JP2006249760A - Water retentive block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water retentive block capable of obtaining strength to be required and, at the same time, maintaining a water retentive function for a long period of time. <P>SOLUTION: It is so characterized that the water retentive block is constituted by covering at least the upper surface 2a and two sides 2b of a water retentive material 2 consisting of a porous substance having water retentivity with a surface material 3 having strength higher than the water retentive material 2 and permeability. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a block constituting a pavement surface such as a sidewalk or a roadway, and more particularly to a water retaining block capable of effectively mitigating a heat island phenomenon in an urban area.

Conventionally, a concrete interlocking block has been widely used as a member constituting a pavement surface in a sidewalk or a plaza.
FIG. 6 shows a pavement structure by a conventional interlocking block used in a sidewalk, a park, etc., and a layer of a sand cushion 2 is formed on the roadbed 1, and a rectangular parallelepiped shape is formed on the sand cushion 2. A large number of concrete interlocking blocks 3 are laid.

  By the way, in recent years, the heat island phenomenon in urban areas has become a major problem, and in order to solve this, the surface temperature of buildings such as rooftop greening and highly reflective paint, and the surface of paved surfaces such as roads and sidewalks Various countermeasures such as those for reducing the temperature are being developed.

  The surface temperature countermeasure on the pavement surface is mainly by providing water retention to the interlocking block 3 and evaporating the water retained in the interlocking block 3 during rain or the like by the energy of solar heat during fine weather. The temperature of the surface of the interlocking block 3, that is, the pavement surface is lowered by the heat of vaporization. By the way, water supply to the interlocking block 3 includes water retention pavement technology (passive technology) by natural water supply accompanying rainfall, and technology to actively supply water from a water supply pipe buried under the interlocking block 3 (active). Technology).

  On the other hand, as a conventional technique for imparting water retention to the interlocking block 3, there is known a technique in which the interlocking block 3 is formed by adding a water retaining agent such as a polymer to concrete.

However, in the interlocking block 3 having the conventional water retention, when the water retention performance is to be improved, the content of the water retention agent is excessively increased, and it is difficult to obtain sufficient strength. was there.
In addition, there is a limit to the sustainability of the water retention agent itself. For example, in the case of using the polymer, the water retention property cannot be maintained for a long time because it decomposes in about 2 years. There was also a problem.

  This invention is made | formed in view of this situation, and makes it a subject to provide a water retention block which can obtain desired intensity | strength and can maintain water retention performance over a long period of time.

  In order to solve the above-mentioned problem, the invention described in claim 1 is characterized in that at least the upper surface and two opposing side surfaces of a water-holding material made of a porous material having water-retaining property are stronger than the water-holding material and have water permeability. It is characterized by being covered with a surface material having properties.

Here, the said surface material needs to have the predetermined intensity | strength as a block which comprises a pavement surface, and water permeability. And about intensity | strength, it can respond | correspond by setting material strength or thickness dimension by the place used. As for the water permeability, it is preferable to have a water permeability of 1 × 10 ⁻² cm / sec or more as in the invention described in claim 2.
As such a surface material, for example, concrete can be used.

  Furthermore, in the invention according to claim 1 or 2, the water retaining material does not require a large strength, but it needs to have a predetermined water retaining property. As this water retention property, it is preferable that the water absorption is 10% or more as in the invention described in claim 3. As a material constituting such a water retention material, the water retention property can be maintained semipermanently. Pumice or brick is preferred. By the way, when using bricks, general-purpose bricks classified as 10%, 13%, or 15% in the JIS standard can be used.

  According to the water-retaining block according to any one of claims 1 to 3, the water-retaining block is configured by covering at least the upper surface and two opposite side surfaces of the water-retaining material made of a porous material having water retentivity with a surface material having water permeability. For this reason, water that has permeated from the surface material during rainfall is retained in the internal water retention material. And when a surface material is heated by sunlight at the time of fine weather, the water in the said water retention material evaporates from a surface material, and a temperature rise is suppressed by cooling a surface material by the heat of vaporization in that case.

  As a result, by spreading the water retaining blocks over a wide area, it is possible to greatly relieve the strong reflection in summer and the heat island phenomenon that is a problem particularly in urban areas.

Moreover, since the said surface material is formed in the gate type | mold by the at least upper surface and two opposing side surfaces, the load which acts on the said surface material can be supported stably.
In addition, even when the water retaining material becomes full during rain and the water retaining effect is saturated, rain water can be directly released to the soil from the side surface of the surface material having water permeability.

1 to 5 show an embodiment of a water retention block according to the present invention and a pavement structure using the same.
First, the water retention block 1 shown in FIG. 1 and FIG. 3 is obtained by integrating a rectangular parallelepiped brick (water retention material) 2 that is a porous material with a surface material 3 from its upper surface 2a and 4 side surfaces 2b. .

Moreover, the water retaining block 5 shown in FIGS. 2 and 3 is obtained by covering the upper surface 6 a and the two side surfaces 6 b of the same brick 6 with the surface material 7 and integrating them.
Here, the surface materials 3 and 7 are both made of concrete having a water permeability of 1 × 10 ⁻² cm / sec or more. Moreover, the thickness dimension, concrete strength, etc. are set so that these surface materials 3 and 7 may have the intensity | strength corresponding to the place or use, such as a sidewalk, a square, a roadway, a parking lot, for example.

  On the other hand, as the bricks 2 and 6, general-purpose bricks classified as 10%, 13%, or 15% in the JIS standard are used.

Here, the specific dimensions of the brick 2 and the surface material 3 when the water retaining block 1 having the shape shown in FIG. 1 is formed in a normal outer dimension (length 21 cm × width 10 cm) in accordance with JIS R1250. Is as follows.
First, assuming that the total amount of solar radiation is about 20 MJ / m ² days and the maximum evaporation temperature is about 5 kg / m ² days when the maximum temperature is 30 ° C. or more, the maximum evaporation amount on the surface of the water retaining block 1 is About 0.1 kg / day.

Therefore, when a brick 2 having a density of 1800 kg / m ³ and a water absorption rate of 10% (4 types) is used, the required volume is 0.000583 m ³ .
On the other hand, if the thickness dimension of the upper surface and the side surface of the surface material 3 is 2 cm, the planar dimension of the brick 2 is 0.170 m × 0.060 m. Therefore, the required height dimension in the brick 2 is 0.057 m.

  From the above, as the water retaining block 1, the upper surface 2a and the four side surfaces 2b of the brick 2 having a length of 17 cm, a width of 6 cm, and a height of 6 cm can be covered and integrated with the surface material 3 to satisfy the above condition.

  In addition, referring to the thickness dimension of a general interlocking block, according to “Interlocking Block Pavement Design and Construction Guidelines (Roadway) Revised Edition, May 1994, Interlocking Block Pavement Technology Association” (1) 6cm for sidewalks, parks and open spaces, and (2) 8cm for roadways and parking lots, it is possible to use the water retaining block 1 as an alternative to the interlocking block. is there.

According to the water retaining blocks 1 and 5 having the above configuration, the top surfaces 2a and 6a and the four side surfaces 2b or the two side surfaces 6b of the bricks 2 and 6 having a water absorption rate of 10% or more are 1 × 10 ⁻² cm / sec or more. As shown in FIG. 4 (b), the water permeated from the surface material 1 is retained by the internal bricks 2 and 6 because it is integrated with the surface materials 3 and 7 made of concrete having the water permeability. Water is retained in the material.

Then, as shown in FIG. 4 (a), when the surface materials 3, 7 are heated by sunlight in fine weather, the water stored in the bricks 2, 6 evaporates from the surface materials 3, 7, The surface materials 3 and 7 are cooled by the heat of vaporization.
Therefore, by spreading these water retaining blocks 1 and 5 over a wide area, it is possible to greatly relieve the strong reflection in summer and the heat island phenomenon which is a problem particularly in urban areas.

Further, since the surface material 3 has four side surfaces and the surface material 7 has two opposite side surfaces and is formed in a gate shape, the load acting on the surface materials 3 and 7 is stably supported. be able to.
Moreover, even when the bricks 2 and 6 are full and the water retention effect is saturated at the time of rain, the rainwater can be directly released to the soil 10 from the side surfaces of the surface materials 3 and 7 as shown in FIG. .

  In addition, in the said embodiment, although demonstrated about the case where the water retention blocks 1 and 5 were applied to the water retention pavement technique (passive technique) by the natural water supply accompanying rainfall, it is not restricted to this, For example, FIG. As shown in FIG. 5, a technique (active technique) in which a water absorption pipe 11 is embedded in the soil 10 below the water retaining blocks 1 and 5 and water is actively supplied from the water supply pipe 11 to the brick via the soil 10. It is possible to apply to the same.

  In the pavement structure using the water retaining blocks 1 and 5, the soil 10 is water-retaining soil or hydrophilic soil mixed with water-retaining materials such as finely pulverized unglazed bricks. It is preferable to do. By using such soil 10, water retention from the soil 10 to the water retention blocks 1 and 5 can be performed smoothly, and even when the water supply pipe 11 is provided, the number of installation locations can be reduced. become.

It is a perspective view which shows one Embodiment of the water retention block of this invention. It is a perspective view which shows the modification of FIG. It is sectional drawing in the center part of FIG. 1 and FIG. It is sectional drawing for demonstrating the effect | action of the water retention block of FIG. 3, (a) is the state of the evaporation at the time of fine weather, (b) is a figure which shows the state of the water retention at the time of rain. It is a longitudinal cross-sectional view which shows the pavement structure which applied the water retention block of FIG. 1 or FIG. 2 to the active technique. It is sectional drawing which shows the pavement structure by the conventional interlocking block.

Explanation of symbols

1, 5 Water retention block 2, 6 Brick (water retention material)
2a, 6a Upper surface 2b, 6b Side surface 3, 7 Surface material

Claims (3)

  A water retention block characterized by covering at least the upper surface and two opposite side surfaces of a water retention material made of a porous material having water retention property with a surface material having a strength higher than that of the water retention material and having water permeability. The water retaining block according to claim 1, wherein the surface material has a water permeability of 1 × 10 ⁻² cm / sec or more.   The water retention block according to claim 1 or 2, wherein the water retention material is pumice or brick having water retention of 10% or more.

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