE under action of stress wave not only reflects the information of cracks, but also that of stress wave signals.%在霍普金森(SHPB)冲击系统上进行了应力波作用下岩石声发射实验,获得了该加载条件下岩石破裂的声发射规律.实验结果表明,应力波下,声发射峰值能量之前所出现的声发射信号相当匮乏;而且其能量规律呈现出两种明显不同的特征:I型,声发射峰值能量之后,能量迅速衰减,到了加载的末期,能量出现了一定的回升,产生了"拐点";Ⅱ型,声发射峰值能量之后,能量衰减相对Ⅰ型较慢,且不出现"拐点".研究结果表明,声发射的能量特征与岩石破碎的程度密切相关;冲击载荷作用下岩石的声发射不仅仅是裂纹信息的反映,其中也包含了对应力波信号的反映.