煤矿井下微震震源高精度定位研究

煤矿井下微震震源准确定位,对于动力灾害监测预警具有重要意义.由于微震震源需要通过井下传感器接收信息反演确定,传感器的安装位置限制于煤矿井下巷道周围,传感器沿巷道近平面的不合理布置将大大降低震源定位精度.针对由传感器信息反演震源位置引起的病态问题,本文提出了基于微震监测测点优化布置的震源高精度定位算法.首先通过计算系数矩阵条件数,判定病态问题;然后利用中心化法和行平衡法联合进行病态矩阵预处理.对预处理后的矩阵A、b利用L曲线法计算正则参数,结合Tikhonov正则化算法计算得到震源坐标正则解.研究结果表明,中心化法有效降低了矩阵数量级,行平衡预处理降低了病态条件数,预处理后Tikhonov正则解的震源坐标误差最小可以达到3.09m,与预处理前的高斯消去解相比误差大大降低.通过上述优化处理,实现了井下受限空间微震监测震源高精度定位.

High precision location of micro-seismic sources in underground coal mine

Accurate location of micro-seismic sources in underground coal mine has great significance for monitoring and early warning of dynamic disaster. Micro-seismic source information is generally extracted through inversion of the data acquired by the underground sensors. The installation of the sensors is limited around underground roadway. The seismic location precision will be greatly decreased in the case of unreasonable arrangement of sensors along the roadway and approximately in a plane. As for the ill-posed problems caused by the inversion for source location with sensor-received information, high precision location algorithm of micro-seismic source based on monitoring points arrangement optimization is presented in this paper. Firstly, the ill-posed problems are judged by calculating the coefficient matrix condition numbers. The ill-posed matrix is then pretreated by centralization and row balance jointly. The regularization parameters of pretreated matrix A and b are calculated by the L-curve method. The seismic source coordinates regularization solution is obtained using Tikhonov regularization algorithm. The results show that the matrix magnitude is decreased effectively with centralization method, ill-posed condition numbers are reduced with row balance pretreatment. The minimum seismic source coordinate error of Tikhonov regularization solution after pretreatment is 3.09 m, and is greatly decreased compared to the error by Gaussian elimination solution before pretreatment. High precision seismic source location is realized in limited space of underground roadway by means of the above optimization processing.