Pavement Structure

Abstract

To provide a pavement structure having countermeasures against heat by keeping a road surface in a wet state.SOLUTION: A pavement structure has, at least, a wet surface layer 3 forming a road surface and having pumping property and water permeability, a capillary water holding layer 32 provided under the wet surface layer, having the pumping property and water permeability and capable of holding capillary water, a pumping member 7 provided inside the capillary water holding layer and capable of supplying moisture to the wet surface layer by a capillary phenomenon, and an impervious member 42 provided on a bottom face and / or side faces of the capillary water holding layer. In a rainfall, rain water is led to the capillary water holding layer and held therein. In a fine weather, the capillary water can be supplied to the wet surface layer by the capillary water holding layer and the pumping member, by the capillary phenomenon. The pumping member has a larger pumping speed than the capillary water holding layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pavement structure that can keep the road surface moist and provide protection against heat. [Background technology]

[0002] Conventionally, there is a type of wet pavement in which the pores of porous asphalt pavement are filled with fine granular material, and the capillary action of water supplied to the underside of the pavement keeps the road surface moist, suppressing the rise in road surface temperature as the water evaporates. There is also a type of permeable pavement in which rainwater permeates into the roadbed and subgrade during rainfall through the pores of the porous asphalt pavement. These types of pavement have different structures and functions.

[0003] Several inventions have been disclosed that attempt to composite wet pavement and permeable pavement, which have different pavement structures and functions as described above. For example, Patent Document 1 discloses an invention in which, as shown in Figure 1 of the document, one side is a permeable pavement made of open-graded asphalt, and the other side is a water-retentive pavement in which the voids in the open-graded asphalt are filled with water-retentive cement milk, with the underlying structure being a common base layer containing soil cement, with water-retentive pillars in the layer below that, and a water-impermeable layer in the lowest layer.

[0004] Furthermore, Patent Document 2 discloses an invention in which, as shown in Figure 1 of the document, a water-retentive region and a water-permeable region are formed in the surface layer, a water-retentive diffusion layer is formed below the surface layer, and a roadbed is formed below that. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-166207 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-207433 Summary of the Invention [Problem to be solved by the invention]

[0006] However, while the conventional pavement structure described above has both a water-retaining area and a water-permeable area in the surface layer, it is not able to quickly allow rainwater to penetrate below the surface layer during rainfall, and quickly pump up the water held below the surface layer during fine weather. Furthermore, the amount of rainwater stored is far from sufficient, which creates the problem of not being able to continuously achieve the heat mitigation effect of wet pavement.

[0007] In view of the various problems with the prior art described above, the present invention aims to provide a pavement structure that can keep the road surface moist and provide protection against heat. [Means for solving the problem]

[0008] The invention related to (1) is a pavement structure comprising at least a wet surface layer that forms a road surface and has water pumping and permeability, a capillary water retention layer that is provided below the wet surface layer and has water pumping and permeability and can retain capillary water, a pumping member that is provided inside the capillary water retention layer and can supply water to the wet surface layer by capillary action, and a water-blocking member that is provided on the bottom and / or side of the capillary water retention layer, wherein during rainfall, rainwater penetrates and is retained in the capillary water retention layer through the wet surface layer, and during fine weather, capillary water can be supplied to the wet surface layer by the capillary water retention layer and the pumping member, and the pumping member has a higher pumping speed than the capillary water retention layer.

[0009] According to the invention related to (1) above, when it rains, rainwater penetrates and is retained in the capillary water retention layer through the wet surface layer, and when it is sunny, capillary action allows the capillary water retention layer and the pumping member to supply capillary water to the wet surface layer. This makes it possible to continuously obtain the cooling effect of the wet pavement even on sunny days by utilizing the rainwater retained in the capillary water retention layer. Furthermore, by installing a pumping member inside the capillary water retention layer that has a higher pumping speed than the capillary water retention layer, it is possible to quickly supply water to the wet surface layer, thereby promoting the pumping effect of the capillary water retention layer itself.

[0010] The invention related to (2) is a pavement structure described in (1) above, in which the pumping member consists of a hollow portion extending in an approximately vertical direction and a pumping wall formed around the hollow portion and capable of pumping water by capillary action.

[0011] According to the invention related to (2) above, a pumping member consisting of a hollow portion extending substantially vertically and a pumping wall formed around the hollow portion that can pump water by capillary action is provided inside the capillary water retention layer. This allows rainwater to quickly penetrate into the capillary water retention layer through the hollow portion during rainfall and be retained therein. On the other hand, on sunny days, the pumping wall on the hollow portion side dries, allowing rainwater remaining below the hollow portion and moisture retained in the capillary water retention layer to be quickly pumped up. In addition, the pumping wall of the pumping member has a higher pumping rate than the capillary water retention layer, allowing moisture to be quickly supplied to the wet surface layer, thereby enhancing the pumping effect of the capillary water retention layer itself.

[0012] The invention related to (3) is a pavement structure described in (1) or (2) above, in which a reservoir layer having a higher water retention rate than the capillary water retention layer is provided below the capillary water retention layer, and the pumping member is extended into the reservoir layer.

[0013] According to the invention related to (3) above, a reservoir layer having a higher water retention rate than the capillary water retention layer is provided below the capillary water retention layer, and the pumping member is extended to the inside of the reservoir layer, so that more rainwater can be stored in the reservoir layer and the pumping member can quickly and continuously supply moisture to the wet surface layer.

[0014] The invention related to (4) is a pavement structure described in (1) or (2) above, which has a connection part connected to the capillary water retention layer, and the capillary water retention layer is capable of conducting moisture from the outside through the connection part.

[0015] The invention related to (5) is a pavement structure described in (3) above, which has a connection part connected to the reservoir layer, and the reservoir layer is capable of conducting water from the outside through the connection part.

[0016] According to the inventions (4) and (5) above, the structure is such that water can be guided from the outside to the capillary water retention layer or reservoir layer provided below the wet surface layer through the connection part, so that it is possible to stably supply water for a longer period of time even on sunny days, and it is possible to continuously obtain the cooling effect of the wet pavement. [Brief explanation of the drawings]

[0017] [Figure 1] 1A and 1B are cross-sectional views showing a first embodiment of a pavement structure of the present invention, in which (a) is a cross-sectional view showing each component, and (b) is a cross-sectional view showing the state during rainfall. [Figure 2] 1A and 1B are cross-sectional views showing a first embodiment of the pavement structure of the present invention, with FIG. 1C showing the state on a fine day. [Figure 3] 1A and 1B are cross-sectional views showing a second embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each component, and (b) is a cross-sectional view showing the state during rainfall. [Figure 4] 10A and 10B are cross-sectional views showing a second embodiment of the pavement structure of the present invention, with FIG. 10C showing the state on a fine day. [Figure 5]10A and 10B are cross-sectional views showing a third embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each component, and (b) is a cross-sectional view showing the state during rainfall. [Figure 6] 10A and 10B are cross-sectional views showing a third embodiment of the pavement structure of the present invention, with FIG. 10C showing the state on a fine day. [Figure 7] 5A to 5C are schematic cross-sectional views illustrating the state of the third embodiment of the pavement structure of the present invention in stages during rainfall. [Figure 8] 5A to 5C are schematic cross-sectional views illustrating the third embodiment of the pavement structure of the present invention in stages on a sunny day. [Figure 9] 4A and 4B are cross-sectional views showing a fourth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 10] 5A and 5B are cross-sectional views showing the fifth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 11] A cross-sectional view showing the sixth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 12] 7A and 7B are cross-sectional views showing the seventh embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 13] 10A and 10B are cross-sectional views showing the eighth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 14] A cross-sectional view showing the 9th embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing each configuration, (b) is a cross-sectional view showing the appearance during rainfall, and (c) is a cross-sectional view showing the appearance during sunny weather. [Figure 15]10A and 10B are cross-sectional views showing a tenth embodiment of the pavement structure of the present invention, where (a) is a horizontal cross-sectional view showing each component, and (b) is a horizontal cross-sectional view. [Figure 16] FIG. 14 is a cross-sectional view showing an eleventh embodiment of the pavement structure of the present invention. [Figure 17] 12A and 12B are cross-sectional views showing a twelfth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing the state during rainfall, and (b) is a cross-sectional view showing the state during fine weather. [Figure 18] 13A and 13B are cross-sectional views showing a thirteenth embodiment of the pavement structure of the present invention, where (a) is a cross-sectional view showing the state during rainfall, and (b) is a cross-sectional view showing the state during fine weather. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, each embodiment of the pavement structure of the present invention will be described with reference to the drawings.

[0019] (First embodiment) As standard cross-sectional views showing the first embodiment of the pavement structure of the present invention, Figure 1(a) shows a cross-sectional view showing each component of the pavement structure 1, Figure 1(b) shows a cross-sectional view showing the appearance during rainfall, and Figure 2(c) shows a cross-sectional view showing the appearance during sunny weather.

[0020] In more detail, the pavement structure 1 in the first embodiment comprises a wet surface layer 3 that forms the road surface and has water pumping and permeability, a capillary water retention layer 32 that is provided below the wet surface layer 3 and is capable of retaining capillary water, and a water pumping member 7 that is provided in a substantially vertical direction in the capillary water retention layer 32 and is capable of supplying water to the wet surface layer 3 by capillary action, and further, a waterproof sheet 42 is provided on the bottom and sides of the capillary water retention layer 32 as a waterproof member.

[0021] During rainfall, as shown in Figure 1(b), rainwater penetrates and is retained in the capillary water retention layer 32 through the wet surface layer 3, and during fine weather, as shown in Figure 2(c), capillary action allows the capillary water retained by the capillary water retention layer 32 and the pumping member 7 to be supplied to the wet surface layer 3.

[0022] Well-known water-retentive pavement or water-pumping pavement can be used as the wet surface layer 3, but it is essential that it has water-pumping and water-permeability. In other words, a pavement material that can pump water from the underside of the wet surface layer 3 on fine days and allow rainwater to permeate and infiltrate below the wet surface layer 3 during rainfall is preferably used.

[0023] It should be noted that water-retentive pavements, such as those containing a large amount of water-retentive material or open-graded asphalt pavements filled with cement milk to which water-retentive material has been added, have very low permeability. Therefore, when using such water-retentive pavements as the wet surface layer 3, it is possible to form continuous voids in parts or to drill through-holes. Furthermore, there are no particular limitations on the base material for the wet surface layer 3; paving blocks, porous asphalt, porous concrete, etc. can be used as appropriate.

[0024] Furthermore, sand or sandbags with water pumping and permeability can be used as the capillary water retention layer 32, which can retain water that has infiltrated the wet surface layer 3 and transport the retained water upward by capillary action, thereby supplying water to the wet surface layer 3. With this configuration, the capillary water retention layer 32 can function as a supporting roadbed for the wet surface layer 3, while also infiltrating and retaining rainwater during rainfall and pumping up the retained water to supply it to the wet surface layer 3 during fine weather. The capillary water retention layer 32 is not limited to sand, and any fine-grained material with water pumping and permeability, such as one with a similar particle size distribution, can be used as appropriate.

[0025] Furthermore, a waterproof sheet 42 is installed on the bottom and side surfaces of the capillary water retention layer 32 as a waterproof member, preventing the water retained in the capillary water retention layer 32 from permeating or flowing out to areas other than the capillary water retention layer 32, such as the roadbed. The waterproof sheet 42 may be installed on either the bottom surface or the side surface of the capillary water retention layer 32.

[0026] The pumping member 7 in this embodiment is installed in a substantially vertical direction inside the capillary water retention layer 32 and is a member capable of pumping water upward by capillary action. In the first embodiment, a water-conducting sheet with particularly excellent pumping performance can be used, making it possible to quickly pump water that has penetrated and been retained in the capillary water retention layer 32 upward to the wet surface layer 3. Furthermore, since the pumping member 7 has a higher pumping speed than the capillary water retention layer 32, it is possible to quickly supply water to the wet surface layer 3 and also obtain the effect of promoting water pumping by the capillary water retention layer 32 itself.

[0027] (Second embodiment) As cross-sectional views showing the second embodiment of the pavement structure of the present invention, Fig. 3(a) shows the components of the pavement structure 1, Fig. 3(b) shows the configuration during rainfall, and Fig. 4(c) shows the configuration during fine weather. In the following, the components common to the first embodiment will be omitted.

[0028] The pumping member 7 in the second embodiment is a member comprising a hollow portion 71 extending in a substantially vertical direction and a pumping wall 72 formed around the hollow portion 71 and capable of pumping water by capillary action. The pumping member 7 in this embodiment is made of ceramic, and the pumping wall 72 has fine continuous voids formed therein, which enable water to be rapidly pumped upward by capillary action. The shape of the pumping member 7 is not particularly limited, and it can be cylindrical or prismatic. In addition, the pumping member 7 is not limited to being made of ceramic, and the pumping wall 72 can also be a fiber tube made of a fiber material that enables water to be rapidly pumped upward by capillary action.

[0029] 3(b), during rainfall, rainwater that has permeated the wet surface layer 3 not only directly penetrates and is retained in the capillary water retention layer 32, but also can quickly penetrate and be retained below the capillary water retention layer 32 via the hollow portion 71 of the water pumping member 7. It is preferable to provide a water-permeable screen or filter at least at the upper end of the hollow portion 71 to prevent components of the capillary water retention layer 32 or foreign matter from entering the hollow portion 71 of the water pumping member 7.

[0030] Also, the hollow portion 71 may be filled with single-grain crushed stone or the like to the extent that it does not impede water flow. In addition, in the illustrated embodiment, the upper end of the pumping member 7 is spaced apart from the underside of the wet surface layer 3 to prevent direct traffic load from being applied to the pumping member 7, but depending on the physical properties of the wet surface layer 3 and the pumping member 7, it is also possible to arrange the pumping member 7 so that the upper end of the pumping member 7 abuts against the underside of the wet surface layer 3.

[0031] On a fine day, as shown in Figure 4(c), capillary action allows the capillary water retention layer 32 and the pumping member 7 to supply capillary water to the wet surface layer 3. In particular, the hollow portion 71 of the pumping member 7 allows water to be quickly and efficiently pumped from below the capillary water retention layer 32. In addition, the pumping wall 72 of the pumping member 7 has a higher pumping speed than the capillary water retention layer 32, allowing water to be quickly supplied to the wet surface layer 3, thereby enhancing the pumping effect of the capillary water retention layer 32 itself.

[0032] (Third embodiment) As cross-sectional views showing the third embodiment of the pavement structure of the present invention, Fig. 5(a) shows a cross-sectional view of each component of the pavement structure 1, Fig. 5(b) shows a cross-sectional view showing the state during rainfall, and Fig. 6(c) shows a cross-sectional view showing the state during fine weather. In the following, the components common to the first and second embodiments will be omitted from the explanation.

[0033] 5(a), in the third embodiment, a water conducting layer 31 having a higher water pumping rate than the capillary water retention layer 32 is provided between the water pumping member 7 and the wet surface layer 3, and further, a reservoir layer 33 capable of storing water such as rainwater is provided below the capillary water retention layer 32. The water conducting layer 31 can be made of a material with continuous pores such as sand, or a water conducting sheet, which makes it possible to quickly guide the water pumped by the water pumping member 7 and the capillary water retention layer 32 in both vertical and horizontal directions.

[0034] The reservoir layer 33 can be a layer made of single-grain crushed stone or the like, and has a higher water retention rate than the capillary water retention layer 32. The pumping members 7 are provided so as to extend into the reservoir layer 33. With this configuration, as shown in Figure 6(c), it is possible to store more rainwater in the reservoir layer 33, and also to use the pumping members 7 to quickly and continuously supply moisture to the wet surface layer 3.

[0035] 7 and 8 show the stepwise movement of water through the pumping member 7 in the second and third embodiments described above. That is, as shown in Fig. 7, rainwater that has permeated the wetted surface layer 3 due to rainfall directly penetrates and is retained in the capillary water retention layer 32, and the hollow portion 71 of the pumping member 7 is temporarily filled with rainwater, allowing it to quickly penetrate and be retained below the capillary water retention layer 32. Then, over time, the rainwater leaves the pumping member 7 and is retained below the reservoir layer 33 and the capillary water retention layer 32. This makes it possible to quickly retain rainwater in the capillary water retention layer 32 and the reservoir layer 33 during rainfall.

[0036] 8, on a fine day, the pumping wall 72 on the hollow portion 71 side dries, and the water retained in the reservoir layer 33 and the capillary water retention layer 32 is pumped up by capillary action. The pumping wall 72 of the pumping member 7 has a higher pumping speed than the capillary water retention layer 32, and therefore promotes the pumping effect of the capillary water retention layer 32 itself, enabling the water to be effectively supplied to the wet surface layer 3 in the manner shown in the figure.

[0037] (Fourth embodiment) As cross-sectional views showing the fourth embodiment of the pavement structure of the present invention, Fig. 9(a) shows the components of the pavement structure 1, Fig. 9(b) shows the configuration during rainfall, and Fig. 9(c) shows the configuration during fine weather. In the following, the components common to the first to third embodiments will be omitted.

[0038] As shown in Figure 9(a), a permeable surface layer 2 that forms a road surface is provided adjacent to the wet surface layer 3 of the first to third embodiments described above, and a permeable base layer 21 that can store water that has permeated through the permeable surface layer 2 is formed below the permeable surface layer 2. Furthermore, the permeable base layer 21 is connected to the capillary water retention layer 32 via a connector, so that water stored in the permeable base layer 21 can be guided to the capillary water retention layer 32 via the connector. Note that, although open-graded asphalt pavement can be suitably used for the permeable surface layer 2, any known pavement material can be used as long as it has water permeability.

[0039] The permeable base layer 21 of this embodiment is 250 mm thick and is made by evenly laying broken granite stones with a particle size of 50 to 150 mm and No. 5 crushed stone (with a particle size of 13 to 20 mm) as filler. In addition, this configuration of a portion of the permeable base layer 21 makes it possible to store water that has permeated the permeable surface layer 2 within the permeable base layer 21. Note that the constituent materials of the permeable base layer 21 are not necessarily limited to the above-mentioned particle sizes, and can be adjusted as appropriate as long as the particle size allows for smooth infiltration and storage of rainwater that has permeated the permeable surface layer 2 due to rainfall.

[0040] 9(a), the permeable base layer 21 and the capillary water retention layer 32 are connected via a connection part, and the water stored in the permeable base layer 21 can be guided to the capillary water retention layer 32 via the connection part. In this embodiment, the structure is such that water can be guided via a water-permeable sheet 60.

[0041] It should be noted that the capillary water retention layer 32 is not necessarily limited to a sheet-like one, and a water-permeable screen made of nylon, plastic, metal, etc. may also be installed. Furthermore, if a sandbag is used for the capillary water retention layer 32, the shape of the capillary water retention layer 32 is easily maintained and the outflow of sand is suppressed, so the sheet 60 is not necessarily required.

[0042] Next, the function of the pavement structure of this embodiment will be explained. As shown in Figure 9(b), rainwater during rainfall permeates the permeable surface layer 2 and infiltrates the permeable base course layer 21, where it is stored in the pores of the base course material. The stored rainwater gradually seeps into the roadbed, as indicated by the dashed arrows in the figure, and performs the function of a permeable pavement. Meanwhile, the rainwater stored in the permeable base course layer 21 is guided through the connections to the capillary water retention layer 32, where it is retained.

[0043] In this embodiment, as shown in each diagram of Figure 9, a rainwater drainage pipe 6 is provided to connect the capillary water retention layer 32 to a rainwater drainage facility (not shown). When a large amount of rainwater flows in due to heavy rain or the like and exceeds the water retention capacity that the capillary water retention layer 32 can tolerate, the water can be drained through the rainwater drainage pipe 6.

[0044] As shown in Figure 9(c), on sunny days, rainwater stored in the permeable roadbed layer 21 can be used to transport the moisture held in the capillary water retention layer 32 upward by capillary action, thereby supplying moisture to the wet surface layer 3.

[0045] The above-described configuration of this embodiment allows rainwater to penetrate into the roadbed during rainfall, fulfilling its inherent function as a permeable pavement, while utilizing the stored rainwater to continuously achieve the cooling effect of a wet pavement even on sunny days. In particular, as described above, the permeable pavement of this embodiment is capable of storing rainwater while allowing it to penetrate into the roadbed, ensuring sufficient storage capacity in the permeable base layer 21 by the time of the next rainfall, enabling it to function effectively during the heavy rains that have become more frequent in recent years. Furthermore, in both the wet pavement area and the permeable pavement area, the capillary water retention layer 32 and the permeable base layer 21 are constructed after the construction of the roadbed, respectively. In other words, the pavement has a cross-sectional structure that includes a roadbed and a roadbed, similar to those found on ordinary roads, allowing vehicles to pass through the pavement surface.

[0046] In addition, in this embodiment, a waterproof sheet 42 is installed on a portion of the bottom surface of the permeable roadbed layer 21 to form an impermeable area that prevents moisture stored in the permeable roadbed layer 21 from penetrating into the roadbed, and a permeable sheet 41 is installed to form a permeable area that allows moisture stored in the permeable roadbed layer 21 to penetrate into the roadbed.

[0047] This configuration, as shown in Figure 9(b), limits the amount of rainwater seeping from the permeable base layer 21 into the subgrade, allowing it to be guided to the capillary water retention layer 32 for a longer period of time and supply moisture to the wet surface layer 3. Furthermore, by setting the ratio of the impermeable sheet 42 and the permeable sheet 41 on the bottom surface of the permeable base layer 21 based on the current ground permeability and the on-site drainage design, it is possible to finely adjust the amount of rainwater stored in the permeable base layer 21. Additionally, by using both the impermeable sheet 42 and the permeable sheet 41, rainwater can be guided to the pumping layer 31 in fine weather in the permeable base layer 21, while allowing some of the rainwater to seep into the subgrade during heavy rain, preventing flooding of the road surface. Furthermore, installing the permeable sheet 41 in the permeable area effectively prevents subgrade soil from seeping into the permeable base layer 21, thereby suppressing deterioration over time in permeability and water storage capacity.

[0048] (Fifth embodiment) Next, a modified example of the above-described embodiment is shown in Figure 10. In the following, the configuration common to the above-described first to fourth embodiments will be omitted. That is, as shown in Figure 10(a), the connection part is provided with a water-conducting member 50 that can conduct water stored in the permeable base layer 21 to the capillary water retention layer 32, and one side of the water-conducting member 50 is connected to the capillary water retention layer 32 or the reservoir layer 33, and the other side is connected to the impermeable region of the permeable base layer 21 (the installation region of the illustrated waterproof sheet 42).

[0049] With this configuration, even if, for example, a curb or a planting strip is constructed on the ground between the wet pavement area and the permeable pavement area, it is possible to reliably conduct the water stored in the permeable roadbed layer 21 to the capillary water retention layer 32 via the installed water-conducting member 50, as shown in Figures 10(b) and (c).

[0050] In this embodiment, a hard vinyl pipe with an inner diameter of 40 mm is used as the water conducting member 50, but the specification is not necessarily limited to this. For example, it is possible to change the specification appropriately depending on the number of installation locations of the water conducting member 50, the area of ​​the wet pavement area, the area of ​​the permeable pavement area, etc., so as to ensure the amount of water conducting required for the wet pavement to function normally.

[0051] (Sixth embodiment) Next, Fig. 11 shows a modified example of the above-described embodiment. In the following, the configuration common to the first to fifth embodiments will be omitted. That is, as shown in Fig. 11(a), the connecting portion is provided with a bottom water-conducting member 51 that can conduct water stored in the permeable base layer 21 to the capillary water retention layer 32, and that has one end connected to the capillary water retention layer 32 and the other end connected to the impermeable region of the permeable base layer 21 (the installation area of ​​the illustrated water-shielding sheet 42), and an upper water-conducting member 52 that is provided above the bottom water-conducting member 51 and that has one end connected to the capillary water retention layer 32 and the other end connected to the impermeable region of the permeable base layer 21 (the installation area of ​​the illustrated water-shielding sheet 42).

[0052] With this configuration, even if, for example, a curb or a planting strip is constructed on the ground between the wet pavement area and the permeable pavement area, it is possible to reliably conduct the water stored in the permeable roadbed layer 21 to the capillary water retention layer 32 via the installed bottom water conduction member 51 and upper water conduction member 52, as shown in Figures 11(b) and (c).

[0053] Furthermore, by providing an upper water conduction member 52 above the bottom water conduction member 51, as can be seen from the state during rainfall shown in Figure 11 (b), when a large amount of rainwater is stored in the permeable roadbed layer 21, rainwater will also be conducted from the upper water conduction member 52 to the capillary water retention layer 32, making it possible to quickly conduct water to the capillary water retention layer 32.

[0054] In particular, when there is heavy rainfall and the water cannot permeate the roadbed in time, the upper water-conducting member 52 makes it possible to drain the rainwater through the capillary water retention layer 32 and further through the capillary water retention layer 32 to the rainwater drainage pipe 6, thereby maintaining the permeability function of the permeable pavement area in good condition.

[0055] 11(a), in this embodiment, the cross-sectional area of ​​the upper water-conducting member 52 is made larger than the cross-sectional area of ​​the bottom water-conducting member 51. With this configuration, when a large amount of rainwater is stored in the permeable base layer 21 due to heavy rain or the like, it is possible to quickly reduce the amount of rainwater stored in the permeable base layer 21, and the permeability of the permeable pavement area can be maintained at a good level.

[0056] Seventh embodiment Next, Figures 12 and 13 show modified examples of the above-described embodiments. In the following, configurations common to the first to sixth embodiments will be omitted. That is, by forming a slope on the bottom surface of the permeable roadbed layer 21 as shown in Figure 12(a) or by forming a step on the bottom surface of the permeable roadbed layer 21 as shown in Figure 13(a), the height of the bottom surface of the permeable roadbed layer 21 in the impermeable region (the area where the illustrated waterproof sheet 42 is installed) is configured to be lower than the height of the bottom surface of the permeable roadbed layer 21 in the permeable region (the area where the illustrated waterproof sheet 41 is installed).

[0057] With this configuration, rainwater can be collected in the impermeable area (the area where the waterproof sheet 42 is installed in the figure) and a predetermined amount of rainwater can be stored without permeating into the roadbed. This makes it possible to reliably store a predetermined amount of rainwater and continuously supply moisture to the wet surface layer 3 even when there has been no rainfall for some time.

[0058] (Eighth embodiment) Next, a modified example of the above-described embodiment is shown in Figure 14. In the following, the configuration common to the above-described first to seventh embodiments will be omitted. That is, as shown in Figure 14(a), inlet closing means 8 is provided that can close the inlet of the upper water guide member 52, and the inlet of the upper water guide member 52 can be opened and closed depending on the amount of water stored in the permeable roadbed layer 21.

[0059] To explain in more detail, as shown in Figure 14(a), a water-permeable screen 81 is provided to form a predetermined space around the inlet of the upper water guide member 52, and a buoyant inlet blocking means 8 is installed in the predetermined space.

[0060] When the amount of water stored in the permeable roadbed layer 21 exceeds a predetermined amount due to rainfall or other reasons, the inlet blocking means 8 moves upward as shown in Figure 14(b), the inlet of the upper water guide member 52 is opened, and the stored rainwater is guided into the capillary water retention layer 32.

[0061] On the other hand, as shown in Figure 14(c), when the amount of water stored in the permeable subgrade layer 21 falls below a predetermined amount, the inlet blocking means 8 moves downward and closes the inlet of the upper water guide member 52.

[0062] This configuration makes it possible to prevent the rainwater stored in the permeable roadbed layer 21 from being excessively guided to the capillary water retention layer 32, and enables the bottom water guide member 51 to gradually and continuously supply the required amount of moisture to the wet surface layer 3.

[0063] (Ninth embodiment) Next, Figure 15 illustrates a modified example of the aforementioned embodiment, and Figure 15(b) is a plan view of Figure 13(a). The following description will omit the components common to the first through eighth embodiments. Specifically, as shown in Figure 15(b), multiple bottom water-conducting members 51 are provided at predetermined intervals, and water treatment materials capable of removing nutrients are installed inside the bottom water-conducting members 51. Examples of water treatment materials that can be used include Kanto loam granules, oyster shells, magnesium, aluminum, limestone, activated carbon, wood charcoal, and zeolite, either singly or in combination. This configuration allows rainwater that has permeated and accumulated through the permeable pavement area to be purified and supplied to the wet pavement area.

[0064] (Tenth embodiment) Next, Fig. 16 shows a modified example of the above-described embodiment. The following description will omit components common to the first to ninth embodiments. Specifically, it is possible to provide a water-conducting sheet 35 and a water supply pipe 34 capable of supplying water to the water-conducting sheet 35 below the wet surface course 3. With this configuration, even if, for example, a series of sunny days causes the rainwater stored in the permeable base course layer 21 and the water retained in the capillary water retention layer 32 to run out, tap water or the like can be supplied to the water supply pipe 34 to supply water to the water-conducting sheet 35, allowing the wet pavement area to continue functioning.

[0065] An observation well (not shown) may be provided in the permeable base layer 21, and the water supply to the water supply pipe 34 may be controlled manually or automatically depending on the amount of rainwater stored. This configuration makes it possible to efficiently use the stored rainwater, reduce water supply costs, and continuously maintain the functionality of the wet pavement area.

[0066] 16 shows an embodiment in which the permeable pavement area is a roadway and the wet pavement area is a sidewalk, etc. This configuration makes it possible to cool the surface temperature of the sidewalk, etc. on sunny days, and is effective as a heat countermeasure for pedestrians, pets, wheelchair users, etc. Note that the wet pavement area is not limited to the above-mentioned sidewalk, but can also be applied to parks, building exteriors, parking lots, etc.

[0067] (Eleventh embodiment) As cross-sectional views showing the eleventh embodiment of the pavement structure of the present invention, Fig. 17(a) shows a cross-sectional view showing the state during rainfall, and Fig. 17(b) shows a cross-sectional view showing the state during fine weather. In the following, the configurations common to the first to tenth embodiments will be omitted.

[0068] As shown in Figure 17(a), below the wet surface layer 3 is provided a reservoir layer 33 in which a rainwater storage space is formed by a capillary water retention layer 32 and a concrete structure 9. Furthermore, a pumping member 7 is installed from the reservoir layer 33 to the capillary water retention layer 32, and a protective pipe equipped with a screen is installed around the boundary between the reservoir layer 33 of the pumping member 7 and the capillary water retention layer 32 to protect the pumping member 7 and to prevent sand in the capillary water retention layer 32 from flowing out into the reservoir layer 33.

[0069] During rainfall, as shown in Figure 17(a), rainwater is allowed to infiltrate and be retained in the capillary water retention layer 32 via the wet surface layer 3, and can then be stored in the storage layer 33 via a protective pipe or the like. As in the previously described embodiment, an upper water conducting member 52 and a bottom water conducting member 51 may be connected to the storage layer 33, and rainwater stored in the permeable roadbed layer 21 of the permeable pavement area may be supplied. Furthermore, if heavy rain or prolonged rain causes the rainwater storage capacity of the storage layer 33 to be exceeded, the rainwater may be drained via the rainwater drainage pipe 6 as shown in the figure.

[0070] On sunny days, as shown in Figure 17(b), capillary action allows capillary water to be supplied to the wet surface layer 3 by the capillary water retention layer 32 and the pumping member 7, and moisture stored in the reservoir layer 33 can be used to continuously supply moisture to the wet surface layer 3.

[0071] (Twelfth embodiment) As cross-sectional views showing the twelfth embodiment of the pavement structure of the present invention, Fig. 18(a) shows a cross-sectional view showing the state during rainfall, and Fig. 18(b) shows a cross-sectional view showing the state during fine weather. In the following, the configurations common to the first to eleventh embodiments will be omitted.

[0072] 18(a), a capillary water retention layer 32 is provided below the wet surface layer 3. Furthermore, a plurality of pumping members 7 are installed in the approximately vertical direction inside the capillary water retention layer 32. In this embodiment, the pumping members 7 are rod-shaped members with high thermal conductivity made of copper, aluminum, or the like.

[0073] During rainfall, as shown in Figure 18(a), rainwater can penetrate and be retained in the capillary water retention layer 32 via the wet surface layer 3. During fine weather, as shown in Figure 18(b), heat moves from the top to the bottom of the water pumping member 7 as the temperature of the wet surface layer 3 rises. This promotes capillary action, enabling the capillary water retained in the capillary water retention layer 32 to be quickly supplied to the wet surface layer 3.

[0074] Although the embodiments of the present invention have been described above, they can be implemented in combination with each other.

[0075] (Other embodiments) The pavement structure of the present invention is not necessarily limited to the above-described embodiment and each modified example, and the following modifications are possible.

[0076] For example, in the connection parts shown in Figures 10, 11, and 13 to 16, it is possible to provide a manhole or a U-shaped gutter that can be accessed from above ground, and to install the water guide member 50, bottom water guide member 51, and upper water guide member 52 inside these. Such a configuration makes it possible to easily replace and maintain each water guide member.

[0077] Furthermore, the aforementioned water conducting member 50, bottom water conducting member 51, and upper water conducting member 52 can be selected as appropriate, and PVC pipes, flexible hoses, water conducting pipes made of woven fiber material, water conducting mats made of nonwoven fabric and braided cord, etc. In other words, each water conducting member is not limited to those that transport water using gravity, but those that conduct water using capillary action can also be used.

[0078] Furthermore, in the above-described embodiment, as shown in Figures 9 to 16, a permeable surface layer 2 is provided adjacent to the wet surface layer 3 to form a road surface, and a permeable roadbed layer 21 capable of storing water that has permeated through the permeable surface layer 2 is formed below the permeable surface layer 2, and the rainwater stored in the permeable roadbed layer 21 is guided to the capillary water retention layer 32 via a connection part. However, the present invention is not necessarily limited to such an embodiment.

[0079] For example, a water tank (not shown) can be provided above or below ground outside the wet pavement area, and moisture can be conducted from the outside via a connection connected to the capillary water retention layer 32 or the reservoir layer 33 below the wet surface layer 3. The water tank can also store tap water, not just rainwater. This configuration reduces the cost and effort required to install the permeable surface layer 2 and the permeable base layer 21, while enabling the water tank to continuously and stably supply moisture to the capillary water retention layer 32 and the reservoir layer 33.

[0080] The embodiments and various modifications of the present invention have been described above, but the scope of the present invention is defined by the claims rather than the above-described embodiments, and includes all modifications within the meaning and scope of the claims. Furthermore, the specific materials, dimensions, shapes, etc. described in the above-described embodiments can be modified within the scope of solving the problems of the present invention. [Explanation of symbols]

[0081] 1. Pavement structure 2 Permeable surface layer 3. Wet surface 6 Rainwater drainage piping 7. Pumping components 8 Inlet closing means 21 Permeable roadbed 31 Water conveyance layer 32 Capillary water retention layer 33 Reservoir 41 Permeable sheet 42 Water-resistant sheet 50 Water conduction members 51 Bottom water conducting member 52 Upper water conduction member 60 sheets 71 Hollow part 72 Pumping Wall 81 screens

Claims

1. a wet surface layer that forms a road surface and has water absorption and permeability; a capillary water retention layer provided below the wet surface layer and made of sand having water lifting and permeability and capable of retaining capillary water; a plurality of pumping members independently provided inside the capillary water retention layer, each of which is capable of supplying moisture to the wet surface layer by capillary action; a water-blocking member provided on the bottom surface of the capillary water retention layer; During rainfall, rainwater penetrates into the capillary water retention layer through the wet surface layer and is retained therein, and during fine weather, the capillary water can be supplied to the wet surface layer by the capillary water retention layer and the water pumping member due to capillary action. the pumping member is disposed vertically from the upper surface of the water-blocking member and has a pumping speed greater than that of the capillary water retention layer; a connecting portion connected to the capillary water retention layer, the capillary water retention layer is capable of conducting moisture from the outside through the connection portion; The exterior has a permeable surface layer having water permeability, and a permeable base layer provided below the permeable surface layer to store water that has permeated through the permeable surface layer. A pavement structure characterized by:

2. The pumping member is The pumping member has a hollow portion extending vertically to the upper end thereof, and a pumping wall formed around the hollow portion and capable of pumping water by capillary action. The pavement structure of claim 1.

3. a wet surface layer that forms a road surface and has water absorption and permeability; a capillary water retention layer provided below the wet surface layer and made of sand having water lifting and permeability and capable of retaining capillary water; a reservoir layer provided below the capillary water retention layer and having a water retention rate higher than that of the capillary water retention layer; a plurality of pumping members independently provided inside the capillary water retention layer and the reservoir layer, and capable of supplying moisture to the wet surface layer by capillary action; a water-blocking member provided on the bottom surface of the reservoir; During rainfall, rainwater is allowed to penetrate and be retained in the capillary water retention layer and the reservoir through the wet surface layer, and during fine weather, the capillary water can be supplied to the wet surface layer by the capillary water retention layer and the pumping member due to capillary action. the pumping member is disposed vertically from the upper surface of the water-blocking member and has a pumping speed greater than that of the capillary water retention layer; a connection portion connected to the reservoir; The reservoir can conduct water from the outside through the connection portion, The exterior has a permeable surface layer having water permeability, and a permeable base layer provided below the permeable surface layer to store water that has permeated through the permeable surface layer. A pavement structure characterized by:

Images