Study On Selection Of Roadway Protection Mode And Surrounding Rock Controlling Under Fracture Line Of Thick Hard Roof

This article focuses on under the condition of hard roof covering, and firstly considers whether we can use our own shearing resistance of backfill along goaf side of marginal micro leakage at the distance of7m, so as to achieve the full effect of the pressure-relief. In order to prevent9203leaving roadway along goaf roadway beside the wall in hard roof being crushed when facing the roof pressure, especially with high early strength, the test adopts the ash filling materials of increased speed and high water to build a roadside filling body. If not,9203working face belongs to high gas and inflammable coal face, so unloading blast technology cannot being employed, so it will remain in gob with narrow coal pillar technology. Although this absence technique of gob coal recovery rate is high, but there is a relatively low cost, and can prevent air leakage in goaf coal spontaneous.The consideration of the break line location must be taken when9203caving to avoid tunnels beneath the old top break location heading and additional narrow coal pillar. The break position is3-5m, and coal column width of protecting lane is4.6-6.3m in minimum. When fracture line is in the top left pillar above the coal pillar, under pressure at this time. The test takes the seam spontaneous combustion coal seam into account, and comes to the conclusion that additional pillar bearing area is necessary. Finally, reasonable coal pillar of roadway width in the9203mining face is decided as7m, and the bolt-mesh-anchor supporting scheme is put forward.