Study On Gob-Side Entry Retaining Technology In Close 6# Coal Seam Of Xiangsheng Coal Mine

At present,with the continuous reduction of coal resources in mining areas,more and more scholars begin to pay attention to the mining of close seams.Now the coal industry is also demanding to take the road of green mining,which makes people more and more enthusiastic about the study of gob-side entry retaining technology in close-range thin coal seams.Based on the engineering background of Retaining Roadway along goaf in 6201 working face of Luyang Xiangsheng Coal Mine in Shouyang,Shanxi Province,this paper uses the methods of theoretical analysis,numerical simulation and engineering practice to analyze and study.The results are as follows:(1)Aiming at the characteristics of belt slot along 6201 working face in Xiangsheng Coal Mine,on the basis of comprehensive comparison and analysis of the advantages and disadvantages of three current gob-side entry retaining methods,it is concluded that Xiangsheng Coal Mine is more suitable to adopt the gob-side entry retaining method by filling with high-water roadway,and the filling technology along gob-side entry retaining with high-water is analyzed from two aspects of material performance and filling technology,which further demonstrates the 6201 working Rationality of Retaining Roadway along goaf with high water content.(2)Based on the stress analysis of the floor of the goaf after the mining of the upper coal seam,the stress calculation formula at any point of the floor under the goaf and the maximum yield failure depth of the floor rock are obtained.In view of the problem of stress concentration under coal pillars,the staggered arrangement can be used to avoid the stress concentration area when arranging grooves in the lower coal seam.(3)Based on the stress analysis of the roof of the retained roadway under the goaf,the mechanical model of the roof is established,and the mathematical formula for calculating the roof subsidence is obtained according to the principle of superposition method.The mechanical model of the deformation of the corpse coal side is established,and the mathematical formula for calculating the width of the plastic zone is given.(4)By using numerical simulation software,the advantages and disadvantages of retaining roadway under goaf are analyzed from the angle of vertical stress and plastic deformation,and the stress of backfilling body and solid coal side of retaining roadway are studied.Based on theoretical analysis,numerical simulation and engineering practice,the technology of gob-side entry retaining under the goaf of short-distance thin coal seam is studied.Some suggestions are put forward for other coal seams with the same occurrence conditions to retain roadways along goaf.