JP3033402B2 - 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 in a joint portion of a water-impermeable sheet, and more particularly to a method for detecting a defective portion in a joint portion of a double-layer water-impermeable sheet composed of an upper sheet and a lower layer sheet. The present invention relates to a method for detecting a defective portion of a joint portion of a water impermeable 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. Also, golf course water hazards, simple reservoirs,
On the bottom of the facility that stores water in depressions such as reservoirs and pools,
In order to prevent the leakage of stored water, impermeable sheets will be laid in the same way as for waste disposal sites. Furthermore, in underground structures, etc.,
In some cases, a water-blocking sheet is laid around the structure to prevent groundwater or the like from leaking into the structure.

[0003] In order to more reliably prevent leakage of sewage and stored water by such a water-blocking sheet, conventionally,
A water-blocking sheet having a double structure, that is, a water-blocking sheet comprising an upper layer sheet and a lower layer sheet has been proposed, and in a planar space formed by the upper layer sheet and the lower layer sheet, a ventilation mat, a nonwoven fabric, or the like is provided. There are also proposals in which various members are further provided.

[0004] In addition, it is difficult to cover these water-impervious sheets at once with a single sheet of water-impervious sheet covering the bottom of a storage facility such as a waste disposal site or a reservoir having a large area or the periphery of a structure. Therefore, at the site, the divided parts are joined and integrated at the site by welding or crimping via an adhesive, etc., so that the impermeable sheet can be attached to the bottom or structure of a waste disposal site or storage facility. Lay the entire area around the object.

[0005]

However, in the method of joining and integrating the plurality of divided water-impervious sheets on site, there may be a case where a joining failure occurs. There was a problem that it could leak.

Further, various methods have been proposed to detect such a defective portion. However, it is difficult to detect the defective portion simply and quickly on site, and it is difficult to detect the defective portion with high accuracy. There was a problem.

Therefore, the present invention has been made in view of such a conventional problem, and a method for detecting a defective portion of a joint portion of a water-impermeable sheet, which can perform a detection operation simply, quickly, and easily on site. It is intended to provide.

Another object of the present invention is to provide a method for detecting a defective portion in a joint portion of a water-impermeable sheet, which can accurately specify a defective portion in the joint portion.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and the gist of the present invention is to provide a method for detecting a defective portion in a joint portion of a double-layer water-impermeable sheet comprising an upper sheet and a lower sheet. What is claimed is: 1. A method for detecting a defective portion in a joint portion of a water-impervious sheet for detecting, wherein the planar space formed by the upper sheet and the lower sheet is suctioned or pressurized, and the planar space after the suction or pressurization is applied. A method for detecting a defective portion of a water-impervious sheet joint characterized by detecting the presence or absence of a defective portion of the joint by detecting a change in internal pressure.

Another aspect of the present invention is a method for detecting a defective portion in a joint portion of a water-impermeable sheet for detecting a defective portion in a joint portion of a double-structured water-impermeable sheet including an upper sheet and a lower layer sheet. Attaching a thin sheet to the upper surface of the water-impervious sheet by covering the joining portion for a predetermined length in the direction of extension thereof, and suctioning or pressing the planar space formed by the upper layer sheet and the lower layer sheet, Defective portion of the joint portion of the impermeable sheet, wherein the presence or absence of the deficient portion in the joint portion is detected by visually checking deformation of the thin sheet caused by air flowing through the deficient portion generated in the joint portion. In the detection method.

Another aspect of the present invention is a method for detecting a defective portion in a joint portion of a water-impermeable sheet for detecting a defective portion in a joint portion of a water-impermeable sheet having a double structure including an upper layer sheet and a lower layer sheet. The joint is covered with a predetermined length in an extending direction of the joint, and an air-tight adhesive tape is attached to an upper surface of the waterproof sheet, and an end face of the waterproof sheet at the joint is extended along the end face. A closed ventilation space to be formed is formed inside the airtight adhesive tape, and a planar space formed by the upper layer sheet and the lower layer sheet is suctioned or pressurized, and the air flowing through the defective portion generated at the joint is removed. By detecting the fluctuation of the pressure in the closed ventilation space by the sound generated from the whistle member attached to the airtight adhesive tape, it is possible to detect the presence or absence of a defective portion in the joint. In chipped portions detection method of the joint of water shield sheet according to symptoms.

In the detection method using the thin sheet and the detection method using the airtight adhesive tape, when a defective portion of the joint is detected, the joint is covered with the thin sheet or the airtight adhesive tape. It is preferable to detect the presence or absence of a missing portion while sequentially shortening the length, and specify the position of the missing portion.

[0013]

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, for example, formed by excavating a vast site in a mountainous region or the like in a concave shape, and laying a double-structured water-blocking sheet 11 on the bottom surface of the concave portion into which the waste H is charged. A sand mat 14 as a protection mat is laminated above the above, and thereafter, the waste H is dumped and buried above these.

As shown in FIG. 2, the waterproof sheet 11 comprises an upper waterproof sheet 12 and a lower waterproof sheet 13 made of, for example, a soft synthetic resin or rubber-based sheet member. Water sheet 12 and lower layer impermeable sheet 1
A ventilation mat 16 made of, for example, a nonwoven fabric or the like is interposed in the planar space 15 formed therebetween. The ventilation mat 16 includes the upper waterproof sheet 12 and the lower waterproof sheet 1.
3 to prevent the protrusions and the like from penetrating both the upper and lower sheets when there is a protrusion or the like in the waste H, and when detecting a defective portion of a joint portion to be described later, the upper and lower sheets of the upper and lower sheets are detected. It has a function of preventing airtightness and securing an air passage. Further, the planar space 15 is divided into a large number of sealed spaces of a predetermined size by joining the upper water-permeable sheet 12 and the lower water-permeable sheet 13 at predetermined locations. Further, the upper water-impervious sheet 12 and the lower water-impervious sheet 13 are formed as a single large waste disposal site 10.
Because it is difficult to cover the entire bottom surface area at once, it is difficult to apply a unit size impermeable sheet of a predetermined size suitable for construction at the work site by, for example, welding or crimping with an adhesive. The parts are joined to each other as joint parts 17 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 of this embodiment is particularly used for detecting a defective portion of the joint 17 of the upper water-impervious sheet 12. That is, in order to perform such a detection method, first, as shown in FIG.
A thin sheet 18 made of a synthetic resin such as vinyl, for example, is attached on the upper surface of the water-impervious sheet 11 so as to cover several tens of meters by bonding the four sides thereof. A pressure-resistant hose 19 is inserted into the end of the planar space 15 formed between the upper water-impervious sheet 12 and the lower water-impervious sheet 13 while hermetically sealing the periphery thereof. This pressure-resistant hose 19 is connected to a vacuum pump 20 or a compressor 21 as shown in FIG.
And a vacuum gauge 22 is attached to the surface space 15 while vacuum suction or air pressure injection is performed.

After these mounting operations are completed, the vacuum pump 20 or the compressor 21 is operated next.
The planar space 15 is set in a negative pressure state or a pressurized state.
That is, when the vacuum pump 20 is used, the planar space 1
5, the compressor 21
When air is used, the air is fed into the planar space 15 so as to be in each pressure state, and is left for a while in this state to change the thickness of the thin sheet 18 attached over the joint 17. Observe. Then, the thin sheet 1 due to air leaking through the defective portion of the joint portion 17
By checking the close contact or swelling of the joint 8 by silent observation, it is possible to easily detect the presence or absence of a defective portion in the joint 17. The degree of closeness or swelling of the thin sheet 18 can also be used to determine the airtightness, that is, the degree of a defect.

Also, by observing a change in the pressure state in the planar space 15 with a pressure gauge 22 attached to the pressure-resistant hose 19, it is possible to include a region other than the portion covered by the thin sheet 18. In addition, the presence or absence of a defective portion in the joint 17 can be easily confirmed.

When the presence of a defect is confirmed by observing the thin sheet 18, the same detection operation is continuously performed while sequentially reducing the length of the thin sheet 18 covering the joint 17. That is, since the thin sheet 18 can be easily attached and detached, it is possible to confirm the presence or absence of a pressure change while sequentially narrowing the area for performing the detecting operation, and finally, the joining section 1
7, the position where the defective portion exists can be easily and accurately specified.

FIG. 5 shows another embodiment of the method for detecting a defective portion of a joint portion of a waterproof sheet according to the present invention. That is, in this embodiment, instead of the thin sheet 18 in the above-described embodiment, the joint 17 is covered by a predetermined length, and is disposed on the end face of the joint 17, that is, the end face of the upper water-impervious sheet 12 located on the upper side. The airtight adhesive tape 24 is adhered to the upper surface of the upper water-impervious sheet 12 while the flexible ventilation member 23 made of, for example, perforated plastic or the like is wound. Therefore, a ventilation space 25 extending along the end face is formed by the flexible ventilation member 23 on the end face of the joint 17. In addition, the airtight adhesive tape 24 includes:
A whistle member 26 with a relief valve is previously attached to a predetermined location, and thus communicates with the ventilation space when the airtight adhesive tape 24 is attached. Then, both ends of the ventilation space are sealed with an airtight seal or the like to form a sealed ventilation space, and the vacuum pump 20 or the compressor 21 is operated to operate the planar space as in the case of the above-described embodiment. When the pressure 15 is set to a negative pressure state or a pressurized state, air leaking from the planar space 15 to the ventilation space 25 through the defective portion of the joint portion 17 is generated by the whistle member 26.
This makes it possible to easily detect the presence or absence of a defect in the joint 17.

If the presence of a defect is confirmed, the same detection operation is performed by successively shortening the length of the joint 17 with the hermetic adhesive tape 24, thereby performing the above-described operation. As in the case of the example, it is possible to easily and accurately specify the position of the joint 17 where the defective portion exists.

In each of the above embodiments, the joint 17
The thin sheet 18 or the air-tight adhesive tape 24 that covers and adheres to the upper surface of the upper water-impervious sheet 12 has, for example, an adhesive on the entire lower surface thereof, as well as a portion directly adhered to the upper water-impervious sheet 12. It is also possible to use one having an adhesive only on its lower surface side.

In each of the above embodiments, a case has been described in which a water barrier sheet is laid at a waste disposal site. However, the present invention is not limited to these, and water hazards at golf courses, simple reservoirs, The present invention can also be applied to a case where a water-impervious sheet is laid on the bottom of a facility that stores water in a depression such as a reservoir or a pool, or a case where a water-impervious sheet is laid to cover the periphery of an underground structure.

[0023]

As described above in detail, according to the method for detecting a defective portion of a joint portion of a waterproof sheet according to the present invention, a planar space formed by an upper sheet and a lower sheet is pressurized or negative. By detecting the pressure state and detecting a change in the pressure state, or detecting the air leaking from the joint due to the pressure state, the detection operation can be performed simply, quickly and easily at the site.

Further, if the detecting operation is continuously performed while sequentially reducing the length covering the joining portion with a thin sheet or an airtight adhesive tape, finally, the position where the defective portion exists in the joining portion can be accurately detected. Can be identified.

[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.

FIG. 5 is a cross-sectional view showing another embodiment of the method for detecting a defective portion of a joint portion of a water impermeable sheet according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 waste disposal site 11 water-blocking sheet 12 lower layer water-blocking sheet 13 upper layer water-blocking sheet 15 planar space 16 ventilation mat 17 joint 18 thin sheet 19 pressure-resistant hose 23 flexible ventilation member 24 airtight adhesive tape 25 ventilation space 26 Whistle material

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Masao Kuroiwa 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Head Office (56) References JP-A-64-25024 (JP, A) JP-A Sho 63-182134 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 3/00-3/40 B09B 1/00

Claims (4)

(57) [Claims] 1. A method for detecting a defective portion in a joint portion of a water impermeable sheet for detecting a defective portion in a joint portion of a water impermeable sheet having a double structure including an upper sheet and a lower layer sheet,
By suctioning or pressurizing the planar space formed by the upper layer sheet and the lower layer sheet and detecting a change in pressure in the planar space after the suction or pressurization, the presence or absence of a defective portion of the joint portion A method for detecting a defective portion of a joint portion of a water-impervious sheet, characterized by detecting a defect. 2. A method for detecting a defective portion at a joint portion of a water-impermeable sheet for detecting a defective portion at a joint portion of a water-impermeable sheet having a double structure including an upper layer sheet and a lower layer sheet,
The joining portion is covered for a predetermined length in the extending direction of the joining portion, a thin sheet is adhered to the upper surface of the water-impervious sheet, and a planar space formed by the upper layer sheet and the lower layer sheet is suctioned or pressurized, and A method for detecting a defective portion in a joint portion of a water impermeable sheet, wherein the presence or absence of a defective portion in the joint portion is detected by visually checking deformation of the thin sheet caused by air flowing through the generated defective portion. 3. A method for detecting a defective portion in a joint portion of a water-impermeable sheet for detecting a defective portion in a joint portion of a water-impermeable sheet having a double structure including an upper layer sheet and a lower layer sheet,
The joint is covered with a predetermined length in the extension direction of the joint, and an airtight adhesive tape is attached to the upper surface of the water-impervious sheet. A space is formed inside the hermetic adhesive tape, a planar space formed by the upper sheet and the lower sheet is suctioned or pressurized, and a pre-sealed ventilation space by air flowing through a defective portion generated at the joint portion. Detecting the presence or absence of a defective portion in the joint by detecting a change in pressure in the joint by a sound generated from a whistle member attached to the airtight adhesive tape. Location detection method. 4. When a defective portion of the joint is detected, the length of covering the joint with the thin sheet or the airtight adhesive tape is sequentially reduced, and the presence or absence of the defective portion is continuously detected to detect the defect. The method according to claim 2 or 3, wherein the position of the location is specified.