JP2017115539A - Repairing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a repairing method with which a part of water leak crack generated on a concrete structure may be simply repaired for a short time to stop the water leak while keeping use of the concrete structure.SOLUTION: The present invention has a feature that comprising a temporal water stopping step where at a water leaking crack part on a concrete structure, temporal water stop agent containing main agent (A) containing urethane prepolymer having terminal isocyanate group and curing agent (B) containing tertiary amine and a tin compound is applied so as to temporarily stop water, and a repair-finishing step where reactive finishing agent is applied to the crack part so as to execute repair finishing.SELECTED DRAWING: None

Description

  The present invention relates to a repair method.

  In concrete structures such as tunnels, viaducts, and concrete buildings, cracks may occur due to the expansion and contraction of concrete due to rain and temperature changes, and water leakage may occur from these cracks.

  Therefore, as a repair method for cracked parts, Patent Document 1 discloses a resin emulsion (liquid A) obtained by emulsifying a petroleum resin and an acrylic resin in water with polyvinyl alcohol, and a urethane composition (liquid B) containing a urethane prepolymer. A temporary water stop agent is proposed in which the resin emulsion and the urethane composition have a mass ratio (A liquid: B liquid) of 100: 5 to 100: 20.

Japanese Patent No. 5300162

  However, the above-mentioned temporary waterproofing agent has a problem that it is necessary to form a perforation in concrete in order to inject the water-stopping material into the cracked part causing water leakage, and it takes time to repair the cracked part of concrete. Have.

  The present invention provides a repair method capable of easily performing a water stop repair in a short time on a cracked portion accompanying water leakage generated in a concrete structure while continuing to use the concrete structure.

The present invention includes a main agent (A) containing a urethane prepolymer having an isocyanate group at a terminal and a curing agent (B) containing a tertiary amine and a tin compound at a cracked portion with water leakage in a concrete structure. A temporary water stopping step of applying a temporary water stopping agent to the cracked portion to temporarily stop water;
And a repair finishing step in which a reactive finish is applied to the cracked portion for repair finishing.

  Since the present invention has the configuration as described above, it is possible to simply and quickly stop water at a cracked portion accompanying water leakage at room temperature, while continuing to use a concrete structure. In addition, it is possible to smoothly perform the water stop operation of the water leakage portion.

  The present invention includes a main agent (A) containing a urethane prepolymer having an isocyanate group at a terminal and a curing agent (B) containing a tertiary amine and a tin compound at a cracked portion with water leakage in a concrete structure. It includes a temporary water stopping step of applying a temporary water stopping agent to the cracked portion and temporarily stopping water, and a repair finishing step of applying a reactive finishing agent to the cracked portion and finishing the repair.

  In addition, it does not specifically limit as a concrete structure, For example, concrete structures, such as concrete buildings, such as a building, a tunnel, a viaduct, etc. are mentioned.

(Temporary water stop process)
First, a temporary structure containing a main agent (A) containing a urethane prepolymer having an isocyanate group at a terminal and a curing agent (B) containing a tertiary amine and a tin compound at a cracked portion with water leakage in a concrete structure. A temporary water stop process is performed in which a water stop agent is applied to the cracked portion to temporarily stop the water.

  In the repair method described above, a temporary water-stopping agent is applied to a cracked portion accompanying water leakage without the need to newly form a perforation or a groove for waterstopping at the cracked portion accompanying water leakage in the concrete structure.

  The temporary waterproofing agent includes a main agent (A) containing a urethane prepolymer having an isocyanate group at the terminal, and a curing agent (B) containing a tertiary amine and a tin compound.

  The main agent (A) contains a urethane prepolymer having an isocyanate group at the terminal. As the urethane prepolymer having an isocyanate group at the terminal, conventionally known urethane prepolymers can be used. For example, the urethane prepolymer can be obtained by reacting polyisocyanate and polyol in an excess amount.

  As the polyisocyanate, a polyisocyanate conventionally used in the production of a urethane prepolymer having an isocyanate group at the terminal can be used, but 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, and A mixture of 4,4′-diphenylmethane diisocyanate and 2,4′-diphenylmethane diisocyanate is preferred, and 4,4′-diphenylmethane diisocyanate is more preferred.

  As a polyol, the polyisocyanate conventionally used for manufacture of the urethane prepolymer which has an isocyanate group at the terminal can be used, However, A polyoxyalkylene polyol is preferable.

  Examples of the polyoxyalkylene polyol include polyoxypropylene polyol and polyoxybutylene polyol, polyoxypropylene polyol is preferable, polyoxypropylene diol and polyoxypropylene triol are more preferable, and polyoxypropylene diol is particularly preferable. .

  The number average molecular weight of the polyoxyalkylene polyol is preferably 1000 to 3000. When the number average molecular weight of the polyoxyalkylene polyol is 1000 or more, the cured coating film of the temporary waterproofing agent has excellent elongation, smoothly follows the expansion and expansion of the concrete after repair, and The water stop state can be maintained over a long period of time. When the number average molecular weight of the polyoxyalkylene polyol is 3000 or less, the viscosity of the temporary water stop agent can be suppressed to improve the handleability of the temporary water stop agent, and the cured film of the temporary water stop agent is excellent. It has a high mechanical strength and can maintain the water-stopped state of the cracked portion over a long period of time.

  The number average molecular weight of the polyoxyalkylene polyol is a value in terms of polystyrene measured by GPC (gel permeation chromatography) method. Specifically, 6 to 7 mg of polyoxyalkylene polyol was sampled, and after the collected polyoxyalkylene polyol was supplied to a test tube, the test tube contained 0.05% by mass of BHT (dibutylhydroxytoluene). A diluted solution is prepared by adding a DCB (orthodichlorobenzene) solution and diluting the polyoxyalkylene polymer to a concentration of 1 mg / mL.

  The dilution liquid is shaken for 1 hour at a rotation speed of 25 rpm at 145 ° C. using a dissolution filter, and the polyoxyalkylene polyol is dissolved in the o-DCB solution containing BHT to obtain a measurement sample. Using this measurement sample, the number average molecular weight of the polyoxyalkylene polyol can be measured by the GPC method.

The number average molecular weight in the polyoxyalkylene polyol can be measured, for example, with the following measuring device and measurement conditions.
Product name "HLC-8121GPC / HT" manufactured by TOSOH
Measurement conditions Column: TSKgelGMHHR-H (20) HT x 3
TSKguardcolumn-HHR (30) HT x 1
Mobile phase: o-DCB 1.0 mL / min
Sample concentration: 1 mg / mL
Detector: Bryce refractometer
Reference material: Polystyrene (Molecular weight: 500-8420000, manufactured by TOSOH)
Elution conditions: 145 ° C
SEC temperature: 145 ° C

  The average functional group number of the polyoxyalkylene polyol is preferably 2.0 to 2.5, and more preferably 2.0 to 2.2. If the average functional group number of the polyoxyalkylene polyol is 2.0 or more, the mechanical strength of the cured coating film of the temporary water-stopping agent can be improved, and the water-stopping state of the cracked portion can be maintained over a long period of time. . If the average number of functional groups of the polyoxyalkylene polyol is 2.5 or less, the cured coating film of the temporary waterproofing agent has excellent elongation, smoothly follows the expansion and expansion of the concrete after repair, and cracks It is possible to maintain the water-stopping state of the place for a long period of time.

  The hydroxyl value of the polyoxyalkylene polyol is such that the temporary water-stopper has an appropriate viscosity and excellent handleability, and the cured film of the temporary water-stopper has excellent mechanical strength and extensibility, Since the water stop state of the cracked part can be maintained over a long period of time, 8 to 300 mgKOH / g is preferable, and 28 to 120 mgKOH / g is more preferable. The hydroxyl value of polyoxyalkylene polyol refers to a value measured according to JIS K1557-1.

  The viscosity at 23 ° C. of the urethane prepolymer having an isocyanate group at the terminal is preferably 1 to 400 Pa · s, more preferably 5 to 200 Pa · s. When the viscosity of the urethane prepolymer having an isocyanate group at the terminal is 1 to 400 Pa · s at 23 ° C., the main agent (A) can be smoothly applied to the cracked portion regardless of the water leakage pressure. In addition, the viscosity at 23 ° C. of the urethane prepolymer having an isocyanate group at the end was determined according to JIS Z8803 by leaving it at 23 ° C. for 24 hours or more and then using a B-type viscometer. It can be measured under the conditions of 7 rotors and 10 rpm.

  The main agent (A) may contain an inorganic filler in order to adjust the viscosity of the urethane prepolymer having an isocyanate group at the terminal. The inorganic filler is not particularly limited, and examples thereof include calcium carbonate, talc and mica, and calcium carbonate is preferable.

  As for content of the inorganic filler in a main ingredient (A), 10-200 mass parts is preferable with respect to 100 mass parts of urethane prepolymer which has an isocyanate group at the terminal, and 50-150 mass parts is more preferable. When the content of the inorganic filler is within the above range, the coating properties of the main agent (A) or the temporary water stop agent are improved.

  1.0-1.8 are preferable and, as for the specific gravity of a main ingredient (A), 1.2-1.7 are more preferable. When the specific gravity of the main agent (A) is 1.0 or more, the cracked portion can be temporarily stopped effectively. When the specific gravity of the main agent (A) is 1.5 or less, the coating properties of the main agent (A) or the temporary water-stopper improve.

  In the main agent (A), an adhesion-imparting agent, a physical property modifier, a plasticizer, a thixotropic agent, a dehydrating agent (a storage stability improving agent), a tackifier, and a dripping are added as necessary within the range not impairing the physical properties thereof. An inhibitor, an ultraviolet absorber, an antioxidant, a flame retardant, a colorant and the like may be contained.

  The viscosity of the main agent (A) at 23 ° C. is preferably 20 to 400 Pa · s, and more preferably 50 to 200 Pa · s. When the viscosity at 23 ° C. of the main agent (A) is 20 to 400 Pa · s, the main agent (A) can be smoothly applied to cracked portions regardless of the water leakage pressure. In addition, the viscosity at 23 ° C. of the main agent (A) of the temporary water-stopper was determined according to JIS Z8803 by leaving it at 23 ° C. for 24 hours or more and then using a B-type viscometer. It can be measured under the conditions of 7 rotors and 10 rpm.

  The curing agent (B) contains a tertiary amine and a tin compound. The tertiary amine is not particularly limited. For example, 2,4,6-tris (dimethylaminomethyl) phenol, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N '-Tetramethylpropylenediamine, N, N, N', N ", N" -pentamethyldiethylenetriamine, N, N, N ', N ", N" -pentamethyl- (3-aminopropyl) ethylenediamine, N, N , N ′, N ″, N ″ -pentamethyldipropylenetriamine, N, N, N ′, N′-tetramethylguanidine, 1,3,5-tris (N, N-dimethylaminopropyl) hexahydro-S— Triazine, 1,8-diazabicyclo [5.4.0] undecene-7, triethylenediamine, N, N, N ′, N′-tetramethylhexamethylenediamine, N, N -Dimethylpiperazine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, bis (2-dimethylaminoethyl) ether, 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, 1 -Dimethylaminopropylimidazole etc. are mentioned, 2,4,6-tris (dimethylaminomethyl) phenol is preferred. In addition, a tertiary amine may be used independently or 2 or more types may be used together.

  In the curing agent (B), the content of the tertiary amine is preferably 1 to 20 parts by mass, and 2 to 18 parts by mass with respect to 100 parts by mass of the urethane prepolymer having an isocyanate group at the terminal in the main agent (A). Is more preferable, and 4 to 15 parts by mass is particularly preferable. When the content of the urethane prepolymer having an isocyanate group at the terminal is 1 part by mass or more, the temporary water-stopping agent is quickly cured, and temporary water-stopping at a cracked portion can be performed in a short time. When the content of the urethane prepolymer having an isocyanate group at the terminal is 10 parts by mass or less, the pot life of the temporary water stopping agent can be set to an appropriate time, and the handleability of the temporary water stopping agent is improved.

  The tin compound is not particularly limited. For example, dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis (dibutyltin lauric acid) oxide, dibutyltin bis (acetylacetonate), dibutyltin bis (Monoester maleate), tin octylate, dibutyltin octoate, dioctyltin oxide, dibutyltin bis (triethoxysilicate), bis (dibutyltin bistriethoxysilicate) oxide, dibutyltin oxybisethoxysilicate, and 1,1, 3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distanoxane and the like can be mentioned, and 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distanoxane is preferred. In addition, a tin compound may be used independently or 2 or more types may be used together.

  In the curing agent (B), the content of the tin compound is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the tertiary amine because the curing rate of the temporary water stopping agent can be easily adjusted. -15 mass parts is more preferable, and 8-12 mass parts is especially preferable.

  The viscosity at 23 ° C. of the curing agent (B) is preferably 1 to 400 Pa · s, more preferably 5 to 200 Pa · s. When the viscosity at 23 ° C. of the curing agent (B) is 1 to 400 Pa · s, the temporary water stop agent can be smoothly applied to the cracked portion regardless of the leakage pressure. In addition, the viscosity at 23 ° C. of the hardening agent (B) of the temporary water-stopper was determined according to JIS Z8803 by leaving it at 23 ° C. for 24 hours or more and then using a B-type viscometer. It can be measured under the conditions of 7 rotors and 10 rpm.

  In the curing agent (B), an adhesion-imparting agent, a physical property adjusting agent, a filler, a plasticizer, a thixotropic agent, a dehydrating agent (storage stability improving agent), and an adhesive are added within the range that does not impair the physical properties. An imparting agent, an anti-sagging agent, an ultraviolet absorber, an antioxidant, a flame retardant, a colorant and the like may be contained.

  In the repair method, first, a temporary water stopping step is performed in which a temporary water stop agent is applied to a cracked portion of a concrete structure, the temporary water stop agent is cured to form a cured coating film, and temporary water stopping is performed at the cracked portion. Do. In applying the temporary water stop agent to the cracked portion, (1) the main agent (A) and the curing agent (B) may be mixed in advance in a general manner, and then the temporary water stop agent may be applied to the cracked portion. (2) After applying the main agent (A) to the cracked part, the curing agent (B) may be applied to the cracked part (the surface to which the main agent (A) is applied) where the main agent (A) is applied. (2) is preferable because it can be smoothly applied to the cracked portion without curing (A).

  Application | coating to the crack location of a temporary water stop agent is performed by the general purpose point, for example, the method of apply | coating a temporary water stop agent to a crack location using a brush etc. is used. The curing time (curing time) after applying the temporary water stop agent to the cracked portion is preferably 10 to 120 seconds, and more preferably 30 to 60 seconds.

(Repair finishing process)
In the above repair method, after the temporary water stopping step, a repair finishing step is performed in which a reactive finish is applied to the cracked portion where the temporary water stopping agent is applied and repaired.

  In the above repair method, the cracked part is temporarily stopped by the repair finishing process, and then the reactive finish is applied to the cracked part and repaired, so the cured coating of the reactive finish is applied to the cracked part. It can be applied reliably, and the cracked part can be reliably stopped.

  The reactive finishing agent is not particularly limited as long as it can be applied to a wet cracked part and can adhere firmly to the cracked part, but includes a main agent (C) containing an epoxy resin and a polyamine curing agent. What contains a hardening | curing agent (D) and whose specific gravity after mixing the said main ingredient (C) and the said hardening | curing agent (D) is 1.2-2.5 is preferable.

  It does not specifically limit as an epoxy resin which comprises the main ingredient (C). The epoxy resin is obtained by polymerizing a monomer having two or more epoxy groups in one molecule. Examples of the monomer include glycidyl ethers, glycidyl esters, glycidyl amines, linear aliphatic epoxides, and alicyclic epoxides. An epoxy resin may be used independently or 2 or more types may be used together.

  Examples of glycidyl ethers include diglycidyl ether of bisphenol, polyglycidyl ether of phenol novolac, alkylene glycol, or diglycidyl ether of polyalkylene glycol.

  Examples of the diglycidyl ether of bisphenol include diglycidyl ethers of dihydric phenols such as bisphenol A, bisphenol F, bisphenol AD, bisphenol S, tetramethylbisphenol A, and tetrabromobisphenol A.

  Examples of the polyglycidyl ether of phenol novolak include polyglycidyl ethers of novolak resins such as phenol novolak, cresol novolak, and brominated phenol novolak.

  Examples of the diglycidyl ether of alkylene glycol or polyalkylene glycol include diglycidyl ethers of glycols such as polyethylene glycol, polypropylene glycol, and butanediol.

  Examples of glycidyl esters include diglycidyl ester of hexahydrophthalic acid, diglycidyl ester of dimer acid, and the like. Examples of glycidylamines include tetraglycidyldiaminodiphenylmethane, tetraglycidylmetaxylylenediamine, triglycidylaminophenol, and triglycidyl isocyanurate.

  Examples of the linear aliphatic epoxides include epoxidized polybutadiene and epoxidized soybean oil. Examples of the alicyclic epoxides include 3,4-epoxy-6-methylcyclohexyl methyl carboxylate, 3,4-epoxycyclohexyl methyl carboxylate, and the like.

  As an epoxy resin, what polymerized the monomer of glycidyl ethers, glycidyl amines, or glycidyl esters is preferable, and what polymerized the monomer of glycidyl ethers is more preferable.

  As the glycidyl ethers, diglycidyl ethers of bisphenols are preferable, and diglycidyl ethers of bisphenol A or bisphenol F are more preferable.

  The main agent (C) may contain an aggregate from the viewpoint of improving the coatability of the reactive finish and the mechanical strength of the cured coating film. Examples of such aggregates include ordinary Portland cement, calcium carbonate, silica sand, river sand, crushed stone material, crushed porcelain, crushed glass, and glass beads. Aggregates may be used alone or in combination of two or more.

  10-300 mass parts is preferable with respect to 100 mass parts of epoxy resins of a main ingredient (C), and, as for content of the aggregate in a main ingredient (C), 20-200 mass parts is more preferable. When the aggregate content is 10 to 300 parts by mass, the coating properties of the reactive finish are excellent, and the adhesive strength of the cured coating film of the reactive finish is improved.

  100-1000 Pa.s is preferable and, as for the viscosity in 23 degreeC of a main ingredient (C), 300-800 Pa.s is more preferable. A reactive finishing agent can be smoothly apply | coated to a crack location as the viscosity in 23 degreeC of a main ingredient (C) is 100-1000 Pa.s. In addition, the viscosity at 23 ° C. of the main component (C) of the reactive finish was determined according to JIS Z8803 by leaving it at 23 ° C. for 24 hours or more and then using a B-type viscometer. It can be measured under the conditions of 7 rotors and 10 rpm.

  The polyamine-based curing agent constituting the curing agent (D) is not particularly limited. For example, polyethyleneamine containing primary and secondary amines generated by reaction of ethylene dichloride or ethylene oxide with ammonia. , Modified products in which the polyethylene amine is adducted with an epoxy resin or an alkylene epoxide, modified aliphatic polyamines in which the polyethylene amine is polycondensed with an aliphatic or phenol / formaldehyde (Mannich), and one or more amines are directly attached to a saturated cyclic product. And a polyaminoamide type curing agent which is a reaction product of a polymerized fatty acid and an aliphatic amine, and a polyaminoamide type curing agent is preferable.

  The polyaminoamide-based curing agent is a compound having a plurality of active amino groups and one or more amide groups in the molecule. For example, a polymerized fatty acid (usually a dimer acid formed from a natural unsaturated fatty acid). ) And an aliphatic / polyalkylene polyamine condensate produced by condensation reaction of polyalkylene polyamines with a mixture of other fatty acids added as necessary.

  Polymerized fatty acids are industrially non-catalytic or fatty acids containing many unsaturated components such as linoleic acid and linolenic acid from natural tall oil, soybean oil, safflower oil, etc., or clay, alumina silicate, etc. It is synthesized by heating in the presence of a catalyst. Examples of the polyalkylene polyamines include polyethylene polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.

  Aliphatic / polyalkylene polyamine condensates are commercially available, for example, from ACI JAPAN under the trade names “Ancamide 500”, “Ancamide 502” and “Ancamide 502”. The modified alicyclic polyamine-based curing agent is commercially available from ACI JAPAN under the trade name “Ancamine 1618”, for example. The modified aliphatic polyamine is commercially available, for example, from ACI JAPAN under the trade name “Casamide 2221”.

  In the curing agent (D), the content of the polyamine curing agent is preferably 50 to 150 parts by mass, more preferably 70 to 120 parts by mass with respect to 100 parts by mass of the epoxy resin of the main agent (C). When the content of the polyamine curing agent is 50 parts by mass or more, the reactive finishing agent is quickly cured, and repair finishing of the cracked portion can be performed in a short time. When the content of the polyamine-based curing agent is 150 parts by mass or less, the pot life of the reactive finish can be set to an appropriate time, and the handleability of the reactive finish is improved.

  Further, the curing agent (D) may contain a curing accelerator such as a tertiary amine and boron trifluoride as necessary. The content of the curing accelerator in the curing agent (D) is preferably 2 to 10% by mass with respect to the polyamine curing agent. When the content of the curing accelerator is 2 to 10% by mass, the tensile adhesion strength of the cured coating film of the reactive finish is improved, and the water stop state of the cracked portion can be maintained over a long period of time. In addition, the initial curability can be improved and the cracked portion can be repaired promptly.

  The hardener (D) may contain an aggregate in order to improve the coatability. Examples of such aggregates include calcium carbonate, silica sand, river sand, crushed stone material, crushed porcelain, crushed glass, and glass beads. Aggregates may be used alone or in combination of two or more.

  20-200 mass parts is preferable with respect to 100 mass parts of polyamine type hardening | curing agents, and, as for content of the aggregate in a hardening | curing agent (D), 30-150 mass parts is more preferable. When the aggregate content is 20 to 200 parts by mass, there is almost no dripping of the reactive finish, the reactive finish is excellent in coating properties, and the cured coating film of the reactive finish is cracked. It adheres firmly to the location, making the water stop at the crack location stronger.

  The viscosity of the curing agent (D) at 23 ° C. is preferably 100 to 1000 Pa · s, and more preferably 200 to 800 Pa · s. A reactive finishing agent can be smoothly apply | coated to a crack location as the viscosity in 23 degreeC of a hardening | curing agent (D) is 20-400 Pa.s. The viscosity of the curing agent (D) of the reactive finish at 23 ° C. was determined in accordance with JIS Z8803 by leaving it at 23 ° C. for 24 hours or more and then using a B-type viscometer. It can be measured under the conditions of 7 rotors and 10 rpm.

  The specific gravity of the mixture obtained by mixing the main agent (C) and the curing agent (D) is preferably 1.2 to 2.5, and more preferably 1.4 to 2.0. If the specific gravity of the mixture is 1.2 or more, the cracked portion can be effectively repaired and finished. When the specific gravity of the mixture is 2.5 or less, the coatability of the reactive finish is improved.

  In the repair finishing process, a reactive finish is applied to the cracked area where the temporary water stop agent was applied in the temporary water stopping process, the reactive finish is cured to form a cured coating film, and repairing the water stop at the cracked area. Finish.

  When a reactive finish containing a main agent (C) and a curing agent (D) is used as a reactive finish, the main agent (C) and the curing agent (D) are mixed and then applied to the cracked portion. The

  Application of the reactive finishing agent to the cracked portion is performed in a general manner, and for example, a method of applying the reactive finishing agent to the cracked portion using a brush or the like is used. The curing time (curing time) after applying the reactive finish to the cracked portion is preferably 1 to 6 hours, and more preferably 2 to 4 hours.

  As described above, the repair method performs a temporary water stop of the cracked part in the water stop process, and then applies a reactive finish to the cracked part to form a cured coating film of the reactive finish. A cured coating film of the reactive finish can be reliably formed in the cracked portion. Therefore, the cracked portion of the concrete structure is in a state of being reliably filled with the cured coating film of the temporary water-stopper and the reactive finish, and the water-stop state can be reliably maintained for a long period of time. it can.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

The temporary water stop agent and reactive finish used in the examples will be described.
(Urethane prepolymer having an isocyanate group at the end)
67.7 parts by mass of polypropylene glycol having a number average molecular weight of 2000 (polyoxypropylene diol, trade name “Diol-2000” manufactured by Mitsui Takeda Chemical, average functional group number: 2.0, hydroxyl value: 56 mgKOH / g) After that, it was fed into a stirrer equipped with a thermometer. Next, 32.3 parts by mass of 4,4′-diphenylmethane diisocyanate (MDI) was added to the stirrer and reacted at 90 ° C. for 3 hours under a nitrogen stream to obtain a urethane prepolymer having an isocyanate group at the terminal. . The content of the terminal isocyanate group in the urethane prepolymer having an isocyanate group at the terminal was 8.0% by mass. The viscosity of the urethane prepolymer having an isocyanate group at the terminal at 23 ° C. was 10 Pa · s.

[Adjustment of main agent (A) of temporary water-stopper]
Precipitated calcium carbonate (trade name “CCR” manufactured by Shiroishi Kogyo Co., Ltd.) was prepared and dried under an atmosphere of 90 ° C. for 4 hours. 100 parts by mass of precipitated calcium carbonate was added to 100 parts by mass of a urethane prepolymer having an isocyanate group at the terminal to prepare a main ingredient of a temporary water-stopper (specific gravity: 1.5, viscosity at 23 ° C .: 200 Pa · s). .

[Adjustment of temporary water-stopper curing agent (B)]
10 parts by mass of 2,4,6-tris (dimethylaminomethyl) phenol (trade name “Ancamine K54” manufactured by Air Products Japan) as a tertiary amine and 1,1,3,3-tetrabutyl-1 as a tin compound , 3-dilauryloxycarbonyl-distannoxane (product name “Neostan U-130” manufactured by Nitto Kasei Co., Ltd.) 1 part by weight is mixed with a hardening agent (viscosity at 23 ° C .: 10 Pa · s) of a temporary water-stopper. Produced.

[Preparation of Reactive Finishing Agent (C)]
Add 50 parts by weight of ordinary Portland cement to 100 parts by weight of bisphenol A type epoxy resin (trade name “jER828” manufactured by Mitsubishi Chemical Corporation), which is a polymer of bisphenol A diglycidyl ether, and knead and finish for 1 hour with a planetary mixer. A main agent (viscosity at 23 ° C .: 350 Pa · s) was prepared.

[Preparation of Reactive Finishing Curing Agent (D)]
100 parts by mass of an aliphatic / polyalkylene polyamine condensate (“Ancamide 502” manufactured by ACI JAPAN) as a polyaminoamide-based curing agent and 60 parts by mass of precipitated calcium carbonate (CCR (manufactured by Shiraishi Kogyo Co., Ltd.)) are added and mixed uniformly. Thus, a finishing curing agent (viscosity at 23 ° C .: 250 Pa · s) was produced.

  The specific gravity of the mixture obtained by mixing the main component (C) of the reactive finish and the curing agent (D) was 1.4.

Example 1
Two rectangular parallelepiped mortar blocks measuring 70 mm long × 50 mm wide × 20 mm high were prepared. The mortar block was immersed in water at room temperature for 24 hours. The two mortar blocks were arranged so that their 70 mm × 20 mm surfaces face each other in parallel with an interval of 0.5 mm. In the gap, a spacer was provided in order to maintain a gap of 0.5 mm.

  In this state, about two mortar blocks, the opening part of the clearance gap in which the 20-mm-long sides of the mortar block were formed facing each other was water-tightly sealed with an adhesive tape. Therefore, a gap having an opening between the sides having a length of 70 mm was formed between the two mortar blocks.

  100 parts by mass of the main ingredient (A) of the temporary waterproofing agent and 10 parts by mass of the curing agent (B) were mixed uniformly. In the mixture of temporary waterproofing agents, 18.2 parts by mass of the tertiary amine was contained with respect to 100 parts by mass of the urethane prepolymer having an isocyanate group at the terminal.

  A mixture of a temporary water stop agent was applied in a width of 50 mm, a length of 70 mm, and a thickness of 1 mm so as to fill a gap formed between the mortar blocks.

  100 parts by mass of the main component (C) of the reactive finishing agent and 100 parts by mass of the curing agent (D) were mixed uniformly. In the mixture of reactive finishes, 100 parts by mass of a polyaminoamide-based curing agent was contained with respect to 100 parts by mass of the bisphenol A type epoxy resin.

  After 60 seconds have passed after applying the temporary water stop agent to the mortar block, the width 70 mm and the length of the temporary water stop agent on the cured coating film so as to completely cover the cured film of the temporary water stopping agent. A mixture of reactive finishes was applied with a thickness of 70 mm and a thickness of 1 mm.

  Immediately after applying the reactive finish, invert the two mortar blocks and fill the gap by supplying water from the opening on the side opposite to the side where the temporary water-stopper and reactive finish are applied. I let you. Thereafter, the presence or absence of water leakage from the cured coating film of the reactive finish was visually observed, and the results of the water leakage test are shown in Table 2.

  Next, after removing water supplied to the gaps between the mortar blocks, the mortar blocks were left for 7 days in an atmosphere of 23 ° C. and 50% relative humidity.

Thereafter, a 40 mm × 40 mm jig was attached to the cured coating film of the reactive finishing agent formed on the mortar block, and the planar tensile strength was measured under a 23 ° C. atmosphere and a pulling speed of 3 mm / min. The plane tensile strength is preferably 0.4 N / mm ² or more. The results are shown in Table 2.

(Example 2)
Without mixing the main agent (A) and the curing agent (B) of the temporary water stopping agent, the width of the temporary water stopping agent is 50 mm wide, 70 mm long, and 1 mm thick so as to fill the gap formed between the mortar blocks. After applying 100 parts by mass of the main agent (A), 10 parts by mass of the curing agent (B) was sprayed on the main agent (A) in the form of a mist. Except for the above, the presence or absence of water leakage and the plane tensile strength were measured in the same manner as in Example 1.

(Comparative Example 1)
Existence of water leakage and planar tensile strength were measured in the same manner as in Example 1 except that the reactive finishing agent was not applied onto the cured coating film of the temporary water-stopper.

(Comparative Example 2)
The presence or absence of water leakage and the plane tensile strength were measured in the same manner as in Example 1 except that only the reactive water-stopping agent was used without applying the temporary water-stopper.

Claims (5)

Temporary still water containing a main agent (A) containing a urethane prepolymer having an isocyanate group at the terminal and a curing agent (B) containing a tertiary amine and a tin compound at a cracked portion with water leakage in a concrete structure. A temporary water stopping step of applying an agent to the cracked portion and temporarily stopping water;
And a repair finishing step in which a reactive finish is applied to the cracked portion for repair finishing.   The reactive finishing agent contains a main agent (C) containing an epoxy resin and a curing agent (D) containing a polyamine curing agent, and after mixing the main agent (C) and the curing agent (D). 2. The repair method according to claim 1, wherein the specific gravity is 1.2 to 2.5.   The repair method according to claim 1 or 2, wherein the viscosity of the main agent (A) at 23 ° C is 20 to 400 Pa · s.   In a temporary water stop process, after apply | coating a main agent (A) to a crack location, a hardening | curing agent (B) is apply | coated to the application surface of the said main agent (A), The any one of Claims 1-3 characterized by the above-mentioned. Repair method described in.   The repair method according to any one of claims 1 to 4, wherein the specific gravity of the main agent (A) is 1.0 to 1.5.