JPH08229529A - Impervious sheet structure and its installation method - Google Patents

Abstract

PURPOSE: To prevent sheet rupture by adopting a margin for allowance to release the tension of an impervious sheet in an impervious sheet structure and relieving the tension acted on the sheet when the impervious sheet is pulled and elongated by a waste weight. CONSTITUTION: An air bag 7 into and out of which gas is freely put is interposed between the subsurface 2 of the shoulder 4 of slope of the impervious sheet 3b and the sheet 3b of the impervious sheet structure laid with the impervious sheet on the application surface of a waste treatment plant, water storage basin, water channel, etc. The ends of sheets are embedded and fixed into the subsurface 2 by means of blocks 8.

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 structure laid in a waste treatment plant or the like, and more particularly to the above-mentioned water-blocking sheet for relaxing the tension of the water-blocking sheet to prevent the sheet from breaking. The present invention relates to a sheet structure and its construction method.

[0002]

2. Description of the Related Art Conventionally, in a waste treatment plant, a reservoir, a waterway, etc., in order to prevent leakage of pollutants and water from waste, a water-blocking sheet is laid along the construction surface. ing.

For example, in a waste treatment plant, FIGS.
As shown in (1), there are many waste treatment plants 1 for constructing dams in the Tanizawa area or digging pond-shaped holes in the ground and dumping industrial wastes into the holes. At present, the sewage from the waste has penetrated into the ground of the treatment plant to pollute the groundwater, flow into the river, die trees around it, and other problems that adversely affect the surrounding environment are being noticed. In order to prevent the water from penetrating into the ground, water impervious sheets 3a and 3b made of synthetic resin or rubber such as vinyl chloride and high density polyeletin are laid on the ground surface of the treatment plant.

However, such water-blocking sheets 3a, 3
By laying b, sewage can be prevented from leaking, but the impermeable sheet is made of an elastomer such as synthetic resin or rubber, and when abnormal force is applied to the impermeable sheet, the joint part may peel off. May be damaged.

The following are possible causes of the above problems. One is that the impermeable sheet made of elastomer expands and contracts due to changes in temperature due to seasonal changes, but due to the contraction of the impermeable sheet itself, tension is applied to the impermeable sheet, which reduces the strength of the impermeable sheet.
This means that the joints will peel off, and the other is that the waste is gradually dumped into the treatment plant, which usually takes months to fill the treatment plant. It is possible that the weight of the waste may stretch the impermeable sheet as it accumulates and eventually damage it.

To further explain this in detail, in FIG. 2, the water-impermeable sheet is laid on the entire bottom surface and slope of the treatment plant, and the bottom sheet 3a and the slope sheet 3b are joined together to form a water-impermeable sheet. It is completely blocked so that sewage does not leak to the ground side. At this time, the bottom sheet 3a does not need to be fixed because the base is horizontal, but the slope sheet 3b is laid on the inclined surface, so the top of the slope, that is, the shoulder portion 4
In, the impermeable sheet must be fixed to the groundwork.
When the waste is dumped in such a state, the weight of the waste stretches the water-blocking sheet on the slope, and the water-blocking sheet on the upper side of the slope in particular is subjected to a considerable amount of tension. Can extend to

Therefore, in order to relieve the tension related to the waterproof sheet, a small step portion 5 is provided in the middle of the slope as shown in FIG. At 6 (bottom of the slope), a method of slackening the water-blocking sheet to allow a margin is adopted, but the former is not a sufficient measure at present, and the latter is also dumped with waste. There is a problem that the loosened seat cannot be extended after the bottom of the slope has been filled up, so at present it is not a sufficient countermeasure.

By the way, the above-mentioned method has been used recently.
Furthermore, there is a technique in which the water-impervious sheet is lifted with a cushioning material made of synthetic resin interposed in the shoulder portion (outer peripheral edge portion), and the cushioning material is crushed by the tension applied to the water-impervious sheet to relieve the tension. Proposed. (Japanese Unexamined Patent Publication No.
(See Japanese Patent No. 247409)

Further, by providing an undulating portion for allowing the extension of the sheet, the subsidence of the ground, the extension and contraction due to the change of the environmental temperature, and the dragging due to the increase of the input amount of waste, etc. To prevent the damage caused by them (see Japanese Patent Laid-Open No. 3-33312) or to form the sheet joint with a locking portion for locking the embankment (Japanese Patent Laid-Open No. 64-75086). (See the gazette) and other proposals have also been made.

[0010]

However, the above-mentioned Japanese Unexamined Patent Application Publication No.
According to the technique described in Japanese Patent No. 247409, when the water blocking sheet is laid at the shoulder, the water blocking sheet is laid on the surface projected by the cushioning material. The slope sheet is usually placed on the shoulder of the water shield sheet, which is a roll, and the roll is laid while unraveling the roll toward the bottom of the roll, but if the cushioning material is not fixed to the ground, the position may shift. , The adjoining sheet had to be joined on the cushioning material, which made the work troublesome. Moreover, when tension is applied to the impermeable sheet, even if the cushioning material is crushed and the tension is loosened, the force to restore the original shape of the cushioning material acts on the impermeable sheet. However, there is still a problem that the tension applied by the weight of the waste cannot be completely reduced to zero, and the same can be said for each of the other proposed methods.

The present invention copes with the actual situation as described above, and in particular, in a water-impermeable sheet structure, an air bag in which an internal gas can freely flow in and out is interposed between the water-impermeable sheet and the base in the shoulder of the shoulder. The purpose is to take a margin to loosen the tension of the impermeable sheet, reduce the large tension applied to the impermeable sheet due to the weight of such waste, and prevent the sheet from breaking. It is a thing.

[0012]

[Means for Solving the Problems] That is, the first feature of the present invention which meets the above-mentioned object is to lay a water-blocking sheet on the construction surface of a waste treatment plant, a reservoir, a waterway or the like as described in claim 1. In the above water-impermeable sheet structure, an air bag in which gas can be freely taken in and out is interposed between the water impermeable sheet and the base of the shoulder portion of the water impermeable sheet.

The invention according to claims 4 and 5 is a method for constructing the above structure, and in constructing an impermeable sheet on the slopes and bottom surfaces of the waste treatment plant, reservoir, waterway, etc. having slopes and bottom surfaces. , A tube or hose-like air bag is placed in the upper shoulder of the slope, and a water barrier sheet of a predetermined width is laid on the air bag so as to cover the air bag. While joining together, the end of the impermeable sheet on the slope is embedded and fixed in the ground with soil or concrete blocks, and at the time of placement, it is placed in a state in which the air bag has been degassed, fixed by embedding, and then injected with gas. Each is characterized by doing.

Here, the air bag is provided with a hose and a valve for taking in and out gas.
Numerals 6 and 6 are further equipped with an air pressure gauge and an air pump on the bulges to facilitate the maintenance and control of pressure.

Further, the inventions according to claims 3 and 7 are such that the air bag in each of the above inventions has a structure in which the air chambers are independent at predetermined intervals.

[0016]

When the waste water is dumped and the weight of the water blocking sheet is heavy in the water blocking sheet structure constructed as above, the water blocking sheet laid on the slope as the first step is located below the slope. When the air bag is pulled toward, the air bag is pressed down from above by the water-impervious sheet and spreads to the left and right voids, and the gas inside is compressed to reduce the volume. It will come out. For example, expansion and contraction of the impermeable sheet due to changes in temperature due to seasonal changes may cause some increase or decrease in tension, but if this is the case, the effect of this first stage should be enough to alleviate the tension. You can

That is, since the air bag is always compressed up to this point, the tension corresponding to the sum of the "tension due to the weight of the water blocking sheet" and the "tension generated when the air bag pushes the water blocking sheet back" is applied. It takes.

Then, as a second step, by discharging the gas in the air bag to the outside, the volume of the air bag is greatly reduced, and the water shielding sheet is fed out to the lower side of the slope by that amount. Can relieve a large tension. That is, in this case, the tension applied to the impermeable sheet can be relaxed to almost the same level as the “tension due to the weight of the impermeable sheet” when there is no waste.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 show an example of the water-blocking sheet structure according to the present invention in which an air bag is installed. In these figures, 1 shows a flat rectangular mortar-shaped waste treatment plant. The size is around 300m x 100m, and the depth is usually 15
It is about 30 m.

Further, as shown in the figure, a plurality of rows of water blocking sheets 3a having a constant width are spread over the bottom surface of the waste treatment plant 1, and the water blocking sheets 3a are adjacent to each other.
Combined with each other, a tube or hose-shaped air bag 7 that circulates around the treatment plant 1 is provided at the upper shoulder 4 on the upper slope.
Is arranged, and a water-blocking sheet 3b having a constant width is installed on the air bag 7 so as to cover the air bag 7.

Here, the water-blocking sheets 3b are arranged on the slope, and the water-blocking sheets 3b placed adjacent to each other are joined to each other. Further, as shown in detail in FIG. 3, the sloped water-impervious sheet 3b is laid so as to cover the airbag 7 at the shoulder portion 4, and the end portion is fixed by embedding it in the base 2 with the block 8.

The water blocking sheets 3a and 3b are vulcanized rubbers such as EPDM, butyl rubber, chloroprene rubber, nitrile rubber, styrene butadiene rubber, chlorosulfonated polyethylene, polyvinyl chloride, chlorinated polyethylene, ethylene vinyl acetate, polyethylene, polyurethane. It is made of resin such as, and its thickness is usually 0.8 to 3.0.
The width is about 1 mm and the width is set to 1 to 10 m from the stool to be transported by rolling the sheet. Of these, the water-impervious sheet 3a laid on the bottom surface is laid on a horizontal surface, so that tension is not applied so much. Therefore, a sheet made of only an elastomer such as rubber or resin may be used, but the water-impervious sheet 3b laid on the slope is not required. In this case, since tension is applied at least by its own weight, it is preferable to embed the reinforcing base material in the elastomer so that it is difficult to stretch.

As the base material to be embedded, a film or knitted cloth made of an organic synthetic resin such as polyethylene, polyester, polyvinyl chloride, polypropylene, polyamide, aromatic polyamide, polyvinyl alcohol or polyurethane,
Woven cloth, non-woven cloth, and other woven cloth made of inorganic fibers such as glass fibers or metal fibers can be used. In addition, it is preferable that the water-blocking sheets 3a and 3b have a white color so as not to be easily affected by seasonal and day / night temperature changes.

In the case of water-impermeable sheets made of vulcanized rubber, the water-impermeable sheets 3a and 3b are joined together by a method in which a tape of unvulcanized rubber is interposed between the overlapping sheets of adjacent sheets, and heat-pressing is used for cross-linking joining. Or a method of joining with a rubber-based or olefin-based adhesive, heat fusion with a thermoplastic resin interposed,
It is also possible to weld using a solvent.

Next, the air bag 7 which is a feature of the present invention
Is a rubber hose made of chloroprene rubber, butyl rubber, etc., such as a long tire tube, or a resin such as polyethylene or polypropylene, or a woven cloth hose that has been subjected to a non-breathing treatment with resin or rubber. Things etc. are used. The shape is not limited to a continuous hose-shaped air chamber, but the air chambers are independent at predetermined intervals as shown in FIG. 4, or hose-shaped objects of a predetermined length are arranged side by side as shown in FIG. May be. When the air chambers are made independent, even if a hole is opened (punctured) in one air chamber, the other air chambers can obtain a predetermined effect, so that there is a merit of higher safety.

Besides, as shown in FIG. 6, it is possible to use two hose-shaped air bags 7 arranged side by side and various forms. It is to be noted that each air chamber is attached with a hose 9 and a valve 10 for injecting gas into the air chamber and discharging the gas inside.

Since the size of the air bag 7 is empirically set to about 2 to 5% of the sheet length, it is preferably about 5 to 15 cm. Further, when the form of the treatment plant 1 has a small step portion 5 in the middle of the slope, an air bag 7 is provided not only on the slope shoulder portion 4 but also on the small step portion 5 to reduce the tension of the sheet below the small step portion 5. can do.

As described above, the air bag 7 is arranged between the water impervious sheet 3b and the base 2 so as to support the water impervious sheet 3b at the top. Due to the presence of the voids 11 as described above, the air bag is deformed so as to escape into the left and right voids 11 as shown in FIG. The tension of can be weakened.

Next, in the impermeable sheet structure constructed as described above, the mode in which waste is dumped and the impermeable sheet is weighted, as described in the above-mentioned operation, is shown in FIG. 7 as the first step. As shown in the figure, when the water-blocking sheet b laid on the slope is pulled downward on the slope, the air bag 7 is pressed down from above by the water-blocking sheet 3b and spreads to the left and right voids 11 and the internal gas Is compressed and the volume is reduced, and the water-blocking sheet 3b is pushed out to the lower side of the slope by that amount.

Then, as a second step, as shown in FIG. 8, the gas in the air bag 7 is discharged to the outside, so that the volume of the air bag 7 is greatly reduced, and the water-blocking sheet 3b is moved downwardly by the slope. A large tension can be relieved by the action of feeding to. In addition, by attaching an air pressure gauge and an air pump to the valve 10 of the air bag 7 and injecting gas into the air bag when the water impermeable sheet is stretched in the opposite direction due to a rise in temperature, It is also possible to perform daily control of the tension applied to the seat. Therefore, the increase or decrease in tension caused by changes in temperature due to seasonal changes can be sufficiently relaxed by the action of the first stage, and even if greater tension relaxation is required, it is sufficient to meet the demand. be able to.

[0032]

INDUSTRIAL APPLICABILITY The present invention is a water-impervious sheet structure in which a water-impervious sheet is laid in a waste treatment plant as described above. This is an air bag that allows gas to flow in and out.When waste is dumped and the water-blocking sheet is heavy, the air-bag is pressed down from above by the water-blocking sheet and the internal gas is compressed. Is reduced and the tension is relieved by letting out the impermeable sheet to the lower side of the slope, and the volume of the airbag is greatly reduced by discharging the gas in the airbag to the outside. It is possible to prevent the sheet from breaking by letting out the water-blocking sheet downward so that the tension can be relaxed to a greater extent as compared with the means described in the above-mentioned JP-A-1-247609. That. Further, according to the second and sixth aspects of the present invention, by installing an air pressure gauge on the valve of the air bag, it becomes possible to always maintain a constant pressure using the air pump, and to manage the tension applied to the seat on a daily basis. be able to. In particular, in the present invention, the tension applied by the self-weight of the water-impermeable sheet is temporarily applied, but the stretched water-impermeable sheet due to the weight of waste can be reduced to approximately zero by discharging the gas in the air bag. , Is extremely effective as compared with the conventional water impermeable sheet. The construction method according to claims 4 and 5 is a suitable method because it is easy to arrange and fix the air bag. Claims 3 and 7
Since the air chambers described above are independent air chambers at predetermined intervals, a predetermined effect can be obtained by one air chamber even if the air chamber is flat, and safety can be improved.

[Brief description of drawings]

FIG. 1 is a plan view showing one embodiment of a water-blocking sheet structure according to the present invention.

FIG. 2 is a cross-sectional explanatory view in which the cross section taken along the line AA of FIG. 1 is made easy to understand.

FIG. 3 is an enlarged view of a shoulder portion in FIG.

FIG. 4 is a schematic view showing another embodiment of the airbag.

FIG. 5 is a schematic view showing still another embodiment of the airbag.

FIG. 6 is a schematic diagram showing another usage mode of an air bag in which two air bags are used side by side.

FIG. 7 is an enlarged view showing a shoulder portion in a state where gas is enclosed in an air bag.

FIG. 8 is an enlarged view showing a shoulder portion of the air bag in a state where gas is discharged.

[Explanation of symbols]

 1 Waste treatment plant 2 Base 3a Bottom water-blocking sheet 3b Slope water-blocking sheet 4 Shoulder 5 Small step 7 Air bag 8 Block 11 Void

Claims (7)

[Claims] 1. A water-blocking sheet structure having a water-blocking sheet laid on a construction surface such as a waste treatment plant, a reservoir, or a waterway, wherein a water-impermeable sheet is provided between a base of a shoulder portion of the water-impermeable sheet and the water-impermeable sheet. A water-blocking sheet structure comprising a hose and a valve, and an air bag in which gas can be freely taken in and out is interposed. 2. The waterproof sheet structure according to claim 1, wherein an air pressure gauge and an air pump are attached to the valve of the air bag. 3. The waterproof sheet structure according to claim 1, wherein the air bag is a tube or hose-like member in which air chambers are independently formed at predetermined intervals. 4. A hose and a valve are provided at the upper shoulder of the slope at the time of constructing an impermeable sheet on the slope and bottom of a waste treatment plant having slopes and bottoms, reservoirs, waterways, etc. Arrange an air bag that allows gas to be taken in and out, and lay a waterproof sheet of a specified width from above to cover the airbag, and join adjacent waterproof sheets together, and keep the waterproof sheet on the slope. A method of constructing a water-blocking sheet structure, characterized by embedding and fixing it in the ground with a block at the shoulder. 5. When installing a water blocking sheet on a slope or bottom of a waste treatment plant having slopes or bottoms, reservoirs, waterways, etc., gas can be freely taken in and out in the form of a tube or hose at the slope shoulders above the slopes. Arrange an air bag equipped with a hose and a valve in a state in which gas is removed, and lay a waterproof sheet with a predetermined width from above to cover the airbag, and join adjacent waterproof sheets together. At the same time, a water-impermeable sheet structure construction method is characterized in that a water-impermeable sheet on the slope is buried and fixed in the base at the shoulder by a block, and gas is injected into the air bag. 6. The method for constructing a water-blocking sheet structure according to claim 4, wherein an air pressure gauge and an air pump are attached to the valve of the air bag. 7. The method for constructing a water-blocking sheet structure according to claim 3, wherein the air bag is a tube or hose-like member in which air chambers are independently formed at predetermined intervals.