大断面复合顶板回采巷道锚网支护技术

Support Technology of Anchor Net in Mining Roadway with Large Section and Composite Roof

针对某煤矿大断面复合顶板回采巷道具体地质条件,采用理论分析和现场实践相结合的方法,对大断面复合顶板巷道支护方式进行了研究分析。理论分析得出,增大支护阻力Pb,可以控制巷道围岩塑性区的发展,而肩部和底角是巷道受力大、最容易破坏的位置。计算得出,巷道围岩最大破坏范围最大为1.39 m,结合现场实际确定顶板锚杆采用Ф20 mm的螺纹钢锚杆,长度为2.5 m,间排距为1 000 mm×900 mm。现场实测得出,工作面巷道顶底板移近量累积最大为108 mm,两帮移近量累积最大为98 mm,巷道顶板最大离层量为55 mm,支护效果良好,研究成果可为其他矿区大断面复合顶板煤层开采提供依据。

According to the certain geological features of the mining roadway with a large cross section and composite roof in a coal mine, combined theoretical analysis and practice, the paper provided the combined support plan with anchor net support. Theory analysis concluded that increased support resistance Pb can control the development of the surrounding rock plastic, that bottom corner and the shoulder of the roadway are most likely to undermine the position of the roadway. After the calculation, the maximum damage extent of the surrounding rock is 1.39 m, combined with the actual site, the roof bolt are determined to use the screw steel bolt Ф20 mm, length 2.5 m,inter-array spacing 1 000 mm× 900 mm. The field measurement shows that the maximum distance of working face roadway roof and floor are accumulated to 108 mm, the maximum distance of two sides are accumulated to 98 mm, the maximum distance of roadway roof abscission layer are 55 ram, and the roof supporting achieved good results, the research achievements can provide basis for other mines which have large section of comnosite roof seams.