JPH09221919A - Repairing and reinforcing method for existing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the workability by impregnating strengthened fiber sheet having predetermined components stuck with a resin consisting of predetermined components and reinforcing by adhering the sheet to an existing structure and specifying the viscosity of the resin and the layout dimensions of sheet fibers. SOLUTION: A strengthened fiber sheet stuck with a hardening acceleration agent is impregnated with a resin consisting of vinyl-polymerized monomer and/or oligomer having a methacrylate as a main component and a resin consisting of an organic peroxide, and this sheet is adhered to an existing concrete structure for reinforcement. Next, the resin viscosity is set to 5 to 10<4> centipoise at 20 deg.C, and then paraffin wax is added to give air shielding ability, glossiness and contamination resistance. The sheet is, at least on one surface of a sheet consisting of strengthened fibers aligned and arranged in one direction, located at the intervals of 3 to 150mm by laying heat-adhesive fibers along the longitudinal direction of the strengthened fibers in the direction perpendicular to the strengthened fibers. By doing this, the work can be carried out in a short time period without being affected by temperature and environment and also reinforcing effect can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing and reinforcing existing structures made of concrete such as bridge piers, bridges and columns of buildings.

[0002]

2. Description of the Related Art It is widely known that fiber reinforced resin is used for repair and reinforcement of existing structures made of concrete such as bridge piers, bridges and columns of buildings. As one of the methods, there is a so-called unidirectionally aligned sheet material such as carbon fiber, glass fiber, organic fiber or the like, sheet material such as woven fabric or so-called sheet material obtained by previously impregnating an appropriate amount of epoxy resin. While impregnating and replenishing the epoxy resin on site with the prepreg, affixing it to the repair and reinforcement points of the structure,
A method of laminating a plurality of sheets is performed as needed.

[0003]

However, in the above repair / reinforcement method, a room temperature curing type epoxy resin is generally used from the viewpoint of use results and site workability, but it can be said that it is a room temperature curing type. If the temperature is 10 ° C. or lower, particularly 5 ° C. or lower, the curability remarkably decreases and the curing failure tends to occur. Therefore, there is a problem that the curing and curing requires a long period of time and the construction period becomes long. There was also a problem that construction became difficult depending on the time of day and the area. Further, since the hardening is hindered by moisture, it is necessary to sufficiently manage the concrete construction surface and to prepare the groundwork, which makes the construction difficult in rainy weather.

The present invention solves the above problems, has excellent curability at room temperature and low temperature, is excellent in short-term workability, and has an excellent reinforcing effect, such as piers, bridges, and columns of buildings. It is an object to provide a method for repairing and reinforcing existing structures made of concrete.

[0005]

According to the present invention, when a sheet-like material made of reinforcing fibers is impregnated with a resin and the existing structure is repaired and reinforced with a fiber-reinforced resin layer obtained by curing the resin, the following components (1) ) And (2) are used, and the resin is impregnated into a sheet-like material made of reinforced fibers to which the following component (3) has been adhered in advance to start curing, and repair and reinforcement of an existing structure. The above problem is solved by a method. Component (1) At least one vinyl-polymerizable monomer and / or oligomer Component (2) Organic peroxide Component (3) Curing accelerator

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The reinforcing fibers used in the present invention include inorganic fibers such as carbon fibers and glass fibers, organic fibers such as aramid fibers, and other high-strength or highly elastic fibers that are usually used as reinforcing fibers. Is mentioned. Further, a mixture of these reinforcing fibers may be used. Among them, carbon fiber is particularly preferable, the tensile elastic modulus is 20 ton / mm ² or more, and the tensile strength is 300 kg / mm ^2.
The above are more preferred. Most preferably, a carbon fiber surface to which a low molecular weight compound having a radical reactive group is provided.

Examples of the low molecular weight compound having a radical reactive group include acrylic monomers such as acrylic acid, methyl acrylate, ethyl acrylate and butyl acrylate, vinyl monomers such as methacrylic acid and methacrylate monomers such as methyl methacrylate. A relatively low molecular weight homopolymer or copolymer of these monomers can be exemplified, and as a treatment method, a carbon fiber is passed through a solution containing a low molecular weight compound having a radical reactive group and dried. A commonly used method such as
A particularly preferred example is a bisphenol derivative having a (meth) acrylate terminal obtained by reacting a bisphenol-type epoxy resin with acrylic acid or methacrylic acid.

Examples of the sheet-like material made of reinforcing fibers used in the present invention include woven fabrics made of the above-mentioned reinforcing fibers, unidirectionally arranged sheet-like materials, nonwoven fabrics, mats, and combinations thereof. , In particular, a sheet-shaped article made of reinforced fibers obtained by heat-sealing a heat-fusible fiber cloth on at least one surface of a sheet-shaped article made of reinforced fibers aligned in one direction, or reinforced in one direction A heat-fusible fiber is provided on at least one surface of a sheet-shaped article made of fibers in a direction orthogonal to the reinforcing fiber in a range of 3 to 150 along the longitudinal direction of the reinforcing fiber.
A sheet-like material composed of reinforcing fibers arranged at intervals of mm and thermally fused is preferably used.

In the present invention, a resin comprising at least one vinyl-polymerizable monomer and / or oligomer (1) and an organic peroxide (2) is a curing accelerator (3).
Sufficient working time is required to start the curing reaction only by impregnating a sheet-shaped material composed of reinforced fibers with which is attached and contacting or mixing the resin composed of the components (1) and (2) with the component (3). It is necessary from the standpoints of securing the safety and efficiency of work.

Examples of the at least one vinyl-polymerizable monomer as the component (1) include (meth) acrylate, (meth) acrylic acid, styrene, vinyltoluene and vinyl acetate. From the viewpoint of reactivity and weather resistance of the resin after curing, it is preferable to contain (meth) acrylate as a main component. Here, "(meth) acrylate" refers to acrylate and / or methacrylate.

Specific examples include methyl (meth) acrylate, ethyl (meth) acrylate and propyl (meth).
Acrylate, n-butyl (meth) acrylate, t-
Butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
n-nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, Isobornyl (meta)
Acrylate, methoxyethyl (meth) acrylate,
Ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2
-Monofunctional (meth) acrylate monomers such as hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) acrylic acid, (meth) acryloylmorpholine; ethylene glycol di (meth) acrylate, 1,3 -Propylene glycol di (meth) acrylate, 1,4-heptanediol di (meth) acrylate, 1,6-hexanediol (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, tetraethylene Glycol di (meth) acrylate, 2-butyne-1,4-di (meth) acrylate,
Cyclohexane-1,4-dimethanol (meth) acrylate, hydrogenated bisphenol A di (meth) acrylate, 1,5-pentanedi (meth) acrylate, trimethylolethane di (meth) acrylate, tricyclodecane dimethanol di (meth) ) Acrylate, trimethylolpropane di (meth) acrylate, dipropylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 2,2-bis- (4
-(Meth) acryloxypropoxyphenyl) propane, 2,2-bis- (4- (meth) acryloxy (2-
Hydroxypropoxy) phenyl) propane, bis-
Examples thereof include bifunctional (meth) acrylate monomers such as (2- (meth) acryloyloxyethyl) phthalate.

Among the above, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, which has good curability and low viscosity, n
-Butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,3-butylene glycol Di (meth) acrylate is particularly preferred. 1-2 of these
The functional monomer may be used alone or in combination of two or more.

Further, the vinyl-polymerizable at least one oligomer may be an oligomer containing a (meth) acryloyl group and / or an allyl group,
Specifically, polyester poly (meth) acrylate obtained by reacting a polybasic acid such as phthalic acid and adipic acid with a polyhydric alcohol such as ethylene glycol and butanediol, and a polybasic acid such as phthalic acid and adipic acid Allyl group-containing polyester poly (meth) acrylate obtained by reaction of polyhydric alcohols such as ethylene glycol and butanediol with allyl ether group-containing alcohols such as pentaerythritol triallyl ether and trimethylolpropane diallyl ether and (meth) acrylic acid , Phthalic acid, adipic acid and other polybasic acids and ethylene glycol, butanediol and other polyhydric alcohols and pentaerythritol triallyl ether, trimethylolpropane diallyl ether and other allyl ether group-containing alcohols obtained by reaction Group-containing polyester, epoxy poly (meth) acrylate obtained by reaction of epoxy resin and (meth) acrylic acid, obtained by reaction of polyol, polyisocyanate and hydroxyl group-containing monomer such as 2-hydroxyethyl (meth) acrylate. Of urethane poly (meth) acrylates, polyols and polyisocyanates with allyl ether group-containing alcohols such as pentaerythritol triallyl ether and trimethylolpropane diallyl ether and hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate Allyl ether group-containing urethane poly (meth) acrylate, polyol and polyisocyanate, pentaerythritol triallyl ether, trimethylolpropane diallyl ether, etc. Allyl ether group-containing urethanes obtained by reaction of a call and the like.

Further, the component (1) may contain a thermoplastic polymer, and specific examples of the thermoplastic polymer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate and n. -Butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, di Cyclopentanyl (meta)
Acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, Methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate , Homopolymers or copolymers of monofunctional (meth) acrylate monomers such as (meth) acrylic acid and (meth) acryloylmorpholine.

Further, in order to improve various characteristics, various additives such as plasticizers, weathering agents, antistatic agents, lubricants, release agents, dyes, pigments, defoamers, polymerization inhibitors, various kinds. A filler or the like may be added. In particular, the addition of paraffin wax is preferable for the purpose of air blocking action, imparting gloss to the surface of the cured product, and improving stain resistance. In the present invention, the paraffin wax refers to higher fatty acids such as paraffin wax, polyethylene wax, stearic acid and 1,2-hydroxystearic acid.

As the component (1), Acrisilap DR series manufactured by Mitsubishi Rayon Co., Ltd. is commercially available and can be used.

The component (2) may be any as long as it can form a redox catalyst in combination with the component (3), and examples thereof include organic peroxides represented by benzoyl peroxide and methyl ethyl ketone peroxide. In order to avoid handling danger, it is preferable to use a paste or powder of benzoyl peroxide diluted with an inert liquid or solid to a concentration of about 50%.

The viscosity of the resin obtained by mixing these components (1) and (2) is 5 to 10 ⁴ centipoise at 20 ° C., the coatability of the resin, and the resin for the sheet-like material composed of the reinforcing fibers. Is preferable in terms of impregnating property and penetrating property into a concrete structure.

As the component (3), metal soaps such as cobalt naphthenate and cobalt octylate, and aromatics such as dimethyltoluidine, diethyltoluidine, diisopropyltoluidine, dihydroxyethyltoluidine, dimethylaniline, diethylaniline, diisopropylaniline and dihydroxyethylaniline. Group tertiary amines and the like are used alone or in combination of two or more.

In the present invention, it is necessary that the component (3) is previously attached to the sheet-like material composed of the reinforcing fibers. For this reason, a sheet-shaped product may be prepared by previously attaching the component (3) to the reinforcing fiber, or the component (3) may be attached to the sheet-like product made of the reinforcing fiber.

When the component (3) is a solid, its powder may be sprinkled, or it may be dissolved in a suitable solvent and the like, and then reinforced fibers or a sheet-like material composed of reinforced fibers may be passed through this solution. Alternatively, a method of drying and removing the solvent may be used. Further, when the component (3) is a liquid, a method of passing the reinforcing fiber or a sheet-shaped material composed of the reinforcing fiber into the liquid or the solution and drying and removing the solvent can be employed.

In the present invention, as described above, the resin composed of the components (1) and (2) is impregnated into the sheet-shaped material composed of the reinforced fiber to which the component (3) is attached in advance. Impregnation can also be achieved by using ordinary rolls or brush rolls.

Next, a method for repairing and reinforcing an existing structure will be described with reference to a plurality of embodiments, but it goes without saying that the present invention is not limited to these embodiments. In the case of the concrete surface treatment, for example, if there is mortar coating on the repair and reinforcement part of the existing concrete structure, the mortar coating is scraped off to expose the concrete surface, and the concrete surface is ground smoothly using a grinder or the like. The resin is used for the step (1), and the surface is smoothed by filling it with a putty material having good adhesiveness (for example, a putty material comprising the resin composition of the present invention and various fillers).

Embodiment (i) First, a concrete base treatment is carried out, and an acrylic resin primer is applied if necessary. The resin consisting of the components (1) and (2) is applied thereon, and the sheet-like material consisting of the reinforcing fibers to which the component (3) is attached is placed on the resin, impregnated with the resin using a roller, and then at room temperature. Leave it to cure.

Embodiment (ii) First, a concrete base treatment is carried out, and an acrylic resin primer is applied if necessary. A resin comprising the components (1) and (2) is applied thereon, and a sheet-like material comprising the reinforcing fibers to which the component (3) is attached is disposed on the resin, and further the components (1) and (2) are used. Resin is applied, the resin is impregnated with a roller, and the resin is left standing at room temperature to cure.

[0026]

The present invention will be described in more detail with reference to the following examples.

(Example 1) A carbon fiber Pyrofil TR- manufactured by Mitsubishi Rayon Co., Ltd. was used as a sheet made of reinforcing fibers.
30G (12000 filaments) is aligned at 2.5 mm intervals with a width of 300 mm in one direction using a siding plate to form warps, and long glass fibers 450 count and low melting point nylon are provided at intervals of 10 mm in the direction orthogonal to the carbon fiber bundle. Filament 5
After weaving a heat-fusible yarn in which 0 denier is twisted as a weft into a plain weave, it is passed through a heating roller set at a temperature of 90 ° C. and a pressure of 1 kg / cm ² for 40 seconds to give a carbon fiber basis weight of 300 g / m 2. ^A sheet-like material composed of the reinforcing fibers of ² was obtained. An average of 10 g / m of N, N-diisopropyl-p-toluidine powder as component (3) was added to the sheet material.
By coating and coating so as to be ² , a reinforcing fiber sheet 1 having the component (3) attached was obtained.

On the other hand, the resin is prepared by first preparing 60 parts of methyl methacrylate / 2-ethylhexyl acrylate 10 parts.
Parts / 1,3-butylene glycol dimethacrylate 2 parts and n-paraffin as a paraffin wax (melting point 54
1 part of γ-methacryloxypropyltrimethoxysilane as a silane coupling agent,
While mixing this mixture with heating at 50 ° C., 25 parts of an acrylic copolymer having a methylmethacrylate / n-butylmethacrylate = 60/40 (weight) and an average molecular weight of 42000 was added and dissolved, followed by cooling to obtain the component (1). And benzoyl peroxide 50% as component (2)
Resin solution 1 was obtained by adding 4 parts of the plasticizer diluted product. When the viscosity of this resin liquid 1 at 20 ° C. was measured, it was 75 centipoise.

First, the resin liquid 1 is sufficiently applied to the surface of the concrete by using a brush, and the sheet-like material 1 made of the reinforced fiber to which the above-mentioned component (3) is adhered is further placed thereon, and then the resin liquid 1 is further placed thereon. 1 was applied to the entire surface of the sheet using a roller. The resin was cured by leaving it for 30 minutes at room temperature (23 ° C.). When a part of the sheet material of the reinforcing fiber cured according to JIS A6909 was peeled off from the concrete and an adhesion test was carried out, it was 780 kg / 1600.
A strength of mm ² was obtained, the concrete was peeled off together with the reinforcing fibers, sufficient curability and adhesiveness were obtained, and sufficient reinforcing strength was exhibited. The resin content of the repair and reinforcement layer was 58% by weight.

Example 2 41.7 parts of Epicoat 1004 (manufactured by Yuka Shell Epoxy Co., Ltd.) was added to 20 parts of methyl methacrylate containing a polymerization inhibitor, and the mixture was heated and dissolved at 80 ° C.
0.8 parts of triethylamine was added as a reaction catalyst, 3.5 parts of methacrylic acid was further added dropwise, and the mixture was reacted for 8 hours to obtain an epoxy methacrylate resin solution having an acid value of 5.
To this resin solution, 32 parts of methyl methacrylate, 1 part of γ-methacryloxypropyltrimethoxysilane, and 1 part of n-paraffin were added and dissolved, and then cooled to obtain component (1).
Then, 4 parts of benzoyl peroxide (50% plasticizer-diluted product) was added thereto as a component (2) to obtain a resin liquid 2. When the viscosity of this resin liquid 2 at 220 ° C. was measured, it was 220 centipoise. On the other hand, as the component (3), a liquid of N, N-diethyl-p-toluidine was spray applied to the same sheet material as used in Example 1 so as to have an average of 10 g / m ² to obtain the component (3). 2) was obtained.

First, the resin liquid 2 is sufficiently applied to the surface of the concrete by using a brush, and the sheet-like material 2 made of the reinforced fiber to which the above-mentioned component (3) is adhered is further placed thereon, and then the resin liquid is further applied thereon. 2 was applied to the entire surface of the sheet using a roller. The resin was cured by leaving it at room temperature at 20 ° C. for 30 minutes. Part of the reinforcing fiber cured in accordance with JIS A6909 was peeled off from the concrete, and an adhesion test was carried out. As a result, a strength of 670 kg / 1600 mm ² was obtained, and the concrete was peeled off together with the reinforcing fiber, and sufficient hardening and adhesion were achieved. Sex was obtained. In addition, sufficient reinforcing strength was developed. The resin content in the reinforcing layer was 52% by weight.

[0032]

According to the present invention, existing structures made of concrete such as piers, bridges, and columns of buildings can be repaired and reinforced in a short time without being affected by the surrounding temperature or environment.
Moreover, an excellent reinforcing effect can be exhibited.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takeo Konishi, Hideo Konishi 4-chome, Sunadabashi 1-chome, Higashi-ku, Nagoya, Aichi Prefecture, Mitsubishi Rayon Co., Ltd. No. 1-60 Mitsubishi Rayon Co., Ltd. Product Development Laboratory (72) Inventor Mikio Takasu 4-60 Sunadabashi, Higashi-ku, Aichi Prefecture Nagoya City Mitsubishi Rayon Co., Ltd. Product Development Laboratory

Claims (6)

[Claims] 1. A resin comprising the following components (1) and (2) as a resin when repairing and reinforcing an existing structure with a fiber-reinforced resin layer obtained by impregnating a sheet-shaped material made of reinforcing fibers with a resin and curing the resin. A method for repairing and reinforcing existing structures, characterized in that the resin is impregnated into a sheet-like material made of reinforced fibers to which the following component (3) is attached in advance to start curing. Component (1) At least one vinyl-polymerizable monomer and / or oligomer Component (2) Organic peroxide Component (3) Curing accelerator 2. The method for repairing and reinforcing existing structures according to claim 1, wherein the component (1) is at least one vinyl-polymerizable monomer and / or oligomer containing (meth) acrylate as a main component. 3. A resin comprising the components (1) and (2) is 2
The method for repairing and reinforcing existing structures according to claim 1 or 2, which is a resin having a viscosity of 5 to 10 ⁴ centipoise at 0 ° C. 4. A resin comprising components (1) and (2),
A resin containing paraffin wax.
Alternatively, the method for repairing and reinforcing the existing structure described in 3 above. 5. The sheet-shaped article made of reinforcing fibers is a sheet-shaped article obtained by heat-sealing a heat-fusible fiber cloth on at least one surface of a sheet-shaped article made of reinforcing fibers aligned in one direction. The method for repairing and reinforcing an existing structure according to claim 1, 2, 3 or 4. 6. A sheet of reinforcing fibers comprising a heat-fusible fiber in a direction orthogonal to the reinforcing fibers on at least one surface of the sheet of reinforcing fibers aligned in one direction. 5. A sheet-like material which is arranged at intervals of 3 to 150 mm along the longitudinal direction and heat-sealed.
Method for repairing and reinforcing existing structures described.