关键词: 沿空留巷, 顶板结构, 切顶卸压, 巷旁支护

Abstract: Taking the gob-side entry retaining of 2401 transport roadway in Shunhe Coal Mine as the engineering background, the structural characteristics of surrounding rock of roadway are analyzed. Based on the stability of local spatial structure of roadway, the mechanical structure models of non-roof cutting and roof cutting of gob-side entry retaining are constructed respectively, and the physical similarity simulation test is carried out with different roof cutting heights of roadway. The results show that the gangue cut off in the goaf increases the support force to the key block, weakens the extrusion of the key block to the end of the direct roof hanging wall, and reduces the support resistance by 35.78 %. With the increase of roof cutting height, the cantilever on the goaf side end of roadway roof slowly transits from F type to large I type, and the large protection structure has the trend of upward translation. Compared with the uncut top 1 roadway, the superimposed stress peaks of 4cm roof cutting 2 roadway, 8cm roof cutting 3 roadway and 16cm roof cutting 4 roadway decrease by 9.38 %, 28.13 % and 25.00 % respectively. Combined with the roof lithology of the roadway, the roof cutting height is finally determined to be 8.2 m, and the retaining section adopts three columns of single hydraulic props as roadside support. The long and short anchor cables are reinforced in advance, and the surrounding rock of the roadway is stable, which can better meet the requirements of use.