When the shaft passes through water-bearing strata or fractured zones, and the estimated water inflow exceeds 65438+ 100 m3/h, the ground or working face pre-grouting method should be adopted for water plugging or reinforcement.

In the well section located in quicksand layer, the depth of grouting hole must be less than 200mm. When double-wall support is used in the shaft, the grouting hole should pass through the inner wall and enter the outer wall100 mm. When the shaft wall is broken and needs to be grouted, special measures must be made.