KR101862611B1 - Concrete structure repairing mortar and repairing method - Google Patents

Abstract

The present invention relates to a mortar composition for repairing concrete structures including a Portland cement, a silica sand, a flooring material, a pozzolan powder, a calcium sulfoaluminate, a fluidizing agent, a re-oiling type polymer, and a method for repairing a concrete structure by a continuous mixing type mixer.

Description

Technical Field [0001] The present invention relates to a mortar composition for repairing a concrete structure, a coating composition for protecting a concrete, and a method for repairing a concrete structure,

The present invention relates to a mortar composition for repairing concrete structures using a bottom ash, a coating composition for concrete protection based on modified acrylic, and a method for repairing a concrete structure using an auger type mixer of continuous mixing type.

When building civil and architectural structures, the most commonly used material with steel is concrete.

Concrete is used to construct buildings by mixing cement, aggregate, and water, or to construct various civil engineering structures such as roads, bridges, harbors, dams, tunnels, and circular pipes. However, as time elapses during use, these concrete structures deteriorate in durability and usability in the long term due to deterioration of structures due to corrosion, expansion, neutralization, alkali aggregate reaction, chemical corrosion and corrosion corrosion of steel due to penetration of water. As the deterioration of these structures continues, it may lead to the collapse of the structure. Therefore, the concrete structures should be continuously managed and repaired.

If the surface of the structure is peeled or cracked, it is easy to move the deterioration factor to promote the progress of deterioration. Therefore, in order to maintain the stability and performance of the reinforced concrete structure, And to improve the durability life and prevent performance degradation.

In this case, a typical method of repairing concrete structures is to charge concrete with a deterioration factor such as peeling or detachment of the cross-section of the structure, and then to charge or spray the cross-sectional restorative material to restore its original performance and shape , There is a method of coating the concrete surface.

Mortar of various materials including aggregate part, binder part and other additives is used to recover the section, but cracks are generated at the early stage of curing after application and peeling phenomenon occurs due to poor adhesion at the construction interface, There is a problem in that adhesion to a coating agent becomes poor.

In case of repair mortar for repairing the concrete section, it is the most problem that the maintenance mortar is put in the deteriorated existing concrete section, and the moisture of the repair mortar is absorbed in the construction section of the existing concrete when it is cured, It is the point where the curing failure occurs at the old interface.

That is, there is a problem that the repair mortar for repairing the concrete section is rapidly dried and settled (the cement does not bond to each other and exists in the form of a powder with a sparse texture). As a result, the repair mortar and the existing concrete The interface adhesion force with the surface is lowered, which causes a defect such as lifting.

There is a method of blocking moisture, salt, noxious gas and chemical substances which cause durability by coating paint on concrete surface to form coating film. The coating is widely used to make up more than 65% of the methods because it is easy to construct and has excellent effect on prevention of performance deterioration and is recognized as an efficient method for facility repair. Epoxy, vinyl ester, A method of forming a coating film using a coating material such as a rubber, a chlorinated rubber or a urethane has been developed.

However, the coating agent used in the conventional coating method has problems such as bacterial reproduction when most of the organic matter comes into contact with water, and problems such as lifting and dropping of the coating film in the water reservoir, purified water, .

On the other hand, in a thermal power plant, coal pulverized to about 40 to 80 μm is injected into the furnace at high speed with hot air, and is instantaneously burned in a floating state at a temperature of 1,500 ° C. to 200 ° C. After burning, ash). The coal ash is divided into fly ash and bottom ash according to the place where it is collected after burning. It is attached to the wall, superheater, reheater, etc. It is a floor material that is collected by shredding in the range of 0.1 ~ 2.5mm by the grinder installed in the lower part of the hopper and transferred to the treatment plant.

The amount of coal ash that was expected to be discharged by about 10 million tons in 2015 is gradually increasing. In the case of fly ash, most of it is recycled as concrete admixture and other materials. However, the demand for flooring that accounts for 20% of total coal ash Most of them are landfilled.

Patent Literature 0001 relates to a repair method of a slope and a curved surface structure using shotcrete. In the deteriorated part removing step of spraying pressurized water by a high water pressure on a concrete slope or a deteriorated portion of a curved surface by a pressurized water injection device, ; And a shotcrete pouring step of pouring the shotcrete composition onto the concrete slope from which the deteriorated part has been removed, wherein the shotcrete composition comprises 440 to 480 kg / m3 of a binder including cement and silica fume; 7 to 10 parts by weight of the silica fume; 0.01 to 0.05 parts by weight of a liquid AE; 0.5 to 1.5 parts by weight of a liquid high performance fluidizing agent; (W / B) is 35 to 40 parts by weight, and the amount of air is 10 to 20% by volume.

Korean Patent Registration No. 10-1073969

In order to solve the problems of the conventional art as described above, it is an object of the present invention to provide a mortar composition for repairing a concrete structure, a concrete coating composition for protecting concrete based on denatured acrylic and a concrete composition for a concrete using an auger type mixer And a method for repairing a structure.

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According to the present invention, there is provided a method of repairing a concrete structure, comprising the steps of: a) breaking a concrete which is deteriorated in an existing concrete structure to remove unusable concrete; b) chipping step of irregularly smoothing the surface of the exposed existing concrete structure; c) a surface treatment step for removing foreign matter, old film, and deterioration factor existing on the chipping surface of the existing concrete structure; d) 25 to 30 parts by weight of one kind of ordinary Portland cement; 7 to 18 parts by weight of a silica sand having an average particle diameter of 0.60 to 0.85 mm; 15 to 25 parts by weight of a silica sand having an average particle diameter of 0.25 to 0.60 mm; 20 to 45 parts by weight of a bottom material having an average particle diameter of 0.25 to 0.85 mm; 8 to 16 parts by weight of pozzolan powder; 3 to 5 parts by weight of calcium sulfoaluminate; 0.2 to 1.2 parts by weight of a fluidizing agent; 1.5 to 4.0 parts by weight of a re-forming type polymer; e) a curing step of curing the repair mortar; f) 18 to 35 parts by weight of water; 60 to 80 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; 0.5 to 2 parts by weight of a tackifier; and a primer layer applying a coating composition comprising: g) applying a mid layer onto the primer layer; h) applying an upper layer onto the intermediate layer, wherein the intermediate layer and the upper layer comprise 5 to 10 parts by weight of water; 0.2 to 2 parts by weight of an additive; 10 to 25 parts by weight of calcium carbonate; 0.1 to 0.8 parts by weight of silica fume; 0.1 to 2 parts by weight of pigment; 5 to 15 parts by weight of titanium dioxide; 40 to 60 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; From 0.5 to 2 parts by weight of texanol; 0.1 to 0.5 parts by weight of a surfactant; 0.1 to 0.5 parts by weight of an additive; And 0.1 to 1 part by weight of an antifoaming agent. The present invention also provides a method of repairing a concrete structure,

The step a) may be carried out by injecting high-pressure water into the deteriorated portion of the existing concrete structure by the high-pressure water injection device.

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The auger type mixer includes a silo 40, a mixing unit 100, a transfer unit 200, and a conveying unit 200. The auger type mixer is a continuously mixing type auger type mixer capable of mixing and transporting the maintenance mortar in step d) And a discharge unit 300. The mixing unit 100 includes a rotating shaft 10 formed in the silo 40; A plate blade 110 fixed to an outer surface of the rotary shaft 10; And a breaking hole 120 formed in the plate blade 110.

The mortar composition for repairing a concrete structure according to the present invention includes a bottom material, and the micropores of the bottom material fills the compounded water, thereby preventing the problem of condensation that occurs due to rapid drying of the repair mortar.

When a primer is applied to a mortar containing a bottom material, fine voids caused by the bottom material act as a female thread (space) through which the primer can infiltrate. Primer penetrates into the micropores in the bottom material to serve as a male thread, Is physically integrated, and the coating does not peel off even after a long period of time.

The repair mortar and the coating material of the present invention can provide a repair section with improved performance such as strength, alkali resistance, chemical resistance, resistance to carbonation, anticorrosion, water repellency, and anti-freeze property.

By using auger type mixer with continuous mixing method, it is possible to prevent the heterogeneous mixing and condensation of materials, which are often caused by mixing with a conventional cylindrical mixer, .

Mixing and transferring are continuously performed by a continuous mixing type auger type mixer, so process control is easy and labor is saved.

The injection of mortar mixture through the silo, the mixing of the mortar with the mixer, and the conveying and discharging of the mortar are performed at the same time, so that the operation is efficient and the construction period is greatly shortened.

1 and 2 are SEM (1000 times) photographs of the flooring material.
3 is a cross-sectional view of an auger type mixer of continuous mixing type.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification. Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Mortar Composition for Repairing Concrete Structures>

The mortar composition for repairing concrete structures of the present invention includes one kind of ordinary Portland cement, silica sand, flooring material, pozzolan powder, calcium sulfoaluminate, fluidizing agent and re-oiling type polymer.

Specifically, the one kind of ordinary Portland cement contains 25 to 30 parts by weight; Wherein the silica sand has a silica sand having an average particle diameter of 0.60 to 0.85 mm in an amount of 7 to 18 parts by weight and a silica sand in an average particle diameter of 0.25 to 0.60 mm in an amount of 15 to 25 parts by weight; 20 to 45 parts by weight of the bottom material having an average particle diameter of 0.25 to 0.85 mm; 8 to 16 parts by weight of the pozzolan powder; 3 to 5 parts by weight of calcium sulfoaluminate; 0.2 to 1.2 parts by weight of the fluidizing agent; And 1.5 to 4.0 parts by weight of the resorbable polymer.

The properties of each material will be described in detail below.

ㅇ Class 1 ordinary Portland cement

It is also possible to use 5 grade cement as a core material of mortar to improve chemical resistance and salt resistance. When the amount of cement is too small, the bonding strength of the mortar weakens and the strength and durability are deteriorated. When too much amount of cement is used, a lot of hydration heat is generated, and cracks may occur due to plastic contraction or the like. In the present invention, the amount of the cement is set to 25 to 30 parts by weight because the pozzolan powder plays a role as a binder.

ㅇ Silica sand

No. 6 silica having a particle diameter of 0.25 to 0.60 mm and silica No. 5 having a diameter of 0.60 to 0.85 mm were applied so as to have a uniform particle size distribution and to increase the filling rate of particles to design more compact physical properties.

ㅇ Flooring

The bottom ash is collected by the small particles gathered together and collected at the bottom of the hopper. There are innumerable micropores inside the aggregated particles and these pores are also used as lightweight materials and can be used as high water holding capacity and breathable materials.

It is porous, has somewhat less density than natural aggregate, and has high water absorption. 1 and 2 are photographs of SEM (1000 times) photographs of the flooring material.

The fine particles are solidified and have a shape similar to that of aggregate. The absorption rate is high (4 to 15%) and it is possible to prevent curing failure at the new-spherical interface.

As a result of the problem that the existing concrete interface absorbs a large number of compounding water, the repairing mortar sharply dries and coagulates (the cement does not bind to each other and exists in the form of a casting powder), and the interfacial adhesion with the existing concrete decreases, The flooring material absorbs the amount of the compounding agent in the maintenance mortar and maintains the water retention property by supplying water to the maintenance mortar during the curing period after the pouring, It can be done well.

By keeping the water retentivity, the adhesive force at the interface with the existing concrete can be maintained and integrated, and the crack generating factor (drying shrinkage, etc.) of the concrete is removed.

In addition, the fine passage type pores generated by moisture discharge during the curing process act as a female thread (space) through which the concrete protective coating can permeate. After the maintenance mortar curing, the primer penetrates into the micropores in the bottom material and acts as a male thread, so that the primer coat and the mortar are physically integrated.

The particle size of the bottom layer was 0.25 to 0.85 mm, which was the same as the entire particle size range of the silica sand, and the amount of the component was 20 to 45 parts by weight.

If the amount is less than 20 parts by weight, the effect of improving the integrity of the coating with the primer coating is insignificant. If the amount exceeds 45 parts by weight, the strength of the mortar may be weak after hardening.

ㅇ Pozzolan powder

As the pozzolanic material, blast furnace slag powder and silica fume are most suitable. It is usually used as a substitute for Portland cement. It is less expensive than cement and can suppress hydration heat. The internal structure becomes dense due to long - term hydroponics, and durability such as water - resistance, chemical resistance and alkali - resistance are improved. In addition, there is an effect (excellent in empirical) when the finish is finished.

When the amount is less than 8 parts by weight, the effect is insignificant. When the amount is more than 16 parts by weight, the initial strength of the mortar may be lowered.

ㅇ Calcium sulfoaluminate

It is used as an expansion agent by the production of ettringite and the reaction of free lime. It is possible to reduce the shrinkage part (for example, drying shrinkage, autogenous shrinkage and plastic shrinkage) due to the cement hydration reaction, thereby preventing cracking of the concrete with weak tensile strength.

When the amount is less than 3 parts by weight, the effect is insignificant. When the amount is more than 5 parts by weight, the amount of swelling increases and expansion cracks may occur.

ㅇ Fluidizing agent

Mortar binders and fine silica sand. The polymer has surface activity and is adsorbed on the surface of the material. The fluidizing agent forms a lubricating film between the particles, thereby reducing the mutual adhesion between the components and exhibiting improved flow characteristics. These properties make it possible to reduce the amount of water used, thereby improving the strength of the mortar and increasing the flow performance to facilitate the work. Based naphthalene-based, melamine-based, polycarboxylic-based or the like can be used.

O Re-polymerized polymer

A dispersed material prepared by spray drying a liquid resin is dispersed in water to form a safe liquid resin. The powdered resin dispersed in water forms an irreversible polymer film that does not dissolve in water after drying. It is mixed with cement like liquid resin to improve tensile and flexural strength. It is also used as an organic or inorganic base agent such as pvc, Thereby improving adhesion. It also controls the viscosity of the hardened mortar to reduce bleeding.

<Coating composition for concrete protection>

Concrete protection coatings generally have a smaller particle size of the resin, which can form a dense film at the time of film formation and can easily enter the gap between the pillars of the coating material to form a film, thereby more firmly holding the fillers, It helps to form a film. Generally, the particle size of acrylic emulsion resin is about 300 ~ 400 ㎚. In the case of EVA (ethylene-vinyl acetate copolymer) resin which is widely used for concrete, its particle size is about 400 ~ 500 ㎚ relatively larger than acrylic resin. Therefore, it is possible to form a more robust film by controlling the particle size of the resin used in the coating preparation.

In order to improve the water resistance, the coating agent for protecting concrete used in the present invention is designed to have a particle size of 100-150 nm by controlling the amount of emulsifier and the amount of the initial reaction so that the particle size is smaller than that of a general acryl emulsion, use. In addition, functional monomers with OH groups are used to form strong hydrogen bonds during drying to form water-resistant coatings in general.

In the present invention, the concrete protective coating agent is applied by a method of sequentially applying three kinds of materials such as primer, middle, and top. The primer penetrates the concrete surface and the mortar and attaches to the intermediate coating. The midway shows the function of blocking the penetration of harmful factors from the outside, ions such as salinity, and the like in the midway between the coating film and the coating film.

The top coat is a finish coating layer which has the ability to resist ultraviolet rays, rain and the like, to ensure the barrier against external corrosion-causing substances, and to enhance beauty.

The conventional coating agent is a two-part oil-based coating material containing a volatile organic solvent such as benzene, toluene, and xylene, which is harmful to the human body or has a risk of deteriorating the water quality. The coating material for concrete protection of the present invention, however, Is limited by the use of organic compounds (VOCs).

Therefore, it is possible to secure the safety of the operator in an enclosed space and further secure the safety of the user. In addition, most of recent paints are two-component type coatings in which a main component and a hardening agent are separated, and the time required for the mixing is long, so that the quality of the coating may vary depending on the mixing method and ratio. It is possible to prevent deterioration of the construction quality due to non-homogeneous mixing of the materials.

18 to 35 parts by weight of water used as a solvent in the case of primer (primer); 60 to 80 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; And 0.5 to 2 parts by weight of a technoacid used as a film forming agent for forming a coating film.

5 to 10 parts by weight of water used as a solvent in the case of medium and high temperatures; 0.2 to 2 parts by weight of an additive for enhancing the dispersibility of raw materials; 10 to 25 parts by weight of calcium carbonate used as a pigment for enhancing the covering and the beauty of the coating film; 0.1 to 0.8 parts by weight of silica fume; 0.1 to 2 parts by weight of pigment; 5 to 15 parts by weight of titanium dioxide; 40 to 60 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; 0.5 to 2 parts by weight of a technoacid used as a film forming agent for forming a coating film; 0.1 to 0.5 parts by weight of a surfactant used as a dispersing agent for activating the dispersion of the material; 0.1 to 0.5 parts by weight of an additive for adjusting the viscosity of the coating film to form a watertight coating layer and a flat film; 0.1 to 1 part by weight of an antifoaming agent used for the purpose of removing bubbles by the use of a polymer.

As an additive for increasing the dispersibility of the raw materials, at least one of a fatty acid-modified copolymer, sodium polyacrylic acid and sodium silicate may be used. As the pigment, at least one or more of titanium dioxide, carbon black, iron oxide, phthalocyanine, zinc oxide, pseudobrookite, An aqueous dispersion of paraffin may be used as an additive for adjusting the viscosity of the coating film to form a watertight coating layer and a flat film.

<Continuous mixing type auger type mixer>

Referring to FIG. 3, the continuous mix type auger type mixer of the present invention, which is capable of transporting mortars while mixing, will be described.

The continuous mixing type auger type mixer of the present invention comprises a mixing unit 100, a feeding unit 200, and a discharging unit 300.

When mixing materials and mixing water constituting the mortar are put into the silo 40 and operated, the mixture is mixed in the mixing unit 100 and moved to the transfer unit 200.

The mortar transferred to the transfer unit 200 is discharged through the discharge unit 300 by the operation of the screw of the transfer unit, and is moved to the high pressure transfer pump.

After the mixing is performed in the mixing portion, when the mortar moves to the transfer portion 200, a new mortar combination material is introduced into the mixing portion to start mixing. At this time, the transfer of the mortar is still proceeding continuously in the transfer part.

That is, the mortar mixture material that has been introduced first is discharged from the transfer section to the discharge section, and at the same time, the mixing of the new mortar mixture material proceeds in the mixing section. In this way, the process of injecting, mixing, and transferring the mortar mixture is continuously performed, so that the workload of the worker is reduced, and the time required for the production of the mortar and the repair work of the structure is drastically shortened.

Hereinafter, configurations of the continuous mixing type auger type mixer of the present invention will be described in detail.

The mixing part (100)

FIG. 3 shows the overall configuration of the auger type mixer of the continuous mixing type of the present invention.

The mixing section 100 is formed near the bottom surface of the silo 40 and includes a rotating shaft 10 and a plate blade 110 fixed to an outer surface of the rotating shaft. (120) formed on the plate blade (110).

The rotating shaft 10 may be formed as one unit and used commonly in the mixing unit 100 and the transfer unit 200. 3, the mixing unit 100 may be driven separately from the transfer unit 200, and the transfer unit 200 may be driven separately.

The plate blade 110 is fixed to the outer surface of the rotating shaft. The longitudinal direction of the plate blade 110 and the longitudinal direction of the rotating shaft are perpendicular to each other. The outer surface of the plate blade 110 is parallel to the longitudinal direction of the rotating shaft And the outer surface of the plate blade 110 is obliquely inclined at a predetermined angle with respect to the longitudinal direction of the rotating shaft.

When the outer surface of the plate blade 110 is formed to be parallel to the longitudinal direction of the rotary shaft (i.e., the angle formed by the outer surface of the plate blade 110 and the longitudinal direction of the rotary shaft is 0 degree), stirring of the mortar can be performed well, Since the outer surface of the plate blade 110 is formed obliquely by the rotation of the rotating shaft, it is possible to move toward the conveying part while being stirred by the rotation of the rotating shaft.

As the plate blades are rotated by the rotation of the rotary shaft, the plate blades are mixed while pushing the mortar toward the conveyance part. In the stirring blades, the mortar is allowed to pass without being pushed, The mortar is mixed with the mortar pushed by the plate blades in the rear, so that the mixing of the mortar becomes more efficient.

[0030]

The mortar mixed by the mixing unit 100 is conveyed to the discharging unit 300 by the conveying unit 200 because the mixing mortar is sufficiently mixed with the mortar.

The transfer unit 200 has a rotation shaft 10 formed inside the transfer pipe 20 in the same direction as the longitudinal direction of the transfer pipe 20 and the screw 210 surrounds the rotation axis.

The rotary shaft 10 may be formed as a single unit and may be commonly used in the mixing unit 100 and the transfer unit 200. In some cases, the rotary shaft 10 may be separately formed and driven separately in the transfer unit 200. [

The screw 210 is formed in a spiral shape, and is responsible for the transfer of the mortar. In the process of being conveyed by the screw, a certain degree of stirring effect can be obtained.

It is needless to say that the auger type mixer of the continuous mixing type of the present invention can be used not only for mortar but also for continuously mixing and manufacturing concrete.

<Concrete structure repair method>

Hereinafter, a method of repairing a concrete structure using a mortar composition for repairing concrete structures, a coating composition for protecting concrete, and a continuous mixing type auger type mixer will be described below.

First, regular inspection of the existing concrete structure through the safety diagnosis, etc., and the concrete that is deteriorated after the inspection is deteriorated should be removed first. The high-pressure water injection device can remove high-pressure water from the deteriorated portion of the existing concrete structure.

In order to increase the adhesion to the existing section, the chipping process is performed to irregularly rough the surface of the exposed concrete structure before installing the repair mortar. .

After the chipping, foreign matter, old film, deterioration factor existing on the chipping surface of the existing concrete structure are removed and the section is restored by installing repair mortar. Mortar casting can be sprayed like a shock or can be charged depending on the type of concrete structure and the site conditions.

After curing the charged repair mortar, the primer layer is applied, the intermediate layer is applied, and the upper layer is applied.

In the repair process, the repair mortar may use the mortar composition for repairing the concrete structure as described above, and the primer layer, the intermediate layer, and the upper layer may be applied by using the coating composition for concrete protection described above. An auger type mixer of the continuous mixing type as described above can be used.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: rotation shaft 20: conveying pipe
30: motor 40: silo
100: mixing part 200: conveying part
300:
110: plate blade 120:
210: Screw

Claims (11)

delete delete delete delete delete A method for repairing a concrete structure,
a) breaking concrete which is deteriorated in existing concrete structures and which can not be used;
b) chipping step of irregularly smoothing the surface of the exposed existing concrete structure;
c) a surface treatment step for removing foreign matter, old film, and deterioration factor existing on the chipping surface of the existing concrete structure;
d) 25 to 30 parts by weight of one kind of ordinary Portland cement; 7 to 18 parts by weight of a silica sand having an average particle diameter of 0.60 to 0.85 mm; 15 to 25 parts by weight of a silica sand having an average particle diameter of 0.25 to 0.60 mm; 20 to 45 parts by weight of a bottom material having an average particle diameter of 0.25 to 0.85 mm; 8 to 16 parts by weight of pozzolan powder; 3 to 5 parts by weight of calcium sulfoaluminate; 0.2 to 1.2 parts by weight of a fluidizing agent; 1.5 to 4.0 parts by weight of a re-forming type polymer;
e) a curing step of curing the repair mortar;
f) 18 to 35 parts by weight of water; 60 to 80 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; 0.5 to 2 parts by weight of a tackifier; and a primer layer applying a coating composition comprising:
g) applying a mid layer onto the primer layer;
h) applying a top coat layer over the intermediate coat layer,
Wherein the intermediate layer and the top coat layer comprise 5 to 10 parts by weight of water; 0.2 to 2 parts by weight of an additive; 10 to 25 parts by weight of calcium carbonate; 0.1 to 0.8 parts by weight of silica fume; 0.1 to 2 parts by weight of pigment; 5 to 15 parts by weight of titanium dioxide; 40 to 60 parts by weight of an acrylic emulsion resin having a particle size of 100 to 150 nm; 0.5 to 2 parts by weight of silane; From 0.5 to 2 parts by weight of texanol; 0.1 to 0.5 parts by weight of a surfactant; 0.1 to 0.5 parts by weight of an additive; And 0.1 to 1 part by weight of an antifoaming agent. The method according to claim 6,
Wherein the step a) injects the high-pressure water into the deteriorated portion of the existing concrete structure by the high-pressure water injection device
Repair method of concrete structures. delete The method according to claim 6,
The auger type mixer includes a silo 40, a mixing unit 100, a conveying unit 200, and a conveying unit 200. The auger type mixer is a continuously mixing type auger type mixer capable of mixing and transporting the maintenance mortar in the step d) And a discharge unit 300,
The mixing unit 100 includes a rotating shaft 10 formed inside the silo 40; A plate blade 110 fixed to an outer surface of the rotary shaft 10; And an agitating hole (120) formed in the plate blade (110).
Repair method of concrete structures. delete delete

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