KR101428984B1 - Early strength cement concrete composite with improved strength and durability, and repairing method of concrete structures using the composite - Google Patents

Abstract

The present invention relates to a rapidly-hardening cement concrete composition with improved strength and durability containing 3 to 30 wt% of inorganic binding material, 26 to 65 wt% of fine aggregate, 20 to 60 wt% of thick aggregate, 0.1 to 15 wt% of water, and 0.01 to 12 wt% of performance enhancer, in which the performance enhancer contains 30 to 90 wt% of styrene-acryl, 5 to 30 wt% of methyl metahcrylate, 1 to 25 wt% of butylacrylate, 0.1 to 20 wt% of butadiene, 0.01 to 10 wt% of isoprene, 0.01 to 10 wt% of polyvinyl methylether, 0.001 to 5 wt% of anti-foaming agent, and 0.001 to 5 wt% of emulsifying agent, and a concrete structure repair method using same. According to the present invention, the performance enhancer in which styrene-acryl, methyl metahcrylate, styrene-butadiene, butylacrylate, isoprene, and polyvinyl methylether are mixed is used so that concrete workability and durability are improved and, particularly, flexural strength and tensile strength are improved. Also, general portland cement, magnesium or calcium sulfo-aluminate, calcium aluminate, gypsum, silicate white clay, silicate soda, and moldenite are used so as to improve initial strength, long-term strength, durability, chloride resistance, freeze-thaw resistance, and the like.

Description

TECHNICAL FIELD The present invention relates to a cementitious cement composition having improved strength and durability and a method of repairing a concrete structure using the same.

The present invention relates to a rapid cementitious cement concrete composition with improved strength and durability and a method of repairing concrete structures using the same. More particularly, the present invention relates to a cementitious cementitious concrete composition having strength and durability And a method of repairing a concrete structure using the same.

Commonly used road pavement is concrete pavement method and asphalt pavement method.

Asphalt pavement is used for most of road pavements because it has ductility, excellent ride quality, low noise, and quick construction. However, because of the durability degradation due to heavy traffic, heavy traffic, It has a problem that the functionality as a road is easily deteriorated, frequent maintenance and maintenance costs increase, inconveniences caused by traffic interruption due to maintenance and addition of social costs. Especially, asphalt pavement is being used, and there is a risk of accidents due to many plastic deformation due to durability degradation in vehicle traffic roads and intersections.

Concrete pavement is rigid, has a large construction restriction on temperature and surrounding environment, takes a long period of curing, has cracks due to drying shrinkage, has unfavorable riding comfort and comfort but has excellent durability and reduced maintenance cost And some of them are applied to highway and medium-sized roads. In recent emergency repair work, polymer cement concrete with polymer emulsion added to concrete has been increasingly used to overcome the disadvantages of crude steel portland cement.

In general, polymer cement mortar is widely used for maintenance and reinforcement of areas where corrosion, erosion, etc. of the bottom plate of a bridge, the road surface and the lower part of a bridge occur frequently. The hardened Portland cement has the advantages of quick curing time and early strength development compared with portland cement. Contrary to this, penetration of chloride or water occurs, which causes corrosion of concrete.

Generally, there is a disadvantage in that when the concrete structure is manufactured or packaged, cracks are generated due to drying shrinkage, and the surface of the concrete structure is subjected to levitation due to bleeding, resulting in weak surface strength and durability.

1. Domestic Registered Patent No. 10-0755272 (Fast-curing cement composition for latex modified concrete) 2. Domestic Registered Patent No. 10-0873391 (quick-hard concrete composition, method for manufacturing the same, and method for repairing concrete pavement using quick-setting concrete composition)

The problem to be solved by the present invention is to improve the strength and durability of concrete by adding a performance improving agent and inorganic binder mixed with styrene-acrylic, methyl methacrylate, styrene-butadiene, butyl acrylate, isoprene and polyvinyl methyl ether The present invention provides a method for repairing a concrete structure using the same, and a method for repairing a concrete structure using the same, which is improved in strength and durability by reducing brittleness, tensile strength, initial strength, flame resistance and freezing and thawing resistance.

In order to accomplish the above object, the present invention provides a method for producing a steel sheet, which comprises 3 to 30% by weight of inorganic binder, 26 to 65% by weight of fine aggregate, 20 to 60% by weight of coarse aggregate, 0.1 to 15% Wherein the performance improving agent is selected from the group consisting of 30 to 90% by weight of styrene-acryl, 5 to 30% by weight of methyl methacrylate, 1 to 25% by weight of butyl acrylate, 0.1 to 20% by weight of butadiene, 0.01 to 10% 0.01 to 10 wt% of vinyl methyl ether, 0.001 to 5 wt% of an antifoam agent and 0.001 to 5 wt% of an emulsifier.

The inorganic binder is usually 15 to 85% by weight of Portland cement, 10 to 50% by weight of magnesium or calcium sulfoaluminate, 1.0 to 15% by weight of calcium aluminate, 1.0 to 15% by weight of gypsum, 0.01 to 10% 0.01 to 10% by weight of oxygen and 0.01 to 10% by weight of mordenite.

The inorganic binder may further contain 0.001 to 5% by weight of at least one promoter selected from the group consisting of calcium salts, chlorides, sulfates, potassium hydroxides, sodium hydroxides, carbonates, formic acid or salts thereof and lithium carbonate.

The inorganic binder may further contain 0.01 to 5% by weight of a water reducing agent.

The inorganic binder may further contain 0.001 to 5% by weight of a retarder.

The performance improving agent may further include 0.01 to 10% by weight of vinyl polypropionate.

The performance improving agent may further include 0.01 to 10% by weight of polypropylene.

According to the present invention, there is provided a method of manufacturing a concrete structure, comprising: a step of chipping a portion where concrete is deteriorated due to deterioration of a concrete structure using a crusher and a water jet to remove impurities and deteriorated portions; Applying a blooming or primer to the cementitious cementitious concrete composition to improve adhesion of the cementitious cementitious concrete composition to the concrete structure; and applying the quick-hardening cementitious concrete composition having improved strength and durability to the degraded portion And a step of applying a curing agent on the upper portion of the quick-curing cement concrete composition having improved strength and durability. The present invention also provides a method of repairing a concrete structure.

The primer may be composed of at least one material selected from styrene-butadiene rubber latex, polyacrylic ester, acryl, ethyl vinyl acetate, and the performance improving agent.

According to the present invention, by using a performance improving agent in which styrene-acrylic, methyl methacrylate, styrene-butadiene, butyl acrylate, isoprene, and polyvinyl methyl ether are mixed with a quick-setting cement concrete composition having improved strength and durability, The durability is improved, and particularly the bending strength and the tensile strength are improved.

The use of an inorganic binder improves initial strength and long-term strength development, durability, flame retardancy, freeze-thaw resistance and the like.

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 quick-curing cement concrete composition according to the preferred embodiment of the present invention is improved in strength and durability by 3 to 30% by weight of inorganic binder, 26 to 65% by weight of fine aggregate, 20 to 60% by weight of coarse aggregate, 0.1 to 15% 0.01 to 12% by weight of a performance improving agent.

The aggregate is divided into fine aggregate and fine aggregate. The aggregate having a particle diameter of 5 mm or less is referred to as a fine aggregate, and the aggregate having a particle diameter larger than 5 mm is classified as a coarse aggregate. The fine aggregate is preferably contained in 26 to 65 wt% in the fast-curing cement concrete composition having improved strength and durability, and the coarse aggregate is preferably contained in 20 to 60 wt% in the fast-curing cement concrete composition having improved strength and durability .

The inorganic binder is usually 15 to 85% by weight of Portland cement, 10 to 50% by weight of magnesium or calcium sulfoaluminate, 1.0 to 15% by weight of calcium aluminate, 1.0 to 15% by weight of gypsum, 0.01 to 10% 0.01 to 10% by weight of oxygen and 0.01 to 10% by weight of mordenite.

The inorganic binder may further contain 0.001 to 5% by weight of at least one promoter selected from the group consisting of calcium salts, chlorides, sulfates, potassium hydroxides, sodium hydroxides, carbonates, formic acid or salts thereof and lithium carbonate.

The inorganic binder may further contain 0.01 to 5% by weight of a water reducing agent.

The inorganic binder may further contain 0.001 to 5% by weight of a retarder.

The cement is usually Portland cement, and it is preferable to use those specified in KS. The cement is preferably contained in the inorganic binder in an amount of 15 to 85% by weight.

The magnesium or calcium sulfoaluminate is used for initial strength improvement and shrinkage reduction effect. The magnesium or calcium sulfoaluminate is preferably contained in an amount of 10 to 50% by weight based on the inorganic binder. When the content of magnesium or calcium sulfoaluminate is less than 10% by weight, the effect of inhibiting the strength and cracking is insufficient. When the content of magnesium or calcium sulfoaluminate exceeds 50% by weight, curing is promoted and workability is lowered.

The calcium aluminate is used for initial strength development by promoting the reactivity even at a low temperature. The calcium aluminate is preferably contained in an amount of 1.0 to 15% by weight based on the inorganic binder. If the content of the calcium aluminate is less than 1.0 wt%, the initial reactivity deteriorates and the initial strength development effect is insufficient. When the content exceeds 15 wt%, the reactivity is promoted, and the slump loss proceeds quickly, resulting in deterioration in workability and workability .

The gypsum is used for initial strength development. The gypsum can be anhydrous gypsum or anthracite. The gypsum is preferably contained in an amount of 1.0 to 15% by weight based on the inorganic binder. When the content is less than 1.0% by weight, the effect of improving the initial strength is weak. When the content is more than 15% by weight, excessive expansion may occur and durability may be deteriorated.

The kaolinite clay is used for potential hydraulic properties, long-term strength development and durability enhancement. Blast furnace slag, fly ash, or silica fume may be used in place of the kaolinite clay. It is preferable that the above-mentioned kaolin clay is contained in the inorganic binder in an amount of 0.01 to 10% by weight. When the content of the kaolinite clay is less than 0.01 wt%, the effect of improving the long-term strength of the quick-curing cement concrete composition having improved strength and durability is weak. When the content is more than 10 wt%, the workability is improved, .

Said potassium soda is used to improve water resistance. The sodium kosane is preferably contained in the inorganic binder in an amount of 0.01 to 10% by weight. If the content of sodium kosane is less than 0.01% by weight, the effect of improving water resistance is insufficient. If the content is more than 10% by weight, the water resistance may be improved but the strength may be lowered.

The mordenite is used for improving durability. The mordenite is preferably contained in an amount of 0.01 to 10% by weight based on the inorganic binder. When the content of the mordenite is less than 0.01 wt%, the durability is not improved. When the content of the mordenite is more than 10 wt%, the durability is improved but the workability is decreased.

The water reducing agent is used for improving the strength and durability. Examples of the water reducing agent include naphthalene-based, melamine-based, polycarboxylic acid-based water reducing agents and the like, but polycarboxylic acid based water reducing agents are preferably used. The water reducing agent is preferably contained in the inorganic binder in an amount of 0.01 to 3% by weight.

The retarder may be used for delaying rapid curing by gypsum to ensure workability for a certain period of time, and it is preferable that the retarder is contained in the inorganic binder in an amount of 0.001 to 5 wt%. As the delaying agent, generally well known substances can be used. Examples thereof include saccharides such as glucose, glucose, texturin and dextran, acids or salts thereof such as gluconic acid, malic acid, citric acid and citric acid, Or a salt thereof, a phosphonic acid or a derivative thereof, and a polyhydric alcohol such as glycerin.

The accelerator has a very fast reaction rate when it comes into contact with water, and when mixed with cement, it can obtain the compressive strength obtained within several days within a few hours. Such accelerators are generally known materials such as calcium formate, calcium chloride, calcium hydroxide, calcium salts such as calcium nitrate, magnesium chloride, magnesium salts such as magnesium sulfate, aluminum salts such as aluminum sulfate, lithium carbonate, lithium hydroxide, Lithium salt such as lithium sulfate, and the like, and the accelerator is preferably contained in the inorganic binder in an amount of 0.001 to 5% by weight.

The performance improving agent is used to improve the workability, strength and durability of concrete. The performance improving agent is used in order to improve the workability, strength and durability of concrete, and includes 30 to 90% by weight of styrene-acryl, 5 to 30% by weight of methyl methacrylate, 1 to 25% by weight of butyl acrylate, , 0.01 to 10 wt% of isoprene, 0.01 to 10 wt% of polyvinyl methyl ether, 0.001 to 5 wt% of defoamer, and 0.001 to 5 wt% of emulsifier.

The performance improving agent may further include 0.01 to 10% by weight of vinyl polypropionate.

The performance improving agent may further include 0.01 to 10% by weight of polypropylene.

The styrene-acryl is used to adjust the elasticity imparting, compressive strength and viscoelasticity of the film of the performance improver. The styrene-acryl is preferably contained in the performance improving agent in an amount of 30 to 90% by weight. When the content of styrene-acrylic is less than 30% by weight, the effect of improving the strength and viscoelasticity is inferior. When the content of styrene-acrylic is more than 90% by weight, the strength and viscoelasticity are improved but the viscosity is lowered.

The methyl methacrylate is used to improve strength and durability. The methyl methacrylate is preferably contained in the performance improving agent in an amount of 5 to 30% by weight. If the content of methyl methacrylate exceeds 30% by weight, the strength and durability are improved, but the viscosity is lowered and the workability is lowered and the price competitiveness is lowered. If the content of methyl methacrylate is less than 5% by weight, May be weak.

The addition of butyl acrylate to the performance improver improves the ductility and viscoelasticity of the performance improver film. The butyl acrylate is preferably contained in the performance improving agent in an amount of 1 to 25% by weight. If the content of butyl acrylate exceeds 25% by weight, the ductility and viscoelasticity are improved but the viscosity is lowered, resulting in poor workability and poor price competitiveness. If the content of butyl acrylate is less than 1% by weight, can do.

The addition of butadiene to the performance improver improves the ductility and warpage and adhesion strength of the performance improver film. The butadiene is preferably contained in the performance improving agent in an amount of 0.1 to 20% by weight. If the content of butadiene exceeds 20% by weight, the ductility, warpage and adhesion strength are improved but the viscosity is increased and the workability may be lowered. If the content of butadiene is less than 0.1% by weight, the effect of improving ductility, have.

The isoprene is used to control the dispersibility and the miscibility of the performance improver. The isoprene is preferably contained in the performance improving agent in an amount of 0.01 to 10 wt%. If the content of isoprene is more than 10% by weight, the dispersion stability and the mixing property are improved but the price competitiveness may be deteriorated. If the content of isoprene is less than 0.01% by weight, the dispersion stability and the effect of improving the mixing property may be weak.

The addition of polyvinyl methyl ether to the performance improver improves dispersibility and water resistance. The polyvinyl methyl ether is preferably contained in the performance improving agent in an amount of 0.01 to 10% by weight. If the content of the polyvinyl methyl ether is more than 10% by weight, the dispersibility and water resistance are improved but the viscosity is increased, resulting in poor workability and poor price competitiveness. If the content of polyvinyl methyl ether is less than 0.01% by weight, The effect of improving water resistance may be weak.

The defoaming agent is used to remove the pores in the concrete to increase the strength and durability of the concrete, and it is preferable to add 0.001 to 5% by weight to the performance improving agent. As the antifoaming agent, generally known substances such as an alcohol antifoaming agent, a silicone antifoaming agent, a fatty acid antifoaming agent, an oil antifoaming agent, an ester antifoaming agent and an oxyalkylene antifoaming agent can be used. 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 agent include kerosene, animal and plant oil, castor oil, and the ester-based antifoaming agents include solitol trioleate and glycerol monoricinolate. Examples of the oxyalkylene antifoaming agents include polyoxyalkylene, acetylene ethers, polyoxyalkylene diazoxide esters, polyoxyalkylene alkylamines, and the like. Examples of the antifoaming agent include glycol.

The emulsifier may be classified into cation (C), anionic (A), and nonionic (N) based on the ion of the emulsifier and may be classified into Rapid Setting (RS) series, Medium Setting ; MS) series, and Slow Setting (SS) series. RS (C) -3 or RS (C) -4, which is a cationic emulsifier of the rapid condensation (RS) series, is used, and it is preferable to use a cationic emulsifier which is intermediate between the medium speed and the full- The emulsifier is used to improve workability, strength and durability by lowering the water-cement ratio. The emulsifier is preferably contained in the performance improving agent in an amount of 0.001 to 5% by weight.

In addition, the performance improving agent may further include vinyl polypropionate to improve the adhesive strength and water resistance. The polypropionic acid vinyl is preferably contained in the performance improving agent in an amount of 0.01 to 10% by weight.

In addition, the performance improving agent may further include polypropylene to improve water resistance. The polypropylene is preferably contained in the performance improving agent in an amount of 0.01 to 10% by weight.

The quick-hard cement concrete composition having improved strength and durability according to a preferred embodiment of the present invention is prepared by mixing 3 to 30% by weight of inorganic binder, 26 to 65% by weight of fine aggregate and 20 to 60% by weight of coarse aggregate into a mixer, , Followed by further mixing 0.1 to 15% by weight of water with 0.01 to 12% by weight of the performance improving agent and stirring for a predetermined time (for example, 1 to 10 minutes).

The method of repairing a concrete structure according to a preferred embodiment of the present invention includes the steps of removing impurities and deteriorated portions by chipping a portion where a concrete structure is deteriorated or impurities are attached using a crusher or a water jet, Applying a blooming or primer to the area of the cementitious cementitious concrete structure, restoring a section of the area degraded by the cementitious cementitious concrete composition with improved strength and durability, And applying the composition with a curing agent on top of the composition.

Hereinafter, the term "concrete structure" is used to mean any structure made of concrete, such as a road surface, a bridge bridge, a concrete slab of a bridge, and a bridge bottom.

The blooming is carried out in order to enhance the adhesion strength of the quick-curing cement concrete composition having improved strength and durability to an integrated behavior with the concrete structure. The blooming material is mixed with 10 to 80% by weight of the inorganic binder and 15 to 75% by weight of the fine aggregate in a mixer, stirring the mixture intensively, mixing 0.1 to 15% by weight of water with 0.01 to 20% For example, 1 to 10 minutes) is preferably used.

The primer may be selected from the group consisting of styrene butadiene rubber latex, polyacryl ester (PAE), acryl and ethylene vinyl (meth) acrylate, which facilitates adhesion of a quick-setting cement concrete composition having improved strength and durability to a concrete structure Ethylene (ethylene vinyl acetate) (EVA), and the performance improving agent. At this time, the solid content of the primer is preferably lowered to about 10% by weight. When it is used in an amount exceeding 10% by weight, the film thickness becomes thick, and adhesion performance may be deteriorated.

Hereinafter, embodiments of the fast-curing cement concrete composition with improved strength and durability according to the present invention will be more specifically shown, and the present invention is not limited by the following embodiments.

17% by weight of inorganic binder, 43% by weight of fine aggregate and 34% by weight of coarse aggregate were added to a mixer, and the mixture was forcedly stirred. Then, 3% by weight of water and 3% by weight of a performance improving agent were further mixed, Speed cementitious cement concrete composition.

At this time, the inorganic binder is usually 45 wt% of Portland cement, 30 wt% of magnesium sulfoaluminate, 5 wt% of calcium aluminate, 5 wt% of gypsum, 10 wt% of K white clay, 2 wt% of K oxygen, 0.5% by weight of a water reducing agent, 0.5% by weight of an accelerator and 0.5% by weight of a retarder were mixed and used. A polycarboxylic acid-based water reducing agent was used as the water reducing agent, lithium carbonate was used as the accelerator, and citric acid was used as the retarding agent.

The performance improving agent was a mixture of 90 wt% of styrene-acrylic, 5 wt% of methyl methacrylate, 1 wt% of butyl acrylate, 1 wt% of butadiene, 1 wt% of isoprene, 1 wt% of polyvinyl methyl ether, 0.5% by weight were mixed and used. The antifoaming agent used was glycol, and RS (C) -3 was used as the emulsifying agent.

17% by weight of inorganic binder, 43% by weight of fine aggregate and 34% by weight of coarse aggregate were added to a mixer, and the mixture was forcedly stirred. Then, 3% by weight of water and 3% by weight of a performance improving agent were further mixed, Speed cementitious cement concrete composition.

At this time, the inorganic binder is usually 45 wt% of Portland cement, 30 wt% of magnesium sulfoaluminate, 5 wt% of calcium aluminate, 5 wt% of gypsum, 10 wt% of K white clay, 2 wt% of K oxygen, 0.5% by weight of a water reducing agent, 0.5% by weight of an accelerator and 0.5% by weight of a retarder were mixed and used. A polycarboxylic acid-based water reducing agent was used as the water reducing agent, lithium carbonate was used as the accelerator, and citric acid was used as the retarding agent.

The performance improver was a mixture of 85 wt% styrene-acryl, 6 wt% methyl methacrylate, 2 wt% butyl acrylate, 2 wt% butadiene, 2 wt% isoprene, 2 wt% polyvinyl methyl ether, 0.5 wt% 0.5% by weight were mixed and used. The antifoaming agent used was glycol, and RS (C) -3 was used as the emulsifying agent.

17% by weight of inorganic binder, 43% by weight of fine aggregate and 34% by weight of coarse aggregate were added to a mixer, and the mixture was forcedly stirred. Then, 3% by weight of water and 3% by weight of a performance improving agent were further mixed, Speed cementitious cement concrete composition.

At this time, the inorganic binder is usually 45 wt% of Portland cement, 30 wt% of magnesium sulfoaluminate, 5 wt% of calcium aluminate, 5 wt% of gypsum, 10 wt% of K white clay, 2 wt% of K oxygen, 0.5% by weight of a water reducing agent, 0.5% by weight of an accelerator and 0.5% by weight of a retarder were mixed and used. A polycarboxylic acid-based water reducing agent was used as the water reducing agent, lithium carbonate was used as the accelerator, and citric acid was used as the retarding agent.

The performance improving agent was a mixture of 80 wt% of styrene-acryl, 8 wt% of methyl methacrylate, 3 wt% of butylacrylate, 3 wt% of butadiene, 3 wt% of isoprene, 3 wt% of polyvinyl methyl ether, 0.5% by weight were mixed and used. The antifoaming agent used was glycol, and RS (C) -3 was used as the emulsifying agent.

Comparative Examples are shown in order to more easily grasp the characteristics of Examples 1 to 3, and Comparative Examples 1 to 2 show a general Portland cement concrete composition and a cement concrete composition widely used at present will be.

[Comparative Example 1]

17% by weight of Portland cement, 43% by weight of fine aggregate, 34% by weight of coarse aggregate and 6% by weight of water were put into a mixer and forcedly stirred to prepare a concrete composition.

[Comparative Example 2]

17% by weight of Portland cement, 43% by weight of fine aggregate, and 34% by weight of coarse aggregate were added to a mixer and forced stirring. Then, 3% by weight of water and 3% by weight of styrene-acrylic were further mixed and stirred again for 2 minutes to obtain polymer cement concrete A composition was prepared.

The following test examples show experimental results in which the characteristics according to the present invention are compared with the characteristics of Comparative Example 1 and Comparative Example 2 in order to more easily grasp the characteristics of Examples 1 to 3 according to the present invention .

[Experimental Example 1]

The quick-curing cement concrete compositions prepared according to Examples 1 to 3 with improved strength and durability and the cement concrete compositions prepared according to Comparative Examples 1 and 2 were subjected to a slump test according to the method defined in KS F 2402 The degree of kneading). The slump test is to test the quality of the dough such as the flue and viscosity of the concrete. The larger the value, the better the workability in putting the concrete.

Table 1 below shows the change in slump over time.

division Slump (cm) Immediately after stirring After 20 minutes After 30 minutes After 40 minutes Example 1 20 18 15 12 Example 2 20 18 16 13 Example 3 21 20 18 16 Comparative Example 1 16 12 10 7 Comparative Example 2 19 16 13 10

As shown in the above Table 1, the quick-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 had better workability than the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 .

[Test Example 2]

The fast-curing cement concrete compositions with improved strength and durability produced according to Examples 1 to 3 and the concrete compositions prepared according to Comparative Examples 1 and 2 were subjected to a compressive strength test according to the method specified in KS F 2405 .

Table 2 below shows the change in compressive strength with time.

division Compressive strength (kgf / ㎠) After 12 hours After 24 hours 3 days later After 28 days Example 1 255 295 339 420 Example 2 268 305 350 445 Example 3 272 311 359 460 Comparative Example 1 - - 256 400 Comparative Example 2 - - 260 406

As shown in Table 2 above, the fast-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 had a compressive strength higher than that of the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 Respectively.

[Test Example 3]

The flexural strength was measured according to the method defined in KS F 2408 for the quick-curing cement concrete composition improved in strength and durability and the concrete composition prepared in Comparative Example 1 and Comparative Example 2 prepared according to Examples 1 to 3 The results are shown.

Table 3 below shows the changes in bending strength with time.

division Bending strength (kgf / ㎠) After 12 hours After 24 hours 3 days later After 28 days Example 1 52 57 62 70 Example 2 55 59 64 73 Example 3 57 62 68 76 Comparative Example 1 - - 40 54 Comparative Example 2 - - 44 64

As shown in the above Table 3, the quick-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 has higher flexural strength than the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 Respectively.

[Test Example 4]

The adhesive strengths of the cement concrete compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 2 were measured according to KS F 2762, and the results are shown in Table 4.

division Adhesion strength (kgf / cm 2) After 12 hours After 24 hours 3 days later After 28 days Example 1 16 18 20
22 Example 2 17 19 21 23 Example 3 19 20 23 25 Comparative Example 1 - - 11 17 Comparative Example 2 - - 13 20

As shown in Table 4 above, the fast-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 had higher adhesion strength than the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 Respectively.

[Test Example 5]

A quick-curing cement concrete composition improved in strength and durability, prepared according to Examples 1 to 3 and a concrete composition prepared according to Comparative Example 1 and Comparative Example 2 were prepared according to the method specified in KS F 4004 (cement brick) The measurement results of the water absorption rate are shown. If the water absorption rate is high, impurities or water penetrate into the interior of the concrete, the porosity increases in the interior of the concrete, thereby causing a problem of causing damage to the structure. That is, the lower the absorptivity, the more the strength of the concrete is improved after curing.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Absorption Rate (%) 1.0 0.8 0.5 3.1 1.3

As shown in Table 5, the quick-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 had a lower water absorption rate than the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 .

[Test Example 6]

The quick-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 and the concrete composition prepared according to Comparative Example 1 and Comparative Example 2 were subjected to a freeze-thaw resistance test according to the method defined in KS F 2456 . Fig. 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 6 shows the durability indices 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 89 90 91 58 85

As shown in Table 6 above, the fast-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 has a durability index higher than that of the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 It can be seen that the durability is improved.

[Test Example 7]

The fast-curing cement concrete compositions with improved strength and durability produced according to Examples 1 to 3 and the concrete compositions prepared according to Comparative Example 1 and Comparative Example 2 were evaluated by KS F 2424 (length change test method of concrete) The drying shrinkage was measured and the results are shown in Table 7 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Length change rate
(%) 0.03 0.03 0.02 0.10 0.07

[Test Example 8]

The quick-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 and the concrete composition prepared according to Comparative Example 1 and Comparative Example 2 were evaluated by JIS A 1171 (Test Method of Polymer Cement Mortar) The results are shown in Table 8. < tb > < TABLE >

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Neutralization depth (mm) 0.4 0.3 0.2 1.3 0.7

As shown in Table 8 above, the fast-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 had a higher neutralization penetration depth than the cement concrete compositions prepared according to Comparative Examples 1 and 2 And the resistance to neutralization was high.

[Test Example 9]

The fast curing concrete composition with improved strength and durability and the concrete composition prepared according to Comparative Example 1 and Comparative Example 2 prepared according to Examples 1 to 3 were tested according to JIS A 1171, Are shown in Table 9 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Chloride ion
Penetration depth (mm) 1.2 1.0 0.9 3.2 1.6

As shown in Table 9 above, the fast-curing cement concrete composition improved in strength and durability produced according to Examples 1 to 3 has a higher chloride ion permeability than the cement concrete composition prepared according to Comparative Example 1 and Comparative Example 2 And the depth was small and it was confirmed that there was a high resistance to salting.

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 (8)

The performance improving agent is a mixture of styrene-acryl 30 to 30 weight% of inorganic binder, 26 to 65 weight% of fine aggregate, 20 to 60 weight% of coarse aggregate, 0.1 to 15 weight% of water and 0.01 to 12 weight% By weight of polyvinyl butyral, 0.01 to 10% by weight of polyvinyl butyral, 0.01 to 10% by weight of polyvinyl butyral, 0.01 to 10% by weight of methyl methacrylate, 1 to 25% by weight of butyl acrylate, 0.1 to 20% by weight of butadiene, Wherein the inorganic binder comprises 15 to 85% by weight of Portland cement, 10 to 50% by weight of magnesium or calcium sulfoaluminate, 1.0 to 15% by weight of calcium aluminate, 1.0 to 15% by weight of gypsum, 0.01 to 10% by weight of kaolinite, 0.01 to 10% by weight of oxygen and 0.01 to 10% by weight of mordenite,
Wherein the inorganic binder further comprises 0.001 to 5% by weight of at least one accelerator selected from calcium salts, chlorides, sulfates, potassium hydroxides, sodium hydroxides, carbonates, formic acid or its salts and lithium carbonate,
The inorganic binder may further comprise 0.01 to 5% by weight of a water reducing agent, or may further comprise 0.001 to 5% by weight of a retarder,
Wherein the performance improving agent further comprises 0.01 to 10% by weight of vinyl polypropoxylate or 0.01 to 10% by weight of polypropylene. delete delete delete Removing impurities and deteriorated portions by chipping a portion where concrete is deteriorated due to deterioration of a concrete structure using a crusher and a water jet,
Applying a blooming or primer to the deteriorated portion of the concrete structure to facilitate adhesion of the quick-curing cement concrete composition having improved strength and durability as set forth in claim 1;
A method for manufacturing a cementitious cementitious concrete composition, comprising the steps of: (1) restoring a section of a deteriorated portion by applying a quick-setting cementitious concrete composition having improved strength and durability,
And applying the upper part of the quick-curing cement concrete composition with the cured material improved in the punched strength and durability,
10 to 80% by weight of the inorganic binder as described in claim 1 and 15 to 75% by weight of the fine aggregate are added to a mixer, and the mixture is forcibly agitated. Thereafter, 0.1 to 15% by weight of water and 0.01 to 20% %, And stirring the mixture for 1 to 10 minutes. 6. The method of claim 5,
Wherein the primer is made of at least one material selected from the group consisting of styrene-butadiene rubber latex, polyacrylic ester, acryl, ethyl vinyl acetate, and the performance improving agent according to claim 1. delete 6. The method of claim 5,
The primer may be a styrene butadiene rubber latex, a polyacrylic ester (PAE), a polyacrylic acid ester (PAE), or the like, which facilitates adhesion of a quick-setting cement concrete composition having improved strength and durability to the concrete structure, Acrylic and ethylene vinyl acetate (EVA). The method for repairing a concrete structure according to claim 1,