KR101284604B1 - Method of repairing surface of concrete structures - Google Patents

Abstract

PURPOSE: A repair method for a surface of a concrete structure is provided to maximize repair effect by completely blocking inflow of moisture and oxygen to a surface after repair work. CONSTITUTION: A repair method for a structure of a concrete structure comprises as follows. A concrete surface on which repair work is needed is ground and is trimmed off. Primer is coated on the concrete surface. Paint composition is coated on the surface on which the primer is coated.

Description

Method of repairing surface of concrete structures

The present invention relates to a method for repairing the surface of a damaged concrete structure, and more particularly, it is possible to extend the surface repair effect by blocking the permeation of oxygen at the source, and at the same time to solve the problem of deterioration of weather resistance and surface strength The present invention relates to a method for repairing a concrete surface that is excellent and can maintain a repair effect for a long time.

Reinforced concrete structures are deteriorated in durability and usability in the long term due to deterioration of structures due to salt corrosion, neutralization, alkali aggregate reaction, chemical corrosion as well as corrosion expansion of steel due to penetration of water. As the deterioration of these structures continues, there is a risk of eventual collapse of the structures, so it is necessary to continuously manage and repair them.

Delamination or initial defects on the surface of the structure, or the occurrence of cracks facilitate the movement of deterioration factors, thereby facilitating the progress of deterioration. It is necessary to suppress and improve durability.

Therefore, in order to restore the section to its original performance and shape after removing the concrete part including deterioration factors such as deterioration factor of deterioration such as deterioration of concrete, corrosion of steel and other factors, It is general to carry out repair by construction.

Conventional repairing materials for the end face recovery mainly used cement-based mortar or polymer cement mortar, such conventional repairing materials to increase the strength or the initial construction for the purpose of suppressing the deterioration of the existing structure and improve the durability performance of the present Since most of them focused only on improving the adhesion performance, there was a problem of frequent repair work because the surface was easily damaged again soon after construction.

As an example, Korean Patent Laid-Open Publication No. 2006-0079447 proposes a method for preparing a mortar composition by adding a calcium sulfoaluminate (CSA) and a predetermined fine powder binder. However, the mortar composition prepared by using the material uses expensive Auyne-based cement, which causes an increase in construction cost and does not obtain sufficient results in terms of initial setting time and strength.

In addition, when it is installed by the existing repair method, since moisture and oxygen infiltrate into the minute gaps on the surface, corrosion of the reinforcing bars due to oxygen proceeds and concrete deterioration occurs due to moisture, which makes it difficult to maintain the surface repair effect for a long time. Because of this, there was a problem that the repair work should be carried out frequently.

Japanese Laid-Open Patent Publication No. H5-32935 discloses a coating composition which improves scratch resistance by introducing an acrylic copolymer to increase the hardness of a coating film, and Japanese Laid-Open Patent Publication No. 2000-297112 has a structure for promoting photopolymerization by ultraviolet irradiation. The coating composition which introduce | transduced and raises a crosslinking density, increases the hardness of a coating film, and improves scratch resistance is disclosed. However, if the crosslinking density is too high, the distortion during curing shrinkage may increase, resulting in poor adhesion or cracking.

In case of construction by conventional repair method, moisture and oxygen infiltrate into fine gaps on the surface, so corrosion of rebar is progressed by oxygen and concrete deterioration is caused by moisture. There was a problem that the construction should be carried out frequently.

The present invention was developed in consideration of the situation of the prior art as described above, it is possible to completely block the input of oxygen and moisture to the surface after repair work to maximize the repair effect can significantly extend the interval of repair work. In addition, it is to provide a surface repair method of the concrete structure that can significantly improve the repair effect by strengthening the weather resistance, water resistance and surface hardness of the concrete surface.

In order to achieve the above object,

(1) grinding the concrete surface to be repaired to refine the surface;

(2) applying a primer obtained by mixing a main body made of a modified epoxy resin and a curing agent made of an isocyanate compound on the concrete surface; And

(3) preparing the intermediate by reacting polyhydric alcohol and polybasic acid on the surface to which the primer is applied, and then reacting the prepared intermediate with polyamine to prepare an amine-modified unsaturated polyester resin, and then preparing the amine-modified unsaturated poly The ester resin was polymerized with dipentaerythritol polyacrylate and trimethylolpropane triacrylate to prepare a modified unsaturated polyester resin, and then a coating composition prepared by mixing the modified unsaturated polyester resin and the crosslinkable monomer prepared above. Step of applying

It provides a method of repairing the surface of the concrete structure comprising a.

Referring to the features and advantages of the repair method of the surface of the concrete structure according to the present invention.

1. First, by applying a primer that can completely block moisture and oxygen permeation on the surface of the mortar composition, it is possible to block the deterioration of concrete and reinforcing bars due to the permeation of oxygen or water to maintain the repair effect for a long time.

2. In addition, by applying a paint that can significantly improve weather resistance, water resistance, and surface strength on the outside of the primer, it is possible to extend the repair interval by maximizing the repair effect, so the economy is also excellent.

Hereinafter, the present invention will be described in more detail.

As described above, the present invention comprises the following three steps. In other words,

(1) grinding the concrete surface to be repaired to refine the surface;

(2) applying a primer obtained by mixing a main body made of a modified epoxy resin and a curing agent made of an isocyanate compound on the concrete surface; And

(3) preparing the intermediate by reacting polyhydric alcohol and polybasic acid on the surface to which the primer is applied, and then reacting the prepared intermediate with polyamine to prepare an amine-modified unsaturated polyester resin, and then preparing the amine-modified unsaturated poly The ester resin was polymerized with dipentaerythritol polyacrylate and trimethylolpropane triacrylate to prepare a modified unsaturated polyester resin, and then a coating composition prepared by mixing the modified unsaturated polyester resin and the crosslinkable monomer prepared above. Step of applying

Hereinafter, it will be described in detail by dividing each step.

1. Grinding the concrete surface

When cracks are generated in concrete due to deterioration in concrete structure, the compressive strength of concrete and tensile strength of reinforcing steel gradually decrease over time. Concrete exposed to cracks is neutralized and corrosion of reinforcing steel occurs. If such surface deterioration occurs through safety diagnosis and inspection, the surface of the concrete structure should be repaired before the deterioration to the interior of the concrete structure over time, which can prevent the large construction for reinforcement and increase the life of the building. I can keep it for a long time.

The grinding step is a process of grinding the deteriorated concrete surface before the uniformity of the concrete is generated and trimming the surface by using a machine until an undeteriorated portion comes out.

2. Application of primer

After grinding the concrete surface to finish it smoothly and drying, the primer obtained by mixing the main material consisting of a modified epoxy resin and a curing agent composed of an isocyanate compound is applied to the surface thinly.

In the present invention, the modified epoxy resin is a resin capable of adding a chelate ligand to the framework of a specially modified epoxy resin, having a hydroxyl value of 30 to 75 mm KOH, a molecular weight of 20,000 to 100,000 and a solid content of 20 to 75%. If the molecular weight is out of the above range, the resin falls outside the preferred viscosity range. If the solid content is too small, the composition of the paint is difficult. If the molecular weight is too large, the viscosity of the resin becomes high. When the hydroxyl value is less than 30 mm KOH, it is difficult to add the chelate ligand to the skeleton. When the hydroxyl value exceeds 75 mm KOH, the adhesion is lowered.

In the present invention, the isocyanate compound is a compound which undergoes a condensation reaction with the hydroxyl group of the modified epoxy resin to form a urethane bond, for example, as a diisocyanate compound such as hexamethylene diisocyanate, xylene diisocyanate and isophorone diisocyanate, It is preferable to use a substance having excellent vulcanization resistance.

In the present invention, the isocyanate compound is preferably diluted with a suitable solvent, stored in a separate container, and then sufficiently stirred immediately before use.

In the present invention, the above-mentioned modified epoxy resin and isocyanate compound as a curing agent are mixed immediately before use to prepare a primer agent. At this time, the mixing ratio is used in a ratio of subject: hardener = 1 to 10: 1, and the mixture is sufficiently stirred until it becomes uniform.

The primer agent may further include at least one selected from a solvent, a dispersant, an anti-settling agent, and a curing catalyst. As the solvent which can be used at this time, it is preferable to use aromatic hydrocarbons, for example, benzene, toluene, xylene and the like can be used.

The said primer can be used in mixture of a normal pigment. At this time, as a pigment that can be used, titanium dioxide, barium sulfate, talc and the like can be used. Titanium dioxide has excellent concealability and dispersibility, while talc or barium sulfate has excellent fillability and abrasiveness, and may be used by mixing one or more of these pigments in a required ratio.

The primer agent may further include a dispersant and an anti-settling agent that improve dispersibility and enhance stability. Dispersing agent and anti-settling agent is used to disperse during the manufacturing process of the primer to stabilize internal components such as pigment in the primer and to prevent sedimentation during storage. In the present invention, a known general dispersing agent can be used, and preferably an alkylammonium salt-based dispersant of a block copolymer having an acidic group is used. A known anti-settling agent may be used, and a modified hectorite anti-settling agent is preferably used.

In addition, a curing catalyst may be further added to the primer agent to accelerate the urethane reaction, which is the bond between the hydroxyl group of the modified epoxy resin and the isocyanate group of the curing agent. As the curing catalyst used in the present invention, at least one selected from the group consisting of tetramethyl butane diamine, bicyclooctane, dibutyl tin dilaurate, triethylenediamine, zinc octoate and calcium octoate can be used.

The primer agent according to the present invention can exhibit oxygen and moisture blocking and rust prevention functions even with only one coating, but it is preferable to repaint two to three times in order to achieve the optimal function. In the present invention, it is preferable that the primer is applied at 100 to 300 g / m < ² >, and the coating thickness is applied at a thickness of 100 to 300 mu m before the drying. The primer agent according to the present invention exhibits a water permeability of 0 and a water vapor permeability of 2 mg / m ² .24hr or less, thus exhibiting a perfect oxygen and water blocking function, thereby catching unstable rust during rusting, forming a stable chelation, and a terminal unreacted hydroxyl group. Acts to accelerate the formation of the coating film and to remove external influences during drying, and also to prevent rust generation by water by reacting with the crystal water in the rust. As a result, it is possible not only to prevent the external moisture or oxygen from penetrating into the concrete but also to prevent the rust generation due to moisture remaining in the concrete.

3. Coating composition application

In the present invention, after the primer is applied and dried, the coating composition prepared by mixing the modified unsaturated polyester resin and the crosslinkable monomer according to the present invention on the outer surface is further applied. The coating composition is prepared by reacting a polyalcohol and a polybasic acid to prepare an intermediate, and then reacting the prepared intermediate with a polyamine to prepare an amine-modified unsaturated polyester resin, and dipentaerythritol polyacrylate and trimethylolpropane triacrylate. By polymerizing to produce a modified unsaturated polyester resin and mixing them, the workability and surface strength are excellent, and weather resistance and water resistance are increased.

In the present invention, the polyhydric alcohol is ethylene glycol, propylene glycol, 2-butyl-2-ethyl-1,3 propanediol, neopentyl glycol, 1,3-butylene glycol, 1,6-hexane diol, 1,4 Preference is given to using one or a mixture of two or more selected from cyclohexane dimethylol, dihydroxy-2,2-dimethyl propyl ester, diethylene glycol, trimethylol ethane, trimethylol propane, glycerin and the like.

In addition, the polybasic acid may be an unsaturated polybasic acid and a saturated polybasic acid. The unsaturated polybasic acid is fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, tetrabromo anhydride, tetrachlorophthalic anhydride, chlorendic acid and hydroic acid anhydride. Any one or a mixture of two or more selected from (himic acid) may be used, and the saturated polybasic acid may be methyltetrahydrophthalic anhydride, phthalic acid, phthalic anhydride, halogenated anhydride, isophthalic acid, terephthalic acid, hexahydrophthalic acid, or hexahydrophthalic anhydride. , Hexahydroterephthalic acid, hexahydroisophthalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, sebacic acid, 1,12-dodecanoic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedica Any one or two selected from leric acid, 2,3-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid anhydride, 4,4'-biphenyldicarboxyl The mixtures can be used.

In the present invention, the polyamine may use one or more mixtures selected from 1,3-diaminopropane, methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, ethylenediamine, and diethylenetriamine. .

In the present invention, the dipentaerythritol polyacrylate may be selected from dipentaerythritol pentaacrylate, dipentaerythritol diacrylate and dipentaerythritol hexaacrylate.

Specifically, the intermediate in the present invention may be prepared by condensation reaction of 40 to 45% by weight of polyhydric alcohol, 20 to 30% by weight of saturated polybasic acid and 25 to 35% by weight of unsaturated polybasic acid. In addition, it is possible to obtain intermediates having a Gardner bubble point of N to O and an acid value of 8 to 14 mmKOH / g by measuring sampling time 60% IN SM in the reaction process and checking the reaction degree. In forming the intermediate, the condensation reaction temperature is preferably in the range of 150 to 200 ° C. to prevent gelation, and the bubble viscosity is N to O, and the acid value is in the range of 8 to 14 mmKOH / g in terms of dryness, water resistance, and adhesion. desirable.

Subsequently, the amine-modified unsaturated polyester resin may be synthesized by reacting with a reactant containing 0.1 to 10 parts by weight of polyamine based on 100 parts by weight of the intermediate synthesized above.

If the content of the polyamine is less than 0.1 part by weight, it may not impart sufficient stability to the particles of the modified unsaturated polyester resin to be produced, resulting in the formation of a coagulated product after the reaction. There is a possibility that the cured coating film is easily broken.

Subsequently, the amine-modified unsaturated polyester resin synthesized above is polymerized with dipentaerythritol polyacrylate and trimethylolpropane triacrylate to prepare a modified unsaturated polyester resin. The dipentaerythritol polyacrylate is 0.1 to 5 parts by weight, and the trimethylolpropane triacrylate is added to 15 to 25 parts by weight based on 100 parts by weight of the amine-modified unsaturated polyester resin to prepare a modified unsaturated polyester resin. It is preferable. When the content of trimethylolpropane triacrylate is less than 15 parts by weight or more than 25 parts by weight when the modified unsaturated polyester resin is produced, weatherability and surface hardness may be lowered, and when the content of the pentaerythritol polyacrylate is less than 0.1 When the amount is less than 5 parts by weight, the crosslinking property is lowered and the surface hardness is lowered. When the amount is more than 5 parts by weight, weatherability and thixotropy may be lowered.

The prepared unsaturated unsaturated polyester resin has a viscosity of 3 to 9 poise (25 ° C., Brookfield viscometer), 80 to 90% nonvolatile content, and an acid value of 5 to 13 mmKOH / g. When the viscosity, the nonvolatile content and the acid value of the modified unsaturated polyester resin are within the above ranges, they are preferable in terms of surface hardness, curability, water resistance and thixotropy.

The coating composition in the present invention is a range of 60 to 70% by weight of the modified unsaturated polyester resin prepared above, 10 to 20% by weight of crosslinkable monomers and various additives which are conventionally added in the paint field, without impairing the object of the present invention. From 15 to 25% by weight. Preferably the crosslinkable monomer comprises trimethylolpropanetriacrylate and methyl methacrylate in a ratio of 1 to 1.5: 1.

In preparing the coating composition, if the modified unsaturated polyester resin content is less than 60% by weight, thixotropy and adhesion are inferior, and if it exceeds 70% by weight, surface hardness and leveling property are inferior.

In addition, when the content of the crosslinkable monomer is less than 10% by weight, the surface hardness, heat resistance and curability are inferior, and when the content is more than 20% by weight, the cured coating film may be fragile and there may be a problem in that adhesion and irregularity are inferior.

The coating composition of the present invention includes various additives in a range that does not impair the effects of the present invention. As the additive, additives such as thixotropic agents such as silica, pigments, defoamers and organic modulators are used.

Moreover, it can harden | cure by normal temperature hardening or heat hardening by adding an promoter in the range which is common in manufacturing coating composition and does not affect resin color.

Examples of the curing accelerator in the present invention include metal soaps such as cobalt naphthenate, cobalt octylate, zinc octylate, vanadium octylate, copper naphthenate and barium naphthenate, vanadium acetylacetate, cobaltacetyl acetate, and iron acetyl. Metal chelates such as acetonate, aniline, N, N-dimethylaniline, N, N-diethylaniline, p-toluidine, N, N-dimethyl-p-toluidine, N, N-bis (2-hydroxyethyl ) -p-toluidine, 4- (N, N-dimethylamino) benzaldehyde, 4- [N, N-bis (2-hydroxyethyl) amino] benzaldehyde, 4- (N-methyl-N-hydroxyethylamino Benzaldehyde, N, N-bis (2-hydroxypropyl) -p-toluidine, N-ethyl-m-tol

N, N-substituted anilines, N, such as uidine, triethanolamine, m-toluidine, diethylenetriamine, pyridine, phenylmorpholine, piperidine, N, N-bis (hydroxyethyl) aniline, diethanolaniline Amines such as, N-substituted-p-toluidine, 4- (N, N-substitutedamino) benzaldehyde and the like can be used. As for the said hardening accelerator, the range of 0.1-5 weight part is suitable with respect to 100 mass parts of modified unsaturated polyester resins. Preferably, cobalt naphthenate (Co-Naph) may be used. If the content of the curing accelerator is 0.1% by weight or less, the curability is inferior, and if it exceeds 5% by weight, the cured coating film is fragile and the thixotropic property is inferior.

In the present invention, the coating composition is preferably applied in a thickness of 10 to 100㎛, it is preferable to paint 1 to 3 times.

In the above description, the primer and the coating composition are applied after grinding the damaged concrete surface. However, when the degree of surface damage is relatively large but the chipping process is not necessary, the mortar is applied to the concrete surface after the step (1). The process may further include. In this case, the mortar may use a general mortar, but it is more preferable to use a fast mortar for the efficiency of the work.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by the following examples.

[Example]

Production Example 1 Preparation of Primer

After mixing 30 parts by weight of a modified epoxy resin (weight average 45%, hydroxyl group average 50mmKOH) with a weight average molecular weight of 50,000 and 5 parts by weight of a curing agent (hexamethylene diisocyanate and diluent), 35 parts by weight of barium sulfate as a pigment, a solvent As the xylene, 19 parts by weight, a dispersant and a sedimentation inhibitor were added to prepare a primer. The primer was used by mixing the main agent and the curing agent immediately before use.

Production Example 2 Coating Composition

Into a 5-liter flask equipped with a nitrogen gas introduction tube, a stirrer, a thermometer, a cooling capacitor, a bead decanter, and a dropping funnel, 682 g of neopentyl glycol and 493 g of isophthalic acid were added thereto, and the temperature was raised to 165 DEG C over 2 hours in a nitrogen gas atmosphere. . At this time, when the condensation water is generated while the esterification reaction proceeds, the condensation water is removed through the condenser line while maintaining for 2 hours. After removing the condensed water, the mixture was heated up again for 2 hours, gradually stirred and heated, and heated at 215 ° C. Sampling was carried out every hour during the reaction to determine the solid acid value. When the solid acid value reached 2 mmKOH / g, the reaction was stopped and cooled to 100 ° C. 114g of propylene glycol and 544g of fumaric acid were further added at 100 ° C, and the temperature was raised to 165 ° C over 2 hours in a nitrogen atmosphere. At this time, when the condensation water was generated while the esterification reaction proceeded, the condensation water was removed through the condenser line while maintaining it for 1 hour. After the condensed water was generated, the mixture was heated up again for 3 hours, heated to 215 ° C, and reacted. In the course of reaction, 60% IN SM was sampled every hour to check the degree of reaction. It cooled by Gardner bubble viscosity N and acid value 11 mmKOH / g, and obtained the intermediate body.

After removing the bead decanter from the flask, equipped with a dropping funnel, 79 g of polyamine (1,3-diaminopropane) was added and stabilized at 90 ℃ to prepare an amine-modified unsaturated polyester resin. Subsequently, 59 g of prepared dipentaerythritol hexaacrylate and 462 g of trimethylolpropane triacrylate were added to the dropping funnel, and then added dropwise while paying attention to polymerization for a constant time for 2 hours, and the viscosity was 6 poise, 85% of nonvolatile matter, and acid value. 67.7 g of 9 mm KOH / g modified unsaturated polyester resin was synthesized.

67.7 g of the modified unsaturated polyester resin synthesized above, 2.5 g of fumed silica and 16.9 g of a pigment (titanium oxide, TMC-A100, Dongwoo TMC) were mixed and completely ground using a roller. Then, 0.6 g of a defoaming agent (ODS Co., Ltd., Airex 945), 0.3 g of an organic thixotropic agent, 14.3 g of trimethylolpropane triacrylate, and 11.9 g of methyl methacrylate were added to prepare a coating composition. . A coating composition was prepared by adding N, N-Diethylacetoacetamide (Sigma-Aldrich) that does not affect the resin color and cobalt naphthenate (Sigma-Aldrich) for adjusting the curing time.

Production Example 3 Coating Composition

682 g of propylene glycol and 493 g of isophthalic acid were added to a 5-liter flask equipped with a nitrogen gas introduction tube, a stirrer, a thermometer, a cooling capacitor, a bead decanter, and a dropping funnel, and the temperature was raised to 180 ° C. over 2 hours in a nitrogen gas atmosphere. At this time, when the condensation water is generated while the esterification reaction proceeds, the condensation water is removed through the condenser line while maintaining for 2 hours. After removing the condensed water, the mixture was heated up again for 2 hours, gradually stirred and heated up, and heated at 230 ° C. Sampling was carried out every hour in the course of the reaction to determine the solid acid value, the reaction was stopped when the solid acid value reaches 2.5 mmKOH / g and cooled to 100 ℃. 114g of propylene glycol and 544g of fumaric acid were further added in sequence at 100 ° C, and the temperature was raised to 180 ° C over 2 hours in a nitrogen atmosphere. At this time, when the condensation water was generated while the esterification reaction proceeded, the condensation water was removed through the condenser line while maintaining it for 1 hour. After the condensed water was generated, the mixture was heated up again for 3 hours, heated to 230 ° C, and reacted. In the course of reaction, 60% IN SM was sampled every hour to check the degree of reaction. It cooled by Gardner bubble viscosity N and acid value 13 mmKOH / g, and obtained the intermediate body. After removing the bead decanter from the flask, equipped with a dropping funnel, 79 g of polyamine (1,3-diaminopropane) was added and stabilized at 90 ℃ to prepare an amine-modified unsaturated polyester resin. Subsequently, 59 g of prepared dipentaerythritol hexaacrylate and 462 g of trimethylolpropane triacrylate were added to the dropping funnel, and then added dropwise while paying attention to polymerization for a constant time for 2 hours, and the viscosity was 6 poise, 82% nonvolatile content, acid value. A 10 mmKOH / g modified unsaturated polyester resin was synthesized.

67.7 g of the modified unsaturated polyester resin synthesized above, 2.5 g of fumed silica, and 16.9 g of a pigment (titanium oxide, TMC-A100, DongwooTMC) were mixed and completely ground using a roller. Then, 0.6 g of a defoaming agent (ODS Co., Ltd., Airex 945), 0.3 g of an organic thixotropic agent, 14.3 g of trimethylolpropane triacrylate, and 11.9 g of methyl methacrylate were added to prepare a coating composition. A coating composition was prepared by adding N, N-Diethylacetoacetamide (Sigma-Aldrich) that does not affect the resin color and cobalt naphthenate (Sigma-Aldrich) for adjusting the curing time.

(Comparative Production Example 1) Coating Composition

An intermediate was prepared in the same manner as in Preparation Example 2, the bead decanter was removed from the flask, a dropping funnel was installed, and 479 g of styrene was added thereto, followed by stabilization at 90 ° C. to prepare an unsaturated polyester resin. Thereafter, 521 g of styrene prepared in advance was added to the dropping funnel, and then added dropwise while paying attention to polymerization for a predetermined time for 2 hours. Synthesized. 67.7 g of the modified unsaturated polyester resin synthesized above, 2.5 g of fumed silica and 16.9 g of a pigment (titanium oxide, TMC-A100, Dongwoo TMC) were mixed and completely ground using a roller. Thereafter, 0.6 g of a defoaming agent (ODS Co., Ltd., Airex 945), 0.3 g of an organic thixotropic agent, and 26.2 g of styrene were added to prepare an organic / inorganic coating composition. A coating composition was prepared by adding N, N-Diethylacetoacetamide (Sigma-Aldrich) that does not affect the resin color and cobalt naphthenate (Sigma-Aldrich) for adjusting the curing time.

(Comparative Production Example 2) Coating Composition

An amine-modified unsaturated polyester resin was prepared in the same manner as in Preparation Example 2. Thereafter, 521 g of trimethylolpropanetriacrylate prepared in advance was added to a dropping funnel, and then added dropwise while paying attention to polymerization for a predetermined time for 2 hours, and a modified unsaturated poly with a viscosity of 6 poise, 85% of nonvolatile matter, and an acid value of 9 mmKOH / g. 67.7 g of ester resin were synthesized. 67.7 g of the modified unsaturated polyester resin synthesized above, 2.5 g of fumed silica and 16.9 g of a pigment (titanium oxide, TMC-A100, Dongwoo TMC) were mixed and completely ground using a roller. Then, 0.6 g of a defoaming agent (ODS Co., Ltd., Airex 945), 0.3 g of an organic thixotropic agent, 14.3 g of trimethylolpropane triacrylate, and 11.9 g of methyl methacrylate were added to prepare a coating composition. A coating composition was prepared by adding N, N-Diethylacetoacetamide (Sigma-Aldrich) that does not affect the resin color and cobalt naphthenate (Sigma-Aldrich) for adjusting the curing time.

Example 1

After grinding the damaged concrete surface to remove the damaged portion and smoothing the surface, the primer prepared in Preparation Example 1 was once coated with a thickness of 100 µm and dried, and then the coating composition prepared in Preparation 2 was used. In addition, after coating to 100㎛ thickness dried to complete the repair work.

[Example 2]

After grinding the damaged concrete surface to remove the damaged part and smoothing the surface, the primer prepared in Preparation Example 1 was once coated with a thickness of 100 µm and dried, and then the coating composition prepared in Preparation 3 was used. In addition, once coated with a thickness of 100㎛ dried to complete the repair work.

[Example 3]

After grinding the damaged concrete surface to remove the damaged portion and smoothing the surface, the primer prepared in Preparation Example 1 was once coated with a thickness of 100 µm and dried, and then the coating composition prepared in Preparation 2 was used. In addition, after coating twice with a thickness of 100㎛ dried to complete the repair work.

Example 4

After grinding the damaged concrete surface to remove the damaged part and smoothing the surface, the primer prepared in Preparation Example 1 was once coated with a thickness of 100 µm and dried, and then the coating composition prepared in Preparation 3 was used. In addition, after coating twice with a thickness of 100㎛ dried to complete the repair work.

Comparative Example 1

The same process as in Example 1 was carried out except that the surface was coated with a commercially available general epoxy resin primer (Sikafloor, 1004K), and only the coating was performed using the coating composition prepared in Comparative Preparation Example 1.

Comparative Example 2

The same process as in Example 1 was carried out except that the surface was coated with a commercially available general epoxy resin primer (Sikafloor, 1004K), and only the coating was performed using the coating composition prepared in Comparative Preparation Example 2.

Performance evaluation

(1) evaluation of temperature and humidity changes

As a result of measuring the temperature and humidity change in the interior after the maintenance work carried out through the above Examples and Comparative Examples, the results shown in Table 1 were obtained.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Temperature change Humidity change Temperature change Humidity change Temperature change Humidity change Temperature change Humidity change Temperature change Humidity change Temperature change Humidity change 1 time +10 +0.03 +15 +0.05 +9 +0.03 +9 +0.02 +25 +0.12 +30 +0.21 Episode 2 +11 +0.04 +13 +0.04 +8 +0.02 +8 +0.03 +30 +0.15 +32 +0.23 Condition Outside: temperature 80 ℃, relative humidity 100%
Internal (initial): test starts at 20 ° C and 20% relative humidity
Measurement of internal temperature and humidity changes after 48 hours

From the results of Table 1, when using the repair method according to the present invention it can be seen that there is almost no change in temperature and humidity change moisture blocking performance is very good.

(3) weather resistance evaluation

It was measured for 200 hours according to ASTM G 155. Measurement conditions are as follows.

1) Light Sourse: 6500w Xenone Arc, Irradance: 0.35W / ㎡

2) B.P.T. : 63 ℃ ± 3 ℃, Humidity: 50% ± 5% RH

3) Inner / Outer Filter: Borosilicate / borosilicate

4) Spray Cycle: 18 minutes light irradiation and water spray after 102 minutes light irradiation

(4) surface hardness evaluation

Pencil hardness: measured according to KS D 6711.

(5) water resistance evaluation

The time at which surface deformation (cracks, blisters, etc.) occur continuously at 90 ° C. hot water was measured.

The results of evaluating weather resistance, surface hardness and water resistance in Example 1-4 and Comparative Example 1-2 are shown in Table 2.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Weatherability (white) E1.2 △ E2.1 △ E1.9 △ E2.0 △ E3.9 △ E4.5 Surface hardness 4H 4H 3H 4H 1H 1H Water resistance 420hr 430 hr 450hr 460 hr 190hr 250hr

Using the repair method according to the present invention from the results of Tables 1 to 2 is excellent in oxygen and water blocking performance, and also excellent in weather resistance, surface hardness and water resistance, so that it is possible to efficiently repair the concrete surface, It can be seen that the effect can be maintained for a long time.

Claims (10)

(1) grinding the concrete surface to be repaired to refine the surface;
(2) As a resin capable of adding a chelate ligand to the modified epoxy resin skeleton on the concrete surface, a main body and an isocyanate composed of a modified epoxy resin having a hydroxyl value of 30 to 75 mmKOH, a molecular weight of 20,000 to 100,000 and a solid content of 20 to 75%. The curing agent consisting of the compound is mixed in a weight ratio of 1 to 10: 1, and a solvent, a dispersant, a modified hectorite antisettling agent selected from benzene, toluene and xylene, tetramethylbutanediamine, bicyclooctane, dibutyltin dilaurate, triethylene It is obtained by mixing one or more curing catalysts selected from the group consisting of diamine, zinc octoate and calcium octoate with pigments selected from titanium dioxide, barium sulfate and talc. The water permeability is 0 and the water vapor permeability is 2 mg / m ² .24hr or less. Applying the primer represented by 100 ~ 300g / m ^{2 In the} step before drying to a thickness of 100 ~ 300㎛; And
(3) preparing the intermediate by reacting polyhydric alcohol and polybasic acid on the surface to which the primer is applied, and then reacting the prepared intermediate with polyamine to prepare an amine-modified unsaturated polyester resin, and then preparing the amine-modified unsaturated poly The ester resin was polymerized with dipentaerythritol polyacrylate and trimethylolpropane triacrylate to prepare a modified unsaturated polyester resin, and then a coating composition prepared by mixing the modified unsaturated polyester resin and the crosslinkable monomer prepared above. Step of applying
Repair method of the surface of the concrete structure comprising a.
delete The method for repairing a concrete structure surface according to claim 1, wherein the isocyanate compound of (2) is at least one selected from hexamethylene diisocyanate, xylene diisocyanate and isophorone diisocyanate.
delete The polyhydric alcohol of claim 3, wherein the polyhydric alcohol of (3) is ethylene glycol, propylene glycol, 2-butyl-2-ethyl-1,3 propanediol, neopentyl glycol, 1,3-butylene glycol, 1,6- Using any one or a mixture of two or more selected from hexane diol, 1,4-cyclohexane dimethylol, dihydroxy-2,2-dimethyl propyl ester, diethylene glycol, trimethylol ethane, trimethylol propane, glycerin The method of repairing the surface of the concrete structure characterized in that.
The polybasic acid of (3) is a maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, tetrahydrophthalic acid, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, tetrabromophthalic anhydride, tetra Unsaturated polybasic acid or methyltetrahydrophthalic anhydride, phthalic anhydride, phthalic anhydride, phthalic anhydride, isophthalic acid, consisting of any one or two or more mixtures selected from chlorophthalic anhydride, chlorendic acid and hemic acid Terephthalic acid, hexahydrophthalic acid, hexahydrophthalic anhydride, hexahydroterephthalic acid, hexahydroisophthalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, sebacic acid, 1,12-dodecanoic acid, 2,6-naphthalenedica Leric acid, 2,7-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid anhydride, 4,4'-biphenyldicar Which repair process of the concrete surface which is characterized by using one or a saturated polybasic acid consisting of a mixture of two or more that are selected from the chamber.
The content of polyamine of (3) is 0.1 to 10 parts by weight, 1,3-diaminopropane, methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, ethylenediamine, diethylene A process for repairing a concrete structure surface, characterized by using one or more mixtures selected from triamines.
The concrete according to claim 1, wherein the dipentaerythritol polyacrylate of (3) is selected from dipentaerythritol pentaacrylate, dipentaerythritol diacrylate and dipentaerythritol hexaacrylate. How to repair the surface of the structure.
The unsaturated polyester resin of the above (3) has a viscosity of 3 to 9 poise (25 ° C., Brookfield viscometer), a nonvolatile content of 80 to 90%, and an acid value of 5 to 13 mmKOH / g. Repair method for the surface of the concrete structure, characterized in that.
The method for repairing a concrete structure surface according to claim 1, wherein the crosslinkable monomer of (3) uses a mixture of trimethylolpropanetriacrylate and methyl methacrylate.