JPH11209909A - Paving structure for paving airport and its construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paving structure for paving an airport and its construction method which is excellent in torsion resistance, and dispenses with the provision of a joint and heating in the case of execution. SOLUTION: A room temperature asphalt mixture including an aggregate, an asphalt emulsion mixed with the aggregate in a state where a volume is increased by bubbling and a hydraulic setting inorganic material is paved, and after paving, a thermoplastic high-molecular polymer is supplied on the room temperature asphalt mixture and rollingly pressed to form a surface layer integrated with the paved room temperature asphalt mixture. Thus, a paving structure for paving an air port constructed in this way can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pavement structure for an airport pavement and a method for constructing the same, and more particularly, to a pavement structure suitable for a place exposed to an extremely heavy load such as an airport runway, taxiway or apron. It concerns the construction method.

[0002]

2. Description of the Related Art Airport taxiways and apron pavement structures are:
Since the overhead load is larger than that of a general road, it is necessary to withstand a large torsional force generated when an aircraft corners on a taxiway or an end of a runway.

Conventionally, cement concrete pavement excellent in load resistance and oil resistance has been frequently used for airport pavement exposed to such severe conditions. However, cement concrete pavement greatly expands and contracts with temperature change. However, it is essential to provide joints that absorb the expansion and contraction. However, the joints provided are not preferable because they cause vibrations to aircraft and vehicles passing over the joints, and not only make passengers uncomfortable, but also cause collapse of loaded cargo.

[0004] In addition, although airport pavements are constructed using a heated asphalt mixture, pavements using a heated asphalt mixture do not need to provide joints unlike cement concrete pavements. However, as compared with cement concrete pavement, there is a drawback that the torsion resistance by an aircraft or the like with a super heavy load is inferior, and the load resistance and flow resistance are inferior. Moreover, the heated asphalt mixture needs to be heated at the time of use, and there is a problem in that generation of CO ₂ gas which contributes to global warming is accompanied.

In recent years, the use of a room temperature mixture using asphalt emulsion and cement has been studied as an alternative to the conventional airport pavement, but it is still unsatisfactory in the load resistance obtained, particularly in the twist resistance. What can be done has not been obtained.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned various disadvantages of the prior art.
It is an object of the present invention to provide a pavement structure for airport pavement, which has excellent load resistance, particularly excellent torsion resistance, does not require any joints, and does not require heating even during construction, and a method for constructing the same. is there.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted studies to solve the above problems, and as a result, the aggregate and the asphalt emulsion used in the room temperature mixture have been increased in volume by foaming the asphalt emulsion. And the aggregate surface is sufficiently covered with an asphalt emulsion, and a hydraulic inorganic material is used, and after paving the pavement, a thermoplastic polymer is supplied and then compacted. As a result, it has been found that a pavement structure for an airport pavement having excellent load resistance, particularly excellent torsion resistance, can be obtained, and the present invention has been completed.

That is, the present invention provides a room temperature asphalt mixture containing an aggregate, an asphalt emulsion mixed with the aggregate in a state where the volume is increased by foaming, and a hydraulic inorganic material. A method for constructing a pavement structure for an airport pavement that forms a surface layer integrated with a paved room temperature asphalt mixture by supplying a thermoplastic high molecular weight polymer onto the mixture and compacting, and thus constructed. An object of the present invention is to solve the above-mentioned problem by providing a pavement structure for an airport pavement.

In the present invention, the aggregate is mixed with the asphalt emulsion in a state where the volume of the asphalt emulsion is increased by foaming. Means for bubbling the asphalt emulsion is not particularly limited, but due to the properties of the asphalt emulsion, it is preferable to employ stirring which allows easy bubbling at normal temperature and normal pressure. The asphalt emulsion used in the present invention foams by stirring, and its volume increases. Although there is no particular limitation on the amount of increase in the volume, it is usually 2 to 15 times the original volume.
About twice is preferable. If the increase in volume is less than twice, the effect of uniform mixing due to the increase in volume cannot be sufficiently expected.
Even if the volume is increased more than 15 times, there is not much difference in the effect of the uniform mixing. Usually, 3 to 8 volumes before stirring
About twice is preferable.

The stirring means may be of any type, but it is preferable to use a mechanical stirring means such as a mixer for rotating the rotating blades. If necessary, physical stirring means for blowing air may be used in combination, or water or the like may be appropriately added.

The order of mixing the aggregate and the asphalt emulsion is not limited. When fine aggregate and coarse aggregate are used as the aggregate, the fine aggregate and the coarse aggregate are mixed with each other in advance. Thereafter, it may be mixed with the asphalt emulsion in a state where the volume is increased by foaming.After mixing the coarse aggregate with the asphalt emulsion in a state where the volume is increased by foaming, the mixture is mixed with fine aggregate or fine aggregate. The aggregate and the asphalt emulsion whose volume has been increased by foaming may be added and further mixed. However, asphalt emulsion in which the volume is increased by fine aggregate and foaming, and asphalt emulsion in which the volume is increased by foaming and coarse aggregate are separately mixed, and then both mixtures are mixed. The periphery of the coarse aggregate coated with the emulsion can be uniformly covered with the fine aggregate also coated with the asphalt emulsion, so that a stronger pavement can be obtained. In addition, when the aggregate also includes a filler, the filler is mixed with the fine aggregate in advance, or handled with the fine aggregate,
It is preferred to mix as fine aggregate.

According to the knowledge of the present inventors, an asphalt emulsion in which the volume is increased by foaming is used even if the aggregate used contains a large amount of fine particles having a large specific surface area. The surface of the fine aggregate can be almost completely covered, and a coating film of asphalt emulsion is uniformly formed on the surface of the aggregate to prevent the aggregate from being aggregated. Moreover, as a result of the asphalt mixture being sufficiently covered with the asphalt surface, the room-temperature asphalt mixture thus obtained exhibits good physical properties even after solidification, and a thermoplastic polymer polymer formed integrally on the surface. Coupled with the surface layer of the object,
It is intended to impart excellent load resistance and torsion resistance to the pavement structure to be constructed.

In the present invention, the room temperature asphalt mixture contains a hydraulic inorganic material in addition to the aggregate and the asphalt emulsion. Hydraulic inorganic materials are effective for early development of the hardness of the asphalt mixture at room temperature and are necessary for strengthening the cured mixture. There is no particular limitation on the timing of mixing the hydraulic inorganic material, and the hydraulic inorganic material, together with the aggregate, may be mixed with an asphalt emulsion having an increased foaming volume, or after mixing with the aggregate,
It may be mixed with an asphalt emulsion having an increased foaming volume, but the aggregate and the asphalt emulsion are mixed,
After the aggregate surface is coated with asphalt emulsion,
It is most preferable to mix a hydraulic inorganic material because the asphalt emulsion and the hydraulic inorganic material effectively function as a binder for the aggregate.

Further, the room temperature asphalt mixture of the present invention can provide a pavement structure more excellent in load resistance and twist resistance by further containing a thermoplastic polymer. The thermoplastic polymer contained in the room temperature asphalt mixture may be the same as or different from the thermoplastic polymer supplied after paving. If the same is used, the room temperature asphalt mixture and the thermoplastic high molecular weight polymer supplied after paving are well adapted and convenient.

The room temperature asphalt mixture of the present invention is paved at a predetermined location, and after the paving, a thermoplastic polymer is supplied onto the room temperature asphalt mixture. The means for supplying the thermoplastic polymer is not particularly limited as long as the thermoplastic polymer can be supplied almost uniformly on the room temperature asphalt mixture. Spraying, coating, spraying, etc. Means can be adopted. In addition, it is preferable to spread the pavement-mixed room-temperature asphalt mixture before supplying the thermoplastic high-molecular polymer in order to form a uniform surface layer. A part or all of the supplied thermoplastic high molecular weight polymer penetrated into the paved room temperature asphalt mixture, and if only a part of the supplied thermoplastic polymer did not permeate onto the room temperature asphalt mixture, A layer of high molecular weight polymer is formed. In the present invention, the compaction is performed after the thermoplastic polymer is supplied, after the thermoplastic polymer has sufficiently penetrated into the paved room temperature asphalt mixture. The thermoplastic polymer that has permeated, compacted and compacted with the cold asphalt mixture solidifies in a short time and forms a surface layer integrated with the paved cold asphalt mixture. The surface layer constructed in this way is
It is not always necessary to be the uppermost layer, and it goes without saying that various protective layers and other surface layers generally used can be further constructed on the constructed surface layer.

The pavement structure for airport pavement thus constructed according to the present invention is a pavement in which aggregates are strongly bonded by asphalt and a hydraulic inorganic material, and a solid surface integrated with the pavement. Since it has a layer, it can not only sufficiently withstand the super heavy load even when the super heavy load of the aircraft or the like is loaded, but also sufficiently exerts a large torsion force on the surface due to the cornering of the aircraft or the like. It can withstand twisting force. In addition, upon construction, there is no need to heat the material, which saves energy and does not generate CO ₂ . Furthermore, it is an excellent pavement structure in which expansion and contraction due to a temperature change is small and it is not necessary to provide joints.

The airport pavement pavement structure and the method of constructing the same according to the present invention are particularly suitable for an airport pavement that is subjected to an extremely heavy load. However, it is needless to say that the pavement structure can also be applied to a pavement at a port facility. is there.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a pavement structure for airport paving according to the present invention and a construction method thereof will be described in detail.

<Asphalt Emulsion> The asphalt emulsion used in the room temperature asphalt mixture of the present invention is natural asphalt such as lake asphalt, straight asphalt, blown asphalt, semi-blown asphalt, solvent deasphalted asphalt (for example, propane deasphalted asphalt). Bituminous substances such as petroleum asphalt, heavy oil, tar, pitch, etc., or a mixture of two or more kinds thereof, using various surfactants or emulsifiers such as clay (for example, bentonite); , A dispersing agent, a protective colloid and the like are added as necessary, and the mixture is emulsified in water by a suitable emulsifying machine such as a colloid mill, a homogenizer and a homomixer. The asphalt preferably has a penetration at 25 ° C. of about 40 to 500 in consideration of the properties after curing.

As the emulsifier, any of a cationic type, an anionic type and an amphoteric type can be used.

Examples of the cationic emulsifier usable in the present invention include aliphatic or alicyclic monoamines, diamines, triamines, amidoamines having a long-chain alkyl group.
Polyaminoethylimidazoline, long-chain hydroxyalkyldiamine, rosinamine, ethylene oxide adducts of these amines, amine oxides, or water-soluble compounds obtained by reacting these amine surfactants with acids such as hydrochloric acid, sulfamic acid and acetic acid. Examples thereof include water-dispersible salts, and quaternary ammonium salts of these amine surfactants. In addition, a nonionic surfactant such as a polyoxyethylene alkyl ether, a polyoxyethylene alkyl allyl ether, or an oxyethylene / oxypropylene block copolymer can be used in combination with these surfactants.

The anionic emulsifiers usable in the present invention include higher alcohol sulfates, alkyl allyl sulfonates, alkyl benzene sulfonates, α-olefin sulfonates, higher alcohol ethoxylates, higher alcohol ethoxylate sulfates, and the like. Soap, naphthalene sulfonate and modified formalin,
Examples thereof include alkali lignin salts, lignin sulfonates, alkali salts of casein, and polyacrylates.

Examples of the amphoteric emulsifier which can be used in the present invention include alkylphenols, mono- and polyhydric alcohol acids, adducts of alkylene oxides such as aliphatics, aliphatic amines, aliphatic amides and ethanolamines. Is mentioned.

The dispersing agents and protective colloids used in asphalt emulsions include sodium naphthalenesulfonate, casein, alginic acid, gelatin, carboxymethylcellulose, ethylcellulose, hydroxyethylcellulose, polyvinyl alcohol, sodium polyacrylate, ligninsulfonate, Nitrohumates and the like.

In the asphalt emulsion used in the present invention, natural rubber or various synthetic rubbers can be used alone or in combination with the above-mentioned emulsified and dispersed bitumen. As the synthetic rubber, various synthetic rubbers such as chloroprene rubber, styrene / isoprene copolymer rubber, polyisoprene rubber, polybutadiene rubber, and styrene / butadiene copolymer rubber are used alone or in combination. In particular, when chloroprene rubber or styrene-isoprene copolymer rubber is used, characteristics at high and low temperatures are improved, which is preferable. Also, Mooney viscosity is
A solid or latex type, about 10 to 100, is preferable because good results are obtained.

The asphalt emulsion used in the present invention also includes a modified asphalt obtained by adding the following polymer in addition to rubber to bitumen material, and emulsifying the modified asphalt to form an asphalt emulsion. That is, as a polymer to be added, a synthetic high-molecular polymer resin such as ethylene-vinyl acetate copolymer, polyethyl acrylate, polymethyl acrylate, polyacrylic acid, or polyvinyl chloride, a coumarone resin, a carbonate resin, a xylene resin, and urea formalin Resins, synthetic resins such as alkyd resins, and natural resins such as rosin and terpene resins.

To these asphalt emulsions, ultraviolet absorbers, various additives, viscosity modifiers, etc. are added for the purpose of improving heat resistance, preventing deterioration due to ultraviolet rays, improving workability, and improving adhesiveness. You may.

The solid content in the asphalt emulsion used in the present invention is preferably in the range of 40 to 80% by weight.
If the solid content is less than 40% by weight, this does not mean that it cannot be particularly used, but the room-temperature asphalt mixture layer tends to be slightly inferior in terms of adhesiveness and viscoelasticity, which is not preferable. On the other hand, if the solid content exceeds 80% by weight, it does not mean that the solid content cannot be particularly used, but the viscosity is increased and the workability tends to be slightly inferior.

In the case of an asphalt emulsion containing a rubber or a polymer, the amount of the solid content of the rubber or the polymer is 2 to 20% by weight based on 100% by weight of the asphalt emulsion.
Is preferable. If the solid content of the rubber or polymer is less than 2% by weight, this does not mean that it cannot be particularly used, but the room-temperature asphalt mixture layer tends to be slightly inferior in terms of adhesion and viscoelasticity, which is not preferable. On the other hand, if the content of the solid content of the rubber or the polymer exceeds 20% by weight, it does not mean that it cannot be particularly used, but the viscosity is increased and the workability tends to be slightly inferior.

The decomposition of asphalt emulsion generally depends on spontaneous decomposition, but in some cases, it may be forcibly decomposed using a decomposition accelerator. Examples of the decomposition promoting agent include an alkaline compound of a divalent metal. The alkaline compound of a divalent metal is a compound mainly containing an alkali metal such as Ca or Mg or a compound containing an oxide thereof. For example, oxides such as Cao and MgO;
Hydroxides such as (OH) ₂ and Mg (OH) ₂ ; ordinary Portland cement, early-strength Portland cement, ultra-high-strength Portland cement mainly composed of calcium silicate, calcium aluminate, calcium sulfate, calcium oxide, etc. Medium heat Portland cement, white Portland cement, blast furnace cement, silica cement, fly ash cement, alumina cement, expansion cement,
Examples include cements such as sulfate-resistant cement, jet cement, blast furnace colloid cement, and colloid cement. These decomposition accelerators may be used alone or in combination of two or more.

The mixing ratio of the decomposition accelerator can vary depending on the type of the aggregate, the type of the decomposition accelerator itself, the composition of the asphalt emulsion, and the like, but is usually up to about 6 parts by weight per 100 parts by weight of the aggregate. is there. When the proportion of the decomposition accelerator exceeds 6 parts by weight, the asphalt emulsion adhesiveness and coating resistance to the aggregate tend to decrease rather.

The amount of the asphalt emulsion used in the room temperature asphalt mixture used in the present invention is a solid content based on 100 parts by weight of the aggregate (when an additive is used in combination,
(Including additives), usually about 2 to 12 parts by weight, more preferably about 4 to 10 parts by weight. If the amount of the asphalt emulsion is less than 2 parts by weight, sufficient adhesiveness to be provided by the asphalt cannot be obtained, and the flexibility of the pavement decreases, while the amount of the asphalt emulsion is 12 parts by weight. If it exceeds, the viscosity of the mixture increases, which is not only unfavorable in terms of workability but also lowers the stability of the pavement.

<Aggregate> Aggregate used in the present invention is an aggregate for pavement described in "Asphalt Pavement Guidelines" issued by the Japan Road Association, and includes crushed stone, crushed stone, gravel, steel slag, and the like. It is. Further, asphalt-coated aggregates obtained by coating these aggregates with asphalt, recycled aggregates, and the like can also be used. Other granular materials similar to these include artificially fired aggregates, fired expanded aggregates, artificial lightweight aggregates, ceramic particles, luxovite, Sinopearl, aluminum particles, plastic particles, ceramics, emery, and the like.

These aggregates are roughly classified into coarse aggregates, fine aggregates, and fillers.
mm aggregate that has a particle size that stops at the screen.
Aggregate having a particle size that passes through a 2.5 mm screen and stops at a 0.074 mm screen. The filler is
Particles that pass through a 0.074 mm screen.

The coarse aggregate used in the present invention is generally No. 7 crushed stone having a particle size range of 2.5 to 5 mm, and a particle size range of 5 to 5 mm.
No. 6 crushed stone of ~ 13mm, 5 of particle size range of 13 ~ 20mm
No. 4 crushed stones having a particle size range of 20 to 30 mm are available, and crushed stones obtained by mixing one or two or more kinds thereof, and crushed stones synthesized can be used. These aggregates are preferably coated with about 0.3 to 1% by weight of asphalt emulsion or straight asphalt based on the aggregate.

The fine aggregate used in the present invention includes:
For example, river sand, hill sand, mountain sand, screenings, crushed dust, silica sand, artificial aggregate and the like can be mentioned, and one or more of these fine aggregates can be used.

As the filler used in the present invention, for example, fillers of screenings, stone powder, incinerator ash,
Clay, talc, fly ash, carbon black, etc. In addition, rubber powder, cork powder, wood powder, resin powder, pulp, artificial aggregate,
If it passes through a 5 mm sieve, it can be used as a filler. These fillers are also one or two
More than one species can be used.

The distinction between the coarse aggregate, the fine aggregate, and the filler as described above is for the purpose of facilitating the understanding of the properties of the aggregate and the design of the particle size. If it can be obtained, use an aggregate having a continuous particle size in which any two or more of coarse aggregate, fine aggregate, and filler are mixed, for example, a crushed crushed stone, crusher run, cut crushed stone, scraped gravel, etc. It is also possible.

<Hydraulic Inorganic Material> Examples of the hydraulic inorganic material to be mixed with the room temperature asphalt mixture used in the present invention include cement, anhydrous gypsum, hemihydrate gypsum, and powdery slag.

As the cement to be used, ordinary Portland cement, early-strength Portland cement, ultra-high-strength Portland cement, moderately heated Portland cement, white Portland cement, blast furnace cement, silica cement, alumina cement, expansion cement, blast furnace colloid cement, colloid Examples include cement, ultra-rapid hardening cement, white cement, fly ash cement, sulfate-resistant cement, jet cement, and the like. These hydraulic inorganic materials may be used alone or in combination of two or more. Further, water or a known admixture material for cement (for example, a shrinkage compensating material, a hardening accelerator, a hardening retardant, a dispersion Agents, air entrainers, thickeners, water reducing agents, fillers, etc.).

The amount of the hydraulic inorganic material used depends on the amount of the aggregate 10
It is in the range of 1 to 20 parts by weight, preferably 3 to 18 parts by weight, based on 0 parts by weight. If the amount of the hydraulic inorganic material is less than 1 part by weight, the stability of the cured body of the room temperature asphalt mixture will be reduced, whereas if it exceeds 20 parts by weight, the rigidity of the cured body will be excessive and the flexibility will not be exhibited. .

<Thermoplastic polymer> As the thermoplastic polymer used in the present invention, for example, ethylene
Examples thereof include vinyl acetate copolymers, ethylene acrylate copolymers, polyethylene, vinyl acetate acrylate copolymers, and one or more of these are used in combination.

The thermoplastic polymer includes, for example,
Natural rubber, rattle, cyclized rubber, styrene / butadiene rubber, styrene / isoprene rubber, isoprene rubber, polyisobutylene rubber, butadiene rubber, chloroprene rubber, butyl rubber, halogenated butyl rubber, chlorinated polyethylene, chlorosulfonated polyethylene, ethylene propylene rubber Rubber such as EPT rubber, olefin rubber, styrene / butadiene block copolymer rubber, and styrene / isoprene block copolymer rubber.

These thermoplastic polymers are, for example,
Powders, latexes, emulsions, aqueous ones, and various shapes and forms can be used. Among them, latexes, emulsions, and aqueous ones obtained by diluting these are available. preferable. The concentration of the evaporation residue (solid matter) of the latex, emulsion, or aqueous thermoplastic polymer polymer obtained by diluting the latex, emulsion, or the like is usually about 20 to 80% by weight. The concentration of the evaporation residue is preferably as high as possible.

These thermoplastic polymers are used as a material to be added to and mixed with the room-temperature asphalt mixture, or are supplied from above the room-temperature asphalt mixture after paving the room-temperature asphalt mixture, and are cured by heating to form a surface layer. It can also be used as a plastic polymer.

When the thermoplastic polymer is used as a material to be added to and mixed with a room temperature asphalt mixture,
The compounding ratio is 1 to 100% by weight based on the cement,
Desirably, it is in the range of 20 to 40% by weight. When the blending ratio of the thermoplastic polymer is less than 1% by weight, the effect of the addition is not exhibited. On the other hand, when the blending ratio of the thermoplastic polymer exceeds 100% by weight, the amount of water in the mixture increases, which is not preferable.

When the thermoplastic high molecular weight polymer is supplied onto a pavement room temperature asphalt mixture, it is preferable to use the thermoplastic high molecular weight polymer by mixing and stirring with water at the time of use. The mixing ratio thereof is about 30 to 60 parts by weight, preferably about 40 to 50 parts by weight of a latex, emulsion, or aqueous thermoplastic polymer with respect to 100 parts by weight of water. When the blending ratio of the thermoplastic polymer is less than 30 parts by weight, the adhesive strength to the room temperature asphalt mixture after curing and the grasping power are inferior, whereas the blending ratio of the thermoplastic polymer is 60%. Exceeding the parts by weight not only reduces the ability to penetrate into the paved cold asphalt mixture, but also causes the cohesive force to be too strong to easily peel off the hardened cold asphalt mixture, and is not economical. . In addition, when supplying on a paved room-temperature asphalt mixture, the amount of these thermoplastic high-polymers used is, in terms of solids,
About 0.1 to 0.5 kg / m ² is preferable.

<Other Additives> In addition to the above-mentioned materials, the room temperature asphalt mixture used in the present invention includes glass powder, iron powder, metal powder, organic and / or inorganic color pigments, and organic and / or inorganic color pigments. A fiber material or the like may be added, and these additives are appropriately selected according to the application. For example,
When coloring the cured product of the asphalt mixture at room temperature, a coloring pigment is used, and a fiber material is added to improve the strength of the cured product. As the fiber material to be used, synthetic fibers such as polyester, polyamide, aromatic polyamide, polypropylene, vinylon, acrylic, and polyvinylidene chloride, or semi-synthetic fibers, natural fibers, glass fibers, recycled fibers, carbon fibers, metal fibers, and the like, Various materials are used, and among them, alkali-resistant glass fibers are preferable.

In the present invention, a foaming agent and a foaming agent can be further added to the room temperature asphalt mixture. The blowing agent used in the present invention, for example, aluminum powder, hydrogen peroxide and salad powder, hydrochloric acid and baking soda, magnesium and lead and alkali, calcium carbide and water, etc., the amount used, asphalt emulsion And 0.01 ~
A range of 0.015% by weight is preferred. The foaming agents used in the present invention include, for example, resin soaps, synthetic surfactants such as alkyl allyl sulfonic acid, protein derivatives such as casein and gelatin, and polymeric surfactants such as maleic acid. The amount used is preferably in the range of 0.05 to 0.5% by weight based on the asphalt emulsion.

<Production of Room Temperature Asphalt Mixture> The room temperature asphalt mixture used in the present invention is produced as follows.

First, before mixing the aggregate and the asphalt emulsion, it is necessary to foam the asphalt emulsion to increase its volume. In the present invention, asphalt emulsion foams by an easy means of forced agitation to increase its volume. That is, for example, by using a stirrer provided with a stirring blade on a rotating shaft, the asphalt emulsion used in the present invention can be easily foamed, and its volume can be increased. Normal,
As the stirring time increases, the volume gradually increases, but after a certain value, the volume does not increase even if stirring is performed for a longer time. When a further increase in volume is desired, it is preferable to use a foaming agent or a foaming agent, and furthermore, water or the like. The foaming agent and the foaming agent may be mixed with the asphalt emulsion before stirring, or may be used by mixing water and the foaming agent in advance, stirring and foaming, and mixing with the asphalt emulsion. You may. Further, by using a means for forcibly blowing air or the like in addition to the mechanical stirring for rotating the stirring blade, the stirring efficiency is increased, and a predetermined volume increase can be obtained in a short time.

As the stirring means, not only a rotary stirrer for rotating the stirring blade as described above, but also, for example,
A vibrating stirrer that vibrates the blades may be used, and any stirring means may be used as long as the asphalt emulsion can be stirred at room temperature and its volume can be increased by bubbling.

In the present invention, it is necessary to mix the asphalt emulsion and the aggregate in a state where the volume of the asphalt emulsion has increased due to foaming, and it is sufficient if the volume of the asphalt emulsion is increased at the time of mixing. There are no particular restrictions on the mixing method or order of mixing,
The mixing of both can be performed, for example, by the following procedure.

The coarse aggregate and the asphalt emulsion whose volume has been increased by bubbling are mixed, and separately, the fine aggregate and the asphalt emulsion whose volume has been increased by bubbling are mixed separately. After mixing, the two mixtures are combined and mixed more thoroughly. At this time, as a mixer for mixing the two mixtures together, a mixer different from a mixer in which coarse aggregate and asphalt emulsion are mixed and a mixer in which fine aggregate and asphalt emulsion are mixed may be used, Further, a mixer in which coarse aggregate and asphalt emulsion are mixed may be used by putting a mixture of fine aggregate and asphalt emulsion into a mixer in which coarse aggregate and asphalt emulsion are mixed. Conversely, a mixer in which fine aggregate and asphalt emulsion are mixed may be used by adding a mixture of coarse aggregate and asphalt emulsion to a mixer in which fine aggregate and asphalt emulsion are mixed.

Alternatively, when one mixer is used, first, the coarse aggregate and the asphalt emulsion having an increased volume are mixed, and then the fine aggregate and the asphalt emulsion having an increased volume are mixed in the same mixer. It is preferable to add and mix the fine aggregate and the asphalt emulsion having the increased volume in the reverse order, and then mix the coarse aggregate and the asphalt having the increased volume in the same mixer. The emulsion may be charged and further mixed.

In any of the above cases, the asphalt emulsion and each of the aggregates may be mixed by putting the whole amount to be mixed into the mixer at one time, or may be put in plural times. You may mix. If the asphalt emulsion is injected in a plurality of times, a thin layer of asphalt is formed around the aggregate, which has the great advantage that the asphalt adheres to the aggregate uniformly and firmly. Can be It goes without saying that in these mixing steps, water may be added to adjust the consistency in order to improve workability.

Further, after the coarse aggregate and the fine aggregate are sufficiently mixed in advance, the asphalt emulsion having an increased volume may be added at once or dividedly and mixed. When using aggregates in which coarse and fine aggregates are inseparably mixed from the beginning, such aggregates may be coated with an increased volume of asphalt emulsion at once or in multiples. Put in a batch and mix.

The asphalt emulsion is usually used in an amount of 1/3 to 2% of the total amount, although it depends on the ratio of the coarse aggregate and the fine aggregate used.
/ 3 is used for mixing with coarse aggregate, and the remaining 2/3 to 1/3
Is preferably used for mixing with fine aggregate.

When a filler is used, it is preferable to use it by mixing it with the fine aggregate in advance or to put it in a mixer together with the fine aggregate to mix. Further, a filler can be used instead of the fine aggregate. When the coarse aggregate is not used, it is needless to say that only the fine aggregate and / or the filler may be mixed with the asphalt emulsion having the increased volume.

When adding a hydraulic inorganic material, a thermoplastic polymer, and other additives, it is necessary to add them at the stage where the coarse and fine aggregates and the asphalt emulsion are sufficiently mixed. Is preferred. Admixtures for water and cement
It may be previously mixed with the hydraulic inorganic material, or may be added and mixed simultaneously with or before or after the hydraulic inorganic material.

The mixer to be used is not particularly limited, and for example, a continuous mixer, a pug mill mixer, a pan mixer, or a tilting mixer is used. The production of the room-temperature asphalt mixture of the present invention can be easily carried out both at a plant and at a construction site.

The pot life of the room temperature asphalt mixture used in the present invention can be appropriately adjusted depending on the mixing ratio of each material and the like, but the time required for transportation and construction and the built pavement structure are used at an early stage. In general, it is desirable to set the time to about 2 hours in consideration of the necessity and the like. When the production site of the room-temperature asphalt mixture, the construction conditions, and the like are different, it is a matter of course that a different pot life is desirable.

<Construction Step> The construction for constructing the pavement structure of the present invention is, for example, as follows.

The produced room temperature asphalt mixture is laid on the place to be laid using an asphalt finisher or the like, and evenly spread, and then the latex or emulsion is formed on the spread room temperature asphalt mixture. Alternatively, an aqueous thermoplastic polymer obtained by diluting these with water is immediately supplied. The supply is carried out, for example, by spraying or spraying uniformly using an engine sprayer or a distributor. In addition, the supply of the thermoplastic polymer is not limited to spraying or spraying, such as coating or flowing down.
This can be done by various methods.

At the stage where the solution containing the supplied thermoplastic high molecular weight polymer has sufficiently penetrated into the cold asphalt mixture, preferably at a stage where a part of the solution slightly remains on the spread cold asphalt mixture. And compacted by a compactor. At the time of compaction, a part of the permeated solution floats up on the compaction surface so as to bleed, and after the solution solidifies, it forms a surface layer integrally with the solidified room temperature asphalt mixture. There is no problem in particular.

Hereinafter, the present invention will be further described with reference to examples, but it is needless to say that the present invention is not limited to these examples.

[0067]

EXAMPLE Various specimens were prepared, and the stationary stability (S
DS). The materials used and the test methods are as follows.

<Materials Used> The materials used for producing the asphalt mixture are as follows. Aggregate Coarse aggregate: No. 6 crushed stone, No. 7 crushed stone (Kuzu, Tochigi prefecture) Fine aggregate and filler: coarse sand, fine sand (Kinugawa, Tochigi prefecture) Stone powder, screenings (Kuzu, Tochigi prefecture) Asphalt emulsion: Noazole (Nichireki Co., Ltd.) Evaporation residue 60.0% by weight Penetration in evaporation residue (25 ° C.) 108 (1/10 mm) Hydraulic inorganic material: Ultra-rapid curing cement (Sumitomo Osaka Cement Co., Ltd.) ) Thermoplastic polymer: Acrylic acid / styrene copolymer resin Solid content 50% by weight Modified asphalt: Polyphalt (Nichireki Co., Ltd.)

The materials used to construct the surface layer are as follows. Thermoplastic polymer: Acrylic copolymer resin emulsion Asphalt emulsion: Cathisol GM (asphalt emulsion with rubber) (manufactured by Nichireki Co., Ltd.) Evaporation residue 51% by weight Penetration degree at evaporation residue (25 ° C.) 87 ( 1/10 mm) Softening point 50 ℃ Fine sand: Kinugawa from Tochigi

Using the above materials, four types of asphalt mixtures A, B, C and D were produced. Tables 1, 2, and 3 show the mixing ratios of the aggregates, the aggregate particle sizes, and the mixing ratios of the respective asphalt mixtures used in the production of the four types of asphalt mixtures.

[0071]

[Table 1]

[0072]

[Table 2]

[0073]

[Table 3]

As is clear from Table 3, the asphalt mixtures A, B and C are room temperature asphalt mixtures using an asphalt emulsion.
Is a mixture of the asphalt emulsion and the aggregate in a state where the volume is increased by whipping the asphalt emulsion, whereas the asphalt mixture C is different in that the asphalt emulsion is not whipped. As the asphalt emulsion whose volume was increased by foaming, an asphalt emulsion whose volume was increased to 5 times the original volume was used. The asphalt mixture B is different from the asphalt mixture A in that the mixture contains a thermoplastic polymer. The asphalt mixture D is a heating type asphalt mixture using modified asphalt.

The procedure for mixing the asphalt emulsion with the aggregate and other materials is as follows: first, the coarse aggregate and the asphalt emulsion are mixed, and then the fine aggregate or filler is added. A hard inorganic material and a thermoplastic high molecular weight polymer were added, and the mixture was further stirred and mixed. When using a heating type asphalt, first, after coarsely aggregating coarse aggregate and fine aggregate or filler,
This was done by adding the heated asphalt and mixing by stirring. The production of the room temperature asphalt mixture of A, B and C was carried out by adding water to 100 parts by weight of the mixture so that the water content was 5.3 parts by weight, including the water content in the asphalt emulsion. .

<Specimen> The specimen was 300 mm × 300 mm.
The asphalt mixture of A to D is placed in a mold frame of mm × 50 mm, and the linear pressure during compaction is set to 30 kgf / cm.
It was manufactured by compacting with a roller compactor. In constructing the surface layer of the present invention, before compaction by a roller compactor, the thermoplastic polymer is sprayed at a rate of 0.5 kg / m ² (0.1% in terms of solid content).
15 kg / m ² ) and sprinkled into the asphalt mixture. For comparison, instead of the surface layer of the present invention,
After compaction by a roller compactor, asphalt emulsion and fine sand were sprayed to produce a test piece having a normal seal coat. The amounts of asphalt emulsion and fine sand scattered during the application of the seal coat were 0.8 liter / m ² and 0.4 m ³ / m ² , respectively. The test specimens prepared using the asphalt mixture at room temperature were cured at room temperature for 7 days, those using the heated asphalt mixture were cured at room temperature for 24 hours, and then both were cured at the test temperature (60 ° C.) for 5 hours. In addition, three specimens were prepared for each sample, and the test results were averaged.

<Test Method> Diameter 15 cm, wheel width 5
cm test wheel with a ground pressure of 6.4 kgf / cm ²
Then, the pedestal was rotated at a speed of 10.5 times / min so that the test wheel drawn a circle having a radius of 10 cm on the specimen in this state. The amount of deformation of the test piece on the test wheel running part was measured, and SDS = (t × c)
The stationary stability (SDS) (times / mm) was determined based on the formula: / d. In the above formula, t: measurement time (minute), c: pedestal rotation speed (10.5 times / minute), d: t
The specimen deformation amount (mm) per minute. The test temperature was 60 ° C. and the test time was 60 minutes. In this SDS test, since the test wheel rotates and moves on the test piece in a circle, the resistance of the test piece to the torsional load can be observed. Table 4 shows the test results.

[0078]

[Table 4]

As is evident from the results in Table 4, the specimens (3) and (3) in which the surface layer was formed by spraying the thermoplastic polymer and infiltrating it into the asphalt mixture at room temperature, and then compacting it. 6) has a higher SDS than that of a conventional test piece coated with a seal coat or other test pieces,
It turns out that it has excellent resistance to twisting. Also, comparing the results of the test specimens (3) and (6),
It can be seen that the twist resistance is further increased by adding a thermoplastic polymer separately to the room temperature asphalt mixture. Further, similarly, even for a specimen in which a surface layer was formed by spraying a thermoplastic polymer, the SDS value was low in a specimen (9) which did not use an asphalt emulsion whose volume was increased by foaming. It can be seen that it is necessary to mix the asphalt emulsion with the aggregate in a state where the volume is increased by foaming in order to improve the twist resistance.

[0080]

As described above, according to the present invention, a thermoplastic polymer is supplied before compaction of a room temperature asphalt mixture, and the thermoplastic polymer is penetrated into the room temperature asphalt mixture and cured. As a result, a strong surface layer integrated with the room temperature asphalt mixture is formed, so that a pavement structure for an airport pavement having excellent twist resistance can be constructed. Moreover, the production of the cold asphalt mixture of the present invention comprises the step of mixing the asphalt emulsion and the aggregate,
As the asphalt emulsion is performed in a state where the volume is increased by foaming, the surface of the aggregate to be used can be uniformly covered with the asphalt film, and the early strength development is achieved in combination with the action of the added hydraulic inorganic material. Thus, not only can the pavement structure be put to practical use in a short time after construction, but also a pavement body having excellent durability can be obtained. The pavement structure of the present invention has less drying shrinkage, has a stress relaxation effect, and does not need to provide joints.
Further twist resistance can be realized by adding a thermoplastic polymer separately to the used asphalt mixture at room temperature. Further, according to the construction method of the present invention, since the room-temperature asphalt mixture is used, the room-temperature construction is possible, and it is possible to save energy and use unnecessary C.
It does not emit O ₂ , and is environmentally friendly. As described above, the present invention has various excellent effects, and is an industrially extremely useful invention.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yutaka Ando 585 Tomimachi, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. In the Construction Materials Division (72) Inventor Kazuhisa Takayama 585 Tomimachi, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. 7-2-1 Garden Heights Joto, 7-2-1 Joto, Koyama City, Tochigi Prefecture 72-72 Inventor Tetsuya Makita 110-2 Koganei, Kokubunji-cho, Shimotsuga-gun, Tochigi Nichireki Koganei Dormitory B-205

Claims (13)

[Claims] 1. A room temperature asphalt mixture containing an aggregate, an asphalt emulsion mixed with the aggregate in a state where the volume is increased by foaming, and a hydraulic inorganic material is paved, and after paving, a hot asphalt mixture is placed on the room temperature asphalt mixture. A method for constructing a pavement structure for an airport pavement in which a plastic polymer is supplied and rolled to form a surface layer integrated with the paved room temperature asphalt mixture. 2. An aggregate comprising coarse aggregate and fine aggregate, wherein the mixture of aggregate and asphalt emulsion comprises fine aggregate and coarse aggregate,
The method for constructing a pavement structure for an airport pavement according to claim 1, wherein the asphalt emulsion whose volume has been increased by foaming is separately mixed, and then mixed with each other. 3. The method of claim 1, wherein the aggregate comprises coarse aggregate and fine aggregate, and the mixing of the aggregate and the asphalt emulsion comprises mixing the coarse aggregate with an asphalt emulsion having an increased volume by bubbling. And adding the asphalt emulsion whose volume has been increased by bubbling and further mixing.
The construction method of the pavement structure for airport pavement as described in the above. 4. The airport according to claim 1, wherein the cold asphalt mixture is produced by mixing an aggregate with an asphalt emulsion whose volume has been increased by bubbling, and further mixing a hydraulic inorganic material. Construction method of pavement pavement structure. 5. The pavement construction method for an airport pavement according to claim 1, wherein the room-temperature asphalt mixture further contains a thermoplastic polymer. 6. The thermoplastic polymer contained in the room temperature asphalt mixture and the thermoplastic polymer supplied after paving the room temperature asphalt mixture are the same substance. Or the construction method of the pavement structure for airport pavement according to 5. 7. The airport pavement according to claim 1, wherein the thermoplastic polymer is supplied as a latex, an emulsion or an aqueous solution obtained by diluting the latex, the emulsion or the emulsion. How to build a pavement structure. 8. The amount of the thermoplastic high molecular weight polymer supplied onto the room temperature asphalt mixture is from 0.1 to 0.1 in terms of solids.
Claim 1, 2, 3, 4, which is in the range of 0.5 kg / m ² .
The construction method of a pavement structure for an airport pavement according to 5, 6, or 7. 9. A pavement constructed from a cold asphalt mixture containing an aggregate, an asphalt emulsion mixed with the aggregate in a state where the volume has been increased by bubbling, and a hydraulic inorganic material; A pavement structure for an airport pavement, comprising a surface layer integrated with the pavement body by permeation of a thermoplastic polymer. 10. The pavement structure for an airport pavement according to claim 9, wherein the surface layer is integrated with the pavement by a part of the thermoplastic high molecular weight polymer penetrating into the pavement. 11. The pavement structure for an airport pavement according to claim 9, wherein the surface layer is integrated with the pavement by permeating the entire amount of the thermoplastic polymer into the pavement. 12. The pavement structure for an airport pavement according to claim 9, wherein the room-temperature asphalt mixture further contains a thermoplastic polymer. 13. The pavement structure for an airport pavement according to claim 12, wherein the thermoplastic polymer contained in the room temperature asphalt mixture and the thermoplastic polymer forming the surface layer are the same substance.