Layout of stopping line position and surrounding rock control technology for fully mechanized coal mining face with complex stress field

Taking the 93^upper24 working face of Nantun Coal Mine, Yankuang Energy as the engineering background, this study comprehensively employs theoretical analysis and FLAC^3D numerical simulation, combined with field mine pressure monitoring and verification, to investigate the reasonable position of the stopping line and the surrounding rock control technology for the exploratory roadway. When both sides of the working face are mined out, the distance between the final mining area and the north-side goaf should be greater than 98.6 m to ensure coal pillar stability. The coal pillar width for the exploratory roadway should be greater than 5 m; the distance from the stopping line to the exploratory roadway is about 5 m on the track roadway side and about 9.8 m on the conveyor roadway side, which is finally optimized to 9 m on the conveyor roadway side and 5 m on the track roadway side. When the working face advances 5 m past the stopping line, the peak stress in front of the coal wall reaches 40–45 MPa, which can easily cause anchor cable failure in the exploratory roadway. Field monitoring shows that when the distance from the exploratory roadway is less than 5 m on the track roadway side or less than 9 m on the conveyor roadway side, roadway deformation increases significantly. Therefore, setting the stopping line of the 93^upper24 working face at about 9 m on the conveyor roadway side and about 5 m on the track roadway side is reasonable. The associated surrounding rock reinforcement and support technology for the exploratory roadway can effectively control roadway deformation, balance the requirements of coal pillar stability and roadway deformation control, and provide a technical reference for similar working faces under complex stress fields.