密集孔切顶卸压技术在无煤柱开采中应用研究

Research on Application of Dense Hole Cutting Roof Pressure Relief Technology in Pillarless Mining

为减少煤炭资源浪费,解决姜家湾矿资源枯竭,缓解采掘接替紧张压力,根据矿井开采煤层的实际情况,在7号层305盘区南翼工作面采用密集孔切顶卸技术沿空留巷,实现无煤柱开采。本文以7号层8514工作面为实例,结合该工作面的地质情况,介绍了密集孔切顶卸压沿空留巷原理,通过模拟计算和工程实践确定了密集孔施工参数(孔深6 m,孔径50 mm,倾角75°,间距350 mm)。同时,在原有巷道支护的基础上,距两巷帮0.7 m增加2列21.8 mm×8 mm锚索进行补强支护,在距采空侧0.2 m,支设2排单体柱,柱距0.5 m,排距0.6 m,铺设2.2 m×1.1 m金属网挡矸。通过矿压监测和现场实测,留设巷道能够满足相邻面使用。

In order to reduce the waste of coal resources,solve the depletion of Jiangjiawan mine resources,and ease the tension of mining replacement,according to the actual situation of coal mining in the mine,the dense hole cutting and top-unloading technology is adopted in the south wing working face of the 305 panel on the No.7 layer.Keep lanes to realize coal-pillar-free mining.In this paper,taking the No.7layer 8514 working face as an example,combined with the geological conditions of the working face,the principle of cutting the top of the dense hole and leaving the roadway along the goaf is introduced.Through simulation calculation and engineering practice,the dense hole construction parameters(hole depth 6m,The aperture is 50mm,the inclination angle is 75°,and the spacing is 350mm).At the same time,on the basis of the original roadway support,two rows of 21.8mm ×8mm anchor cables are added 0.7m away from the two roadways for reinforcement and support.At 0.2m away from the goaf,two rows of single columns are supported.0.5m,row spacing 0.6m,Lay 2.2 m×1.1m metal mesh to block the gangue.Through mine pressure monitoring and on-site measurement,the reserved roadway can meet the use of adjacent surfaces and can achieve better economic benefits.