JPH1018362A - Underground water storage tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a collapse of a peripheral wall by covering a water storage space, which is formed in an underground recessed shape and whose peripheral wall surface inclines in an upward opening shape, with a water nonpassible water shielding sheet, providing an aggregate composed of a large number of heaping-up members having water storage voids through the water shielding sheet, arranging a water passable partition wall on the periphery of the aggregate, and providing a water passable layer in a space with the peripheral wall surface and a water permeable layer on the aggregate and the water passable layer. SOLUTION: An underground water storage tank A has a water storage space 1, and its peripheral wall surface 11 inclines in an upward opening shape as much as possible by considering an angle of repose of earth. A bottom wall surface 12 and the peripheral wall surface 11 are covered with a water nonpassible water shielding sheet 2, and nonwoven fabric 21 is arranged on it, and an aggregate 3 is loaded. This aggregate 3 is composed of a vertically stage-stacking heaping-up members 4, and the respective ones have water storage voids, and a single large space is formed as a whole. A partition wall 5 is arranged on the periphery of the aggregate 3, and water passable holes 51 are penetratingly formed, and a water passable layer 6 composed of small solid materials is provided in the space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an underground water storage tank, in particular, a load applied to a permeable layer disposed over a water storage space.
The present invention relates to an underground water storage tank that can be received by an assembly composed of a number of stacking members provided in the water storage space.

[0002]

2. Description of the Related Art An underground water storage tank of this kind is described in Japanese Patent Publication No. Hei 4-26648. In the underground water storage tank described in this publication, the surrounding wall surface of the water storage space formed in a concave shape in the ground has an angle close to vertical, and a set of stacking members loaded in the water storage space A gravel layer is loaded in the gap between the body and the peripheral wall surface, and the gravel layer serves as a water-permeable side wall. In this underground water storage tank, the peripheral wall surface of the water storage space is raised at an almost vertical angle because the stacking members are arranged vertically and horizontally and stacked vertically to form the aggregate. This is considered to be to improve the accommodation of the aggregate in the water pool space.

[0003]

However, if the surrounding wall of the water storage space has an angle close to vertical as in the underground water storage tank described in the above-mentioned publication, the surrounding wall may be easily formed depending on soil properties. Due to the flow of groundwater or the flow of rainwater that has infiltrated into the ground from the surface of the ground, causing the formation around the reservoir space to loosen. Even if it is supported from the inside by the gravel layer, there is a possibility that the surrounding wall surface may collapse.

Therefore, it is effective to prevent the collapse of the peripheral wall surface by stabilizing the peripheral wall surface by inclining the peripheral wall surface of the water storage space at an angle that does not collapse.
However, when the peripheral wall surface of the water storage space is inclined at such an angle that it does not collapse, the outer surface of the assembly formed by arranging the stacking members vertically and horizontally and stacking up and down and the surrounding space are formed. Since a large space is formed between them, how to process the space becomes a problem.

The present invention has been made in view of the above problems, and can fill a large space formed between the outer surface of the above-mentioned assembly and the above-mentioned surrounding space while ensuring water permeability. Moreover, an object of the present invention is to provide an underground water storage tank capable of effectively preventing a collapse of the peripheral wall surface by applying a downward load to the peripheral wall surface. Also,
An object of the present invention is to provide an underground water storage tank in which the above-mentioned assembly can be easily stored even if the peripheral wall surface of the water storage space is inclined.

[0006]

SUMMARY OF THE INVENTION An underground water storage tank according to the present invention has a bottom wall and a bottom wall in a water storage space which is concavely formed in the ground and whose peripheral wall is inclined upwardly. The continuous peripheral wall is covered with a water-impermeable sheet having no water permeability, and an aggregate including a number of stacking members having a space for water reservoirs arranged vertically and horizontally and stacked vertically. The partition wall is provided on the bottom wall surface via the water-blocking sheet, and a partition wall having water permeability that is vertically raised is provided around the assembly, and is provided between the partition wall and the peripheral wall surface. In this space, a water-permeable layer made of a collection of small solids is provided, and a water-permeable layer is provided on the aggregate and the water-permeable layer.

According to this underground water storage tank, the fact that the peripheral wall surface of the water storage space formed concavely in the ground is inclined upward and upward not only contributes to the stabilization of the peripheral wall surface, The load of the water-permeable layer, which is a collection of small solids disposed in the space between the partition wall and the peripheral wall surface, is applied in a direction to compact the peripheral wall surface, and the peripheral wall surface becomes more stable. Further, between such a water-permeable layer and the above-mentioned aggregate, since a partition wall which is vertically raised around the aggregate is provided, by the partition wall,
Small solids, such as crushed stones, forming the water-permeable layer do not enter the water-reserving space inside the assembly, and the stacking member is partially fixed by the small solids to which force is applied. At the same time, and at the same time, when a person walks or a car runs on the permeable layer, the horizontal load applied to the assembly through the permeable layer is dispersed by the partition wall. As a result, it is possible to prevent the above-mentioned aggregate from collapsing to its side or being displaced. In addition, the partition wall also serves to improve the accommodation of the assembly.

In this underground water storage tank, rainwater that has fallen on the surface of the ground is introduced through the permeable layer into the cavities for water collection and the permeable layer provided in the assembly, and is transmitted to the permeable layer. The infiltrated rainwater is further introduced and stored in the gap by the water permeability provided in the partition wall.

[0009] In the underground water storage tank of the present invention, the end of the surface water introduction channel extending through the water-blocking sheet and the water-permeable layer is disposed in the water gap, and the water is provided in the water storage space. It is desirable to have a drainage channel for draining water collected in the storage space. According to such an underground water storage tank, surface water such as rainwater collected in a gutter can be directly introduced into the water gap provided in the aggregate via the surface water introduction path. . Also,
The water accumulated in the water storage space can be drained through a drainage channel as needed. Therefore,
For example, when the water level of an urban river is rapidly rising due to heavy rain, rainwater is directly introduced from the gutter through the surface water introduction channel into the water gap, and the discharge of rainwater from the gutter to the river is reduced. It is possible to reduce the water level of the river and discharge the water that has accumulated in the water gap into the river gradually through the drainage channel. Flooding can be prevented beforehand.

[0010] In the present invention, it is desirable that each of the stacking members forming the above-mentioned aggregate is a synthetic resin skeleton structure. According to this, a large volume of the water storage space can be ensured by the above-mentioned assembly, so that a large amount of water can be stored. In addition, since the stacking member is made of the above-described synthetic resin skeleton structure, the weight of the stacking member can be easily reduced.

In the present invention, it is preferable that a drain groove is provided at a bottom of the water storage space, and a start portion of the drain channel is connected to the drain groove. According to this underground water storage tank, the water accumulated in the sump space is drained through the drainage ditch and the drainage channel connected thereto, so that all the water in the sump space is drained to generate residual water. It is easier to avoid.

In the present invention, it is preferable that the stacking member is installed so as to straddle the drain groove. According to this, the inflow of water into the drainage ditch is not hindered by the stacking member.

In the present invention, the small solids forming the water-permeable layer are preferably small stones such as crushed stones, gravel, and cobblestones. According to this, it is easy to obtain a small solid.

In the present invention, it is preferable that the permeable layer is a soil layer. According to this, a lawn can be vegetated or a parking lot can be constructed on the soil layer.

Further, in the present invention, the partition wall can be constituted by combining a plurality of flat plates,
In this case, it is also possible to use a plastic material such as FRP, whereby the weight of the partition wall can be reduced, and there is an advantage that transportation and construction are facilitated.

[0016]

1 is a partially omitted longitudinal sectional view schematically showing an underground water storage tank A according to an embodiment of the present invention. FIG. 2 is an enlarged view showing a main part of an assembly 3. FIG. 3 is a plan view schematically showing the underground water storage tank A.

The underground water storage tank A has a water storage space 1 which is dug down into the ground so as to be recessed into the ground. In the water storage space 1, the peripheral wall surface 11 is inclined upwardly so as to have an elevation angle as small as possible in consideration of the angle of repose of the earth and sand forming the stratum.
The bottom wall surface 12 of the water reservoir section 1 and the peripheral wall surface 11 continuous with the bottom wall surface 12 are covered with a water-impermeable sheet 2 having no water permeability.
1 is deployed. Sheets such as a vinyl chloride resin sheet, a rubber sheet, and a pocket ethylene resin sheet can be used as the water-impervious sheet 2.

The aggregate 3 is mounted on the bottom wall 12 of the water storage space 1 via the water-blocking sheet 2 and the nonwoven fabric 21. The assembly 3 is composed of a large number of stacking members 4 which are arranged horizontally in the vertical and horizontal directions and are vertically stacked. These stacking members 4 are made of a synthetic resin skeletal structure, each of which has a cavity for a water reservoir,
These voids communicate with each other to form one large space as a whole.

A partition wall 5 made of concrete, which stands vertically, is provided around the assembly 3. A large number of water holes 51 are formed in the partition wall 5 so as to penetrate therethrough, and water is given to the partition wall 5 by the water holes 51. In the example shown in the figure, partition walls 5, 5 which are vertically raised are also provided at two places in the center of the water storage space 1, and the partition walls 5 divide the assembly 3 into two right and left parts. Have been. Then, a water-permeable layer 6 composed of a collection of small solids is provided in the space between the partition wall 5 and the peripheral wall surface 11 and the space between the two partition walls 5 and 5 at the center.
Has been deployed. The water-permeable layer 6 in the illustrated example is formed by loading crushed stone into the space. This water layer 6
Can be formed from pebbles such as gravel or cobblestone.
Further, a water permeable layer 7 is provided on the assembly 3 and the water permeable layer 6.
Are arranged. The permeable layer 7 is formed by laying earth and sand, and a lawn is vegetated using the permeable layer 7. It is also possible to form a car parking lot on the permeable layer 7. In addition, the partition wall 5 may be made of porous concrete, and the partition wall 5 may be provided with water permeability. In addition, the thickness of the partition wall 5 is set to have a strength that can withstand the load applied to the assembly 3 and the load applied to the water-permeable layer 6 in a comprehensive manner. In addition, the partition wall 5 can be made of plastic such as FRP, whereby the weight of the partition wall can be reduced, and there is an advantage that transportation and construction are facilitated.

The water-impervious sheet 2 and the water-permeable layer 6 are inserted into the water-storage space formed by the stacking member 4.
Is arranged at the end of the surface water introduction channel 8 extending therethrough. The surface water introduction channel 8 is provided for introducing rainwater collected from a gutter provided on the sidewalk of a city park (not shown) or rainwater flowing out of a tennis court or the like into the water gap. . Further, a drain groove 91 for draining water collected in the water gap is provided at the bottom of the water storage space 1. The start of the drain passage 9 is connected to the drain groove 91. Have been. The drainage channel 9 can be formed by embedding a synthetic resin pipe, and a control valve 92 is interposed in the drainage channel 9.

In the underground water storage tank A described above, the wall 13 surrounding the water storage space 1 is not always necessary. However, when it is necessary to strengthen or stabilize the ground, the wall 13 may be formed of a discarded concrete layer having a predetermined thickness.

FIGS. 4 and 5 show a specific example of the stacking member 4. FIG. 4 is a schematic perspective view of the stacking member 4 as viewed obliquely from above, and FIG. FIG. 2 is a schematic perspective view when viewed obliquely from above.

The stacking member 4 is a skeletal structure integrally formed of a synthetic resin such as a polypropylene resin or a polyvinyl chloride resin. That is, the stacking member 4 is provided with an equal length leg rod 43 formed of a hollow cylinder at each of the four corners 42 of the square annular connecting bone 41. These four legs 43 are arranged in parallel with each other, and these legs 43 are connected to each other by the connection bone 41. The connecting bone 41 is provided with ribs 47 extending in a diagonal direction. Each leg 43 and the connecting bone 41 intersect at a right angle, and a reinforcing bracket 46 is provided between each leg 43 and the connecting bone 41. This reinforcing bracket 46
Is the load applied to the leg 43 and the connecting bone 41
It helps to prevent that the perpendicularity with is lost.

A fitting portion 44 is provided at one end of each leg 43.
Is provided on the other end of the leg 43, and the fitting portion 44
A fitted portion 45 having a shape and dimensions that can be fitted to the fitting portion 45 is provided. In this embodiment, the connecting bone 41 is formed by a plate-like frame, and only the fitted portion 45 of the leg 43 projects to one side of the plate-like frame, and the portion of the leg 43 excluding the fitted portion 45 is formed. Project from the other surface of the plate-shaped frame.

The length of the leg 43 in the stacking member 4 is 20 to 80 cm, preferably 30 to 50 cm.
cm is appropriate, and the outer diameter of the leg 43 is 2 to 5 cm.
cm is preferred. The length and thickness of the leg 43 are determined to appropriate values depending on the material, strength, shape, and the like. Both the vertical and horizontal dimensions of the connecting bone 41 are 30 to 80 cm
However, it is not necessarily limited to this value depending on the material, strength, shape and the like. Stacking member 4
Is preferably made into a cube or a shape similar to the cube as a whole.
The workability when arranging in the vertical and horizontal directions or stacking vertically is improved, and the space in the space surrounded by the partition wall 5 is improved.

FIG. 2 shows a form in which the stacking members 4 are vertically stacked. That is, as shown in FIG. 2, each of the four leg rods 43 of the one stacking member 4 is located between the two stacking members 4, 4 stacked vertically in the assembly 3. The fitting portions 44 are respectively fitted to the fitted portions 45 of the four leg rods 43 of the stacking member 4 at the other stage. In the stacking members 4 arranged in the vertical and horizontal directions, the connecting bones 41 abut each other in the vertical and horizontal directions, and are adjacent to each other in the vertical and horizontal directions. Between the four stacking members 4... Adjacent to each other, four leg bars 43.
Are connected by a connector (not shown) for keeping the relative position of... Constant. Of the many stacking members 4 arranged at the lowermost stage, the one arranged at the place where the drain groove 91 is formed is installed across the drain groove 91 as shown in FIG. . Further, a lid is attached to each of the stacking members 4 at the uppermost stage, and the opening of the stacking member 4 is closed by the lid. The permeable layer 7 is formed on the lid.

In the above-described underground water storage tank A, when the partition wall 5 is formed in a rectangular shape as shown in FIG. 3, a plurality of flat concrete panels may be formed by abutting at right angles or by a flat plate. By doing so, the workability of the partition wall 5 is improved. When the partition walls 5 are joined at right angles to each other and joined to each other, as shown in FIG. 6, the abutting portions of the partition walls 5 are sandwiched by a pair of corner connecting tools 101 and 102 from both front and back sides, and they are joined. May be fastened with fasteners 100 such as bolts and nuts that have been inserted through. In addition, partition wall 5
Fig. 7
As shown in the above, the abutting portion may be sandwiched between a pair of flat connecting members 103 and 104 from both the front and back sides, and these portions may be fastened with fasteners 100 such as bolts and nuts inserted through the partition wall 5. .

In the above-mentioned underground water storage tank A, since the peripheral wall surface 11 of the water storage space 1 is inclined upward and upward, the peripheral wall surface 11 is formed as compared with the case where the peripheral wall surface 11 is formed vertically. Itself is stable. In addition, a water-permeable layer 6 between the partition wall 5 and the peripheral wall surface 11
Is applied in the direction of compacting the peripheral wall surface 11, so that the peripheral wall surface 11 is further stabilized. In addition, since the partition wall 5 that is vertically raised around the aggregate 3 is provided between the water-permeable layer 6 and the aggregate 3, the partition wall 5 allows the water to flow through. The small solids such as crushed stones forming the layer 6 are prevented from entering the water collecting space inside the aggregate 3 and closing the space, and at the same time, a person walks on the water permeable layer 7. The horizontal load applied to the assembly 3 via the water permeable layer 7 when the vehicle runs or the vehicle runs is dispersed and received by the partition wall 5, so that the assembly 3 collapses to the side. Things don't happen.

In the underground water storage tank A, the rainwater that has fallen on the surface of the ground is introduced through the permeable layer 7 into the water gaps provided in the assembly 3 and the permeable layer 6, The rainwater that has infiltrated the layer 6 is introduced into the gap through the water holes 51 provided in the partition wall 5 and stored. Surface water such as rainwater collected in a gutter or the like is directly introduced into the gap via the surface water introduction channel 8. However, when the surface water contains solids such as dead leaves and earth and sand, a solid separation tank, a filtration tank, a sedimentation tank and the like are provided in front of the underground water storage tank A to remove the solids. It is desirable to be able to separate. By doing so, clean water free of solid matter accumulates in the water gap. The water collected in the water gap can be drained through the drain 9 as needed.

Such an underground water storage tank A can be used to avoid a situation in which the water level of an urban river suddenly rises and floods when it is hit by heavy rainfall. For example, the pool 1 is emptied in advance by a warning of a torrential rain, and while the water level of the river is rising due to the torrential rain, a part of the rainwater flowing over the surface of the ground and flowing into the river is used as the water. If the water in the reservoir space 1 is allowed to flow into the reservoir space 1 and temporarily stored, and the water level of the river falls due to the torrential rainfall, the water in the reservoir space 1 is discharged to the river. Floods due to ascent can be avoided. When an emergency such as a fire is required, the water stored in the water storage space 1 can be pumped up and used as fire protection water. Usually, the sump space 1
Can be used for watering plants and the like, and for that purpose, it is preferable to separately draw out a water fetching port from the water storage space 1.

Further, like the above-mentioned underground water storage tank A, the above-mentioned assembly 3 is divided into right and left, and the left and right
If a water-permeable layer 6 made of a collection of small solids such as crushed stones is formed in the space sandwiched between the partition walls 5 and 5, the scale of one aggregate 3 is reduced to an appropriate scale. So that
The partition wall 5 not only ensures the effect of fixing the stacking member 4 so as not to be displaced,
The workability of the stacking member 5 is also improved. Also, when water moves from the sump gap of the left aggregate 3 to the sump gap of the right aggregate 3 through the water passage layer 6 between the partition walls 5 and 5. The water passage layer 6 exerts a water purifying function as a filter. For this reason, if the water-permeable layer 6 is formed of charcoal or a special mineral, the water taken out from the water-storage space of the right-side assembly 3 can be effectively used according to the degree of purification. Will be possible.

[0032]

The underground water storage tank according to the present invention does not collapse because its peripheral wall surface is stable even though its peripheral wall surface is inclined. In addition, a situation in which the aggregate collapses due to the load does not occur. In addition, since the partition wall stands upright, the collection of the aggregate is improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view schematically showing an underground water storage tank according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing a main part of the assembly.

FIG. 3 is a plan view schematically showing an underground water storage tank.

FIG. 4 is a schematic perspective view when the stacking member is viewed obliquely from above.

FIG. 5 is a schematic perspective view when the stacking member is turned over and viewed obliquely from above.

FIG. 6 is an explanatory view showing a coupling structure of a partition wall.

FIG. 7 is an explanatory view showing another connection structure of the partition wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS A Underground water storage tank 1 Water storage space 2 Impermeable sheet 3 Assembly 4 Stacking member 5 Partition wall 6 Water layer 7 Permeable layer 8 Surface water introduction channel 9 Drainage channel 11 Peripheral wall surface 12 Bottom wall surface 91 Drainage groove

Claims (8)

[Claims] 1. A bottom wall in a water storage space which is formed so as to be recessed in the ground and whose peripheral wall is inclined upward and upward, and the above-mentioned peripheral wall which is continuous with the bottom wall does not have water permeability. An aggregate consisting of a number of stacking members that are covered with a water sheet, are arranged in the vertical and horizontal directions, and are stacked vertically are provided on the bottom wall surface via the water-impervious sheet. And, around this assembly, a vertically rising partition wall having water permeability is provided,
A water-permeable layer made of a collection of small solids is provided in a space between the partition wall and the peripheral wall surface, and a water-permeable layer is provided on the aggregate and the water-permeable layer. And underground water tank. 2. An end portion of a surface water introduction passage extending through the water-impervious sheet and the water-permeable layer is disposed in the water-holding space, and is collected in the water-holding space. The underground water storage tank according to claim 1, further comprising a drainage channel for draining water. 3. The underground water storage tank according to claim 1, wherein each of the stacking members forming the assembly is a skeleton structure made of synthetic resin. 4. The underground water storage tank according to claim 2, wherein a drainage groove is provided at a bottom of the water storage space, and a start portion of the drainage channel is connected to the drainage groove. 5. The underground water storage tank according to claim 3, wherein the stacking member is installed across the drain groove. 6. The small solid material forming the water-permeable layer,
The underground water storage tank according to claim 1, which is a pebble such as crushed stone, gravel, and cobblestone. 7. The underground water storage tank according to claim 1, wherein said permeable layer is a sediment layer. 8. The underground water storage tank according to claim 1, wherein said partition wall is formed by combining a plurality of flat plates.