石英二长闪长玢岩单轴岩爆试验声发射前兆特征研究

Analysis on Acoustic Emission Precursor Characteristics in Uniaxial Rock Burst Test of Quartz Diorite Porphyrite

采用MTS 815电液伺服测试系统与PCI-Ⅱ型声发射监测系统,对石英二长闪长玢岩样进行单轴加载岩爆模拟试验。根据试验过程中声发射信号的活跃程度,将声发射振铃计数划分为4个时期,分别为初始密集期、平静期、峰前密集期和岩爆期,并结合非均匀性指标Cv值的峰值及增长趋势,研究试件在岩爆模拟试验过程中的声发射信号前兆特征。结果显示,在平静期内声发射振铃计数表现为低值稀疏,峰前密集期表现为密集增长,及其非均匀性指标Cv值的"突增"现象,可作为该类岩石岩爆发生的声发射前兆特征信号。

Using MTS 815 electro-hydraulic servo test system and PCI-II type acoustic emission monitoring system,uniaxial loading rock burst simulation tests were carried out on quartz diorite porphyrite samples.According to the active degree of acoustic emission signal during the test,the acoustic emission ringing count was divided into four periods,namely,initial dense period,quiet period,pre-peak dense period and rock burst period.And combined with the peak value and the increasing trend of the inhomogeneity index Cv,the precursor characteristics of acoustic emission signal in rock burst simulation test were studied.The results showed that in the quiet period,the number of acoustic emission ringing count showed a low value of sparse,while in the density period before peak it showed a dence growth,and a sudden increase of the inhomogeneity index Cv value.It could be used as the acoustic emission precursor characteristic signal in rock burst of this kind of rocks.