复合顶板大采高采场覆岩破断角实测及其演化规律研究

基于申南凹煤矿的实际工程背景,对复合顶板大采高条件下覆岩破断角的发育情况展开深入研究.通过对高位钻孔抽采数据的长期观测,对采场侧的覆岩破断角进行了计算;利用双塞压水实验研究了采空区回风巷侧覆岩破断角;最后利用UDEC模拟分析了采空区覆岩破断角的演化过程.研究结果表明:工作面推进速度3.6m/d时,采场侧的覆岩破断角为5...

Study on Measurement and Evolution Law of Mining Fracture Angle of Large Mining Height Overburden in Composite Roof

The determination of the fracture angle is critical to the design of gas extraction boreholes in goaf. However, The existing re-searches mostly stay on the basis of numerical simulation and similar material simulation, and lack effective verification of field measured data. Based on the actual situation of Shen Nanwa Coal Mine, this paper conducts an in-depth study on the development of the fracture angle under the condition of large mining height of composite roof. Through the long-term ob-servation of the high-level drilling extraction data, the fracture angle along the working face side is calculated; The lateral fracture angle of the goaf was studied by double plug water test; Finally, UDEC numerical simulation is used to analyze the evolution process of overburden mining fissures and fracture angles. Research indicates: when the surface advancing speed is 3.6m/d, the fracture angle of the working surface side is 59°, and the lateral fracture angle of the goaf is 58° at 100~110m behind the working surface; The fracture angle is in a dynamic process that will gradually change over time, up to 109°. The obtained research results can provide theoretical basis for the study of drilling arrangement and gas migration and enrichment in goaf.