JPH076177B2 - Water stop method for artificial pond - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention aims to artificially store water, such as a landscaped pond in a golf course or a park, a regulating pond, and a pond for securing irrigation water. This is related to the water stoppage method for construction of artificial ponds.

[Conventional technology]

As shown in Fig. 4, a good quality soil 2 is laid on the original soil 1 and leveled, and the good quality soil 2
A sheet 3 such as a rubber sheet or a vinyl chloride sheet is laid on the top.

Although not shown, there is also a method of covering the high quality soil 2 with concrete or asphalt.

[Problems to be Solved by the Invention]

In the sheet construction method shown in FIG. 4, when a rubber sheet is used for this sheet 3, the sheet 3 may bulge after construction if air is not removed properly from the back side of the sheet.

When a vinyl chloride sheet is used as the sheet 3, it is cheaper and more economical than the case of the rubber sheet, but it is inferior in long-term stability in terms of material.

The water-stopping method based on concrete or asphalt is troublesome in processing joints and joints, and if this is incomplete or cracks occur due to drying shrinkage, a sufficient water-stopping effect cannot be expected.

In addition, with any of the above-mentioned construction methods, there is a problem in the deformation followability with respect to unequal subsidence assuming that the construction is performed on the embankment base.

The purpose of the present invention is to solve the disadvantages of the conventional example, long-term stability is excellent in deformation followability to uneven settlement, and it is an inexpensive artificial pond that can correspond to the sheet construction method using a vinyl chloride sheet in terms of construction cost. It is to provide the water stop method.

[Means for Solving the Problems]

The present invention, in order to achieve the above objects, mixed and stirred bentonite and high-quality soil, and formed a water blocking layer by compaction, and further formed a protective layer using crushed stone, crushed stone, gravel, etc. Alternatively, the gist is to form a protective layer by cement stabilization treatment in two layers and to provide a resin net between the protective layers.

[Action]

The water stop layer is formed by mixing and stirring bentonite and high-quality soil and rolling the mixture, and water stop is performed by utilizing the property that montmorillonite contained in bentonite swells when it comes into contact with water.

Therefore, in terms of quality, even if it receives repeated action of dry and wet due to the fluctuation of the water level, it is stable for a long period of time by repeating the swelling action each time, and can follow the deformation due to uneven subsidence of the ground.

Also, if you simply mix and stir bentonite and high-quality soil, and spread them evenly, the mixed layer that comes into contact with water will become sludge-like, and not only machines but also people will not be able to enter it. Since there is a protective layer on top of the water blocking layer, it will not be in such a state, and maintenance work such as roughening of the floor, which is necessary after construction, can be performed without any hindrance.

According to the present invention as set forth in claim 1, the protective layer is made of crushed stone, crushed stone, gravel, etc., and these crushed stone, crushed stone, gravel, etc. are excellent in permeability, so when the pond water enters after the artificial pond is completed, In addition, it allows moisture to reach the water stop layer below this protective layer, causing the swelling action of the water stop layer, and when performing maintenance work such as roughening of the bottom that is necessary after construction. Moreover, since the grains are large, handling is relatively easy, and as the bottom of the pond, living organisms can live in easily, and the appearance can be made to look like a real pond.

According to the present invention as set forth in claim 2, the protective layer is formed by dividing the protective layer by cement stabilization treatment into two layers, and the resin net is provided between the protective layers, as amended in the present amendment. Since the protective layer by cement stabilization treatment is divided into two layers and the resin net is inserted between the layers, cracks in the protective layer can be prevented and the durability period can be extended.

〔Example〕

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a vertical sectional side view showing a first embodiment of a water stopping method for an artificial pond of the present invention, and FIG. 2 is a plan view of the same.

Reference numeral 4 in the drawing is an artificial pond, and the shape of the pond 4 is not limited, but the illustrated example is a rectangular shape.

First, as a process of excavating and shaping the artificial pond 4, the artificial pond 4 is excavated into a predetermined shape with a backhoe or another excavator.

In this case, the excavation height of the pond bottom is the height obtained by subtracting the thicknesses of both the protective layers 9 and 10 and the water stop layer 8 formed by a bentonite mixed layer, which will be described later, from the finished surface. In addition, the slope will be a gentle slope of 1: 6 or less, and the slope shoulder will be finished with a water level +20 cm rise as a guide.

Then, the high-quality soil (top soil) that has been stocked in advance is transported to the site and evenly spread to a thickness of 30 cm using a bulldozer.

At this time, the structure around the structures such as the sludge sluice, the wastewater tower 6, the respective pipes 7, the circulation pump pit (not shown), etc. should not be laid evenly on the soil, but should be stocked aside. It shall be spread on the bentonite and mixing agitator.

A vinyl chloride pipe was used for the pipe 7, and an expansion joint was incorporated in the joint portion.

Bentonite is sprayed as the next step.

Regarding the amount of bentonite sprayed (mixing ratio with good quality soil), an indoor soil test was conducted in advance and the result was 1 x
The blending ratio of bentonite (usually about 5% to 15% with respect to the wet weight of soil) that can obtain a hydraulic conductivity of 10 ^-6 cm / sec or less is determined.

When applying such bentonite, one pack (90
Calculate the spraying area per 0 kg bagging), draw a line with lime on the pond surface where the leveling of high quality soil has been completed, and 1 block = 1
Blocks are divided into packs.

As an example of spraying, when 8% of bentonite is added to good quality soil (wet weight γd = 1.8t / m ³ ) with a thickness of 30cm, the spraying area per pack is as follows: 0.9 ÷ (1.0 × 0.3 × 1.8 × 0.08) = 20.8m ² Therefore, the block division should be 4.5m × 4.5m.

After arranging the bentonite in each block in this way, it is sprayed with a backhoe and spread to a uniform thickness manually.

Next, high-quality soil and bentonite are mixed and stirred by a stabilizer. For places where mixing and stirring with a stabilizer is difficult, use a backhoe. As a general rule, stirring is performed twice, ie, primary stirring and secondary stirring, and the degree of mixing is checked visually.

And when the mixing and stirring by the stabilizer is completed,
Perform bull-dozer training on the land and roll it with rollers.

In this way, bentonite and good quality soil are mixed and stirred,
And the water stop layer 8 formed by rolling is formed.

After the compaction of the bentonite mixed layer is completed and the water stop layer 8 is formed, a protective stone 9 is formed by laying a slag on the bentonite mixed layer with a backhoe manually.

For the formation of the protective layer 9, crushed stone, gravel, or on-site scrap may be used instead of the crushed stone.

It should be noted that the work from the spraying of bentonite to the formation of the protective layer 9 should be carried out at once in a fine weather, because the bentonite causes a swelling action when it rains on the way and the subsequent work becomes impossible. is there.

FIG. 3 shows a second embodiment of the present invention. The protective layer 10 formed on the water blocking layer 8 is formed by a cement stabilization treatment such as stirring cement milk and earth and sand to obtain soil cement. .

In this case, the protective layer 10 by cement stabilization treatment shall be divided into two layers, and the resin mesh between layers shall be used.
To prevent cracking of the protective layer 10.

〔The invention's effect〕

As described above, the water stop method for the artificial pond of the present invention utilizes the property that the water stop layer is formed by mixing and stirring bentonite and high-quality soil, so that the montmorillonite contained in the bentonite swells when it comes into contact with water. Water is stopped in this way, and even if it receives repeated actions of dryness and humidity due to fluctuations in water level, it repeats the swelling action each time and is stable for a long period of time, and can follow deformation due to uneven subsidence of the ground.

Also, by providing a protective layer on this water blocking layer, it is possible to easily perform maintenance work such as roughening of the bottom by draining water from the pond after construction without damaging the water blocking layer. .

Further, compared to the waterproof construction method using a sheet and the waterproof construction method based on asphalt and concrete, the construction can be performed easily and inexpensively without taking troublesome means.

Also, with regard to the shape of the pond, there is also the advantage that ponds of various shapes, whether circular or rectangular, can be easily made if the slope of the slope is gentle.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a first embodiment of a water stopping method for an artificial pond of the present invention, FIG. 2 is a plan view of the same as above, FIG. 3 is a vertical sectional side view showing a second embodiment, and FIG. It is sectional drawing of the principal part which shows a prior art example. 1 …… Original soil, 2 …… Good quality soil 3 …… Sheet, 4 …… Pond 5 …… Drainage mud, 6 …… Drainage tower 7 …… Piping, 8 …… Water stop layer 9,10 …… Protective layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Keiichi Tsutsumi Inventor Keiichi Tsutsumi 1-3-8 Moto-Akasaka, Minato-ku, Tokyo Akasaka DK Building 4F Kashima Construction Co., Ltd. Kanto Branch (72) Inventor Naoyuki Tsuchiya Tokyo Port Moto Akasaka 1-3-8 Akasaka DK Building 4F Kashima Construction Co., Ltd. Kanto Branch (72) Inventor Jun Fujita Motoaka Akasaka 1-3-8 Akasaka DK Building 4F Kashima Construction Co., Ltd. Company Kanto Branch (72) Inventor Tadashi Sakita 2-7-12 Mita, Minato-ku, Tokyo Tokubun Building TIC Inc. (72) Inventor Tomonori Nagaoka 1-10 Iwamotocho, Chiyoda-ku, Tokyo No. 5 within Kunimine Industry Co., Ltd. (56) Reference JP-A-63-125717 (JP, A)

Claims (2)

[Claims] 1. Bentonite and high-quality soil are mixed and stirred, and then compacted to form a water-stop layer, and on top of that, quarry stone, crushed stone,
A method of stopping water in an artificial pond, which is characterized by forming a protective layer using gravel. 2. Bentonite and high-quality soil are mixed and stirred, and then compacted to form a water blocking layer, and a protective layer formed by cement stabilization treatment is further divided into two layers, and a resin layer is provided between the protective layers. A water blocking method for an artificial pond, which is characterized by the provision of a net.