JP2000257047A - Waterproof sheet having water leakage detecting function and its laying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof sheet having water leakage detecting function and its laying method. SOLUTION: A waterproof sheet comprises a primary and secondary waterproof sheets. The primary waterproof sheet is formed water-tight with the secondary waterproof sheet to form them integrally with each other in one unit so that, if the primary waterproof sheet is broken, water can penetrate between two sheets. A plurality of units are used for the waterproof sheet. Then, a plurality of units are laid down so that water penetrates from the bottom part to the top part when the primary waterproof sheet is broken.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproofing sheet for civil engineering, and more particularly to a waterproofing sheet having a function of detecting water leakage and a method of laying the waterproofing sheet.

[0002]

2. Description of the Related Art In recent years, sheet waterproofing methods have been widely used in civil engineering works and the like. For example, sheets are laid on the bottom of dams and artificial ponds and used for water storage.On the other hand, in industrial waste treatment plants, so that sewage from wastes etc. does not flow into the soil. In addition, a sheet is laid in the processing plant. However, this waterproof sheet is damaged,
When a leak occurs, it is difficult to find the leak immediately, and it is not easy to identify the location of the leak.

[0003]

Particularly, in an industrial waste treatment plant, there is a high possibility that harmful substances are eluted, and it is not allowed to flow out into the soil. Moreover, this waste contains some sharp edges such as nails and waste materials.
As a result, a case in which the sheet is broken is scattered, and this measure is particularly required. Furthermore, when the laid sheet does not have sufficient followability to the ground, that is, when the ground has irregularities, a gap is generated between the sheet and the ground. It may enter or break, and in some cases does not serve the purpose of waterproofing.

[0004]

Means for Solving the Problems The first aspect of the present invention is to improve the above-mentioned drawbacks of the prior art and to devise it as a result of adopting a sheet having the following structure as a waterproof sheet. A second object of the present invention is to provide a method for laying the waterproof sheet. That is, a first aspect of the present invention is a waterproof sheet including a primary waterproof sheet and a secondary waterproof sheet, and when the primary waterproof sheet is broken, water permeates between the two sheets. The present invention provides a waterproof sheet having a water leakage detecting function, wherein a first waterproof sheet and a second waterproof sheet are integrated in a watertight manner to obtain a unit, and a plurality of the units are provided. .

Preferably, the present invention provides a waterproof sheet having a water leakage detecting function, characterized in that a thin water-permeable layer is sandwiched between the primary waterproof sheet and the secondary waterproof sheet. .

[0006] A second aspect of the present invention is a method for laying such a waterproof sheet, the method comprising:
A method of laying a waterproof sheet having a water leakage detection function, wherein the plurality of units are laid so that water permeates from the bottom toward the top end when the primary waterproof sheet breaks. Things.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to make the waterproof sheet of the present invention,
For example, a dent is formed on the ground surface, and a secondary waterproof sheet reaching the top end is laid on the bottom and side portions of the dent, and these are water-tightly integrated with each other to make the entire dent surface secondary waterproof. Cover with a sheet, then lay a long strip-shaped water-permeable thin layer on the surface of the secondary waterproof sheet to reach the top end, and further wrap the primary waterproof sheet wider than this water-permeable thin layer with this water-permeable thin layer. Lay it on a thin layer, and attach both width ends of this primary tarpaulin to the second
Next, it is only necessary to integrate the waterproof sheet with the waterproof sheet.
Along with the disposal pit, a secondary waterproof sheet reaching the top edge of the pit is laid on the bottom and side surfaces of the pit, and these are water-sealed or bonded together by heat welding or adhesive bonding to form the entire pit ground surface. Cover with a secondary waterproof sheet, then lay a long strip of water-permeable thin layer on the surface of the secondary waterproof sheet so that the tip reaches the surrounding groove, and further place the primary waterproof sheet on this water-permeable thin layer. By laying and laminating and integrating, or by laying a primary waterproof sheet wider than the water-permeable thin layer, both width ends of the primary waterproof sheet are integrated with the secondary waterproof sheet in a watertight manner. .

The three layers of the waterproof sheet are integrated in a water-tight manner in advance, rolled up in a roll shape, spread on the spot, and successively integrated in a water-tight manner by heat welding or the like. It is also possible to configure.

The primary waterproofing sheet and the secondary waterproofing sheet of the present invention include high-density, medium-density, and even low-density polyethylene (PE) and ethylene-vinyl acetate copolymer (EV).
A), polypropylene (PP) or graft-modified polyolefin-based elastomer (TPE) is used.

[0010] The water-permeable thin layer interposed in the sheet is
A nonwoven fabric, a net, and a communicating foam material are exemplified, and the first waterproof sheet and the second waterproof sheet described above are watertightly integrated in the width direction with the thin water-permeable layer interposed therebetween.

The waterproof sheet of the present invention is such that water can penetrate between the primary waterproof sheet and the secondary waterproof sheet as described above. That is, when this waterproof sheet is laid on the ground, for example, when the sheet is broken by a sharp object mixed in industrial waste, water leaks between the two sheets. Therefore, by examining the presence or absence of the water, breakage of the waterproof sheet or the like is detected. In particular, by laying this waterproof sheet on the ground and guiding its longitudinal end into the groove at the top end, it is possible to determine which part of the sheet was damaged when water flowed into the groove. It will be detected immediately.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The features of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a sectional view showing a part of the waterproof sheet of the present invention. In the figure, reference numeral 1 is a primary waterproof sheet,
Reference numeral 2 denotes a secondary waterproof sheet on the ground side. These are all made of EPDM-based TPE and have a thickness of 1.5
mm. In addition, a nonwoven fabric 3 made of synthetic fiber which becomes a thin water-permeable layer is interposed between the sheets 1 and 2. In this state, the widthwise ends of the sheets 1 and 2 are integrated by heat welding. I have.

In this waterproof sheet, for example, when the primary waterproof sheet 1 is broken and water leaks, water infiltrates into the three layers of the non-woven fabric, which penetrates in the longitudinal direction of the waterproof sheet,
The water leaks out to the end, and the presence or absence of water leakage can be detected only by monitoring the longitudinal end of the waterproof sheet.

FIG. 2 is a cross-sectional view showing an example in which a waterproof sheet is laid over a depression for storing industrial waste. In the figure, a groove 12 is formed at the top end surrounding the depression 11. And, to constitute the waterproof sheet of the present invention,
First, a secondary waterproof sheet 14 is laid on the ground 13, and the width end portion of the belt-shaped waterproof sheet 14 is welded to make the whole watertight. The secondary waterproof sheet 14 is laid so as to reach the inside of the groove 12 at the top end.

Next, as shown in FIG. 3, roll-shaped nonwoven fabrics 15 are laid side by side on the secondary waterproof sheet 14.
The nonwoven fabric 15 is also laid so as to reach the inside of the groove 12 at the top end.

Then, a roll-shaped primary waterproof sheet 16 slightly wider than this is placed on the non-woven fabric 15, and the primary waterproof sheet 14 is placed on both sides of the non-woven fabric 15 on both sides thereof. And the second waterproof sheet 16 are thermally welded. As described above, if the work on the primary waterproof sheet 16 is performed sequentially, the three-layer waterproof sheet is formed on the ground 13 as a whole.
When the primary waterproof sheet is torn, water permeates from the bottom toward the top.

FIG. 4 shows a second example of the second embodiment laid by the method described above.
Next waterproof sheet 14, non-woven fabric 15 and first waterproof sheet 1
It is sectional drawing of the unit part which shows the relationship of 6. That is, in this example, the secondary waterproof sheet 14 is first laid over a wide area on the ground 13, then the nonwoven fabric 15 is arranged at regular intervals, and the nonwoven fabric 15 is further covered with the primary waterproof sheet 16, To the second waterproof sheet 14 and heat welding 4,
5 and integrated. Therefore, a plurality of units each including the first waterproof sheet 16 and the second waterproof sheet 14 and the nonwoven fabric 15 are provided in the width direction, and water permeates in a direction perpendicular to the paper surface for each unit.

FIG. 5 is a cross-sectional view showing the periphery of the unit in another example of the waterproof sheet of the present invention. In this example, the nonwoven fabric 15 and the primary waterproof sheet 16 are superimposed on the secondary waterproof sheet 14 having a relatively large width, and the two sheets are integrated into a three-layer unit by heat welding or the like.
3, and the second waterproof sheet is overlapped with the ends in the width direction and thermally welded to form a waterproof sheet including a plurality of the units.

In the waterproof sheet of the present invention, for example,
When the primary waterproof sheet 16 of a certain unit is torn, water leaks into the nonwoven fabric 15 of the unit and gradually leaks out toward the groove 12 at the top end. As soon as the unit is reached, the unit that caused the leak will be known.

[0020]

The present invention relates to a waterproof sheet having a function of detecting water leakage as described above and a method of laying the waterproof sheet. Even if the primary waterproof sheet may be broken by a sharp tip, The damaged part was immediately identified, so that the entry of harmful substances into the soil and the like could be immediately prevented.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a waterproof sheet of the present invention.

FIG. 2 is a cross-sectional view showing a state where a waterproof sheet of the present invention is laid.

FIG. 3 is a perspective view showing one stage of a method of laying a waterproof sheet in FIG. 2;

FIG. 4 is a sectional view showing a unit portion of the waterproof sheet of the present invention.

FIG. 5 is a cross-sectional view showing the periphery of a unit in another example of the waterproof sheet of the present invention.

[Explanation of symbols]

 1 Primary Waterproof Sheet 2 Secondary Waterproof Sheet 3 Nonwoven Fabric 4 Heat Welding Part 5 Heat Welding Part 11 Depression 12 Groove 13 Ground 14 Secondary Waterproof sheet 15 Non-woven fabric 16 ‥‥ Primary waterproof sheet

Claims (3)

[Claims] 1. A waterproof sheet comprising a primary waterproof sheet and a secondary waterproof sheet, wherein the first waterproof sheet is broken so that water can permeate between the two sheets when the primary waterproof sheet is broken. A waterproof sheet having a water leak detecting function, wherein a primary waterproof sheet and a secondary waterproof sheet are integrated in a watertight manner into a unit, and a plurality of the units are provided. 2. The waterproof sheet having a water leakage detecting function according to claim 1, wherein a thin water-permeable layer is sandwiched between the first waterproof sheet and the second waterproof sheet. 3. The method of laying a waterproof sheet according to claim 1, wherein the first waterproof sheet is torn from a bottom to a top when a primary waterproof sheet is broken. A method of laying a waterproof sheet having a water leakage detection function, wherein the plurality of units are laid so that water permeates toward the waterproof sheet.