特厚煤层综放大断面开切眼支护技术研究

Study on Open Hole Cutting Support Technology for Large Cross Section of Fully Mechanized Top-coal Caving in Extra Thick Coal Seam

以小庄煤矿40309切眼为工程背景,采用理论分析、理论计算和现场监测等方法对大断面切眼支护技术进行研究。研究结果表明:应力集中系数高、垂直应力大和裂隙发育是大断面切眼的失稳原因;建立了基于锚杆、锚索、金属网、槽钢及W型钢带协同支护系统;切眼顶底板移进量控制在98 mm,两帮移近量控制在50 mm。

Taking the 40309 hole cutting in Xiaozhuang Coal Mine as the engineering background,the large cross section hole cutting support technology is studied by means of theoretical analysis,theoretical calculation and on-site monitoring.The results show that high stress concentration factor,large vertical stress and crack development are the reasons for the instability of large cross section hole cutting,a cooperative support system based on bolt,anchor cable,metal mesh,channel steel and W-shaped steel belt is established,the movement of the low plate of the hole cutting roof is controlled at 98 mm and the approach of the two sides is controlled at 50 mm.