Application of grouting for water blocking in roadway belt conveyor haulage system in Ningtiaota mine

Water inrush problem occurred during the excavation of roadway for No.3^-1 coal-seam belt conveyor haulage system in Ningtiaota mine,which made excavation process ceased.Based on the analysis of water-bursting characters and water-bearing characteristics,it's sure that water inrush was induced by the fracture in No.3^-1 coal-seam.The authors used full-face curtain permeation pre-grouting and reinforcing grouting in short holes on the mining faces to control water inrush problems.The results show that the combined method is effective and can ensure excavation process continue to 400 m long along No.3^-1 coal-seam and complete all roadway support work.