KR101952764B1 - Mortar composition for repairing, reinforcing and enhancing earthquake-proof property, and construction method of repair and reinforcement of concrete structure using the same - Google Patents

Abstract

The present invention relates to a repairing and reinforcing mortar composition for improving earthquake-proof performance and a repairing and reinforcing method of a concrete structure using the same. The repairing and reinforcing mortar composition has excellent water repellency and durability. The composition, on the basis of 100 parts by weight of concrete, comprises: 50-250 parts by weight of silica; 1-10 parts by weight of calcium aluminium sulfite; 0.1-8 parts by weight of silica fume; 0.1-10 parts by weight of heat combined ash; 1-10 parts by weight of a polymer; 0.5-5.0 parts by weight of a reinforcing fiber; 1-8 parts by weight of a strength-enhancing agent; 1-10 parts by weight of anhydrous gypsum; 0.5-2.0 parts by weight of a shrinkage reducing agent; 0.1-1.0 part by weight of an antifoaming agent; 1-5 parts by weight of a powdery silicone water repellent; 1-10 parts by weight of a re-emulsified powder resin; 0.1-0.5 parts by weight of a sensitizer; 1-20 parts by weight of silica light hardener having density of 0.2-0.4 g/cm^3 and an average diameter of 0.1-3 mm; 0.1-10 parts by weight of an inorganic curing control agent; 0.1-5 parts by weight of a limestone powder component; and 0.1-2 parts by weight of nano-metal oxide powder.

Description

Mortar composition for repairing, reinforcing and enhancing earthquake-proof property, and construction method of repair and reinforcement of concrete structure using the same}

The present invention relates to the field of construction materials, and more particularly, to a repair method for reinforcing reinforcement of a mortar composition for improving seismic performance and a concrete structure using the same.

In general, concrete structures are deteriorated due to various external factors such as external load, vibration, ultraviolet rays, and rain as time passes, resulting in structural stability problems. The deteriorated concrete structures are repaired by using a repair mortar. And reinforcement.

On the other hand, earthquakes can cause enormous damage in terms of human and property damage among natural disasters, and the shaking of buildings and the collapse of buildings caused by tectonic changes are natural disasters that can cause fear to humans.

For earthquakes, earthquake-resistant design is mainly carried out in countries belonging to earthquake zones such as Japan, whereas in Korea, which is slightly away from earthquake zones, thorough seismic design is not reflected. The situation is overlooked. However, due to the earthquake of magnitude 5.8 in Gyeongju in 2016 and the magnitude 5.6 in Pohang in 2017, Korea is no longer a safe zone for earthquakes. The need for seismic reinforcement for facilities is on the rise.

Since 1996, the seismic standards of buildings have been strengthened, and earthquake-resistant design has been implemented for multi-family houses with more than five stories, and recently, mandatory to apply seismic regulations for all new multi-unit houses.

However, in the case of structures built before the mandatory mandatory seismic design is enforced, seismic design is being reflected through reinforcement work because the seismic design is not reflected. Earthquake-proof reinforcement works are carried out by overlaying high-strength concrete or mortar with seismic performance on it.

In this case, physical properties such as adhesion between concrete (or mortar) having a seismic performance and concrete of an existing structure and compressive strength of a seismic material (concrete or mortar) should be secured. (For example, Republic of Korea Patent Registration No. 10-1655108, 10-1746220, 10-0899843, 10-1419445, etc.)

However, the seismic materials proposed in the existing technologies have insufficient denseness between the compositions, so that the effect of securing adhesion and integrity with the spheres is not sufficient, making it difficult to secure sufficient properties such as adhesion strength, compressive strength, bending strength, and water repellency and water resistance. Because of the insufficient physical properties, the reinforcing effect is difficult to maintain for a long time, and thus there is a need for supplementation. In other words, in the case of the existing repair mortar, the mortar with adhesion strength of 1.0 ~ 2.0 MPa according to the quality standard of KS F 4042 (polymer cement mortar for repairing concrete structures), and lack of durability that causes dropping when applied in the railway site with high vibration. Was exposed. Therefore, there is a great need for improvement.

The present invention has been developed in consideration of the situation of the prior art as described above, in the construction of a concrete structure requiring seismic reinforcement work, excellent water repellency and low absorption rate can be maintained excellent durability, adhesion strength, compressive strength It has excellent physical properties such as strength, flexural strength, etc., and reduces the unit weight of mortar and improves the initial and long-term adhesion performance. It has excellent seismic reinforcement and constructability for concrete structures, and is eco-friendly because it does not use organic solvents. The present invention provides a mortar composition for repair reinforcement and a concrete reinforcement method for a concrete structure using the same, so that the earthquake vibration and various stresses can be uniformly absorbed to enhance the seismic performance of the structure.

The present invention to achieve the above object

50 to 250 parts by weight of silica sand, 1 to 10 parts by weight of calcium alumina sulfite, 0.1 to 8 parts by weight of silica fume, 0.1 to 10 parts by weight of cogeneration ash, 1 to 10 parts by weight of polymer, and 0.5 to 1 part of reinforcing fiber 5.0 parts by weight; 1 to 8 parts by weight strength enhancer; 1 to 10 parts by weight of anhydrous gypsum; Shrinkage reducing agent 0.5-2.0 parts by weight; 0.1 to 1.0 parts by weight of an antifoaming agent; 1 to 5 parts by weight of a powdery silicone water repellent; 1 ~ 10 parts by weight of reemulsified powder resin; 0.1 to 0.5 parts by weight of a reducing agent; 1 to 20 parts by weight of a silica lightweight agent having a density of 0.2 to 0.4 g / cm ³ having an average diameter of 0.1 to 3 mm; 0.1 to 10 parts by weight of the inorganic curing control agent; 0.1 to 5 parts by weight of limestone powder components; And 0.1 to 2 parts by weight of nano metal oxide powder; provides a mortar composition for improving seismic performance.

In one embodiment of the present invention, the cement is characterized in that the cement of one or two or more selected from cement cement, slag cement, alumina cement and cemented carbide.

In addition, in an embodiment of the present invention, the silica sand contains 90 to 99% by weight of particles having a particle size of 0.3 to 3.0 mm and has a Mohs Hardness of 6.0 to 10.0.

In addition, in one embodiment of the present invention, the reinforcing fiber is characterized in that one or more selected from glass fibers, steel fibers, polyester fibers, nylon fibers, polypropylene (PP) fibers, cellulose fibers and polyethylene fibers.

In addition, in one embodiment of the present invention, the first comprising 30 to 40 parts by weight of the cure poultry and 1 to 3 parts by weight of montmorillonite-based clay mineral, 1 to 2 parts by weight of aluminum salt and 50 to 60 parts by weight of water Obtained by mixing the composition with a second composition comprising 5 to 7 parts by weight of a curing accelerator, 12 to 18 parts by weight of clay mineral, 0.1 to 2 parts by weight of nano zinc powder, 0.1 to 0.5 parts by weight of stabilizer, and 60 to 70 parts by weight of water. The seismic performance enhancing agent is characterized in that it further comprises in the range of 5 to 15 parts by weight based on 100 parts by weight of the cement.

At this time, the hardening bale may be formed by mixing the boiler ash 50 to 80% by weight, blast furnace slag powder 10 to 30% by weight and the fastener 3 to 20% by weight.

In addition, the seismic performance enhancing agent may be additionally mixed with 0.1 to 5 parts by weight of a fluidizing agent based on 100 parts by weight of the first composition. In this case, the fluidizing agent may be one or two or more mixed fluidizing agents selected from polycarboxylic acid, melamine and naphthalene-based fluidizing agents.

In addition, the nano metal oxide powder is made of palladium oxide, iridium oxide, ruthenium oxide, osmium oxide, rhodium oxide, platinum oxide, iron oxide, nickel oxide, cobalt oxide, indium oxide, aluminum oxide, titanium oxide, tungsten oxide and magnesium oxide It is characterized by one or two or more mixtures selected from the group.

In this case, the nano metal oxide powder may be a surface coated with graphite oxide.

In addition, the present invention to achieve the above object

A first step of removing and arranging foreign substances on the surface of the concrete structure;

A second step of constructing a penetration-proof protection primer on the surface of the concrete structure from which the foreign substances have been removed; And

A third step of constructing by mixing the water-proof protective primer with a mortar composition for repairing the concrete structure according to the present invention and improving the seismic performance on the surface thereof without curing of the surface;

Provides a repair reinforcement and seismic reinforcement method of the concrete structure comprising a.

In one embodiment of the present invention, after the second step, it may further comprise the step of installing a reinforcing material on the concrete structure in which the penetration-proof protection primer is constructed.

In this case, the reinforcing material may be an elastic wire mesh, an elastic pad or an elastic rod.

In addition, in one embodiment of the present invention, after the third step, it may further comprise the construction of a finish coating material on the surface of the mortar composition for improving the earthquake resistance performance.

Referring to the features and advantages of the repair mortar composition for repair reinforcement for improving the seismic performance according to the present invention and the repair reinforcement method of the concrete structure using the same.

1. First, by including a component having water repellency in the mortar composition to enhance the water repellent effect, lower the water absorption rate to improve durability, it is possible to maintain excellent initial and long term durability, water resistance and weather resistance.

2. By constructing mortar composition using lightweight aggregate to improve the constructability of concrete structures, it is possible to quickly construct even when constructing bridges, buildings, and railway structures to which impact or vibration is applied. Very excellent.

3. In addition, the shrinkage of the composition can be reduced and the strength can be expressed in a short time, and by including reinforcing fibers and powder resin in the mortar composition, the initial and long-term adhesion performance and crack resistance can be improved to further improve long-term durability. There is.

4. In addition, by including the earthquake resistance enhancer, which contains clay minerals, aluminum salts and nano-zinc powder as a base, adhesion and binding strength between components can be strengthened and fine gaps can be filled so that the structure becomes dense, resulting in strength, durability and seismic performance. Physical properties such as can be further improved.

5. Particularly, the railway site or the railway-related concrete structure, where vibrations are severe, can improve the problems of lack of durability, such as mortar dropout, since physical properties such as adhesion strength are enhanced.

1 is a microscope (SEM) photograph showing the interface between the mortar composition obtained in Example 1 and a concrete structure as a base material.

Hereinafter, the present invention will be described in more detail.

As described above, the mortar composition for improving the seismic performance according to the present invention is 50 to 250 parts by weight of silica sand, 1 to 10 parts by weight of calcium alumina sulfite, 0.1 to 8 parts by weight of silica fume, and cogeneration ash 0.1 to 100 parts by weight of cement. 10 parts by weight, 1 to 10 parts by weight of polymer, 0.5 to 5.0 parts by weight of reinforcing fibers; 1 to 8 parts by weight strength enhancer; 1 to 10 parts by weight of anhydrous gypsum; Shrinkage reducing agent 0.5-2.0 parts by weight; 0.1 to 1.0 parts by weight of an antifoaming agent; 1 to 5 parts by weight of a powdery silicone water repellent; 1 ~ 10 parts by weight of reemulsified powder resin; 0.1 to 0.5 parts by weight of a reducing agent; 1 to 20 parts by weight of a silica lightweight agent having a density of 0.2 to 0.4 g / cm ³ having an average diameter of 0.1 to 3 mm; 0.1 to 10 parts by weight of the inorganic curing control agent; 0.1 to 5 parts by weight of limestone powder components; And 0.1 to 2 parts by weight of the nano metal oxide powder.

Hereinafter, each component which comprises the mortar composition for earthquake resistance performance improvement which concerns on the said invention is demonstrated concretely.

First, in the present invention, the cement may use one or two or more mixed cements selected from portland cement, slag cement, alumina cement and cemented carbide, preferably portland cement. In particular, in the case of Portland cement, the main components are C ₃ S 51%, C ₂ S 25%, C ₃ A 9%, C ₄ AF 9%, CaSO ₄ 4%, and the specific surface area is around 3,300 cm ² / g It is preferable to use what is.

When using the mixed cement may include 40 to 70% by weight of portland cement, 20 to 40% by weight of slag cement, 5 to 25% by weight of alumina cement, and the remaining amount of fast-hardening cement.

Among them, the slag cement plays a role in improving the temperature rise due to the heat of hydration due to the stimulating action of calcium hydroxide or sulfate, the suppression of alkali silica reaction, the chemical resistance to sulfate and sea water, and the resistance to chloride ions and oxygen penetration.

In addition, alumina cement is a cement having a relatively higher alumina content than portland cement, which has excellent chemical resistance, can be used in an acidic atmosphere, and has a short hardening time. Used as.

In the present invention, the silica sand contains 90 to 99% by weight of particles having a particle size of 0.3 to 3.0 mm and Mohs Hardness 6.0 or more, preferably 6.0 to 10.0.

In the present invention, the calcium alumina sulfite is mixed with water to hydrate the phenomenon occurs to compensate for the shrinkage of concrete prevents the cracking of the mortar and serves to compact the structure.

In the present invention, the silica fume (Silica fume) is a nearly spherical particles composed of an average particle diameter of about 0.1 ~ 0.5 mm, amorphous silica, and reacts with calcium hydroxide to change to hydrous calcium silicate at room temperature, resulting in superpozzolanic properties.

In the present invention, the reason for adding the silica fume to the mortar composition is to improve the dispersibility and water resistance by the ball bearing effect by the spherical particles and to improve the water-tightness and the high strength by the filling effect of the silica fume between the cement particles, and the shotcrete This is because the adhesion is improved by reducing the amount of ground, suppressing alkali silica reaction, and improving chemical resistance.

In the present invention, the cogeneration ash is a by-product generated in the cogeneration plant, and the cogeneration ash serves to make the internal density of the mortar dense and to strengthen the strength and adhesion performance, and in the present invention, about 0.1 to about 100 parts by weight of cement. It is preferably included in the range of 10 parts by weight.

In the present invention, the polymer serves to improve the physical properties of the mortar by increasing the compatibility and adhesion between the mortar components, polyvinylacetate, polyvinylacetate silane terminated polymer, polyvinyl alcohol, polyvinyl ester silane terminated polymer At least one selected from methyl butyl methacrylate and styrene-butadiene rubber latex, preferably selected from polyvinylacetate, polyvinyl alcohol, butyl methacrylate and styrene-butadiene rubber latex 1 or more types can be used. In the present invention, the amount of the polymer is preferably used in the range of 1 to 10 parts by weight based on 100 parts by weight of the cement.

In the present invention, the reinforcing fiber is effective in the initial construction stability after the mortar, and can be used for the purpose of increasing the initial dispersibility, since it can reduce the surface cracks (cracking) during curing as well as improving the bending strength and tensile strength. In the present invention, the reinforcing fiber is preferably used to have a certain degree of hydrophilic fiber, for example, selected from glass fiber, steel fiber, polyester fiber, nylon fiber, polypropylene (PP) fiber, cellulose fiber and polyethylene fiber It is preferable to use one or more kinds thereof, but is not limited thereto.

In the present invention, the strength enhancer acts to improve concrete properties before and after curing by physical and chemical actions, and specific examples thereof include nitrate salts having alkali metals, nitrate salts having alkaline earth metals, and aluminum. At least one selected from nitrate salts, Al ₂ O ₃ powders, and Al ₂ Si ₂ O ₇ powders may be used.

The anhydrous gypsum in the present invention serves to improve the initial adhesion of the mortar composition to enhance the adhesion strength to the base material.

In the present invention, the shrinkage reducing agent is preferably one having two or more hydroxyl groups having a molecular weight of 100 or more, for example, neopentyl glycol (Neopentyl glycol) may be used. The neopentylglycol has two alcohol groups of symmetry and two methyl groups in the alpha carbon position, thereby showing excellent reactivity to the esterification reaction. In the present invention, the neopentyl glycol may be used in the form of a flake made of 100% of white crystals or a slurry made of 90% of neopentyl glycol and 10% of water.

In the present invention, the antifoaming agent is a component used to remove the large pores in the mortar to improve the strength and appearance of the mortar, and generally a low volatility, high diffusive oily substance or water-soluble surfactant is used, for example kerosene Mineral oil-based antifoaming agents such as liquid paraffin; Oil-based antifoaming agents such as animal and vegetable oils, sesame oil, castor oil and their alkylene oxide adducts; Fatty acid-based antifoaming agents such as oleic acid, stearic acid and alkylene oxide adducts thereof; Fatty acid ester antifoaming agents such as glycerin monolicinolate, alkenyl amber acid fluid, sorbitol monolaurate, sorbitol trioleate, natural wax and the like; Polyoxyalkylenes, (poly) oxyalkyl ethers, acetylene ethers, (poly) oxyalkylene fatty acid esters, (poly) oxyalkylene sorbitan fatty acid esters, (poly) oxyalkylene alkyl (aryl) ethers Oxyalkylene antifoaming agents such as sulfuric acid ester salts, (poly) oxyalkylene alkyl phosphate esters, (poly) oxyalkylene alkylamines, and (poly) oxyalkylene amides; Alcohol antifoaming agents such as octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols, and the like; Amide antifoaming agents such as acrylate polyamine; Phosphate ester defoaming agents such as tributyl phosphate and sodium octyl phosphate; Metal soap-based antifoaming agents such as aluminum stearate and calcium oleate; Silicone antifoaming agents such as dimethylsilicone oil, silicone paste, silicone emulsion, organomodified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil and the like can be used.

In addition, the powder-type silicone water repellent in the present invention serves to improve the water repellency of the mortar composition and to reduce the absorption rate, thereby improving the workability and workability, specifically n-octyltriethoxysilane (n -octyltriethoxysilane).

In the present invention, the re-emulsified powder resin, such as adhesiveness for integration with the concrete structure, water and harmful substances permeation prevention and wear resistance, resistance to bending and impact, imparting viscosity to prevent material separation, such as by filling the voids As a role, EVA (Ethylene vinyl acetate), SBR (Styrene butadienerubber) or acrylic may be used, it is preferably included in the range of about 1 to 10 parts by weight of the composition.

In the present invention, the water reducing agent serves to reduce the water-cement ratio to secure fluidity and prevent durability degradation, and may be used naphthalene-based, melamine-based, sulfonic acid-based, polycarboxylic acid-based water-soluble. The water reducing agent is preferably included in the range of about 0.1 to 0.5 parts by weight in the composition.

In the present invention, the silica lightweight body serves to reduce the density of mortar and at the same time to strengthen the freeze-thaw resistance, in the present invention as having a density of 0.2 ~ 0.4 g / cm ³ having an average diameter of 0.1 ~ 3mm It is preferable to use expanded silica formed in a spherical shape with the inside closed as a light body.

In the present invention, the silica lightweight body is preferably included in the range of about 1 to 10 parts by weight of the total mortar composition.

In the present invention, the inorganic curing control agent achieves integration with the concrete matrix during the construction of the mortar composition and allows the cured body to have high strength, durability and waterproofness, and controls the setting speed to impart fast hardness.

That is, the inorganic curing control agent comprises a binder for strengthening the integrity of the concrete matrix, and a control agent for controlling the setting rate, the binder is composed of CaO and SO ₃ , the control agent is Al ₂ O ₃ and Na ₂ O. Moreover, as for the mixing ratio of the said binder and a control agent, it is more preferable to use what falls in the range of binder / control agent = 1.2-1.8.

In addition, the inorganic curing control agent in the present invention may further comprise a polymer powder resin in addition to the mixture of the binder and the control agent.

The polymer powder resin is a dispersion material prepared by spray drying the liquid resin and is a material that becomes a safe liquid resin when dispersed in water. The powdered resin dispersed in water forms an irreversible polymer film that is insoluble in water after drying, and is mixed with cement like a liquid resin to improve tensile and bending strength. The polymer powder resin may be a natural rubber-based, polyacetate-based resin, it is preferably mixed in about 1 to 10 parts by weight based on 100 parts by weight of the mixture of the binder and the control agent.

The seismic mortar composition of the present invention may further include an earthquake resistance enhancer for improving the seismic performance in the railway field. The seismic performance enhancing agent used in the present invention serves to enhance physical properties such as strength, durability, and seismic performance by strengthening adhesion and binding force between components of the earthquake-resistant mortar composition and filling the microgap to densify the tissue. In the present invention, the seismic performance enhancing agent specifically, the first composition comprising 30 to 40 parts by weight of a hardening current and 1 to 3 parts by weight of montmorillonite-based clay mineral, 1 to 2 parts by weight of aluminum salt and 50 to 60 parts by weight of water. And a second composition comprising 5 to 7 parts by weight of a curing accelerator, 12 to 18 parts by weight of clay mineral, 0.1 to 2 parts by weight of nano zinc powder, 0.1 to 0.5 parts by weight of stabilizer, and 60 to 70 parts by weight of water. do.

In the present invention, the first composition is composed of a cure fertilizer, montmorillon-nirolyl-based clay mineral, aluminum salt and water.

In the present invention, the curing head included in the first composition is formed by mixing 50 to 80% by weight of boiler ash, 10 to 30% by weight of blast furnace slag powder, and 3 to 20% by weight of a fastener.

Here, it is preferable to use an ash (fuel shell of lime or coke) generated in a thermal power plant. The boiler ash is preferably used from the boiler using a circulating fluidized bed combustion boiler that uses bituminous coal and anthracite coal as fuel alone or in combination with one or more.

In addition, the blast furnace slag is preferably used that is ground by a grinding means such as a ball mill or a vibration mill.

In addition, the fastener serves to promote rapid curing (curing) of the earthquake-resistant mortar according to the present invention, the fastener is a solid fastener, for example, sodium carbonate (Na ₂ CO ₃ ), sodium aluminate ( NaAlO ₂ ), calcium hydroxide and sodium silicate (Na ₂ SiO ₃ ) It may include one or more selected, more preferably sodium carbonate, sodium aluminate and sodium silicate in a weight ratio of 1: 1.5 to 2: 0.5 to 1 You can use the included one.

In the present invention, the aluminum salt having the special structure serves to compact the pores in the earthquake-resistant mortar.

In the present invention, the second composition is formed by mixing 5 to 7 parts by weight of a curing accelerator, 12 to 18 parts by weight of clay mineral, 0.1 to 2 parts by weight of nano zinc powder, 0.1 to 0.5 parts by weight of stabilizer, and 60 to 70 parts by weight of water. .

In the present invention, the curing accelerator serves to shorten the curing time to complete the work early, DMA (dimethyl aniline) or Co-octate (cobalt octate) or DMPT (N, N-Dimethyl-p -toluidine) can be used.

In the present invention, the montmorillonite-based clay mineral may be used as the clay mineral.

In the present invention, the nano zinc powder serves to control the curing time and densify the tissue.

In the present invention, as the stabilizer, sodium triphosphate is preferably used so as to lower the viscosity of the second composition and obtain even dispersion and stable homogeneous strength. In addition, sodium carbonate, sodium hexametaphosphate, and sodium silicate are inorganic dispersants. Any one or more of these may be used. The stabilizer also serves to prevent material separation.

At this time, in the present invention, it is preferable to form the first composition and the second composition included in the seismic performance enhancer by mixing in a weight ratio of 5 to 8: 2 to 5, more preferably 7: 3 by weight It is preferred to mix in proportions.

The first composition and the second composition is composed of a two-component type is preferably injected into the mortar immediately before the mortar is poured and mixed.

In addition, the seismic performance enhancing agent in the present invention may further include a fluidizing agent for controlling the fluidity.

The fluidizing agent included in this case is preferably included in the range of about 0.1 to 5 parts by weight based on 100 parts by weight of the first composition.

Examples of preferred fluidizing agents that can be used in the present invention include polycarboxylic acid (PCA-based), melamine-based, naphthalene-based fluidizing agents, and one or a mixture of two or more of the above-mentioned fluidizing agents may be used.

In the present invention, since the limestone powder component may be included in the mortar composition to improve the heat blocking performance, the seismic performance may be further improved along with the fire resistance of the mortar composition.

In the present invention, the nano-metal oxide powder is characterized in that the internal structure is made of porous with a large absorption cross-sectional area, induces light weight in the tissue and serves to compact the tissue.

In the present invention, the nano metal oxide powder is palladium oxide, iridium oxide, ruthenium oxide, osmium oxide, rhodium oxide, platinum oxide, iron oxide, nickel oxide, cobalt oxide, indium oxide, aluminum oxide, titanium oxide, tungsten oxide and oxide One or a mixture of two or more selected from the group consisting of magnesium may be used.

In addition, in the present invention, the nano metal oxide powder may be used in an unprocessed form, but it is preferable to use a coated treatment to prevent fusion with each other in the composition, and specifically, the surface is coated with graphite oxide. It is preferable to use what is used.

In the present invention, the graphite oxide is obtained by treating one or more graphite selected from natural graphite, plate graphite, artificial graphite, expanded graphite, and the like with an oxidizing agent such as sulfuric acid, nitric acid, potassium permanganate, calcium chlorate, and the like. In the method of coating the surface with an oxide, first, the nano metal oxide powder and the graphite oxide are mixed at a predetermined ratio, and a small amount of water is added to form a slurry, followed by irradiation with ultraviolet light so that the graphite oxide is combined with the nano metal oxide powder. A method of forming a coating layer on the surface is used.

As such, the nano metal oxide powder having the coating layer formed on the surface thereof is not easily refused with each other, thereby improving dispersion stability.

The present invention may further include at least one additive selected from 0.1 to 1.0 parts by weight of dispersant, 0.01 to 1.0 parts by weight of retarder, and 0.1 to 1.0 parts by weight of alkali activator, as necessary, in the mortar composition obtained in the composition as described above. have.

The dispersant is adsorbed on the particle surface of the mortar to give a charge to the particle surface to cause mutual reaction between the particles, it is possible to increase the flow by dispersing the aggregated particles to increase the flow due to the water-reducing effect. As the dispersant, a conventional water reducing agent can be used, and for example, a lignin sulfonate, a polynaphthalene sulfonate, a polymelamine sulfonate, or a polycarboxylate water reducing agent can be used alone or in combination of two or more. The content of the dispersant is preferably used 0.1 to 1.0 parts by weight based on 100 parts by weight of the cement.

The retarder may be added for the purpose of securing a workability for a certain period of time by adjusting the hydration rate of the mortar. Examples of retardants include borates such as boric acid and borax, sodium borate, potassium borate, gluconic acid, citric acid, tartaric acid, glucoheptonic acid, arabic acid, malic acid or citric acid, and their sodium, potassium, calcium, magnesium, ammonium and triethanolamine Oxycarboxylic acid, such as inorganic salts or organic salts, such as these; Monosaccharides such as glucose, fructose, galactose, saccharose, xylose, abitose, lipoose and isosaccharides, oligosaccharides such as disaccharides and trisaccharides, oligosaccharides such as dextrins, and polysaccharides such as dextran, Sugars such as molasses containing these; Sugar alcohols such as sorbitol; Magnesium silicate; Phosphoric acid and its salts or boric acid esters; Aminocarboxylic acids and salts thereof; Alkali soluble protein; Fuminic acid; Tannic acid; phenol; Polyhydric alcohols such as glycerin; Aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and alkali metal salts thereof, alkali Phosphonic acids such as earth metal salts and derivatives thereof. The content is preferably added 0.01 to 1.0 parts by weight based on 100 parts by weight of the cement.

The alkali activator is a component that affects the strength development, it is possible to use one or two or more mixtures selected from alkali metal hydroxides, chlorides, sulfur oxides and carbonates, preferably using sodium carbonate and sodium hydrogen carbonate It is advantageous in terms of strength development. In the present invention, the content of the alkali activator is preferably added 0.1 to 1.0 parts by weight based on 100 parts by weight of the cement.

In addition, the mortar composition according to the present invention may further include a water-insoluble agent in the range of 0.1 to 3 parts by weight for maintenance reinforcement of the underwater concrete structure. The water-insoluble agent is added in order to improve the viscosity of the mortar composition in water to prevent degradation, methyl-based cellulose such as methyl cellulose, hydroxymethyl cellulose, carboxymethyl cellulose; Ethyl cellulose such as ethyl cellulose, hydroxyethyl cellulose and carboxyethyl cellulose; Cellulose thickeners selected from propyl celluloses such as hydroxypropyl cellulose can be used. The content is preferably included in 0.1 to 3 parts by weight based on 100 parts by weight of the cement because it exhibits the appropriate viscosity. If necessary, in order to further increase the viscosity in water, water-soluble acrylic resin powder may be further added, and the water-soluble acrylic resin powder is preferably used in an amount of 1 to 30% by weight of the water-insoluble agent.

Using the mortar composition according to the present invention obtained as described above can be carried out repair reinforcement and seismic reinforcement construction of the concrete structure. Hereinafter will be described in detail with respect to the repair and reinforcement construction method of the concrete structure.

First, when the concrete is cracked in the concrete structure due to deterioration, and the time passes, the compressive strength of the concrete and the tensile strength of the reinforcing bar gradually decreases, and the concrete exposed to the cracking site is neutralized to cause corrosion of the rebar. If such a phenomenon occurs by the diagnosis and inspection of the structure, reinforcement of the concrete structure can maintain the life of the building for a long time.

Remove debris, grease, latencies, etc. from the deteriorated concrete structure or concrete structure requiring seismic reinforcement, and then remove the cracked concrete and exposed reinforcing bars to cut the machine until the deteriorated concrete comes out. Shred and trim.

Specifically, the neutralization depth is measured using a phenolphthalein solution while chipping the deteriorated concrete section or surface by checking the cross section or surface condition of the concrete structure to be constructed before performing the repair reinforcement and seismic reinforcement method of the concrete structure. Thereafter, the concrete cross section or surface from which deterioration is advanced by the neutralization reaction is removed.

Subsequently, the part where the concrete is removed is ground to proceed with the surface work and washed with high pressure water. The process of washing using an air compressor before the high pressure water operation may be further provided.

Subsequently, after the surface cleanup as described above, the waterproofing protective layer is coated on the surface of the concrete structure from which the foreign matter is removed to form a waterproof layer.

In other words, check the condition of the rebar, if the corrosion of the reinforcement is severe, take out the back of the reinforcement, remove the corrosion (rust) by using an iron brush or grinder in the areas of high corrosion and apply a waterproofing protective primer primer. In the present invention, it is preferable to use an amine primer such as carboxylamine as the penetration waterproofing protective primer, but is not limited thereto.

Then, optionally, the reinforcement may be installed in the concrete structure in which the penetration waterproof protective primer is constructed.

The reinforcement is a process of installing the anchor reinforcement by cutting the reinforcing bar and inserting new reinforcing bars, carbon rods, rods, etc. when the structural function as a rebar is lost because the degree of corrosion is very severe. Elastic wire mesh, elastic pads, elastic rods and the like are preferred.

In this case, the reinforcing material is more preferable because when the surface treated by using a montmorillonite-based clay mineral to the surface treatment, the bonding force with the seismic mortar is subsequently applied and may be integrated.

Subsequently, the primer is applied and cured to spray and apply the mortar composition for improving seismic performance according to the present invention using a mechanical spraying device to a concrete structure in the absence of surface tackiness (or the reinforcement is installed). .

As the mechanical spraying device which can be used in the present invention, it is preferable to use an integrated mortar spraying device in which a mixing device, a discharge device, a generator, and a compressor are combined or mounted.

In the present invention, by applying the mortar composition for earthquake resistance improvement according to the present invention obtained on the construction target surface to repair and reinforce the concrete structure, when repeated one or more times, the surface is polished for adhesion to the target surface The coating is roughly finished, and the coating is preferably applied and plastered by spraying or trowel with 5 to 15 mm in the first place, 20 to 50 mm in the second place and the third place, and 5 to 15 mm when the final place. The thickness can be changed depending on the thickness of the chipped concrete.

In this way, the repair construction can be completed by curing the mortar composition for seismic performance improvement placed on the concrete structure.

On the other hand, in the present invention, after repair reinforcement and seismic reinforcement construction of the concrete structure, in order to improve the durability and life of the reinforcement performance can be further coated by coating the coating.

In the present invention, the finish coating material may be an acrylic-urethane copolymer coating material, but is not limited thereto. The coating of the finish coating material in the present invention is preferably carried out after about one week after the application of the mortar composition for improving the seismic performance.

In the present invention, the acrylic-urethane copolymer system finish coating material is very excellent in weather resistance, surface strength and water resistance reinforcement effect. In the present invention, the finish coating material is applied to 20 ~ 200g / m ² and the coating thickness is preferably applied to a thickness of 50 ~ 300㎛ in the step before drying.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of the present invention is not limited by the following examples.

EXAMPLE

Preparation Example 1 Preparation of Mortar Composition

100 parts by weight of Portland cement, 150 parts by weight of silica sand (0.3-3.0 mm, hardness 6 or more), 5 parts by weight of calcium alumina sulfite, 5 parts by weight of polyvinylacetate polymer, 5.0 parts by weight of silica fume, a mixture of glass fiber and steel fiber 1.0 parts by weight, nitrate salt strength enhancer 5 parts by weight, anhydrous gypsum 5.0 parts by weight, neopentyl glycol shrinkage reducing agent 1.0 parts by weight, antifoaming agent 0.3 parts by weight, n-octyltriethoxysilane powder type silicone waterproofing agent 2.5 parts by weight, water reducing agent 0.2 parts by weight, 5 parts by weight of silica lightweight agent having a density of 0.2 to 0.4 g / cm ³ having an average diameter of 0.1 to 3 mm, 0.8 parts by weight of inorganic curing control agent, 0.5 parts by weight of limestone powder component and a mixture of iron oxide and cobalt oxide 1.0 parts by weight of the nano metal oxide powder was uniformly mixed with an appropriate amount of water to prepare a mortar composition. In this case, the inorganic curing control agent comprises a binder made of CaO and SO ₃ and a control agent made of a mixture of Al ₂ O ₃ and Na ₂ O as a control agent for controlling the setting rate of the binder, the binder and The mixing ratio of the control agent was used in such a manner that the binder (CaO + SO ₃ ) / control agent (Al ₂ O ₃ + Na ₂ O) = 1.5.

Preparation Example 2 Preparation of Mortar Composition

A mortar composition was prepared in the same manner as in Preparation Example 1, except that the first mortar composition contained 35 parts by weight of a cured presenter, 2 parts by weight of montmorillonite-based clay mineral, 1.5 parts by weight of aluminum salt, and 61.5 parts by weight of water. And a second composition including 6 parts by weight of a curing accelerator, 15 parts by weight of clay mineral, 0.5 part by weight of nano zinc powder, 0.5 part by weight of a stabilizer, and 65 parts by weight of water, and then, mixed with each other at a weight ratio of 7: 3. The mortar composition was obtained by uniformly mixing about 10 parts by weight of the obtained composition as an earthquake-resistant enhancer with an appropriate amount of water.

Comparative Preparation Example 1 Preparation of Mortar Composition

The mortar composition was prepared by mixing 55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyung Mining Co.), and an appropriate amount of water, with 100 parts by weight of the cement binder having an average particle diameter of 0.1 to 1.0 mm.

Comparative Preparation Example 2 Preparation of Mortar Composition

100 parts by weight of Portland cement, blast furnace quenching slag and blast furnace slow cooling slag were mixed in a weight ratio of 5: 5, and 20 parts by weight of synthetic slag fine powder having an average particle diameter of 2 to 10 µm, 1.0 part by weight of polymer resin (EVA resin), cellulose fiber A mortar composition was prepared by mixing 1.0 parts by weight and 0.5 parts by weight of sodium hydrogen carbonate, and 55 parts by weight of silica sand composed of fine sand having an average particle diameter of 0.1 to 1.0 mm, 9.5 parts by weight of limestone (Gyeong Mining), and an appropriate amount of water. .

Comparative Preparation Example 3 Preparation of Mortar Composition

65 parts by weight of Portland cement, blast furnace quenching slag and blast furnace slow cooling slag were mixed at a weight ratio of 5: 5, and 20 parts by weight of fine powder of synthetic slag having an average particle diameter of 2 to 10 µm, 1.0 part by weight of polymer resin (EVA resin), cellulose fiber 1.0 parts by weight and 0.5 parts by weight of sodium bicarbonate, 0.5 parts by weight of water-insoluble agent (methylcellulose), 0.5 parts by weight of dispersant (PC-based), 0.2 parts by weight of antifoaming agent, and 0.05 parts by weight of retardant (tartaric acid) were added and mixed. To prepare a mortar composition, 55 parts by weight of silica sand consisting of fine sand having an average particle diameter of 0.1 to 1.0 mm, 9.5 parts by weight of limestone (Gyeonggi Mining), and an appropriate amount of water were mixed.

Example 1

The surface of the damaged concrete structure was chipped, crushed and ground to clean the surface, and the surface was cleaned using a high pressure cleaner. Thereafter, the amine-based penetration waterproofing protective primer was applied to the exposed reinforcing bars, and the mortar composition prepared in Preparation Example 1 was applied while the primer was cured and there was no surface tagging. Dry curing for the day to complete the reinforcement construction.

Example 2

The surface of the damaged concrete structure was chipped, crushed and ground to clean the surface, and the surface was cleaned using a high pressure cleaner. Thereafter, the amine-based penetration waterproofing protective primer was applied to the exposed reinforcing bar, and the mortar composition prepared in Preparation Example 2 was applied while the primer was cured and there was no surface tagging. Dry curing for the day to complete the reinforcement construction.

Example 3

The surface of the damaged concrete structure was chipped, crushed and ground to clean the surface, and the surface was cleaned using a high pressure cleaner. Thereafter, the amine-based penetration waterproofing protective primer was applied to the exposed reinforcing bars, and the mortar composition prepared in Preparation Example 1 was applied while the primer was cured and there was no surface tagging. Dry curing for the day to complete the reinforcement construction. The dried and cured mortar surface was coated twice with a 100 μm thick finish coating material, then cured and dried to finish the reinforcement construction.

Example 4

The surface of the damaged concrete structure was chipped, crushed and ground to clean the surface, and the surface was cleaned using a high pressure cleaner. Thereafter, the amine-based penetration waterproofing protective primer was applied to the exposed reinforcing bar, and the mortar composition prepared in Preparation Example 2 was applied while the primer was cured and there was no surface tagging. Dry curing for the day to complete the reinforcement construction. The dried and cured mortar surface was coated twice with a 100 μm thick finish coating material, then cured and dried to finish the reinforcement construction.

Comparative Example 1

The same process as in Example 1, except that the reinforcement of the concrete structure using the mortar composition prepared in Comparative Preparation Example 1 was carried out differently.

Comparative Example 2

The same process as in Example 1, except that the reinforcement of the concrete structure using the mortar composition prepared in Comparative Preparation Example 2 was carried out differently.

Comparative Example 3

The same process as in Example 1, except that the reinforcement of the concrete structure using the mortar composition prepared in Comparative Preparation Example 3 was carried out differently.

Performance evaluation

(1) Physical properties of mortar composition

Test specimens were prepared using the mortars prepared in Preparation Examples and Comparative Preparation Examples, and physical properties were measured by the following test methods.

1) Absorption rate, flow, slurry density: conducted in accordance with KS L 5220

2) Flexural strength: KS F 2476 "Method of testing the strength of polymer cement mortar"

3) Compressive strength: KSF 2405

4) Bonding strength: KS F 4716 `` Strength Test Method of Polymer Cement Mortar ''

5) Length change rate: Measured according to the test method for changing the length of mortar and concrete KS F 2424. The value is 0 for the initial construction body, "-" represents the shrinkage rate, and "+" represents the expansion rate.

The results are shown in Table 1 below.

Item Preparation Example 1 Preparation Example 2 Comparative Production Example 1 Comparative Production Example 2 Comparative Production Example 3 Absorption rate (%) 9 10 25 28 31 Flow (mm) 125 129 120 119 120 Slurry density 1.60 1.57 1.90 1.96 2.01 Flexural strength
(N / mm ² ) 7 days 8.9 8.5 6.9 6.7 6.5 28 days 11.2 10.9 8.0 8.9 8.5 Compressive strength
(N / mm ² ) 1 day 15.2 14.2 11.0 11.0 12.0 3 days 26.5 26.7 15.5 11.2 12.0 7 days 37.8 36.8 34.0 35.1 35.1 28 days 47.5 47.2 41.0 40.1 42.0 Adhesion strength
(N / mm ² ) Standard condition 3.8 3.9 1.2 1.3 1.4 After repeated hot and cold 3.5 3.4 1.4 1.3 1.5 Change of length
rate(%) 3 days 0.013 0.017 0.045 0.046 0.039 7 days 0.004 0.005 0.006 0.005 0.004 14 days -0.01 -0.02 -0.05 -0.05 -0.04 28 days -0.024 -0.024 -0.06 -0.055 -0.04

As shown in Table 1, in the case of the mortar composition for improving the seismic performance according to the present invention, it can be confirmed that physical properties such as compressive strength and adhesion strength are remarkably superior to the conventional mortar composition.

(2) Seismic retrofit and section recovery performance evaluation

1) Weatherability Assessment

400 hours were measured according to ASTM G 155.

2) surface hardness evaluation

Pencil hardness was measured according to KS D 6711.

3) Water resistance evaluation

The time at which surface deformation (cracks, blisters, etc.) occur continuously at 90 ° C. hot water was measured.

The evaluation results are shown in Table 2.

Weather resistance (white) Surface hardness Water resistance Example 1 △ E0.9 6H 580 hr Example 2 △ E0.8 6H 590 hr Example 3 △ E1.1 6H 610 hr Example 4 △ E1.1 5H 620hr Comparative Example 1 △ E3.1 3H 350 hr Comparative Example 2 △ E3.4 4H 340hr Comparative Example 3 △ E3.2 3H 330hr

As shown in Table 2, when the concrete structure using the mortar composition for improving the seismic performance according to the present invention and reinforce the concrete structure and selectively apply a finish coating material on the surface of the case using a conventional mortar composition and using a conventional coating agent It can be seen that weather resistance, surface hardness and water resistance are remarkably excellent as compared with the above.

From the results of Table 1 and Table 2, the mortar composition for improving the seismic performance according to the present invention is excellent in physical performance of the mortar, excellent adhesion to concrete, and also excellent in physical properties such as weather resistance and water resistance, thereby improving the reinforcing effect of the concrete structure. It can be confirmed that it can be maintained for a long time and can also be advantageous to exhibit seismic performance.

(3) Interface shape between concrete and mortar

The interface between the mortar composition obtained in Example 1 and the base concrete structure using a microscope (SEM) was photographed and shown in FIG. 1.

As shown in the drawings, the mortar composition according to the present invention forms a polymer film and a bridge at the interface with the concrete, and thus, it is expected that high-quality repair work is possible because of excellent adhesive strength and initial adhesive strength.

The present invention is not limited to the above-described specific embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the present invention described in the claims. Such changes should, however, be construed as falling within the scope of the appended claims.

Claims (14)

50 to 250 parts by weight of silica sand, 1 to 10 parts by weight of calcium alumina sulfite, 0.1 to 8 parts by weight of silica fume, 0.1 to 10 parts by weight of cogeneration ash, 1 to 10 parts by weight of polymer, and 0.5 to 1 part of reinforcing fiber 5.0 parts by weight; 1 to 8 parts by weight strength enhancer; 1 to 10 parts by weight of anhydrous gypsum; Shrinkage reducing agent 0.5-2.0 parts by weight; 0.1 to 1.0 parts by weight of an antifoaming agent; 1 to 5 parts by weight of a powdery silicone water repellent; 1 ~ 10 parts by weight of reemulsified powder resin; 0.1 to 0.5 parts by weight of a reducing agent; 1 to 20 parts by weight of a silica lightweight agent having a density of 0.2 to 0.4 g / cm ³ having an average diameter of 0.1 to 3 mm; 0.1 to 10 parts by weight of the inorganic curing control agent; 0.1 to 5 parts by weight of limestone powder components; And 0.1 to 2 parts by weight of the nano metal oxide powder;
The nano metal oxide powder is characterized in that the internal structure is made of porosity to induce light weight in the tissue and densify the tissue,
The nano metal oxide powder is in the group consisting of palladium oxide, iridium oxide, ruthenium oxide, osmium oxide, rhodium oxide, platinum oxide, iron oxide, nickel oxide, cobalt oxide, indium oxide, aluminum oxide, titanium oxide, tungsten oxide and magnesium oxide. One or more selected mixtures characterized in that the surface is coated with graphite oxide,
The graphite oxide is a treatment of sulfuric acid, nitric acid, potassium permanganate or calcium chlorine with at least one graphite selected from natural graphite, plate graphite, artificial graphite and expanded graphite, and the nano metal oxide powder and graphite oxide are mixed at a predetermined ratio. It is formed by adding water to form a slurry and then irradiated with ultraviolet light so that the graphite oxide is combined with the nano-metal oxide powder to form a coating layer on the surface, characterized in that the nano-metal with a graphite oxide coating layer formed on the surface An oxide powder is a mortar composition for improving seismic performance, characterized in that to prevent mutual refusion to improve dispersion stability.
The method according to claim 1,
The cement is a mortar composition for improving seismic performance, characterized in that the cement of one or two or more selected from cement, slag cement, alumina cement and cemented carbide cement.
The method according to claim 1,
The silica sand containing 90 to 99% by weight of particles having a particle size of 0.3 ~ 3.0 mm and the Mohs Hardness (Mohs Hardness) 6.0 ~ 10.0 characterized in that the mortar composition for improving the performance.
The method according to claim 1,
The reinforcing fiber is a mortar composition for improving seismic performance, characterized in that at least one selected from glass fibers, steel fibers, polyester fibers, nylon fibers, polypropylene (PP) fibers, cellulose fibers and polyethylene fibers.
The method according to claim 1,
First composition comprising 30 to 40 parts by weight of the present cure present, 1 to 3 parts by weight of montmorillonite clay mineral, 1 to 2 parts by weight of aluminum salt and 50 to 60 parts by weight of water, 5 to 7 parts by weight of curing accelerator, Earthquake-resistant performance enhancer obtained by mixing 12 to 18 parts by weight of clay mineral, 0.1 to 2 parts by weight of nano zinc powder, 0.1 to 0.5 part by weight of stabilizer and 60 to 70 parts by weight of water, is based on 100 parts by weight of the cement. A mortar composition for improving seismic performance, characterized in that it further comprises in the range of 5 to 15 parts by weight.
The method according to claim 5,
The cured poultry is 50 to 80% by weight of the boiler ash, blast furnace slag powder 10 to 30% by weight and 3 to 20% by weight of the fastener formed mortar composition for improving seismic performance.
The method according to claim 5,
The seismic performance enhancing agent is a mortar composition for improving seismic performance, characterized in that 0.1 to 5 parts by weight of the fluidizing agent is further added based on 100 parts by weight of the first composition.
The method according to claim 7,
The fluidizing agent is a mortar composition for improving seismic performance, characterized in that one or two or more mixed fluidizing agents selected from polycarboxylic acid, melamine-based and naphthalene-based fluidizing agents.
delete delete A first step of removing and arranging foreign substances on the surface of the concrete structure;
A second step of constructing a penetration-proof protection primer on the surface of the concrete structure from which the foreign substances have been removed; And
A third step of constructing the waterproofing protective primer by mixing the water with a mortar composition for reinforcing the concrete structure according to claim 1 and improving the seismic performance in a state in which there is no surface tack on the surface;
Repair reinforcement and seismic reinforcement method of concrete structures, including.
12. The method of claim 11, further comprising, after the second step, installing a reinforcing material on the concrete structure in which the penetration waterproofing protection primer is constructed.
The method of claim 12, wherein the reinforcing material is an elastic wire mesh, elastic pad or elastic rod repair and reinforcement method of the concrete structure, characterized in that.
12. The method of claim 11, after the third step, repair and reinforcement of the concrete structure further comprising the construction of the finishing coating material on the surface of the repaired concrete structure and the mortar composition for improving the seismic performance performance Method.

Images