Construction Technology of Water-retaining Wall after Water and Sand Bursting in the Aquifer of Coal Mine Roof

Taking the water and sand burst disaster of No.2 coal return air roadway in Maiduoshan Coal Mine of Yuanyanghu Mining Area in Ningdong as an example, using the simplified calculation method of equilibrium theory and taking the size of roadway and the nature of surrounding rock as the constrains, the physical and mathematical models for calculating the compressive and shear strength of the water-retaining wall were established. The safe head height of the wall and the surrounding rock was calculated quantitatively, and the concrete block water-retaining wall in flat type was constructed. It is calculated that when the depth of the surrounding rock groove is 0.5 m, the thickness of the blocks on both sides is 0.5 m, and the concrete pouring thickness is 1.0 m, the strength requirements can be met. The construction technology of this type of water-retaining wall is put forward to provide a protective barrier for the recovery of production, and realize the safety management of the water and sand burst disaster of the No.2 coal roadway in Maiduoshan Coal Mine.