Guili Peng, Xianguo Tuo, Huailiang Li, Yong Liu, Tong Shen, Jing Lu
Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, School of Information Engineering, Southwest University of Science and Technology, Mianyang 621010, China.
School of Geophysics, Chengdu University of Technology, Chengdu 610059, China.
Rev Sci Instrum. 2021 May 1;92(5):055102. doi: 10.1063/5.0048419.
Rock burst early warning technology is currently applied mainly in microseismic monitoring. Rock burst signals indicate the micro-fracture phenomena of a rock and can transmit earthquake waves through the rock before they are finally received by a detector. A characteristic decomposition of rock micro-fracture signals was conducted by the singular value Empirical Mode Decomposition (EMD) algorithm to effectively decompose the characteristic signals of a rock micro-fracture from mixed microseismic signals, with a low signal to noise ratio to ensure prediction precision. When comparing the proposed method with wavelet decomposition and EMD, it was found that the local characteristics of the signals were retained effectively. The proposed algorithm was verified by applying it in a laboratory simulation and to the decomposition of microseismic signals from a hydro-power station. It was concluded that the improved algorithm had a better decomposition precision than wavelet decomposition and EMD decomposition and could effectively separate the characteristic signals of micro-earthquakes. This could provide a significant basis for the identification of the abnormal microseismic signals of rock micro-fractures as well as a pre-warning of rock fractures. It is therefore of practical significance to study rock fracture early warning technology.
岩爆预警技术目前主要应用于微震监测。岩爆信号指示岩石的微破裂现象，并且在最终被探测器接收之前能够通过岩石传播地震波。利用奇异值经验模态分解（EMD）算法对岩石微破裂信号进行特征分解，以便从低信噪比的混合微震信号中有效分解出岩石微破裂的特征信号，从而确保预测精度。在将所提方法与小波分解和EMD进行比较时，发现能够有效保留信号的局部特征。通过在实验室模拟以及对某水电站微震信号的分解中应用所提算法进行了验证。得出的结论是，改进算法比小波分解和EMD分解具有更好的分解精度，并且能够有效分离微地震的特征信号。这可为识别岩石微破裂的异常微震信号以及岩石破裂的预警提供重要依据。因此，研究岩石破裂预警技术具有实际意义。
