WO1999061725A1

WO1999061725A1 - Method for repairing and reinforcing existing concrete structure and resin

Info

Publication number: WO1999061725A1
Application number: PCT/JP1999/002756
Authority: WO
Inventors: Masahiro Sugimori; Tomoo Sano; Yasushi Suzumura; Takuya Furukawa; Mikio Takasu; Shigetsugu Hayashi
Original assignee: Mitsubishi Rayon Co., Ltd.
Priority date: 1998-05-26
Filing date: 1999-05-26
Publication date: 1999-12-02
Also published as: TW508401B; KR20010071320A; EP1083274A1; KR100429959B1; CA2333419A1; EP1083274A4

Abstract

A method of repairing and reinforcing an existing concrete structure, such as a bridge pier and a building, comprising: pasting on the surface of such a concrete structure a reinforcing fiber sheet material of a resin content of not more than 15 wt.% while impregnating the same sheet material with a resin having a viscosity of 2.5-300 poise and curing time of 1-24 hr.; and curing the resin; the method enabling an existing concrete structure to be repaired and reinforced to have a high strength in a short period of time with ease substantially without being influenced by a temperature condition during the repairing and reinforcing work.

Description

Specification

Repair and reinforcement method for existing concrete structures and resin

The present invention relates to a method for repairing and reinforcing an existing concrete structure such as a pier, a bridge, or a pillar of a building, and a resin used for the method.

This application is based on a patent application to Japan (Japanese Patent Application No. 10-144429), the contents of which are incorporated herein as a part of the present specification. Background art

As a method of repairing and reinforcing existing concrete structures such as bridge piers, a method is known in which a steel plate is attached with an anchor bolt or the like, an epoxy resin is injected into a gap between the steel plate and the concrete, and the resin is hardened and bonded. Recently, a method of impregnating epoxy resin or the like into a reinforced fiber sheet material and attaching it to the surface of an existing concrete structure has been spotlighted, and the results are gradually increasing. This method has the advantage that, compared to the method using steel plates, there is no need to transport, assemble, or weld heavy objects such as steel plates.

However, the epoxy resin mainly used for impregnating the reinforced fiber sheet material generally requires several days or more even at room temperature to cure and develop sufficient strength, and when the temperature is further lowered to 5 ° C or less. Unless a special heating means is used, there is a problem that the curing hardly progresses and the period of the curing becomes extremely long.

In order to solve the problems of such epoxy resins, a method of using a radical polymerizable resin that cures at a low curing temperature of 5 ° C and at a very low temperature of about 10 ° C as an impregnating resin is used. (Eg, Japanese Unexamined Patent Publication (A) Hei 9-184304, Hei 9-184405, Hei 10-775). However, the means of using such a radical polymerization type resin as the impregnating resin is to combine with a reinforcing fiber sheet material in a form suitable for a radical polymerization type resin system in the first place. When used in combination, an excellent reinforcing effect can be achieved, but a reinforcing fiber sheet material developed as an impregnating resin using an epoxy resin that is widely used today, for example, on a support sheet via an adhesive layer Reinforced fiber sheet material in which reinforcing fibers are aligned in one direction (Japanese Patent Laid-Open Publication (A) Hei 3-2224901, Hei 3-2 222 734, Hei 5-3 284) and a reinforced fiber sheet material in which reinforced fibers are impregnated with a small amount of resin having a resin content of 15% by weight or less (Japanese Patent Laid-Open Publication (A) Hei 7 — 346777, When combined with No. 7-2 287 14), there is a problem that the hardening near the reinforcing fiber does not proceed sufficiently due to the difference in the reaction method of the resin, and as a result the reinforcing effect is inferior. Have. Disclosure of the invention

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by using an additional impregnating resin having a specific range of viscosity and curing time, the resin content developed as an impregnating resin with epoxy resin is 1%. The present inventors have found that a sufficient reinforcing effect can be exhibited even when a reinforcing fiber sheet material of 5% by weight or less is used, and the present invention has been achieved.

That is, the present invention relates to a reinforcing fiber sheet material having a resin content of 15% by weight or less, while impregnating a resin having a viscosity of 2.5 to 300 voids and a curing time of 1 to 24 hours with an existing resin. The first point is to repair and reinforce existing concrete structures that are attached to the surface of concrete structures and hardened with resin.

Further, after affixing a reinforcing fiber sheet material having a resin content of 15% by weight or less to the surface of the existing concrete structure, the viscosity is 2.5 to 300 voise and the curing time is 1 to 24. The second point is the method of repairing and reinforcing existing concrete structures that impregnate the resin for a certain amount of time and cure the resin.

In the present invention, the resin to be impregnated later into the reinforced fiber sheet material (that is, a resin having a viscosity of 2.5 to 300 voids and a curing time of 1 to 24 hours) is additionally impregnated. It is called resin.

The additional impregnated resin has a viscosity of 100 to 100 voids and a curing time of 2 A radically polymerizable resin of up to 12 hours is particularly desirable, and this is the third aspect.

According to the present invention, even when a reinforcing fiber sheet material having a resin content of 15% by weight or less, which has been developed as an impregnating resin using an epoxy resin which is relatively widely used for repair and reinforcement of existing concrete structures, is used. Independent of temperature conditions, it can be cured in a relatively short time within one day, can be carried out extremely easily, can be applied even at low temperatures, and has an excellent reinforcing effect I do. BEST MODE FOR CARRYING OUT THE INVENTION

(Reinforced fiber sheet material-resin)

In the method for repairing and reinforcing an existing concrete structure according to the present invention, a reinforcing fiber sheet material composed of reinforcing fibers and a resin having a limit of 15% by weight is preferably used in a repairing and reinforcing method using an epoxy resin as an impregnating resin. Is used.

Here, the resin (matrix resin) constituting the reinforcing fiber sheet material is impregnated with the reinforcing fiber, or the reinforcing fiber aligned with the bow I or the woven reinforcing fiber is, for example, a release paper or a support. It may be an adhesive layer that adheres to the sheet. In the present invention, the resin constituting the reinforcing fiber sheet material may be an uncured thermosetting resin or a polymerized thermoplastic resin, and is not particularly limited. Resins are commonly used. Of course, there is no problem even if the reinforcing fiber sheet material is specially manufactured according to the resin to be impregnated later (additional impregnating resin). When the additional impregnating resin uses an acrylate ester or a methacrylate ester as the radical polymerizable monomer, the resin constituting the reinforcing fiber sheet material has a solubility parameter (SP) value of 17 to 2 as described later. It is preferable to use a resin having 8 (MPa) ^1/2 .

It is necessary that the amount of the matrix resin constituting the reinforcing fiber sheet material is 15% by weight or less. When the amount of the resin exceeds 15% by weight, it is not preferable because curing failure of the additional impregnated resin and deterioration of physical properties of the cured product are caused. Reinforced fiber When the amount of the resin constituting the sheet material is 7% by weight or less, when the type of the resin constituting the reinforcing fiber sheet material is different from the type of the resin to be impregnated later, for example, the reinforcing fiber The resin constituting the sheet material is an epoxy resin, which is particularly preferable even when the reinforced fiber sheet material is later impregnated with a radical polymerizable resin, since sufficient curability and strength of the cured product can be obtained. Since the amount of resin constituting the reinforced fiber sheet material greatly affects the handleability of the reinforced fiber sheet material, the amount of the resin is preferably 1% by weight or more. In addition, the reinforced fiber sheet material has a sufficiently low rigidity so that the resin that composes it can be attached to the existing concrete structure with a curvature, so that the resin constituting the material is uncured or along the attached place with the curvature. Alternatively, it is preferable that the resin be cured in a suitable form. Of course, when using an uncured resin, it is preferable that the pot life (shelf life) at room temperature is long.

(Reinforcing fiber sheet material-Reinforcing fiber)

As the reinforcing fibers constituting the reinforcing fiber sheet material in the present invention, fibers usually used as reinforcing fibers such as carbon fiber, aramide fiber and glass fiber are preferably mentioned. Among them, carbon fiber is preferable.

As the reinforcing fiber, a high-strength carbon fiber having a tensile strength of 400 OMPa or more is particularly preferable when utilizing the strength, and a high elasticity having an elastic modulus of 250 GPa or more when using the elastic modulus. Carbon fibers are more preferred.

When carbon fiber is used as the reinforcing fiber of the reinforcing fiber sheet material and a radical polymerizable resin is used as the resin to be impregnated later, a compound having a radical polymerizable functional group at at least one end is used as a sizing agent. It is particularly preferable to use the carbon fiber used as the material in view of the strength development of the cured product.

(Reinforced fiber sheet material-reinforced form)

In the present invention, the reinforcing form in the reinforcing fiber sheet material is not limited at all, and examples include a method in which reinforcing fibers are aligned in one direction or formed into a woven sheet. From the viewpoint of the effect of repair and reinforcement, the basis weight of the reinforcing fiber is preferably 150 g Zm ² or more. Examples of the form more preferably used as the reinforcing fiber sheet material used in the present invention include Japanese Patent Application Laid-Open Publications (A) Hei 3-2224901, Hei 3-222 734, Hei 5 As described in No. 3 804, No. 7-364 777, and No. 7-2 287 14, the following forms (1) to (3) are preferable . (1) A reinforced fiber sheet material in which a reinforcing fiber woven fabric is formed by lining up or weaving in one direction to form a reinforced fiber woven fabric, having a reinforcing fiber weight of 150 g / m ² or more, and impregnating a resin within the above range. (2) A reinforced fiber sheet material obtained by laminating a glass fiber cloth on at least one surface of the reinforced fiber sheet material according to (1). (3) A reinforced fiber sheet material in which reinforcing fibers are unidirectionally arranged on a support sheet via an adhesive layer.

Here, as the support sheet, a nonwoven fabric of fibers of various polymers such as glass fiber woven fabric, glass scrim cloth, glass fiber paper, glass fiber nonwoven fabric, polyamide, and polyphenylene sulfide is used.

The adhesive may be any as long as it can at least temporarily adhere the reinforcing fibers to the support, and is preferably a resin having good compatibility with the matrix resin of the reinforcing fiber sheet material. For example, if the matrix resin is an epoxy resin, an epoxy adhesive is preferred.

Of course, the reinforcing fiber sheet material used in the present invention is not limited to the above-described reinforcing fiber sheet material. For example, after reinforcing fibers are aligned in one direction, or after manufacturing, the reinforcing fiber sheet is used. A resin in which the resin constituting the material is applied in a linear or dot shape to maintain the form, and a resin in which the above-mentioned support sheet is further bonded thereto can be applied.

(Additional impregnation resin)

In the present invention, the reinforcing fiber sheet material is impregnated with a curable resin at the same time as or after attaching the reinforcing fiber sheet material to the surface of the existing structure. In the present invention, the additional impregnated resin may be a resin having a viscosity of 2.5 to 300 vois and a curing time of 1 to 24 hours, which may be repaired and reinforced using the above-mentioned reinforcing fiber sheet material. It is necessary to enhance the effect.

The viscosity of the resin to be impregnated here is the viscosity measured at the construction temperature using a B-type viscometer. When the resin to be impregnated is a radical polymerization type resin, the viscosity is before addition of an organic peroxide or the like serving as a polymerization initiator. When the viscosity of this resin exceeds 300 voids, it becomes difficult to impregnate the reinforcing fiber sheet material with the resin.On the contrary, when the viscosity is less than 2.5 voids, the combination with the above-mentioned reinforcing fiber sheet material becomes difficult. During the resin impregnation and curing steps, the reinforcing fibers tend to move, causing a reduction in the reinforcing effect. More preferably, the lower limit of the viscosity is 100 voids and the upper limit is 100 voids.

Further, the curing time in the present invention is a time from the start of curing of the resin to a time when the tackiness is eliminated by touch with a finger, and when a resin having a curing time of less than 1 hour is used, the development of strength is poor. Conversely, a resin having a curing time exceeding 24 hours is too long for the purpose of the present invention because the curing time is too long.

The lower limit of the curing time is more preferably 2 hours or more, and the upper limit is more preferably within 12 hours, most preferably within 8 hours.

As the kind of the resin, a resin that satisfies the requirements of the viscosity and the curing time described above is preferable, and among them, a thermosetting resin is preferable, and a room temperature curable resin is particularly preferable. From the viewpoint of low-temperature curability, a radical polymerizable resin is particularly preferable, and a radical polymerizable resin composed of a radical polymerizable monomer or oligomer having a methacryl group or an acryloyl group as a terminal reactive group is cured. It is particularly preferable from the viewpoint of the balance between the properties and the properties of the cured product.

As long as the composition satisfies the requirements of the viscosity and the curing time, the terminal reactive group may be a composition containing a monomer other than a methyl group or an acryloyl group, for example, styrene.

Radical polymerizable monomers include acrylates such as methyl acrylate and ethyl acrylate, methyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl methacrylate, and tetrahydrofurfuryl methacrylate. Examples thereof include methacrylate, styrene, vinyltoluene, divinylpentene, and acrylonitrile, which can be used alone or in combination according to the purpose. Among them, acrylates and methacrylates are particularly preferred in terms of curability and strength. In addition, since the radical polymerizable monomer in the present invention is preferably a monomer that is compatible with the resin adhering to the reinforcing fiber sheet to some extent, the solubility parameter of the radical polymerizable monomer has an SP value of 17 to 2 Those having a range of 2 (MP a) ² are particularly preferred.

The SP value of a radically polymerizable monomer can be calculated from SP = ∑ (Wn / 100 SPn) [Wn: weight fraction of n monomers, SPn: SP value of n monomers] Examples of polymerizable oligomers include acrylic acid, methacrylic acid, etc. at the ends of oligomers obtained by the reaction of polybasic acids such as fluoric acid and adipic acid with polyhydric alcohols such as ethylene dalicol and butanediol. Poly (meth) acrylate containing acryloyl group and methacryl group introduced by the reaction with alcohol, alcohol containing allylic ether group such as polybasic acid and polyhydric alcohol, pentaerythritol triallyl ether, and trimethylolpropanediaryl ether And (meth) acrylic acid-containing polyester poly (meth) acrylates obtained by reaction with acrylic acid, polybasic acids and polyhydric alcohols An aryl group-containing polyester obtained by a reaction with an aryl ether group-containing alcohol, an epoxy poly (meth) acrylate obtained by a reaction of an epoxy resin with (meth) acrylic acid, a polyol and a polyisocyanate, and a hydroxyl group-containing (meth) Examples thereof include, but are not limited to, urethane poly (meth) acrylate obtained by a reaction with acrylate.

The molecular weight of the radically polymerizable oligomer used in the present invention is not particularly limited, but it is more preferably 1000 or less in terms of number average molecular weight from the viewpoint of curability at low temperatures.

In order to impart toughness and durability to the cured product, it is of course possible to add an elastomer component having a reactive functional group at the terminal as a reactive oligomer. The mixing ratio of the monomer and the oligomer in the resin for impregnation used in the present invention is not particularly limited as long as the viscosity and curing time of the composition are satisfied. As initiators for initiating the polymerization of these radically polymerizable monomers and oligomers, commonly used curing agent systems, for example, peroxides and metal accelerators and curing accelerators such as tertiary amines are used. Examples thereof include redox catalysts and the like. The combination is selected and used such that the curing time is 1 hour or more, 24 hours or less, preferably 12 hours or less.

The polymer added instead of or in addition to the oligomer of the resin for impregnation is added for the purpose of adjusting the viscosity of the composition and improving the toughness and durability of the cured product. Preferred polymers include elastomeric polymers such as acrylic polymers, acrylonitrile rubber rubbers, acrylic rubbers, styrene block polymers, and urethane elastomers. However, it is not limited to this. The amount of the polymer to be added is not particularly limited as long as it satisfies the restrictions on the viscosity and curing time of the composition, but is preferably 50% by weight or less in many cases.

It is preferable that the radical polymerizable monomer and the non-reactive polymer be the main components, since the resin viscosity can be appropriately controlled.

Further, when a radical polymerizable monomer and a radical polymerizable oligomer having a number average molecular weight of 1,000 or less and a non-reactive polymer are the main components, the reactivity of the resin and the resin viscosity can be appropriately controlled. preferable.

The radically polymerizable resin in the present invention includes, in addition to the above-mentioned monomers, oligomers, polymers, and curing agent components, a thixotropic agent, an air-curing agent, a coupling agent, a polymerization inhibitor, and a coloring agent according to the purpose. Examples of the thixotropy-imparting agent that can be contained therein include finely divided silica such as "Varodil 200" manufactured by Nippon Aerosil Co., Ltd. and "Nibusir LP" manufactured by Nippon Silica Industry Co., Ltd .; Organic powders such as finely divided calcium carbonate such as "Shirarenka CC" manufactured by Maruo Calcium Co., Ltd. and "Nanox 25" manufactured by Maruo Calcium Co., Ltd. or "Disparon 3005" manufactured by Kusumoto Kasei Co., Ltd. It is not limited to. The amount used is less than 10% by weight, usually less than 5% by weight. Examples of the air curing agent include paraffin wax represented by n-paraffin, higher fatty acids such as polyethylene wax and stearic acid, and glycidyl methacrylate, aryl glycidyl ether and the like. Monoepoxy compounds, acrylic acid derivatives of dicyclopentene, and commercially available compounds having an air drying function, such as "Ripoxy AC-201" manufactured by Showa Polymer Co., Ltd., can be used alone or in combination. The addition amount of these air-curing agents is suitably from 0.1 to 10% by weight based on the resin to be impregnated, and if it is less than 0.1% by weight, sufficient air-curing properties cannot be obtained. If the content exceeds 10% by weight, the physical properties of the cured product tend to decrease. When a higher fatty acid such as paraffin wax is used, the range is particularly preferably 0.1 to 5% by weight based on the resin to be impregnated.

The resin used in the present invention may be, if necessary, a silane coupling agent typified by acryloxypropyltrimethoxysilane, a titanate coupling agent, a zirconate coupling agent, an organic aluminum coupling. A power coupling agent such as an agent can be used alone or as a mixture. An appropriate amount of addition is 0.5 to 5 parts by weight based on 100 parts by weight of the resin to be impregnated.

It is preferable that the resin used in the present invention contains an appropriate amount of a polymerization inhibitor in order to secure stability at the distribution stage. Further, a coloring agent, a pigment, an antifoaming agent, and the like can be added as needed.

In the present invention, the amount of the additional impregnating resin impregnated into the reinforcing fiber sheet material is not particularly limited as long as the reinforcing fiber sheet and the additional impregnating resin become an integrated composite material after impregnation.

(Procedure for repair and reinforcement)

The procedure for repairing and reinforcing existing concrete structures according to the present invention will be described.

In the present invention, the reinforced fiber sheet material is impregnated with a resin and is attached to the surface of an existing concrete structure to cure the resin, or the reinforced fiber sheet material is coated on the surface of the existing concrete structure. Can be carried out by impregnating with a resin and curing the resin. At this time, before attaching the reinforcing fiber sheet material The resin to be impregnated later may be preliminarily applied to the sticking place.

The surface of the existing concrete structure to which the reinforcing fiber sheet material is to be attached must be smoothed using a grinder or the like to remove irregularities, steps, defects, cracks, etc. It is preferable to correct by filling in from the viewpoint of improving the bonding strength.

On the surface of the existing concrete structure to which the reinforcing fiber sheet material is to be attached, apply the appropriate amount of primer resin to the surface of the concrete by known means, such as brushing with a roller or spraying, if necessary, after removing the above irregularities. It is preferable to use a resin of the same type as the impregnating resin used later for attaching the reinforcing fiber sheet material. It is preferable that the primer resin has a low viscosity from the viewpoint of adhesiveness to concrete and workability, and the primer resin is a composition that hardens more quickly, for example, a composition that cures in about one hour. Such a primer resin is used by mixing a curing agent and a curing accelerator immediately before use.

Examples of the acrylic primer resin that can be used in the present invention include, but are not limited to, “Acrycillap DR-80” manufactured by Mitsubishi Rayon Co., Ltd.

In the method of the present invention, the resin to be impregnated is used by mixing a curing agent and a curing accelerator immediately before use so that a predetermined curing time can be obtained.

As a more preferable repair / reinforcement method of the present invention, the additional impregnated resin is applied to the surface of an existing concrete structure to which the primer resin has been applied, and the reinforced fiber sheet material is adhered thereon, and then The additional impregnated resin is applied to the reinforcing fiber sheet material while extruding the air contained in the sheet by, for example, applying a defoaming hole to the air through a defoaming port. According to the purpose, the required number of reinforcing fiber sheet materials can be attached while changing the fiber direction, thereby forming a repair reinforcing layer using a reinforcing fiber sheet.

Finally, it is of course possible to apply painting or mortar coating as required Example

Hereinafter, the present invention will be described more specifically with reference to examples.

(Example 1)

(Synthesis of oligomer 1)

In a vessel equipped with a stirrer, temperature controller, and condenser, 148 parts by weight of hydrofluoric anhydride, 1227 parts by weight of methyl methacrylate, 230 parts by weight of pen erythritol triaryl ether ("P-30M" manufactured by Daiso Corporation), 3.8 parts by weight of dimethylaminoethyl methacrylate and 0.38 parts by weight of hydroquinone monomethyl ether were added and reacted at a reaction temperature of 85 ° C. for 3 hours to obtain a resin solution containing an aryl group-containing carboxylic acid. Furthermore, bisphenol A type epoxy resin ("Epico 1004" manufactured by Yuka Shell Epoxy Co., Ltd.) 1943 parts by weight, 86 parts by weight of methacrylic acid, 40 parts by weight of dimethylaminoethyl methacrylate, 2 parts by weight of hydroquinone monomethyl ether And 1227 parts by weight of methyl methacrylate, and the reaction temperature was raised to 9 O. The reaction was continued until the acid value became 8 (mgKOH / g) or less, to obtain an oligomer 1 containing 50% by weight of methyl methacrylate. Was. The number-average molecular weight of the composition obtained by removing the monomer component of the obtained oligomer 1 was 2,000.

(Preparation of impregnated resin)

100 parts by weight of a mixture of methyl methacrylate (SP value: 18) and oligomer 1 (weight ratio of 10 at 25 ° C), 100 parts by weight of n-paraffin as an air-curing component 1 part by weight Also, 1 part by weight of methacryloxypropyltrimethoxysilane as a silane coupling agent, 1 part by weight of cumene hydroperoxide as an initiator, and 1 part by weight of cobalt naphthenate as a curing accelerator were added.

(Production of reinforced fiber sheet material)

Epoxy ester ("3002M" manufactured by Kyoei Yushi Kagaku Kogyo Co., Ltd.) whose main component is bisphenol A derivative with methacrylic group at the end 1 wt% the deposited carbon fiber (manufactured by Mitsubishi Rayon Co., Ltd. "TR50") (tensile strength of 490 OMP a) a aligned in one direction so that the weight of the carbon fibers per 1 m ² is 300 g, the curing agent 15 g per lm ^{2 of an} epoxy resin composition containing no resin ("Base resin for # 350" manufactured by Mitsubishi Rayon Co., Ltd., SP value: 23), and then impregnated with a thickness of 25 ^ m as a support. Was bonded to obtain a reinforced fiber sheet material 1.

(Resin impregnation and curing)

The reinforcing fiber sheet material 1 was impregnated with the above impregnated resin so that the amount of resin per lm ² was approximately 400 g, and was left to cure at 25 ° C. After 2 hours, the resin disappeared from the surface and hardened.

A sample for a tensile test was prepared from the cured reinforcing fiber sheet material, and the tensile strength in the carbon fiber direction was measured. The average tensile strength of this composite was 410 OMPa in terms of 100% of carbon fiber.

In addition, an acrylic primer resin ("Acrylic Wrap DR-80" manufactured by Mitsubishi Rayon Co., Ltd.) was applied to the surface of a concrete sample conforming to JIS (Japanese Industrial Standards) A-1132 at 25 ° C with a brush. after coating at a rate of lm ² per 200 g, it was adhered reinforcing fiber sheet material 1 in the same manner as described above in concrete surfaces. After curing for one day, a tensile test was performed in accordance with JIS-A-6909. The strength was 2.4 MPa and the failure mode was material failure inside the concrete.

(Example 2)

The above-mentioned oligomer 1 and an epoxy-based oligomer ("Epoxyester 3000M" manufactured by Kyoeisha Chemical Co., Ltd .; hereinafter, referred to as oligomer 2) were used in combination as the oligomer, and the ratio was changed as shown in Table 1 except that the ratio of each component was changed as shown in Table 1. The procedure was the same as in Example 1. Table 1 shows the evaluation results.

(Example 3)

The operation was performed in the same manner as in Example 2 except that the amount of the curing accelerator used was halved. Table 1 shows the evaluation results. (Example 4)

(Synthesis of oligomer 3)

In a container equipped with a stirrer, temperature controller and condenser, bisphenol A type epoxy resin ("Epicoat 1004" manufactured by Yuka Shell Epoxy Co., Ltd.) 58 3 parts by weight, acrylic acid 43 parts by weight, dimethylaminoethyl methyl Add 6.2 parts by weight of acrylate, 0.62 parts by weight of hydroquinone monomethyl ether, and 633 parts by weight of methyl methacrylate, raise the reaction temperature to 90 ° C, and reduce the acid value to 5 (mg KOH / g) or less. The reaction was continued until the reaction was completed to obtain an oligomer 3 containing 50% by weight of methyl methacrylate. The number average molecular weight of the composition obtained by removing the monomer component of the obtained oligomer 3 was 2,300.

(Preparation of impregnated resin)

The same operation as in Example 1 was carried out except that oligomer 3 was used instead of oligomer 1 as an oligomer component and the ratio of each component was changed as shown in Table 1. Table 1 shows the evaluation results.

(Example 5)

Example 1 was repeated except that an acrylic resin ("Dianal BR-83" manufactured by Mitsubishi Renyon Co., Ltd.) was used instead of Oligomer 1 and the ratio of each component was changed as shown in Table 1. The same operation was performed. Table 1 shows the evaluation results.

(Example 6)

The same operation as in Example 5 was carried out except that the amount of the curing accelerator used was halved. Table 1 shows the evaluation results.

(Comparative Example 1)

The monomer component and the oligomer component were mixed at the ratios shown in Table 1 to prepare a resin composition having a viscosity of 2 voids at 25 ° C. before mixing the initiator, and the same operation as in Example 1 was performed. It is shown in Table 1. The curability of the impregnated resin was extremely good, and the adhesion to the concrete was good, but the tensile strength of the composite was insufficient at 3720 MPa.

(Examples 7, 8) Using the same impregnating resin as in Comparative Example 1, the test was performed by changing the sample preparation temperature to 5 ° C. and −10 ° C., respectively.

At this time, the amount of the curing accelerator was changed as shown in Table 1 so that the curing time was 5 hours. The viscosity of the composition at 5 ° C. was 15 boise, and the viscosity at —10: was 45 boise.

The results are shown in Table 1. As the temperature for preparing test specimens was lowered, the viscosity of the resin increased, and sufficient tensile strength was developed.

(Comparative Example 2)

The curing agent of the resin composition used in Comparative Example 1 was changed so that the curing time was 30 minutes. The evaluation results are shown in Table 1, but the tensile strength of the composite was further reduced.

(Comparative Example 3)

The monomer component and the polymer component were mixed in the ratio shown in Table 1 to prepare a resin composition having a viscosity of 400 vise at 25 ° C, and the same test was carried out. The subsequent evaluation could not be carried out due to the difficulty of impregnating the resin with the resin.

table 1

The abbreviations in Table 1 above indicate the following substances, respectively.

MM A: Methyl methacrylate

2-EHA 2-ethylhexyl acrylate

P EGA phenoxyethylene dalicol acrylate CHPO cumene B PO: Benzoyl peroxide

NC: Cobalt naphthenate

DMPT: N, N-dimethyl-p-toluidine

n-P: n—paraffin

rMX: methacryloxypropyl trimethoxysilane

01: Oligomer 1

02: Oligomer 2 Epoxy oligomer ("Epoxy ester 3000 株式会社" manufactured by Kyoeisha Chemical Co., Ltd.)

03: Oligomer 3

Ρ1: Acrylic resin ("Dianal BR-83" manufactured by Mitsubishi Rayon Co., Ltd.)

(Comparative Example 4)

Bisphenol Α type epoxy resin ("Epicoat 828" manufactured by Yuka Shell Epoxy Co., Ltd.) 60 parts by weight, trimethylolpropane triglycidyl ether

(Adeka Glycrolle ED-505 "manufactured by Asahi Denka Kogyo Co., Ltd.) 40 parts by weight of an aliphatic polyamine-based curing agent (AC IJ apan, Inc." Ancamine 2021 ") 45 parts by weight mixed with a room temperature curable epoxy resin composition Was prepared. The viscosity of the composition was 50 boise at 25 ° C.

The epoxy resin composition was impregnated into the reinforcing fiber sheet used in Example 1 to prepare a composite tensile test piece. When the resin was left for 12 hours, it did not stick, but required 7 days to develop sufficient strength and elasticity. The tensile strength evaluated after 7 days was 420 OMPa.

The same test was performed at 5 ° C, but the resin did not cure and was abandoned. (Example 9)

As the impregnating resin, vinyl ester resin (“Lipoxy R — 840” manufactured by Showa Polymer Co., Ltd., viscosity at 25 ° C. 25 Boys, SP value: 19) 100 parts by weight, curing catalyst (CH Showa Polymer Co., Ltd.) 1), Naphthene as a curing accelerator The same operation as in Example 1 was carried out except that 0.3 part by weight of cobalt acid was used. Curing time at 25 ° C was 3 hours. Six hours after the resin was impregnated with the reinforcing fiber sheet material, the surface tack had completely disappeared, and the tensile strength of the composite was 402 OMPa.

(Example 10)

The same operation as in Example 9 was carried out except that 2 parts by weight of methyl ethyl peroxide as a curing agent and 1 part by weight of cobalt naphthenate as a curing accelerator were used per 100 parts by weight of the resin. The curing time at 25 ° C. was 1 hour, and the tensile strength of the obtained composite after 6 hours was 300 OMPa.

(Example 11)

The test was performed in the same manner as in Example 7 except that an n-butyl acrylate oligomer having a methacryl group at one end and a number average molecular weight of 6000 was used instead of phenoxyethylene glycol acrylate. . The viscosity of the resin at 5 ° C. was 5 boys.

The surface of the prepared sample had no tackiness after 6 hours, and the composition had good low-temperature curability. The tensile strength of the composite was 4100 MPa, and the failure mode in the adhesion test was material failure of concrete.

(Example 12)

As in Example 1, reinforced fiber was used in the same manner as in Example 1 except that "Conwood Net ON 5050" (basis weight Y gZm ² ) manufactured by Nisseki Palette System Co., Ltd. was used instead of "Scrim Cloth" manufactured by Nitto Boseki Co., Ltd. Sheet 2 was created. The same operation as in Example 3 was performed by combining this reinforcing fiber sheet material with the resin used in Example 3. The tensile strength of the obtained composite was 4,300 MPa, a value indicating sufficient strength development.

(Example 13)

As the carbon fiber, a high elasticity carbon fiber having an elastic modulus of 392 GPa ("HR40" manufactured by Mitsubishi Rayon Co., Ltd., tensile strength 4610MPa) is used. Except for using the resin composition used in Example 3, the same as in Example 1

The tensile strength of the bird was evaluated. The obtained tensile strength was 4.50 MPa, a value indicating sufficient strength development.

(Example 14)

As a reinforcing fiber sheet material, Tonen Co., Ltd.'s "Forcasheet FTS-C1-30" (a type of resin used) in which reinforcing fibers are aligned in one direction on a support sheet via an adhesive layer The tensile strength of the composite was evaluated in the same manner as in Example 1 except that the SP value: 23) was used and the resin composition used in Example 3 was used as the impregnated resin. The obtained tensile strength was 430 OMPa, a value indicating sufficient strength development. Industrial applicability

According to the present invention, repair and reinforcement of existing concrete structures, for example, piers and buildings, etc., can be performed with high strength in a short period of time without being substantially affected by temperature conditions or the like during the construction. In particular, existing reinforcing fiber sheet materials can be effectively used.

Claims

The scope of the claims

1. A reinforced fiber sheet material having a resin content of 15% by weight or less is impregnated with a resin having a viscosity of 2.5 to 300 voids and a curing time of 1 to 24 hours. Is a method of repairing and reinforcing existing concrete structures where resin is hardened by sticking it to the surface of existing concrete structures.

2. After affixing the reinforcing fiber sheet material with resin content of 15% by weight or less to the surface of the existing concrete structure, the viscosity is 2.5-300 voise and the curing time is 1- A method for repairing and reinforcing an existing concrete structure in which the reinforcing fiber sheet material is impregnated with the resin for 24 hours to cure the resin.

3. The method for repairing and reinforcing an existing concrete structure according to claim 1, wherein the reinforcing fiber weight of the reinforcing fiber sheet material is 150 g Zm ² or more.

4. The method for repairing and reinforcing an existing concrete structure according to claim 1, wherein the reinforcing fiber sheet material is a reinforcing fiber sheet material in which a resin is impregnated into aligned reinforcing fibers or a reinforcing fiber woven fabric.

5. The reinforced fiber sheet material is a reinforced fiber sheet material obtained by impregnating a reinforced fiber or a reinforced fiber woven fabric with a resin, and bonding a glass fiber cloth to at least one surface. Or the repair method for existing concrete structures described in 2.

6. The method for repairing and reinforcing an existing concrete structure according to claim 1 or 2, wherein the reinforcing fiber sheet material is a reinforcing fiber sheet material in which reinforcing fibers are aligned in one direction on a support sheet via an adhesive layer. .

7. The method for repairing and reinforcing an existing concrete structure according to claim 1, wherein the resin content of the reinforcing fiber sheet material is 7% by weight or less.

8. The method for repairing and reinforcing an existing concrete structure according to claim 1, wherein the reinforcing fibers constituting the reinforcing fiber sheet material are high-strength carbon fibers having a tensile strength of 400 MPa or more.

9. Reinforcing fibers constituting the reinforcing fiber sheet material have an elastic modulus of 250 GPa or less. 3. The method for repairing and reinforcing an existing concrete structure according to claim 1 or 2, wherein the high elastic carbon fiber is used.

10. The repair of an existing concrete structure according to claim 1 or 2, wherein the carbon fiber constituting the reinforcing fiber sheet material is a carbon fiber to which a compound in which at least one terminal group is a radical polymerizable functional group is attached. Reinforcement method.

1 1. The solubility parameter (SP) value of the resin constituting the reinforced fiber sheet material is 1

3. The method for repairing and reinforcing an existing concrete structure according to claim 1, wherein the pressure is 7 to 28 (MPa) ^1/2 .

12. Radical polymerizable resin with a viscosity of 10-100 boise and a curing time of 2-12 hours.

13. A radically polymerizable resin containing a component having a methacryl group or an acryloyl group at a terminal, having a viscosity of 10 to 100 boise and a curing time of 1 to 8 hours.

14. The resin according to claim 12, wherein a radical polymerizable monomer and a radical polymerizable oligomer having a number average molecular weight of 10,000 or less are the main components.

14. The resin according to claim 12, comprising a radical polymerizable monomer and a non-reactive polymer as main components.

16. The resin according to claim 12, comprising a radical polymerizable monomer, a radical polymerizable oligomer having a number average molecular weight of 10,000 or less, and a non-reactive polymer as main components.

17. The resin according to claim 12, wherein the radical polymerizable monomer component has a solubility parameter overnight (SP) value of 17 to 22 (MPa) ^1/2 .

18. Claim 12 or 1 containing 0.1 to 5% by weight of an air-curing component.

The resin described in 3.

19. In the method for repairing and reinforcing an existing concrete structure according to claim 1, the additional impregnating resin for impregnating the reinforcing fiber sheet material while attaching the material to the surface of the concrete structure is the resin according to claim 12 or 13. .

20. The method for repairing and reinforcing an existing concrete structure according to claim 2, The resin according to claim 12 or 13, wherein the additional impregnating resin for impregnating the reinforcing fiber sheet material stuck on the surface of the concrete structure.