JPH0745797B2 - Junction structure of waterproof sheet for tunnel - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof sheet joining structure used when constructing a waterproof and cold-resistant tunnel.

Conventional waterproof sheets for tunnels are waterproof to prevent water from seeping out and dripping into the tunnel, forming icicles in cold regions, causing accidents, and causing distortion in the tunnel due to freezing. In addition, cold resistance is required.

In view of the above, various tunnel construction methods have been proposed. Among them, examples shown in FIGS. 7 and 8 are examples in which waterproof and cold resistance are excellent, and the number of construction steps is small and the cost is low.

As shown in the sectional view of FIG. 7, the waterproof sheet 1 of the same example has a waterproof sheet 3 made of a polymer sheet mainly made of rubber or synthetic resin, and has a thick upper surface. The non-woven fabric 2 is entirely adhered and integrated, and a thin non-woven fabric 4 is partially or entirely adhered to the lower surface of the water blocking sheet 3.

Since the waterproof sheet 1 is produced at the factory, the quality uniformity is maintained.

A state in which the waterproof sheet 1 is used in a tunnel is shown in FIG.

10 is a ground excavated into a substantially tunnel shape by a conventional method,
Reference numeral 12 shows the primary lining concrete applied to the surface by a conventional method.

The waterproof sheet 1 is fixed to the surface of the primary lining concrete 12. In this case, the thick non-woven fabric 2 is brought into contact with the surface of the primary lining concrete 12 and fixed with concrete pins or the like.

In this case, the thick non-woven fabric 2 is fixed by concrete pins by stripping the ends of the thick non-woven fabric 2 and the water-proof sheet 3 so that the water blocking sheet 3 is not penetrated by the concrete pins.

When the waterproof sheet 1 is attached to the entire surface of the primary lining concrete 12 in this manner, the foamed heat insulating material 13 of urethane resin is sprayed on the surface of the thin nonwoven fabric 4 of the waterproof sheet 1 to form a heat insulating layer. The heat insulating layer preferably has a thickness of 10 mm to 100 mm.

After the work of spraying the heat insulating material 13 is completed, a secondary lining concrete 14 is applied on the heat insulating material 13 by a conventional method to complete the tunnel.

Here, the thick nonwoven fabric 2 forms a water permeable layer, and the water blocking sheet 3 forms a water blocking layer. In addition, the thin non-woven fabric 4 is a foam insulation material.
An adhesive layer with 13 is formed, and the heat insulating material 13 forms a heat insulating layer.

As shown in FIGS. 9 and 10, heretofore, the method for joining the joints between the waterproof sheets 1 is as follows. First, the end portions 3a and 3b of both the water blocking sheets 3 are brought into contact with each other, and watertightly welded (20 Is a welded portion), and this worship portion is bent on one of the water blocking sheets 3 to perform spot welding (21 is the welded portion).

The joint structure is configured by such a method to prevent water leakage.

Problems to be Solved by the Invention However, in the case of such a joint structure, as shown in FIG. 10, a slack 25 is formed at the bent portion of the contact portion of the water blocking sheet ends 3a and 3b.

The slack 25 may hinder the securing of the winding thickness of the secondary lining concrete 14 in the tunnel.

Means and Actions for Solving Problems The present invention has been made in view of the above points, and an object of the present invention is to prevent the occurrence of sheet slack caused by bending of a water-sealing sheet's worship portion. The point is to provide the joining structure of the sheets.

Therefore, the present invention provides a waterproof sheet for a tunnel in which a thick non-woven fabric is integrally adhered to one surface of a polymer water blocking sheet, and one water blocking sheet joint is preliminarily watertightly superposed on two layers having a uniform thickness. This is a joining structure of a waterproof sheet for a tunnel in which the other waterproof sheet joining portion is superposed on the two-layer waterproof sheet of the waterproof sheet joining portion and welded in a watertight manner.

The water-sealing sheet has a three-layer structure in which one water-stop sheet joint is preliminarily water-tightly superposed on two layers of uniform thickness, and the other water-stop sheet joint is superposed on the surface of the joint. Can be formed flat without causing slack.

Embodiment An embodiment according to the present invention shown in FIGS. 1 to 3 will be described below.

FIG. 2 is a cross-sectional view showing the joint portion of one of the waterproof sheets 1, in which the end portion 3b of the water blocking sheet 3 is previously bent by heat, and the bent portion 3c has no slack and has a uniform thickness. It has a layered structure.

The other waterproof sheet is brought into contact with the waterproof sheet 1 to fix the non-woven fabric 2 to the primary lining concrete 12 with concrete pins 15, and one water-stop sheet end portion 3a of the other is the bent water-stop sheet end portion 3b. Then, as shown in FIG. 3, the two are partially lined and welded.

This welding is made watertight by a self-propelled welding machine. The overlapped portion thus welded is tilted toward the end portion 3b which is bent in advance, and the end portion 3b is spot-welded on the surface of the water blocking sheet 3 to form a joining structure as shown in FIG.

Since the end portion 3b of the water blocking sheet 3 is bent in advance so as to be superposed so as to have a uniform thickness, as shown in FIG. The overlapping part is flat without slack.

Therefore, the winding thickness of the secondary lining concrete 14 is not hindered.

Further, after welding the end portions 3a and 3b of both the water blocking sheets 3, since one end portion 3b has a fold and is in a normal state of collapse, it is extremely necessary to incline the overlapping portion and perform spot welding. It became easier.

Another embodiment will be described with reference to FIGS. 4 to 6.

In this embodiment, the end portion of the folded waterproof sheet 3 of the above embodiment is used.
3b is a separate joining sheet 30, and the material is the same as that of the water blocking sheet 3. As shown in FIG. The area near the edge is welded by wire welding (22 is the welded part).

The other waterproof sheet is brought into contact with such a waterproof sheet, the end portion 3a of the other waterproof sheet 3 is superposed on the joining sheet 30, and both are welded by wire as shown in FIG.

Then, the joining sheet 30 is tilted together with the end portion 3a of the water blocking sheet 3 and spot-welded on the surface of the water blocking sheet 3 to form a joining structure as shown in FIG.

In this embodiment, as in the above-described embodiments, the overlapping portion has no slack and can be made flat, so that there is no problem in the winding thickness of the secondary lining concrete.

Moreover, since the bonding sheet 30 is normally in the collapsed state, it is possible to easily perform spot welding.

EFFECTS OF THE INVENTION The present invention is excellent in waterproofness and cold resistance, and prevents the slack caused by the bending of the waterproof sheet at the joint portion of the waterproof sheet to prevent the concrete of the secondary lining from having a winding thickness. Can be secured.

In the joint portion of the waterproof sheet, the overlapping portion of the waterproof sheets is normally in a state of forming a layer with a uniform thickness, so that the welding work is easy.

[Brief description of drawings]

FIG. 1 is a sectional view showing a joint structure of a waterproof sheet according to an embodiment of the present invention, FIG. 2 is a sectional view showing an end structure of one of the waterproof sheets of the embodiment, and FIG. 4 is a sectional view showing a welded state of an end portion of a water blocking sheet in FIG. 4, FIG. 4 is a sectional view showing a joint structure of a waterproof sheet of another embodiment according to the present invention, and FIG. 5 is an end of one waterproof sheet of the same embodiment. FIG. 6 is a sectional view showing a partial structure, FIG. 6 is a sectional view showing a welded state of an end portion of a water blocking sheet in the same embodiment, FIG. 7 is a sectional view showing a structure of a tunnel waterproof sheet, and FIG. Sectional view showing the internal structure of the tunnel using the waterproof sheet, FIG. 9 is a sectional view showing the welded state of the end of the waterproof sheet in the conventional waterproof sheet joining, and FIG. 10 is the joining structure of the waterproof sheet. FIG. 1 ... Waterproof sheet, 2 ... Nonwoven fabric, 3 ... Waterproof sheet,
4 ... Nonwoven fabric, 10 ... Ground, 12 ... Primary lining concrete, 13 ... Foam insulation, 14 ... Secondary lining concrete,
15 …… Concrete pins, 20,21,22 …… Welded section, 30 ……
Bonding sheet.

Claims (1)

[Claims] 1. A waterproofing sheet for a tunnel in which a thick non-woven fabric is integrally adhered to one surface of a polymeric water blocking sheet to form a waterproof sheet for a tunnel, and one water blocking sheet joint is preliminarily water-tightly superposed on two layers having a uniform thickness. A joining structure for a waterproof sheet for a tunnel, characterized in that the other waterproof sheet joining portion is superposed on the two-layer waterproof sheet of the waterproof sheet joining portion and welded in a watertight manner.