KR101311699B1 - Composite for repairing concrete structure and repairing method of concrete structure using the composite - Google Patents

Abstract

PURPOSE: A concrete structure repair composition is provided to offer excellent acid-resistance, flame interruption performance, mobility, elasticity, adhesive force, heat resistance, and durability by using a cement composite in a specific composition and a revival state resin. CONSTITUTION: A concrete structure repair composition contains 15-70 wt% of cement composite, 25-70 wt% of fine aggregate, 0.01-15 wt% of revival state resin, and 0.1-15 wt% of water. The revival state resin contains 50-95 wt% of styrene-butadiene resin powder, 0.1-20 wt% of polyether sulfone resin powder, 0.1-20 wt% of polymethyl metacrylate resin, and 0.1-20 wt% of sodium polyacrylate resin. The fine aggregate contains 50-95 wt% of silica sand, 1-30 wt% of mica, and 1-20 wt% of vermiculite. The cement composite contains 15-70 wt% of normal Portland cement, 15-55 wt% of blast furnace slag powder, 5-30 wt% of fly ash, 1-20 wt% of silica fume, 1-20 wt% of anhydrous gypsum, 1-15 wt% of calcium sulfoaluminate, 0.1-10 wt% of alumina cement, 0.01-10 wt% of zinc oxide, 0.01-10 wt% of zeolite, and 0.01-10 wt% of rice husk ash.

Description

Composition for repairing concrete structures with excellent acid resistance and durability and repair method for concrete structures using the same {Composite for repairing concrete structure and repairing method of concrete structure using the composite}

The present invention relates to a repair composition and a repair method of a concrete structure using the same, and more particularly, a cement composition having excellent acid and flame resistance, fluidity, elasticity, adhesion, acid resistance, heat resistance and durability, and an excellent reemulsifying resin. By the flame retardancy, strength, high fluidity, elasticity, adhesiveness, acid resistance, heat resistance and durability excellent composition for repairing concrete structures and a method for repairing concrete structures using the same.

The deterioration of the performance of the concrete structure means that the concrete fails to exert its original function and deteriorates its characteristics over time due to neutralization, salt corrosion, frost, chemical erosion, alkali aggregate reaction, fatigue, weathering,

In general environment, there is a small probability of chemical corrosion problem, and organic matter contained in domestic sewage, etc. reacts by bacteria to produce sulfate ions, which in turn erodes concrete, or is caused by acid substances such as hot spring zone or acid rain. In most cases, the concrete structure is corroded by the corrosion of reinforced concrete structures located in the marine environment. Structures subject to chemical corrosion include marine concrete, chemical plants, food plants, associated structures such as barn floors, soil contamination and underground structures in hot springs, sewage-related sewer pipes and covered structures.

On the other hand, in order to prevent the salt damage of marine concrete structures, the Concrete Standard Specification recommends the use of mixed cements such as blast furnace slag cement, fly ash cement, or medium heat Portland cement as specified in KS L 5201. .

In addition, in the case of marine concrete constructed at a location severely affected by seawater, the quality of requirements cannot be secured only with cement-based materials. Therefore, the main penetration of polymer cement concrete and polymer concrete using cement and polymer, or chloride ion It is proposed to use polymer-impregnated concrete impregnated with synthetic resin with voids in the concrete path.

However, some of these materials can not be practically used in the construction site due to the problems of concrete manufacturing, economics and constructability, and practically there are few applications to marine structures. In addition, when blast furnace slag cement or fly ash cement is used in marine concrete, blast furnace slag or fly ash is less responsive than cement, so the penetration resistance of chloride ions is lower than that of cement-only concrete until cement is fully hydrated. It is known.

Therefore, there is a need for a practical and universally usable cement composition for marine structures that can impart flame retardancy to marine concrete regardless of when it is exposed to the marine environment.

The problem to be solved by the present invention is the strength and durability, especially acid and flame resistance by using an environmentally friendly cement composition excellent in acid and flame resistance and re-emulsification resin having excellent fluidity, elasticity, adhesion, acid resistance, heat resistance and durability It is excellent in preventing concrete corrosion caused by chemical erosion such as marine concrete structure, underwater concrete structure, concrete structure under harsh environment, sewage pipe, etc., which can significantly reduce the maintenance cost. The present invention provides a composition for repairing concrete structures having excellent thermal insulation and strength, and excellent durability against acid, salt, and the like, by using silicate silica, mica and vermiculite mixed with excellent effects.

The present invention comprises 15 to 70% by weight of cement composition, 25 to 70% by weight of fine aggregate, 0.01 to 15% by weight of reemulsifying resin and 0.1 to 15% by weight of water, wherein the reemulsifying resin is to improve the strength and adhesion 50 to 95% by weight of styrene-butadiene resin powder, 0.1 to 20% by weight of polyethersulfone resin powder for improving adhesion and heat resistance, 0.1 to 20% by weight of polymethyl methacrylate resin for improving acid resistance and alkali resistance It provides a composition for repairing concrete structures, comprising 0.1 to 20% by weight of sodium polyacrylate resin for improving strength and durability.

The cement composition is usually 15 to 70% by weight of Portland cement, 15 to 55% by weight of blast furnace slag, 5 to 30% by weight of fly ash, 1 to 20% by weight of silica fume, 1 to 20% by weight of gypsum, calcium sulfoaluminate 1 to 15% by weight, 0.1 to 10% by weight alumina cement, 0.01 to 10% by weight zinc oxide, 0.01 to 10% by weight zeolite and 0.01 to 10% by weight rice husk ash.

The cement composition may further comprise 0.01 to 10% by weight of titanium oxide.

The fine aggregate may comprise 50 to 95% by weight of silica siliceous sand, 1 to 30% by weight of mica and 1 to 20% by weight of vermiculite.

The re-emulsifying resin may further include 0.01 to 5% by weight of a mixture of polyamide and methyl cellulose in a weight ratio of 0.1 to 0.8: 0.2 to 0.9 in order to provide a cohesive force and material separation prevention to form a stable concrete structure. Can be.

In addition, the re-emulsifying resin may further comprise 0.01 to 10% by weight of acrylamide emulsion.

In addition, the re-emulsification resin may further comprise 0.1 to 40% by weight of ethylene vinyl acetate resin.

In addition, the re-emulsifying resin may further comprise 0.1 to 30% by weight of styrene-acrylic ester resin.

In addition, the present invention, the step of removing impurities, latencies and deteriorated parts of the concrete structure with a hand water jet or a high pressure water washer, the step of primer treatment on the removed portion, and repairing the concrete structure on the primer treated top It provides a method for repairing a concrete structure, comprising the step of restoring the cross-section by pouring the composition for the surface and the surface-recovered result of the restored cross-section and applying a surface protective agent.

The primer treatment may include at least one selected from the group consisting of styrene-butadiene latex, polyacrylic ester, acrylic, ethylvinyl acetate, methyl methacrylate, and silane-based compounds. The surface protecting agent may be at least one selected from the group consisting of styrene-butadiene latex, polyacrylic ester , Acrylic, ethylvinyl acetate, methyl methacrylate, and silane-based compounds may be used.

The deteriorated portion may further include removing the lower portion of the reinforcing bar and rust-protecting the exposed reinforcing bar before the primer treatment.

According to the present invention, by using a cement composition having excellent acid and flame resistance and a reemulsifying resin having excellent fluidity, elasticity, adhesion, acid resistance, heat resistance and durability, the acid resistance, flame resistance, flowability, elasticity, adhesion, strength and durability are greatly increased. There is an effect to be improved.

In addition, by using cement composition and reemulsifying resin, it is excellent in strength and durability, especially acid and flame resistance, which can prevent concrete corrosion due to chemical erosion of marine concrete structures, water structures, underground structures, chemical plant floors, sewer pipes, etc. Therefore, it is possible to significantly reduce the maintenance costs used for this.

In addition, by using a fine aggregate in which mica, silica siliceous sand, vermiculite, etc., which are excellent in far-infrared effect are used, excellent heat insulation and strength, and excellent durability against acid, salt and the like.

The composition for repairing concrete structures of the present invention has excellent compressive strength, flexural strength, and adhesive strength, and can be easily applied to various existing methods as well as sewage facilities having a lot of acidic substances, and mechanized construction such as spraying construction is easy. Since it is possible, there are many effects, such as improving work efficiency and having economical construction.

Hereinafter, preferred embodiments according to the present invention will be described in detail. However, it should be understood that the following embodiments are provided so that those skilled in the art will be able to fully understand the present invention, and that various modifications may be made without departing from the scope of the present invention. It is not.

Concrete structure repairing composition according to a preferred embodiment of the present invention, the cement composition comprises 15 to 70% by weight, fine aggregate 25 to 70% by weight, re-emulsified resin 0.01 to 15% by weight and water 0.1 to 15% by weight.

Environmentally friendly cement compositions with excellent acid and flame resistance are commonly used in Portland cement, blast furnace slag powder, fly ash, silica fume, anhydrous gypsum, calcium sulfoaluminate, alumina cement, zinc oxide, zeolite and rice husk ash. It may include.

Environmentally friendly cement composition with excellent acid and flame resistance is usually 15 to 70% by weight of Portland cement, 15 to 55% by weight of blast furnace slag, 5 to 30% by weight of fly ash, 1 to 20% by weight of silica fume, 1 to 20% of anhydrous gypsum. Wt%, calcium sulfoaluminate 1-15 wt%, alumina cement 0.1-10 wt%, zinc oxide 0.01-10 wt%, zeolite 0.01-10 wt% and rice husk ash 0.01-10 wt% It is preferable to include.

It is preferable that the ordinary Portland cement uses cement conforming to the KS standard. The ordinary portland cement is preferably contained 15 to 70% by weight in the cement composition.

The blast furnace slag powder is used for improving latent hydraulic characteristics, long-term strength development and durability. When the weight ratio of the blast furnace slag powder is increased, the early strength is lowered, but the long-term strength development and durability are increased. The blast furnace slag powder is preferably contained 15 to 55% by weight in the cement composition.

The fly ash is used to enhance latent hydraulic properties, long-term strength development and durability. When the weight ratio of the fly ash is increased, the early strength is lowered, but the long-term strength development and durability are increased. The fly ash is preferably contained 5 to 30% by weight in the cement composition.

The silica fume is used to improve latent hydraulic properties, long-term strength and durability. When the weight ratio of the silica fume is increased, the early strength is lowered, but the long-term strength development and durability are increased. The silica fume is preferably contained in the cement composition 1 to 20% by weight.

The anhydrous gypsum (CaSO ₄ ) reacts with the components in the cement, in particular C ₃ A ( ₃ CaO.Al ₂ O ₃ ), to initially produce ettringite (AFt phase, C ₃ A · ₃ CaSO ₄ · 32 H ₂ O) The produced etrinzate decreases in its amount as the hydration proceeds, or a part thereof is transferred to monosulfate (AFm phase, C ₃ A · CaSO ₄ · 12H ₂ O). When a large amount of anhydrous gypsum is added as in the present invention, etrinzite is sufficiently generated from the beginning to densify the structure of the cement, thereby increasing penetration resistance to chloride ions in the early age. In addition, in the case of general cement, the produced ethrinzite is mainly present only at the initial stage, but in the cement composition of the present invention, since a sufficient amount of gypsum is added, ethrinzite is also present in a part of the long-term age or part of ethrin Zites may be generated continuously. The nitrite produced in this way increases the penetration resistance to chlorides even in the long term by densely filling the pores in the concrete structure. The anhydrous gypsum is preferably contained in the cement composition 1 to 20% by weight.

The calcium sulfoaluminate is an inorganic quick-hard mineral material that is added to increase the hydration reactivity and inhibit cracking, and when mixed with cement by reacting with water to produce ettringite hydrate in an instant. When it is possible to obtain a good compressive strength in a short time. The calcium sulfo aluminate is preferably contained 1 to 15% by weight in the cement composition. When the weight ratio of the calcium sulfo aluminate increases, it exhibits fast curing characteristics. When the content of the calcium sulfo aluminate is less than 1% by weight, the effect of improving strength and preventing cracks may be weak, and the content of the calcium sulfo aluminate is increased. When it exceeds 15% by weight, good physical properties can be obtained due to the fast curing property, but the manufacturing cost is high, which is not economical.

The alumina cement is used to improve chemical resistance, in particular acid resistance. The alumina cement is preferably contained in 0.1 to 10% by weight in the cement composition. When the weight ratio of the alumina cement is increased, it exhibits fast curing characteristics, and when the content of the alumina cement is less than 0.1% by weight, the effect of improving chemical resistance and acid resistance may be weak, and when the content of the alumina cement is more than 10% by weight. Due to the fast curing properties, good physical properties can be obtained, but the manufacturing cost is high, it is not economical.

The zinc oxide can be used for antiseptic and antibacterial functions. The zinc oxide is preferably contained in the cement composition 0.01 to 10% by weight. When the weight ratio of zinc oxide is increased, the antifouling performance is exhibited. When the content of zinc oxide is less than 0.01 wt%, the effect of preservation, antibacterial and antifouling performance may be weak. When the content of zinc oxide is more than 10 wt% Is not economical because the intensity is lowered and the manufacturing cost is increased.

The zeolite serves as an adsorbent as a porous inorganic material. The zeolite is preferably contained in the cement composition 0.01 to 10% by weight. Increasing the weight ratio of the zeolite indicates the viscosity improving performance, when the content of the zeolite is less than 0.01% by weight, the viscosity improving effect may be weak, when the content of the zeolite exceeds 10% by weight of workability is lowered Higher manufacturing costs are not economical.

The rice husk ash is used for latent hydraulic properties, long-term strength development and durability enhancement. When the weight ratio of the rice husk ash is increased, early strength is lowered, but long-term strength expression and durability are increased. The rice husk ash is preferably contained in the cement composition 0.01 to 10% by weight.

The cement composition may further include titanium oxide. The titanium oxide can be used for antiseptic and antimicrobial functions. The titanium oxide is preferably contained in the cement composition 0.01 to 10% by weight. When the weight ratio of the titanium oxide is increased, the antifouling performance is exhibited. When the content of the titanium oxide is less than 0.01 wt%, the effect of preservation, antibacterial and antifouling performance may be weak. When the content of the titanium oxide is more than 10 wt% Is not economical because the intensity is lowered and the manufacturing cost is increased.

In addition, the cement composition may further include a water reducing agent. The water reducing agent is used to improve the strength and durability by reducing the water-cement ratio of the cement composition. The water reducing agent may be a polycarbonate-based, melamine-based or naphthalene-based fluidizing agent. Melamine-based or naphthalene-based sensitizers are less effective in improving strength and durability than polycarboxylic acid sensitizers, do not have a significant effect on reducing water-cement ratios, and when mixed with re-emulsifying resins, foaming occurs, resulting in poor compatibility. There are disadvantages. Therefore, it is preferable to use a polycarboxylic acid type reducing agent, and it is preferable that 0.01-2 weight% is contained in the said cement composition.

In addition, the cement composition may further include a retardant. The retarder can be used to ensure workability for a certain period of time and to delay rapid curing. The retardant is preferably contained in the cement composition 0.01 to 2% by weight. As the delaying agent, generally well known substances can be used. Examples thereof include saccharides such as glucose, glucose, texturin and dextran, acids or salts thereof such as gluconic acid, malic acid, citric acid and citric acid, Or a salt thereof, a phosphonic acid or a derivative thereof, and a polyhydric alcohol such as glycerin.

The fine aggregate may include silica siliceous sand, mica and vermiculite. The fine aggregate preferably contains 50 to 95% by weight of siliceous silica sand, 1 to 30% by weight of mica and 1 to 20% by weight of vermiculite. In general, aggregate is classified into fine aggregate and coarse aggregate. Coarse aggregate means aggregate exceeding 5 mm in diameter. Hereinafter, fine aggregate refers to aggregate having a particle size of 5 mm or less in comparison with coarse aggregate. By using mica, silica siliceous sand, vermiculite mixed with excellent far-infrared effect, excellent thermal insulation and strength, and excellent durability against acid, salt and the like.

It is preferable that the silica siliceous sand has particle size No. 4 to No. 8 (0.05 to 2.0 mm). If the particle size of the siliceous silica sand is larger than this, there is a fear that the fluidity of the composition for repairing the concrete structure may be lowered, and when it is smaller than this, the workability of the composition for repairing the concrete structure may be reduced. Silica siliceous sand is preferably contained 50 to 95% by weight in the fine aggregate.

The mica is used to increase the biological activity effect of the far infrared rays are released from the composition for repairing concrete structures as aggregates that are far infrared rays are emitted. The mica is preferably contained 1 to 30% by weight in the fine aggregate.

The vermiculite is a non-toxic, odorless, porous, lightweight, low thermal conductivity, environmentally friendly material used to improve the non-combustible and thermal insulation effect of the composition for repairing concrete structures. The vermiculite is preferably contained 1 to 20% by weight in the fine aggregate.

The re-emulsifying resin is used to improve pot life, workability, elasticity, flowability, strength, adhesion, acid resistance, heat resistance and durability, and styrene-butadiene resin powder for improving strength and adhesion, improving adhesion and heat resistance Polyethersulfone resin powder, polymethyl methacrylate resin for improving acid resistance and alkali resistance, and sodium polyacrylate resin for improving strength and durability.

The re-emulsifying resin comprises 50 to 95% by weight of styrene-butadiene resin powder, 0.1 to 20% by weight of polyethersulfone resin powder, 0.1 to 20% by weight of polymethyl methacrylate resin and 0.1 to 20% by weight of sodium polyacrylate resin. It is desirable to.

The re-emulsifying resin is preferably contained in 0.01 to 15% by weight in the composition for repairing concrete structures. When the content of the re-emulsifying resin exceeds 15% by weight, the viscosity is lowered, so that material separation is likely to occur, delaying the hydration reaction, lowering early compressive strength, and lowering price competitiveness. When the content of the reemulsifying resin is less than 0.01% by weight, pot life, workability, elasticity, flowability, strength, adhesion, acid resistance, heat resistance, and durability improvement effects may be weak.

The styrene-butadiene resin powder is used to improve strength and adhesion. The styrene-butadiene resin powder is preferably contained in the re-emulsification resin 50 to 95% by weight, when the content of the styrene-butadiene resin powder is less than 50% by weight the effect of improving the bonding strength, adhesion and durability between the inorganic matters In addition, when the content of the styrene-butadiene resin powder exceeds 95% by weight, it is difficult to expect further adhesion and durability improvement effect.

The polyethersulfone resin powder is used to improve adhesion and heat resistance. The polyethersulfone resin powder is preferably contained in the re-emulsification resin 0.1 to 20% by weight. When the content of the polyethersulfone resin powder exceeds 20% by weight, the performance of the composition for repairing concrete structures is improved, but the price competitiveness This may fall, if the content of the polyethersulfone resin powder is less than 0.1% by weight of the workability of the composition for repairing the concrete structure is improved but the effect of improving the adhesion and heat resistance may be weak.

The polymethyl methacrylate resin is used to improve the workability and ductility properties by reducing the viscosity of the composition for repairing concrete structures. In addition, the polymethyl methacrylate resin is excellent in acid and alkali resistance to improve the strength. The polymethyl methacrylate resin is preferably contained in the re-emulsification resin 0.1 to 20% by weight. When the content of the polymethyl methacrylate resin exceeds 20% by weight, the performance of the composition for repairing concrete structures is improved. Price competitiveness may be lowered, the acid resistance and strength improvement effect may be weak if the content of the polymethyl methacrylate resin is less than 0.1% by weight.

The sodium polyacrylate resin is used to improve the strength and durability of the composition for repairing concrete structures. The sodium polyacrylate resin is preferably mixed with 0.1 to 20% by weight in the re-emulsification resin, when the content of the sodium polyacrylate resin exceeds 20% by weight, the performance of the composition for repairing the concrete structure is improved, but the price competitiveness If the content of the sodium polyacrylate resin is less than 0.1% by weight, the strength and durability improvement effects may be weak.

The reemulsifying resin may further include a mixture of polyamide and methylcellulose. The mixture of the polyamide and the methyl cellulose may contribute to forming a stable concrete structure by providing fluidity, cohesion and material separation prevention, and incidentally, by preventing the contamination of the water by the excellent cohesive force and protecting the reinforcement of the concrete structure. It can work. It is preferable that the mixture of the polyamide and the methyl cellulose is contained in the re-emulsifying resin 0.01 to 5% by weight. When the mixture content of the polyamide and methyl cellulose exceeds 5% by weight, the viscosity of the composition for repairing the concrete structure may be increased, and workability may be lowered. When the mixture content of the polyamide and methyl cellulose is less than 0.1% by weight, the concrete structure The workability of the repair composition may be improved, but the effect of imparting fluidity, cohesive force, and material separation resistance may be weak. The mixture of polyamide and methyl cellulose is preferably a mixture of polyamide and methyl cellulose in a weight ratio of 0.1 to 0.8: 0.2 to 0.9 in order to provide a cohesive force and material separation prevention to form a stable concrete structure.

In addition, the re-emulsifying resin may further include an acrylamide emulsion. The acrylamide emulsion is used to lower the viscosity of the composition for repairing concrete structures to maintain workability as well as to improve water retention. In addition, the acrylamide emulsion is excellent in alkali resistance and has an effect of improving strength. The acrylamide emulsion is preferably contained in the re-emulsification resin 0.01 to 10% by weight. When the content of the acrylamide emulsion exceeds 10% by weight, the performance of the composition for repairing concrete structures may be improved, but the price may be lowered. If the content of the acrylamide emulsion is less than 0.01% by weight, the workability of the composition for repairing concrete structures may be improved, but the effect of improving alkali resistance and water retention may be weak.

In addition, the re-emulsification resin may further include an ethylene vinyl acetate resin. The ethylene vinyl acetate resin is used to improve the adhesion, durability and heat resistance of the composition for repairing concrete structures. The ethylene vinyl acetate resin is preferably contained 0.1 to 40% by weight in the re-emulsification resin, when the content of the ethylene vinyl acetate resin exceeds 40% by weight, the performance of the composition for repairing the concrete structure is improved, but the price competitiveness is lowered When the content of the ethylene vinyl acetate resin is less than 0.1% by weight, the workability of the composition for repairing concrete structures may be improved, but the effect of improving adhesion, durability, and heat resistance may be weak.

In addition, the re-emulsifying resin may further include a styrene-acrylic ester resin. The styrene-acrylic ester resin is used to enhance acid resistance and alkali resistance of the composition for repairing concrete structures. The styrene-acrylic ester resin is preferably contained in the re-emulsification resin 0.1 to 30% by weight. When the content of the styrene-acrylic ester resin exceeds 30% by weight, the performance of the composition for repairing the concrete structure is improved, but the price competitiveness This may fall, if the content of the styrene-acrylic ester resin is less than 0.1% by weight, the workability of the composition for repairing the concrete structure is improved, but the effect of enhancing acid resistance and alkali resistance may be weak.

In addition, the re-emulsifying resin may further include an antifoaming agent for removing the bubbles in the re-emulsifying resin to increase the strength and durability. The antifoaming agent is used to remove the bubbles in the reemulsification resin to increase the strength and durability. In addition, when the antifoaming agent is added to the re-emulsifying resin can impart an air entraining effect to improve workability and pot life. It is preferable that the said defoaming agent is contained 0.01 to 2 weight% in the said reemulsification type resin. Examples of the defoaming agent include alcohol defoaming agents, silicone defoaming agents, fatty acid defoaming agents, oil defoaming agents, ester defoaming agents and oxyalkylene defoaming agents. Examples of the silicone defoaming agent include dimethyl silicone oil, polyorganosiloxane, and fluorosilicone oil. Examples of the fatty acid defoaming agent include stearic acid and oleic acid. Examples of the oil-based antifoaming agents include kerosene, animal and plant oil, and castor oil. Examples of the ester type antifoaming agents include solitol trioleate, glycerol monoricinolate, and the like. Examples of the oxyalkylene antifoaming agents include polyoxyalkylene, acetylene ethers, polyoxyalkylene diisocyanate esters, and polyoxyalkylene alkylamines. Examples of the alcohol-based defoaming agent include glycol.

In addition, the re-emulsifying resin may further include a water reducing agent for improving the strength and durability by reducing the water-cement ratio. The water reducing agent is used to reduce the water-cement ratio to improve strength and durability, and to secure the fluidity of the reemulsified resin. When a water reducing agent is added to the reemulsifying resin, the water-cement ratio is reduced. It is preferable that the said water reducing agent is contained 0.01 to 2 weight% in reemulsification type resin. The water reducing agent may be a polycarboxylic acid-based, melamine-based or naphthalene-based water reducing agent, but naphthalene-based and melamine-based may reduce the strength of the composition and lower workability and pot life compared to the polycarboxylic acid-based strength, workability And a polycarboxylic acid-based water reducing agent that does not lower the pot life.

Hereinafter, a method for producing a composition for repairing a concrete structure according to a preferred embodiment of the present invention.

In the composition for repairing concrete structures according to a preferred embodiment of the present invention, 15 to 70% by weight of the cement composition, 25 to 70% by weight of the fine aggregate, and 0.01 to 15% by weight of the reemulsifying resin are premixed in a vacuum forced mixer. After that, 0.1 to 15% by weight of water may be added and mixed by a forced mixer or continuous mixer for a predetermined time (for example, 1 to 10 minutes).

Hereinafter, a method of repairing a concrete structure using the above-described composition for repairing a concrete structure is provided. Hereinafter, the concrete structure is referred to as a chemical plant, a food factory, a related structure such as a barn floor, an offshore concrete structure, an underwater concrete structure, a sewer pipe, a road surface of a road, a bridge bridge, a concrete slab of a bridge, a new expansion joint, etc. As a structure, it is used to mean a structure made of concrete.

The method for repairing a concrete structure according to a preferred embodiment of the present invention includes the steps of removing impurities, latencies, deteriorated parts, etc. of the concrete structure with a hand water jet, a high pressure water washer, and the like; And, by pouring the composition for repairing the concrete structure on the primer-treated upper portion to recover the cross-section, and the surface-finished result of the restored cross-section and applying a surface protective agent to the finishing treatment.

The deteriorated portion may be removed to a lower portion of the reinforcing bar, and the exposed reinforcing bar may be rustproofed before the primer treatment. When the hand water jet or high pressure water washing machine is used, the reinforcing bars of the concrete structure are not exposed in the normal case, but the reinforcing bars may be exposed in the deteriorated areas when the deterioration is severe. It is desirable to prevent corrosion.

Hereinafter, the primer treatment is used to mean applying a material that facilitates the concrete structure repair composition is attached to the concrete structure. The primer treatment may use at least one material selected from styrene-butadiene latex, polyacrylic ester, acryl, ethyl vinyl acetate, methyl methacrylate, and silane compound, but is not limited thereto.

The surface protecting agent may use at least one material selected from styrene-butadiene latex, polyacrylic ester, acryl, ethyl vinyl acetate, methyl methacrylate, and silane compound, but is not limited thereto.

Hereinafter, the embodiments of the composition for repairing concrete structures according to the present invention are described in more detail, and the present invention is not limited to the following examples.

≪ Example 1 >

45% by weight of cement composition, 45% by weight of aggregate and 6% by weight of reemulsifying resin were premixed in a vacuum forced mixer, and then 4% by weight of water was added and stirred with a forced mixer for 2 minutes to prepare a composition for repairing concrete structures. Prepared.

At this time, the cement composition is usually 35% by weight of Portland cement, 25% by weight of blast furnace slag, 10% by weight of fly ash, 5% by weight of silica fume, 5% by weight of gypsum anhydrous, 5% by weight of calcium sulfoaluminate, 5% by weight of alumina cement. 2% by weight of zinc oxide, 2% by weight of zeolite and 5% by weight of rice husk ash, 0.5% by weight of retardant and 0.5% by weight of reducing agent were used. Citric acid was used as the retardant. The water reducing agent used a polycarboxylic acid-based water reducing agent.

The fine aggregate was used by mixing 80% by weight silica siliceous, 10% by weight mica and 10% by weight vermiculite.

The re-emulsifying resin is 95% by weight of styrene-butadiene resin powder, 2% by weight of polyethersulfone resin powder, 1% by weight of polymethyl methacrylate resin, 1% by weight of sodium polyacrylate resin, 0.5% by weight of antifoaming agent, 0.5% by weight of reducing agent Was used by mixing. The antifoaming agent was a silicone antifoaming agent. The water reducing agent used a polycarboxylic acid-based water reducing agent.

<Example 2>

45% by weight of cement composition, 45% by weight of aggregate and 6% by weight of reemulsifying resin were premixed in a vacuum forced mixer, and then 4% by weight of water was added and stirred with a forced mixer for 2 minutes to prepare a composition for repairing concrete structures. Prepared.

At this time, the cement composition is usually 35% by weight of Portland cement, 25% by weight of blast furnace slag, 10% by weight of fly ash, 5% by weight of silica fume, 5% by weight of gypsum anhydrous, 5% by weight of calcium sulfoaluminate, 5% by weight of alumina cement. 2% by weight of zinc oxide, 2% by weight of zeolite and 5% by weight of rice husk ash, 0.5% by weight of retardant and 0.5% by weight of reducing agent were used. Citric acid was used as the retardant. The water reducing agent used a polycarboxylic acid-based water reducing agent.

The fine aggregate was used by mixing 80% by weight silica siliceous, 10% by weight mica and 10% by weight vermiculite.

The reemulsifying resin is 90% by weight of styrene-butadiene resin powder, 5% by weight polyethersulfone resin powder, 2% by weight polymethyl methacrylate resin, 2% by weight sodium polyacrylate resin, 0.5% by weight antifoaming agent, 0.5% by weight reducing agent Was used by mixing. The antifoaming agent was a silicone antifoaming agent. The water reducing agent used a polycarboxylic acid-based water reducing agent.

<Example 3>

45% by weight of cement composition, 45% by weight of aggregate and 6% by weight of reemulsifying resin were premixed in a vacuum forced mixer, and then 4% by weight of water was added and stirred with a forced mixer for 2 minutes to prepare a composition for repairing concrete structures. Prepared.

At this time, the cement composition is usually 35% by weight of Portland cement, 25% by weight of blast furnace slag, 10% by weight of fly ash, 5% by weight of silica fume, 5% by weight of gypsum anhydrous, 5% by weight of calcium sulfoaluminate, 5% by weight of alumina cement. 2% by weight of zinc oxide, 2% by weight of zeolite and 5% by weight of rice husk ash, 0.5% by weight of retardant and 0.5% by weight of reducing agent were used. Citric acid was used as the retardant. The water reducing agent used a polycarboxylic acid-based water reducing agent.

The fine aggregate was used by mixing 80% by weight silica siliceous, 10% by weight mica and 10% by weight vermiculite.

The reemulsifying resin is 80% by weight styrene-butadiene resin powder, 11% by weight polyethersulfone resin powder, 4% by weight polymethyl methacrylate resin, 4% by weight sodium polyacrylate resin, 0.5% by weight antifoaming agent, 0.5% by weight reducing agent Was used by mixing. The antifoaming agent was a silicone antifoaming agent. The water reducing agent used a polycarboxylic acid-based water reducing agent.

Comparative Examples which can be compared with the embodiments of the present invention are shown in order to more easily grasp the characteristics of Examples 1 to 3. Comparative Examples 1 and 2 to be described later are examples of the common cement A mortar composition and a polymer-cement mortar composition.

&Lt; Comparative Example 1 &

Usually 45% by weight cement, 45% by weight aggregate and 10% by weight water were stirred with a forced mixer to prepare a normal cement mortar composition.

Comparative Example 2

Usually 45% by weight of cement, 45% by weight of fine aggregate and 6% by weight of styrene-butadiene resin powder are premixed with a vacuum forced mixer, followed by stirring for 2 minutes with a forced mixer by adding 4% by weight of water to prepare a polymer cement mortar composition. Prepared.

The following test examples show the experimental results comparing the characteristics of the examples according to the invention with the characteristics of Comparative Examples 1 and 2 to more easily understand the characteristics of Examples 1 to 3 according to the present invention .

&Lt; Test Example 1 >

In order to compare the physical properties of the concrete structure repair composition prepared in Examples 1 to 3 and the cement mortar composition prepared in Comparative Examples, the concrete structure prepared according to Examples 1 to 3 described above The cement mortar composition prepared by the repair composition and Comparative Example 1 and Comparative Example 2 was subjected to a compressive strength test by KS F 2405 (mortar compressive strength test method), the results are shown in Table 1 below. Bending strength test was carried out by KS F 2408 (Bending strength test method of mortar), Tensile strength test was conducted by KS F 2423 (Tensile strength test method of mortar), JIS A 6916 (Tension adjustment material for finishing paint) And the results are shown in Table 1. The results are shown in Table 1. &lt; tb &gt; &lt; TABLE &gt;

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2
burglar
(kgf / cm2) warp 90 96 102 66 79 compression 488 502 529 439 448 Seal 52 58 68 30 42 adhesion 22 26 30 16 20

As shown in Table 1, the bending, compression, tensile and adhesive strength of the concrete structure repair composition prepared according to Examples 1 to 3 compared to the cement mortar composition prepared according to Comparative Examples 1 and 2 It was much higher.

It was confirmed that the composition for repairing the concrete structure prepared according to Examples 1 to 3 was much superior in strength compared to the cement mortar composition prepared in Comparative Examples.

&Lt; Test Example 2 &

The dry shrinkage rate of the concrete structure repairing composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2 were measured by KS F 2424 (Test method for changing the length of concrete). The results are shown in Table 2 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Dry Shrinkage (%) 0.10 0.07 0.04 0.18 0.12

As shown in Table 2, the repairing composition for the concrete structure prepared according to Examples 1 to 3 is reduced in the amount of dry shrinkage compared to the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2 to reduce the shrinkage effect It could be confirmed.

<Test Example 3>

Absorption rate according to the method specified in JIS A 1171 (test method for polymer cement mortar) of the concrete structure repair composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 and 2 The measurement results of are shown in Table 3 below. If the water absorption rate is high, impurities or water penetrate into the interior of the concrete, the porosity increases in the interior of the concrete, thereby causing a problem of causing damage to the structure.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Absorption rate (%) 0.8 0.65 0.53 2.9 1.2

As shown in Table 3 above, the composition for repairing concrete structures prepared according to Examples 1 to 3 had a lower absorption rate than the cement mortar compositions prepared according to Comparative Examples 1 and 2.

<Test Example 4>

The concrete structure repairing composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 and 2 were tested according to JIS A 1171 (test method of polymer cement mortar), The results are shown in Table 4 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Chloride ion penetration depth (mm) 1.0 0.8 0.65 2.0 1.3

As shown in Table 4 above, the concrete structure repairing composition prepared according to Examples 1 to 3 has less chloride ion penetration depth compared to the cement mortar compositions prepared according to Comparative Examples 1 and 2, resulting in less salt damage. It was confirmed that the resistance to high.

&Lt; Test Example 5 >

The concrete structure repairing composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 and 2 were tested according to JIS A 1171 (test method of polymer cement mortar), The results are shown in Table 5 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Neutralization Depth (mm) 0.6 0.3 0.2 1.6 0.9

As shown in Table 5, the composition for repairing concrete structures prepared according to Examples 1 to 3 has a smaller neutralization penetration depth than the cement mortar compositions prepared according to Comparative Examples 1 and 2. It was confirmed that the resistance is high.

&Lt; Test Example 6 >

Concrete composition repairing composition prepared according to Examples 1 to 3 and cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2 according to the Japanese Industrial Standards [Test method of chemical resistance by solution deposition of concrete] The measurement results of the chemical resistance test were immersed in a test solution for 28 days with an aqueous solution of 2% hydrochloric acid, 5% sulfuric acid, and 45% sodium hydroxide as a test solution.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Weight change rate
(%) Hydrochloric acid -1.9 -1.4 -1.1 -9.0 -2.5 Sulfuric acid -0.2 -0.2 0 -1.8 -0.8 Sodium hydroxide +0.5 +0.8 +1.1 -0.1 +0.2

As shown in Table 6 above, the composition for repairing concrete structures prepared according to Examples 1 to 3 showed less weight change rate for chemical resistance than the cement mortar compositions prepared according to Comparative Examples 1 and 2. It was confirmed that the resistance to chemical resistance was high.

&Lt; Test Example 7 >

Measurement results of the freeze-thaw resistance test according to the method specified in KS F 2456 for the concrete structure repairing composition prepared in Examples 1 to 3 and the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2 are shown below. It is shown in Table 7. Freezing and thawing means that the water absorbed in the capillary is frozen and melted in the concrete. If the freezing and thawing is repeated, fine cracks are generated in the concrete structure and the durability is lowered. Table 7 shows the durability indexes of the respective examples and comparative examples according to the freeze-thaw resistance test.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Durability index 90 91 92 65 88

As shown in Table 7, the composition for repairing the concrete structure prepared according to Examples 1 to 3 is significantly higher durability index than the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, durability It can be seen that the improvement.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, This is possible.

Claims (11)

15 to 70 wt% of cement composition, 25 to 70 wt% of fine aggregate, 0.01 to 15 wt% of reemulsifying resin and 0.1 to 15 wt% of water,
The re-emulsifying resin is 50 to 95% by weight of styrene-butadiene resin powder for improving strength and adhesion, 0.1 to 20% by weight of polyethersulfone resin powder for improving adhesion and heat resistance, for improving acid resistance and alkali resistance 0.1-20% by weight of polymethyl methacrylate resin and 0.1-20% by weight of sodium polyacrylate resin for improving strength and durability,
The fine aggregate is 50 to 95% by weight silica siliceous, 1 to 30% by weight mica and 1 to 20% by weight vermiculite composition for repairing a concrete structure.
The method of claim 1, wherein the cement composition,
Usually 15 to 70% by weight of Portland cement, 15 to 55% by weight of blast furnace slag, 5 to 30% by weight of fly ash, 1 to 20% by weight of silica fume, 1 to 20% by weight of gypsum anhydrous, 1 to 15% by weight of calcium sulfoaluminate , 0.1 to 10% by weight of alumina cement, 0.01 to 10% by weight of zinc oxide, 0.01 to 10% by weight of zeolite and 0.01 to 10% by weight of rice husk ash. .
The composition for repairing concrete structures according to claim 2, wherein the cement composition further comprises 0.01 to 10% by weight of titanium oxide.
delete According to claim 1, The re-emulsified resin is a mixture of polyamide and methyl cellulose in a weight ratio of 0.1 to 0.8: 0.2 to 0.9 ratio by weight 0.01 to 5 in order to provide a cohesive force and material separation prevention to form a stable concrete structure Concrete structure repair composition, characterized in that it further comprises a weight%.
The composition for repairing concrete structures according to claim 1, wherein the reemulsifying resin further comprises 0.01 to 10% by weight of acrylamide emulsion.
The composition for repairing concrete structures according to claim 1, wherein the reemulsification resin further comprises 0.1 to 40% by weight of ethylene vinyl acetate resin.
The composition for repairing concrete structures according to claim 1, wherein the reemulsifying resin further comprises 0.1 to 30% by weight of styrene-acrylic ester resin.
Removing impurities, latencies and deteriorated areas of the concrete structure with a hand water jet or high pressure water washer;
Primer treatment on the removed site;
Restoring the cross section by pouring the composition for repairing the concrete structure according to claim 1 on the primer-treated upper portion; And
Surface finishing the result of the restoration of the cross-section and the method of repairing the concrete structure, characterized in that it comprises the step of finishing by applying a surface protective agent.
The method of claim 9, wherein the primer treatment uses at least one material selected from styrene-butadiene latex, polyacrylic ester, acrylic, ethyl vinyl acetate, methyl methacrylate and silane-based compound,
The surface protector is a repair method for a concrete structure, characterized in that using at least one material selected from styrene-butadiene latex, poly acrylic ester, acrylic, ethyl vinyl acetate, methyl methacrylate and silane compounds.
10. The method of claim 9, wherein the deteriorated portion is removed to the bottom of the reinforcement, and the method of repairing a concrete structure further comprising the step of rust treatment of the exposed rebar before the step of the primer treatment.