JP2003136033A - Impervious sheet and impervious structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impervious sheet having a structure that a stress generated by a traveling of a heavy machinery, etc., is relaxed and preventing a damage of the sheet caused by a concentration of the stress and a water- shielding structure using the water-shielding sheet. SOLUTION: The impervious sheet 6 is used for the impervious structure established along a recessed part of a ground 1. An impervious sheet provided with an expandable/shrinkable expansion/shrinkage part provided at a predetermined interval is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-blocking sheet and a water-blocking structure laid in a waste disposal site, and more particularly, to a stress-relaxation structure for preventing a sheet from breaking due to stress concentration. The present invention relates to an impermeable sheet provided and an impermeable structure using the impermeable sheet.

[0002]

2. Description of the Related Art A facility that produces leachate that does not meet drainage standards that may pollute groundwater or rivers has a disposal site for treating leachate. Impermeable works such as impermeable sheets are installed. Generally, the landfill site is used after laying a water barrier sheet and installing protective soil.

However, recently, there are many reports that the above-mentioned water-blocking sheet does not perform a sufficient function and water leakage occurs at the existing disposal site. The causes of water leakage in this case are poor construction of joints such as joints and joints with surrounding structures in water-blocking sheets, damage by projections, action of excessive stress due to running of heavy machinery on the above-mentioned protective soil, heavy machinery. The stress concentration due to the wave action transmitted through the protective soil due to the running of the road and the fatigue fracture due to the repeated load are mentioned. The above-mentioned protective soil is used to directly protect the water-blocking sheet against running of heavy machinery, etc.
Since the depth is about 0 cm, it cannot be said that it is sufficient protection against running of heavy machinery, etc., and when stress occurs in the water shield sheet due to the above wave operation, stress concentrates on weak parts such as seams of the water shield sheet. Therefore, there has been a problem that the water blocking sheet is easily damaged.

[0004]

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned problems, the present invention has a structure that alleviates the stress generated by the running of heavy machinery and the like, and a water-blocking sheet that prevents the damage of the sheet due to the concentration of the stress. An object is to provide a water blocking structure using the water blocking sheet.

[0005]

[Means for Solving the Problems] That is,
This can be solved by adopting the water blocking sheet and the water blocking structure of the present invention.

According to the first aspect of the present invention, there is provided a water shield sheet for use in a water shield structure constructed along a recess in the ground, the shield sheet having easily expandable and contractible portions provided at predetermined intervals. A water sheet is provided.

According to the second aspect of the present invention, there is provided a water-impermeable sheet in which the stretchable portion is a bellows-shaped sheet.

According to the invention of claim 3 of the present invention, there is provided a water-blocking sheet, wherein the elastic portion is made of a rubber material.

According to a fourth aspect of the present invention, there is provided a water-impermeable sheet, wherein the water-impermeable sheet has a structure in which the stretchable portion is folded back.

According to the fifth aspect of the present invention, there is provided a water-impervious structure constructed along the recess of the ground, which is laid on the ground of the recess and provided at a predetermined interval. Provided is a water-impervious structure including a water-impermeable sheet having a flexible portion.

According to a sixth aspect of the present invention, there is provided a water-impervious structure in which the elastic portion is a bellows-shaped sheet.

According to a seventh aspect of the present invention, there is provided a water-impervious structure in which the elastic portion is made of a rubber material.

According to an eighth aspect of the present invention, there is provided a water-impervious structure, wherein the water-impermeable sheet has a structure in which the stretchable portion is folded back.

According to a ninth aspect of the present invention, there is provided the water-impervious structure which includes a friction reducing material laid on the water-impermeable sheet.

According to a tenth aspect of the present invention, there is provided the water-impervious structure which further includes an elastic member laid on the friction-reducing material.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The water-blocking sheet of the present invention will be described in detail below with reference to embodiments, but the present invention is not limited to the following embodiments. FIG. 1 is a diagram showing a schematic cross section of a waste disposal site to which the water blocking sheet of the present invention is applied. The waste disposal site to which the present invention is applied is composed of a recess in the ground 1 and a water-impervious structure 2 provided on the ground 1 along the recess. The recess of the ground 1 may be artificially formed by digging from the surface of the ground toward the foundation ground, and when a swamp or valley such as a mountain portion is used, its topography can be used. In such a recess, the water-blocking structure 2 is provided, and the waste 3 is dumped so that the sewage generated by rainwater or the like does not leach out of the water-blocking structure 2. When the waste 3 is dumped, the heavy equipment 4 such as a waste transport vehicle travels on the water blocking structure 2.

The water-impervious structure 2 shown in FIG. 1 comprises a protective sand or soil 5 adjacent to the waste 3, a water-impervious sheet 6 adjacent to the protective sand or soil 5, and the lower side of the water-impervious sheet 6. It is composed of the protective sand or the protective soil 7 provided on the. The protective sand or protective soil 5 shown in FIG. 1 is provided in order to protect the impermeable sheet 6 from being damaged by the traveling of the heavy equipment 4 or the dumping of the waste 3 described above. It is installed up to a height of about 100 cm.

The water-blocking sheet 6 shown in FIG. 1 is a synthetic rubber or plastic sheet, specifically a linear low-density polyethylene (LLD) produced by a metallocene catalyst.
PE), medium density polyethylene (MDPE), or linear low density polyethylene (LLDPE) manufactured with Ziegler-Natta catalyst, medium density polyethylene (MDPE)
Water-impervious sheets formed of olefin resins and the like. Also, its thickness and material,
Any material can be used as long as it can obtain the required water impermeability and durability.

Further, the water-blocking sheet 6 shown in FIG. 1 has a stress-relaxing structure so that the stress caused by the wave action generated by the heavy equipment 4 traveling on the protective sand or the protective soil 5 can be relieved. Has become. Here, “for wave operation” means that the rotational force is transmitted to the protective sand or the protective soil 5 by the rotation of the wheels of the heavy equipment 4, and the rotational force is transmitted as a wave to the impermeable sheet 6. In the water-blocking sheet not provided with the stress relaxation structure, the rotational force applied to the protective sand or the protective soil 5 is transmitted to the water-blocking sheet 6 at a predetermined position by the wave action, and the transmitted rotational force causes the wheel to move. The water-impervious sheet 6 located at the lower part is rolled up, and due to the rolling force, stress concentrates on weakly stressed portions such as the above-mentioned joints, resulting in sheet breakage. However, since the water-impervious sheet 6 of the present invention has a stress relaxation structure, even if the stress due to the wave operation is transmitted to the water-impermeable sheet 6, the expansion / contraction portion of the water-impermeable sheet 6 relieves the stress. The structure is designed so that damage to the seat does not occur.

The protective sand or protective soil 7 shown in FIG. 1 can have a low water-permeable structure in addition to the protection of the water-impervious sheet 6 to be laid. The water-impervious layer or the water-impervious layer made of asphalt is used, and specifically, a material having low water permeability such as clay, asphalt, or concrete is used, and it is also possible to use these in appropriate combination. The protective sand or the protective soil 7 may be provided as needed, and may not be provided as long as the water blocking sheet 6 can be sufficiently protected in the recess of the ground 1.

In the present invention, the water-impervious structure 2 may use double water-impervious sheets 6, or between the impermeable sheet 6 and the protective sand or protective soil 5, 7 installed above and below it. It may have a structure provided with a water permeable layer such as a non-woven fabric. Also,
The protective sand or protective soil 5, 7 can be as high as required. Hereinafter, examples of the water blocking sheet 6 that can be used in the water blocking structure 2 shown in FIG. 1 will be shown.

FIG. 2 is a view showing a first embodiment of the water-blocking sheet of the present invention. The water-permeable sheet 6 shown in FIG. 2 has a structure in which the stretchable portions are joined to each other at predetermined intervals and the bellows-shaped sheets 6a and 6b are joined together, so that the stretchable portion is easier to stretch than the portions other than the stretchable portion. In FIG. 2, the protective sand or the protective soil 7 is installed in the recess of the ground 1, and the protective sand or the protective soil 7 is installed.
The water-blocking sheet 6 is laid on the top, and the protection sand or the protection soil 5 is installed on the top. Further, the heavy equipment 4 runs on the protective sand or the protective soil 5, and the waste is dumped at a predetermined position. In the embodiment shown in FIG. 2, the rotating force of the wheels of the heavy equipment 4 is transmitted through the protective sand or the protective soil 5 as the wave A, and the water impervious sheet 6 is stressed. In the water impermeable sheet 6, for example, when wave action is applied between the bellows-shaped sheets 6a and 6b, the sheet 6a contracts and the sheet 6b extends, or the sheet 6a extends and the sheet 6b contracts. The stress transmitted to the periphery of the sheets 6a and 6b is reduced. As a result, stress that would damage the joints of the sheets is not applied, and the sheets can be prevented from being damaged.

In the present invention, any spacing, number, or
Bellows-shaped sheets 6a and 6b having a width and a size may be provided. The bellows-shaped sheets 6a and 6b can be produced by adhering or welding to a commonly used flat sheet. Further, when the bellows shape is formed at a predetermined position of the water-impervious sheet 6, it can be manufactured by joining molds having a bellows shape and capable of expanding and contracting. In the present invention, any material other than those described above can be used as long as it can form a bellows shape on the water-blocking sheet 6 at predetermined intervals. Further, in the present invention, the bellows shape may be any of a mountain shape, a wave shape, and the like. Further, in the present invention, the water-impervious sheet 6 can be provided with a bellows shape so that it can be expanded and contracted in any direction.

FIG. 3 is a view showing a second embodiment of the water blocking sheet of the present invention. The water-blocking sheet 6 shown in FIG.
The stretchable portion of the water-blocking sheet 6 shown in FIG. 6 has a folded structure. Similar to FIG. 2, also in FIG. 3, protective sand or protective soil 7 is installed in the recess of the ground 1 shown in FIG. 1, a water-blocking sheet 6 is laid on the protective sand or protective soil 7, and further protected. Sand or protective soil 5 is installed. Further, the heavy equipment 4 runs on the protective sand or the protective soil 5, and the waste is dumped at a predetermined position. The water-blocking sheet 6 shown in FIG. 3 is provided with bellows-shaped sheets 6a and 6b at predetermined intervals as shown in FIG.
The bellows-shaped sheets 6a and 6b are folded back, and the bellows-shaped sheets 6a and 6b are respectively the upper and lower flat sheets 6.
It has a structure sandwiched between p. By doing so, the stress can be more relaxed as compared with the water shield sheet 6 shown in FIG.

The heavy equipment 4 shown in FIG.
When traveling above, the protective sand or the protective soil 5 is transmitted as the wave A, and the stress is transmitted to the water-impervious sheet 6. In the embodiment shown in FIG. 3, the stress transmitted to the water-impervious sheet 6 is not seen in the bellows-shaped sheets 6a and 6b, but the folded portion 6c.
Is relaxed and the stress transmitted to the surroundings is reduced. Figure 2
The same stress as that applied to the water-blocking sheet 6 shown in FIG.
When it is added to the water-impervious sheet 6 shown in (4), it expands and contracts in the direction opposite to the expansion and contraction direction of the bellows-shaped sheets 6a, 6b.
That is, by applying stress, the water-blocking sheet 6
2 extends, the bellows-shaped sheet 6a or 6b expands in the water-impervious sheet 6 shown in FIG. 2, and the bellows-shaped sheet 6a or 6b contracts in the water-impermeable sheet 6 shown in FIG. The water impervious sheet 6 shown in FIG. 3 relieves stress as the bellows-shaped sheets 6a and 6b expand and contract, and the fold-back portion 6c extends to a state without fold-back as shown in FIG. , Bellows-shaped sheet 6
When a and the sheet 6b are close to each other, the sheet can be contracted. As described above, the water shield sheet 6 shown in FIG. 3 has a structure capable of relieving stress more than the water shield sheet 6 shown in FIG.

FIG. 4 is a view showing a third embodiment of the water blocking sheet of the present invention. The water-blocking sheet 6 shown in FIG.
Similar to the water-impervious sheet 6 shown in FIG. 3, the folded-back portion 6c is provided, but the bellows-shaped sheets 6a and 6b in FIG.
The stretchable portions are the sheets 6d and 6e that are easily stretchable. The easily stretchable sheets 6d and 6e shown in FIG. 4 are made of a material that is easier to stretch than the flat sheet 6p other than the stretchable portion, and in the present invention, are rubber materials having a water blocking function and a high elastic force. be able to. In the present invention, the rubber material may be, for example, a rubber sheet using natural rubber or butadiene rubber. As a result, even if a stress is generated by the wave operation, it can be relaxed by the easily stretchable sheets 6d and 6e.
The stress transmitted to the periphery of e can be reduced. Figure 4
In the embodiment shown in FIG.
When traveling over, the wave motion due to the rotation of the wheels of the heavy equipment 4 is transmitted through the protective sand or the protective soil 5, and the water impervious sheet 6 is stressed. The stress generated in the water-impervious sheet 6 is relaxed by the folded-back portion 6c and the easily stretchable sheets 6d and 6e, and the stress transmitted to the surroundings is reduced.

FIG. 5 is a view showing another embodiment of the water-blocking structure of the present invention. As in the case of FIG. 2, the water-impervious structure shown in FIG. 5 has protective sand or soil 7 installed on the recess of the ground 1, and the water-impervious sheet 6 laid on the protective sand or soil 7, The friction reducing material 8 is laid on the inner surface of which the protective sand or the protective soil 5 is further installed. In FIG. 5, after the protection sand or the protection soil 5 is installed, the heavy equipment 4 runs and the waste is dumped. In the water-impervious structure shown in FIG. 5, when the heavy machine 4 travels, the wave A is transmitted through the protective sand or the protective soil 5, and the friction reducing material 8 reduces the stress caused by the wave A. Regarding the stress transmitted through the protective sand or the protective soil 5, the stress transmitted to the friction reducing material 8 is reduced because the friction resistance of the surface of the friction reducing material 8 is small. Thereby, the friction reducing material 8 to the water-blocking sheet 6
Since the stress transmitted to the sheet is also reduced, it is possible to prevent breakage of a stress-sensitive portion such as a joint portion of the sheet. In FIG. 5, the water-blocking sheet 6 is provided with the above-mentioned bellows-shaped sheet as a stretchable portion, and the friction reducing material 8
It is possible to further reduce the stress transmitted from. In the present invention, when the friction reducing material 8 is provided, it is possible to use a flat sheet having no stretchable portion in the water-blocking sheet 6.

As the friction reducing material 8 shown in FIG. 5, a friction reducing sheet can be used, and as the friction reducing sheet, one having a smooth surface can be used. For example,
Examples thereof include high molecular weight polyethylene films and sheets coated with grease. In the present invention, the friction reducing sheet may be laid adjacent to the water impervious sheet 6, or the water impervious sheet 6 may be joined to the friction reducing sheet.

FIG. 6 is a view showing still another embodiment of the water blocking structure of the present invention. The water-impervious structure shown in FIG. 6 has a structure in which elastic material 9 is further laid on the friction reducing material 8 shown in FIG. 5, and protective sand or protective soil 5 is installed on the elastic material 9. . In FIG. 6, after the protection sand or the protection soil 5 is installed, the heavy equipment 4 runs and the waste is dumped. In the water-impervious structure shown in FIG. 6, stress is reduced by the wave motion caused by traveling of the heavy equipment 4 being transmitted through the protective sand or the protective soil 5 and the elastic material 9 expanding and contracting.
Furthermore, the stress transmitted from the stretchable material 9 to the friction reducing material 8 becomes even smaller because the friction resistance of the surface of the friction reducing material 8 is small. As a result, the stress transmitted from the friction reducing material 8 to the water-impervious sheet 6 is further reduced, and damage to stress-sensitive portions such as the joints of the sheets can be prevented. In FIG. 6, the waterproof sheet 6
The above-mentioned bellows-shaped sheet is provided as a stretchable portion, and the stress transmitted from the friction reducing material 8 can be further relieved. In the present invention,
When the friction reducing material 8 and the elastic material 9 are provided, a flat sheet having no elastic portion can be used as the water-blocking sheet 6.

As the elastic material 9 shown in FIG. 6, an elastic sheet such as the rubber sheet described above can be used. In the present invention, the stretchable sheet may be laid adjacent to the water blocking sheet 6 together with the friction reducing sheet, or may be laid adjacent to the water blocking sheet 6 joined with the friction reducing sheet.

[0031]

As described above, the water blocking sheet and the water blocking structure of the present invention alleviate the stress caused by the wave operation from the heavy machine traveling on the protective sand or the protective soil installed on the water blocking sheet, It is possible to prevent breakage of a weakly stressed portion such as a sheet joint. Further, the waterproof sheet and the waterproof structure of the present invention have a simple structure and can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic cross section of a waste disposal site to which a water-blocking sheet of the present invention is applied.

FIG. 2 is a view showing a first embodiment of the water-blocking sheet of the present invention.

FIG. 3 is a view showing a second embodiment of the water-blocking sheet of the present invention.

FIG. 4 is a view showing a third embodiment of the water-blocking sheet of the present invention.

FIG. 5 is a view showing another embodiment of the water-impervious structure of the present invention.

FIG. 6 is a view showing still another embodiment of the water-impervious structure of the present invention.

[Explanation of symbols]

1 ... Ground 2 ... Water-blocking structure 3 ... Waste 4 ... heavy machinery 5, 7 ... Protective sand or soil 6 ... Water-blocking sheet 6a, 6b ... Bellows-shaped sheet 6c ... folding part 6d, 6e ... Sheets that can easily expand and contract 6p ... flat sheet 8 ... Friction reducing material 9 ... Elastic material A ... Hado

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Keiichi Miyazaki             Nishimatsuken 1-20-10 Toranomon, Minato-ku, Tokyo             Inside the corporation (72) Inventor Tsutomu Tanaka             Nishimatsuken 1-20-10 Toranomon, Minato-ku, Tokyo             Inside the corporation (72) Inventor Yukio Sakai             9-11 Kitankita 1-chome, Chiyoda-ku, Tokyo             Foundation Ground Consultants Co., Ltd. (72) Inventor Shigeru Miki             9-11 Kitankita 1-chome, Chiyoda-ku, Tokyo             Foundation Ground Consultants Co., Ltd. F-term (reference) 4D004 AA46 AB01 BB04 BB05

Claims (10)

[Claims] 1. A water-blocking sheet used for a water-blocking structure constructed along a recess in the ground, comprising a stretchable portion that is provided at predetermined intervals and is easily stretchable. 2. The waterproof sheet according to claim 1, wherein the stretchable portion is a bellows-shaped sheet. 3. The stretchable portion is made of a rubber material.
Or the water-blocking sheet according to 2. 4. The waterproof sheet according to claim 1, wherein the stretchable portion of the waterproof sheet has a folded structure. 5. A water-blocking structure constructed along a recess in the ground, comprising a water-blocking sheet laid on the ground in the recess and provided with easily expandable stretchable portions provided at predetermined intervals. , Water impermeable structure. 6. The water-blocking structure according to claim 5, wherein the stretchable portion is a bellows-shaped sheet. 7. The stretchable portion is made of a rubber material.
Or the water-impervious structure according to item 6. 8. The water shield structure according to claim 5, wherein the water shield sheet has a structure in which the stretchable portion is folded back. 9. The water impermeable structure according to claim 5, further comprising a friction reducing material laid on the water impermeable sheet.
Impermeable structure described in paragraph. 10. The water-impervious structure according to claim 9, wherein the water-impervious structure further includes a stretchable material laid on the friction reducing material.