JPH09101228A - Breaking sheet detection method and breaking sheet capable of detecting breaking points - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a breaking point detection method excellent in workability, quality control, and durability, and a breaking sheet capable of detecting a breaking point. A method of detecting a breakage portion of a barrier sheet, comprising:
A large number of partition-specific conductive layers or conductive lines 4 are formed in the blocking sheet 1 to pass an electric current, and the break partition section of the blocking sheet is detected by the presence or absence of the current flow in the partition-specific conductive layers or conductive lines.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breaking point for detecting a breaking point of a shielding sheet for shielding on a shielding surface requiring water shielding or shielding such as a disposal site for waste or contaminated soil. The present invention relates to a detection method and a blocking sheet capable of detecting a breakage point.

[0002]

2. Description of the Related Art In recent years, leakage of water from a final disposal site for containing wastes, contaminated soil, etc. contains harmful substances, and pollution of groundwater and river water due to this has become a social problem. The cause is considered to be water leakage from the barrier sheet laid on the bottom of the final disposal site, which broke for some reason. Conventionally, as a method of detecting this breakage point, at the disposal site that requires a water barrier structure with a barrier sheet, the property that the barrier sheet is insulative is utilized, and the electric wires serving as electrodes are formed in a grid pattern above and below the sheet Once the sheet is placed and a hole is made in the sheet, the electrical characteristics of that part will change due to water leakage, so that the break point can be detected.

[0003]

However, in the conventional method of detecting a breakage point, it is necessary to dispose electric wires on the upper and lower sides of the sheet, which is troublesome and time-consuming. There is a problem in quality control that it is difficult to secure quality because there are many wires. Further, since the wiring is provided on the upper side of the sheet, there is a problem that the durability is doubtful due to damage from the landfill waste from above and corrosion due to leachate.

The present invention is to solve the above-mentioned conventional problems, and to provide a method of detecting a breaking point of a breaking sheet and a breaking sheet capable of detecting the breaking point, which are excellent in workability, quality control and durability. To aim.

[0005]

Therefore, the breaking point detecting method according to claim 1 of the present invention is a breaking point detecting method for a barrier sheet, wherein a large number of compartment-specific conductive layers or conductive lines are provided in the barrier sheet. Is formed and a current is passed therethrough, and the break section location of the blocking sheet is detected by the presence or absence of the current flow in the section-specific conductive layer or the conductive line.

Further, a breaking point detecting method according to a second aspect of the present invention is a breaking point detecting method for a breaking sheet, in which a conductive layer or a conductive line is formed in the breaking sheet to pass an electric current to cut off the breaking. Line electrodes are arranged in a grid pattern on the outside of the sheet, and the breakage point of the blocking sheet is detected by detecting the leakage current.

Further, the breaking point detecting method according to claim 3 of the present invention has a lead wire in the joining surface of the joining portion of the barrier sheet, and when the joining portion is broken, the lead wire is passed through the breaking point to the outside of the breaking sheet. It is characterized in that the breaking point is detected by detecting the strongest current flowing between the line electrodes arranged in a grid pattern.

According to a fourth aspect of the present invention, there is provided a breaking sheet capable of detecting a breakage point, and a conductive layer or a conductive line formed in an insulating sheet and the presence or absence of a current flowing through the conductive layer or the conductive line. And a means for detecting.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of the breaking sheet detecting method of the breaking sheet of the present invention and a breaking sheet capable of detecting breaking points, FIG. 1 (A) is a schematic diagram showing the entire structure of the breaking sheet, and FIG. 1 (A) is a diagram showing an example of the barrier sheet unit, and FIG. 1 (C) is a diagram showing an example of the barrier sheet unit showing a wiring example different from that in FIG. 1 (B).

In FIG. 1 (A), a blocking sheet 1 is a blocking sheet unit U1 provided with a large number of section-specific conductive lines.
~ U16. Each blocking sheet unit U1
As shown in FIG. 1 (B) or FIG. 1 (C), each of U1 to U16 forms a conductive line 4 made of a conductive material in a line shape with a single stroke in the insulating sheet 2 to form each blocking sheet unit U1. ~ U16 two conductors E1, E2, E3, E4, ...
Are connected in parallel to the power source, and the selector can detect whether or not a current is flowing through the conductive portion 4 of each of the blocking sheet units U1 to U16. Therefore, when the sheet 2 is broken and the line of the conductive portion 4 is cut, for example, no current flows between E1 and E2, and it is possible to detect in which of the blocking sheet units U1 to U16 the break has occurred. The one-stroke pattern is not limited to the example shown in the figure, and line intervals and patterns are designed in consideration of the sheet breaking direction.

In the present example, in order to detect the leakage point, the conductive layer or conductive line inside is cut along with the breakage of the sheet, and as a result, a current flows through the conductive layer or conductive line inside the one sheet unit. When it disappears, the presence or absence of breakage is detected. A number of such sheet units are joined together to cover the entire area. Therefore,
Compared with the conventional method, this method is a very simple method that can detect the breakage point of the sheet only by measuring whether or not an electric current flows, and it is possible to achieve a significant cost reduction in measuring equipment etc. it can. In addition, since there is a detection unit inside the blocking sheet, there is no risk of corrosion caused by the detection electrode being exposed to the leachate accumulated inside the disposal site as in the conventional case, and durability can be improved. .

It is also possible to provide a shielded room such as a safe room by adopting the barrier sheet as illustrated in FIG. 1 to form a wall, a floor, a ceiling or the like.

FIG. 2 is a view for explaining another example of the breaking sheet detecting method of the breaking sheet and the breaking sheet capable of detecting the breaking point according to the present invention, and FIG. 2 (B) and FIG. 2 (C) are cross-sectional views showing an example of the barrier sheet, and FIGS. 2 (D) and 2 (E) are diagrams for explaining a fracture point detection method.

In FIG. 2 (A), a blocking sheet 1 is laid on the bottom surface of a disposal site for containing wastes, contaminated soil and the like. The blocking sheet 1 has a three-layer structure in which a conductive layer 4 made of a conductive material is sandwiched between an insulating upper sheet 2 and a lower sheet 3, and a current flows through the conductive layer 4 and the blocking sheet 1 The leakage current detector 5 is arranged on the lower side.

As shown in FIG. 2 (B), the barrier sheet 1 has a three-layer structure in which a membranous fiber made of a conductive processed fiber is sandwiched between an insulating upper sheet 2 and a lower sheet 3 as a conductive layer 4. 2 or a conductive line 4 in which a conductive processed fiber is arranged in a mesh inside an insulating sheet 2 as shown in FIG. 2 (C).
The structure which formed is adopted.

The leakage current detector 5 is shown in FIGS.
As shown in (D), the line electrodes X1 to X5 and the line electrodes Y1 to
Y6 is arranged so as to be insulated in a grid shape in a right-angled direction such as the east-west direction and the north-south direction, and one line electrode in each direction is connected to the conductive layer or the conductive line 4. Each line electrode is connected to a junction box so that the current flowing through each line electrode can be measured.

As shown in FIG. 2 (A), when a breakage occurs in the blocking sheet 1, a circuit connecting the line electrode X3 and the conductive layer 4 and a circuit connecting Y4 and the conductive layer 4 closest to the breakage is formed. The strongest leakage current flows, and it is shown in Figure 2 (D) and Figure 2 (E).
As shown in, X3 and Y from the east-west and north-south directions, respectively.
By detecting 4, it is possible to identify the breakage point.

According to this embodiment, since the leakage current detecting portion is arranged outside the blocking sheet, it is possible to prevent corrosion of the electrodes due to the leachate inside the disposal site and improve the durability. In addition, since the leakage current flows directly through the holes in the cutoff sheet, it is easy to detect it with the leakage current detection unit directly below it, and it is possible to detect with higher accuracy than before. It is possible to increase the cost, reduce on-site work, and reduce costs.

FIG. 3 shows the structure of the joint portion of the barrier sheet according to the present invention, and FIG. 3 (A) is a sectional view of the joint portion.
3B is a plan view, and FIG. 3C is a cross-sectional view including a leakage current detection unit. The blocking sheets 1 are joined to each other at the two mechanical welding portions 6, and the lead wire 7 is arranged between the mechanical welding portions 6. Thus, when the welded portion 6 on the groundwater side is damaged, a current flows between the lead wire 7 and the leakage current detection unit 5, and the damage can be detected. FIG. 4 shows an example of arranging the barrier sheet in the present invention at the corner portion of the disposal site, in which the corner portion of the barrier sheet 1 located at the corner portion is obliquely cut and the end insulating treatment 9 is performed.

[0020]

As is apparent from the above description, according to the present invention, it is possible to provide a breaking point detecting method for a breaking sheet which is excellent in workability, quality control, and durability, and a breaking sheet capable of detecting a breaking point. it can. In addition to monitoring during landfill disposal, it can also be used for inspections at the time of completion, improving reliability.

[Brief description of the drawings]

1A and 1B show an example of a breaking sheet detecting method of a breaking sheet of the present invention and an example of a breaking sheet capable of detecting a breaking point, FIG. 1A is a schematic diagram showing the entire structure of the breaking sheet, and FIG. 1
The figure which shows the example of the interruption | blocking sheet unit of (A), FIG.1 (C)
[Fig. 2] is a diagram showing an example of wiring different from that in Fig. 1B and showing an example of a blocking sheet unit.

FIG. 2 is a diagram for explaining another example of the breaking sheet detection method for a breaking sheet and the breaking sheet capable of detecting breaking points according to the present invention, FIG. 2 (A) is a schematic configuration diagram, and FIG. ) And FIG. 2 (C) are cross-sectional views showing examples of the blocking sheet, FIG. 2 (D).
2 (E) is a diagram for explaining a fracture location detection method.

FIG. 3 shows a structure of a joint portion of the barrier sheet according to the present invention, FIG. 3 (A) is a sectional view of the joint portion, and FIG. 3 (B) is a plan view.
FIG. 3C is a cross-sectional view including a leakage current detector.

FIG. 4 is a plan view showing an example in which a barrier sheet according to the present invention is arranged at a corner portion of a disposal site.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Blocking sheet, 4 ... Conductive part, 5 ... Leakage current detection part X1-X5, Y1-Y6 ... Line electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junji Sasaki 1-2-3 Shibaura, Minato-ku, Tokyo Shimizu Corporation

Claims (4)

[Claims] 1. A method of detecting a breakage portion of a barrier sheet, comprising:
It is characterized in that a large number of partition-specific conductive layers or conductive lines are formed in the blocking sheet to pass an electric current, and a broken partition part of the blocking sheet is detected by the presence or absence of current flow in the partition-specific conductive layers or conductive lines. Method of detecting breakage of barrier sheet. 2. A method of detecting a breakage portion of a barrier sheet, the method comprising:
A conductive layer or a conductive line is formed in the blocking sheet to pass an electric current, line electrodes are arranged in a grid pattern on the outside of the blocking sheet, and a breakage point of the blocking sheet is detected by detecting a leakage current. A method for detecting breakage points in a barrier sheet. 3. The strongest flowing wire having a lead wire in the joint surface of the joint portion of the barrier sheet and flowing between the joint portion and the line electrodes arranged in a grid pattern outside the barrier sheet when the joint portion breaks. The breaking point detection method for a barrier sheet according to claim 2, wherein the breaking point is detected by detecting an electric current. 4. A breakage point detection device, comprising: a conductive layer or a conductive line formed in an insulating sheet; and a means for detecting the presence or absence of current flowing through the conductive layer or conductive line. Blocking sheet.