KR101352903B1 - Cement mortar composite with excellent flowability and workability, repair method of concrete structure, injection repair method for the concrete structure, surface treating method of the concrete structure and surface protection method of the concrete structure using the composite - Google Patents

Abstract

The present invention relates to a cement mortar composition, which comprises 15-55 weight% of cement-base binding agent, 15-55 weight% of fine aggregate, 0.1-30 weight% of admixture and 5-40 weight% of water, wherein the admixture comprises 75-99 weight% of styrene-butadiene resin, 0.1-10 weight% of polymethacrylate-butylacrylate resin, 0.1-10 weight% of polyvinylacetate ethylene resin, 0.1-10 weight% of polystyrene-butylacrylate resin and 0.01-5 weight% of methacrylamide, and a repair method of a concrete structure, an injection repair method to a concrete structure, a surface treatment method of a concrete structure and a surface protection method of a concrete structure using the same. According to the present invention, the construction is facilitated as the fluidity is excellent; the construction period, the construction cost and the repair period are reduced due to the rapid hardening; and the service period of a concrete structure is increased, the maintenance cost is reduced and the constructability is enhanced as the field applicability, the workability, the bridge surface waterproof layer protection, the resistance against chloride penetration, the durability, the adherence and the water proof property are excellent.

Description

Cement mortar composite with excellent flowability and workability, Cement mortar composite with excellent flowability and workability, repair method for concrete structure, injection repair method for concrete structure, surface treatment method for concrete structure and surface protection treatment method for concrete structure method of concrete structure, injection repair method for the concrete structure, surface treating method of the concrete structure and surface protection method of the concrete structure using the composite}

The present invention relates to a cement mortar composition having excellent fluidity and workability, repair method of concrete structure, injection repair method for concrete structure, surface treatment method of concrete structure and surface protection treatment method of concrete structure. Its excellent fluidity makes it easy to install, and it cures in a short time, which shortens the construction period, reduces construction costs, and shortens the maintenance period. On-site applicability, workability, resistance to chloride penetration, protection of bridge waterproof layer, durability, and adhesion. Cement mortar composition that can realize the increase of common period of concrete structure, reduction of maintenance cost and improvement of construction property, waterproofing method of concrete structure, injection repair method of concrete structure, surface treatment method of concrete structure Surface beam of concrete structure It relates to a treatment method.

Concrete structures, especially concrete slabs of bridges, road surfaces, under bridges, sewer pipes, underground structures, exponential structures, and so on, cause cracks in concrete, which leads to a decrease in the compressive strength and tensile strength of the concrete. In addition, concrete exposed through cracks is neutralized and corrosion of rebar occurs. If the corrosion of the reinforcing bar becomes more severe, the concrete structure may eventually collapse. Therefore, when the concrete structure is deteriorated and cracks occur, it is necessary to repair the deteriorated portion as soon as possible.

Polymer cement mortar is widely used in repair work to repair and reinforce the sites where such corrosion or erosion occurs a lot.

Polymer cement mortar mixed with SBR (styrene butadiene rubber) latex is widely used as the construction method for the reconstruction of concrete structures, but mortar mixed with SBR latex is finished after mortar casting due to the material properties of latex with high viscosity. This difficult and thicker polymer coating film causes problems such as initial plastic cracking and long-term cracking.

The problem to be solved by the present invention is excellent fluidity, easy to install, hardening within a short time to shorten the construction period, it is possible to reduce the construction cost and maintenance period, field applicability, workability, protection of the cross-section waterproof layer, Cement mortar composition, concrete repair method, injection repair method for concrete structure, which can realize the increase of common period of concrete structure, reduction of maintenance cost and improvement of construction by excellent chloride penetration resistance, durability, adhesion and waterproofness, The present invention provides a surface treatment method for a concrete structure and a surface protection treatment method for a concrete structure.

The present invention comprises 15 to 55% by weight cement-based binder, 15 to 55% by weight fine aggregate, 0.1 to 30% by weight admixture and 5 to 40% by weight of water, wherein the admixture is 75 to 99% by weight styrene-butadiene resin, poly 0.1-10 wt% of methyl methacrylate-butyl acrylate resin, 0.1-10 wt% of polyvinylacetate ethylene resin, 0.1-10 wt% of polystyrene-butyl acrylate resin and 0.01-5 wt% of methacrylamide A cement mortar composition is provided.

The admixture may further comprise 0.001 to 3% by weight of at least one material selected from polyethylene oxide, urethane and polycarboxylic acid to improve self leveling.

In addition, the admixture may further comprise 0.001 to 5% by weight of at least one material selected from polyvinyl methyl ether, polyvinyl alcohol and polyvinylamine to prevent material separation.

In addition, the admixture may further comprise 0.001 to 5% by weight of polycarbonate resin in order to improve the water resistance and wear resistance.

The cement-based binder is 20 to 90% by weight of crude steel cement, 5 to 50% by weight of magnesium sulfoaluminate, 0.1 to 20% by weight of alumina cement, 0.1 to 20% by weight of calcium aluminate, 0.1 to 20% by weight of blast furnace slag, 0.1% glass bubble 20 wt%, gypsum 0.1-10 wt% and aluminum powder 0.01-5 wt%.

The cement-based binder may further comprise 0.001 to 5% by weight of at least one material selected from polycarboxylic acid, naphthalene, melamine and lignin.

In addition, the cement-based binder may further comprise 0.001 to 6% by weight of at least one material selected from methyl cellulose, starch and gum.

In addition, the cement-based binder may further comprise 0.01 to 3% by weight of nylon fibers.

In addition, the cement-based binder has a ratio (L / D) of length (L) to diameter (D) in the range of 20 to 150 and contains 0.01 to 3% by weight of macrofiber composed of at least one material selected from polyethylene and polypropylene. It may further include.

In addition, the present firing, the chipping and removing the impurities or deterioration of the concrete slab, the step of cleaning the chipped site, improves the adhesion of the concrete slab and the cement mortar composition, water penetration and chlorine ion penetration It provides a repair method for the concrete structure, comprising the step of applying a primer for inhibiting and improving the water resistance and water resistance, and laying the cement mortar composition.

In addition, the present invention, the step of cutting the cracks generated in the concrete structure by using a concrete cutter V-cut or U-cut, cleaning the impurities or slurry of the cut portion, and the cement mortar in the cut portion It provides an injection repair method for a concrete structure comprising the step of curing by injecting the composition.

In addition, the present invention, the step of chipping the site where the surface peeling by the scaling, the aggregate dropout, the microcracks caused by plastic cracking on the concrete structure, the step of cleaning the impurities or slurry of the chipped site, chipped It provides a surface treatment method of a concrete structure comprising the step of applying a primer to the site, and the step of curing by laying the cement mortar composition on the primer is applied.

In addition, the present invention, the step of removing the latans or impurities on the surface of the concrete structure, the step of applying a primer to the site from which the latans or impurities are removed, the primer is applied to increase the commonness of the concrete structure It provides a surface protection treatment method of the concrete structure, comprising the step of curing by laying the cement mortar composition on top.

According to the cement mortar composition of the present invention, it is excellent in field applicability, workability, chloride penetration resistance, bridge waterproofing layer protection, durability, adhesiveness and waterproofness to increase the common period of concrete structures, reduce maintenance costs and improve construction properties have.

In addition, the cement mortar composition of the present invention is excellent in fluidity, easy to install, and cured in a short time to shorten the construction period, it is possible to reduce the construction cost and shorten the maintenance period.

According to the concrete structure repair method, the injection repair method for the concrete structure, the surface treatment method of the concrete structure using the cement mortar composition of the present invention, the cement mortar composition excellent in fluidity and workability is fast diameter and exhibits high strength and durability, Not only can shorten the construction period, increase the service life of the concrete structure, but also reduce the cost of maintenance, and it has excellent strength characteristics and durability to increase the cost of public service and maintenance. Can be saved.

According to the injection repair method for the concrete structure using the cement mortar composition of the present invention, the cement mortar composition excellent in fluidity and workability is fast diameter and exhibits high strength and durability, thereby shortening the construction period and reducing the service life of the concrete structure. Not only can it increase, but it can reduce the cost of maintenance, and it can reduce the cost of increasing the period of use and maintenance by having the excellent strength characteristics and durability.

According to the surface treatment method of the concrete structure using the cement mortar composition of the present invention, the cement mortar composition having excellent fluidity and workability is fast diameter and exhibits high strength and durability, thereby shortening the construction period and increasing the service life of the concrete structure. Not only can it reduce the cost of maintenance, but it also has excellent strength characteristics and durability, which reduces the cost of increasing the period of use and maintenance.

According to the surface protection treatment method of the concrete structure using the cement mortar composition of the present invention, the cement mortar composition excellent in fluidity and workability is fast diameter and exhibits high strength and durability, thereby shortening the construction period and reducing the service life of the concrete structure. Not only can it increase, but it can reduce the cost of maintenance, and it can reduce the cost of increasing the period of use and maintenance by having the excellent strength characteristics and durability.

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.

Hereinafter, the concrete structure includes not only ordinary roads and expressways but also all the structures made of concrete including a bridge for vehicles, a concrete slab for bridges, a road surface, a bridge bottom, a sewer pipe, an underground structure, It is used as meaning.

Cement mortar composition excellent in fluidity and workability according to a preferred embodiment of the present invention includes a cement-based binder, fine aggregates, admixtures and water. The cement mortar composition preferably contains 15 to 55% by weight cement-based binder, 15 to 55% by weight fine aggregate, 0.1 to 30% by weight admixture and 5 to 40% by weight of water.

The fine aggregate is preferably contained 15 to 55% by weight in the cement mortar composition. Aggregate is divided into fine aggregate and coarse aggregate, hereinafter the particle diameter is less than 5mm is called fine aggregate. As the fine aggregate, it is preferable to use a mixture of No. 6 silica sand and No. 7 silica sand in a weight ratio of 0.05 to 0.4: 0.6: 0.95.

The cement-based binder is preferably contained 15 to 55% by weight in the cement mortar composition. The cement binder includes crude steel cement, magnesium sulfoaluminate, alumina cement, calcium aluminate, blast furnace slag, glass bubble, gypsum and aluminum powder. The cement-based binder is 20 to 90% by weight of crude steel cement, 5 to 50% by weight of magnesium sulfoaluminate, 0.1 to 20% by weight of alumina cement, 0.1 to 20% by weight of calcium aluminate, 0.1 to 20% by weight of blast furnace slag, 0.1% glass bubble It is preferable to contain -20 weight%, gypsum 0.1-10 weight%, and aluminum powder 0.01-5 weight%.

As for the crude steel cement, it is preferable to use the one specified in KS, and it is possible to use crude steel cement distributed on the market. The crude steel cement is preferably contained 20 to 90% by weight in the cement-based binder.

The magnesium sulfoaluminate is an inorganic cemented carbide material, which reacts with water to produce ettringite hydrate in an instant when it comes into contact with water, thereby forming a general portland cement obtained in days or days when mixed with cement. The compressive strength can be obtained in a few hours. The magnesium sulfo aluminate is preferably contained 5 to 50% by weight in the cement binder. When the content of the magnesium sulfo aluminate is less than 5% by weight, it is difficult to expect sufficient initial strength, and when it exceeds 50% by weight, the strength is excellent, but workability and economic efficiency may be reduced.

The alumina cement is an inorganic-based ultra-rapid-speed cement material, and when mixed with cement, the compressive strength of ordinary portland cement obtained in several days or several days can be obtained within a few hours. The alumina cement preferably contains 0.1 to 20% by weight of the cement-based binder. If the content of the alumina cement is less than 0.1% by weight, initial strength development and durability performance may be weak. If the content is more than 20% by weight, workability and price competitiveness may be deteriorated.

The calcium aluminate is mixed with gypsum to react with water to produce ethrinzite, which is expanded when mixed with cement, and is used to prevent dry shrinkage. The calcium aluminate preferably contains 0.1 to 20% by weight of the cement binder. When the content of calcium aluminate is less than 0.1% by weight, it is difficult to expect sufficient initial strength expression and shrinkage reduction effect, and when it exceeds 20% by weight, the shrinkage effect is excellent but workability may be reduced.

The blast furnace slag serves to increase the long-term strength of the cement hardened body with the latent hard mineral fine powder and to increase the chemical resistance and durability by densifying the hydrated structure of the cement hardened body. The blast furnace slag is preferably contained 0.1 to 20% by weight in the cement-based binder. When the content of the blast furnace slag is less than 0.1% by weight, the effect of improving long-term strength and durability is weak, and when it exceeds 20% by weight, the initial strength may be delayed.

The glass bubble is a hollow glass material, and may be manufactured by blowing air into a central hole using a single cavity orifice nozzle or the like. The glass bubble is used to reduce the specific gravity of the composition to reduce the rebound amount of the material and improve the cosmetic properties. The glass bubble is preferably contained in the cement-based binder 0.1 to 20% by weight. When the content of the glass bubble is less than 0.1% by weight, the rebound amount and the effect of improving the plasticity may be weak, and when the content of the glass bubble exceeds 20% by weight, initial strength may be delayed and workability may be reduced.

The gypsum is used for initial strength development. The gypsum may be an anhydrous gypsum or an alumite. When the content of the gypsum is increased, rapid curing characteristics are exhibited. The gypsum is preferably contained in 0.1 to 10% by weight of the cement-based binder. If the gypsum content is less than 0.1% by weight, the initial strength expression effect may be weak, and when the content of the gypsum exceeds 10% by weight, workability and water resistance may be reduced.

The aluminum powder serves to suppress shrinkage by cement. The aluminum powder is preferably contained in the cement-based binder 0.01 to 5% by weight. When the content of the aluminum powder is less than 0.01% by weight, the effect of suppressing shrinkage due to cement may be weak, and when the content of the aluminum powder exceeds 5% by weight, workability may decrease.

The cement-based binder may further include nylon fibers. The nylon fiber is used to prevent flexural strength, tensile strength, and initial plastic cracking of the composition. The nylon fiber preferably has a ratio (L / D) of length (L) to diameter (D) in the range of 20 to 150. The nylon fiber is preferably contained in the cement-based binder 0.01 to 3% by weight. When the content of the nylon fiber is less than 0.01% by weight, the strength expression effect and the effect of preventing plastic cracking may be weak. When the content of the nylon fiber exceeds 3% by weight, workability and water resistance may be reduced.

In addition, the cement-based binder may further include a macro fiber. The macro fiber is used to prevent bending strength, tensile strength, and initial plastic cracking of the composition. Preferably, the macro fiber has a ratio (L / D) of length (L) to diameter (D) in the range of 20 to 150, for example, the macro fiber may have a diameter of 0.001 to 1.0 mm. have. The macro fiber is preferably made of at least one material selected from polyethylene and polypropylene. The macro fiber is preferably contained in the cement-based binder 0.01 to 3% by weight. When the content of the macrofibers is less than 0.01% by weight, the strength-expressing effect and the effect of preventing plastic cracking may be weak, and when the content of the macrofibers exceeds 3% by weight, workability and water resistance may be reduced.

The cement-based binder may further include at least one material selected from polycarboxylic acid, naphthalene, melamine, and lignin. The at least one material selected from polycarboxylic acid, naphthalene, melamine and lignin densifies the internal structure of the hardened cement body to improve water tightness and freeze-thawing resistance and enhance durability. It also facilitates penetration into voids by adding both viscous and fluidic properties to unsettled cement mortar. At least one material selected from polycarboxylic acid, naphthalene, melamine, and lignin is preferably contained in the cement binder in an amount of 0.001 to 5% by weight.

The cement-based binder may further include one or more materials selected from methyl cellulose, starch and gum. At least one material selected from methylcellulose, starch and gum is used to prevent material separation and workability of the cement mortar composition, and it is preferably contained in the cement binder in an amount of 0.001 to 6% by weight. Do.

The cement-based binder may further include a water reducing agent. The water reducing agent may be used to improve the strength and durability by reducing the water-cement ratio of the cement mortar composition. Examples of the water reducing agent include polycarboxylic acid, melamine, and naphthalene-based resins. Melamine-based or naphthalene-based water reducing agents are less effective in improving strength and durability than polycarboxylic acid water reducing agents, and have no significant effect of reducing water-cement ratio. The disadvantage is that the miscibility with the admixture is poor. Therefore, it is preferable to use a polycarboxylic acid-based water reducing agent in the cement mortar composition of the present invention. The water reducing agent is preferably contained in 0.01 to 5% by weight in the cement binder.

The cement-based binder may further include a retardant. The retarder is used to retard rapid curing to secure workability for a certain time, and preferably contains 0.001 to 4% by weight of the cement-based binder. As the retarder, generally well-known substances can be used, for example, sugars such as glucose, glucose, textine, dextran, gluconic acid, malic acid, citric acid, citric acid or salts thereof, aminocarboxylic acids or Salts thereof, phosphonic acid or derivatives thereof, polyhydric alcohols such as glycerin, and the like.

The admixture may be dispersed in the cement mortar cured body to form a film inside the cement mortar cured body to improve warpage, tensile and adhesion strength, and to improve water retention, thereby improving durability such as neutralization, chloride ion penetration, freeze-thawing, and the like. It serves to have flatness (self-leveling), it is preferably contained in 0.1 to 30% by weight in the cement mortar composition.

The admixture includes styrene-butadiene resin, polymethylmethacrylate-butylacrylate resin, polyvinylacetate ethylene resin, polystyrene-butylacrylate resin and methacrylamide. The admixture includes 75 to 99% by weight of styrene-butadiene resin, 0.1 to 10% by weight of polymethyl methacrylate-butylacrylate resin, 0.1 to 10% by weight of polyvinylacetate ethylene resin and 0.1 to 10% by weight of polystyrene-butylacrylate resin. It is preferable to contain% and 0.01-5 weight% of methacrylamide.

The styrene-butadiene resin forms a polymer film inside the cement mortar composition to enhance warpage, tensile and adhesion strength as well as improve durability due to the polymer film film. The styrene-butadiene resin is preferably contained in the admixture 75 to 99% by weight. When the content of the styrene-butadiene resin is less than 75% by weight, the strength and durability improvement effect may be insignificant. When the content of the styrene-butadiene is more than 99% by weight, the improvement effect may be obvious but the economic efficiency may be lowered.

The polymethyl methacrylate-butyl acrylate resin is used to improve ductility and dispersibility. The polymethyl methacrylate-butyl acrylate resin is preferably contained in 0.1 to 10% by weight of the admixture. When the content of the polymethyl methacrylate-butyl acrylate resin is less than 0.1% by weight, the ductility and dispersibility improvement effect may be insignificant. When it exceeds 10% by weight, the ductility is improved, but the material separation phenomenon easily occurs.

The polyvinylacetate ethylene resin is excellent in adhesive strength after curing, and serves to prevent desorption after adhesion by increasing the strength of cement. The polyvinylacetate ethylene resin is preferably contained in the admixture 0.1 to 10% by weight. When the content of the polyvinyl acetate ethylene resin is less than 0.1% by weight, the effect of improving the adhesive strength may be insignificant, and when the content of the polyvinyl acetate ethylene exceeds 10% by weight, the workability may be lowered due to a high viscosity.

The polystyrene-butylacrylate resin is used to improve the strength and durability of the cement mortar composition. The polypolystyrene-butylacrylate resin is preferably contained in 0.1 to 10% by weight of the admixture. When the content of the polystyrene-butyl acrylate resin is less than 0.1% by weight, the effect of improving strength and durability is inadequate, and when the content of the polystyrene-butylacrylate is more than 10% by weight, the viscosity is low, so that a material separation phenomenon easily occurs.

The methacrylamide is used to improve surface hardness and water resistance. It is preferable that the said methacrylamide is contained 0.01 to 5 weight% in the said admixture. When the content of the methacrylamide is less than 0.1% by weight, the effect of improving the surface hardness and water resistance is insufficient, and when the content of the methacrylamide is more than 5% by weight, the workability may decrease due to the increase in the viscosity.

The admixture may further include at least one material selected from polyethylene oxide, urethane, and polycarboxylic acid to improve self leveling, and the at least one material selected from polyethylene oxide, urethane, and polycarboxylic acid may be 0.001 in the admixture. It is preferable to contain-3 weight%.

In addition, the admixture may further comprise 0.001 to 5% by weight of at least one material selected from polyvinyl methyl ether, polyvinyl alcohol and polyvinylamine to prevent material separation.

In addition, the admixture may further comprise 0.001 to 5% by weight of polycarbonate resin in order to improve the water resistance and wear resistance.

In addition, the admixture may further comprise an antifoaming agent, the antifoaming agent is preferably contained in the admixture 0.01 to 5% by weight, the antifoaming agent is selected from polyether-based, silicone-based, ethyl alcohol-based and ethylene glycol-based It may be composed of the above materials.

Cement mortar composition according to a preferred embodiment of the present invention can be prepared by mixing admixtures, cement-based binders, fine aggregates and water, wherein the cement-based binder is contained 15 to 55% by weight in the cement mortar composition, the fine aggregates 15 to 55% by weight of the cement mortar composition, the admixture is contained 0.1 to 30% by weight in the cement mortar composition, the water is preferably contained in 5 to 40% by weight in the cement mortar composition.

Repairing method of a concrete structure using a cement mortar composition according to a preferred embodiment of the present invention, the step of chipping to remove impurities or deterioration of the concrete slab, the step of cleaning the chipped site, the concrete slab and cement mortar composition It includes the step of applying a primer for improving the adhesion of the water, inhibit the penetration of water and chlorine ions, and improve the water resistance and water resistance, and the step of laying the cement mortar composition after curing.

The impurities or deteriorated parts may be removed by chipping with a planarizer, shot blast, water jet, or the like, or may be removed by using an air jet using compressed air and then removed using a vacuum inhaler.

Hereinafter, the primer is used to mean a material to be applied (or coated) to facilitate the cement mortar composition, for example, the primer is styrene butadiene rubber latex, polyacrylic ester, ethyl vinyl acetate, methyl meta At least one material selected from acrylate and silane compounds may be used, but is not limited thereto.

Injection repair method for a concrete structure using a cement mortar composition according to a preferred embodiment of the present invention, the step of cutting the cracks generated in the concrete structure by using a concrete cutter V-cut or U-cut, Cleaning impurities and slurry with a hand water jet, a vacuum cleaner, and the like; and injecting and curing the cement mortar composition in the cut portion.

Surface treatment method of a concrete structure using a cement mortar composition according to a preferred embodiment of the present invention, the surface of the surface of the concrete structure due to scaling, dropping aggregates, fine cracking caused by plastic cracking planer, shot blaster Chipping, etc., cleaning impurities, slurry, etc. of the chipped portion with a hand water jet, a vacuum cleaner, etc., applying a primer to the chipped portion, and applying the cement mortar composition to the top of the primer. The step of curing and curing.

Surface protection treatment method of a concrete structure using a cement mortar composition according to a preferred embodiment of the present invention, the step of removing the latans or impurities on the surface layer of the concrete structure, and applying a primer to the site where the latans or impurities are removed And laying the cement mortar composition on the top to which the primer is applied to increase the commonness of the concrete structure.

Hereinafter, examples of the cement mortar composition excellent in fluidity and workability according to the present invention are described in more detail, and the present invention is not limited to the following examples.

≪ Example 1 >

A cement mortar composition was prepared by adding 40 wt% cement-based binder and 40 wt% fine aggregate to a forced mixer and stirring, further mixing 5 wt% admixture and 15 wt% water.

At this time, the cement-based binder, 40% by weight of crude steel cement, 20% by weight of magnesium sulfo aluminate, 15% by weight of alumina cement, 6% by weight of calcium aluminate, 6% by weight of blast furnace slag, 6% by weight of glass bubble, 5% by weight of gypsum. , 0.5 wt% aluminum powder, 0.5 wt% retardant, 0.5 wt% polycarboxylic acid and 0.5 wt% starch were used in combination. Citric acid was used as the retardant.

The admixture is 95% by weight of styrene-butadiene resin, 1% by weight of polymethyl methacrylate-butylacrylate resin, 1% by weight of polyvinylacetate ethylene resin, 1% by weight of polystyrene-butylacrylate resin, 1% by weight of methacrylamide , 0.5% by weight of the silicone-based antifoaming agent and 0.5% by weight of polyethylene oxide for improving self-leveling was used.

<Example 2>

A cement mortar composition was prepared by adding 40 wt% cement-based binder and 40 wt% fine aggregate to a forced mixer and stirring, further mixing 5 wt% admixture and 15 wt% water.

At this time, the cement-based binder, 40% by weight of crude steel cement, 20% by weight of magnesium sulfo aluminate, 15% by weight of alumina cement, 6% by weight of calcium aluminate, 6% by weight of blast furnace slag, 6% by weight of glass bubble, 5% by weight of gypsum. , 0.5 wt% aluminum powder, 0.5 wt% retardant, 0.5 wt% polycarboxylic acid and 0.5 wt% starch were used in combination. Citric acid was used as the retardant.

The admixture is 90% by weight of styrene-butadiene resin, 3% by weight of polymethyl methacrylate-butylacrylate resin, 2% by weight of polyvinylacetate ethylene resin, 2% by weight of polystyrene-butylacrylate resin, 2% by weight of methacrylamide , 0.5% by weight of the silicone-based antifoaming agent and 0.5% by weight of polyethylene oxide for improving self-leveling was used.

<Example 3>

A cement mortar composition was prepared by adding 40 wt% cement-based binder and 40 wt% fine aggregate to a forced mixer and stirring, further mixing 5 wt% admixture and 15 wt% water.

At this time, the cement-based binder, 40% by weight of crude steel cement, 20% by weight of magnesium sulfo aluminate, 15% by weight of alumina cement, 6% by weight of calcium aluminate, 6% by weight of blast furnace slag, 6% by weight of glass bubble, 5% by weight of gypsum. , 0.5 wt% aluminum powder, 0.5 wt% retardant, 0.5 wt% polycarboxylic acid and 0.5 wt% starch were used in combination. Citric acid was used as the retardant.

The admixture is 85% by weight of styrene-butadiene resin, 5% by weight of polymethyl methacrylate-butylacrylate resin, 3% by weight of polyvinylacetate ethylene resin, 3% by weight of polystyrene-butylacrylate resin, 3% by weight of methacrylamide , 0.5% by weight of the silicone-based antifoaming agent and 0.5% by weight of polyethylene oxide for improving self-leveling was used.

Comparative Example 1 and Comparative Example 2 are shown for comparison with the physical properties of the cement mortar composition prepared according to Examples 1 to 3 above.

&Lt; Comparative Example 1 &

Usually 40% by weight of Portland cement and 40% by weight of fine aggregate were added to a forced mixer and stirred, 19% by weight of water was further mixed, and then stirred for 2 minutes, and 1% by weight of polycarboxylic acid was added to prepare a cement mortar composition. .

Comparative Example 2

40% by weight cemented carbide and 40% by weight of fine aggregate were added to a forced mixer and stirred, and 5% by weight of styrene-butadiene resin and 15% by weight of water were further mixed, followed by stirring for 2 minutes to prepare a polymer cement mortar composition.

&Lt; Test Example 1 > Preparation of test specimens

A cement mortar composition was prepared by KS F 2476 (a method of making polymer cement mortar in a laboratory) according to the formulations presented in Examples 1 to 3 and Comparative Examples 1 to 2, and a cement mortar composition having dimensions of 4 x 4 x 16 The specimens were fabricated using 4 × 4 × 1 cm (for bonding strength test) molds for compression and bending strength tests, for drying shrinkage test, for chloride ion penetration depth test and for water absorption test, Curing was carried out to prepare specimens.

Test Example 2 Strength Test

In order to compare the physical properties of the cement mortar composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 to 2, each specimen prepared in Test Example 1 was subjected to KS F 2477 (Test method for strength of polymer cement mortar) and KS F 4916 (cement admixture polymer) were tested for compressive strength, flexural strength and adhesive strength, and the results are shown in Table 1 below.

division Strength (kgf / ㎠) compression warp adhesion 4 hours 1 day 7 days 4 hours 1 day 7 days 4 hours 1 day 7 days Example 1 205 308 378 60 81 105 18 24 27 Example 2 219 319 385 65 87 115 21 27 29 Example 3 225 327 392 69 94 122 22 28 31 Comparative Example 1 - 200 229 - 31 52 - 11 15 Comparative Example 2 195 299 342 55 72 95 15 19 22

As shown in Table 1, it can be seen that the cement mortar composition prepared according to Examples 1 to 3 has excellent initial compressive strength expression compared to the cement mortar compositions prepared according to Comparative Examples 1 and 2. It can be seen that traffic can be opened within several hours after pouring in a place where traffic is congested, and the cement mortar composition prepared according to Examples 1 to 3 is a case of using a admixture in Comparative Examples 1 and 2 Compared with the cement mortar composition prepared according to the present invention, it was found that the bending strength and the adhesive strength were very excellent.

Test Example 3 Drying Shrinkage Rate Measurement

After preparing the specimen as in Test Example 1, the dry shrinkage was measured by KS F 2424 (test method for changing the length of mortar and concrete), and the results are shown in Table 2 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Length change (%) 0.03 0.02 0.02 0.13 0.07

As shown in Table 2, the cement mortar composition prepared according to Examples 1 to 3 was found to have a very low dry shrinkage compared to the cement mortar compositions prepared according to Comparative Examples 1 and 2. It can be seen that the cement mortar composition prepared according to Examples 1 to 3 is more resistant to shrinkage after shrinkage than the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, .

<Test Example 4> Slump-flow measurement

The workability of the cement mortar composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 to 2 is shown in Table 3 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Slump flow (cm) 268 275 288 205 238

As shown in Table 3, the cement mortar composition prepared according to Examples 1 to 3 has a slump-flow value without bleeding and material separation in comparison with the cement mortar compositions prepared according to Comparative Examples 1 and 2. Was high. It was confirmed that the cement mortar composition prepared according to Examples 1 to 3 had excellent flowability and workability.

&Lt; Test Example 5 > Chloride ion penetration depth

In order to compare chloride ion penetration depths of the cement mortar composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 to 2, , A test was conducted by JIS A 6203 (polymer dispersion for cement admixture and re-oil type powder resin), and the results are shown in Table 4 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Chloride ion penetration depth (mm) 0.3 0.2 0.1 3.0 0.8

As shown in Table 4, the cement mortar composition prepared according to Examples 1 to 3 had a lower chloride ion penetration depth than the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, And the resistance was high.

&Lt; Test Example 6 >

In order to compare the absorption rates of the cement mortar composition prepared according to Examples 1 to 3 with the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, each of the specimens prepared in Test Example 1 was subjected to KS F 4916 (polymer for cement admixture), and the results are shown in Table 5 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Absorption Rate (%) 0.5 0.4 0.3 2.5 0.8

As shown in Table 5, the cement mortar composition prepared according to Examples 1 to 3 of the present invention showed a very low absorption rate as compared with the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2. This is due to the influence of the admixture was low water penetration was found to exhibit excellent performance in water resistance.

&Lt; Test Example 7 >

The cement mortar composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Examples 1 and 2 were subjected to a neutralization depth test according to JIS A 1171 (Test Method for Polymer Cement Mortar) The results are shown in Table 6.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Neutralization Depth (mm) 0.3 0.2 0.2 1.5 0.7

As shown in Table 6 above, the cement mortar composition prepared according to Examples 1 to 3 has a lower neutralization depth than the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, and thus has a high resistance to neutralization .

<Test Example 8>

The cement mortar composition prepared according to Examples 1 to 3 and the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2 were subjected to a freeze-thaw resistance test according to the method specified 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 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 93 94 94 55 90

As shown in Table 7, the durability index of the cement mortar composition prepared according to Examples 1 to 3 is much higher than that of the cement mortar composition prepared according to Comparative Example 1 and Comparative Example 2, Able to know.

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 (13)

15 to 55 weight percent cement-based binder, 15 to 55 weight percent of fine aggregate, 0.1 to 30 weight percent of admixture, and 5 to 40 weight percent of water,
The admixture includes 75 to 99% by weight of styrene-butadiene resin, 0.1 to 10% by weight of polymethyl methacrylate-butylacrylate resin, 0.1 to 10% by weight of polyvinylacetate ethylene resin and 0.1 to 10% by weight of polystyrene-butylacrylate resin. % And 0.01-5% by weight of methacrylamide,
The cement-based binder is 20 to 90% by weight of crude steel cement, 5 to 50% by weight of magnesium sulfoaluminate, 0.1 to 20% by weight of alumina cement, 0.1 to 20% by weight of calcium aluminate, 0.1 to 20% by weight of blast furnace slag, 0.1% glass bubble A cement mortar composition comprising -20 wt%, gypsum 0.1-10 wt%, and aluminum powder 0.01-5 wt%.
15 to 55 weight percent cement-based binder, 15 to 55 weight percent of fine aggregate, 0.1 to 30 weight percent of admixture, and 5 to 40 weight percent of water,
The admixture includes 75 to 99% by weight of styrene-butadiene resin, 0.1 to 10% by weight of polymethyl methacrylate-butylacrylate resin, 0.1 to 10% by weight of polyvinylacetate ethylene resin and 0.1 to 10% by weight of polystyrene-butylacrylate resin. % And 0.01-5% by weight of methacrylamide,
The admixture is a cement mortar composition, characterized in that it further comprises 0.001 to 3% by weight of at least one material selected from polyethylene oxide, urethane and polycarboxylic acid to improve self leveling.
15 to 55 weight percent cement-based binder, 15 to 55 weight percent of fine aggregate, 0.1 to 30 weight percent of admixture, and 5 to 40 weight percent of water,
The admixture includes 75 to 99% by weight of styrene-butadiene resin, 0.1 to 10% by weight of polymethyl methacrylate-butylacrylate resin, 0.1 to 10% by weight of polyvinylacetate ethylene resin and 0.1 to 10% by weight of polystyrene-butylacrylate resin. % And 0.01-5% by weight of methacrylamide,
The admixture is a cement mortar composition characterized in that it further comprises 0.001 to 5% by weight of at least one material selected from polyvinyl methyl ether, polyvinyl alcohol and polyvinylamine to prevent material separation.
15 to 55 weight percent cement-based binder, 15 to 55 weight percent of fine aggregate, 0.1 to 30 weight percent of admixture, and 5 to 40 weight percent of water,
The admixture includes 75 to 99% by weight of styrene-butadiene resin, 0.1 to 10% by weight of polymethyl methacrylate-butylacrylate resin, 0.1 to 10% by weight of polyvinylacetate ethylene resin and 0.1 to 10% by weight of polystyrene-butylacrylate resin. % And 0.01-5% by weight of methacrylamide,
The admixture is a cement mortar composition, characterized in that it further comprises 0.001 to 5% by weight of polycarbonate resin in order to improve the water resistance and wear resistance.
delete The cement mortar composition of claim 1, wherein the cement-based binder further comprises 0.001 to 5 wt% of at least one material selected from polycarboxylic acid, naphthalene, melamine, and lignin.
The cement mortar composition of claim 1, wherein the cement-based binder further comprises 0.001 to 6 wt% of at least one material selected from methyl cellulose, starch and gum.
The cement mortar composition of claim 1, wherein the cement-based binder further comprises 0.01 to 3% by weight of nylon fibers.
The method of claim 1, wherein the cement-based binder has a ratio (L / D) of the length (L) to diameter (D) in the range of 20 to 150, the macrofiber 0.01 to 0.01 made of at least one material selected from polyethylene and polypropylene Cement mortar composition further comprises 3% by weight.
Chipping and removing impurities or deterioration parts of the concrete slab;
Cleaning the chipped area;
Applying a primer for improving the adhesion between the concrete slab and the cement mortar composition according to claim 1, inhibiting water penetration and chlorine ion penetration, and improving water resistance and water resistance; And
Repairing method of the concrete structure comprising the step of curing after laying the cement mortar composition.
Cutting the cracks generated in the concrete structure into a V cut or a U cut using a concrete cutter;
Cleaning the impurities or slurry in the cut area;
Injecting repair method for a concrete structure comprising the step of curing by injecting the cement mortar composition of claim 1 to the cut portion.
Chipping the site where the micro-cracks generated by surface peeling, aggregate dropping, and plastic cracking due to scaling on the concrete structure are formed;
Cleaning impurities or slurries at the chipped sites;
Applying a primer to the chipped area; And
Surface treatment method of the concrete structure comprising the step of laying and curing the cement mortar composition according to claim 1 on the primer is applied.
Removing leitans or impurities from the surface of the concrete structure surface;
Applying a primer to the site from which the latans or impurities are removed;
Surface treatment treatment method of a concrete structure, comprising the step of laying and curing the cement mortar composition according to claim 1 on the top of the primer is applied to increase the commonness of the concrete structure.