JP3243631B2 - Pavement using artificial aggregate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resilient pavement having excellent antifreezing durability.

[0002]

2. Description of the Related Art In recent years, in snowy and cold regions, due to restrictions on the use of spiked tires, urgent measures are required to ensure smooth and safe vehicle traffic in winter. As a countermeasure from the pavement side, a method of lowering the freezing temperature by mixing an inorganic chloride-based material into the pavement, a particle size of 2.5 mm
A method of adding pulverized rubber particles to the asphalt mixture and kneading the same to impart elasticity to the pavement body to suppress freezing, or a method of completely exposing the road surface by road heating is used. However, in the method using chloride-based materials, the eluted chloride solution causes problems such as rusting of road structures and plant damage, and the durability of pavement remains after chloride elution. This is not a desirable method because there are cases where the voids have an adverse effect on durability, such as a decrease in wear resistance.

[0003] In the method of adding and kneading rubber particles, the addition amount is generally about 3 to 5%, but with such an addition amount, it is difficult to obtain high elasticity as a whole pavement. . Furthermore, the effect of local elasticity due to the rubber particles exposed on the surface also shows that the rubber particles are small in size and the exposed area is small, so that freezing such as destruction of frozen surfaces due to bending and adhesion to pavement is reduced. A sufficient effect on suppression cannot be expected. Actually, even in the application example on the actual road, a steady effect has not yet been confirmed. As a countermeasure, it is conceivable to increase the amount of added rubber particles, but even at the current amount of addition, it is difficult to tighten when compacted.
Due to concerns about durability such as wear and scattering of rubber particles, it is difficult to extremely increase the amount of addition. Therefore, although this method has no effect on environmental conservation, problems remain in terms of steady effects and durability. In road heating, the effect is extremely large due to the reliable exposure of the road surface, but the initial cost and running cost are high, and the widespread use of the road will reduce or increase road management costs in winter, so the application area will be large. No significant increase can be expected.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the conventional elastic pavement to which rubber particles are added, secure a steady road surface freezing suppression effect, and have good durability. To provide a resilient roadway pavement.

[0005]

Means for Solving the Problems The present invention exposes the aggregate-like elastic material having a particle size on the surface of the pavement is 10~30mm paving surface
The elasticity of press fitting so that the ratio of
The present invention relates to an antifreezing pavement having a pavement. In the present invention, as the material of the pavement for press-fitting the aggregate-like elastic body, asphalt-based , cement-based, resin-based, etc., as long as it is a material that can be finished by leveling and rolling, pouring work, essentially any type and Compounds may also be used. For example, rolled asphalt mixture, open grain asphalt mixture, crushed mastic mixture, goose asphalt mixture, semi-flexible pavement mixture , cement concrete
Etc. are raised. The detailed composition of these pavement materials is, for example, asphalt-based, by examining the durability, mixability, workability, etc. by marshall test, etc., and designed to suit the application and usage, but for other materials As with the asphalt system, the purpose is to use the conventional technology,
Formulation is designed according to the application.

The aggregate-like elastic material used in the present invention has a particle size of 10
３０30 mm, which is more elastic than the pavement, and includes natural or synthetic rubber, urethane-based resin, cork, or a composite thereof, and particularly those having heat resistance are preferably used. In addition, the elasticity and elasticity here refer to a large strain within the elastic limit like rubber, and are different from the elastic behavior of rigid bodies. When the degree of elasticity is represented by the hardness of rubber, it is generally in the range of JIS hardness of 50 or more at 20 ° C., although it varies depending on the material of the pavement and construction conditions. The shape of the elastic body is not particularly limited as long as it can be used as an aggregate . In order to obtain good durability by being completely press-fitted, it is usually desirable that the pavement material to be press-fitted be at least 粒径 of the aggregate maximum particle size and 舗 of the pavement thickness, particularly It is desirable that the ratio be 1 / 2.5 or less.
In addition, in order to obtain uniformity, a single particle size having a narrow particle size range is more desirable.

Further, when there is a concern that the elastic body may be scattered at places where traffic is extremely large, the base material may be coated on the elastic body in advance or applied or sprayed on the pavement surface. It is preferable to increase the adhesion of the material to the pavement material. Thereby, higher durability against scattering of the elastic body can be obtained. As the binder to be used, besides asphalt-based binders such as straight asphalt, emulsions and various resin binders such as epoxy-based and acrylic-based binders, any binders can be used as long as they improve the adhesion to the base material. In the case of coating, the amount used is generally 1 in weight ratio to the elastic body.
The optimum range varies depending on the type of the binder used. In the case of application or spraying, usually 0.3 to 1.5 kg / m ² per unit area
It is about.

Further, when the pavement is concerned about flow, or when coloring the pavement in a bus lane or landscape pavement, the temperature of the pavement is reduced by using a light-colored or colored elastic material to reduce the flow resistance. And the pavement surface can be variously colored. When constructing an elastic pavement by press-fitting an aggregate-like elastic material, first of all pavement materials, the materials are leveled by a normal construction method according to each pavement material. The press-fitting of the aggregate-like elastic body is, for example, in the case of a pavement compacted by compaction such as asphalt concrete, a predetermined amount of the aggregate-like elastic body is sprayed on the surface where the leveling has been completed, and becomes a base. Rolling is performed simultaneously with the pavement material to press-fit the aggregate-like elastic body.
The amount of spraying at this time varies depending on the weight of one elastic body to be used, but when the weight is 5 to 7 g / piece, it is ² to 8 kg / m ² , which prevents scattering due to the denseness of the elastic body. In order for the elastic body to have a particle size of 20
It is preferably 300 to 600 pieces / m ² in the case of about mm. In addition, by ensuring that the ratio of the press-fitted elastic body exposed to the pavement surface is 8% or more , remarkably excellent freezing suppression is achieved.
The effect is obtained.

[0009] In the pavement which is compacted by vibration like cement concrete, a predetermined amount of an elastic body is sprayed on the leveling surface, and then compacted with a vibrator at the same time as the pavement material serving as a base, and the elastic body is pressed into the pavement. I do. In addition, in the case of a pavement material that can be finished only by leveling by pouring work that does not require compaction work, after the artificial aggregate is sprayed on the leveling surface, for example, the elastic body is formed by a flat plate of appropriate size, etc. And press-fit. In the construction of an elastic pavement according to the method, even if the existing pavement becomes rigid after finishing, if the pavement is softened by reprocessing such as heating so that it can be press-fitted, It does not matter whether it is new or existing.

[0010]

[0011]

According to the elastic pavement according to the present invention, it is possible to improve all of the steady freeze suppressing effect and good durability, which were problems in the conventional freeze suppressing pavement utilizing elasticity. It is also possible to reduce the noise caused by running the vehicle. The mechanism for suppressing the road surface freezing of the elastic pavement can be explained as follows. First, the first factor is that the elasticity of the aggregate-like elastic material mixed in the pavement material increases the amount of deflection of the pavement during loading, and the critical strength of the ice plate (for example, allowable deflection and allowable stress). This is to promote cracking and peeling of the ice plate by reducing the strength or reducing the strength. The second factor is that the deformation and the stress of the ice plate are increased by local deformation of the aggregate-like elastic body exposed on the road surface at the time of loading, and the same effect as described above is obtained. The third factor is that the adhesion of ice to rubber or urethane resin used as an aggregate-like elastic body is generally small, so that the adhesion of the part where the elastic body is exposed to the road surface is reduced, and Peeling is promoted.

Therefore, the effect of suppressing freezing is improved by increasing the deflection of the entire pavement and increasing the number of elastic bodies exposed on the surface. This means that in the conventional method, the amount of added rubber particles is increased. However, in a pavement constructed by compaction, an extreme increase in rubber particles does not provide a sufficient compaction effect due to the elasticity of rubber at the time of compaction, resulting in a dense pavement, resulting in a significant decrease in strength and durability. I do. Particularly when the diameter of the rubber particles is small, scattering of the rubber particles becomes a problem after the operation. Further, even when the added amount of the rubber particles is increased, the local deformation is small because the particle size of the rubber particles is small, and the effect of reducing the adhesive force cannot be expected because the amount of exposure to the surface is limited. . Therefore,
Disadvantages of the conventional elastic pavement result from the inability to obtain a sufficient compaction effect and the small rubber particle size.

In the elastic pavement of the present invention in which the aggregate elastic body is press-fitted, the effect of the elasticity of the aggregate elastic body on compaction during rolling is limited to the vicinity of the surface, and the aggregate elastic body is compacted. Because the surface is scattered on the surface, the compacting effect is hardly impaired, and sufficient strength and durability can be secured. Further, in the pavement, the entire pavement cannot be increased in deflection, but since the particle size of the aggregated elastic body to be press-fitted is larger than in the past, local deformation is large, and the range of influence is widened. Furthermore, even when the amount of application is relatively small, the ratio of the area where the aggregate-like elastic body is exposed to the surface is large, so that the adhesion of the ice plate can be sufficiently reduced.

[0014]

Further, the elastic pavement according to the present invention has not only the effect of suppressing freezing but also the effect of reducing traffic noise due to the running of the vehicle and suppressing the freezing of the road. The occurrence of traffic noise depends on various factors, and a major factor among them is noise generated from tires, so-called tire noise. Generation of tire noise is caused by release of air compressed in the tire tread, vibration of the tire side surface, and the like. However, in the elastic pavement according to the present invention, the impact due to the unevenness of the road surface when the tire is in contact with the ground is mitigated by the elasticity of the aggregate-like elastic body exposed on the entire pavement or on the surface. Vibration is small, and generation of tire noise during running can be suppressed. During frost heaving on the road, the temperature inside the pavement decreases due to cooling by the outside air during the cold season, and the water in the subgrade or subbase increases in volume due to icing, resulting in destruction of the pavement and reduction in strength. It is generally known that rubber, urethane resin, cork, and the like, which are commonly used materials for the aggregate-like elastic body, have low thermal conductivity. By spraying or mixing a predetermined amount of the elastic material, the layer functions as a heat insulating layer, which suppresses the release of heat inside the pavement during the cold season, and is also effective in suppressing frost heave on the roadbed and the roadbed.
Therefore, the elastic pavement in which the aggregate-like elastic body according to the present invention is press-fitted and mixed therein eliminates the drawbacks of the conventional elastic pavement, provides a steady freezing suppression effect and a good durability, and furthermore has a good traffic performance. It is also possible to provide noise reduction and road frost heave suppression effects.

[0016]

The following is an example in which samples of a conventional elastic pavement and an elastic pavement according to the present invention were prepared, and their freezing suppression effect and durability were compared in a laboratory test.

Example 1 A conventional elastic pavement is a mixture (A) obtained by adding 5% of rubber particles having a particle size of 2.5 to 5 mm to the weight of the mixture to an asphalt mixture having a gap type particle size. Were prepared as mixtures (B) with the addition amount of 9%. Table 1 shows the composition of the mixture.

The elastic pavement according to the present invention is a mixture (C) obtained by spraying 4 kg / m ^{2 of an} elastic rubber material having a particle diameter of 13 mm onto the surface of a mixture for rolled asphalt and press-fitting the mixture. A mixture obtained by mixing the same aggregate-like elastic body with the mixture at 10% with respect to the weight of the mixture was prepared as a mixture (D). Table 1 shows the composition of the mixture. The test specimens used in the test were the above four types, and the tests were performed by a labeling test and an ice plate destruction test, respectively, to compare the durability and the freeze suppression effect. In the labeling test, a test piece having a width of 15 cm, a length of 45 cm, and a thickness of 5 cm was used. The test conditions were a temperature of −10 ° C., a test time of 90 minutes, and a wear amount measured using a cross chain.

The ice plate breaking test was performed in the following manner. The specimen was 30 cm in width and length and 5 cm in thickness. A 3 mm-high mold was provided around the mold, and water filled in the mold was frozen to form a 3 mm-thick ice plate. Next, traverse running of a wheel tracking test (load: 70 kg) was performed in a room at a room temperature of −5 ° C. by using the test pieces from which the molds were removed, and the number of running times at which the ice plate of each test piece was cracked was measured. . The test results are as shown in Table-2.

After the test of the mixture (A) in the labeling test, the state of the test piece was such that rubber particles were scattered together with the mortar on the surface and grooves were formed due to wear. The amount of abrasion of the mixture (B) in the labeling test was extremely large as compared with that of the mixture (A), and the state of the specimen after the test was partially broken due to abrasion. this is,
This is because the specimen of the mixture (B) was not compacted at all, indicating that it was impossible to use the mixture on a real road.
On the other hand, the specimens of the mixture (C) and the mixture (D) were very small in comparison with the amount of wear of the mixture (A). It was not worn. According to the results of the ice plate destruction test, the mixture (A) and the mixture (B) showed no ice plate cracking even after 100,000 runs corresponding to the number of running wheels in a heavy traffic route for about one month, and the ice plate was prevented from freezing. No effect could be confirmed. Further, for the mixture (C) and the mixture (D), although there is a slight difference in the number of running times at which the ice plate cracks, both of them are first exposed to the aggregate-like elastic body exposed on the surface. Cracking occurred, and the range tended to expand as the number of runs increased, and a favorable freezing suppression effect was observed. Therefore, the pavement according to the present invention has excellent resistance to abrasion as compared with the conventional pavement, and also has a very good freezing suppressing effect.

[0021]

[Table 1]

[0022]

[Table 2]

Example 2 The following is an example of comparative analysis using the finite element method with respect to the rate at which the press-fitted elastic body is exposed on the pavement surface and the destruction effect of the ice plate. Fig. 2 shows the results of a comparison of the state of tensile stress generated in the ice plate layer when the ice plate formed on the surface of the elastic pavement is loaded using the finite element method while changing the surface exposure rate of the elastic aggregate. is there. The analysis conditions are as follows. The analysis model is a two-dimensional four-node solid element, and the position of the model end is set according to the surface exposure rate. Other conditions are as shown in Table 3 and FIG. Note that the model end is the farthest part of the area covered by each elastic body. According to this result, when the exposure rate is 10 to 15%, the tensile stress is 10 to 20 kgf / cm.
The stress state of ² reaches the model end. Generally, the ice plate has a tensile breaking strength of about 15 kgf / cm ² , and this state suggests that the ice plate breaks over the entire loading area. Therefore, in order to obtain a sufficient freezing suppression effect, it is desirable to secure a road surface exposure rate of 8% or more, particularly about 10%.

Example 3 An example is shown below in which specimens of ordinary pavement and an elastic pavement according to the present invention were prepared, and their heat insulating effects were compared in a laboratory test. The ordinary pavement is a pavement (A) in which only the mixture for rolled asphalt is used as the surface layer mixture, and the elastic pavement according to the present invention has a particle size of 20 on the surface of the mixture for rolled asphalt.
3 kg / m ² , 6 kg / m ²
Specimens each having a width and a length of 30 cm were prepared as pavements (B) and (C) which were sprayed and press-fitted. The cross-sectional configuration of each pavement is as follows: surface layer 5 cm, base layer 5 cm, roadbed layer 5 c
m, and the base layer and the roadbed layer were each made of a general material such as a coarse-grained asphalt mixture and granular crushed stone. In the test, the above three types of specimens were left in a constant temperature room, and the room temperature was changed from 20 ° C to -20 ° C, and the temperature change on the lower surface of the roadbed layer was measured using a thermocouple. FIG. 3 shows a comparison result of the measured temperature change of the lower surface of the roadbed layer. The change in outside air temperature and the section of the pavement are as shown in the figure. The minimum temperature of the pavements (B) and (C) is higher than that of the pavement (A) by about 2 ° C. to 4 ° C., and the time during which the temperature is 0 ° C. or less is short. In the pavements (B) and (C), the minimum temperature is higher in the pavement (C) in which the amount of the press-fitted aggregate-like rubber elastic body is larger,
The time below 0 ° C is also short. That is, this difference is the difference in the amount of the aggregated rubber elastic body used as the heat insulating material. The larger the amount of the spray, the better the heat insulating effect. By the way, in the suburbs of Sapporo, Hokkaido, the temperature of the underside of the roadbed at a depth of 30 cm from the pavement surface in winter was measured, and the lowest temperature was -3 ° C to -4 ° C. It is possible to suppress the frost heave of the floor and the roadbed. Therefore, the pavement according to the present invention has the effect of suppressing the frost heave of the roadbed and the roadbed.

Table 3 Spraying amount Maximum edge distance Tensile stress: Tensile stress: Tensile stress: 10 kg / cm ² 15 kg / cm ² 20 kg / cm ² 5.5 28.5 18 16 14 6.2 25.5 7.7 25.5 819 16.3 14.2 9.2 23.5 9.8 22 17.5 14.6 10.8 21.55 12 20.2 12.3 20.2 12.6 16 13.8 19.05 14.6 18 15.4 18.05 16.9 17.2 18.5 16.45

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a conventional mixture and a mixture of the present invention.

FIG. 2 is a graph showing an analysis result on a surface exposure rate of an elastic aggregate and a breaking effect of an ice plate.

FIG. 3 is a graph showing a temperature measurement result of a lower surface of a roadbed layer.

[Explanation of symbols] a: crushed stone b: asphalt mortar c: rubber particles d: elastic artificial aggregate e: asphalt coating

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akio Taniguchi 1-19-11 Kyobashi, Chuo-ku, Tokyo Japan Pudo Co., Ltd. (72) Inventor Toru Abe 1-19-11 Kyobashi, Chuo-ku, Tokyo Japan pavement Inside the Company (72) Inventor Yuki Morikawa 1-19-11 Kyobashi, Chuo-ku, Tokyo Inside the Japan Road Company (56) References JP-A-6-272205 (JP, A) JP-A-6-279684 (JP) , A) JP-A-4-140301 (JP, A) JP-A-5-106204 (JP, A) JP-A-6-280211 (JP, A) Japanese Utility Model No. 5-54604 (JP, U) Japanese Utility Model Application 63-65703 (JP, U) JP 43-4696 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) E01C 11/24 E01C 7/35 E01C 7/02-7 / 18 E01C 7/26-7/30

Claims (8)

(57) [Claims] 1. A ratio of exposing an aggregate-like elastic body having a particle size of 10 to 30 mm to the surface of a pavement made of an asphalt-based or cement-based pavement material is 8% or more.
Freezing pavement formed by press-fitting
Body . 2. A pavement material into which the particle size of the aggregate-like elastic body is press-fitted.
骨 of the maximum particle size of the aggregate and の of the pavement thickness
The pavement according to claim 1, which is: 3. An aggregate-like elastic body to be press-fitted has a JIS hardness of 50.
The pavement according to claim 1 or 2, which is as described above . 4. An aggregate-like elastic body to be press-fitted is formed by a binder.
The method according to any one of claims 1 to 3, wherein
Pavement. 5. The mixture for press-fitting an aggregate-like elastic body is a roll.
A mixture as claimed in any one of claims 1 to 4, which is a door asphalt mixture.
The pavement according to the item . 6. The mixture for press-fitting an aggregate-like elastic material has an open particle size.
It is an asphalt mixture, The any one of Claims 1-4.
The pavement as described . 7. A crushed stone mixture for press-fitting an aggregate-like elastic body .
5. A stick mixture according to any one of claims 1 to 4.
Pavement. 8. The mixture for press-fitting an aggregate-like elastic body is a goose.
It is an asphalt mixture, The any one of Claims 1-4.
The pavement as described.