JP2008291486A - All-weather elastic pavement repaired body and method of repairing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an all-weather elastic pavement repaired body formed by repairing, at low cost, an existing all-weather elastic pavement body deteriorated with time into a pavement body with excellent traveling feeling according to the standard values of the International Amateur Athletic Federation (IAAF) and a method of repairing the all-weather elastic pavement body. <P>SOLUTION: An existing all-weather elastic pavement body is cut out by a predetermined thickness 2-4 mm from the surface. A large number of core holes 7 are formed in the cutout surface 6 at predetermined intervals by using a drill. When the core holes are formed, its volume ratio is 16-54 capacity%. Next, the core holes 7 are filled with a low foam denaturation polyurethane resin 8 with a foam factor of 1.40-1.55. Also, a surface layer with a thickness according to the cutout thickness is formed on the polyurethane resin by using a 100% polyurethane resin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  This invention is a refurbishment of an all-weather elastic pavement made of a polymer elastic body such as polyurethane resin, which is often used for track, outdoor sports courts, jogging courses, walking paths, etc., using an overlay method. It relates to the improvement of the body and its repair method.

  The surface layer of an all-weather elastic pavement such as a track in an athletic stadium is usually made of a polymer elastic body such as polyurethane resin. In addition, the “hardness” of the pavement has standards by the International Federation of Athletics Federations (IAAF), the impact reduction rate (Force Reduction) is 35-50%, and the vertical displacement (Vertical Deformation) is 0.6- The tensile strength (Tensile Strength) is regulated to 0.5 MPa or more, respectively, to 2.5 mm. However, in track and field stadiums, even if they meet the above requirements immediately after pavement construction, they will not be able to meet the specified values over the years. In this repair, there is no problem if the paving body is completely re-paved and repaired. However, this method is generally partially repaired because the construction cost increases.

The present inventor has already proposed an invention for such a modification (Japanese Patent Laid-Open No. 2005-99717). This invention intends to renovate an existing all-weather elastic pavement, such as an athletic stadium, so that it conforms to the IAAF standard at a low cost, and the surface layer of the existing pavement surface is first fixed. The thickness is cut off, a number of grooves are formed on the scraped surface, and the foam is filled with a low foam modified polyurethane resin. After the resin is cured, the polyurethane resin is applied to the upper surface of the new paving as much as the shaved thickness. (See Patent Document 1).
Japanese Patent Laying-Open No. 2005-99717

  However, in the above-mentioned proposed invention, the existing pavement deteriorated over time can be repaired at low cost so as to conform to the IAAF standard. A new problem of receiving a different “running feel” appeared. This is because the above-mentioned renovation method employs a directional method called `` grooving '', and the runner is likely to shake laterally with respect to the groove formation direction. You will receive a “running feeling” and a different “running feeling” depending on the direction difference between the running direction and the groove direction.

  In view of such a point, the present invention, when renovating, not only adapts the pavement after refurbishment to the IAAF standard, but does not receive "side-shake" or "directionality" during traveling. It is to provide an all-weather elastic pavement repair body. Another object of the present invention is to provide a repair method that can make such a repair body easily and at low cost.

  The technical means of the all-weather elastic pavement repair body of the present invention is that the existing all-weather elastic pavement is scraped from the surface with a uniform thickness, and there are many core holes on the scraped surface so that the volume ratio is 16 to 54% by volume. The core hole is filled with a filler made of polyurethane resin, and a surface layer is formed on the core hole with polyurethane resin.

  Moreover, it is preferable that the filler is a low-foamed modified polyurethane resin having an expansion ratio of 1.40 to 1.55. Furthermore, the core hole may be cylindrical. The core hole may be arcuate.

  The method of repairing an all-weather elastic pavement according to the present invention is to cut the surface of an existing all-weather elastic pavement with a uniform thickness, and to form a large number of core holes on the scraped surface so that the volume ratio is 16 to 54% by volume, The core hole is filled with a filler made of polyurethane resin, and a surface layer is formed thereon with polyurethane resin.

  The all-weather elastic pavement repair body of the present invention can be remodeled with a high impact attenuation rate and a low vertical displacement amount, as well as stably conforming to standard values such as impact attenuation rate and vertical displacement amount stipulated by IAAF. In addition, construction is possible at a low cost, and there is no “side-off”, and the running feeling given to the runner is excellent.

  According to the second aspect of the present invention, since the low foaming modified polyurethane resin having a foaming ratio of 1.40 to 1.55 is used as the filler, it can be appropriately adapted to the IAAF standard value.

  According to the third aspect, since the core hole is cylindrical, it is possible to easily form the core hole by a drill or the like, and it is possible to completely eliminate the occurrence of vertical and horizontal directions on the paved surface after the repair. Can make an excellent ground.

  According to the fourth aspect of the present invention, since the core hole is arcuate, the core hole can be formed by a disc-shaped cutting cutter, and the construction is simple and can be performed at low cost.

  The all-weather elastic pavement repairing method of the present invention can repair a deteriorated pavement to the excellent pavement as described above easily and at low cost. Moreover, since construction is easy, it can be easily performed anywhere.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out an all-weather elastic pavement repair body and its repair method according to the present invention will be described below based on embodiments of the drawings. FIG. 1 shows the repair method of the present invention step by step. 1 in FIG. 1 is an example of an existing ground to be repaired, and 1 is a base layer. On the roadbed crushed stone layer, two asphalt layers of coarse particles and dense particles are placed. It is configured. On this base layer 1, an elastic surface layer 2 is paved with a thickness of about 13 mm. The surface layer 2 is composed of an elastic layer 3 at the lowest layer and a thickness of about 8 mm, and an EVA resin foam (an ethylene vinyl acetate resin foam having a specific gravity) as an elastic foam aggregate in a polyurethane resin. 0.35 and a particle size of 1.2 to 3 mm) is mixed by about 10% by weight. The upper layer of the elastic layer 3 is the overcoat durable layer 4, which is 100% polyurethane resin and has a thickness of 2 mm. A surface embossed finish layer 5 (thickness 1 mm) is formed on the durable layer 4. Note that the configurations of the base layer 1 and the surface layer 2 are various in the case of an existing ground. However, any configuration is subject to modification according to the present invention.

  1 shows a state in which the surface of an existing pavement is scraped off at a constant thickness, and a core hole 7 is formed at an appropriate position on the scraped surface 6. The scraped thickness is suitably 1 to 3 mm. For this scraping, a belt sander, a cutting machine, a scraper or the like is usually used to scrape the pavement layer from the surface with a certain thickness. Moreover, the diameter of the core hole 7 is usually 5 to 20 mm, the depth is 5 to 20 mm, and the formation pitch is 10 to 30 mm. The core hole 7 is formed using a drill or a punch. When the core hole 7 is formed, the volume ratio of the core hole 7 to the polyurethane pavement after shaving is set to 16 to 54% (according to the test described later) in order to keep the shock attenuation rate stable. . Moreover, the shape of the core hole 7 is free, such as a columnar shape, a key shape, an elliptical column shape, or a conical shape.

  The core hole 7 is filled with a filler 8 made of a low foaming modified polyurethane resin and / or a polyurethane resin blended with foamed aggregate. Low foaming modified polyurethane resin is a two-component room temperature curing polyurethane resin used for ordinary all-weather elastic pavement. By adding a foam stabilizer and stirring, fine closed cells are generated in the resin. Of 1.40 to 1.55. In addition, for the preparation of low foaming of this polyurethane resin, a so-called mechaflo method (Mechanical Forth Method) is applied, and as the foam stabilizer used therefor, organosiloxanes such as silicone oil, silicone resin, silicone modified resin, etc. Suitable compounds are polydimethylsiloxane, polyalkylene oxide adducts, vinyl silanes, polyoxyalkylene polyol compounds, and the like. This foam stabilizer is added in an amount of 1.0 to 2.0% by weight with respect to the polyurethane resin, and is made into a low foam modified polyurethane resin while mixing air by adjusting the rotation speed of a mixer equipped with a whisk. This is because a large number of fine closed cells are uniformly present in the polyurethane resin material, and it is appropriate to use a low foam having an expansion ratio of about 1.40 to 1.55. In the case of a polyurethane resin having a specific gravity of 1.25 used in the examples, the specific gravity after foaming is 0.81 to 0.89. In addition, when the expansion ratio of the low foam modified polyurethane resin is 1.55 or more, the tensile strength after curing is lowered and the standard value is not satisfied. Moreover, as foamed aggregate used together, for example, EVA (ethylene vinyl acetate) having a particle size of 0.5 to 2.0 mm is added to the polyurethane resin in an amount of 2.0 to 15.0% by weight. Is preferred. In addition, instead of the low foam modified polyurethane resin, a rubber chip capable of improving the impact attenuation rate or other foam aggregate may be filled.

  An appropriate volume ratio in forming the core hole 7 was tested. That is, the surface of the pavement is scraped to a thickness of 3 mm, a core hole having a diameter of 10 mm and a depth of 10 mm is drilled with an electric drill, and a test body is made by changing the pitch of the core hole from 10 to 24, and the IAAF impact attenuation rate And the improvement situation with the IAAF vertical displacement amount was measured to test what volume ratio is appropriate. The core hole was filled with a low foam modified polyurethane resin having an expansion ratio of 1.55, and a 2 mm thick topcoat durable layer and a 1 mm thick embossed finish layer were formed on the top surface. The test results are shown in Table 1. From this test, the impact attenuation rate improves as the core hole volume increases, and the vertical displacement is inferior to the normal overlay repair method when the volume ratio is less than 15.9%, and 54.1%. It has been found that when the value exceeds, it increases extremely. As a result, it has been found that the volume ratio at the time of forming the core hole is suitably 16 to 54%.

  Moreover, the verification test was done about the specific gravity of the low foaming modified polyurethane resin with which the core hole 7 is filled. The expansion ratio of the resin (filler) filled in the same core hole as above was changed to 1.35 to 1.60, and the impact attenuation rate and the vertical displacement were measured. The results are shown in Table 2. On the other hand, the measured values in the normal overlay repair method were an impact attenuation rate of 34.51% and a vertical displacement of 0.92. As a result, when the foaming ratio of the filler exceeds 1.55, the impact attenuation rate is extremely improved, the amount of vertical displacement is extremely large, and the foaming ratio of the filler is 1.40. It was found that both the impact attenuation rate and the vertical displacement amount were close to the values of the normal overlay method. Therefore, it has been found that the expansion ratio of the low foam modified polyurethane resin as the filler is preferably 1.40 to 1.55.

  In the first embodiment, 4 parts of an organopolysiloxane copolymer are added to 100 parts of a two-component room temperature curing polyurethane material having a specific gravity of 1.25, and mixed for 3 minutes using a hand mixer with a whisk. A low-foaming modified polyurethane resin material having a foaming ratio of 1.55 times and a specific gravity of 0.81 in which many closed cells exist was used. The core hole 7 was processed by drilling holes having a diameter of 10 mm and a depth of 10 mm with a pitch of 20 mm. FIG. 2 shows a plan view of the core hole 7. After filling the core hole 7 with the above resin, as shown in FIG. 1 3, an overcoating durable layer 2 mm is formed with 100% polyurethane resin, and an embossed finish layer is formed thereon with polyurethane resin. 1 mm was formed.

A comparison test was made between the one modified in the first embodiment and the one modified by another construction method. Other renovation methods were as follows.
In the “normal overlay” refurbishment method, the surface of the paved surface was scraped to a thickness of 3 mm, and a 2 mm thick overcoat durable layer and a 1 mm thick embossed finish layer were formed thereon with 100% polyurethane resin.
The “Mechaflo” refurbishment method applies the same low foaming modified polyurethane resin as in the first example with a foaming ratio of 1.55 to the surface scraped to a thickness of 3 mm in the same manner as described above. A 1 mm thick topcoat durable layer and a 1 mm thick embossed finish layer were formed from 100% polyurethane resin.
In the “grooving” renovation method, square grooves with a width of 5 mm and a depth of 7 mm are formed at a pitch of 20 mm on the surface cut to a thickness of 3 mm as described above, and this groove is filled with the same low foam modified polyurethane resin. Then, a 2 mm thick topcoat durable layer and a 1 mm thick embossed finish layer were formed on it with 100% polyurethane resin.
In the comparative test, the impact attenuation rate and the vertical displacement amount were measured by the test method specified by the IAAF in the “All Weather Track and Field Track Performance Standards”, and the impact attenuation rate increase from the state before the refurbishment, The vertical displacement increase amount and the vertical displacement increase rate were calculated and compared. The results are shown in Table 3.

  Furthermore, the running feeling when actually running on the pavement surface modified by each of the above methods was compared and verified. In addition, the verifier was made to wear spikes for land. The results are shown in Table 4. Thereby, it turned out that the repair method of an Example is excellent in driving | running feelings, such as a feeling of side shaking and a repulsive force, compared with the other repair method. Further, it was found that the feeling of side shake is the same as the increasing tendency of the vertical displacement.

  In the second embodiment, the shape of the core hole 7 is changed. As shown in FIG. 3, a cutting cutter 11 provided with cutting teeth on the periphery of a disk body is attached to a rotary shaft 12, and a core is obtained by scraping the pavement surface using a cutting device 10 that rotates the rotary shaft with a motor. A hole was formed. For this reason, the shape of the core hole 7 becomes an arc shape as shown in FIG. Moreover, the diameter of the cutting cutter 11 was 30 mm, and the core hole was formed by changing the thickness and the mounting pitch to the apparatus 10 as shown in Table 5. The core hole after the formation was filled with a low-foaming modified polyurethane resin having an expansion ratio of 1.55, and further, an overcoat durable layer and a surface embossed finish layer were formed thereon as in the first example. . The test results are shown in Table 5. Comparing this with the normal overlay repair method, it was found that the impact attenuation rate was improved in proportion to the volume ratio. Further, it was found that the vertical displacement amount is inferior when the volume ratio is less than 15.9%, and extremely increases when the volume ratio exceeds 55.0%.

  The present invention is not limited to the above-described embodiments, and can be freely modified within the scope of the claims. In particular, the shape of the core hole, the method of forming the core hole, and the type of filler are arbitrary.

Sectional drawing which showed the 1st Example of this invention in steps. The top view of the core hole of 1st Example. The schematic of the core hole formation apparatus of 2nd Example. The top view of the core hole of 2nd Example. Sectional drawing after renovation of 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base layer 2 Surface layer 3 Elastic layer 4 Topcoat durable layer 5 Surface embossing finish layer 6 Sharpening surface 7 Core hole 8 Filler (low foam modified polyurethane resin)

Claims (5)

The existing all-weather elastic pavement is scraped from the surface with a uniform thickness, and a number of core holes are formed on the scraped surface so that the volume ratio is 16 to 54% by volume. The core hole is filled with a polyurethane resin. All-weather elastic pavement repaired with a surface layer made of polyurethane resin. The all-weather elastic pavement repair body according to claim 1, wherein the filler is a low-foaming modified polyurethane resin having an expansion ratio of 1.40 to 1.55. The all-weather elastic pavement repair body according to claim 1, wherein the core hole has a cylindrical shape. The all-weather elastic pavement repair body according to claim 1, wherein the core hole has an arc shape. The surface of the existing all-weather elastic pavement is scraped to a uniform thickness, and a number of core holes are formed on the scraped surface so that the volume ratio is 16 to 54% by volume. The core hole is filled with a filler made of polyurethane resin. And the all-weather elastic pavement renovation method that forms a surface layer with polyurethane resin on it.

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