Anchored Bolt Supporting Technology for Coal Roadway in Soft and Extremely-thick Coal-seam and Its Practice in Luning Mining Area

In order to solve difficult problem of anchored bolt supporting soft and extremely-thick coal-seam in Lu’ning Mining Area,geo-mechanical parameters were tested and the influence of key parameters of anchored bolt supporting including anchored length,prestress and its diffusion on supporting effect was simulated.Anchored property of coal and rock body was tested on the site.Based on this,anchored bolt and cable supporting system with high pre-stress was put forward to control surrounding rock deformation and supporting system structure was optimized.Actual application showed that this system could effectively control deformation and provide key reference for this style roadway in Lu’ ning Mining Area.