Hu Liangping, Zhang Yongjiang, Huang Zhenfei, Li Quangui, Wang Hu, Hu Zhifang
State Key Laboratory of Coal Mine Disaster Dynamics and Control, School of Resources and safety Engineering, Chongqing University, No.174 Shazhengjie, Shapingba, Chongqing 400044, China.
China Coal Technology and Engineering Group Chongqing Research Institute, No. 6 Kecheng Road, Jiulongpo, Chongqing 400037, China.
ACS Omega. 2023 Feb 17;8(8):7639-7647. doi: 10.1021/acsomega.2c07240. eCollection 2023 Feb 28.
According to the characteristics of coal-rock dynamic disasters and hydraulic slotting, the mechanism of dynamic load barrier and static load pressure relief in hydraulic slotting is proposed. The stress distribution in a coal mining face and the slotted area of a section coal pillar is analyzed by numerical simulation. The results show that the slot formed by hydraulic slotting can effectively alleviate the stress concentration and transfer the high-stress area to a deeper coal seam. When slotting and blocking the dynamic load propagation path in a coal seam, the wave intensity of the stress wave transmitted into the slot is greatly reduced, so the risk of a coal-rock dynamic disaster is reduced. A field application of hydraulic slotting prevention technology was carried out in the Hujiahe coal mine. An investigation of microseismic events and an evaluation of the rock noise system show that the average event energy within 100 m mining mileage decreased by 18%, the microseismic energy per unit footage decreased by 37%, the times of strong mine pressure behavior evaluated in the working face decreased by 17%, and the number of risks decreased by 89%. In conclusion, hydraulic slotting technology can effectively reduce the risk of coal-rock dynamic disasters in mining faces and provides a more effective technical means for coal-rock dynamic disaster prevention.
根据煤岩动力灾害和水力割缝的特点，提出了水力割缝的动载屏障和静压卸压机理。通过数值模拟分析了采煤工作面和区段煤柱割缝区域的应力分布。结果表明，水力割缝形成的割槽能有效缓解应力集中，将高应力区转移到更深的煤层。当在煤层中割缝并阻断动载传播路径时，传入割槽的应力波的波强会大幅降低，从而降低煤岩动力灾害的风险。在胡家河煤矿开展了水力割缝防冲技术现场应用。微震事件调查和矿震系统评估表明，开采里程100 m范围内平均事件能量降低了18%，单位进尺微震能量降低了37%，工作面评估的强矿压显现次数降低了17%，风险次数降低了89%。综上所述，水力割缝技术能有效降低采煤工作面煤岩动力灾害风险，为煤岩动力灾害防治提供了更有效的技术手段。
