JP3097790B2 - Detecting method of defective part of joint part of impermeable sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting a defective portion of a joint of a waterproof sheet, and more particularly to a joint of a waterproof sheet laid at a waste disposal site to prevent leakage of wastewater generated from waste. The present invention relates to a method for detecting a defective portion of a joint portion of a water-impervious sheet for detecting a defective portion in a sheet.

[0002]

2. Description of the Related Art For example, in a landfill type waste disposal site that dumps industrial waste and general waste, it is necessary to prevent wastewater leaking from the disposal site from penetrating underground and causing environmental pollution. It is obliged to implement a seepage control on the bottom of the building. As such a water shield, certainty, safety,
From the viewpoints of workability, economy and the like, a method of laying a soft synthetic resin-based or rubber-based water impermeable sheet has been adopted.

[0003] Since it is difficult in construction to cover the bottom surface of a waste disposal site having a large area with a single water-impervious sheet at a time, these water-impervious sheets are divided into a plurality of sheets. In the above, the ends of the waste disposal site are laid so as to cover the entire bottom surface of the waste disposal site by joining and integrating the ends thereof by welding or pressure bonding via an adhesive.

[0004]

However, the above-mentioned method of joining and integrating the plurality of divided water-impervious sheets on site may cause defective joints, and contaminated water leaks out from a defective portion due to the defective joints. There was a problem of fear.

Further, various methods have been proposed to detect such a defective portion. However, these methods have a problem that the defective portion cannot be easily and quickly detected and specified on site.

Accordingly, the present invention has been made in view of such a conventional problem, and it is possible to easily, quickly and easily perform a detection operation on site, and to accurately detect and specify a defective portion. It is an object of the present invention to provide a method for detecting a defective portion of a joint portion of a waterproof sheet that can be performed.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and a gist of the invention is to provide a water-impervious sheet laid at a waste disposal site to prevent leakage of sewage generated from waste. The method for detecting a defective portion of a joint portion of a water impermeable sheet for detecting a defective portion in a joint portion,
An airtight adhesive tape is attached to the upper surface of the water-impervious sheet so as to cover the joint portion for a predetermined length in the extension direction of the joint portion, and the joint portion may be disposed along the end surface on the end surface. A sealed ventilation space is formed by winding the flexible ventilation member with the airtight adhesive tape, and the sealed ventilation space is sucked or pressurized, and a change in pressure in the sealed ventilation space after the suction or pressurization is detected. Thus, the presence or absence of a missing portion of the joint at the portion covered by the airtight adhesive tape is detected, and if the missing portion of the joint is detected,
In this case, the airtight adhesive tape covers the joint.
And reducing the length of the flexible ventilation member sequentially.
The presence or absence of the missing part is detected and the position of the missing part is identified.
In chipped portions detection method of the joint of water shield sheet which is characterized by a constant.

[0008]

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of a waste disposal site 10 in which a water-impervious sheet 11 is laid on the entire bottom surface while employing the method for detecting a defective portion of a joint part of a water-impervious sheet according to the present invention. That is, the waste disposal site 10 is formed by, for example, excavating a large site in a mountainous region or the like in a concave shape.
1 is laid, and a sand mat 12 as a protective mat is laminated thereon, and thereafter, waste H is dumped and buried above these.

Here, the impermeable sheet 11 is made of, for example, a soft synthetic resin or rubber-based sheet member, but as a single sheet, covers the entire bottom surface area of the vast waste disposal site 10 at one time. Since it is difficult to cover the construction, at the work site, as shown in FIG. 2, a unit size impermeable sheet having a predetermined size suitable for construction is formed by, for example, welding or crimping via an adhesive. The ends are overlapped and joined to each other as a joining portion 13, and are integrated into a size that can cover the bottom surface of the waste disposal site 10.

The method for detecting a defective portion in this embodiment is used to detect a defective portion in the joint 13. That is, in order to perform such a detection method, as shown in FIG. 3, first, the joint 13 is covered with a predetermined length, for example, about several meters to several tens of meters along the extension direction of the joint 13, and the end face of the joint 13 is That is, the airtight adhesive tape 1 is wound while the flexible ventilation member 15 made of, for example, perforated plastic or the like disposed on the end face of the water impermeable sheet 11 located on the upper side is involved.
4 is stuck on the upper surface of the impermeable sheet 11. Therefore, on the end face of the joint portion 13, the flexible ventilation member 15
A ventilation space 16 extending along the end face is formed.
The variable via a gas-tight seal, such as the both end portions of the ventilation space 16
With sealed except for the ends of FLEXIBLE ventilation member 15, as shown in FIG. 4, the one end portion, pressure hose for conducting vacuum suction or pressurized air injection a sealed ventilation space 16 17 is inserted. The pressure hose 17
Is connected to a vacuum pump 18 or a compressor 19, and is provided with a pressure gauge 20 in the middle thereof.

When these mounting operations are completed, the ventilation space 16 is then brought into a negative pressure state or a pressurized state using the vacuum pump 18 or the compressor 19. In other words, when the vacuum pump 18 is used, the air in the closed ventilation space 16 is sucked, and when the compressor 19 is used, the air is supplied into the ventilation space 16 so that the respective pressure states are changed. Along with
This state is left for a while, and a change in pressure is observed by the pressure gauge 20. Then, by detecting a decrease in the negative pressure or the pressing force, the airtight adhesive tape 1 is detected.
It turns out that there is a defective portion in any part of the joint portion 13 covered by 4.

When the pressure gauge 20 detects a decrease in the negative pressure or the applied pressure, the length of the airtight adhesive tape 14 covering the joining portion 13 and the length of the flexible air wrapped around the airtight adhesive tape 14 are determined. While the length of the member 15 is sequentially shortened, the same detection operation is continuously performed. That is, the airtight adhesive tape 14, the flexible ventilation member 1
5, and the pressure-resistant hose 17 can be easily attached and detached.
By confirming the presence / absence of a pressure change, it is possible to finally accurately specify the position where the defective portion exists in the joint portion 13.

[0014]

As described above in detail, according to the method for detecting a defective portion of a joint portion of a water-impervious sheet according to the present invention, the joint portion is covered for a predetermined length while a flexible ventilation member is involved, and an airtight adhesive tape is provided. By applying a simple structure that aspirates or pressurizes the sealed ventilation space formed on the end face of the joint by attaching the sealing member, and detects fluctuations in the pressure state of the sealing ventilation space, the defective portion can be easily and quickly placed on site. Can be detected.

Further, by sequentially reducing the length of the joint portion covered with the airtight adhesive tape and the length of the flexible ventilation member wound around the joint portion while continuously checking the presence or absence of a defective portion, the defective portion can be reduced. The existing position can be specified with high accuracy.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a waste disposal site on which a water-impermeable sheet is laid using the method for detecting a defective portion of a joint portion of a water-impermeable sheet according to the present invention.

FIG. 2 is an enlarged view of a main part showing a laying state of a seepage control sheet.

FIG. 3 is a cross-sectional view showing one embodiment of a method for detecting a defective portion of a joint portion of a water-impervious sheet according to the present invention.

FIG. 4 is a plan view of FIG. 3 as viewed from above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Waste disposal site 11 Waterproof sheet 13 Joint 14 Airtight adhesive tape 15 Flexible ventilation member 16 Ventilation space 17 Pressure-resistant hose 18 Vacuum pump 19 Compressor 20 Pressure gauge

(72) Inventor Shuichi Sakamoto 2-3-3 Kandajicho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Head Office (72) Inventor Takeshi Kawaguchi 5-407-7 Makuhari-cho Hanamigawa-ku, Chiba-shi, Chiba (56) References JP-A-4-80452 (JP, A) JP-A-4-184132 (JP, A) JP-A-2-14050 (JP, U) JP-A 59-100244 (JP, U) JP-A 52−11064 (JP, U)

Claims (1)

(57) [Claims] 1. A method for detecting a defective portion at a joint of a waterproof sheet for detecting a defective portion at a joint of a waterproof sheet laid at a waste disposal site to prevent leakage of wastewater generated from waste. The joint is covered with a predetermined length in the extension direction of the joint, and an air-tight adhesive tape is attached to an upper surface of the water-impermeable sheet, and an end face of the joint is arranged along the end face. A sealed ventilation space is formed by winding the provided flexible ventilation member with the airtight adhesive tape, and the sealed ventilation space is sucked or pressurized, and the pressure in the sealed ventilation space after the suction or pressurization is changed. Is detected, the presence or absence of a missing portion of the joint at the portion covered by the airtight adhesive tape is detected.
In this case, the airtight adhesive tape covers the joint.
And reducing the length of the flexible ventilation member sequentially.
The presence or absence of the missing part is detected and the position of the missing part is identified.
A method for detecting a defective portion of a joint portion of a seepage control sheet, comprising: