JP2001073307A - Water permeable pavement structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water permeable pavement structure capable of being used for a roadway having comparatively heavy traffic, maintaining infiltration capacity for a comparatively long period of time and controlling the deterioration and softening of pavement itself. SOLUTION: The water permeable pavement structure is equipped with a cement stabilized water retentive subgrade 11, a water permeable binder course 13 of open-graded asphalt concrete, a cushion layer 14 of sand or No. 7 crushed stone and a drainable interlocking block layer 16. The binder course 13 has 1000-2000 times/mm of dynamic stability, and the block layer 16 is formed by constructing an interlocking block 16a having flexural strength higher than 3.5 N/mm2 and having skid resistance higher than 60 BPN. A cement stabilized water permeable base 12 having thickness of 20-30 cm is formed on the subgrade 11, and the binder course 13 is formed on the base 12. The base has coefficient of water permeability of 1×10-4-1×10-3 cm/s, and unconfined compressive strength has 10-30 kgf/cm2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permeable pavement structure for allowing water on a road surface to penetrate into a subgrade.

[0002]

2. Description of the Related Art Drainable pavements and water-permeable pavements have been known as pavement structures capable of penetrating water on a road surface. Drainable pavement is intended to drain rainwater from the road surface.The asphalt mixture for drainage pavement is used for the surface layer or the surface layer and the middle layer, and the structure is such that water does not penetrate below the base layer. is there. On the other hand, the permeable pavement has a structure in which the water on the road surface penetrates to the subgrade. Since such drainage pavement and water-permeable pavement allow the water on the road surface to penetrate, the hydroplaning phenomenon is suppressed, the splash of water during rainfall is reduced, and the visibility during traveling on rainy weather is secured, and the road surface is covered with water. This has the effect of reducing traffic noise due to the air pumping phenomenon and preventing the temperature of the road surface from rising due to evaporation of the permeated water.

[0003]

However, in the drainage pavement, since water does not permeate below the base layer, it is necessary to drain the water permeating the surface layer or the surface layer and the intermediate layer from the road surface to another place. However, there is a problem that the structure for draining the water to another place becomes relatively complicated. In addition, voids in the surface layer or the surface layer and the intermediate layer where the water temporarily stagnates are relatively easily clogged with dust and the like contained in the water, and the repair cycle of the surface layer or the surface layer and the intermediate layer based on a decrease in the water penetration capacity. Is relatively short. On the other hand, in the case of permeable pavement, the drainage structure of water that permeates water to the subgrade under the roadbed is relatively simple, but there is a problem that the pavement itself is deteriorated and softened due to recharge of rainwater. Since the permeable pavement has a structure in which water penetrates to the roadbed, if the pavement is deteriorated and softened, there is a problem that maintenance and repair thereof require a large cost. Due to such properties, the conventional permeable pavement is used exclusively for the sidewalk and the light traffic section, and is not used for the road with relatively large traffic. An object of the present invention is to provide a permeable pavement structure that can be used on a road with relatively heavy traffic. Another object of the present invention is to provide a water-permeable pavement structure capable of maintaining the ability to penetrate for a relatively long time and suppressing deterioration and softening of the pavement itself.

[0004]

The invention according to claim 1 is
As shown in FIG.
water-retentive subgrade 11 having a thickness of 5 cm, and 5 to 10 cm made of asphalt concrete having an open particle size formed on the subgrade 11
, A cushion layer 14 made of sand or No. 7 crushed stone formed on the base layer 13, a cushion layer 14 having a thickness of 1 to 3 cm, and 6 to 15 cm formed on the cushion layer 14.
And a drainage interlocking block layer 16 having a thickness of 5 mm. According to the first aspect of the present invention, the water that has poured onto the surface of the interlocking block layer 16 due to rainfall is
Of the roadbed 12 through the cushion layer 14
The roadbed 12 plays a role of a conventional water-permeable pavement in which the water permeated from the base layer 13 is promptly penetrated to the roadbed 11. In addition, since the water-permeable base layer 13 having a thickness of 5 to 10 cm is formed on the roadbed 11, it can be used on a road with relatively large traffic volume, and drainage interlocking is performed on the base layer 13 via the cushion layer 14. Since the block layer 16 is formed, the water permeability can be maintained for a long time as compared with the conventional water-permeable pavement structure in which the surface layer is made of water-permeable asphalt.

The invention according to claim 2 is the invention according to claim 1, wherein the roadbed 11 has a hydraulic conductivity of 1 × 10 ^-5 to 1 × 1.
0 ⁻³ cm / s, and the base layer 13 has a water permeability of 1 × 10 ^−2.
cm / s or more and the dynamic stability is 1000 to 2000
Times / mm, and the interlocking block layer 16 has a water permeability of 1 × 10 ⁻¹ cm / s or more and a porosity of 2
This is a water-permeable pavement structure formed by laying an interlocking block 16a having a bending strength of 5 to 30%, a bending strength of 3.5 N / mm ² or more, and a slip resistance of 60 or more in BPN. According to the second aspect of the present invention, the water poured on the surface of the interlocking block layer 16 can smoothly penetrate into the water-retentive roadbed 11 and be reduced from the roadbed 11 into the ground. The bending strength of the interlocking block 16a is 3.5N /
mm ² or more and the slip resistance is 60 or more in BPN, so that even on a road where a relatively large number of vehicles run, the block 16a itself is not damaged and the base layer 13
Since the dynamic stability of the vehicle is 1000 to 2000 times / mm, rutting caused by traffic of a large vehicle is suppressed, and the vehicle can be used on a road with a relatively large traffic volume.

A third aspect of the present invention is the invention according to the first or second aspect, wherein a cement-stabilized water-permeable roadbed 12 having a thickness of 20 to 30 cm is formed on a subgrade 11.
This is a water-permeable pavement structure in which a base layer is formed on the roadbed 12.
According to the third aspect of the present invention, the water permeable roadbed 12 formed on the roadbed 11 is the base layer 1 formed on the roadbed 12.
3 and the interlocking block layer 16 are maintained satisfactorily for a relatively long period of time to suppress deterioration and softening of the pavement itself. The invention according to claim 4 is the invention according to claim 3, wherein the roadbed 12 has a water permeability of 1 × 10 ⁻⁴ to 1 × 10 ^4.
-3 cm / s and a uniaxial compressive strength of 10 to 30 kgf /
cm ² is a permeable pavement structure.

In the invention according to claim 4, the uniaxial compressive strength of the roadbed 12 is set to 10 to 30 kgf / cm ² ,
Provided is a pavement structure that can be used on a road in so-called C traffic where the traffic volume of large vehicles is less than 3000 vehicles per day. In addition, since the water permeability is set to 1 × 10 ⁻⁴ to 1 × 10 ⁻³ cm / s, the roadbed 12 allows the water permeating from the base layer 13 to quickly permeate to the roadbed 11. The invention according to claim 5 is the invention according to claim 3 or 4, wherein the roadbed 11 is subjected to cement stabilization by mixing incineration ash of papermaking sludge, the roadbed 12 is mixed with incineration ash of papermaking sludge, and recycled concrete is used. It is a permeable pavement structure that has been cement stabilized using crushed stone. According to the fifth aspect of the present invention, since the paper bed sludge incineration ash is mixed and the roadbed 11 and the roadbed 12 are subjected to the cement stabilization treatment, the economic efficiency is improved.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. As shown in FIG. 1, the permeable pavement structure 10 of the present invention has a water-retentive roadbed 11 having a thickness of 30 to 80 cm, which is subjected to a cement stabilization treatment at the lowermost layer. If the thickness of the subgrade 11 is less than 30 cm, sufficient water retention cannot be secured, and if it exceeds 80 cm, the construction cost increases. Water-retentive subgrade 11 in this embodiment
Is prepared by premixing a predetermined amount of papermaking sludge incineration ash with cement cement-solidifying material, stabilizing the cement, and improving the subgrade 11 to make the subgrade 11 water-retentive. Its permeability is 1 × 10 ^−. It is adjusted to ⁵ to 1 × 10 ⁻³ cm / s. This water permeability is particularly preferably 1 × 10 ⁻⁴ cm / s or more. When the water permeability is less than 1 × 10 ⁻⁵ cm / s, there is a problem in good permeability of rainwater.

On the roadbed 11, cement stabilized 2
A permeable roadbed 12 having a thickness of 0 to 30 cm is formed. If the thickness of the roadbed 12 is less than 20 cm, there is a problem that the supporting force is insufficient, and if it exceeds 30 cm, there is a problem that the construction cost increases. 100% recycled concrete crushed stone is used for the roadbed 12, a predetermined amount of paper sludge incineration ash is premixed with ordinary cement as a solidifying material, and the cut crushed stone used for ordinary permeable pavement on the road recycled recycled cement stabilized treatment roadbed 12 By adding the above water permeability function, the water permeability coefficient is adjusted to 1 × 10 ⁻⁴ to 1 × 10 ⁻³ cm / s, and the uniaxial compressive strength is adjusted to 10 to 30 kgf / cm ² . If the water permeability is less than 1 × 10 ⁻⁴ cm / s, there is a problem that good rainwater penetration is hindered. The uniaxial compressive strength is particularly 2
0 kgf / cm ² or more is preferable. If the uniaxial compressive strength is less than 10 kgf / cm ² , there is a problem that the supporting force is insufficient, and if it exceeds 30 kgf / cm ² , there is a problem that the construction cost increases.

On the roadbed 12, a water-permeable base layer 1 of 5 to 10 cm in thickness made of open grain asphalt concrete is provided.
3 is formed. If the thickness of the water-permeable base layer 13 is less than 5 cm, there is a problem that the supporting force is insufficient, and if it exceeds 10 cm, there is a problem that the construction cost increases. The base layer 13 is asphalt concrete in which a water-permeable asphalt mixture is compacted. As the asphalt mixture, an open particle size mixture containing almost no sand is used to improve the porosity. The base layer 13 has a water permeability of 1 ×
10 ⁻² cm / s or more and dynamic stability of 1000 to 2
It is adjusted to 000 times / mm. This coefficient of permeability is 1 × 10
^If it is less than ^-2 cm / s, there is a problem that the penetration of rainwater is hindered. The dynamic stability is particularly preferably 1500 times / mm or more. If the dynamic stability is less than 1000 times / mm, there is a problem that sufficient durability cannot be obtained.

On this base layer 13, a cushion layer 14 made of sand or No. 7 crushed stone and having a thickness of 1 to 3 cm is formed.
The thickness of the cushion layer 14 is particularly preferably 2 cm.
If the thickness of the cushion layer 14 is less than 1 cm or more than 3 cm, there is a problem that sufficient flatness and durability of the drainage interlocking block layer 16 described later cannot be obtained. On the cushion layer 14, a drainage interlocking block layer 16 having a thickness of 6 to 15 cm is further formed. This drainage interlocking block layer 16
Is particularly preferably 8 cm. If the thickness of the block layer 16 is less than 6 cm, sufficient durability cannot be obtained, and if it exceeds 15 cm, the construction cost increases.

Drainable interlocking block layer 16
Is constructed by laying a plurality of interlocking blocks 16a on the cushion layer 14, and the interlocking blocks 16a have a water permeability of 1 × 10 ⁻¹ cm /
s or more, a porosity of 25 to 30%, a bending strength of 3.5 N / mm ² or more, and a slip resistance of 60 or more in BPN are used. This coefficient of permeability is 1 × 10
^If it is less than ^-1 cm / s, there is a problem that good rainwater permeability cannot be obtained. Further, if the porosity is less than 25%, it is relatively easy to be clogged with dust or the like contained in water,
There is a problem that the water permeation ability is reduced early, and if it exceeds 30%, there is a problem that the durability of the interlocking block 16a is reduced. This bending strength is 3.5 N / mm
^If it is less than ² , there is a problem that the bearing capacity of a large vehicle is exerted. Further, the slip resistance is particularly preferably 65 or more in BPN. If the slip resistance is less than 60 in BPN, the slip resistance is reduced, and there is a problem that the slip of the vehicle running on the drainable interlocking block layer 16 cannot be effectively prevented.

In the water-permeable pavement structure thus configured, the water permeability of the interlocking block 16a in the interlocking block layer 16 is 1 × 10 ⁻¹ c.
m / s or more and the porosity is 25 to 30%,
The water that has fallen on the surface of the interlocking block layer 16 due to the rainfall penetrates into the cushion layer 14 from the gap of the interlocking block 16a itself or the gap between the block 16a and the block 16a, and further reaches the base layer 13.
Here, since the bending strength of the interlocking block 16a is 3.5 N / mm ² or more and the slip resistance is 60 or more in BPN, the block 16 a itself can be used even on a road on which a relatively large number of vehicles run. No damage.

The base layer 13 has a water permeability of 1 × 10 ^-2 cm / s.
As described above, the base layer 13 allows the water that has permeated from the interlocking block layer 16 through the cushion layer 14 to smoothly penetrate into the roadbed 12,
It also functions as a water retention layer for road surface flooding control during heavy rains. Here, the dynamic stability of the base layer 13 is set to 1000 to 2
Since the adjustment is performed at 000 times / mm, rutting caused by the traffic of a large vehicle is suppressed, and the vehicle can be used on a road with a relatively large traffic volume.

The roadbed 12 has a permeability of 1 × 10 ^-4 to 1 × 1.
Since it is 0 ⁻³ cm / s, the roadbed 12 allows the water that has permeated from the base layer 13 to quickly permeate the roadbed 11. Further, the uniaxial compressive strength of the roadbed 12 is set to 10 to 30 kgf / cm.
² so that the base layer 1 formed on the roadbed 12
3 and the interlocking block layer 16 are maintained well for a relatively long time. The water that has permeated the water-retentive roadbed 11 is returned from the roadbed 11 into the ground. Especially the subgrade 11
Is adjusted to 1 × 10 ⁻⁵ to 1 × 10 ⁻³ cm / s, the subgrade 11 can smoothly reduce the water that has penetrated to the roadbed 12 into the ground.

[0016]

Next, examples of the present invention will be described in detail together with comparative examples. <Example 1> As shown in FIG. 1, a cement-stabilized design CBR forms a cement-stabilized 20 cm thick permeable roadbed 12 on a water-retentive roadbed 11, and further comprises An 8 cm thick water-permeable base layer 13 made of open-grain asphalt concrete was formed on the roadbed 12. At this time, the water permeability of the water-retentive roadbed 11 is 2.2 × 1.
0 ^-4 cm / s, and the permeability of the roadbed 12 is 4.9 × 1
0 ^-4 cm / s and the uniaxial compressive strength is 23 kgf / cm
^{Was 2} . The water permeability of the base layer 13 is 3.7 × 10
It was ^-2 cm / s, and the dynamic stability was 1500 times / mm. A 2 cm thick cushion layer 14 made of crushed stone No. 7 is formed on the base layer 13, and an interlocking block 16 a having a thickness of 8 cm is laid on the cushion layer 14 to form a drainage interlocking block layer 16. did. The interlocking block 16a has a water permeability of 2 × 10 ⁻¹ cm / s, a porosity of 28%, a bending strength of 4.1 N / mm ² , and a slip resistance of BP.
N at 75 was used.

Comparative Example 1 A cement-stabilized 20 cm thick permeable roadbed 12 having a cement-stabilized design was formed on a water-retentive roadbed 11 having a cement-stabilized design CBR of 12 by the same procedure as in Example 1. did. A 2 cm thick cushion layer 14 made of No. 7 crushed stone is formed on the roadbed 12 in the same manner as in the first embodiment, and the same interlocking block 16 a as in the first embodiment is laid on the cushion layer 14 to drain water. A functional interlocking block layer 16 was formed.

<Comparative Test and Evaluation> The deflection on the surface of the water-permeable base layer 13 in Example 1 and the deflection on the surface of the drainable interlocking block layer 16 in Example 1 and Comparative Example 1 were measured by using a falling weight deflector ( FWD). Note that the deflection of the surface of the water-permeable base layer 13 in Example 1 was measured before forming the cushion layer 14 in Example 1. As a result, as shown in FIG. 2, the deflection on the surface of the water-permeable base layer 13 in Example 1 was 0.190 mm, the deflection on the surface of the drainable interlocking block layer 16 in Example 1 was 0.185 mm, and The deflection of the surface of the drainage interlocking block layer 16 is 1.23.
2 mm.

Since the deflection of the surface of the water-permeable base layer 13 in Example 1 is 0.190 mm, it can be understood that the base layer 13 alone can be used on a road with a relatively large traffic volume. Therefore, it is understood that the present invention can be sufficiently realized if the interlocking block 16a can sufficiently withstand the running of the vehicle. This is proved by the fact that the surface of the drainage interlocking block layer 16 of Example 1 using the interlocking block 16a having a bending strength of 4.1 N / mm ² capable of withstanding the running of the vehicle has a deflection of 0.185 mm. Was. Here the traffic volume of large vehicles is 300
In a so-called C traffic road with less than 0 vehicles, it is generally required that this deflection is 0.4 mm or less as shown by a dashed line in FIG. Therefore, it can be seen that the pavement structure in Example 1 can be used for the roadway in the C traffic.

On the other hand, in Comparative Example 1 showing a water-permeable pavement using a conventional interlocking block 16a having no base layer 13, the surface of the drainage interlocking block layer 16 had a deflection of 1.232 mm. As is clear from these figures, it can be understood that the conventional permeable pavement structure is not used for a road with a relatively large traffic volume, but is used exclusively for a sidewalk or a light traffic portion.

[0021]

As described above, the water-permeable pavement structure of the present invention comprises a water-retentive roadbed, a water-permeable base layer formed on open-grade asphalt concrete, and a cushion layer formed on the base layer. And a drainage interlocking block layer formed on the cushion layer,
A conventional permeable pavement structure in which the surface of the interlocking block layer serves as a conventional permeable pavement that allows the water on the surface of the interlocking block layer to penetrate into the subgrade, and is used on roadways with relatively high traffic volume. Can maintain the permeation ability over a long period of time.

The hydraulic conductivity of the subgrade 11 is 1 × 10 ⁻⁵ or ^less .
1 × 10 ⁻³ cm / s, and the water permeability of the base layer is 1 × 10 ⁻³ cm / s.
^-2 cm / s or more and dynamic stability is 1000 to 200
0 times / mm, the water permeability of the interlocking block layer is 1 × 10 ⁻¹ cm / s or more, and the porosity is 25.
If it is formed by laying an interlocking block 16a having a bending strength of 3.5 N / mm ² or more and a slip resistance of 60 or more in BPN, water flowing down to the surface of the interlocking block layer can be obtained. Water into the water-retentive subgrade smoothly, effectively reducing this water from the subgrade to the ground, and reducing rutting caused by the passage of large vehicles to use on roads with relatively heavy traffic. Can be made possible. Furthermore, the hydraulic conductivity is 1
Forming a cement-stabilized 20-30 cm thick permeable roadbed having a thickness of 10 ^-4 -1x10 ^-3 cm / s and a uniaxial compressive strength of 10-30 kg / cm ² on a roadbed;
If a base layer is formed on the roadbed, the base layer and the interlocking block layer formed on the roadbed are maintained satisfactorily for a relatively long period of time to suppress the deterioration and softening of the pavement itself, thereby reducing heavy vehicle traffic. Thus, it is possible to provide a pavement structure that can be used on a road in so-called C traffic of less than 3000 vehicles.

[Brief description of the drawings]

FIG. 1 is a sectional view of a road showing a pavement structure of the present invention.

FIG. 2 is a diagram showing the amount of deflection in an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Water-retentive subgrade 12 Water-permeable base 13 Water-permeable base layer 14 Cushion layer 16 Drainage interlocking block layer 16a Interlocking block

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazumi Hanaki 3400-1, Kuragano-cho, Takasaki-shi, Gunma Prefecture, Tokyo Hoso Kogyo Co., Ltd. (72) Inventor Yoshihito Kuroiwa 1-297 Kitabukurocho, Omiya-shi, Saitama Material Co., Ltd. Cement Research Institute (72) Inventor Taichi Imahashi 1-297 Kitabukuro-cho, Omiya-shi, Saitama Mitsubishi Materials Co., Ltd. Cement Research Institute (72) Inventor Koichi Kawabata 1-5-1 Marunouchi, Chiyoda-ku, Tokyo Materials Co., Ltd. F-term in cement and building materials company (reference) 2D051 AA02 AA08 AD08 AF01 AF03 AG01 AH03 DA04 EA02

Claims (5)

[Claims] 1. 30-80 cm cement stabilized
A water-retentive subgrade (11) having a thickness of 5 to 10 cm formed on the subgrade (11) and made of open-grade asphalt concrete
Water-permeable base layer (13), a cushion layer (14) having a thickness of 1-3 cm made of sand or No. 7 crushed stone formed on the base layer (13), and on the cushion layer (14). 6- formed in
Drainable interlocking block layer 15cm thick
(16) A permeable pavement structure comprising: 2. The roadbed (11) has a permeability of 1 × 10 ^-5 to 1 ×.
10 ⁻³ cm / s, and the base layer (13) has a water permeability of 1 × 10
^-2 cm / s or more and dynamic stability is 1000 to 200
0 times / mm, interlocking block layer (16)
Is interlocking having a water permeability of 1 × 10 ⁻¹ cm / s or more, a porosity of 25 to 30%, a bending strength of 3.5 N / mm ² or more, and a slip resistance of 60 or more in BPN. The permeable pavement structure according to claim 1, wherein the permeable pavement structure is formed by laying a block (16a). 3. A cement-stabilized 2 on a subgrade (11).
The permeable pavement structure according to claim 1 or 2, wherein a permeable roadbed (12) having a thickness of 0 to 30 cm is formed, and a base layer is formed on the roadbed (12). 4. The roadbed (12) has a hydraulic conductivity of 1 × 10 ^-4 to 1 ×.
10 ^-3 cm / s and uniaxial compressive strength of 10 to 30 kg
The permeable pavement structure according to claim 3, wherein f / cm ² is f / cm ² . 5. A roadbed (11) mixed with papermaking sludge incineration ash for cement stabilization, and a roadbed (12) mixed with papermaking sludge incineration ash and cement stabilized using recycled concrete crushed stone. The permeable pavement structure according to 3 or 4.