坚硬顶板综放面覆岩垮落及导水裂隙研究

Study on Overburden Caving and Fissure Conductive Water of Hard Roof in Fully Mechanized Caving Face

以北辛窑煤矿2#煤首采面开采为背景,采用物理相似模拟的方法,运用全站仪与钻孔电视研究了坚硬顶板综放面覆岩垮落特征及导水裂隙带发育高度。结果表明:8103首采面来压步距大,煤层回采后覆岩表面导水裂隙带高度为115~135 m;关键层发生破断时覆岩表面位移变化明显,煤层回采后距开切眼240 m处地表沉降达到5 m以上;通过对煤层回采后1#钻孔内部裂隙分析,认为中下部和下部垮落覆岩是储水和导水的主要空间,对1#和2#钻孔不同回采距离下内部裂隙发育高度分析可得,导水裂隙带高度最终稳定在125.2~128.2 m,这对工作面两带高度确定和防治水措施的制定,具有重要的指导意义。

Based on the mining of No.2 coal seam in Beixinyao coal mine,the caving characteristics of overburden and the development height of water conducting fracture zone in the hard roof fully mechanized caving face are studied by using the method of physical similar simulation with total station and borehole televiewer.The results show that the pressure step distance of 8103 first mining face is large,and the height of water conducting fracture zone on the surface of overburden after coal mining is about 115 to 135 m;when the key layer breaks,the displacement of overburden surface changes obviously,and the surface subsidence of the coal seam is more than 5 m at 240 m away from the openoff cut after mining;through the analysis of the internal fracture of No.1 borehole after coal mining,it is considered that the middle and lower overburden is the main reservoir and water conducting rock It can be concluded from the analysis of the development height of internal fractures under different mining distances of No.1 and No.2 boreholes that the height of the water conducting fracture zone is finally stable at 125.2 to 128.2 m.This is of great significance to the determination of the height of the two zones in the working face and the formulation of water control measures.