JP2002081003A - Cover material for underside of sleeper for steel bridge and its method of application - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover material for the underside of a sleeper for a steel bridge being excellent in impact resistance and the effect of damping vibrations, while also having a quick-curing property which allows it to dry and cure quickly, so that it is excellent in construction workability and effective in reducing labor and construction cost; a method of applying the material; and a steel bridge using the method. SOLUTION: The cover material covers the top surface of a steel girder which abuts against sleepers laid on top of a steel bridge. The cover material is made from a resin composition containing at least one kind of hardenable resin selected from the group consisting of polyurethane, polyurethaneurea, and polyurea. The method of applying the material is also disclosed. A method of constructing a steel bridge using the method is also disclosed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sleeper undercoating material for a steel bridge, a method of constructing the material, and a steel bridge formed by the method.

[0002]

2. Description of the Related Art In a railway track of a steel bridge with a trackless steel girder structure, a sleeper is laid on a steel girder, and a load from a rail is dispersed throughout the bridge. In this railroad track, in particular, in the railroad track of an existing steel bridge, for example, as shown in FIG. 2, rails 20a and 20b are placed on the left and right upper surfaces of a sleeper, and a sleeper 21a holding the rails 20a and 20b. , 21b, 21c are arranged on the iron girders 22a, 22b, and the upper flanges 23a,
It is fastened to 23b by a hook bolt (not shown) or the like.

[0003] In the steel girder of this steel bridge, the portions that come into contact with the sleepers (23a and 23b in FIG. 2) are repeatedly subjected to an impact load from the sleepers pressed by the train passing on the rails, and In severe cases, such as wear of the coating film and corrosion and wear of the iron, as shown in FIG. 3, a recess 24 may be formed at a place where the sleeper comes into contact. The formation of such a concave portion may cause a reduction in the strength of the steel girder, a crack, or the like, and may cause a replacement of a bridge or, in extreme cases, an accident. further,
The sleeper sinks, the rail cannot be supported at a predetermined height by the sleeper, and vibration and noise are generated when passing through the train.

[0004] Therefore, conventionally, regular repairs have been made,
Complicated work such as shifting the place where the sleeper is laid or replacing the sleeper requires a large number of personnel and costs. Therefore, in recent years, the upper flange of an iron girder is made of an epoxy resin, a vinyl ester resin or a polyester resin, and a lining having a shock resistance and abrasion resistance using a coating material made of a resin composition in which flaky glass flakes are blended. Has been attempted. Since this coating material forms a coating film having excellent corrosion resistance, impact resistance and abrasion resistance, it is effective as a material for coating a portion of the steel girder in contact with the sleeper.

However, this coating material containing glass flakes requires a long time, for example, about one week, to apply a primer, apply a coating material, and dry and cure a coating film. Therefore, when installing on the steel girder of the existing steel bridge operated by the train, the workability during construction is inferior, such as requiring a long construction period in consideration of the time required for drying and hardening,
It was disadvantageous for labor saving and construction cost reduction.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide excellent workability because it has excellent impact resistance and vibration damping effects, has quick curing properties, and does not require time for drying and curing. Another object of the present invention is to provide a sleeper undercoat material for steel bridges that is effective for labor saving and construction cost reduction. Also,
The present invention is capable of applying a coating excellent in impact resistance and vibration damping effect under a sleeper for a steel bridge in a short time and with good workability by using the coating material, thereby saving labor and construction costs. It is an object of the present invention to provide a method capable of reducing the number of steel bridges and a steel bridge by the construction method.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above problems, polyurethane, polyurethane urea,
By using a resin composition containing at least one kind of curable resin selected from polyurea, it was found that a coating layer having excellent impact resistance and vibration damping effect can be obtained with good workability. I came to the invention.

That is, the present invention relates to a coating material for coating an upper surface of a steel girder which is in contact with a sleeper laid on a steel bridge, wherein the coating material comprises at least one curable material selected from polyurethane, polyurethane urea and polyurea. An object of the present invention is to provide a sleeper undercoat material for a steel bridge made of a resin composition containing a resin. In the steel bridge sleeper undercoating material,
Touch drying time specified in JIS K5400 is 20 ° C
Is preferably 2 to 1000 seconds.

[0009] In the steel bridge sleeper undercoating material,
A dumbbell-shaped No. 3 test piece specified in JIS K6251 has a tensile strength of 6 MPa or more and an elongation at break of 200.
% Or more, and the time until the tear strength of the test piece (c) specified in JIS K6252 becomes 30 N / mm or more is preferably 5 to 300 minutes.

[0010] Further, from a height of 500 mm using a DuPont type impact tester specified in JIS K5400, the mass 1
It is preferable that the number of repetitions until the coating film breaks in an impact test performed by repeatedly dropping a kg weight to the same position on the coating film is 5 or more.

Further, it is preferable to have a vibration damping effect of 5 dB or more in a frequency band of 2000 Hz or more.

[0012] The present invention also provides a coating material comprising a resin composition containing at least one curable resin selected from polyurethane, polyurethane urea, and polyurea, in contact with a sleeper laid on a steel bridge. An object of the present invention is to provide a method of applying a sleeper under-covering material for a steel bridge, comprising a step of forming a coating layer by applying the coating to the upper surface of a steel girder.

Further, the present invention provides a steel bridge having a railway track constructed by the above method.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The underlaying material for a sleeper for a steel bridge of the present invention (hereinafter referred to as the "covering material of the present invention") and a method of applying the same will be described in detail below. The coating material of the present invention covers the upper surface of an iron girder that is in contact with a sleeper laid on a steel bridge, and may cover the entire upper surface of the iron girder of the steel bridge, or The upper surface of the spar may be covered only at the place where the sleeper abuts.

[0015] The coating material of the present invention comprises at least one selected from polyurethane, polyurethaneurea and polyurea.
It is made of a resin composition containing a kind of curable resin.
The resin composition contains the above-mentioned curable resin alone or in combination of two or more.
It may include a combination of more than one kind.

The polyurethane used is a reaction solution containing an isocyanate prepolymer having an isocyanate residue and a reaction solution containing a polyol in the presence of a catalyst.
It is manufactured by reacting liquids.

The polyurethane urea is prepared by reacting a reaction solution containing an isocyanate prepolymer having an isocyanate residue with a reaction solution containing a polyol containing a polyamine as a chain extender in the presence of a catalyst. It is manufactured. In addition, polyurea
It is produced by reacting a reaction solution containing an isocyanate prepolymer having an isocyanate residue with a reaction solution containing a polyamine.

The isocyanate prepolymer having an isocyanate residue used for forming a film made of polyurethane, polyurethane urea or polyurea is a reaction product of a polyisocyanate and an active hydrogen-containing compound, and has an isocyanate group in one molecule. Is a prepolymer having at least one. The isocyanate prepolymer may contain a polyisocyanate monomer that has not reacted with the active hydrogen-containing compound.

The polyisocyanate is not particularly limited. Examples of the aromatic polyisocyanate include 2,4
-Tolylene diisocyanate, 2,6-toluene diisocyanate, 1-chloro-2,4-phenylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmenthane diisocyanate, 2,4'-diphenylmethane diisocyanate, 3,3'-dimethyl-4,4'-biphenylenediisocyanate, 3,3'-dimethyl-4,4 '
-Diphenylmenthane diisocyanate, 3,3'-dimethoxy-4,4'-biphenylenediisocyanate,
2,2 ′, 5,5′-tetramethyl-4,4′-biphenylenediisocyanate, polymethylene polyphenylisocyanate, 1,5-naphthalenediisocyanate and derivatives thereof such as dimers, isocyanurates and carbodiimides No. As the aliphatic polyisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmenthane diisocyanate, lysine diisocyanate,
Tetramethylxylene diisocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, trimethylhexa Methylene diisocyanate,
Derivatives such as norbornene diisocyanate and their isocyanurates are included.

Among these, diphenylmethane diisocyanate such as 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, xylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, and isocyanurate-modified xylylene diisocyanate The isomer, isocyanurate-modified isophorone diisocyanate, isocyanurate-modified norbornene diisocyanate, and isocyanurate-modified hexamethylene diisocyanate are preferable because of their low vapor pressure and appropriate reactivity. These polyisocyanates may be used alone or in combination.
A mixture of more than one species can be used.

The active hydrogen-containing compound is not particularly limited, but includes polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin, and trimethylolpropane; polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; Polyester polyols such as polyethylene adipate glycol, polyethylene propylene adipate glycol, polybutylene adipate glycol, polyhexamethylene adipate glycol, polycaprolactone glycol, acrylic polyol,
Examples thereof include polyols such as phenolic resin polyol, epoxy polyol, polybutadiene polyol, polyester-polyether polyol, polycarbonate polyol, and vegetable oil. Also, ethylene glycol,
Polyhydric alcohols such as propylene glycol and trimethylolpropane are used as polymerization initiators and lower alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide or mixtures thereof are reacted. And a polyether polyamine obtained by the reaction. Examples of the polyether polyamine include diamines having an average molecular weight of 200 to 4100 and trimethylolpropane obtained by a reductive amination reaction of a hydroxyl group bonded to a terminal secondary carbon of polypropylene glycol using ethylene glycol or propylene glycol as an initiator. Alternatively, a triamine having an average molecular weight of 400 to 5500 obtained by a reductive amination reaction of a hydroxyl group bonded to a terminal secondary carbon of polypropylene triol using glycerin as an initiator is exemplified.

These polyols or polyether polyamines can be used alone or in combination of two or more. Among these polyols, polyether polyols and polyester polyols are preferred in that the viscosity of the isocyanate prepolymer can be reduced.

Polyols used for producing polyurethane or polyurethane urea include the above-mentioned polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin and trimethylolpropane, and polyhydric alcohols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol. Ether polyols, polyethylene adipate glycol, polyethylene propylene adipate glycol, polybutylene adipate glycol, polyhexamethylene adipate glycol,
Examples thereof include polyester polyols such as polycaprolactone glycol, acrylic polyol, phenolic resin polyol, epoxy polyol, polybutadiene polyol, polyester-polyether polyol, polycarbonate polyol, and vegetable oil. These polyols can be used alone or in combination of two or more.

Examples of the chain extender used in the production of polyurethane include ethylene glycol and 1,4
-Butane glycol, hydroquinone diethylol ether, 2,3-butane glycol and the like.

Examples of the chain extender for polyurethane urea include 3,3'-dichloro-4,4'-diaminodiphenylmethane, a condensate of 2-chloroaniline, aniline and formaldehyde, 4,4'-diaminodiphenyl, 4,4'-diaminodiphenyl ether, 2,3-
Diaminotoluene, 3,4-diaminotoluene, 2,4
-Diaminotoluene, 2,6-diaminotoluene, 4,
4'-diaminodiphenylmethane, 2,4-diaminodiphenylmethane, 1,3-phenylenediamine, 1,4
-Phenylenediamine, naphthylene-1,5-diamine, aniline-formaldehyde condensate, 1,3-dimethyl-2,4-diaminobenzene, 1,3-dimethyl-
2,5-diaminobenzene, 1,3-diethyl-2,4
-Diaminobenzene, 1,3-diethyl-2,5-diaminobenzene, 1,4-diisopropyl-2,5-diaminobenzene, 2,4-diaminomesitylene, 1,3
5-triethyl-2,4-diaminobenzene, 1,3
5-triethyl-2,6-diaminobenzene, 1,3
5-triisopropyl-2,4-diaminobenzene,
1,3,5-triisopropyl-2,6-diaminobenzene, 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-
Diaminobenzene, 2,3-dimethyl-1,4-diaminonaphthalene, 2,6-dimethyl-1,5-diaminonaphthalene, 2,6-diisopropyl-1,5-diaminonaphthalene, 2,6-dibutyl-1, 5-diaminonaphthalene, 3,3 ', 5,5'-tetraisopropyl-benzidine, 3,3', 5,5'-tetramethyl-4,
4'-diaminodiphenylmethane, 3,3 ', 5,5'
-Tetraethyl-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetraisopropyl-4,
4'-diaminodiphenylmethane, 3,3 ', 5,5'
-Tetrabutyl-4,4'-diaminodiphenylmethane, 3,5-diethyl-3'-methyl-2 ', 4-diaminodiphenylmethane, 3,3'-diethyl-4,4'
-Diaminodiphenylmethane, 3,3'-diethyl-
2,2′-diaminodiphenylmethane, 3,3 ′, 5
5'-tetraethyl-4,4'-diaminodiphenyl ether, 3,3 ', 5,5'-tetraisopropyl-
4,4'-diaminodiphenyl ether, tert-butyltoluenediamine, 1,3,5-triisopropyl-2,4-diaminobenzene, 4,4'-bis (sec
-Butylamino) diphenylmethane, 1,4- (sec
-Butylamino) benzene, trimethylene oxide-
Amino group-containing compounds such as polytetramethylene oxide-di-p-aminobenzoates such as di-p-aminobenzoate and tetramethylene oxide-di-p-aminobenzoate. In addition, ethylene glycol, polyhydric alcohols such as trimethylolpropane as a polymerization initiator, ethylene oxide, propylene oxide,
A polyetherpolyamine obtained by substituting a terminal hydroxyl group of a polyether polyol obtained by reacting a lower alkylene oxide such as butylene oxide or a mixture thereof with an amino group, specifically, ethylene glycol or propylene glycol as an initiator To a terminal secondary carbon of polypropylene triol with an initiator of diamine, trimethylolpropane or glycerin having an average molecular weight of 200 to 4100 obtained by reductive amination reaction of a hydroxyl group bonded to the terminal secondary carbon of polypropylene glycol Average molecular weight 400 to 5 obtained by reductive amination reaction of hydroxyl group
And 500 triamines. These amines can be used alone or in combination of two or more.

Examples of the catalyst used for producing polyurethane or polyurethane urea include organic metal compounds such as fatty acid salts such as tin, lead, bismuth and zinc, and organic acids. As the organometallic compound, lead and bismuth are preferable in terms of preventing foaming, and the amounts used are the raw materials used (polyol component and isocyanate prepolymer component).
Is suitably 0.01 to 5% based on the total amount of

Organic acids include COOH groups, SO ₃ H
It is a compound having at least one acidic group such as a phenolic OH group or a phenolic OH group in the molecule, and is preferably a fatty acid, oxycarboxylic acid, nonylphenol or the like. The amount of the organic acid used is suitably from 0.01 to 5% based on the total amount of the raw materials (the polyol component and the isocyanate prepolymer component).

Examples of the polyamine used for producing polyurea include 3,3'-dichloro-4,4'-diaminodiphenylmethane, a condensate of 2-chloroaniline, aniline and formaldehyde, and 4,4'-diaminodiphenyl. , 4,4'-diaminodiphenyl ether,
2,3-diaminotoluene, 3,4-diaminotoluene, 2,4-diaminotoluene, 2,6-diaminotoluene, 4,4′-diaminodiphenylmethane, 2,4-
Diaminodiphenylmethane, 1,3-phenylenediamine, 1,4-phenylenediamine, naphthylene-1,5
-Diamine, aniline-formaldehyde condensate, 1,
3-dimethyl-2,4-diaminobenzene, 1,3-dimethyl-2,5-diaminobenzene, 1,3-diethyl-2,4-diaminobenzene, 1,3-diethyl-2,
5-diaminobenzene, 1,4-diisopropyl-2,
5-diaminobenzene, 2,4-diaminomesitylene,
1,3,5-triethyl-2,4-diaminobenzene,
1,3,5-triethyl-2,6-diaminobenzene,
1,3,5-triisopropyl-2,4-diaminobenzene, 1,3,5-triisopropyl-2,6-diaminobenzene, 1-methyl-3,5-diethyl-2,4-
Diaminobenzene, 1-methyl-3,5-diethyl-
2,6-diaminobenzene, 2,3-dimethyl-1,4
-Diaminonaphthalene, 2,6-dimethyl-1,5-diaminonaphthalene, 2,6-diisopropyl-1,5-
Diaminonaphthalene, 2,6-dibutyl-1,5-diaminonaphthalene, 3,3 ′, 5,5′-tetraisopropyl-benzidine, 3,3 ′, 5,5′-tetramethyl-4,4′-diamino Diphenylmethane, 3,3 ',
5,5'-tetraethyl-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetraisopropyl-
4,4′-diaminodiphenylmethane, 3,3 ′, 5
5′-tetrabutyl-4,4′-diaminodiphenylmethane, 3,5-diethyl-3′-methyl-2 ′, 4-diaminodiphenylmethane, 3,3′-diethyl-4,
4′-diaminodiphenylmethane, 3,3′-diethyl-2,2′-diaminodiphenylmethane, 3,3 ′,
5,5'-tetraethyl-4,4'-diaminodiphenyl ether, 3,3 ', 5,5'-tetraisopropyl-4,4'-diaminodiphenyl ether, tert-
Butyltoluenediamine, 1,3,5-triisopropyl-2,4-diaminobenzene, 4,4′-bis (se
c-butylamino) diphenylmethane, 1,4- (se
and polytetramethylene oxide-di-p-aminobenzoates such as c-butylamino) benzene, trimethylene oxide-di-p-aminobenzoate, and tetramethylene oxide-di-p-aminobenzoate. Also, a polyhydric alcohol such as ethylene glycol or trimethylolpropane is used as a polymerization initiator, and a terminal alkyl group of a polyether polyol obtained by reacting a lower alkylene oxide such as ethylene oxide, propylene oxide or butylene oxide or a mixture thereof is converted to an amino group. And more specifically, an average molecular weight of 200 to 200 obtained by a reductive amination reaction of a hydroxyl group bonded to a terminal secondary carbon of polypropylene glycol using ethylene glycol as an initiator. 4100 diamines,
Average molecular weight of 400 to 5 obtained by reductive amination reaction of hydroxyl group bonded to terminal secondary carbon of polypropylene triol using trimethylolpropane as an initiator
And 500 triamines. These amines can be used alone or in combination of two or more.

The resin composition used as the coating material of the present invention is a composite of the above resin component and fibers, woven fabric, nonwoven fabric, etc. for the purpose of preventing deformation, reinforcing and improving the durability of the resulting film. It may be. The material of these fibers, woven fabric and non-woven fabric is not particularly limited, for example, natural fibers such as cotton, hemp, pulp fibers, acrylic, synthetic fibers such as polyester, carbon fibers, glass fibers, metal fibers, and the like. One type or two or more types may be used in combination depending on the purpose.

The resin composition used as the coating material of the present invention may contain a plasticizer, a flame retardant, an antifoaming agent, a coloring agent, a stabilizer, a filler, a coupling agent, a modifier, etc., if necessary. Can be added. Examples of the plasticizer include phthalic esters such as dioctyl phthalate, adipic esters such as dioctyl adipate, tricresyl phosphate, and chlorinated paraffin.

As the flame retardant, for example, tris- (β-
(Chloropropyl) phosphate, tris-dichloropropyl phosphate, tris-chloroethyl phosphate, and other phosphoric acid esters; and dibromoneopentyl glycol, tribromoneopentyl alcohol, and other bromine-containing compounds. Examples of the coloring agent include carbon black, red iron oxide, titanium dioxide, phthalocyanine green, and phthalocyanine blue.

Examples of the stabilizer include hindered phenols such as Irganox # 1010 (trade name, manufactured by Ciba Geigy), Yoshinox BHT, BB, GSY-930 (trade name, manufactured by Yoshino Pharmaceutical Co., Ltd.), and Tinuvin P, 327, 328.
Benzotriazoles such as (manufactured by Ciba-Geigy), benzophenones such as Tomisorp 800 (manufactured by Yoshino Pharmaceutical),
Sterically hindered amines such as SANOL LS-770, 744, Tinuvin 144 (manufactured by Ciba Geigy) and the like. Examples of the filler include kaolin, diatomaceous earth, silica powder, talc, calcium carbonate, perlite, vermiculite, and barium sulfate.

Next, a method of applying a coating under a sleeper of an existing steel bridge using the coating material of the present invention will be described with reference to an example of the application to a steel bridge shown in FIG. First, in the steel bridge shown in FIG. 2, the rails 20a and 20b and the sleepers 21a, 21b and 21c are disengaged, and the hook bolts (not shown) and the like are removed.
Upper flanges 23a and 23b of iron girders 22a and 22b,
The fastening with the sleepers 21a, 21b, 21c is released.
Next, the laying position of the sleepers 21a, 21b, 21c is shifted from the current position or removed, and if necessary, a temporary support for holding the rails 20a and 20b is laid at an adjacent position.

The upper and side surfaces of the upper flanges 23a and 23b of the iron girders where the sleepers 21a, 21b and 21c were laid are formed on the upper and side surfaces of the steel girder to remove deposits and corrosion products and to form a coating film. Leveling. Next, after applying a primer if necessary, the coating material of the present invention is applied to form a coating 3 having a predetermined thickness on the upper surface and side surfaces of the upper flange 2 of the iron beam 1 as shown in FIG. . Cure the coating and confirm that the coating has reached the specified hardness. Finally, the sleepers 21a, 21b, and 21c are sequentially placed on the iron girder 22.
a, 22b are arranged on the coating 1 formed on the
a, 22b are fastened to the upper flanges 23a, 23b by hook bolts (not shown) or the like.
0a and 20b are placed on the rails 20a and 20b.
And sleepers 21a, 21b, 21c.

In the method of the present invention, the coating material of the present invention is applied to other parts of the steel girders as necessary.
A coating excellent in weather resistance, salt water resistance, corrosion resistance, especially acid resistance can be formed, and the durability of a steel bridge can be improved. Furthermore, since the coating obtained using the coating material of the present invention is a viscous substance as compared with an epoxy resin, an unsaturated polyester resin, a vinyl ester resin, and the like, it is effective in improving vibration damping properties, and it is effective in improving the steel bridge. It reduces noise caused by the vibration of passing trains, and is particularly effective in reducing noise.

The method of applying the coating material of the present invention to the upper surface of an iron girder may be appropriately selected according to the structure, shape, construction form, etc. of the girder to be applied. For example, application by static mixer mixing / discharge or collision mixing type spray application is selected.

The thickness of the coating formed by the coating material of the present invention is appropriately selected depending on the exposure environment of the steel girder to be applied and the degree of wear. Usually, it is about 0.1 to 5 mm, and 2
A range of 範 囲 5 mm is preferred.

The primers used as necessary include, for example, a solvent type two-component epoxy, a solventless type
Liquid-mixed epoxy, moisture-curable urethane, solvent-type two-component urethane, solvent-free two-component urethane, solvent-free two-component urethane urea, and the like.

The coating material of the present invention is usually used at 20 ° C. for 2 to 2 hours.
It indicates a touch drying time of 1000 seconds, and after a coating by a two-liquid discharging device equipped with a static mixer or a special spray system including a spray gun equipped with a collision mixing component, the next coating plant is completed in a very short time. It has the advantage of being able to move to places.

The coating material of the present invention is usually used at 20 ° C.
With a curing time of 5 to 300 minutes, the tensile strength measured by a tensile test using a No. 3 dumbbell-shaped test piece specified in JIS K6251 exceeds 6 MPa, and the elongation at break exceeds 200%. Further, the tear strength measured by a tear test using the test piece (c) specified in JIS K6252 is 30 N /
mm. These touch dry time, tensile strength and tear strength are necessary for restoring the sleeper by displacing or pushing it into the coated surface, and it is necessary to put it in service. You can reach that state quickly. Therefore, it is effective in shortening the construction period, saving labor, and reducing construction costs when constructing a film under a sleeper of an iron girder of a steel bridge.

[0041]

EXAMPLES The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The evaluation of impact resistance, salt water resistance and vibration damping effect in the following examples and comparative examples was performed according to the following methods.

Evaluation of Impact Resistance Referring to the test method using a DuPont impact tester specified in JIS K5400, a 500 mm
A weight of 1000 g was repeatedly dropped from the height of the sample to the same position, and the presence or absence of cracks in the coating film was visually inspected, and the number of repetitions until cracks were formed was determined as an index of impact resistance.

Evaluation of salt water resistance Handbook for surface protection of concrete structures (draft) and commentary Appendix I, Test Method 8 Salt barrier test (May 1989, edited by Hanshin Expressway Public Corporation, Japan Society for Materials Science) Performed in compliance.

Evaluation of Vibration Attenuation Effect One end of a 100 × 90 mm test piece was fixed, a microphone was set at a position 300 mm away from the test piece, and a vibration measuring device was set at a point 20 × 50 mm from the end of the test piece. After that, a steel ball having a mass of 8.3 g was naturally dropped on the coated surface from a height of 200 mm, and a vibration damping effect at the time of collision was evaluated.

Example 1 Preparation of a Reaction Solution Preparation of a Reaction Solution for Polyurethane In a reaction vessel, 4,4′-diphenylmethane diisocyanate (having an isocyanate group content of 33.3%) was placed under a nitrogen gas atmosphere.
6%) 100 parts by weight, carbodiimide-modified diphenylmethane diisocyanate (isocyanate group content 29%)
49.9 parts by weight and 85.45 parts by weight of polypropylene glycol having an average molecular weight of 3000 were added, and reacted at 80 ° C. for 8 hours with vigorous stirring to obtain a reaction solution containing an isocyanate prepolymer having an isocyanate residue (hereinafter, referred to as “ Reaction solution A ") was prepared.

Further, based on 100 parts by weight of polypropylene glycol having an average molecular weight of 2000, 26.7 parts by weight of 1,4-butanediol, 2 parts by weight of bismuth trinedecanoate as a catalyst, and 6 parts by weight of a toner and an additive were used. The mixture was added and mixed to prepare a polyol reaction liquid (hereinafter, referred to as “reaction liquid B”).

The prepared reaction solution A and reaction solution B were supplied from each storage tank via a drum pump via proportioner H-2.
000 (manufactured by Gasmer) at a discharge pressure of 10 MPa, a discharge ratio (volume ratio) of two liquids = 1: 1, and a spray gun (Gasmer) through a hot hose controlled to 70 ° C and heated to 70 ° C. GX-7), which are mixed and reacted in a spray gun, sprayed in mist, deposited on a substrate, and cured to form a polyurethane film.

Formation of Polyurethane Urea Coating Rim Spray F-1000 (Mitsui Toatsu) which is a stock solution of polyurethane urea comprising an isocyanate prepolymer solution having an isocyanate residue and a mixture of polyol, polyamine, catalyst, toner and additives. (Manufactured by Construction Materials Co., Ltd.), and a polyurethane urea film is formed in the same manner as the polyurethane film.

Formation of polyurea film: isocyanate prepolymer solution having isocyanate residue, toner,
Using a polyurea AR-200 (manufactured by Sun Techno Chemical Co., Ltd.) which is a stock solution of polyurea comprising a polyamine solution containing an additive, a polyurea film is formed in the same manner as in the preparation of a polyurethane film. In accordance with the above coating method, a test piece was prepared by the following method, and the tensile strength, elongation at break, tear strength, and available service time were measured, and the impact resistance and vibration damping effect were evaluated. went. The results are shown in Tables 1 and 2.

(1) A polypropylene plate (500 × 500)
A film having a thickness of 2 mm was formed on the surface of (× 10 mm) according to the method described above, and the touch dry time was immediately measured by the method specified in JIS K5400. Next, 30 minutes, 1 hour, 2 hours, 3 hours, and 6 hours after forming the coating, JIS K6251 and JIS K6252.
The tensile strength, the elongation at break, and the tear strength, as defined in, were measured, and the serviceable time was examined. Further, a sheet-shaped test piece cut into a predetermined shape was subjected to a salt barrier test.

(2) Moisture-curable urethane (P-2080, manufactured by San Techno Chemical Co., Ltd.) is applied to the entire surface of a steel plate (75 × 150 × 3 mm) that has been rust-removed with # 240 water-resistant abrasive paper to a dry film thickness of approximately 50 μm. And left at 20 ° C. Immediately after the moisture-curable urethane was brought into a dry state to the touch in 20 minutes, a coating having a thickness of 2 mm was immediately formed according to the above-described method to prepare a coated test piece. The impact resistance of the obtained test piece was evaluated.

(3) Half of the steel plate (200 × 90 × 3 mm) is rust-removed with a # 240 water-resistant abrasive paper, and the moisture-curable urethane and A coated test piece was prepared according to the method described above. Table 2 shows the results of evaluating the vibration damping effect of the obtained test piece, using a steel sheet not coated with a coating as a comparative example.

[0053]

[Table 1] * Serviceable time: After construction, the longest time out of the time when the tensile strength becomes 6 MPa or more, the time when the elongation at break becomes 200% or more, and the time when the tear strength becomes 30 N / mm or more is the steel bridge. Was set to a time when it became possible to use it.

[0054]

[Table 2] Note Compared to the steel sheet without the coating of the comparative example,
If the vibration level is reduced, it has a vibration damping effect.

[0055]

The underlaying material for sleepers for steel bridges of the present invention is excellent in impact resistance and vibration damping effect, has fast curing properties, and requires no time for drying and curing.
It has excellent workability in a short time, and is effective for labor saving and construction cost reduction. According to the method of the present invention,
By using the coating material, a film with excellent impact resistance and vibration damping effect can be installed under a sleeper for steel bridges in a short time and with good workability, aiming to save labor and reduce construction costs. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating a film formed on an iron girder by a method of the present invention.

FIG. 2 is a perspective view illustrating the arrangement of iron girders and sleepers in a steel bridge.

FIG. 3 is a conceptual diagram illustrating a concave portion of an iron girder formed by a sleeper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Iron girder 2 Upper flange 3 Coating 20a, 20b Rail 21a, 21b, 21c Sleeper 22a, 22b Iron girder 23a, 23b Upper flange 24 Depression

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Makoto Tanaka 2-8-3 Hikaricho, Kokubunji, Tokyo Metropolitan Institute of Technology (72) Inventor Hiroto Machida 2-8-8 Hikaricho, Kokubunji, Tokyo 38 Within the Railway Technical Research Institute (72) Inventor Masanori Hansaka 2-8-8 Hikaricho, Kokubunji-shi, Tokyo 38 Within the Railway Technical Research Institute (72) Takafumi Enari 2--8 Hikaricho, Kokubunji-shi, Tokyo 38 Inside the Railway Technical Research Institute (72) Inventor Hiroshi Iizuka 3 Chigusa Kaigan, Ichihara City, Chiba Prefecture Inside Mitsui Chemicals, Inc. (72) Katsutaro Kauchi 4-5-1-14 Nihonbashi Honcho, Chuo-ku, Tokyo F term in San Techno Chemical Co., Ltd. (reference) 2D056 AA01 AA09 4J038 DG051 DG061 DG111 DG131 DG271 DG281 DG291 NA09 NA23 PB05 PC02 PC 06

Claims (7)

[Claims] 1. A coating material for coating an upper surface of an iron girder to be in contact with a sleeper laid on a steel bridge, comprising a resin containing at least one curable resin selected from polyurethane, polyurethane urea and polyurea. Underlay material for sleepers made of a composition. 2. The under sleeper material for a steel bridge according to claim 1, wherein the touch drying time specified in JIS K5400 is 2 to 1000 seconds at 20 ° C. 3. The tensile strength specified in JIS K6251 is 6 MPa or more, the elongation at break is 200% or more, and JIS
The sleeper undercoating material for steel bridges according to claim 1, wherein the time until the tear strength of the test piece (c) specified in SK6252 becomes 30 N / mm or more is 5 to 300 minutes. 4. A mass of 1 kg from a height of 500 mm using a DuPont impact tester specified in JIS K5400.
The undercoating material for steel bridge sleepers according to any one of claims 1 to 3, wherein the number of repetitions until the coating film is cracked is 5 or more in an impact test performed by repeatedly dropping the weight of the weight at the same position on the coating film. 5. In a frequency band of 2000 Hz or more,
The steel bridge sleeper undercoating material according to any one of claims 1 to 4, which has a vibration damping effect of 5 dB or more. 6. A coating material comprising a resin composition containing at least one kind of curable resin selected from polyurethane, polyurethane urea and polyurea is coated on an upper surface of an iron girder in contact with a sleeper laid on a steel bridge. A method for applying a sleeper under-covering material for a steel bridge, comprising a step of forming a coating layer by applying. 7. A steel bridge having a railway track constructed according to the method of claim 6.