Study on deformation and failure law of surrounding rock of fully mechanized mining face passing through empty roadway group

The disordered mining of coal seam in complex geological conditions leads to a large number of empty roadway groups left over, and the problems of complex rock pressure development and difficult surrounding rock control are faced in the process of fully mechanized mining face passing through nearby empty roadway groups. In order to study the deformation and failure law of surrounding rock of fully mechanized mining face passing through empty roadway group, the numerical simulation method is used to study the displacement, stress and plastic zone changes of surrounding rock before and after the mining of the same layer empty roadway, through layer empty roadway and underlying empty roadway in Nantun Coal Mine. The results show that the main factors affecting the failure of empty roadway are the relationship between empty roadway and coal seam, the distance between empty roadway and coal seam, and the change of empty roadway angle. When the distance between the empty roadway and the coal seam is less than 5 m, the damage of the empty roadway is serious. When the distance between the empty roadway and the coal seam is greater than 5 m, the deformation of the empty roadway gradually decreases; when the distance between the empty roadway and the coal seam is greater than 10 m, the empty roadway is less affected by mining. The phenomenon of stress concentration is easy to occur at the corner of empty roadway. In view of different types of empty roadway, the measures of slope adjustment, local filling and strengthening support of empty roadway are put forward. The measured results indicate that the working resistance of the hydraulic support and the stress of the coal and rock mass are relatively stable, and the control effect on the surrounding rock in the empty roadway is satisfactory. The research results can provide reference for similar fully mechanized mining face to safely pass through empty roadway group.