JP2004293098A - Water absorptive water retentive pavement structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To lower the road surface temperature of the ground surface by rainwater. <P>SOLUTION: The rainwater stored in a rainwater storage facility 15 is supplied in a water retentive pavement layer 11 by a water supply means 17 to lower the road surface temperature of the ground surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a water-absorbent water-retentive pavement structure capable of lowering a road surface temperature.
[0002]
[Prior art]
In recent years, in order to contribute to the mitigation of the heat island phenomenon as much as possible, for example, by making a pavement surface with water retention, it retains rainwater when it rains, and vaporizes when the retained rainwater evaporates Means for lowering the road surface temperature by heat are known, and some of them are already installed on the road surface.
[0003]
[Problems to be solved by the invention]
Since the pavement surface having water retention has a limited water retention capacity for storing rainwater, if it does not rain for a few days in midsummer, it evaporates immediately and the water retention state becomes zero. For this reason, to always provide the function of lowering the temperature of the pavement to the pavement surface, water had to be supplied regularly by watering trucks, and the maintenance and management of the water was very troublesome. It is. Moreover, it was not desirable in terms of watering labor and watering cost.
[0004]
Therefore, an object of the present invention is to provide a water-absorbent water-retentive pavement structure that does not require running costs and can obtain a road surface in a water-retained state without supplying water by means such as watering. And
[0005]
[Means for Solving the Problems]
In order to achieve the above object, according to claim 1 of the present invention, a water-retentive pavement layer having a surface for retaining rainwater to a saturated state, and a water-collecting pavement provided along the water-retention pavement layer at a predetermined interval. A gutter provided with a trough,
A rainwater storage facility for storing rainwater continuously buried underground along the gutter, wherein the water-retentive pavement layer absorbs rainwater in the rainwater storage facility and transfers the rainwater into the water-retentive pavement layer. It is characterized by comprising water supply means for supplying.
[0006]
As a result, the rainwater when it rains accumulates in the rainwater storage facility. The amount of water stored at this time can be determined by calculating the average value of the amount of rainfall and the amount of evaporation during the day. Therefore, it is possible to cope with the rainwater storage facility that satisfies the required amount.
[0007]
On the other hand, the rainwater in the rainwater storage facility is supplied into the water-retentive pavement layer by the water supply means, so that the water retention state is ensured. In this case, since running water is used, no running cost is required, and labor and watering cost are not required.
[0008]
According to a second aspect of the present invention, the water supply means is a water supply sheet such as a nonwoven fabric.
[0009]
Accordingly, rainwater is sucked up by the principle of the capillary tube and supplied to the water-retentive pavement layer, so that rainwater can be supplied without increasing running costs.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings of FIGS.
[0011]
FIG. 1 is a cross-sectional view showing a part of a water-absorbent water-retentive pavement structure according to the present invention, in which a road 3 is on the right side of a side groove 1 and a sidewalk 5 is on the left side of the drawing.
[0012]
The water-absorbent water-retentive pavement structure may be on the side of the sidewalk 5 or on the side of the road 3, but here the embodiment is implemented on the side of the road 3.
[0013]
The road 3 is composed of a subgrade 7, a subgrade 9, and a water-retentive pavement layer 11 on the surface from below the drawing. Between the water-retentive pavement layer 11 and the roadbed 9, there is a barrier layer 13 through which water cannot pass, and the shape including the water-retentivity pavement layer 11 is inclined downward toward the side groove 1.
[0014]
Since the roadbed 9 and the roadbed 7 are a general pavement structure, detailed description is omitted here.
[0015]
The water-absorbent water-retentive pavement structure includes a water-retentive pavement layer 11 on the surface, a rainwater storage facility 15 for storing rainwater, and water supply means for supplying rainwater accumulated in the rainwater storage facility 15 into the water-retention pavement layer 11 on the surface. 17
[0016]
As shown in FIG. 3, the water-retentive pavement layer 11 on the surface has a shape in which a water-retentive material 21 is filled in a void formed between coarse aggregates 19 of asphalt pavement.
[0017]
The water retaining material 21 is required to have a volume that does not change or expand when water is absorbed, and to have a sufficient suction capacity and a head difference.
[0018]
As a material of the water retaining material 21, a calcium carbonate-based material having an infinite number of gaps is preferable.
[0019]
The water retention material 21 is used, for example, in the form of a cement milk melted with water together with cement or silica sand. At the time of construction, after the asphalt pavement is hardened, the water retention material 21 is turned into a cement milk state from above. The water-retentive pavement layer 11 can be obtained by pouring the material 21.
[0020]
The barrier layer 13 is made of sand and prime coat, and has a function of preventing rainwater that has fallen on the water-retentive pavement layer 11 from passing through to the roadbed 9.
[0021]
The rainwater storage facility 15 is made of a highly durable and chemical-resistant polypropylene material into a honeycomb shape, and has a rectangular honeycomb structure 23 having a strong compressive strength in the vertical and horizontal directions, and the honeycomb structure. 23 and a waterproof sheet 25 surrounding the outer periphery of the waterproof sheet 23. The rainwater storage facility 15 sequentially connects the honeycomb structures 23 formed in a predetermined length along the longitudinal direction, and continuously surrounds the outer periphery of the honeycomb structure 23 along the side groove 1 by surrounding the outer periphery with a waterproof sheet 25. Will be arranged.
[0022]
In this case, when connecting the honeycomb structures 23 to each other, it is desirable to form a weir at a predetermined interval inside by providing a weir plate 27 therebetween. Thereby, it becomes possible to store rainwater by dividing over a certain area without being affected by conditions such as a gradient. The cross-sectional area of the rainwater storage facility 15, that is, the amount of stored water, is determined by calculating the amount of rainfall of the average number of rainy days in each season and the amount of evaporation from the road surface in one day. It is to be sent.
[0023]
The water collecting basin 29 is arranged at a predetermined interval with respect to the side ditch 1, and the upper surface of the water collecting basin 29 is a rain water drinking port 31 for taking in rain water flowing along the side ditch 1. The side surface of the catchment basin 29 on the side of the road 3 is connected to the rainwater storage facility 15 via a connecting pipe 33.
[0024]
The rainwater in the rainwater storage facility 15 is supplied to the water-retentive pavement layer 11 by a water supply means 17.
[0025]
The water supply means 17 is a means that requires no running cost at the time of operation, and a water supply sheet 35 made of a nonwoven fabric is used here.
[0026]
The water supply sheet 35 has a function of sucking up water by capillary action with a nonwoven fabric, and is disposed between the honeycomb structure 23 and the waterproof sheet 25 on the connection pipe 33 side of the water collecting basin 29. The upper end portion of the water supply sheet 35 is configured to extend upward from the waterproof sheet 25 and then be folded shortly to face the open pavement layer 37 in contact with the water-retentive pavement layer 11.
[0027]
The open-grain pavement layer 37 is provided with a predetermined width between the side gutter 1 and the water-retentive pavement layer 11, and is a pavement layer having many voids through which rainwater passes.
[0028]
The water supply means 17 may be a means for supplying rainwater sucked up by a pump 39 driven by a solar cell with no running cost into the water-retentive pavement layer 11 by a nozzle 41 as shown in FIG. It is.
[0029]
According to the water-absorbent water-retentive pavement structure configured as described above, when it rains, the rainwater is absorbed by the water-retentive pavement layer 11 until it is saturated, and then through the gutter 1 and the water collecting basin 29. It is stored in the rainwater storage facility 15. As a result, it contributes to suppression of excessive discharge of rainwater flowing to the sewage more than necessary.
[0030]
The rainwater retained in the water-retentive pavement layer 11 evaporates under the direct sunlight or the influence of the outside temperature. At this time, the road surface temperature decreases due to the heat of vaporization at the time of evaporation. As a result of the experiment, a road surface temperature reduction effect of about 14 ° C. or more was obtained under conditions of clear weather and a temperature of 30 ° C.
[0031]
On the other hand, the rainwater retained in the water-retentive pavement layer 11 disappears due to evaporation. At this time, the rainwater in the rainwater storage facility 15 is sucked up by the water supply sheet 35 and supplied to the water-retention pavement layer 11. Will be done. As a result, the water-retentive pavement layer 11 does not dry out the retained rainwater, and the water-retention state is ensured. In this case, the use of rainwater and the use of the water supply sheet 35 do not require any running cost, and have advantages such as maintenance and management being performed periodically.
[0032]
【The invention's effect】
As described above, according to the first aspect of the present invention, since it becomes possible to supply rainwater stored in the water-retentive pavement layer, it is possible to reduce the road surface temperature without running costs. This is very favorable in terms of maintenance and management costs.
[0033]
Further, according to the second aspect of the present invention, since the water supply sheet is used, there is an advantage that running cost is completely unnecessary.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a part of a water-absorbent water-retentive pavement structure according to the present invention.
FIG. 2 is a schematic plan view of FIG.
FIG. 3 is an enlarged explanatory view of a part of the water-retentive pavement layer.
FIG. 4 is a schematic cross-sectional view similar to FIG. 1 showing a water supply means for supplying rainwater into a water-retentive pavement layer by a pump driven by a solar cell instead of a water supply sheet.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Gutter 3 Roadway 7 Subgrade 9 Subgrade 11 Water-retentive pavement layer 13 Blocking layer 15 Rainwater storage facility 17 Water supply means 29 Water collecting basin 35 Water supply sheet 37 Opening pavement layer

Claims (2)

A water-retentive pavement layer on the surface that retains rainwater until saturation, and a gutter provided along the water-retentivity pavement layer and provided with water collecting basins at predetermined intervals,
A rainwater storage facility for storing rainwater continuously buried underground along the gutter, wherein the water-retentive pavement layer absorbs rainwater in the rainwater storage facility and transfers the rainwater into the water-retentive pavement layer. A water-absorbent water-retentive pavement structure comprising a water supply means for supplying water. The water-absorbent water-retentive pavement structure according to claim 1, wherein the water supply means is a water supply sheet such as a nonwoven fabric.

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