JPH03244701A - Application of asphalt based emulsion - Google Patents

Abstract

PURPOSE:To fill and repair a spot to be repaired within a short period of time by filling the recess to be repaired with ballast or ballast with their surfaces coated with a substance having affinity with asphalt, and then filling and integrally solidifying their gaps with asphalt based emulsion. CONSTITUTION:Cubic clocks of asphalt concrete with the side length of about 50mm are placed with gaps of about 8mm in a recess with its three sides sealed. The recess is filled with precoated chips 2 or No.7 ballast by as much amount as possible and as uniform as possible. The asphalt emulsion A or asphalt based emulsion B is poured and left as it is under the condition of about 30 deg.C and 65%RH. Prior to the filling of the asphalt based emulsion 3, a highly water absorbent polymer 4 is poured and sprayed in the recess and then the asphalt based emulsion 3 is filled and solidified. This process reduces the time for work execution, and improves reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a method for applying an asphalt-based emulsion suitable for repairing joints and cracks in asphalt and concrete.

(Prior Art) Asphalt emulsion, which is made by dispersing molten asphalt in water using an emulsifier, has been widely used as a joint material and crack repair material for concrete and asphalt because it is easy to handle and has good permeability.

However, asphalt emulsion is dried and solidified by waiting for the water, which is a dispersion medium, to evaporate, and since it has a high water content, it takes a long time to harden, especially in wide and deep joints and cracks. The problem was that it took time. In addition, in places where rainwater or groundwater tends to accumulate, such as roads, dams, and airport runways, curing is further delayed, and the emulsifier separates due to the action of this water, not only preventing it from performing its original function but also impairing its aesthetic appearance. There was also the problem of damage.

On the other hand, molten asphalt or molten asphalt mixed with rubber latex is also used as a joint filler and crack repair material, but unlike asphalt emulsion, these have a very slow curing speed and are cooled and solidified immediately after being applied. Because of this, it has poor permeability and cannot be filled deep enough into the crack, and the problem is that it closes the area near the surface, making the repaired area weak and prone to cracking again. In addition, injection special, 150℃ or higher for molten asphalt, 1 for molten asphalt mixed with rubber latex.
Because it requires heating at a fairly high temperature of 80 to 200℃, there are safety issues, and the heating tank is not large enough.
There was also the drawback that the work was complicated, such as having to use L.

(Problem to be solved by the invention) As mentioned above, asphalt emulsion is superior in permeability, workability, safety, etc. compared to molten asphalt or molten asphalt mixed with rubber latex, so it is suitable for use in concrete and asphalt. When used as a joint filler or crack filler, it takes a long time to harden, especially in wide or deep joints and cracks. In addition, in areas where city water or groundwater tends to accumulate, curing is further delayed, and there are also problems such as separation of the emulsifier and deterioration of aesthetic appearance.

The present invention has been made to solve these conventional problems, and it accelerates the hardening of asphalt emulsion and prevents the formation of wide and deep joints and cracks, as well as residual rainwater and groundwater. The purpose of the present invention is to provide a construction method for an asphalt emulsion that allows even joints and cracks to be filled and repaired in a short time.

[Structure of the Invention (Means for Solving the Problem)] The first aspect of the present invention is the construction method of an asphalt emulsion in which the asphalt emulsion is filled into a construction recess and hardened.
Prior to filling with the asphalt-based emulsion, crushed stone or crushed stone whose surface is coated with a substance that has an affinity for asphalt is filled into the construction recess, and then the asphalt-based emulsion is filled into the gap and cured integrally. A second aspect of the present invention is that, prior to filling the asphalt emulsion, a super absorbent polymer is injected and dispersed into the construction recess, and then the asphalt emulsion is filled and cured. Features.

Asphalt-based emulsions used in the present invention include generally used asphalt emulsions made by melting asphalt and emulsifying it with an emulsifier, or blending asphalt heated and melted with rubber latex, and further mixing an emulsifier and a dispersion stabilizer. (a) Asphalt emulsion and/or rubber/asphalt emulsion as detailed below may be used, but from the viewpoint of curing speed, mechanical properties of the solidified product, etc. asphalt emulsion;
(b) It is suitable to use an anionic emulsion of a polymer containing at least one kind of an acrylic acid compound or a methacrylic acid compound as a polymerization component. Note that all parts by weight and weight ratios shown below are converted to solid content.

That is, as the asphalt emulsion (a), it is preferable to melt asphalt such as natural asphalt or petroleum asphalt and emulsify it with a suitable emulsifier, especially an anionic emulsifier, since it has excellent penetration properties and workability. .

The rubber/asphalt emulsion is prepared by blending 100 parts by weight of rubber latex (hereinafter simply referred to as "parts") with 100 to 1,200 parts of heat-molten asphalt, and further mixing an anionic emulsifier and a dispersion stabilizer to contain water molecules fi.
An anionic high concentration emulsion of 8 to 35% by weight (hereinafter simply referred to as %) is suitable.

Rubber latexes include styrene-butadiene copolymer (SBR), vinylpyridine SBR, carboxy-modified SBR, acrylonitrile-butadiene copolymer (N
BR) etc. The asphalt may be natural asphalt or petroleum asphalt, and straight asphalt, blown asphalt, and others may be used alone or in combination. As the emulsifier, anionic emulsifiers such as fatty acid salts, higher alcohol sulfate ester salts, alkylhenzenesulfonates, and ronnates are suitable. As dispersion stabilizers, inorganic systems include bentonite,
There are sauces, etc., and organic types include polyvinyl alcohol, methylcellulose, hydroquine ethylcellulose, carboquine methylcellulose, sodium acrylate, starch, casein, etc.

These can be used alone or in combination, and the resulting rubber
Improves the stability of asphalt emulsion.

For the anionic emulsion (b), one or more acrylic acid compounds or methacrylic acid compounds, or these and styrene or vinyl acetate, are mixed with water and an emulsifier, and this mixture is mixed with an emulsifier such as ammonium persulfate. A product obtained by polymerizing by adding an acidic catalyst and stirring in warm water, and then neutralizing with an alkali such as aqueous asimonia to reduce pl+ to 7 to stop the reaction is used.

As acrylic acid compounds and methacrylic acid compounds,
Acrylic acid, acrylic ester, sodium polyacrylate, acrylic acid salts dimethylaminoethyl acrylate, isobutyl acrylate, diethylene glycol ethyl acrylate, 2-ethoxyethyl acrylate, ester acrylate, n-ester acrylate , tetrahydrofurfuryl acrylate, trimethylolpropane triacrylate, 2-hydroquine ethyl acrylate, 2-hydroxypropyl acrylate, 1,4-butanediolne acrylate, 1,6
-Hexanediol diacrylate, pentaerythritol triacrylate, lauryl tridecyl (mixture)
Acrylate, methyl methacrylate, ethyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, methacrylic acid,
2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, furfuryl tetrahuman methacrylate, ethylene dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene dimethacrylate, trimethylolpropane trimethacrylate, glycidyl methacrylate , n-butyl methacrylate, isobutyl methacrylate, 2-hydroxyethyl methacrylate, lauryl methacrylate, etc.

The combined ratio of component (a) and component (b) is 9 by weight.
9=1 to 50:50 is preferred.

In addition to the above-mentioned components, the asphalt emulsion described above contains rubber latex, such as SBR, vinylpyridine SB, etc., in order to improve mechanical properties such as elasticity of the solidified product.
R, carboxy-modified SBR, NBI? .

Latex such as natural rubber can be blended.

The blending amount of the rubber latex is such that the mixing ratio of the anionic emulsion (b) and the rubber latex is 1:1 by weight.
The ratio is preferably in the range of 00 to 240:100. When blending this rubber latex, the weight ratio of (a) component = (b) component ten rubber latex is 99:1.
It is preferable to set it as the range of 70:30.

In addition, in order to improve weather resistance, cold resistance, and flexibility,
Anti-aging agents and plasticizers can be added at a rate of 5% or less of the rubber component contained. Plasticizers include polybutene-1, phthalate ester compounds (dioctylhexyl phthalate, dimethyl phthalate, etc.), aliphatic dibasic acid ester compounds (diisodecyl succinate, etc.), and glycol ester compounds (diethylene glycol dibenzoate, etc.). , fatty acid ester compounds (butyl oleate, etc.), phosphate ester compounds (tricresyl, etc.), and the like.

Furthermore, fillers such as talc, activated clay, kaolin, and metal oxides can be added as thickeners, hardening accelerators, extenders, etc. within a range that does not impair the properties of the asphalt emulsion.

The crushed stone used in the present invention includes various types of crushed stone, porous crushed stone, etc., but in particular, so-called pre-coated chips, in which a mixture of asphalt and stone powder (calcium carbonate powder) is adhered to the surface of crushed stone, are used. It is preferable to use, for example, a mixture prepared by mixing No. 6 or No. 7 crushed stone with asphalt such as straight asphalt or blown asphalt and stone powder at a weight ratio of 3:1, and heating 1 to 5 parts per 100 parts of crushed stone. It is preferable to use the one obtained by mixing the two ingredients. Since asphalt is attached to the surface of the crushed stone, it has good affinity with the asphalt-based emulsion that is injected and filled later, and is strongly bonded to form a good solidified material.

Furthermore, the superabsorbent polymer used in the present invention includes:
Various commercially known superabsorbent polymers can be used, such as starch-acrylonitrile, starch-acrylic acid, carboxymethylcellulose, polyacrylic acid, vinyl alcohol-acrylic acid, and polyacrylamide.

These highly water-absorbent polymers have the ability to absorb and retain water several hundred to several thousand times their own weight, and can absorb water remaining at the bottom of cracks or seeping out (1) and drying asphalt-based emulsions. It promotes solidification and prevents separation of the emulsifier due to the action of water.

The method of the present invention is carried out, for example, as follows.

That is, FIGS. 1 to 3 are cross-sectional views showing an asphalt road or the like on which crack repair has been performed according to the present invention.

In the example shown in FIG. 1, a precoat chip 2 is filled in a crack 1, and an asphalt emulsion 3 is filled in the gap and solidified as one. In this repair, a pre-coat chip 2 is first filled into a crack 1, and then an asphalt emulsion 3 is injected into the crack 1 using a nozzle or a hose, etc., so that it fully penetrates into the crack 1, and then left as is.
The filled precoat chips 2 and asphalt emulsion 3 harden together over time, completing the repair.

In this example, by filling the precoat chip 2, the filling amount of the asphalt emulsion 3 is small, and as a result, the curing of the asphalt emulsion 3 is accelerated. Because it has excellent adhesion to one surface, it forms a solidified product with good properties, allowing for highly reliable repairs.

Note that it is desirable that the precoat chips 2 be filled as uniformly as possible with as few gaps as possible. Thereby, the curing of the asphalt emulsion 3 can be further promoted.

In the example shown in FIG. 2, superabsorbent polymer powder 4 is sprinkled into cracks 1, and then asphalt-based emulsion 3 is injected and filled, and the cracks are left to solidify naturally.

The asphalt emulsion 3 is coated with the asphalt emulsion 3 after residual water such as rainwater and exudate water such as underground water are removed by spraying the super absorbent polymer powder 4.
Since the emulsifier is injected and filled, curing is accelerated and the emulsifier does not separate and flow out from the cracks 1, so that a solidified product with a good appearance can be obtained.

Furthermore, in the example shown in FIG. 3, as in the example shown in FIG. Adhered super absorbent polymer coated precoated chip 5
is filled into the crack 1 prior to injection of the asphalt emulsion 3, and thereafter the asphalt emulsion 3 is injected and filled into the gap and solidified as one. In the super absorbent polymer coated precoated chip 5, the asphalt of the pre coat chip functions as a binder and adheres to the super absorbent polymer.

In this example, the water absorption effect of the superabsorbent polymer and the filling effect of the precoat chip 5 are synergistic, and the asphalt emulsion 3
Curing is further accelerated, and even if residual water such as rainwater or exudate water such as underground water is present, there will be no problem with curing, and the emulsifier will separate and the appearance will deteriorate. Not at all.

In the examples shown in FIGS. 1 and 3, the width of the crack 1 or joint is as wide as, for example, Lom- or more, and the depth is, for example, loO.
It is effective when the crack is as deep as +a+*, and the example shown in FIG. 2 is effective when the crack 1, joint, etc. are narrow.

The method of the present invention is not limited to the examples shown above,
It is desirable to carry out construction by considering the size of cracks and joints to be constructed, environmental conditions, presence of residual water, etc.

(Function) As described above, in the method of the present invention, the construction recess is filled with crushed stone or the like before the asphalt emulsion is injected and filled.
When eaten, due to its filling effect, the amount of asphalt-based emulsion to be filled can be reduced, so that curing is accelerated.

Furthermore, when superabsorbent polymers are injected and dispersed, residual water such as rainwater is removed due to their water absorption and filling effects, and the amount of asphalt emulsion to be filled can be reduced, so that hardening of the asphalt emulsion is prevented. The separation of the emulsifier is also prevented by IL'.

Furthermore, when these inorganic fillers and superabsorbent polymers are used together, their respective effects are additive and synergistic, accelerating the hardening of asphalt emulsions, and preventing separation of emulsifiers, resulting in changes in properties and appearance. A good solidification is formed,
It is possible to perform highly reliable construction.

(Example) Next, practical examples of the present invention will be described.

Asphalt emulsion A and asphalt emulsion B used in the following examples were prepared as follows, and pre-coated chips were prepared by mixing No. 7 crushed stone with straight asphalt and stone powder in a weight ratio of 3:1. It was obtained by mixing a mixture of 100 parts of crushed stone with 2 parts of crushed stone.

Asphalt emulsion A.

Asphalt emulsion A was prepared by heating and melting asphalt, pouring it into water in which an anionic emulsifier was dissolved at a ratio of asphalt:water at a ratio of 50:50, and stirring and dispersing it.

Asphalt emulsion B To the above asphalt emulsion A, 10 parts of methyl methacrylate monomer and IO part of styrene monomer were dissolved in 20 parts of water, and 4 parts of surfactant and i part of ammonium persulfate as a polymerization catalyst were added. After stirring at 80 to 90° C. for 6 hours to polymerize, aqueous ammonia was added to adjust the pH to 8.5, and the obtained copolymer elsion was mixed to prepare asphalt emulsion B.

Examples 1 to 4 As shown in Figure 1, pre-coated chips or No. Fill crushed stone as much as possible and uniformly, then asphalt emulsion A or asphalt emulsion B and leave it at 30°C and 65°C.
When left under conditions of %RH, curing proceeded rapidly, and a solidified body with good appearance and properties was formed within 6 days.

Example 5 Water was poured in advance into a recess formed in the same manner as above to a height of 0.5 mm.
In this state, as shown in Figure 2, 0.2 g of Aqualic CA (trade name, manufactured by Nippon Shokubai Kogyo Co., Ltd.) as a super absorbent polymer was sprinkled, and then asphalt emulsion B was injected. When the product was left as it was at 30° C. and 65% RH, curing proceeded rapidly, and there was no outflow due to separation of the emulsifier, and a solidified product with good appearance and properties was formed within 6 days.

Example 6 Water was preliminarily poured into the recess formed in the same manner as above to a height of 0.5II.
In this state, as shown in Figure 3, 0.2 g of Aqua Keep (trade name, manufactured by Seitetsu Kagaku Kogyo Co., Ltd.) is sprayed as a super absorbent polymer, and Aqualic CA is further added as a super absorbent polymer. Filled with pre-coated chips coated with and then injected with asphalt emulsion B.
When it was left as it was at 30° C. and 65% R11, curing proceeded rapidly, and there was no outflow due to separation of the emulsifier, and a solidified product with good appearance and properties was formed within 6 days.

Example 7.8 Asphalt-based emulsion B was press-fitted in the same manner as in Example 5, except that the superabsorbent polymer was not filled, and instead No. 7 crushed stone or pre-coated chips were filled up to the surface of the recesses, and 30 When left under conditions of ℃ and 65% RH,
Curing proceeded quickly, and a solidified product with good properties was formed within 6 days.

In order to investigate the characteristics of the solidified bodies according to the above examples, various tests were conducted using the following methods.

Adhesion test After 6 days had elapsed from the injection of the near-asphalt emulsion, a cubic block of asphalt concrete sandwiching the solidified material was pulled on both sides, and its adhesive strength was measured at 23°C.

Tensile test: In this test, apart from the above examples, the same ingredients as in each example were filled or sprayed by pressure in the same method as in each example at room temperature into a predetermined mold with a thickness of 10 inches. ,30℃,
After being left under 65% R1+ conditions for 6 days, JIS K
The maximum tensile strength was measured under the conditions of 23° C. and 50 m+a/min according to 2208. In addition, the water added in advance is
The height of the formwork was limited to 1 mm.

Permeability and curing test: In this test as well, apart from each of the above examples, each component was filled in a cylindrical plastic container (height: 60 mm, diameter: 45 mm) in the same ratio and method as in the examples. Or spray by injection,
Observe the penetration status of asphalt emulsion, and after injection,
It was left to stand for 6 days at 30° C. and 65% RH, and the state of curing after being left was examined. Note that the water added in advance was limited to a height of 10 mm in the container.

The above results are shown in the table together with the filling components.

For comparison, asphalt-based emulsion B was filled and solidified in the same manner as in Example 1 except that river sand was filled instead of pre-coated chips (Comparative Example 1), and asphalt-based emulsion B only was used in Example 1. Filled and solidified example (Comparative example 2
), the same type of test was also conducted for an example in which only asphalt emulsion B was filled and solidified in Example 5 (Comparative Example 3), and an example in which conventional heated molten asphalt was filled and solidified (Comparative Example 4). These results are also shown in the table.

(The following is a blank space) [Effects of the Invention] As explained above, according to the method of the present invention, the construction recesses are filled with crushed stone or the like or superabsorbent polymers are injected before filling with the asphalt emulsion. (5), the curing of the asphalt emulsion is accelerated and the construction time can be substantially shortened. Also, depending on the superabsorbent polymer, separation of the emulsifier due to water remaining in the recesses can be prevented. .

Therefore, even if the joints and cracks are wide and deep, or where there is residual rainwater or groundwater, it is possible to fill and repair them within a short period of time.

[Brief explanation of drawings]

1 to 3 are cross-sectional views showing embodiments of the present invention. 1-... Crack 2... Pre-coat chip 3... Asphalt emulsion 4... Super water absorbent polymer powder 5... Super water absorbent polymer coated pre coat chip

Claims (2)

[Claims] (1) In an asphalt-based emulsion construction method in which an asphalt-based emulsion is filled into a construction recess and hardened, prior to filling the asphalt-based emulsion, crushed stone or crushed stone whose surface is coated with a substance that has an affinity for asphalt is used. A method for applying an asphalt-based emulsion, which comprises filling the construction recess, and then filling the gap with the asphalt-based emulsion and curing the asphalt-based emulsion integrally. (2) In an asphalt-based emulsion construction method in which an asphalt-based emulsion is filled into a construction recess and hardened, prior to filling the asphalt-based emulsion, a superabsorbent polymer is injected and dispersed into the construction recess, and then the asphalt emulsion is An asphalt-based emulsion construction method characterized by filling and curing the asphalt-based emulsion.