JP2005113435A - Rainwater infiltrating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rainwater infiltrating device capable of increasing water permeability in the ground, reducing an installation space in the horizontal direction in the ground, installable even in a narrow place, freely deformable in the ground, capable of flexibly coping with a condition of an installation place, and capable of particularly preventing ground subsidence by generation of a city type flood and depletion of underground water. <P>SOLUTION: This rainwater infiltrating device is arranged in a shaft reaching a water permeable layer 9 drilled in the ground, and is made of a water permeable sheet, and is composed of a longitudinally long bag body 2 of filling a glass cullet 3 being a crushed stone-like material inside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rainwater infiltration device for infiltrating rainwater into the ground.

  In recent years, due to urban development and residential land development, the amount of rainwater penetrating into the ground has decreased as the surface of the surface has increased. For this reason, when it rains, most of the rainwater flows into the river without penetrating into the ground, the amount of water in the river increases rapidly, the water level rises, and there is a risk of flooding during heavy rain. In particular, urban flooding has increased in recent years, when heavy rains frequently occur in cities.

  In addition, since the amount of water penetrating into the ground is small, if the day when it does not rain continues, plant growth will be hindered, and the amount of water in rivers and lakes will decrease, making it difficult for living organisms such as fish to live. There is also a risk that the ecosystem will be destroyed. In addition, groundwater may be depleted and land subsidence may occur.

Therefore, as a means of infiltrating rainwater into the ground, a drainage pipe for flowing rainwater is provided on residential land, etc. Yes. For example, the rainwater penetrating rod surrounds at least a tubular portion of the wall surface portion of the wall surface portion in which a plurality of first through holes are formed in the wall surface portion and a lid is attached to the upper opening portion. A space forming member having a shape that forms a space around the wall surface portion and having a plurality of second through holes, and surrounding the space forming member to allow rainwater to permeate. There is a thing provided with a transparent sheet material (for example, refer to patent documents 1).
JP 2000-282554 A

  In the seepage trough disclosed in Japanese Patent Laid-Open No. 2000-282554, the rainwater that has entered the rainwater seepage trough passes through the first through hole and bottom hole of the spear body, and then the space of the external space forming member and the second Through the outer sheet material, through the outer sheet material, through the sand layer, and infiltrate the surrounding soil. The surface area of the wall, the water pressure due to the water level in the rainwater infiltration basin, the surrounding soil quality, etc.

  Such seepage ridges are mostly installed in shallow parts from the ground surface, and this part is a low permeability layer. For this reason, there is a possibility that the water permeability is low and the function of the permeation ridge cannot be exhibited sufficiently. In order to increase the water permeability, it is conceivable to increase the surface area of the wall of the seepage trough, but in this way, the diameter of the seepage trough increases and a large installation space is required in the horizontal direction.

  In order to eliminate the inconvenience of the conventional example, the invention according to claim 1 is arranged in a vertical hole reaching a water permeable layer drilled in the ground, made of a water permeable sheet, and crushed stone inside It is characterized by comprising a vertically long bag filled with a shape.

  According to the first aspect of the present invention, since the bag body filled with crushed stone-like material is embedded in the ground and is formed in a vertically long shape, the bag body reaches the water permeable layer, and the rainwater flowing into the bag body is excellent. It penetrates into the underground permeable layer. Further, since the bag body is formed vertically as described above, it does not take a horizontal installation space and can be installed in a narrow place. Furthermore, since the bag body is made of a sheet and has flexibility, it can be freely deformed and can flexibly respond to the conditions of the installation location.

  The invention according to claim 2 is characterized in that the crushed stone is glass cullet or crushed stone.

  According to the second aspect of the present invention, when the crushed stone is made into a glass cullet regenerated by pulverizing a glass bottle, the acid rain is neutralized by the alkalinity of the glass, and depending on the thickness of the glass cullet, it is alkalized. And has the ability to adjust ph. Moreover, since this ph adjustment ability has durability, it can prevent that surrounding soil acidifies over a long period of time.

  The invention described in claim 3 is characterized in that the crushed stone-like material to be filled in the bag body is laid with finely pulverized material in the upper layer portion.

  According to the third aspect of the present invention, it is possible to prevent soil and the like from entering the bag body from above by laying finely crushed crushed stones on the upper layer of the bag body, preventing clogging, It is possible to prevent the penetration ability from being lowered.

  The invention according to claim 4 is characterized in that the bag body filled with the crushed stone-like material is disposed below the seepage trough buried in the ground.

  According to the fourth aspect of the present invention, the bag body filled with the crushed stone-like material is installed below the seepage trough, so that the permeation of the place where the seepage trough is installed can be achieved even if the seepage trough has poor water permeability. The rate of water can be increased, and rainwater does not overflow from the seepage during rain, and the water retention rate of the soil can be increased.

  Since the rainwater infiltration device of the present invention is formed vertically, it reaches the water permeable layer in the ground and can increase the water permeability. In addition, since the installation space in the horizontal direction is small, it can be installed in a narrow place. Furthermore, since the bag body is flexible, it can be freely deformed and can flexibly meet the conditions of the installation location.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal front view showing a first embodiment of a rainwater infiltration device according to the present invention. A rainwater infiltration device 1 according to the present invention is made of a water-permeable sheet and has a vertically long bag body 2 and an interior of the bag body 2. It is comprised with the crushed stone substance by the glass cullet 3 with which it fills.

  If the material of the bag body 2 is water permeable, for example, chemical fibers such as polyethylene and polypropylene, cotton non-woven fabric, metal mesh, and the like may be considered, and the diameter is about 300 mm as an example.

  As the crushed stone, a crushed stone obtained by pulverizing a rock generally called a crushed stone may be used. In the present invention, a glass cullet 3 crushed and washed by a glass bottle is employed. The particle size of the glass cullet 3 is, for example, about 5 mm to 3 mm.

  And the glass cullet 3 of the said particle size is filled in the bag body 2, and the sand-like glass cullet 4 further finely grind | pulverized in the upper surface part of the bag body 2 is packed instead of sand.

  Next, a method for installing the rainwater infiltration device 1 in the ground will be described. First, an excavator or the like is used to excavate a vertically long hole having a diameter of about 250 mm and a depth of about 2,300 mm, the lower part of the bag body 2 is inserted into the hole, and a device such as a hopper is used. While the glass cullet 3 is put into the bag body 2, the bag body 2 is embedded in the hole.

  When the upper surface of the glass cullet 3 thrown into the bag body 2 approaches the ground level, sand or a finely crushed sandy glass cullet 4 is spread on the glass cullet 3.

  Then, the mouth of the bag 2 is closed and the upper opening is closed at the ground level. Since this rainwater infiltration device is vertically long, it does not require a horizontal installation space and can be installed in a narrow place.

  In this state, rainwater that has flowed into the bag body 2 from above during rain passes through the gap between the glass cullets 3 in the bag body 2 and permeates the bag body 2 and penetrates into the surrounding ground. In this case, since the glass cullet 3 has the alkalinity of the glass, it is neutralized to be alkaline when passing through the gap between the glass cullet 3 even if the rainwater is acidic.

  Below, the experimental result regarding the ph adjustment ability of the acid rain of the glass cullet 3 is shown. First, simulated acid rain is adjusted. This simulated acid rain is caused by sulfate ions (77.4 μeq / L), chloride ions (202.2 μeq / L), nitrate ions (24.65 μeq / L), and sodium ions (15 μeq / L). The pH was adjusted to 4.73.

  The first experiment is about the acid rain ph adjusting ability due to the difference in the amount of glass cullet deposited. In order to examine the change in acid rain ph adjusting ability due to glass cullet, the cullet is placed in a glass column with an inner diameter of 1.2 cm. The pH was measured when 60 cm of simulated acid rain was allowed to flow down at a rate of 0.77 mL per minute.

  The experimental results are shown in FIG.

  According to this, the simulated acid rain of ph 4.73 was neutralized even at a cullet thickness of 1 cm, resulting in ph 7.34. At a thickness of 5 cm, the pH shifted considerably to ph9.40.

  The second experiment was about the durability of the ph adjusting ability of the glass cullet. The glass cullet was packed 5 cm into the glass column, and ph was measured when 600 mL of simulated acid rain was caused to flow down.

  The experimental results are shown in FIG.

  According to this, it was ph 9.60 at the beginning of the acid rain flow, but decreased to ph 6.58 at the time of 200 mL flow. However, after that, the change of ph was not observed and it was maintained at about ph 6.00. 600 mL in this experiment corresponds to 5,300 mm of rainfall, 3.1 times the average annual rainfall in Japan, and was found to be durable for almost three years.

  The third experiment is about the amount of glass cullet soaked and the change in ph. 100 g, 200 g and 300 g of glass cullet with a particle size of 5 mm are immersed in 1 liter of simulated acid rain, and the change in ph at that time is measured. did.

  The experimental results are shown in FIG.

  According to this, the change in ph when immersing glass cullet in 1 liter of simulated acid rain increases the ability to adjust ph in proportion to the amount of cullet soaking up to about ph 6.46 at cullet 200 g or more. Neutralized. This value is comparable to normal rainwater ph. Moreover, it was found that the ph adjusting ability was equilibrated to a constant value in about 2 days after immersing cullet.

  And since this rainwater infiltration apparatus 1 can reach the permeable layer which the lower part of the bag body 2 is a groundwater layer, a water permeability can rise and it can also prevent the depletion of groundwater. Furthermore, since the glass cullet 3 has water retention, it maintains moisture in the soil even when the surface is dry, and provides moisture to the surrounding ground when there is little rainfall.

  Moreover, since finely crushed sandy glass cullet 4 is laid on the upper part, the infiltration of earth and sand into the bag body 2 is prevented, the internal glass cullet 3 is not clogged, and water permeability is maintained for a long time. It can be secured.

  FIG. 2 shows a second embodiment in which a seepage trough 5 is coupled to the upper portion of the bag body 2 into which the glass cullet 3 is charged, and a plurality of water passage holes 6 are appropriately formed in the seepage trough 5. The adjacent seepage troughs 5 are connected to each other by a culvert rainwater pipe 7.

  In this case, when there is precipitation that exceeds the penetration capacity of the seepage trough 5 or the drainage capacity of the rainwater pipe 7, rainwater collected in the seepage trough 5 flows down into the bag body 2 below. Since it passes through the inside glass cullet 3 and penetrates into the surrounding ground, the water permeability can be increased and rainwater can be treated reliably.

  In this case, since the rainwater infiltration device 1 is installed below the infiltration basin 5, it can be disposed deeply in the ground and in the permeable layer 9 with groundwater.

  FIG. 3 shows a third embodiment, in which the rainwater infiltration device 1 of the present invention is disposed below the seepage reed 5 as in the second embodiment. Instead of the rainwater pipe 7 of the system, a side groove 8 was used.

  In this case, rainwater that has flowed into the side groove 8 flows into the seepage trough 5, and rainwater that cannot be treated by the seepage trough 5 and the side groove 8 flows down into the lower bag body 2, and the glass cullet 3 charged therein It penetrates into the surrounding ground through the gap. Thereby, the water permeability of the penetrating trough 5 with poor water permeability can be increased, and the water retention rate in the ground can be increased.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal front view which shows 1st Embodiment of the rainwater osmosis | permeation apparatus of this invention. It is a vertical front view which shows 2nd Embodiment of the rainwater osmosis | permeation apparatus of this invention. It is a vertical front view which shows 3rd Embodiment of the rainwater osmosis | permeation apparatus of this invention. It is a graph which shows the relationship between the thickness of the glass cullet of this rainwater infiltration apparatus of this invention, and ph adjustment ability. It is a graph which shows durability of ph adjustment ability of the glass cullet of the rainwater infiltration apparatus of this invention. It is a graph which shows the relationship between the immersion amount of the glass cullet of the rainwater infiltration apparatus of this invention, and ph change.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rainwater infiltration apparatus 2 Bag body 3 Glass cullet 4 Sandy glass cullet 5 Infiltration basin 6 Water hole 7 Rainwater pipe 8 Gutter 9 Water permeable layer

Claims (4)

  A rainwater infiltration device comprising a vertically long bag body which is disposed in a vertical hole reaching a water permeable layer drilled in the ground, made of a water permeable sheet, and filled with a crushed stone-like material.   2. The rainwater infiltration apparatus according to claim 1, wherein the crushed stone is a glass cullet or crushed stone.   The rainwater infiltration device according to claim 1 or 2, wherein the crushed stone-like material to be filled in the bag body is laid with finely pulverized material in an upper layer portion.   The rainwater infiltration device according to any one of claims 1 to 3, wherein the bag body filled with the crushed stone-like material is disposed below the infiltration basin buried in the ground.

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