JP2008156944A - Road pavement structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a road pavement structure capable of obtaining a large quantity of water retained. <P>SOLUTION: This road pavement structure is composed of a surface layer 1, a roadbed 3 and a road floor in order from at least an upper part. The uppermost surface layer being the uppermost position is formed as a water retentive surface layer 7 by filling water retentive cement milk 11 for retraining water in a void of a pavement layer made in the predetermined thickness by an open-graded asphalt 9. The roadbed 3 positioned in the next place is formed as a water retentive roadbed layer 19 having a layer thicker than the surface layer 1 by using an aggregate 15 having an infinite number of small holes for retaining water, and a large quantity water is retained by a combination of the water retentive roadbed layer 7 and the water retentive roadbed layer 19. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a road pavement structure including a surface layer, a roadbed, and a roadbed.

  In general, asphalt pavement, when exposed to the sun, increases the road surface temperature due to direct sunlight, and particularly in summer, the effect is large and contributes to the heat island phenomenon.

  For this reason, in recent years we have already implemented water retention pavement that has a water retention function to accumulate rainwater etc. on the surface layer which is the surface of asphalt pavement, and lowers the road surface temperature with the heat of vaporization when the water is evaporated by solar heat. There is a place.

  Since the conventional water-retaining pavement that lowers the road surface temperature is only a thin surface layer, it is difficult to secure a large amount of water retention. For this reason, short days of road surface temperature decrease are a bottleneck, and it has been desired that the decrease in road surface temperature can be maintained over a long period.

  Accordingly, an object of the present invention is to provide a road pavement structure in which a large water retention capacity can be obtained without changing the structure of the surface layer, roadbed, and roadbed constituting the road.

  In order to achieve the above object, in the present invention, at least a surface layer, a roadbed, and a roadbed are formed in order from the top, and the uppermost surface layer, which is the uppermost layer, has a predetermined thickness by open-graded asphalt. A water-retaining cement milk that retains water is filled in the voids of the pavement layer made into a water-retaining surface layer, while the roadbed located next is an aggregate with countless small holes that retain water. The water-retaining roadbed layer is thicker than the surface layer.

  According to the present invention, the surface layer as a surface can be a water-retaining surface layer, and the roadbed below the surface layer can be a water-retaining roadbed layer, so that water can be retained over both the surface layer and the roadbed having a thicker layer than the surface layer. The road surface temperature can be lowered over a long period of time by retaining a large amount of water without using energy such as pipes and water tanks.

  On the other hand, since the roadbed supporting the surface layer uses aggregates as in the prior art, a roadbed layer having a predetermined thickness can be obtained without reducing the roadbed strength, and can be implemented without changing the road structure of the surface layer, roadbed, and roadbed.

  In the present invention, as a preferred embodiment according to the best mode, the surface layer serving as the water retention surface layer is provided with a water-permeable pavement region that allows rainwater or the like to pass toward the roadbed layer below the surface layer. Ensure that rainwater reaches the roadbed layer quickly and reliably through the permeable pavement area even when there are few.

  Hereinafter, the present invention will be described in detail with reference to FIGS.

  FIG. 1 shows a schematic cross-sectional view of a road pavement structure, which is a surface layer 1, a roadbed 3, and a roadbed 5 in order from the top.

  The surface layer 1 is formed as a water-retaining surface layer 7 that retains water, and a part of the surface layer 1 is a water-permeable pavement region d that allows rainwater or the like to permeate toward the lower roadbed 3.

  The water-retaining surface layer 7 is formed in a surface layer having many voids by an open-graded asphalt 9 serving as a paving material, and has a structure filled with water-retaining cement milk 11 that retains water in the voids.

The water-retaining cement milk 11 is made, for example, according to the blending ratio shown in Table-1.

  The super-fast hardening type in Table 1 uses a high-performance AE water reducing agent and water ratio slightly higher than the normal type and early strength type, and a setting retarder.

As a result, the P funnel flow value of the present invention is 9.5 (seconds), (conventional method half deflection performance: 12 seconds), and the maximum water absorption rate of the present invention is 43.8% (conventional method) : 12.5%), in the compressive strength of the present invention is 21N / mm ² (conventional method: property values thereof 20 N / mm ²⁾ is ensured.

  On the other hand, the water-permeable pavement region d formed on the surface layer 1 is a region in which the water-retaining cement milk 11 is not filled, so that rainwater or the like can quickly move from a large number of gaps e of the open-graded asphalt 9 toward the lower roadbed 3. It is supposed to flow through.

  The water-permeable pavement area | region d can be provided along both sides of the water retention surface layer 7, and the state seen from the plane is shown in FIG. As a result, in the case of a roadway, rainwater flows from the place where the central portion is high and inclined toward the left side toward the permeable pavement region d on both sides, so that water is efficiently collected.

  In this case, in the case of a sidewalk or the like, a rectangular water-permeable pavement region d that allows rainwater or the like to permeate over a predetermined area into a region formed in a recessed portion where rainwater or the like easily flows in a part of the water-retaining surface layer 7 as shown in FIG. May be provided randomly.

  The water-permeable pavement area d is a means for quickly flowing rainwater or the like toward the roadbed 3 below the surface layer 1, and as a modification thereof, for example, it fell on the left and right banks 13 as shown in FIG. 4. It is also possible to use a means in which rainwater is taken in from both of the roadbed 3 that becomes the water-retaining roadbed layer 7 through the ground.

  The roadbed 3 is thicker than the surface layer 1 by a combination of an aggregate 15 having innumerable small holes for retaining water and a gap 17 retained between the aggregate 15 and the aggregate 15. A roadbed 19 is made.

  In making the water-retaining roadbed 19, the use of the aggregate 15 having innumerable small holes is as described above, but the ratio of using this aggregate 15 is 50% or more when the total is 100. May desirably be 100%. In this case, the aggregate 15 has innumerable small holes, but does not have any adverse effect on the rigidity of the roadbed strength.

  The aggregate 15 having innumerable small holes is made of different materials as long as the strength of the roadbed is not reduced, in addition to using crushed materials obtained by crushing roof tiles, artificial sintered materials, bricks, various slags, volcanic rocks and shale. It is also possible to mix and use an appropriate amount of a water-absorbing synthetic resin material.

  The roadbed 5 is made of roadbed soil that is less permeable to water. As a result, water accumulates in the gaps 17 between the aggregate 15 and the aggregate 15 constituting the roadbed 3 on the road bed 5, so that the aggregate 15 and the aggregate in addition to the amount of water retained by the aggregate 15 itself. A large amount of water retention is ensured by a combination with the amount of water retained in the gap 17 between 15.

  In the road pavement structure configured as described above, the rain that has fallen on the road surface is retained in the water retaining surface layer 7 that is the surface layer 1 and is retained until saturated, and then flows to the lower road surface 3 and is retained by the water retaining surface layer 19. Is done. At this time, since rainwater also flows into the roadbed 3 from the water-permeable pavement region d provided on both sides of the surface layer 1, even when the amount of precipitation is small, the water is quickly retained by the water-retaining roadbed layer 19 that is slow to evaporate.

  On the other hand, the road surface temperature is reduced by the heat of vaporization evaporating from the water-retaining surface layer 7, and even if the water retention amount of the water-retaining surface layer 7 becomes zero, the aggregate 15 of the water-retaining roadbed layer 19 and the gap 17 between the aggregates 15 are aggregated. The road surface temperature can be lowered over a long period of time by the amount of water retained by the water retention of the 15 itself.

  On the other hand, since the roadbed 3 supporting the surface layer 1 uses the aggregate 15 as in the prior art, a roadbed layer having a predetermined thickness can be obtained without reducing the roadbed strength. This can be implemented without changing the structure of the road bed 5.

1 is a schematic sectional view showing a road pavement structure according to the present invention. The top view which showed a part of road pavement structure. The outline top view similar to FIG. 2 which showed another embodiment of the water-permeable pavement area | region. The outline cut sectional view showing the road pavement structure which showed another embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface layer 3 Roadbed 5 Roadbed 7 Water retention surface layer 9 Open grain asphalt 11 Water retention cement milk 15 Aggregate 17 Crevice 19 Water retention roadbed layer d Water-permeable pavement area

Claims (2)

  Water retention to keep water in the gap of the pavement layer that is composed of at least the surface layer, the roadbed, and the roadbed in order from the top, and the uppermost surface layer, which is the highest level, is made to a predetermined thickness by open grain asphalt The water-retaining surface layer is filled with water-soluble cement milk, while the next roadbed is made into a water-retaining roadbed layer that is thicker than the surface layer using aggregates with countless small holes for retaining water. Road pavement structure characterized by   The road pavement structure according to claim 1, further comprising a water-permeable pavement region that allows rainwater or the like to permeate toward a roadbed below the surface layer in the surface layer serving as the water retention surface layer.

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