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Abstract In view of the technical problem that the roadway of coal pillar recovery working face is easy to induce the instability of roof structure when it passes through the empty roadway, the 3-edge 18 coal pillar recovery working face of Jingfang Mine crossing the track, transportation, auxiliary return air roadway and multiple contact roadways of the fifth mining area was taken as the research object, the stress evolution law and deformation response characteristics of surrounding rock in the process of coal pillar recovery working face crossing the empty roadway were revealed by the combination of theoretical analysis and engineering monitoring. It was found that the extension distance of the advance stress disturbance zone of the working face was 9 m, and the convergence of the surrounding rock on the goaf side of the abandoned roadway was significantly higher than that on the solid coal side, showing a typical asymmetric deformation mode. In the 18 m operation section before the roadway penetration, the ' four-column single-beam ' enhanced support system was adopted and the propulsion trajectory optimization control strategy was implemented to ensure the integrity of the support structure by adjusting the mining horizon parameters. The ' anchorage system + hydraulic support unit + auxiliary pillar ' collaborative bearing system was constructed. The engineering verification results showed that the composite support scheme effectively suppressed the risk of roof collapse.
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