一种立方体监测网络的声发射源和微震源解析定位方法

摘要

通过选取合理的坐标原点及传感器位置简化声发射源定位方程,得到声发射源或微震源三维定位方法的解析解.算例研究表明,对于传感器阵列内、外的声发射源事件,解析方法定位结果完全与实际坐标一致;对于传感器阵列内的声发射源事件,传统方法略有误差,一般为0.01-0.03 m,而对于传感器阵列外的微震源,传统时差定位方法的定位误差很大,最大的达到1080986m;采用横截面为100mm×98mm、长度为350mm的花岗岩试样,进行5次断铅定位实验,分别用传统方法和解析方法进行定位,结果发现在监测网络外的4个声发射事件,解析定位的误差亦小于传统方法的定位误差.可见解析定位精度较传统方法有明显提高,最高可提高17.61 mm;利用解析解定位,无需确定拟合初值和拟合迭代算法,仅通过简单的四则运算即可定位,用常规的计算器或Microsoft Excel即可求解.%To find the analytical solution of the acoustic emission/microseismic(AE/MS)source location coordinates,the sensor location coordinates were optimized and simplified.A cube monitoring network of sensor location was selected,and the AE/MS source localization equations were established.A location method with P-wave velocity by analytical solutions(P-VAS)was obtained with these equations.The virtual location tests show that the relocation results of analytical method are fully consistent with the actual coordinates for events both inside and outside the monitoring network;whereas the location error of traditional time difference method is between 0.01 and 0.03 m for events inside the sensor array,and the location errors are larger,which is up to 1080986 m for events outside the sensor array.The broken pencil location tests were carried out in the cross section of 100 mm×98 mm,350 mm-length granite rock specimen using five AE sensors.Five AE sources were relocated with the conventional method and the P-VAS method.For the four events outside monitoring network,the positioning accuracy by P-VAS method is higher than that by the traditional method,and the location accuracy of the larger one can be increased by 17.61 mm.The results of both virtual and broken pencil location tests show that the proposed analytical solution is effective to improve the positioning accuracy.It can locate the coordinates of AE/MS source only using simple four arithmetic operations,without determining the fitting initial value and iterative calculation,which can be solved by a conventional calculator or Microsoft Excel.