论文部分内容阅读
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。
Through the uniaxial compression acoustic emission test of granite, the energy, frequency and frequency of acoustic emission signal in granite rupture process were extracted, and the three kinds of coupling relations in granite rupture process were analyzed: rupture scale and energy, energy and frequency, The relationship between energy and frequency. Using energy as a medium, the relationship between the rupture scale and the characteristics of acoustic emission signals (energy, amplitude and frequency) was discussed. The evolution of acoustic emission signals corresponding to different rupture scales during granite rupture was studied, and the acoustic emission Precursory laws. The results show that there are four kinds of acoustic emission signals in the process of granite rupture: low frequency high amplitude, low frequency low amplitude, low frequency intermediate frequency and high frequency low amplitude. Large-scale rupture acoustic emission in granite is characterized by low dominant frequency, high amplitude and high energy, corresponding to low frequency and high amplitude acoustic emission signals. Small scale rupture is characterized by low amplitude and low energy, low and medium high Acoustic emission coexist dominant frequency characteristics, corresponding to low-frequency low-amplitude, low frequency and high frequency low-amplitude three modes of acoustic emission signal. Medium and high frequency low amplitude and low frequency high amplitude three kinds of model AE signal suitable for prediction of the granite rupture the main source of signal characteristics of the precursors: medium and high frequency low amplitude signal gradually disappear, low frequency and high amplitude signal Appears, that appear in the high-frequency low-amplitude signal calm, low-frequency high-amplitude signal is not calm phenomenon. The precursory response coefficients of high-frequency low-amplitude and low-frequency high-amplitude signals are 0.2, and the precursors of low-amplitude IF signals are 0.14. Compared with the low-IF, high-frequency and low- Response time is early, precursor response ability is stronger.