Research on mechanism of surrounding rock instability and coupled support in deep high-stress roadway

Deep mine roadway engineering faces increasingly complex geological environments, with issues like “three highs and one disturbance” requiring urgent solutions. The stress field distribution in roadway surrounding rock has become more intricate. Addressing the characteristic of severe deformation in high-stress roadway surrounding rock, this study focuses on the bottom yard of the new auxiliary shaft at Qianyingzi Coal Mine. It comprehensively employs field measurements, laboratory experiments, and industrial-scale testing. This study analyzes the instability mechanisms of high-stress deep-level roadway surrounding rocks, proposes a coupled deep-shallow support technique to optimize grouting parameters for determining optimal support parameters. Field industrial-scale testing is subsequently conducted. Results indicate: the roadway surrounding rock exhibits low mechanical properties and contains clay minerals like kaolinite, which swell upon water exposure; the surrounding rock features well-developed fractures with extensive failure zones. The proposed “anchor-mesh-cable-grouting + coupled shallow-deep hole grouting” combines support technique yields optimal grouting parameters. Field industrial trials confirmed this support technique effectively controls deformation and failure in deep high-stress roadways, providing both theoretical support and practical case studies for similar roadway support applications.