China Coal Energy Group Co., Ltd.
China Coal Shaanxi Yulin Energy and Chemical Co., Ltd.
Coal Mining & Designing Department, Tiandi Science & Technology Co., Ltd.
CCTEG Coal Mining Research Institute

具有厚硬顶板的矿井在采掘期间将面临矿震、矿压显现强烈的风险，易导致矿井发生动力灾害事故。为对此类风险隐患进行预控和防范，需要对矿井的厚硬顶板进行预控处理。采用现场调研、工程类比、理论分析、实验室试验和数值模拟的方法，对矿井岩层赋存特征、潜在矿震风险、厚硬顶板可压裂性和地面压裂预控矿震风险机理进行研究。理论分析得到具有厚硬顶板的矿井不仅存在单一工作面低位、高位厚硬顶板初次破断诱发矿震风险，也存在随矿井开采空间增大加剧高位厚硬顶板诱发矿震的风险性；蒙陕地区类似条件工程案例类比表明，具有厚硬顶板赋存条件、开采条件的矿井，自第2个工作面开采始具有发生较高的矿震风险的可能；通过厚硬顶板可压裂性试验研究得到岩石脆性系数为59%～143%，平均脆性矿物含量约68%，综合表明所研究矿井的厚硬顶板可压裂特性较好；模拟对比分析得到在厚硬顶板预裂后，工作面超前支承压力集中程度和超前影响距离均明显降低。基于厚硬顶板的研究结果，提出了矿井地面压裂区域卸压矿震风险预控技术，即通过地面实施“L”型钻孔至厚硬顶板进行压裂，以降低厚硬顶板完整性和致密性。工程应用表明，在实施地面压裂区段中，井下压裂区域微震事件的最高频次降低了52.2%，微震事件的最大能量释放降低了56%，由此说明厚硬顶板的地面压裂预控技术成功降低了矿震风险，保障了工作面的安全顺利回采。

Mines with thick and hard roof face high risks of mine seismic activities and mine pressure during mining, which easily leads to dynamic disasters in mines. To pre-control and prevent such risks, it is necessary to pre-control the thick and hard roof of the mine. By field investigation, engineering analogy, theoretical analysis, laboratory test and numerical simulation, the occurrence characteristics of mine strata, potential mine seismic risk, fracturing of thick and hard roof and the mechanism of ground fracturing pre-control mine seismic risk are studied. The theoretical analysis shows that the mine with thick and hard roof not only has the mine seismic risk induced by the first breakage of the low and high thick and hard roof of a single panel, but also has the risk of aggravating the mine seismic event induced by the high thick and hard roof with the increase of the mining void of the mine. The analogy of engineering cases with similar conditions in Inner Mongolia and Shaanxi shows that mines with thick and hard roof occurrence conditions and mining conditions have the possibility of high mine seismic risk since the second panel is mined. Through the fracturing test of thick and hard roof, the rock brittleness coefficient is 59%~143%, and the average brittle mineral content is about 68%. The comprehensive results show that the fracturing characteristics of the thick and hard roof of the mine are better. The simulation comparison analysis shows that after the pre-splitting of the thick and hard roof, the concentration degree of the front abutment pressure and the front influence distance of the working face are obviously reduced. Based on various research results of thick and hard roof, the mine seismic risk pre-control technology using local ground fracturing pressure relief method is put forward, that is, fracturing is carried out by ‘L’ type drilling on the ground to thick and hard roof to reduce the integrity and compactness of thick and hard roof. The engineering application shows that in the fractured section, the highest frequency of microseismic events in the underground section is reduced by 52.2%, and the maximum energy release of microseismic events in the section is reduced by 56%. This shows that the ground fracturing pre-control technology of thick and hard roof successfully reduces the mine seismic risk and ensures the safe and smooth extraction of panels.

国家重点研发计划资助项目（2022YFC3004604）；中煤集团重大科技专项资助项目（20211BY001）

王书文，智宝岩，杜涛涛，等. 厚硬顶板潜在矿震风险地面压裂预控技术[J]. 煤炭科学技术，2023，51（11）：1−11.

WANG Shuwen，ZHI Baoyan，DU Taotao，et al. Ground fracturing pre-control technology for potential mine seismic risk of thick and hard roof[J]. Coal Science and Technology，2023，51（11）：1−11.