大采高工作面合理煤柱尺寸优化设计

Optimum Design of Reasonable Coal Pillar Size for Large Mining Height Working Face

针对枣泉煤矿大采高工作面巷道围岩控制难题,对不同区段煤柱宽度下的巷道顶板离层、巷道表面位移量、顶锚杆与帮锚杆受力情况、煤柱裂隙发育情况进行现场监测。监测结果表明,10 m煤柱巷道与20 m煤柱巷道最大离层量相差不大,巷道围岩变形量均较大,2种参数煤柱反映出两帮锚杆强度不足,大部分超过杆体屈服载荷,应提高两帮锚杆的杆体强度与直径;20 m煤柱巷道的两帮移近量、顶底板移近量比10 m煤柱巷道大,10 m煤柱巷道的巷道稳定比20 m煤柱巷道滞后70 m左右。采用理论计算方法确定煤柱合理宽度为15.2 m,结合现场监测结果,最终确定枣泉煤矿大采高工作面合理煤柱宽度为14~18 m。

Aiming at the problem of surrounding rock control of roadway in large mining height working face of Zaoquan Coal Mine,the roof separation of roadway,the displacement of roadway surface,the stress of roof bolt and side bolt,and the development of coal pillar fracture under different section coal pillar width were monitored.The monitoring results show that there is little difference between the 10 m coal pillar roadway and the 20 m coal pillar roadway in the maximum delamination amount,and the surrounding rock deformation of the roadway is larger.The two parameter coal pillars reflect the insufficient strength of the bolts of the two sides of the roadway,and most of them exceed the yield load of the rod body,so the strength and diameter of the bolts of the two groups of bolts should be improved.The approaching amount of the two sides,roof and floor of the 20 m coal pillar roadway is larger than that of the 10 m coal pillar roadway,and the roadway stability of the 10 m coal pillar roadway is about 70 m behind that of the 20 m coal pillar roadway.The theoretical calculation method is used to determine the reasonable coal pillar width of 15.2 m.Combined with the on-site monitoring results,the reasonable coal pillar width of the large mining height working face in Zaoquan Coal Mine is finally determined to be 14~18 m.