Lai Xingping, Jia Chong, Cui Feng, Chen Jianqiang, Zhou Yupu, Feng Ganggui, Gao Yuanjiang
College of Energy Engineering, School of Energy Resources, Xi'an University of Science and Technology, Xi'an, 710054, China.
State Key Laboratory of Coal Green and Safety Development in West China, Xi'an, 710054, China.
Sci Rep. 2022 Jun 27;12(1):10832. doi: 10.1038/s41598-022-14538-7.
In the process of deep mining of coal resources, coal seams with better geological conditions are gradually mined preferentially, and the safe and efficient mining of working face in complex and heterogeneous spaces of residual coal seams is an urgent problem to be solved.. Based on the Kuangou Coal Mine as the background, using microseismic monitoring instruments and pressure sensor monitoring systems, the rock pressure appearance and microseismic energy characteristics accompanying the evolution of the overburden strata structure in the mining of solid coal and the lower working face of the gob are analyzed. Research on the precursory characteristics and early warning of micro-earthquakes. The research results show that: (1) The period of the W1123 working face mining under solid coal is relatively frequent, and the energy of microseismic events is higher than that under the mined-out area. However, the overlying rock structure under the gob is loose, broken and easy to move, showing obvious "high frequency-low energy" characteristics. (2) Extremely low values of the number and energy of microseismic events occurrs in the first 3 to 5 days of the rockburst event in the working face, and the locations of the rockburst disaster in the mine were generally distributed at the edge of the low-density area of the microseismic event. The accuracy of rockburst prediction is effectively improved through multi-parameter comprehensive early warning. (3) Roof deep hole blasting and roof cutting pressure relief weaken the roof energy accumulation and the concentrated release of rock formation energy, reduce the roof activity intensity in the microseismic event gathering area, and reduce the occurrence of large-energy events, which will easily induce large shock hazards. The energy event weakens into a slow release of multiple small energy events. This research provides a reference for the safe and efficient mining of working faces in complex space environment.
在煤炭资源深度开采过程中，地质条件较好的煤层逐渐被优先开采，残煤在复杂非均质空间工作面的安全高效开采成为亟待解决的问题。以沟煤矿为背景，利用微震监测仪器和压力传感器监测系统，分析了实体煤开采及采空区下部工作面开采过程中覆岩结构演化伴随的矿山压力显现及微震能量特征，开展微地震前兆特征及预警研究。研究结果表明：（1）实体煤下W1123工作面开采期间微震活动相对频繁，微震事件能量高于采空区下方，但采空区上方覆岩结构松散、破碎、易移动，呈现明显的“高频低能”特征。（2）工作面冲击地压事件发生前3～5天微震事件数量及能量出现极低值，矿井冲击地压灾害位置一般分布在微震事件低密度区边缘，通过多参数综合预警有效提高了冲击地压预测的准确性。（3）顶板深孔爆破和顶板切顶卸压削弱了顶板能量积聚及岩层能量集中释放，降低了微震事件聚集区顶板活动强度，减少了大能量事件发生，将易诱发大冲击危害的能量事件弱化成为多个小能量事件的缓慢释放。该研究为复杂空间环境下工作面的安全高效开采提供了参考。
