Comprehensive Support Technology of Gob-side Entry Retaining in Soft Limestone Floor

For the problems that long hanging time and big hanging distance of gob-side entry retaining with hard roof and soft bottom easily cause the insufficient support strength of roadway ends and coal wall broken when the roof is weighted, the concept “to improve the support strength, to strongly achieve roof cutting along gob” is proposed; three kinds of roof support schemes are designed, such as single hydraulic prop roof cutting and anchor net roof protecting, concrete roof cutting and anchor net roof protecting, dense single hydraulic prop roof cutting and anchor net roof protecting; taking the gob-side entry retaining of the limestone roof and mudstone floor in Binhu Coal Mine as an example, through numerical simulation and in-situ monitoring, it is shown that bolt-mesh + single hydraulic pillar roof cutting and anchor net roof protecting is the optimal support scheme, which can effectively control the roof sinking and realize the roof cutting.