Stability analysis of residual pillar in the adjustment of mine pressure in the final mining stage of fully mechanized face

Mine pressure adjustment before fully mechanized mining face penetration ensures a smooth transfixion of the working face and safe equipment withdrawal. On the basis of an analysis of the applicable conditions of different strata pressure adjustment measures before penetration, the mechanical analysis model of the remaining coal pillar in final mining was established, and the functional relationship between the critical width of the coal pillar and the occurrence conditions of the surrounding rock, the physical and mechanical parameters, the engineering-related parameters, and the failure form of the main roof in final mining were obtained. The location of the main roof fracture, the depth of the working face, the nature of the strata, and the mining height are important in controlling the surrounding rock stability in the final mining stage. To ensure the coal pillar stability, the main factors mentioned above should be considered, especially when stopping mining is needed to adjust the mine pressure.