JPH06294699A - Method and apparatus for detecting damage at joint of water shielding sheet - Google Patents

Abstract

PURPOSE:To provide a method and an apparatus for detecting a damage at the joint of a water shielding sheet which make possible quick and easy detection work at a site and highly accurate detection even of a microdamage. CONSTITUTION:A damage point detector 18 is installed on the upper face of an upper layer water shielding sheet 12 while covering a joint 17 and pressed tightly against the upper layer water shielding sheet 12 using a handle 23 thus forming a closed space 22 along the joint 17. A planar space 15 defined between the upper and lower water shielding sheets 12, 13 is then evacuated. When any damage is present at the joint 17, outer air is sucked through a whistle member 21, a hollow rod 20, and the closed space 22 into the planar space 15. At that time, the whistle member 21 produces a sound.

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 defect in a joint portion of a waterproof sheet and an apparatus for detecting a defect used in the method, and more particularly to a waterproof sheet having a double structure composed of an upper sheet and a lower sheet. The present invention relates to a method for detecting a defect in a joint of a water-blocking sheet for detecting a defect in the joint, and a defect detecting device used in the method.

[0002]

2. Description of the Related Art For example, in a landfill type waste disposal site for dumping industrial waste and general waste, in order to prevent sewage leaking from the disposal site from infiltrating underground and causing environmental pollution, It is obligatory to carry out a seepage control work on the bottom of the. As such a water barrier, certainty, safety,
From the viewpoint of workability and economy, a method of laying a soft synthetic resin-based or rubber-based waterproof sheet is adopted. Also, on the bottom of facilities that store water in recesses such as water hazards in golf courses, simple reservoirs, ponds or pools, in order to prevent the leakage of stored water, a water blocking sheet is laid in the same way as at the waste disposal site. To be done. Further, in an underground structure or the like, a water blocking sheet may be laid around the structure to prevent groundwater or the like from leaking into the structure.

In order to prevent leakage of sewage, stored water, etc. with such a water-blocking sheet more reliably, it has been necessary to
A water-impermeable sheet having a double structure, that is, a water-impermeable sheet composed of an upper-layer sheet and a lower-layer sheet has been proposed, and various kinds of ventilation mats, non-woven fabrics, etc. are provided in a planar space formed by the upper-layer sheet and the lower-layer sheet. It is also proposed to further dispose the above member.

In addition, it is difficult in construction to cover the bottom surface of a storage facility such as a waste disposal site or a reservoir having a vast area or the periphery of a structure with a single water shield sheet at a time. Therefore, the water-blocking sheet is divided into multiple pieces, and the ends are joined and integrated at the site by welding or pressure bonding with an adhesive, so that the water-blocking sheet is placed on the bottom surface of the waste disposal site or storage facility or the structure. It is laid so as to cover the entire area around.

[0005]

However, in the method of joining and integrating the above-mentioned water-impermeable sheets divided into a plurality of pieces on site, a joint failure may occur, and sewage, stored water, etc. may be generated from the defective portion due to this joint failure. There was a problem that it could leak.

Various methods have been proposed to detect such a defect portion, but the detection work cannot be performed easily and quickly at the site, and a pinhole-like small defect portion can be detected accurately. There was a problem that it was difficult to do.

Therefore, the present invention has been made by paying attention to such conventional problems, and it is possible to perform detection work easily, quickly and easily on site, and to detect even a minute defective portion with high accuracy. It is an object of the present invention to provide a method for detecting a defective portion of a joint portion of a water-impervious sheet and a defective portion detecting device used in the method.

[0008]

The present invention has been made in order to achieve the above-mentioned object, and its gist is to eliminate a defective portion at a joint portion of a double-layer water-impervious sheet composed of an upper layer sheet and a lower layer sheet. A method for detecting a defective portion of a joint portion of a water-impervious sheet for detecting, wherein a planar space formed by the upper layer sheet and the lower layer sheet is vacuum-sucked, and a surface is formed via the defective portion generated in the joint portion. In the method for detecting a defective portion of a joint portion of a water-blocking sheet, the defective portion is detected by detecting air flowing into the space as a sound.

Another aspect of the present invention is a detection device used in the method for detecting a defect, wherein the tip is extended along the joint, and the tip is sandwiched between the joints on both sides thereof. A leg portion that forms a box-shaped closed space together with the water-blocking sheet on the upper surface of the water-blocking sheet by closely contacting with the water-blocking sheet, and a whistle that is erected from the leg portion and generates a sound by sucking air from the outside. It is a hollow portion detection device characterized by comprising a hollow rod provided with a member.

Still another aspect of the present invention is a detection device used in the method for detecting a defect, wherein the tip is extended along the joint portion and the tip is sandwiched between the joint portions. A leg that forms a box-shaped closed space together with the water-blocking sheet on the upper surface of the water-blocking sheet by closely contacting with both sides, and a hollow rod that stands upright from the leg and has a stethoscope and an air opening. The defect detecting device is characterized by comprising:

[0011]

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 adopting a method and a device for detecting a defective portion of a joint of a water impervious sheet according to the present invention. . That is, the waste disposal site 10
For example, a vast site in a mountainous area is excavated and formed in a concave shape. A double-layered waterproof sheet 11 is laid on the bottom surface of the recess into which waste H is put, and a protective mat is provided above it. The sand mat 14 as described above is laminated, and thereafter the waste H is dumped and landfilled above them.

As shown in the enlarged view of FIG. 2, the water-impervious sheet 11 is composed of an upper-layer water-impermeable sheet 12 and a lower-layer water-impermeable sheet 13 which are made of, for example, a soft synthetic resin or rubber type sheet member. A ventilation mat 16 made of, for example, a non-woven fabric is interposed in the planar space 15 formed between the upper water-impervious sheet 12 and the lower water-impervious sheet 13. The ventilation mat 16 maintains the space between the upper water-impervious sheet 12 and the lower water-impervious sheet 13 to prevent the waste H from penetrating both upper and lower sheets when there is a protrusion or the like. When detecting a defective portion of a joint portion, which will be described later, it has a function of preventing the upper and lower sheets from adhering to each other and ensuring an air passage. In addition, the planar space 15
Is joined to the upper-layer waterproof sheet 12 and the lower-layer waterproof sheet 13 at a predetermined location, thereby being divided into a large number of closed spaces having a predetermined size. Furthermore, the upper water-blocking sheet 12
Since the lower water-impervious sheet 13 and the lower water-impervious sheet 13 cannot cover the entire bottom surface area of the vast waste disposal site 10 at a time, a unit water impervious sheet of a predetermined size suitable for construction at the work site. The ends are joined to each other with the end portions being the joint portions 17 by, for example, welding or pressure bonding using an adhesive, and are integrated into a size capable of covering the bottom surface of the waste disposal site 10.

The defect detecting method of this embodiment is particularly used to detect a defect of the joint portion 17 of the upper water shield sheet 12. That is, in order to carry out such a detection method, as shown in FIG.
On the upper surface of 2, the defect detection device 18 covering the joint 17
Set up.

The defect detecting device 18 has an opening at the bottom and the upper water-blocking sheet 12 in its installed state.
Box-shaped leg 1 of triangular cross section extending along the joint 17 of
9 and a hollow rod 20 extending upward from the box-shaped leg portion 19. An airtight rubber 24 is attached to the bottom end of the box-shaped leg portion 19, and
Partitioning plates 25 (see FIG. 4) are attached to both ends of the extending direction along the joint portion 17 at right angles to the extending direction at predetermined intervals suitable for the work, and therefore, the defect detecting device 18 is installed. When installed on the upper surface of the upper water-impervious sheet 12, the box-shaped leg portion 19 forms a closed space 22 together with the upper water-impervious sheet 12. The hollow rod 20 communicates with the closed space 22, and the whistle member 2 is provided at the tip thereof.
1 is attached, and the pressing handle 23 projects from the side surface.

To carry out the defect detection method of this embodiment, for example, the defect detection device 18 is first installed on the upper surface of the upper water-impervious sheet 12 while covering the joint portion 17, and the pressing handle 23 is used. And press it against the upper layer water-impervious sheet 12 and bring them into close contact with each other to form a closed space 22 along the joint portion 17. Next, the upper layer waterproof sheet 1
The planar space 15 between the lower layer 2 and the lower water-impervious sheet 13 is vacuumed.

That is, when there is a defective portion in the joint portion 17, the external air is drawn into the planar space 15 through the whistle member 21, the hollow rod 20 and the closed space 22 by the vacuum suction. At this time, the whistle member 21 makes a sound. The vacuum suction in the planar space 15 can be easily performed by a vacuum hose, a vacuum pump or the like installed in communication with the vacuum.

The installation of the defect detecting device 18 and the vacuum suction of the planar space 15 are performed as shown in FIG.
It is possible to easily perform detection and identification of the defective portion of the joint 17 depending on whether or not the whistle sound is generated at each installation location while repeating the sequence along the joint 17. It should be noted that it is also possible to judge the state of loss by the pitch of the whistle.

FIG. 5 shows another embodiment of the detecting device used in the defect detecting method of the present invention. That is, the defect detection device 30 has a configuration substantially similar to that of the defect detection device 18 of FIG. 3, except that a stethoscope 31 is attached to the upper end of the hollow rod 20 and an air opening 32 is provided. It is a thing. In this defect location detection device 30, the air space 32, the hollow rod 20, and the closed space 2 are obtained by vacuum suction of the planar space 15.
By listening to the sound of the air passing through the defective portion of the joining portion 17 via 2 and drawn into the planar space 15 when passing through the defective portion with the stethoscope 31, the air shown in FIG.
Like the defect detection device 18, the detection and identification of the defect can be easily performed, and the defect detection device 30 can easily detect a pinhole-like small defect.

The present invention is not limited to the above-described embodiment. For example, as means for detecting the air flowing into the planar space 15 as sound, the whistle member 21, stethoscope 31, microphone, A volume amplifier, a speaker and the like may be used in an appropriate combination.

Further, in each of the above-mentioned examples, the case where the water blocking sheet is laid at the waste disposal site has been described.
The present invention is also applied to the case where a waterproof sheet is laid on the bottom of a facility that stores water in a recess such as a water hazard of a golf course, a simple reservoir, a pond or a pool, or the surrounding structure of an underground structure is covered with a waterproof sheet. It can also be applied when laying a seat.

[0021]

As described in detail above, according to the method for detecting a defective portion of a joint portion of a water-blocking sheet and the apparatus for detecting a defective portion of the present invention, a planar space formed by an upper layer sheet and a lower layer sheet is formed. Vacuum suction is performed, and the air flowing into the planar space via the defective portion generated at the joint is detected as sound, so that the defective portion can be detected and specified quickly and easily on site with a simple configuration. It is also possible to accurately detect a minute defect portion.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a waste disposal site where a water-blocking sheet is laid using a method for detecting a defect in a joint portion of a water-impermeable sheet and a defect detection device according to the present invention.

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

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

FIG. 4 is an explanatory diagram showing a detection state of a water-blocking sheet according to the present invention.

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

[Explanation of symbols]

 10 Waste Disposal Site 11 Water Impermeable Sheet 12 Upper Water Impermeable Sheet 13 Lower Water Impermeable Sheet 15 Surface Space 16 Ventilation Mat 18,30 Defect Detection Device 19 Legs 20 Hollow Rod 21 Whistle Member 22 Closed Space 31 Stethoscope 32 Air Opening

Claims (3)

[Claims] 1. A method for detecting a defective portion of a joint portion of a waterproof sheet for detecting a defective portion at a joint portion of a double-layer waterproof sheet having an upper sheet and a lower sheet, the method comprising:
By vacuum sucking the planar space formed by the upper layer sheet and the lower layer sheet, and detecting the air flowing into the planar space through the defective portion generated in the joint portion as a sound, the defective portion is detected. A method for detecting a defect in a joint portion of a water-blocking sheet, which is characterized by detecting. 2. A detecting device used in the method for detecting a defect, wherein the tip is extended along the joint, and the tip is sandwiched between the joints and closely adhered to both sides thereof. From a leg portion that forms a box-shaped closed space together with the water-blocking sheet on the upper surface of the water sheet, and a hollow rod that is provided upright from the leg portion and that has a whistle member that generates sound by sucking air from the outside A defect detection device characterized by the following. 3. A detecting device used in the method for detecting a defect, wherein the tip is extended along the joint, and the tip is sandwiched between the joints and closely adhered to both sides of the joint. A defect portion characterized by comprising a leg portion that forms a box-shaped closed space together with the water-blocking sheet on the upper surface of the water sheet, and a hollow rod that stands upright from the leg portion and that has a stethoscope and an air opening. Detection device.