When laying the tunnel waterproofing board, it is required to strictly follow the following procedures:
1. The protruding parts such as steel mesh should be cut first and then smoothed with mortar ash.
2. When there are protruding pipes, cut them off and smooth them with mortar.
3. When there is a protruding part of the anchor rod of the tunnel waterproof plate, the top of the screw head is reserved 5mm and cut off, and then treated with a plastic cap.
4. Make the surface smooth and smooth by spraying concrete, and the amount of unevenness should not exceed ±5cm.
5. On the concrete surface, 350g/m2 geotextile should be pasted with a liner first, and when there is a drainage board, it should be pasted at the same time, and then the cement nails should be nailed with a nail gun for anchoring, and the length of the cement nails should not be less than 50mm. The average vault is 3-4 points/m2, and the side wall is 2-3 points/m2.
6. In order to prevent the cement slurry from infiltrating into the geotextile, first lay the geotextile and then lay the tunnel waterproof board.
7. When laying the waterproof board, use a manual special welder to hot-melt on the liner, and the bonding and peeling strength of the two should not be less than the tensile strength of the waterproof board.
8. The special welding device is used for hot-melt bonding between the waterproof boards, the joint part shall not be less than 10cm, and the bonding peeling strength shall not be less than 80% of the tensile strength of the parent body.
9. The distance between the circumferential bond of the tunnel waterproofing board and the lining joint shall not be less than 1.0m. Before the waterproofing layer is laid, the waterproofing board shall not be tightened, and the surface of the board shall be closely attached to the surface of the shotcrete and shall not be pulled apart.
Post time: Aug-19-2022