WATER CUT-OFF WORK FOR INNER SURFACE OF HOLE EXCAVATED UNDER GROUND

PURPOSE:To easily obtain a dangerless treating or depository place by connecting an inorganic water-proof layer coated on the surface of cement mortar layer on the hole side and a water-tight synthetic resin sheet provided on said inorganic water-proof layer by using a synthetic resin laminate. CONSTITUTION:A cement mortar layer 3 is formed on the side 2 of a hole 1 excavated under the ground, and an inorganic water-proof layer 7 is provided on the surface of the cement mortar layer 3. A synthetic resin laminate 6 both sides of which are laminated with nonwoven cloths is bonded to a proper place in the water-proof layer 7, and the bottom of the hole 1 and the water-proof layer 7 close to the bottom and the laminate 6 are covered with a water-tight synthetic resin sheet 5' in such a way as to connect the sheet 5' and the water-proof layer 7 with the laminate 6. In this case, before the water-proof layer 7 coated and bonded is hardened, the laminate layer 6 is pressed, the nonwoven cloth on one side of the laminate 6 is integrated with the water- proof layer 7, and then the water-proof layer is hardened. Afterwards, the nonwoven cloth on the other side and the sheet 5' are fixed with hot melt bonding, etc. The sheet 5' can thus be easily and strongly fixed to the side of the cement mortar reinforced.