JP2006161335A - Block for paving - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a block for paving having high water retainability and temperature reduction effect by heat of vaporization and its sustainment performance. <P>SOLUTION: This block 11 for paving is formed by covering the surface of a rectangular parallelepiped block body 12 with a porous layer 13. The block body 12 is formed by uniformly mixing a wood powder of 1 mm or less in grain size, a sand of 2 mm or less in grain size, and a binder such as cement with each other and hardening the mixed material. The porous layer 13 is formed by fixing an inorganic particles such as sand, pebbles, and ceramic particles to the surface of the block body 12 with an adhesive agent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paving block (interlocking block) for paving by paving on a road surface.

  It is well known that cities are hotter than suburbs. The temperature difference between the city and the suburbs is observed throughout the year, but it is said that the temperature difference is particularly large at night without wind. Such a phenomenon that the temperature in the urban area is locally higher than in the suburbs or around the urban area is called a heat island phenomenon.

  The cause of the heat island phenomenon has been pointed out as a decrease in the area of green space in urban areas, but pavement using highly water-tight materials such as asphalt pavement on roads (also called water-tight pavement). It is one. In watertight pavement, the ground is covered with a highly watertight material, so that water does not penetrate under the roadbed and water does not evaporate from the ground. For this reason, the water spray effect cannot be expected, and the road is dried and the surface temperature is likely to rise. In watertight pavement, the solar heat during the day increases the temperature to the depth below the roadbed, and the accumulated heat is released at night. Therefore, the temperature in urban areas, especially the nighttime temperature, has been increasing year by year, and countermeasures against the heat island phenomenon are urgently needed.

  As measures to alleviate the heat island phenomenon, expansion of green spaces and permeable pavements in cities have been proposed. However, although it is an expansion of green space, it is not easy to implement in limited urban land areas.

  The water-permeable pavement is obtained by covering the ground with a roadbed made of a porous material. As a paving block for performing water-permeable paving, there is a porous block in which pebbles and ceramic particles are hardened. Since the water-permeable pavement allows water to pass therethrough, water such as rain permeates through the water-permeable pavement and permeates the ground below the roadbed. When the temperature on the ground rises, the water that has permeated the ground evaporates through the water-permeable pavement and relieves the rise in temperature by taking away the heat of vaporization.

  Regarding water-permeable pavement, a short-term temperature reduction effect has been recognized in recent studies. However, in the case of water-permeable pavement, rainwater and the like easily pass through the ground, while water that has penetrated the ground quickly evaporates through the water-permeable pavement and diverges into the air. The ground under the roadbed dries quickly. Therefore, in the case of water-permeable pavement, even if a short-term temperature reduction effect was recognized, the temperature reduction effect could not be sustained. One report states that in the case of permeable pavement, the surface will be the same as that of general pavement in a few hours after rainfall.

  Thus, in water-permeable pavement, water cannot be held, and therefore the effect of reducing the temperature is not maintained, and a pavement material having high water retention is required.

  The present invention has been made in view of the technical problems as described above, and the object thereof is to provide a paving block having high water retention performance, high temperature reduction effect due to vaporization heat, and high sustainability. It is in.

  The paving block of the present invention is characterized in that wood powder and sand are mixed and hardened with a binder. The wood powder material may be wood chips or sawdust from wood, granulated or powdered bamboo or grass, or recycled wooden construction waste. . As sand, mountain sand or pure sand is desirable. Cement is used as the main component of the binder, but it may contain a hard adhesive such as an epoxy resin adhesive.

  The paving block of the present invention is laid down on the ground to constitute a roadbed. Since this paving block contains wood powder, when it gets wet by rain or water spray, the wood powder can contain water and retain water. Therefore, the paving block itself has high water retention.

  Moreover, according to this paving block, the paving block is made porous by adding wood powder and sand as aggregates, and has an appropriate water permeability. Therefore, when wet by rain or water spray, the water permeates through the paving block and permeates the ground below the roadbed. In addition, since the surface under the roadbed that is wet and contains water is covered with a paving block containing a large amount of water, it becomes difficult to dry and the water retention of the ground itself can be improved.

  Therefore, a large amount of water can be held on the pavement block or the ground by rain or water spray on the road surface on which this pavement block is laid, and when the temperature rises, the moisture retained in the pavement block Can evaporate and take heat of vaporization and lower the temperature. Moreover, since the paving block has high water retention performance and can also increase the water retention performance of the ground, the water retention performance can be maintained for a long time. Therefore, the effect of lowering the temperature also lasts for a long time.

  The wood powder used in the paving block of the present invention preferably has a particle size of 1 mm or less, and the sand has a particle size of 2 mm or less. This is because when the particle size of the wood powder is larger than 1 mm, the wood powder hardly absorbs water and the water retention of the paving block is lowered. Moreover, when the particle size of sand becomes larger than 2 mm, the clearance (pores) in the paving block becomes large and water easily passes through, and the water retention of the paving block decreases. Further, when the particle size of the wood powder is large, the strength of the paving block is lowered, and it is not suitable for use for paving.

  In the paving block of the present invention, it is desirable that the mixing ratio of the wood powder is 25 to 75% of the capacity of the aggregate containing sand and wood powder. This is because when the mixing ratio of the wood powder is 25% or less, the water retention of the paving block is lowered. Moreover, it is because the intensity | strength of a paving block will fall that the mixing ratio of a wood flour is 75% or more.

  In the paving block of the present invention, the surface may be covered with a porous layer obtained by solidifying inorganic particles such as sand, pebbles and ceramic particles. By covering the surface with an inorganic porous layer, the strength of the surface of the paving block can be increased, and the durability of the paving block can be improved.

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

  FIG. 1 is a perspective view showing a paving block 11 according to an embodiment of the present invention. The paving block 11 includes a block body 12 and a porous layer 13 on the surface. The pavement block 11 is formed to have an appropriate thickness in consideration of strength, for example, about 5 to 6 cm, and is formed into a planar shape that can be laid on the road surface with almost no gap, for example, a square, a rectangle, or a hexagon. Has been. However, if the paving blocks 11 are spread exactly without any gaps, there is a risk that water may accumulate when there is a lot of rainfall. Therefore, convex portions 14 are provided asymmetrically on both side surfaces and both end surfaces of the block main body 12 so that a gap is formed between the paving blocks 11.

  The block main body 12 includes wood powder obtained by pulverizing wood (for example, thinned wood or building waste), bamboo, grass, or the like, and sand such as mountain sand or pure sand soil. These are mixed almost uniformly in a binder, solidified with a binder while applying pressure, and molded. A plurality of types of wood flour may be used, but those having a particle size of 1 mm or less are preferable in order to improve water absorbability and water retention. In order to make the block main body 12 porous and have appropriate water permeability, the sand preferably has a particle size of 2 mm or less. Furthermore, wood powder and sand are dispersed in the binder as uniformly as possible.

  The mixing ratio of wood powder and sand is preferably 25 to 75% with the capacity of aggregate such as wood powder and sand (coal ash etc. may be added) being 100%, especially in the aggregate It is desirable that the mixing ratio of wood flour is about 50%. It is because the water retention of the block 11 for pavement falls that the mixing ratio of wood powder is 25% or less. In addition, since the block body 12 is given strength by sand, the mechanical strength of the paving block 11 is lowered when the mixing ratio of the wood flour is 75% or more.

  Further, in order to give the block body 12 water permeability, a part of the pores or gaps needs to appear on the surface of the block body 12. In order to increase water absorption, it is desirable that a part of the wood flour is exposed on the surface of the block body 12. Furthermore, since the internal wood powder must also absorb water, the porosity due to the pores or gaps inside the block body 12 must be such that water can be smoothly guided to the internal wood powder. Rather, the internal pores need to be connected to each other. That is, the block body 12 is an open-celled porous body having an appropriate gap inside.

  The binder is mainly composed of cement, but may contain a hard adhesive such as an epoxy resin adhesive. In addition, the binder may contain a curing agent or a reinforcing agent.

  The porous layer 13 is obtained by solidifying inorganic particles such as pebbles, sand, and ceramic particles having a relatively large particle size with a hard adhesive such as an epoxy adhesive, and the surface is leveled. If the block main body 12 is exposed on the surface, there is a possibility that abrasion due to friction with the shoe sole may become severe. Therefore, by covering the surface with a porous layer 13 formed of a material with high wear resistance, it is possible to use for paving. The surface strength of the block 11 is increased to prevent the wear of the paving block 11 and to improve durability. However, the amount of hard adhesive should be an appropriate amount of hard adhesive so that the gaps between the particles are not filled and water cannot pass through, and the particles can be firmly bonded so that the particles do not peel off. There is a need.

  FIG. 2 is a process diagram for explaining the manufacturing process of the paving block 11. In manufacturing the paving block 11, as shown in FIG. 2, each wood powder of a predetermined particle size, which is a raw material of the block body 12, sand of a predetermined particle size, and each binder material are weighed (step S1), This is stirred and kneaded uniformly (step S2). On the other hand, inorganic particles such as sand, pebbles, and ceramic particles, which are raw materials of the porous layer 13, and an adhesive such as an epoxy resin are weighed (S3), and these are stirred and kneaded uniformly (step S4). ).

  Next, the kneaded raw material of the block body 12 is poured into the mold of the vibration press machine so as to have a predetermined thickness, and the raw material of the porous layer 13 is poured into a relatively thin layer on the raw material of the block body 12 and laminated. To do. When the raw materials have been put into the mold in this way, they are pressed from above with a pressing plate while being vibrated by a vibration press machine and molded into a predetermined shape (step S5).

  When the pavement block 11 is thus molded, the pavement block 11 is taken out of the mold while remaining uncured (step S6). Next, the surface of the paving block 11 is washed out to expose the internal wood powder on the surface of the paving block 11 (step S7). When the washing is completed, it is left as it is, and the binder is cured and cured (step S7). When the binder is hardened and the paving block 11 is completed, product inspection is performed visually or by a measuring instrument (step S8). Products that are determined to be defective as a result of product inspection are discarded. In addition, the product determined to be good in the product inspection is wrapped in a curing sheet or the like, or packed as it is in a cardboard box (step S9) and shipped (step S10).

  The paving block 11 of the present invention is laid down on the ground to form a roadbed. Since the pavement block 11 contains wood powder, the wood powder contains water and exhibits high water retention when wet by rain or water spray. Further, according to the paving block 11, the paving block is made porous with wood powder and sand and has an appropriate water permeability, so that when it gets wet by rain or water spray, It penetrates and penetrates the ground under the roadbed. In addition, since the ground under the roadbed that is wet and contains water is covered with the paving block 11 that contains a large amount of water, the ground is difficult to dry and the water retention of the ground itself is improved.

  Therefore, on the road surface on which the paving block 11 is laid, a large amount of water can be held on the paving block or the ground by rain or water spray, and when the temperature rises, it is held in the paving block. Moisture evaporates and takes heat of vaporization, and can lower the temperature. Moreover, since the paving block has high water retention performance and can also increase the water retention capacity of the ground, a large amount of water can be maintained for a long time. Therefore, the effect of gradually evaporating water and lowering the temperature can be maintained for a long time, and the effect is high in mitigating the heat island phenomenon.

  In addition, since most of the raw material of this paving block 11 is made of natural raw materials such as wood powder, sand, cement, etc., it is decomposed naturally by pulverizing and embedding in the ground at the time of disposal. do not need.

  Next, an actual measurement example will be described. FIG. 3 is a table showing the mixing ratio (weight ratio) of the block body 12 and the porous layer 13 constituting the paving block 11 of the present invention. What is represented as CZ250 in this table is Mighty 150 manufactured by Kao Corporation, and A2-1 is relatively large pebbles and sand produced in Dalian, China. W / C is the weight ratio of water to cement. Moreover, since the ratio of the density of wood powder, mountain sand, and gravel is 1:10, the mountain sand, gravel, and wood powder are 100%, and the mixing ratio of wood powder in volume is 43%. . Further, according to such a paving block 11, a water retention rate of about 50% was obtained.

  4 and 5 show a comparison of effects with other paving blocks using this paving block. That is, FIG. 4 shows temporal changes in the water retention amount (represented by the weight of the retained water) of the paving block, upper sandstone, cement brick, burned brick, interlocking collection, and red brick of the present invention. It is a figure which shows the measurement result. FIG. 5 is a diagram showing the results of measuring temporal changes in the surface temperature of the paving block, upper sandstone, cement brick, burned brick, interlocking collection, and red brick of the present invention. Here, the interlocking collection is a block in which cement is mixed in red brick.

  As can be seen from FIG. 4 and FIG. 5, according to the paving block of the present invention, it can be seen that the duration of the water retention performance is longer than that of the other paving blocks, and the rising speed of the surface temperature is slow. Therefore, the use of the paving block of the present invention on an urban road or the like can suppress an increase in temperature, which is highly effective in mitigating the heat island phenomenon.

  Further, although details are omitted, a sample of the present invention in which the mixing ratio of the wood powder is 50% (volume) in the aggregate was prepared and various measurements were performed. First, when a bending test was performed on the sample of the present invention, a value of 3.8 MPa was obtained. Since the bending strength required for the paving block (interlocking block) is 3.0 MPa, sufficient bending strength is achieved in the sample of the present invention. Next, when the water retention amount was measured for the sample of the present invention whose width, length, and height sizes were 100 mm, 200 mm, and 60 mm, respectively, it was 500 cc. About the comparative example which does not contain wood flour, since the water retention amount is 150-250 cc, it turns out that a big water retention amount is obtained. Further, when the weight of the sample of the present invention was measured, it was 2/3 of the weight of the comparative example not containing wood flour when dried, and 4/5 of the comparative example when saturated with water absorption. It was. It turns out that it is excellent also in water retention from now on.

1 is a perspective view of a paving block according to an embodiment of the present invention. It is process drawing which shows the manufacturing process of the block for paving of this invention. It is a table | surface which shows an example of the component of the block for paving of this invention. It is a figure which compares and shows the temporal change of the amount of water retention of the paving block of this invention, and the other paving block. It is a figure which compares and shows the time change of the surface temperature of the paving block of this invention, and the other paving block.

Explanation of symbols

11 Blocks for paving 12 Block body 13 Porous layer

Claims (7)

  Pavement block characterized by mixing wood powder and sand and solidifying with a binder.   2. The paving block according to claim 1, wherein the particle size of the wood powder is 1 mm or less and the particle size of the sand is 2 mm or less.   3. The paving block according to claim 1, wherein the mixing ratio of the wood powder is 25 to 75% of the capacity of the aggregate containing sand and wood powder.   The paving block according to claim 1, 2 or 3, wherein the raw material of the wood powder includes at least one of wood, bamboo, grass, and wooden construction waste.   The paving block according to claim 1, wherein the sand is mountain sand or pure sand.   The paving block according to claim 1, wherein a main component of the binder is cement.   The paving block according to claim 1, wherein the surface is covered with a porous layer obtained by solidifying inorganic particles such as sand, pebbles and ceramic particles.

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