JP4952082B2 - Freezing control paving material - Google Patents

Description

  The present invention relates to a freeze-inhibited pavement, and more particularly to a freeze-inhibited pavement capable of obtaining an excellent anti-freeze effect over a long period of time.

  Conventionally, anti-freezing pavement materials that prevent frozen road surfaces such as ice burns and mirror burns are known (see, for example, Patent Document 1). These anti-freezing pavement materials are generally composed of a mixed material obtained by mixing a hard aggregate such as sand and an elastic aggregate such as a rubber chip and a resin binder. With this configuration, the elastic aggregate causes local elastic deformation of the anti-freezing pavement due to the load of the traveling vehicle, and the ice on the surface is crushed by this elastic deformation to suppress freezing.

However, there is a problem that the freeze suppression pavement is repeatedly subjected to a load from the traveling vehicle, so that hard aggregates and elastic aggregates are broken over time, and cracks are generated due to lack of flexibility. Therefore, it is difficult to maintain the initial freezing suppression effect for a long period of time, and a freezing suppression pavement that can maintain the effect for a long period of time has been demanded.
JP-A-9-165248

  An object of the present invention is to provide a freeze-inhibited pavement that can exhibit an excellent anti-freeze effect over a long period of time.

In order to achieve the above object, the anti-freezing paving material of the present invention is a anti-freezing paving material composed of a mixed material containing hard aggregate, elastic aggregate and resin binder, and the particle size of the hard aggregate is 0.00. 4 mm or more and 2.4 mm or less, and the elastic aggregate is composed of at least two kinds of powdered rubber having a particle size of 0.5 mm or less and granular rubber having a particle size of 2.8 mm or more and 10.0 mm or less . The average particle diameter is 0.2 mm or more and 0.4 mm or less, the average particle diameter of the granular rubber is 4.0 mm or more and 6.0 mm or less, and the elastic aggregate with respect to the total volume of the hard aggregate and the elastic aggregate The volume ratio of the mixture is 18% or more and 50% or less, and the volume ratio of the powdered rubber to the volume of the elastic aggregate is 4.2% or more and 75% or less, and the porosity of the mixed material is 20% or more and 30% or less. characterized in that it is That.

  According to the anti-freezing pavement of the present invention, the particle size of hard aggregates and elastic aggregates as constituent elements is regulated within an appropriate range, and the elastic aggregates are powdered rubber and particles having a particle diameter of 0.5 mm or less. Two types of granular rubber having a diameter of 2.8 mm to 10.0 mm are included, and the volume ratio of the elastic aggregate to the total volume of the hard aggregate and the elastic aggregate is 18% to 50%, and the volume of the elastic aggregate By regulating the volume ratio of powdered rubber to 4.2% or more and 75% or less, the resin binder solidifies the aggregates uniformly and suppresses the deagglomeration of the hard and elastic aggregates. In addition to ensuring sufficient flexibility and sufficient elastic deformation to break ice on the pavement surface, it is possible to obtain a certain level of anti-slip effect when wet. As a result, it is possible to maintain an excellent anti-freezing effect over a long period of time.

Hereinafter, the anti-freezing paving material of the present invention will be described based on the embodiments shown in the drawings.
As illustrated in FIG. 1, the antifreezing pavement material 1 of the present invention is composed of a mixed material including a hard aggregate 2, an elastic aggregate 3, and a resin binder 4, and has an appropriate gap 5. Moreover, carbon black (not shown) is mixed in the resin binder 4 for the main purpose of coloring the antifreezing pavement material 1.

  Examples of the resin binder 4 include moisture-curing one-component polyurethane resin, two-component polyurethane resin, epoxy resin, and polyester resin. The resin binder 4 is blended in a proportion so that the surfaces of the hard aggregate 2 and the elastic aggregate 3 can be covered with a certain film thickness, and carbon black is blended at a certain ratio with respect to the blend amount of the resin binder 4. Is done.

  The resin binder 4 covers the surfaces of the hard aggregate 2 and the elastic aggregate 3 with a substantially uniform film thickness, and the hard aggregate 2 and the elastic aggregate 3 are consolidated together. Carbon black can be omitted if not necessary.

The hard aggregate 2 has a great influence on the anti-slip effect when wet in the anti-freezing paving material 1, and examples thereof include quartz sand, natural stone, artificial stone, and resin-based chips. The particle size is 2.4 mm or less in order to make it difficult to remove particles. The lower limit of the particle size is the lower limit of the hard aggregate 2 that is generally used, and is 0.4 mm in order to ensure a certain level of drainage .

  The elastic aggregate 3 includes two types of elastic aggregates 3, a powdered rubber 3 a having a particle size of 0.5 mm or less and a granular rubber 3 b called a so-called rubber chip having a particle size of 2.8 mm to 10.0 mm. ing. When the particle size distribution of the elastic aggregate 3 is schematically shown with respect to the entire volume of the hard aggregate 2 and the elastic aggregate 3, as shown in FIG. 2, two particle size regions corresponding to the powder rubber 3a and the granular rubber 3b are obtained. The distribution has a peak.

  In the present invention, the hard aggregate 2 and the elastic aggregate 3 are mixed by mixing the two types of elastic aggregates 3 of the powdery rubber 3a and the granular rubber 3b so that the particle size distribution has two peaks. However, the gaps 5 are provided through the resin binder 4 and can be uniformly bonded and firmly consolidated. Therefore, it is difficult for the hard aggregate 2 and the elastic aggregate 3 to be broken for a long time.

  The elastic aggregate 3 greatly affects the flexibility in the anti-freezing pavement 1. Therefore, in order to sufficiently exhibit this flexibility, in the present invention, the volume ratio of the elastic aggregate 3 to the total volume of the hard aggregate 2 and the elastic aggregate 3 is set to 18% or more and 50% or less. If the volume ratio of the elastic aggregate 3 is less than 18%, sufficient flexibility cannot be obtained, and if it exceeds 50%, the freezing suppression pavement material 1 has a large sag due to repeated loading by the traveling vehicle. Wrinkles occur and sufficient durability cannot be obtained.

  Among the elastic aggregates 3, the powdered rubber 3 a greatly contributes to prevention of cracking of the anti-freezing pavement 1, and the granular rubber 3 b greatly increases the local elastic deformation due to the load of the traveling vehicle of the anti-freezing pavement 1. Contribute. Therefore, in the present invention, the volume ratio of the powdered rubber 3a with respect to the total volume of the elastic aggregate 3 is regulated to 4.2% or more and 75% or less, and the anti-cracking pavement material 1 is prevented from cracking and freezing-suppressing effect. To make it compatible.

  The reason why the volume ratio of the powdered rubber 3a is set to 4.2% or more is to obtain a sufficient crack prevention effect, and the volume ratio is set to 75% or less for the anti-freezing paving material 1. This is to prevent the sagging and not lower the durability. Along with the volume ratio of the powder rubber 3a, the volume ratio of the granular rubber 3b also becomes appropriate, and the granular rubber 3b causes local elastic deformation due to the load of the traveling vehicle, and the ice that freezes on the anti-freezing pavement material 1 Destroy.

  At this time, elastic deformation due to the powdered rubber 3a also occurs, so that an excellent antifreezing effect is exhibited by the cooperation of the granular rubber 3b and the powdered rubber 3a. Further, as described above, since the hard aggregate 2 and the elastic aggregate 3 are uniformly and firmly consolidated to prevent grain removal, this excellent anti-freezing effect can be maintained over a long period of time.

Powdery rubber 3a, the average particle size of the particulate rubber. 3b, below 0.4mm respectively 0.2mm or more so-called median diameter, and is 4.0mm or more 6.0mm or less, in particular powdery rubber 3a is 0.3mm approximately, By setting the granular rubber 3b to about 5.0 mm, a more uniform and stable effect can be obtained.

  The elastic aggregate 3 may be of two types, the powdered rubber 3a and the granular rubber 3b, but there is a small amount of rubber material having other particle sizes not exceeding the respective volume ratios of the powdered rubber 3a and the granular rubber 3b. May be. These powdery rubber 3a and granular rubber 3b can be produced, for example, using a used tire as a raw material.

  Moreover, since the porosity of the mixed material which comprises the freeze suppression pavement material 1 can be excellent in durability with the outstanding drainage property by making it into 20% or more and 30% or less, it is preferable. When the porosity is less than 20%, the drainage performance is lowered, and the slip prevention effect when wet is reduced. On the other hand, if the porosity is more than 30%, a large sag or wrinkle is likely to occur due to repeated loads by the traveling vehicle, which causes a decrease in durability.

  This anti-freezing pavement material 1 may be prepared by placing the above-mentioned mixed material in a formwork at a factory or the like and forming it into a panel body having a predetermined shape such as a quadrangle, and laying the panel body at a construction site. It is also possible to manufacture the above-mentioned mixed material by performing work, and lay this mixed material directly on the road surface as a base.

  The anti-freezing paving material 1 is not limited to the configuration shown in the above embodiment, and other materials can be mixed as necessary. For example, a plasticizer may be blended in advance in the elastic aggregate 3 to ensure further flexibility at low temperatures. Moreover, the hard aggregate 2 can be surface-treated using a solvent containing a silane coupling agent to increase the adhesive strength of the hard aggregate 2 and make it difficult to cause graining. The elastic aggregate 3 can be further prevented from graining by subjecting it to a surface treatment for increasing the adhesive strength using a solvent, a halogen compound-containing solution, an organic acid, an inorganic acid, or the like.

  Hard aggregate is No. 2 silica sand (particle size range 0.43 to 2.40 mm, average particle size (median diameter) 1.52 mm), and elastic aggregate is powder rubber (particle size range 0.5 mm or less, average particle size) Diameter (median diameter) 0.32 mm) and granular rubber (particle size range 2.8 to 10.0 mm, average particle diameter (median diameter) 5.1 mm). These aggregates, urethane resin binder and carbon black are represented. 15 types of test samples (Examples 1 to 10 and Comparative Examples 1 to 5) were prepared using the mixed material mixed in the volume blend shown in FIG. The following evaluation tests were conducted for each test sample, and the results are shown in Table 1. In the case of all the evaluation items, the case of ◯ was evaluated as ◯ in the comprehensive evaluation, and the others were indicated as ×.

[Ice wear strength]
It is a test method based on the so-called Kenken-type tensile test, and as shown in FIG. 3, each test sample 6 (cubic 6 cm in length, 11 cm in width, 3 cm in thickness) is fixed on the semi-flexible pavement material 7, A non-woven fabric 8 having a thickness of 5 mm is bonded in advance to the lower surface of the pulling jig 9, this non-woven fabric is immersed in water and placed on the upper surface of the test sample 6, and left at minus 5 ° C. for 4 hours to test sample 6 Freeze. Thereafter, the pulling jig 9 was pulled up vertically, the load when the nonwoven fabric 8 was peeled off from the test sample 6 was measured, and this load was defined as the ice adhesion strength D. A smaller value of the ice adhesion strength D indicates that the ice is more likely to break and the test sample 6 has a better anti-freezing effect. A case where the ice adhesion strength D is less than 0.4 MPa is indicated by ◯ in Table 1 as being excellent in the effect of suppressing freezing, and a case other than that is indicated by ×.

[Wet sliding friction coefficient]
The wet sliding friction coefficient μ during running at 60 km / h was measured by a so-called DFT (dynamic friction tester) test method based on ASTM E1911-98 (2002) in which a specified rubber piece circulates on each test sample. The case where the value of μ is 0.33 or more is indicated by ○ in Table 1 as being excellent in the slip prevention effect when wet, and the case other than that is indicated by ×.

[durability]
Track and bus tires (tread width: 225 mm) circulate on a road with a wheel load of 2100 kg and a traveling speed of 12 km / h on a road with a radius of 3 m on the road where each test sample was laid. The condition was observed. Cases where there is no surface cracking, aggregate grain removal, wrinkle generation, or mild and can be used sufficiently as roads are marked with a circle in Table 1, and cannot be used as roads as they are and need repair Is indicated by x.

  From the results of Table 1, the particle size of the hard aggregate and the elastic aggregate, the volume ratio A of the elastic aggregate with respect to the total volume of the hard aggregate and the elastic aggregate, and the volume ratio B of the powdered rubber with respect to the volume of the elastic aggregate It was confirmed that the antifreezing effect, the anti-slip effect when wet, and the durability were all in a favorable level by using the range defined in the present invention.

It is a schematic diagram which illustrates the freezing suppression paving material of this invention. 1 is a graph illustrating the particle size distribution of the elastic aggregate of the anti-freezing pavement. It is explanatory drawing which shows the measuring method of the ice adhesion strength of a test sample.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Freezing suppression pavement material 2 Hard aggregate 3 Elastic aggregate 3a Powdered rubber 3b Granular rubber 4 Resin binder 5 Cavity 6 Test sample 7 Base (semi-flexible pavement)
8 Nonwoven fabric 9 Pulling jig

Claims (3)

In the anti-freezing pavement composed of a mixed material including a hard aggregate, an elastic aggregate, and a resin binder, the hard aggregate has a particle size of 0.4 mm or greater and 2.4 mm or less, and the elastic aggregate is a granule It consists of at least two types of powdered rubber having a diameter of 0.5 mm or less and granular rubber having a particle size of 2.8 mm to 10.0 mm, and the average particle size of the powdered rubber is 0.2 mm to 0.4 mm, The average particle diameter of the granular rubber is 4.0 mm or more and 6.0 mm or less, and the volume ratio of the elastic aggregate to the total volume of the hard aggregate and the elastic aggregate is 18% or more and 50% or less, and the elastic bone A freeze-inhibited pavement in which the volume ratio of the powdered rubber to the volume of the material is 4.2% to 75% and the porosity of the mixed material is 20% to 30% . The antifreezing pavement according to claim 1, wherein the resin binder covers surfaces of the hard aggregate and the elastic aggregate with a substantially uniform film thickness . The antifreezing pavement according to claim 1 or 2 , wherein a plasticizer is blended in advance in the elastic aggregate, and the hard aggregate is surface-treated using a solvent containing a silane coupling agent .

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