花岗岩灾变声发射信号多参量耦合分析及主破裂前兆特征试验研究

 通过开展花岗岩单轴压缩声发射试验，提取花岗岩破裂过程声发射信号的能量、主频和主频幅值，分析花岗岩破裂过程中3种耦合关系：破裂尺度和能量、能量和主频幅值、能量和主频的关系。以能量为媒介，探讨破裂尺度和声发射信号特征(能量、幅值和主频)之间的对应关系，研究花岗岩破裂过程中不同破裂尺度对应声发射信号的演化规律，探索岩石破裂的声发射前兆规律。研究结果表明：花岗岩破裂过程中存在4种模式声发射信号：低频高幅值、低频低幅值、中频低幅值和高频低幅值。花岗岩破裂过程中大尺度破裂声发射表现为低主频、高幅值和高能量的特征，对应低频高幅值声发射信号；小尺度破裂表现为低幅值和低能量，低、中和高主频共存的声发射特征，对应低频低幅值、中频低幅值和高频低幅值3种模式声发射信号。中、高频低幅值和低频高幅值3种模式声发射信号，适合作为花岗岩破裂预测的主要信号源，前兆特征表现为：中、高频低幅值信号逐渐消失，低频高幅值信号出现，即出现中、高频低幅值信号平静，而低频高幅值信号不平静的现象。高频低幅值和低频高幅值信号的前兆响应系数为0.2，中频低幅值信号前兆响应系数为0.14，相比中频低幅值信号，高频低幅值和低频高幅值信号的前兆响应时间早，前兆响应能力较强。

Multi parameter coupling analysis of acoustic emission signals of granite disaster and the precursor characteristics of the main rupture

Uniaxial compression AE test of granite was carried out. The energy，dominant frequency and amplitude of dominant frequency of AE signal in the process of granite burst were extracted to study the three kinds of coupling relationships between the rupture length and energy，between the energy and amplitude of dominant frequency and between the energy and dominant frequency. The correspondence between the rupture scale and AE signal characteristics(energy，amplitude and dominant frequency) was discussed in terms of energy. The variation of AE signal corresponding to the different rupture scales in the course of rock fracture was the focus of the study. The AE precursor of rock burst was investigated. Four modes of AE signals in the process of granite rupture were found，including the low frequency and high amplitude，the low frequency and low amplitude，the intermediate frequency and low amplitude，and the high frequency and low amplitude. In the process of granite rupture，the characteristics of large scale fracture AE was characterized by the low frequency，high amplitude and high energy，which corresponded to the AE signals of low frequency and high amplitude. The AE characteristics of small scale rupture showed the low amplitude and low energy，coexistence of the low，medium and high dominate frequency，corresponding to the three modes of AE signals：the low frequency and low amplitude，the intermediate frequency and low amplitude，and the high frequency and low amplitude. There are three modes of AE signals：the intermediate frequency and low amplitude，the high frequency and low amplitude and the low frequency and high amplitude，which are suitable as the main signal source for the prediction of the rupture of granite. The characteristics of the precursor are as follows：the intermediate and high frequency low amplitude signals disappear gradually，and the low frequency high amplitude signals appear，which is the phenomenon of the medium and high frequency low amplitude signal being quiet and the low frequency high amplitude signal being not quiet. The precursor response coefficient of the high frequency low amplitude and low frequency high amplitude signal is 0.2，and the one of the intermediate frequency low amplitude signal is 0.14. The precursor of response time of high frequency low amplitude and low frequency high amplitude is earlier.