Study on key parameters of roof cutting and retaining roadway in medium-hard roof of the inclined working face in Changcheng No.6 Mine

In order to control the destabilization of surrounding rock along the roadway of 1301S working face of Changcheng No.6 Mine, firstly, the numerical simulation method of UDEC is adopted to reveal the movement law of lateral overburden breakage of 1301S working face, and finds that the locations of lateral overburden breakage are located in the upper part of the roadway, and the length of cantilever structure of immediate roof is about 1.8 m; secondly, through the construction of the lateral overburden structural mechanics model, the analytical expressions of supporting stresses in the solid coal and gangue support before and after roof cutting have been obtained, and according to the expression of the case analysis, the solid coal supporting stress before and after the roof cutting is kept unchanged, both of which are 1.27 MPa, and the supporting stress in the gangue support body near the left side of the roadway is reduced by 56.89%; thirdly, the parameters of the roadway side roof cutting are determined by theoretical calculations, the height of the roof cutting is 11 m, the angle of the roof cutting is 20°, and the spacing of the cut-off holes is 500 mm; finally, roof cutting and retaining roadway technical program of 1301S working face transporting roadway is planned and carried out in industrial test. The research results show that after roof cutting, the displacement of roof and floor two sides of the roadway is 1 240 mm and 265 mm, respectively, compared with the non-roof cutting are reduced by 12.68% and 70.22%, and the overall stability of the surrounding rock is good. This study can provide reference for the application of the technology and design of key parameters of roof cutting and retaining roadway under the same or similar conditions.