JP2005163385A - Repair method for concrete structures - Google Patents

Abstract

A method of repairing a ceiling or side defect of a concrete structure in which the reinforcement sheet is not peeled off the surface of the concrete structure due to high adhesion between the surface of the concrete structure and the reinforcement sheet. provide.
When repairing a defect in a ceiling or side surface of a concrete structure, the defect is smoothed using an undercoat conditioner, and has a viscosity of 10,000 to 250,000 mPa · s and a TI value of 4 A concrete characterized in that the adhesive resin composition of ~ 9 is applied to the smoothed surface, and then a reinforcing material sheet having no fiber layer on the surface is applied to the applied surface of the adhesive resin composition. How to repair structures.
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Description

  The present invention relates to a method for repairing a concrete structure, and in particular, to a method for repairing a bridge portion and a bridge pier portion of a highway, a railroad or the like, or a missing portion on a ceiling portion or a side surface of a concrete structure such as a tunnel.

On the ceiling or side of a concrete structure that has passed through the years, there are defects such as concrete cracks, peeling and dropping due to concrete call joints, neutralization, alkali-aggregate reaction, salt damage, and the like. For the purpose of repairing such a defect part, when repairing a defect part on the ceiling or side of a concrete structure, the defect part is subjected to a smoothing process using a base preparation agent, and an adhesive is applied to the smoothing process. Next, the laminate fiber substrate made of a nonwoven fabric or other fiber substrate and a synthetic resin is applied to the adhesive, and at this time, the laminate is subjected to pressure treatment with a heating roller from the synthetic resin side. A repair method is known in which a fiber base material is impregnated with an applied adhesive.
Japanese Patent Laid-Open No. 2002-256707

  However, since the adhesive is impregnated into the fiber base material in the pasting of the laminate, there is a problem that an adhesive is not present at the interface between the smoothed surface and the fiber base material. There is a drawback that the body easily peels from the surface of the concrete structure.

  The present invention has been made in view of the above circumstances, and its purpose is that the adhesion of the surface of the concrete structure and the reinforcing material sheet is high, so that the reinforcing material sheet can be peeled from the surface of the concrete structure. It is an object of the present invention to provide a method for repairing a defect in a ceiling or a side surface of a concrete structure having no concrete.

  As a result of various studies, the present inventor has obtained the following knowledge. That is, if a reinforcing material sheet having no fiber layer on the surface is used instead of the above-described laminate, surprisingly, no adhesive is present at the interface between the smoothing surface of the concrete structure and the reinforcing material sheet. Since there is no existence part, it can adhere firmly.

  The present invention has been completed on the basis of the above knowledge, and the gist of the present invention is that when repairing a defect in a ceiling or a side surface of a concrete structure, a smoothing process is performed on the defect by using a base conditioner. The adhesive resin composition having a viscosity of 10,000 to 250,000 mPa · s and a TI value of 4 to 9 is applied to the smoothed surface, and then the reinforcing material sheet having no fiber layer on the surface is bonded. It exists in the repair method of the concrete structure characterized by sticking on the application surface of an agent resin composition.

  According to the present invention, the smoothing surface of the concrete structure and the reinforcing material sheet can be firmly bonded, and as a result, the concrete can be prevented from peeling off from the surface of the concrete structure. The industrial value of the invention is extremely large.

  Hereinafter, the present invention will be described in detail. The repair method of the present invention is basically the same as a conventionally known method, a step of performing a smoothing treatment using a base preparation agent, and a step of attaching a reinforcing material sheet using an adhesive resin composition including. In the present invention, before the step of smoothing, a step of adjusting the surface of the concrete structure with a conventionally known impregnating material, reinforcing steel rust preventive material, recess repair material, cracking injection material, etc. and a primer are applied. You may perform the process to do. In the present invention, a specific sheet having no fiber layer on the surface is used as the reinforcing material sheet, and an adhesive resin composition having a specific viscosity and TI value is used as the adhesive.

  An impregnation primer, putty, or the like can be used as the substrate conditioner used in the present invention. Among them, an epoxy resin primer that can impregnate concrete microcracks (width: 0.2 mm or less) and is excellent in wet adhesion is preferable.

  The adhesive resin composition used in the present invention includes an adhesive resin, a curing agent, and a diluent. Furthermore, in order to apply | coat an adhesive agent uniformly, it is preferable to contain the inorganic powder which has a specific particle diameter. Moreover, auxiliary agents, such as a conventionally used filler, additive, anti-sagging agent, and coloring agent, can be included as needed.

  The viscosity of the adhesive resin composition is 10,000 to 250,000 mPa · s (25 ° C. BH type rotational viscometer, 20 rpm), preferably 50,000 to 200,000 mPa · s (25 ° C. BH type rotational viscometer, 20 rpm). When the viscosity is less than 10,000 mPa · s, the adhesive resin composition hangs down on the wall surface of the concrete structure and the reinforcing material sheet is easily slipped off. Moreover, when a viscosity exceeds 250,000 mPa * s, application | coating becomes difficult and workability | operativity worsens.

  The TI (thixotropic index) value of the adhesive resin composition is 4 to 9 (25 ° C. BH type rotational viscometer, 2 rpm / 20 rpm), preferably 5 to 8 (25 ° C. BH type rotational viscometer, 2 rpm / 20 rpm). It is. When the TI value is less than 4, the reinforcing material sheet is easily slipped off. Moreover, when TI value exceeds 9, it becomes difficult to press-fit the reinforcing material sheet to the adhesive resin in the field construction.

  Examples of the adhesive resin used in the present invention include urethane resins, silicone adhesives, rubber adhesives, vinyl ester resins, polyester adhesives, polymer cement adhesives, acrylic adhesives, and polyolefin adhesives. Examples thereof include an adhesive and an epoxy adhesive.

  The curing agent is not particularly limited as long as it can cure the adhesive resin, and a known one is used. The diluent is not particularly limited as long as it dissolves the adhesive resin, and a known one is used.

  Of the above-described adhesive resins, an epoxy resin is preferable in consideration of adhesiveness, chemical resistance, shrinkage resistance, and handleability. Specific examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, hydrogenated epoxy resin of the above resin, novolac type epoxy resin, glycidyl ester type epoxy resin, urethane modified epoxy resin , Nitrogen-containing epoxy resins, epoxy resins derived from alcohols, polybutadiene, natural rubber, rubber-modified epoxy resins derived from natural rubber having terminal carboxyl groups, flame retardant epoxy resins containing bromine, alicyclic epoxies Resin etc. are mentioned.

  Considering high curing reactivity or easy formation of a three-dimensional network structure in the cured product, an epoxy resin containing at least two epoxy groups in the molecule is preferable. Specifically, novolak-type epoxy resins such as epichlorohydrin-bisphenol A type epoxy resin and epichlorohydrin-bisphenol F type epoxy resin are more preferable.

  The epoxy resins can be used alone or as a mixture. Moreover, it can be used as a mixture with the monoepoxy compound which reduces the viscosity of an epoxy resin.

  Examples of epoxy resin curing agents include triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-aminoethylpiperazine, m-xylylenediamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, isophoronediamine, 2, Amines such as 4,6-tris (dimethylaminomethyl) phenol, tertiary amine salts, polyamide resins, imidazoles, dicyandiamides, ketimines, boron trifluoride complex compounds, phthalic anhydride, hexahydrophthalic anhydride , Tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, dodecinyl succinic anhydride, pyromellitic anhydride, chlorenic anhydride and other carboxylic anhydrides, alcohols, phenols, carboxylic acids, etc. And the like.

  Examples of the diluent for the epoxy resin include butyl glycidyl ether, phenyl glycidyl ether, alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, and the like. Examples of the non-reactive diluent include phthalate plasticizers such as benzyl alcohol, dioctyl phthalate, and butyl benzyl phthalate.

  Furthermore, examples of the epoxy resin filler include heavy calcium carbonate, light calcium carbonate, kaolin, talc, silica, titanium oxide, aluminum silicate, magnesium oxide, zinc oxide, and carbon black. Examples of the additive include silane coupling agents such as aminosilane and epoxysilane.

  Examples of the inorganic powder used in the present invention include silica sand, talc, calcium carbonate, and silica. The particle diameter of the inorganic powder is usually 10 to 500 μm, preferably 50 to 200 μm. The amount of the inorganic powder in the adhesive resin composition is usually 10 to 50% by weight, preferably 20 to 45% by weight.

  The reinforcing material sheet used in the present invention is, for example, a sheet in which reinforcing fibers and the like are buried in a synthetic resin and no fiber layer is present on the surface. Examples of synthetic resins include polyester resins, acrylic resins, epoxy resins, urethane resins, vinyl ester resins, and reinforcing fibers include inorganic fibers such as glass fibers, glass paper, and glass mats, vinylon fibers, carbon fibers, and aramid fibers. Organic fiber. In consideration of the balance between the elongation and strength of the reinforcing material sheet, vinylon fibers are preferable among the above-mentioned reinforcing fibers. Specific examples of the reinforcing material sheet used in the present invention include FRP sheets and FRP plates.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.

Example 1:
As an adherend to which the reinforcing material sheet is attached, a concrete plate is used in which a central portion of a reinforced concrete U-shaped lid (400 mm × 600 mm × 60 mm) is cored into a circular shape having a diameter of 100 mm.

  First, 100 parts by weight of a bisphenol A type epoxy resin (epoxy equivalent: 189 g / eq, manufactured by Dainippon Color Material Industries Co., Ltd .: trade name “PE-10”), 30 parts by weight of talc and a curing agent: metaxylenediamine base (Dainippon) An epoxy resin-impregnated primer containing 33 parts by weight of an epoxy resin impregnated product (trade name “PH-78” manufactured by Color Materials Co., Ltd.) was applied to a concrete plate with a roller at an adhesion amount of 0.25 kg / · and cured at 23 ° C. for 1 day.

  Next, 100 parts by weight of bisphenol A type epoxy resin (epoxy equivalent: 189 g / eq, manufactured by Dainippon Color Material Industries Co., Ltd .: trade name “PE-10”), 1,6-hexanediol diglycidyl ether (manufactured by Sakamoto Pharmaceutical Co., Ltd.) ) 18.3 parts by weight, fine powder silica (manufactured by Nippon Aerosil Co., Ltd .: trade name “Erosil # 380”) 4.8 parts by weight, silica sand 61 parts by weight (corresponding to 27.8% by weight in the composition) and curing agent: An epoxy resin composition (viscosity: 60,000 mPa · s (25 ° C .: BH type rotational viscometer)) containing 35.5 parts by weight of meta-xylenediamine base (Dainippon Color Material Co., Ltd .: trade name “PH-78”) , TI value: 5 (25 ° C. BH type rotational viscometer, 2 rotations / 20 rotations)) (adhesion amount: 1.0 kg / · (in terms of epoxy resin)) was applied with a trowel to form an adhesive resin layer Immediately reinforcement sheet The FRP sheet was pressed and attached by hand and cured at 23 ° C. for 1 day.

  The FRP sheet used was a sheet obtained by impregnating and curing a vinylon triaxial mesh with an acrylic resin and applying a urethane paint on the surface.

  Using the obtained FRP sheet affixed concrete pieces, a punching test was conducted with AG-50KNG (trade name) manufactured by Shimadzu Corporation in accordance with the standards of the Japan Highway Public Research Institute, and the strength and displacement of the reinforcing material sheet Was measured. As a result, a strength of a punching load of 3.0 KN was obtained at a displacement of 10 mm or more, and excellent peeling prevention performance was exhibited.

Claims (1)

  When repairing a defect on the ceiling or side of a concrete structure, the defect is smoothed using a base conditioner, and has a viscosity of 10,000 to 250,000 mPa · s and a TI value of 4 to 9. Repairing a concrete structure, characterized in that an adhesive resin composition is applied to the smoothed surface, and then a reinforcing material sheet having no fiber layer on the surface is applied to the application surface of the adhesive resin composition. Method.