JPH11239771A - Water-barrier sheet laying structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily detect pinholes caused in laying work and to prevent the improvement of the durability of a conductive layer and the lowering of the efficiency of in-site laying work by laying a protective member of the three-layered structure of a protective layer, the conductive layer, and a protective layer in the lower part of a water-barrier sheet. SOLUTION: A water-barrier sheet 1 consisting of a sheet of a synthetic resin such as polyethylene and polyvinyl chloride or a rubber is laid on a protective member 2 laid on a ground to prevent the sheet 1 from being contacted with the ground and broken, The protective member 2 of the three-layered structure of a protective layer 3, a conductive layer 4, and a protective layer 3' is integrated by a needle punch in a production stage, and the protective layers 3, 3' consist of a nonwoven fabric of synthetic fibers such as corrosion resistant polyester fibers. The conductive layer 4 consists of a metal thin film sheet such as aluminum foil and a copper thin film, a nonwoven fabric of synthetic fibers incorporated with a conductive material such as carbon fibers, carbon fibers and polyester fibers, static electricity neutralizing paper of pulp and others, and others. The durability of the conductive layer 4 improves without breaking the layer 4, and the efficiency lowering of protective member bonding work can be prevented by overlapping/bonding the adjacent protective members 3, 3'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to laying of a water-impervious sheet used for easily detecting a pinhole of a water-impervious sheet laid in a final disposal site of waste, a reservoir, a reservoir, and the like. It is about structure.

[0002]

2. Description of the Related Art Conventionally, in order to detect a pinhole or the like that may be generated when a water-impermeable sheet is laid on site, a method of visually checking the entire surface has been adopted. However, this method is simple but has low reliability. Therefore, as shown in FIG. 4, a conductive layer 12 made of a conductive material such as aluminum foil and a protective layer 13 made of a non-woven fabric of polyester are provided on the lower surface of the water shielding sheet 11 as shown in FIG. A method is employed in which an integrated protective member 14 is laid, and a pinhole or the like is detected using a flaw detector utilizing a spark.

[0003]

However, the surface of the conductive layer 12 provided on the surface of the protective member 14 is not protected at all by the conventional method. Therefore, when laying the water-impervious sheet 11 after laying the protective member 14, the water-impervious sheet 11 and the conductive layer 12 rub against each other, and the conductive layer itself may be damaged.

[0004] Further, since the area for laying the impermeable sheet is very large, it is common to use a plurality of protective members 14 instead of one. Therefore, it is necessary to join adjacent protective members. However, when the protection member 14 is used, since a method of overlapping and joining the protection members due to the presence of the conductive layer cannot be adopted, after the ends of the adjacent protection members 14A and 14B are butted together as shown in FIG. A method of joining the surfaces of the conductive layers 12A and 12B using the joining tape 15 must be adopted. However, the joining method is different from the joining method in which the protective members are overlapped and joined, so that when laying on site, there is a problem that the working efficiency is reduced due to inexperience.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and easily detects a pinhole generated when a water-impermeable sheet is laid on site, and improves the durability of a conductive layer and prevents a decrease in work efficiency of laying on-site. Aim.

[0006]

Means for Solving the Problems In order to achieve the above object, the present invention employs the following structure. In other words, in the laying structure of the impermeable sheet laid at the final disposal site of waste, etc., a protective member is laid below the impermeable sheet, and this protective member has a three-layer structure of a protective layer, a conductive layer, and a protective layer. It is characterized by having done.

In particular, it is preferable that the protective member has a structure in which a protective layer, a conductive layer and a protective layer are integrated.

[0008]

According to the above structure, the water impermeable sheet does not directly contact the conductive layer provided on the protection member. Therefore, when laying the impermeable sheet, the impermeable sheet and the conductive layer are not rubbed.

Further, since the protective member has a three-layer structure of a protective layer, a conductive layer, and a protective layer, even when adjacent protective members are joined to each other, the protective member is provided above and below the conductive layer. It is possible to adopt a method of overlapping and joining the protective layer.

Since the protective member has a structure in which the protective layer, the conductive layer and the protective layer are integrated, the protective layer, the conductive layer and the protective layer can be simultaneously laid when the protective member is laid. Become. In addition, since the conductive layer and the protective layer are integrated, the position of the conductive layer does not shift after the protective member is laid.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of the present invention. 1 to 3 show an embodiment of a structure for laying a seepage control sheet.

In the laying structure shown in FIG. 1, a protective member 2 is first laid on the ground to prevent the waterproof sheet from touching the ground and being damaged, and the waterproof sheet 1 is placed on the protective member 2.
Is laid. The water-impervious sheet 1 is made of a conventionally used synthetic resin sheet such as polyethylene, polyvinyl chloride, polypropylene or the like, or a rubber sheet.
The protective member 2 has a three-layer structure of a protective layer 3, a conductive layer 4, and a protective layer 3 ', and these three layers are integrated by a needle punch at the stage of being manufactured at a factory. The protective layers 3 and 3 ′ provided on the protective member 2 are made of a nonwoven fabric made of a synthetic fiber having corrosion resistance, for example, polyester or polypropylene, and the conductive layer 4 is made of a metal such as a thin film made of aluminum foil or copper. It is composed of a thin film sheet, a nonwoven fabric mixed with carbon fibers, a nonwoven fabric made of synthetic fibers mixed with a conductive material, a carbon fiber and polyester fiber, a neutralized paper made of pulp, and the like.

The entire thickness of the protection member 2 shown in FIG.
The thickness of the protective layer 3 is 1 to 5 mm, the thickness of the protective layer 3 ′ is 5 to 15 mm, and the thickness of the conductive layer 4 is 0.05 to 0.2 from the viewpoints of easy generation of sparks and improvement of the durability of the conductive layer 4. mm is desirable. Further, in order to clarify the upper and lower portions of the protective member 2, the protective layer 3 and the protective layer 3 'may be colored differently.

FIG. 2 shows a conceptual diagram of pinhole detection using the flaw detector 5 in the laying structure shown in FIG. In this case, when the inspection electrode brush 6 passes near the upper part of the pinhole 7 generated in the water shielding sheet 1, a spark 8 is generated between the inspection electrode brush 6 and the conductive layer 4, and the flaw detector 5 is stopped. The system sounds a buzzer to notify the presence of a pinhole.

FIG. 3 shows a method of joining adjacent protection members 2A and 2B when laying on the site. In this case, the protective members 2A and 2B can be joined by superposing the terminals and then fusing the joint with hot air.

[0016]

According to the water-impervious sheet laying structure of the present invention, since the conductive layer does not rub against the water-impervious sheet, the conductive layer itself is not damaged and the durability is improved. Also,
Since a method in which adjacent protection members are overlapped and joined can be adopted, the working efficiency at the time of joining the protection members does not decrease.

Further, since the protective member has a structure in which the protective layer, the conductive layer, and the protective layer are integrated, the protective layer, the conductive layer, and the protective layer can be laid at the same time. The time required for laying members can be reduced. Also,
Since the conductive layer and the protective layer are integrated, the conductive layer does not shift, and the conductive layer can be easily installed at a predetermined position, so that the accuracy of the pinhole inspection increases.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a conceptual diagram illustrating a method of detecting a pinhole.

FIG. 3 is a cross-sectional view illustrating a bonding method of the protection member of the present invention.

FIG. 4 is a cross-sectional view showing a conventional waterproof sheet laying structure.

FIG. 5 is a cross-sectional view showing a joining method of a protective member in a conventional waterproof sheet laying structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waterproof sheet 2 Protective member 3 Protective layer 4 Conductive layer 5 Flaw detector 6 Inspection electrode brush 7 Pinhole 8 Spark

Claims (2)

[Claims] 1. A water-impervious sheet and a water-impervious sheet laying structure in which a protective member is laid below the water-impervious sheet, wherein the protective member has a three-layer structure of a protective layer, a conductive layer, and a protective layer. Characteristic laying structure of impermeable sheet 2. The waterproofing sheet laying structure according to claim 1, wherein said protective member has a structure in which a protective layer, a conductive layer, and a protective layer are integrated.