大柳塔煤矿沿空留巷柔模砼墙合理宽度研究及应用OA北大核心CSTPCD

Aiming at the problem of the width of the flexible concrete wall of the gob-side entry retaining in shallow coal seam,the 52605 working face of Daliuta coal mine is taken as the engineering background.Using the methods of similar simulation test,numerical simulation and theoretical analysis,the reasonable width of flexible formwork concrete wall in gob-side entry retaining with large mining height is systematically studied.The mechanical model of gob-side entry retaining with flexible formwork concrete wall is constructed.The research results show that with the increase of the size of the concrete wall,the asymmetric deformation of the flexographic concrete wall becomes more obvious in the process of the stope roof rotation and subsidence.There is no obvious correlation between the stress concentration on the side of the solid coal wall and the size of the flexible formwork concrete wall in the mining stage of the working face.When the width of the concrete wall is 1.2 m,it can meet the support strength of the roadway,the deformation of the surrounding rock is small,and the stress concentration will not occur at the shoulder of the roadway.In the field measurement,1.2 m wide concrete wall is adopted,the maximum deformation of the roof and floor is not more than 287 mm,and the maximum deformation of the concrete wall is not more than 120 mm.The displacement of surrounding rock in mining roadway shows a trend of increasing first and then stabilizing.The research conclusion provides a theoretical reference for the determination of the width of the supporting body beside the gob-side entry retaining in the working face with large mining height.