KR101825152B1 - Cement mortar composition for repairing concrete structure with excellent corrosion-resistance and functionality and method for repairing section of concrete structure - Google Patents

Abstract

The present invention relates to a cement mortar composition for repairing a concrete composition and a concrete structure cross section repairing method using the same. The cement mortar composition includes: 3-45 wt% of functional binder; 5-80 wt% of fine aggregate; 0.1-30 wt% of performance modifier; and 0.1-30 wt% of water. The functional binder includes: 5-50 wt% of crude Portland cement; 5-40 wt% of alumina cement; 0.1-30 wt% of blast furnace slag find powder; 0.01-15 wt% of zinc oxide; 0.01-15 wt% of aluminum nitride; 0.01-10 wt% of bentonite; 0.01-10 wt% of zirconium; 0.01-10 wt% of chromate; 0.01-10 of retarder; and 0.01-10 wt% of defoamer. The present invention has effects of improving functionality, reinforcing a surface, and improving strength and durability by latent hydraulic activity and pozzolanic reaction. The present invention can improve adhesion, flexural toughness, salt resistance, neutralization resistance, and freezing and thawing resistance by using a performance modifier. The present invention can reduce open time by shortening a construction period by improving field construction and implementing early strength. The present invention can obtain an effect of remarkably reducing maintenance costs by preventing concrete corrosion caused by chemical erosion in places such as a sewage end treatment plant structure, a hydraulic structure, a water stop structure, a underground structure, a canal tunnel, a sewer pipe, a sewer culvert, and a precast product by having excellent strength and durability, especially corrosion resistance, anticorrosion, antifouling property, salt resistance, acid resistance, and water tightness.

Description

TECHNICAL FIELD [0001] The present invention relates to a cement mortar composition for repairing a concrete structure having excellent corrosion resistance and functionality, and to a concrete structure repair method using the same. [0002] The present invention relates to a cement mortar composition for repairing a concrete structure,

The present invention relates to a cement mortar composition for repairing a concrete structure and a method of repairing a concrete structure using the same. More particularly, the present invention relates to a cement mortar composition for repairing a concrete structure, Hardness, and functionality of a cement mortar composition, and can reduce the opening time by shortening the construction time because it can exhibit early strength. The present invention relates to a cement mortar composition for repairing a concrete structure and a method for repairing a section of a concrete structure using the same.

In general, cracks occur in concrete due to deterioration of the concrete structure. When the time passes, the compressive strength of the concrete and the tensile strength of the reinforcing bar gradually decrease, and the concrete exposed through the cracks is neutralized and corrosion of the reinforcing bars occurs . If these rebar corrosion phenomena become severe, the concrete structure may eventually collapse. Therefore, if the concrete structure deteriorates and cracks are generated, it is necessary to repair the deteriorated part quickly.

It is very probable that chemical corrosion problems occur in the general environment. It is very probable that the organic matter contained in the sewage can be reacted by the bacteria to generate sulfate ions, thereby eroding the concrete, or by the acidic material such as the spring zone or acid rain, And the concrete structure is corroded by the sulfite of the reinforced concrete structure related to the end-of-sewage treatment. Structures subject to chemical corrosion include structures related to stormwater and sewage-related structures, chemical plants, water purification facilities, drainage systems, agricultural waterways, watercraft, and water gates, soil pollution and water purification plants, underground structures of sewage treatment plants, sewage- .

On the other hand, when cracks occur in the concrete due to deterioration of the concrete structure, especially, the road central separation wall, the wing wall, the road side wall portion, the concrete slab of the bridge, the road surface, The tensile strength of the reinforcing bars is gradually decreased, and the concrete exposed through the cracks is subjected to chlorine ion penetration, freezing and thawing, and neutralization, resulting in corrosion of the reinforcing bars. If these rebar corrosion phenomena become severe, the concrete structure may eventually collapse. In repairing such a concrete structure, a maintenance material excellent in strength and durability as that of a concrete-polymer composite is used because it can not secure required quality only by cementitious materials.

Korean Patent No. 10-1523589 (May 28, 2015) Korean Registered Patent No. 10-1141347 (May 03, 2012)

The problem to be solved by the present invention is to provide a steel sheet which has flexural strength, tensile strength, adhesion strength, flexural toughness, acid resistance, flame retardancy, neutralization resistance, freeze-thaw resistance, surface hardness and functionality, The present invention provides a cement mortar composition for repairing a concrete structure capable of reducing a traffic opening time and a method for repairing a section of a concrete structure using the same.

The present invention relates to a vinyl chloride-vinyl acetate copolymer composition comprising from 3 to 45% by weight of a functional binder, from 5 to 80% by weight of a fine aggregate, from 0.1 to 30% by weight of a performance modifier, and from 0.1 to 30% 1 to 30% by weight of dimethylaminoethyl acrylate, 0.1 to 25% by weight of 2-ethylhexyl acrylate, methyl methacrylate-acrylonitrile-butadiene-styrene copolymer 0.1 To 25% by weight of an ethylene-methyl acrylate copolymer and 0.01 to 25% by weight of an ethylene-methyl acrylate copolymer.

The performance modifier may further include 0.01 to 10% by weight of hydroxybutyl polyester to improve weather resistance, heat resistance and water resistance.

The performance modifier may further include 0.01 to 10% by weight of a polyethylene glycol ester-polyethyleneimine copolymer for improving self-leveling properties.

Wherein the functional binder comprises 5 to 50% by weight of crude steel Portland cement, 5 to 40% by weight of alumina cement, 0.1 to 30% by weight of blast furnace slag, 0.01 to 15% by weight of zinc oxide, 0.01 to 15% 0.01 to 10% by weight of zirconium, 0.01 to 10% by weight of chromate, 0.01 to 10 of retarder and 0.01 to 10% by weight of defoamer.

The functional binder may further contain 0.01 to 10% by weight of a high-performance water reducing agent to ensure a water-cement ratio lowering and workability.

The functional binder may further include 0.01 to 10% by weight of an inorganic pigment to express color.

The functional binder may further include 0.001 to 10% by weight of hydrophilic fibers to prevent bending strength, tensile strength and plastic cracking. As the hydrophilic fiber, any one or one or more of nylon fiber, PP fiber, PE fiber and PVA fiber may be mixed and used.

The fine aggregate may comprise 30 to 99% by weight of silica silica, 0.1 to 40% by weight of sericite, 0.1 to 35% by weight of cinnabar and 0.1 to 35% by weight of vermiculite.

The present invention also provides a method of manufacturing a concrete structure, comprising: chipping away and deteriorating a deteriorated portion, run-in, and impurities of a concrete structure by a planer, a short blaster, or a hand water jet; Applying a penetration type surface strengthening agent for improving adhesion, surface hardening and durability of the cement mortar composition for repair, and a device for spraying the cement mortar composition for repairing the concrete structure to the upper surface to which the penetration type surface strengthening agent is applied And then finishing the surface with a styrofoam, a trowel or the like before curing; And curing by surface finishing; And applying a surface protecting agent to prevent penetration of harmful substances such as water, chlorine ions, and carbon dioxide after curing and to improve freeze-thaw resistance and weather resistance, and a method of repairing a surface of a concrete structure . At this time, if the reinforcing bars are exposed in the step of chipping, removing, and cleaning, rust may be removed, followed by rust-proofing by applying a rust inhibitor.

The penetration type surface strengthening agent may include at least one material selected from styrene-butadiene, ethylene-vinyl acetate, polyacrylic ester, acrylic emulsion, aqueous silica-based penetration enhancer and silicate-based penetration-type surface enhancer. At this time, as the surface protecting agent, at least one substance selected from an aqueous silica sol, a solventless epoxy resin, a urethane-acrylic polymer, and a silane-based compound may be used.

According to the cement mortar composition for repairing a concrete structure of the present invention, functional binders and fine aggregates are used to improve functionalities, surface hardenability, strength and durability by potential hydraulic and pozzolanic reactions. Further, by using the performance modifier, it is possible to improve the adhesiveness, the flexural toughness, the salt resistance, the neutralization resistance and the freeze-thaw resistance. Also, by using the performance modifier, the field workability of the cement mortar composition for repairing a concrete structure can be improved, early strength can be developed, and the construction period can be shortened and the opening time can be shortened. In addition, it has excellent strength and durability, especially corrosion resistance, antifouling property, antifouling property, salt resistance, acid resistance and watertightness, and can be used for chemical treatment such as sewage terminal treatment plant structure, hydraulic structure, exponential structure, underground structure, canal tunnel, sewer pipe, It is possible to prevent corrosion of concrete caused by erosion, and the maintenance cost to be used can be remarkably reduced.

Further, according to the present invention, since it has excellent compressive strength, bending strength and adhesion strength, it can be easily applied not only to a sewage facility having a large amount of acidic substances, a concrete index structure in contact with water but also to various existing methods, It is possible to mechanize construction such as construction and the like, so that it has many effects such as improvement of work efficiency and 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.

The cement mortar composition for repairing concrete structures according to a preferred embodiment of the present invention comprises 3 to 45% by weight of a functional binder, 5 to 80% by weight of a fine aggregate, 0.1 to 30% by weight of a performance modifier, and 0.1 to 30% by weight of water.

The performance modifier is used to improve workability, bending strength, tensile strength, corrosion resistance, durability, flexural toughness, flame retardancy, neutralization resistance, freeze-thaw resistance and abrasion resistance. Wherein the performance modifier is selected from the group consisting of 25-98 wt% vinyl acetate-vinyl chloride copolymer, 1-30 wt% dimethylaminoethyl acrylate, 0.1-25 wt% 2-ethylhexyl acrylate, methyl methacrylate- acrylonitrile- -Styrene copolymer and 0.01 to 25% by weight of an ethylene-methyl acrylate copolymer.

The performance modifier is preferably contained in an amount of 0.1 to 30% by weight based on the cement mortar composition for repairing concrete structures. If the content of the performance modifier is more than 30% by weight, the viscosity is lowered and the material separation is likely to occur and the price competitiveness may be lowered. If the content of the performance modifier is less than 0.1 wt%, the effect of improving the flow performance, strength, corrosion resistance, durability, toughness, flame retardancy, neutralization resistance, freeze / thaw resistance and wear resistance may be small.

The vinyl acetate-vinyl chloride copolymer is used to induce bonding between inorganic materials and to improve strength and durability. The content of the vinyl acetate-vinyl chloride copolymer is preferably 25 to 98% by weight based on the performance modifier. When the content of the vinyl acetate-vinyl chloride copolymer is less than 25% by weight, And if it is more than 98% by weight, it is difficult to expect the effect of inducing further inter-inorganic-inorganic bond and improving the strength and durability, and it is not economical.

The dimethylaminoethyl acrylate serves to improve adhesion and toughness. The dimethylaminoethyl acrylate is preferably contained in an amount of 1 to 30% by weight based on the performance modifier. When the content of the dimethylaminoethyl acrylate is less than 1% by weight, the effect of improving adhesion and toughness may be insignificant. When the content of the dimethylaminoethyl acrylate exceeds 30% by weight, it is difficult to expect further adherence and toughness improving effect and it is not economical.

The 2-ethylhexyl acrylate is used for improving the strength and durability of the cement mortar composition for repairing concrete structures. The 2-ethylhexyl acrylate is preferably contained in an amount of 0.1 to 25% by weight based on the performance modifier. When the content of the 2-ethylhexyl acrylate exceeds 25% by weight, the performance of the cement mortar composition for repairing concrete structures But the workability and price competitiveness may be deteriorated. If the content of 2-ethylhexyl acrylate is less than 0.1% by weight, the workability of the cement mortar composition for repairing concrete structures is improved, but the effect of improving strength and durability is weak .

The methyl methacrylate-acrylonitrile-butadiene-styrene copolymer is used for obtaining workability and strength improving effect. The methyl methacrylate-acrylonitrile-butadiene-styrene copolymer is preferably contained in an amount of 0.1 to 25% by weight based on the performance modifier, and the content of the methyl methacrylate-acrylonitrile-butadiene- When the content of the methyl methacrylate-acrylonitrile-butadiene-styrene copolymer is less than 0.1% by weight, the workability and the strength improvement effect Can be lowered.

The ethylene-methyl acrylate copolymer is used to improve the durability of the cement mortar composition for repairing concrete structures. The ethylene-methyl acrylate copolymer is preferably contained in an amount of 0.01 to 25% by weight based on the performance modifier. If the content of the ethylene-methyl acrylate copolymer exceeds 25% by weight, workability and price competitiveness may be deteriorated. When the content of the ethylene-methyl acrylate copolymer is less than 0.01% by weight, the durability improving effect is weak and the bonding strength of the performance modifier may be lowered.

The performance modifier may further include a hydroxybutyl polyester to improve weather resistance, heat resistance and water resistance. The content of the hydroxybutyl polyester is preferably 0.01 to 10% by weight with respect to the performance modifier. If the content of the hydroxybutyl polyester exceeds 10% by weight, the strength and water resistance may be improved but the price competitiveness may be deteriorated. If the content of the hydroxybutyl polyester is less than 0.01% by weight, the workability is improved but the effect of improving the strength and water resistance may be weak.

In addition, the performance modifier may further include a polyethylene glycol ester-polyethyleneimine copolymer for improving self-leveling property. The polyethylene glycol ester-polyethyleneimine copolymer is preferably contained in an amount of 0.01 to 10% by weight based on the performance modifier. When the content of the polyethylene glycol ester-polyethyleneimine is more than 10% by weight, the reaction between the organic materials is delayed, And when the content of the polyethylene glycol ester-polyethyleneimine copolymer is less than 0.01% by weight, there is no material separation phenomenon, but the effect of improving the self-leveling property may be weak.

The functional binder is used to develop initial strength, to improve durability, to suppress temperature rise, to improve corrosion resistance, to improve functionality and abrasion resistance, and the cement mortar composition for repairing the concrete structure By weight based on 100% by weight of the functional binder. If the content of the functional binder exceeds 45% by weight, the strength and durability are improved, but cracks tend to occur due to the expansion and contraction effect. When the content is less than 3% Workability and cracking are reduced, but the effect of improving strength and durability may be weak.

Wherein the functional binder comprises 5 to 50% by weight of crude steel Portland cement, 5 to 40% by weight of alumina cement, 0.1 to 30% by weight of blast furnace slag, 0.01 to 15% by weight of zinc oxide, 0.01 to 15% 0.01 to 10% by weight of zirconium, 0.01 to 10% by weight of chromate, 0.01 to 10 of retarder and 0.01 to 10% by weight of defoamer.

The crude steel portland cement is preferably used as specified in KS, and cement distributed in the market can be used. The crude steel portland cement is preferably contained in the functional binder in an amount of 5 to 50% by weight.

The alumina cement is an inorganic fastidious mineral material that is added to increase hydration reactivity and to suppress cracking. It reacts with water in an instant when it comes into contact with water to form an ettringite hydrate, and when mixed with cement And an excellent compressive strength can be obtained within a short time. The alumina cement is preferably contained in an amount of 5 to 40% by weight based on the functional binder. When the content of the alumina cement is less than 5% by weight, the strength improvement effect and the crack generation inhibiting effect may be insignificant. When the content of the alumina cement exceeds 40% by weight It is possible to obtain good physical properties due to fast curing characteristics, but it is not economical because the manufacturing cost is high.

The blast furnace slag fine powder is used as a latent hydraulic material to improve long-term strength and durability. The fine blast furnace slag powder is preferably contained in an amount of 0.1 to 30% by weight based on the functional binder. If the content of the blast furnace slag powder exceeds 30% by weight, the initial strength development is deteriorated. If the blast furnace slag powder content is less than 0.1% by weight, the effect of improving long-term strength and improving durability may be weak.

The zinc oxide is used to improve strength, ultraviolet resistance and material separation resistance. The zinc oxide is preferably contained in an amount of 0.01 to 15% by weight based on the weight of the functional binder. When the content of zinc oxide is less than 0.01% by weight, the effect of improving the strength, ultraviolet ray and material separation resistance may be insignificant. When the content of zinc oxide is less than 0.01% by weight, When the content exceeds 15% by weight, the performance is improved but the strength is lowered and the price is less competitive.

The aluminum nitride can be used to improve heat resistance and corrosion resistance. The aluminum nitride is preferably contained in an amount of 0.01 to 15% by weight based on the functional binder. If the content of the aluminum nitride is less than 0.01% by weight, the effect of improving heat resistance and corrosion resistance may be insignificant. If the content of the aluminum nitride exceeds 15% by weight The workability is lowered and the manufacturing cost is increased, which is not economical.

The bentonite is used as a hygroscopic agent to prevent material separation and control viscosity. The bentonite is preferably contained in the functional binder in an amount of 0.01 to 10% by weight. If the content of bentonite is less than 0.01 wt%, the workability is good but the effect of preventing material separation may be small. If the content of bentonite is more than 10 wt%, the material separation phenomenon does not occur but the viscosity is increased, have.

The zirconium is used for improving strength, fire resistance and corrosion resistance. When the weight ratio of zirconium is increased, long-term strength development, fire resistance and corrosion resistance are improved. The zirconium is preferably contained in an amount of 0.01 to 10% by weight based on the functional binder. If the content of zirconium exceeds 10 wt%, the performance improves but the price competitiveness decreases. If the content of zirconium is less than 0.01 wt%, the effect of improving long-term strength, improving fire resistance and corrosion resistance may be weak.

The chromate salt is used to improve the rust prevention effect. The chromium salt is preferably contained in an amount of 0.01 to 10 wt% based on the functional binder. When the content of the chromium salt is less than 0.01% by weight, the rust inhibitive effect may be insufficient. When the content of the chromium salt exceeds 10% by weight, the performance is improved. A decrease in strength may occur.

The retarder is used for delaying rapid curing in order to ensure workability for a predetermined period of time, and is preferably contained in an amount of 0.01 to 10% by weight based on the functional binder. 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.

Further, the antifoaming agent is used for removing bubbles to increase strength and durability. The antifoaming agent is preferably contained in an amount of 0.01 to 10% by weight based on the functional binder. 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.

The functional binder may further include a high-performance water reducing agent to secure a water-cement ratio lowering and workability. The high performance water reducing agent may further include 0.01 to 10% by weight based on the functional binder. As the high performance water reducing agent, it is preferable to use a polycarboxylic acid type high performance water reducing agent.

The functional binder may further include an inorganic pigment for realizing hue and improving the appearance. The inorganic pigment may be contained in an amount of 0.01 to 10% by weight based on the functional binder. The inorganic pigment is added so as to be easily distinguished, the color can be easily identified with a clearer color, and the color persistence can be improved. The inorganic pigment may be at least one selected from the group consisting of red iron oxide, yellow iron oxide, chromium oxide (CrO ₃ ), purple iron oxide and black iron oxide (carbon black) Blue, and white.

The functional binder may further include hydrophilic fibers to prevent flexural strength, tensile strength, and plastic cracks. The hydrophilic fiber is preferably contained in an amount of 0.001 to 10% by weight based on the functional binder. As the hydrophilic fiber, any one or one or more of nylon fiber, PP fiber, PE fiber and PVA fiber may be mixed and used.

The fine aggregate preferably comprises 30 to 99% by weight of silica silica, 0.1 to 40% by weight of sericite, 0.1 to 35% by weight of cinnabar and 0.1 to 35% 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 particle size of 5 mm or less in comparison with coarse aggregate. It has the advantage of excellent heat insulation and strength and excellent durability against acidity, salt and so on by using fine sandstone, phyllite, and vermiculite mixed with fine pots, self-repairing function, deodorizing, antibacterial, waterproof and far infrared effect.

The silica silica is used to improve strength and abrasion resistance. It is preferable to use silica silica having a particle diameter of 0.5 to 2.0 mm. The silica silica is preferably contained in an amount of 30 to 99% by weight based on the fine aggregate.

The sericite has antimicrobial, deodorizing and waterproofing functions and is used to enhance the bioactivity effect by releasing far infrared ray. It is preferable that the grain size of the sericite is 2 mm or less. If the grain size of the sericite is larger than this, there is a fear that the fluidity of the cement mortar composition may be lowered, and if it is smaller than that, the workability of the cement mortar composition may be lowered. It is preferable that the sericite is contained in an amount of 0.1 to 40% by weight based on the fine aggregate.

The phyllotaxis has pozzolanic characteristics and is used to obtain long-term strength development and durability improvement effects as well as index and self-healing effects. The cinder mortar is preferably contained in an amount of 0.1 to 35% by weight based on the fine aggregate.

The vermiculite is a clay mineral composed of a silicate of hydroxide and has a fine porous structure and is excellent in the ability to absorb and has excellent heat insulation and is used to prevent condensation. The vermiculite is preferably contained in an amount of 0.1 to 35% by weight based on the fine aggregate.

The cement mortar composition for repairing concrete structures according to a preferred embodiment of the present invention is prepared by mixing 3 to 45% by weight of a functional binder, 5 to 80% by weight of a fine aggregate and 0.1 to 30% by weight of a performance modifier in a forced or vacuum mixer for a predetermined time 1 to 5 minutes) and 0.1 to 30% by weight of water are further added thereto, followed by mixing with a forced mixer or a continuous mixer for a predetermined time (for example, 1 to 5 minutes).

The present invention proposes a method for repairing a section of a concrete structure using a cement mortar composition for repairing the concrete structure.

Hereinafter, the concrete structure refers to structures such as an underground structure, an exponential structure, an offshore structure, a road central separating wall, a wing wall, a road surface, a road surface, a bridge bridge, a concrete slab of a bridge, As used in the present invention.

According to a preferred embodiment of the present invention, there is provided a method for repairing a section of a concrete structure, comprising: chipping away and deteriorating a deteriorated part, a run-in part and an impurity of a concrete structure with a planer, a short blaster, or a hand water jet; Applying a penetration type surface strengthening agent for improving the adhesion, surface strengthening and durability of the concrete concrete and the cement mortar composition for repairing the concrete structure; and applying a penetration type surface strengthening agent to the concrete structure repair agent For example, by spraying a cement mortar composition, and then finishing the surface by using a styrofoam or a trowel before curing; And curing by surface finishing; And applying a surface protecting agent to prevent penetration of harmful substances such as water, chlorine ions, and carbon dioxide after curing and to improve freeze-thaw resistance and weather resistance, and a method of repairing a surface of a concrete structure .

In this case, the cleaning step may further include a step of using the vacuum suction vehicle as a cleaner when cleaning the area where the repair area is large.

 At this time, if the reinforcing bars are exposed in the step of chipping, removing, and cleaning, rust may be removed, followed by rust-proofing by applying a rust inhibitor.

The penetration type surface strengthening agent may include at least one material selected from styrene-butadiene, ethylene-vinyl acetate, polyacrylic ester, acrylic emulsion, aqueous silica-based penetration enhancer and silicate-based penetration-type surface enhancer.

As the surface protecting agent, at least one substance selected from an aqueous silica sol, a solventless epoxy resin, a urethane-acrylic polymer, and a silane-based compound may be used.

Hereinafter, embodiments of the cement mortar composition for repairing concrete structures according to the present invention will be more specifically shown, and the present invention is not limited by the following embodiments.

≪ Example 1 >

42 wt% of the functional binder, 48 wt% of the fine aggregate, and 4 wt% of the performance modifier were premixed in a forced mixer, and 6 wt% of water was added thereto, followed by stirring in a forced mixer for 2 minutes to prepare a cement mortar composition for repairing concrete structures . At this time, fine aggregates were used in which 80% by weight of silica silica, 10% by weight of sericite, 5% by weight of cinnabar and 5% by weight of vermiculite were mixed.

The performance modifier was prepared by mixing 89 wt% vinyl acetate-vinyl chloride copolymer, 3 wt% dimethylaminoethyl acrylate, 2 wt% 2-ethylhexyl acrylate, 2 wt% methylmethacrylate-acrylonitrile-butadiene- , 2% by weight of an ethylene-methyl acrylate copolymer, 1% by weight of a hydroxybutyl polyester and 1% by weight of a polyethylene glycol ester-polyethyleneimine copolymer.

Wherein the functional binder is selected from the group consisting of 41 wt% crude steel portland cement, 20 wt% alumina cement, 15 wt% blast furnace slag, 5 wt% zinc oxide, 5 wt% aluminum nitride, 5 wt% bentonite, 5 wt% zirconium, 0.5% by weight of a retarder, 0.5% by weight of a defoamer, 0.5% by weight of a high-performance water reducing agent, 1% by weight of an inorganic pigment and 0.5% by weight of a hydrophilic fiber. The defoamer was a silicone defoamer. The high performance water reducing agent used was a polycarboxylic acid based high performance water reducing agent. Gray pigments were used as the inorganic pigments. The hydrophilic fiber used was nylon fiber.

≪ Example 2 >

42 wt% of the functional binder, 48 wt% of the fine aggregate, and 4 wt% of the performance modifier were premixed in a forced mixer, and 6 wt% of water was added thereto, followed by stirring in a forced mixer for 2 minutes to prepare a cement mortar composition for repairing concrete structures . At this time, fine aggregates were used in which 80% by weight of silica silica, 10% by weight of sericite, 5% by weight of cinnabar and 5% by weight of vermiculite were mixed.

The performance modifier was prepared by mixing 83 wt% vinyl acetate-vinyl chloride copolymer, 4 wt% dimethylaminoethyl acrylate, 3 wt% 2-ethylhexyl acrylate, 3 wt% methylmethacrylate- acrylonitrile-butadiene- , 3% by weight of an ethylene-methyl acrylate copolymer, 2% by weight of a hydroxybutyl polyester and 2% by weight of a polyethylene glycol ester-polyethyleneimine copolymer.

Wherein the functional binder is selected from the group consisting of 41 wt% crude steel portland cement, 20 wt% alumina cement, 15 wt% blast furnace slag, 5 wt% zinc oxide, 5 wt% aluminum nitride, 5 wt% bentonite, 5 wt% zirconium, 0.5% by weight of a retarder, 0.5% by weight of a defoamer, 0.5% by weight of a high-performance water reducing agent, 1% by weight of an inorganic pigment and 0.5% by weight of a hydrophilic fiber. The defoamer was a silicone defoamer. The high performance water reducing agent used was a polycarboxylic acid based high performance water reducing agent. Gray pigments were used as the inorganic pigments. The hydrophilic fiber used was nylon fiber.

≪ Example 3 >

42 wt% of the functional binder, 48 wt% of the fine aggregate, and 4 wt% of the performance modifier were premixed in a forced mixer, and 6 wt% of water was added thereto, followed by stirring in a forced mixer for 2 minutes to prepare a cement mortar composition for repairing concrete structures . At this time, fine aggregates were used in which 80% by weight of silica silica, 10% by weight of sericite, 5% by weight of cinnabar and 5% by weight of vermiculite were mixed.

The performance modifier was a mixture of 77% by weight of a vinyl acetate-vinyl chloride copolymer, 5% by weight of dimethylaminoethyl acrylate, 4% by weight of 2-ethylhexyl acrylate, 4% by weight of methyl methacrylate-acrylonitrile-butadiene- , 4% by weight of an ethylene-methyl acrylate copolymer, 3% by weight of a hydroxybutyl polyester and 3% by weight of a polyethylene glycol ester-polyethyleneimine copolymer.

Wherein the functional binder is selected from the group consisting of 41 wt% crude steel portland cement, 20 wt% alumina cement, 15 wt% blast furnace slag, 5 wt% zinc oxide, 5 wt% aluminum nitride, 5 wt% bentonite, 5 wt% zirconium, 0.5% by weight of a retarder, 0.5% by weight of a defoamer, 0.5% by weight of a high-performance water reducing agent, 1% by weight of an inorganic pigment and 0.5% by weight of a hydrophilic fiber. The defoamer was a silicone defoamer. The high performance water reducing agent used was a polycarboxylic acid based high performance water reducing agent. Gray pigments were used as the inorganic pigments. The hydrophilic fiber used was nylon fiber.

A comparative example which can be compared with the embodiments of the present invention is shown in order to more easily grasp the characteristics of the above-described first to third embodiments. It is to be noted that Comparative Example 1 described below is provided merely for comparison with the characteristics of the embodiments, and is not a prior art of the present invention.

≪ Comparative Example 1 &

42% by weight of crude steel Portland cement, 48% by weight fine aggregate and 4% by weight of vinyl acetate-vinyl chloride copolymer were premixed in a forced mixer, and 6% by weight of water was added and stirred in a forced mixer for 2 minutes to prepare a composition . At this time, silica fine silica was used as the fine aggregate.

The following test examples show experimental results comparing characteristics of the embodiment of the present invention and the characteristics of the first comparative example so that the characteristics of the first to third embodiments of the present invention can be grasped more easily.

≪ Test Example 1 >

Flow test (degree of kneading) was carried out according to the method defined in KS F 2476 for the cement mortar composition for repairing concrete structures and the composition prepared according to Comparative Example 1 prepared according to Examples 1 to 3. The flow test is to test the dough of the composition such as the flue and viscosity of the composition. The larger the value, the better the workability, that is, the workability at the time of pouring the composition.

Table 1 below shows the changes in the flow over time.

division Example 1 Example 2 Example 3 Comparative Example 1 Flow (mm) 21 22 23 18

As shown in Table 1 above, it can be seen that the cement mortar composition for repairing concrete structures manufactured according to Examples 1 to 3 is superior in workability to the composition prepared according to Comparative Example 1.

≪ Test Example 2 &

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were subjected to flexural, compressive and compressive stresses according to the method specified in KS F 4042 (polymer cement mortar for repairing concrete structures) Bond strength test was carried out. The results are shown in Table 2 below.

Example 1 Example 2 Example 3 Comparative Example 1 burglar
(N / mm ² ) warp 11.1 12.1 12.6 9.8 compression 54.1 55.8 58.5 52.2 adhesion Standard condition 2.3 2.4 2.48 2.1 After warm-cold repeat 2.2 2.25 2.31 2.0

As shown in Table 2 above, the cement mortar composition for repairing concrete structures produced according to Examples 1 to 3 had significantly higher strength than the composition prepared according to Comparative Example 1.

≪ Test Example 3 >

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were measured by KS F 4042 (polymer cement mortar for repairing concrete structures) Are shown in Table 3 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Length change rate (%) 0.03 0.02 0.015 0.048

As shown in Table 3, it can be seen that the cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 has a shrinkage reduction effect by decreasing the rate of change in length as compared with the composition prepared according to Comparative Example 1 there was.

<Test Example 4>

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were measured according to the method specified in KS F 4042 (polymer cement mortar for repairing concrete structures) The results are shown in Table 4.

division Example 1 Example 2 Example 3 Comparative Example 1 Permeability (g) 4.3 3.2 2.5 6.9

As shown in Table 4 above, the cement mortar composition for repairing concrete structures according to Examples 1 to 3 was less water-permeable than the composition prepared according to Comparative Example 1, showing excellent water resistance.

&Lt; Test Example 5 >

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were tested with KS F 4042 (polymer cement mortar for repairing concrete structures) The results are shown in Table 5 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Neutralization depth (mm) 1.1 0.8 0.5 1..7

As shown in Table 5 above, the cement mortar composition for repairing concrete structures according to Examples 1 to 3 had a lower neutralization penetration depth than the composition prepared according to Comparative Example 1, and showed high resistance to neutralization I could confirm.

&Lt; Test Example 6 >

The chloride ion penetration resistance test of the concrete structure repairing cement mortar composition prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 was performed with KS F 4042 (polymer cement mortar for repairing concrete structures) , And the results are shown in Table 6.

division Example 1 Example 2 Example 3 Comparative Example 1 Chloride ion penetration resistance (coulombs) 670 617 550 885

As shown in Table 6 above, the cement mortar composition for repairing concrete structures according to Examples 1 to 3 exhibited less resistance to chloride ion penetration than the composition prepared according to Comparative Example 1, Respectively.

&Lt; Test Example 7 >

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were immersed in a saturated calcium hydroxide solution (50 mm 2) by KS F 4042 (polymer cement mortar for repairing concrete structures) ) &Lt; / RTI &gt; for 28 days and then cooled to room temperature to measure compressive strength. The results of the alkali resistance test are shown in Table 7 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Compressive strength
(N / mm ² ) 50.1 52.3 54.6 47.8

As shown in Table 7, the cement mortar composition for repairing concrete structures according to Examples 1 to 3 had a higher compressive strength than the composition prepared according to Comparative Example 1, showing a high resistance to alkalinity I could confirm.

<Test Example 8>

The moisture permeation resistance test of the concrete structure repairing cement mortar composition prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 was carried out with KS F 4042 (polymer cement mortar for repairing concrete structures) The results are shown in Table 8 below.

Example 1 Example 2 Example 3 Comparative Example 1 Moisture permeation resistance (m) 0.5 0.4 0.3 0.8

As shown in Table 8 above, it was found that the cement mortar composition for repairing concrete structures manufactured according to Examples 1 to 3 had better moisture permeation resistance than the composition prepared according to Comparative Example 1. [

&Lt; Test Example 9 >

The water absorption coefficient test of the concrete structure repairing cement mortar composition prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 was performed by KS F 4042 (polymer cement mortar for repairing concrete structures) The results are shown in Table 9 below.

Example 1 Example 2 Example 3 Comparative Example 1 Water absorption coefficient ^{(kg / m 2 ?? h 0} .5) 0.18 0.16 0.14 0.25

As shown in Table 9, it was found that the water absorption coefficient of the cement mortar composition for repairing concrete structures according to Examples 1 to 3 was lower than that of the composition prepared according to Comparative Example 1. [

&Lt; Test Example 10 &

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were subjected to a freeze-thaw resistance test according to the method defined in KS F 2456. Freezing and thawing means that the water absorbed in the concrete is frozen and melted. When freezing and thawing is repeated, fine cracks are generated in the concrete structure and the durability is lowered.

Table 10 shows the durability indexes of the respective examples and the comparative example 1 according to the freeze-thaw resistance test.

division Example 1 Example 2 Example 3 Comparative Example 1 Durability index 92 92 93 88

As shown in Table 10, the durability of the cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 was much higher than that of the composition prepared according to Comparative Example 1, have.

&Lt; Test Example 11 &

The cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1 were subjected to chemical resistance test according to the Japanese Industrial Standards (original test method for chemical resistance test by solution immersion in concrete) The aqueous solution of 5% sulfuric acid and 45% sodium hydroxide was immersed in the test solution for 28 days. The results of the chemical resistance test are shown in Table 11 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Weight change rate
(%) Hydrochloric acid -0.9 -0.78 -0.59 -1.1 Sulfuric acid 0 0 0.1 -0.2 Sodium hydroxide +0.7 +1.1 +1.3 +0.3

As shown in Table 11, the cement mortar composition for repairing concrete structures manufactured according to Examples 1 to 3 exhibited less weight change rate with respect to chemical resistance than the composition prepared according to Comparative Example 1, And the resistance was high.

&Lt; Test Example 12 >

In order to compare the properties of the cement mortar composition for repairing concrete structures prepared according to Examples 1 to 3 and the composition prepared according to Comparative Example 1, a rust prevention rate test was conducted using KS F 2561 (rust inhibitor for reinforced concrete) And the results are shown in Table 12 below.

Test Items Example 1 Example 2 Example 3 Comparative Example 1 Rust prevention rate (%) 95.3 96.8 97.3 92.1

As shown in Table 12, it was confirmed that the cement mortar composition for repairing concrete structures according to Examples 1 to 3 had a higher anti-rusting effect than the composition prepared according to Comparative Example 1, .

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 (9)

delete delete A cement mortar composition for repairing concrete structures,
3 to 45 wt% of a functional binder, 5 to 80 wt% of a fine aggregate, 0.1 to 30 wt% of a performance modifier, and 0.1 to 30 wt% of water,
The performance modifier may comprise 25 to 98% by weight of a vinyl acetate-vinyl chloride copolymer, 1 to 30% by weight of dimethylaminoethyl acrylate, 0.1 to 25% by weight of 2-ethylhexyl acrylate, 0.1 to 25% by weight of acrylonitrile-butadiene-styrene copolymer, 0.01 to 25% by weight of ethylene-methyl acrylate copolymer, 0.01 to 10% by weight of hydroxybutyl polyester, and 0.1 to 10% by weight of polyethylene glycol ester- 0.01 to 10% by weight
Wherein the cement mortar composition is a cement mortar composition for repairing concrete structures.
The method of claim 3,
Wherein the functional binder comprises 5 to 50% by weight of crude steel Portland cement, 5 to 40% by weight of alumina cement, 0.1 to 30% by weight of blast furnace slag, 0.01 to 15% by weight of zinc oxide, 0.01 to 15% by weight of aluminum nitride, 0.01 to 10% by weight of zirconium, 0.01 to 10% by weight of zirconium, 0.01 to 10% by weight of zirconium, 0.01 to 10% of retardant, and 0.01 to 10% by weight of defoamer.
5. The method of claim 4,
Wherein the functional binder further comprises 0.01 to 10% by weight of a high-performance water reducing agent to reduce the water-cement ratio and workability.
6. The method of claim 5,
Wherein the functional binder further comprises 0.01 to 10% by weight of an inorganic pigment in order to express color.
The method according to claim 6,
The functional binder preferably further comprises 0.001 to 10% by weight of hydrophilic fibers to prevent bending strength, tensile strength and plastic cracking. The hydrophilic fibers may be any one or more of nylon fiber, PP fiber, PE fiber, The cement mortar composition for repairing concrete structures according to claim 1,
The method of claim 3,
Wherein the fine aggregate comprises 30 to 99% by weight of silica silica, 0.1 to 40% by weight of sericite, 0.1 to 35% by weight of cinnabar and 0.1 to 35% by weight of vermiculite.
9. A method of repairing a concrete structure using a cement mortar composition for repairing a concrete structure according to any one of claims 3 to 8,
Removing and cleaning deterioration sites, runtans or impurities of the concrete structure;
Applying a penetration type surface strengthening agent to the cleaned site to improve the adhesion, surface hardening and durability of the concrete concrete and the cement mortar composition for repairing the concrete structure;
Placing the cement mortar composition for repairing the concrete structure on the top of the permeable surface strengthening agent;
Curing and curing the surface of the concrete structure repair cement mortar composition; And
Applying a surface protecting agent to prevent penetration of harmful substances such as water, chlorine ions, and carbon dioxide after curing and to improve freeze-thaw resistance and weather resistance;
Wherein the reinforcing member is formed of a reinforcing material.