Mining Branch,China Coal Research Institute Department of Mining and Design, Tiandi Science and Technology Company Limited

为提高矿井微震信号b值计算效率和准确性,以孟村矿井掘进期间实际发生微震事件为样本,围绕b值计算过程中所涉的样本及参数选取等问题开展研究。不同发震区域微震演化机制及规律不同,b值计算样本的选取应以发震区域为基本单位,发震区域的范围由内部所有发震单元的关联微震事件分布确定。低震级事件缺失导致b值计算结果大幅偏小,可通过分析相关系数变化趋势确定最佳起始震级。在设置最高档次震级时,应考虑样本高震级端的频次分布情况,使得最高档次对应的微震频次与其理论值相当,并保证推移时间窗过程中,非空档次总数不变。时间窗过短时,b值计算结果易受随机异常因素影响。而时间窗过长时,b值因早期历史数据影响过大而波动偏小,在时间序列上的可区分性差。相对于能量、频次曲线,b值变化曲线更加平稳,表现出阶段性的高(低)值区间,对高能事件的提示效果优于能量、频次曲线。

in order to improve the calculation eficiency and accuracy of the mine microseism signal bvalue,based on the actual microseism event occurred during the mine heading period of Mengcun Mine as the sample, a study was conducted on the sample,parameter selection and other problems related to the b value calculation process. In the different seismic occurred area,the microseism e different,the selection of the b value calculation sample should be the seismic occurred area as the base unit and the seismic occurred scope should be determined with the related microseism event distribution of the inner all seismic unit. Due to lackof the low seismic event,thus the b value calculation results would be highly reduced.The best initial seismic grade could be determined with the analysis on the related coefficient varation tendency. When the high level seismic grade was set up.the frequency rate disribution condition of the high seismic grade of the sample should be considered and the microseism frequency and the theoretical value related to the highest grade were quite same. In order to ensure the pushing process of the time windows,the total umber of the neutral gear would not be changed. When the time window too short,the b value calculation results would be easily infuenced by the random abnormal factor. But when the time window was too long,due to early historical data infuence too high,the b value would be too low and the reparability on the time series would be poor.Related to he variation curve of the b value would be more stable and would have the sectional high(1ow) value zone. The prompt effect of the energy eventwould be better than the energy and frequency curves.

国家重点研发计划资助项目(2016YFC0801401)；天地科技开采设计事业部青年创新基金资助项目(KJ-2015-TDKC-05)；