KR102162041B1 - Eco-friendly mortar composition with improved durability and chemical resistance for repairment and reinforcement of structure and method of repairing and reinforcing structure using the same - Google Patents

Abstract

The present invention relates to an eco-friendly mortar composition for repairing and reinforcing a structure with excellent durability and chemical resistance, and a method of repairing and reinforcing a structure by using the eco-friendly mortar composition, and more particularly, the present invention provides a mortar composition for repair and reinforcement and a method of repairing and reinforcing a concrete structure by applying the mortar composition, which is easily installed on a surface or a section of the concrete structure by a repair work, has excellent adhesion and durability as well as fire resistance and chemical resistance so as to be suitable for a repair work in harsh environments, and has a low rebound and excellent physical properties such as compressive strength and bending strength.

Description

Eco-friendly mortar composition with improved durability and chemical resistance for repairment and reinforcement of structure and method of repairing and reinforcing structure using the same}

The present invention relates to a method for producing a chemical-resistant and fire-resistant mortar composition, a chemical-resistant and fire-resistant mortar composition prepared by the above method, and a fire-repair repair construction method of a concrete structure using the same, and specifically, to salt damage or neutralization and chemical conditions. The present invention relates to a mortar composition for repairing and reinforcing structures having strong resistance to resistance and excellent durability and fire resistance, and a method of repairing and reinforcing concrete structures using the same.

After construction, reinforced concrete structures deteriorate due to salt damage, neutralization, alkali aggregate reaction, chemical corrosion, and corrosion expansion of steel due to penetration of water, resulting in deterioration in durability and usability in the long term. If the deterioration of the structure continues, there is a risk of eventually causing the structure to collapse, so it is necessary to continuously manage and repair it.

Since delamination of the surface of the structure or the occurrence of initial defects or cracks facilitates the movement of deterioration factors and promotes the progress of deterioration, in order to secure the stability and performance of the reinforced concrete structure, repair and reinforcement is carried out at the beginning of deterioration to prevent further deterioration. It is necessary to suppress and improve the durability performance.

Therefore, after removing the concrete part containing deterioration factors such as peeling or dropping of the structure section due to deterioration of concrete, corrosion of steel, or other causes, fill or spray the section repair material to restore the section to its original performance and shape. It is common to perform repairs through construction.

Conventional repair stiffeners for cross-section restoration are mainly cement-based mortar or polymer cement mortar. These conventional repair stiffeners have the purpose of suppressing the deterioration of the existing structure and improving the durability performance beyond the present. Since most of them focus only on improving the adhesion performance during construction, the surface is easily damaged again shortly after construction, so there is a problem that frequent repair and reinforcement work is required.

For example, Korean Patent Application Publication No. 2006-0079447 proposes a method of preparing a mortar composition by adding calcium sulfoaluminate (CSA) and a predetermined high-fine powder binder. However, since the mortar composition prepared using the above material uses expensive Hayne-based cement, it induces an increase in the construction cost and did not obtain sufficient results in terms of initial setting time and strength.

In addition, in the case of construction using the existing repair and reinforcement method, since moisture and oxygen permeate into the fine gaps from the surface, the corrosion of the reinforcing bar by oxygen proceeds, and the deterioration of the concrete by moisture occurs, making it difficult to sustain the repair and reinforcement effect for a long time. Therefore, there was a problem that the repair and reinforcement work had to be performed frequently.

As a related technology, Korean Patent Registration No. 10-0582840 provides a high toughness and high fire resistance mortar composition by mixing polymer cement mortar, short fibers, fireproof powder and water at a certain ratio, thereby improving the durability performance of construction and civil structures. It proposes a high toughness, high fire resistance mixed mortar composition capable of simultaneously improving fire resistance performance such as heat shielding property by fire and explosive heat resistance.

In addition, Republic of Korea Patent No. 10-0659458 is a mixture of polypropylene powder, glass beads, resin beads, etc. in dry mortar consisting of admixtures composed of cement, blast furnace slag powder, limestone fine powder, fine aggregates, expanding agent, and shrinkage reducing agent. We propose a technology to exhibit fireproof heat shielding performance by self-filling by injecting and hardening a fireproof filled mortar prepared by mixing a heat absorbing material, organic fiber, water reducing agent, and blending water into the space formed between the surface of the concrete member and the finished panel.

In addition, Korean Patent Registration No. 10-1117634 discloses a binder containing cement, slag, and an expanding agent, and an inorganic salt-based additive containing silica fine powder, silicide, potassium sulfate, EVA resin, an auxiliary agent containing PP resin, and a melamine-based fluidizing agent. As a refractory mortar composition comprising an admixture including a thickener and an aggregate, it is possible to exhibit stable fire resistance performance by adding the inorganic salt-based additive, has excellent compressive strength and durability, and proposes a technology that improves resistance to high temperatures. do.

In addition, Korean Patent Registration No. 10-1016156 treats a fire-resistant mortar composed of a binder, fiber, melamine-based fluidizing agent, and aggregate on the surface of a concrete structure, but increases the amount of fiber added to give excellent strength and improve fire resistance and heat insulation. We propose a technology about the fireproofing method of concrete structures.

As described above, most of the conventional technologies claim to have an effect of improving insulation performance and durability by adjusting the ratio of some of the concrete compositions or adding materials, but it is understood that the degree of improvement is not large.

On the other hand, for maintenance and reinforcement of sewer structures subjected to chemical erosion due to sulfuric acid, structures in a salt-damaged environment, various polluted facilities, and general concrete structures, it is necessary to carry out repair work using mortar, which is endowed with chemical resistance, especially acid resistance. There is a need.

In the case of polymer mortar, which is a major constituent material of portland cement or polymer, which is currently commonly used, there is a problem that it is poor in an environment where chemical corrosion occurs strongly despite its excellent physical properties.

In the case of research on most of the conventional mortar compositions for repair, research and development for technology to increase chemical resistance in poor environments was sluggish.

The present invention has been developed to overcome the problems and limitations of the prior art as described above, and has excellent adhesion and durability, as well as fire resistance and chemical resistance that can be simply installed on the surface or section of a concrete structure by repair construction. It is intended to provide a mortar composition for repair and reinforcement that is suitable for repair construction in the environment, has little rebound amount, and has excellent properties such as compressive strength and flexural strength, and a technology to repair and reinforce concrete structures by applying it.

In order to achieve the above object, the present invention

(1) chipping the cross section of the concrete structure that needs to be repaired to trim until an undamaged part comes out;

(2) applying a primer containing cement, admixture, liquid sodium silicate, liquid polysilane, and water to the polished concrete cross section;

(3) Cement 30-75% by weight, blast furnace quenching slag, and blast furnace slow cooling slag are included in a weight ratio of 7 to 9: 1 to 3 on the surface of the cross section to which the primer is applied, and the powder is 1,000 to 5,000 cm ² /g. Synthetic slag fine powder mixture 5~45% by weight, 5~30% by weight of glass powder having a powderiness of 1,000~3,000 cm ² /g, 3~20% by weight of shrinkage reducing agent, 0.5~1.5% by weight of polymer resin, 0.2~2 fiber Wt%, silica fume 1 to 5 wt%, clinker 0.5 to 5.0 wt%, plaster 0.5 to 5.0 wt%, alpha-type hemihydrate gypsum 0.5 to 5 wt%, fly ash 0.01 to 5 wt%, red mud 0.1 to 5 wt% , Comprising comprising 100 parts by weight of a binder consisting of 0.01 to 5% by weight of calcined fozolana, 0.01 to 5% by weight of microsilica and 20 to 100 parts by weight of silica sand and water,

The synthetic slag fine powder mixture is a mechanochemical-activated mixture in which a mixture obtained by mixing and pulverizing a plastic composite and a polypropylene porous granular material additionally in the process of finely powdering the blast furnace quenching slag and the blast furnace slow cooling slag in a vibration mill. Applying the mortar composition; And

(3) A water-based epoxy-based paint comprising an epoxy main material, an amine-based curing agent, and water is applied to the surface to which the mortar composition is applied, and a water-dispersible acrylic urethane resin, an extender pigment, and Applying a surface coating agent by applying an aqueous urethane-based paint comprising silane; It provides an eco-friendly repair and reinforcement method of the section of the concrete structure including.

In an embodiment of the present invention, the polymer resin in (3) is ethylene vinyl acetate (EVA), NR (Natural Rubber), NBR (Natural Rubber-Butadien Rubber), SBR (Styrene). -Butadien Rubber) and polyvinyl acetate (Polyvinyl Acetate) using any one or a mixture of two or more selected from resins, the fibers are polypropylene fibers 20-50% by weight, nylon fibers 20-50% by weight, and arbocell It is characterized in that it comprises 30 to 60% by weight of fibers.

In addition, in an embodiment of the present invention, the plastic composite in (3) is an aluminum epoxy nanocomposite.

In addition, in an embodiment of the present invention, the porous polypropylene granular material in (3) is characterized in that it is a porous granular material composed of a polypropylene resin, carbon fiber, and flame retardant.

In addition, in an embodiment of the present invention, the synthetic slag fine powder mixture in (3) is 100 parts by weight of a mixture of the blast furnace quenching slag and the blast furnace slow cooling slag, 0.1 to 10 parts by weight of a plastic composite, and 0.1 to a polypropylene porous granular material. It characterized in that it is configured by mixing ~3.0 parts by weight.

The concrete structure repair and reinforcement method according to the present invention has the following advantages.

First, by using blast furnace slag powder and fly ash, active silicon dioxide (SiO ₂ ), which is a reactive active ingredient of the material, exhibits strong properties against chemical corrosion that may be caused by harmful gases, particularly sulfuric acid gas.

In addition, by using a plastic composite made of an aluminum epoxy nanocomposite, the sintering of the mortar is accelerated, thereby increasing the sintering strength and improving the livestock properties.

In addition, the use of porous polypropylene granules enhances the compactness of the cured structure, prevents temperature cracking due to heat of hydration, and contains blast furnace slag, red mud, calcined solana, and microsilica in the slag-containing mixture included in the binder. If a finely powdered mixture is used, physical strength such as the compressive strength of the repair and reinforcement surface is reinforced, and durability and water resistance are improved by reinforcing the adhesive strength with the concrete surface, thereby maintaining the repair and reinforcement effect for a long time.

In addition, physical strength such as compressive strength, flexural strength, and tensile strength of the repair and reinforcement surface is reinforced, and the adhesion strength with the concrete surface is enhanced to improve durability and water resistance, excellent chemical resistance and water resistance, and are resistant to fusion and salt damage. It has excellent resistance to.

In addition, the coating composition used as a surface coating is excellent in durability, and in particular, has excellent properties such as chemical resistance, water resistance, and salt resistance, and has a self-defense function, so it has excellent surface reinforcement effect of concrete structures, and organic solvents or heavy metals are eluted. As it is not, it is eco-friendly, and since the life of the coating film can be extended, the reinforcing effect of the concrete surface can be maintained for a long time.

In addition, since mortar with industrial by-products as the main raw material is used, it is possible to reduce cost by reducing raw material costs, and it is an environmentally friendly method because it can reduce the treatment cost of industrial waste and can be used as a new application.

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

As described above, the concrete structure repair and reinforcement method according to the present invention includes the following steps. In other words,

(1) chipping the cross section of the concrete structure that needs to be repaired to trim until an undamaged part comes out;

(2) applying a primer containing cement, admixture, liquid sodium silicate, liquid polysilane, and water to the polished concrete cross section;

(3) Cement 30-75% by weight, blast furnace quenching slag, and blast furnace slow cooling slag are included in a weight ratio of 7 to 9: 1 to 3 on the surface of the cross section to which the primer is applied, and the powder is 1,000 to 5,000 cm ² /g. Synthetic slag fine powder mixture 5~45% by weight, 5~30% by weight of glass powder having a powderiness of 1,000~3,000 cm ² /g, 3~20% by weight of shrinkage reducing agent, 0.5~1.5% by weight of polymer resin, 0.2~2 fiber Wt%, silica fume 1 to 5 wt%, clinker 0.5 to 5.0 wt%, plaster 0.5 to 5.0 wt%, alpha-type hemihydrate gypsum 0.5 to 5 wt%, fly ash 0.01 to 5 wt%, red mud 0.1 to 5 wt% , Comprising comprising 100 parts by weight of a binder consisting of 0.01 to 5% by weight of calcined fozolana, 0.01 to 5% by weight of microsilica and 20 to 100 parts by weight of silica sand and water,

The synthetic slag fine powder mixture is a mechanochemical-activated mixture in which a mixture obtained by mixing and pulverizing a plastic composite and a polypropylene porous granular material additionally in the process of finely powdering the blast furnace quenching slag and the blast furnace slow cooling slag in a vibration mill. Applying the mortar composition; And

(3) A water-based epoxy-based paint comprising an epoxy main material, an amine-based curing agent, and water is applied to the surface to which the mortar composition is applied, and a water-dispersible acrylic urethane resin, an extender pigment, and Applying a surface coating agent by applying an aqueous urethane-based paint comprising silane; Consists of including.

Hereinafter, each step will be described in detail.

1. Cross section chipping of concrete structures

In concrete structures, cracks occur in the concrete due to deterioration, and as time passes, the compressive strength of the concrete and the tensile strength of the reinforcing bar gradually decrease, and the exposed concrete undergoes a neutralization phenomenon, causing corrosion of the reinforcing bar. If such a phenomenon occurs through safety diagnosis and inspection, the life of the building can be maintained for a long time only by repairing the section of the concrete structure.

The chipping step is a process of crushing and trimming the section using a machine until undegraded concrete comes out by removing cracked concrete and exposed reinforcing bars from concrete structures that need repair as a result of safety diagnosis and inspection. At this time, it is preferable that the outermost surface of the finished concrete has a rough surface to facilitate the adhesion of the mortar.

2. Primer application

A primer is applied to the trimmed concrete section.

The primer used in the present invention is used to improve the water resistance and durability of the structure, as well as to strengthen the bonding force with the surface of the mortar to be formed later.

The primer used in the present invention is composed of components including cement, admixture, liquid sodium silicate, liquid polysilane and water.

Specifically, the primer used in the present invention includes 10 to 30 parts by weight of cement, 5 to 20 parts by weight of admixture, 15 to 45 parts by weight of liquid sodium silicate, 5 to 20 parts by weight of liquid polysilane, and 55 to 80 parts by weight of water. Is composed.

The cement and admixture play a role in penetrating the damaged part of the structure due to the external environment, reinforcing the structure from harmful substances and increasing the service life.

In the present invention, the admixture is preferably a mixture of fine slag powder and fly ash in a ratio of about 10:1-5.

The liquid sodium silicate is obtained by dissolving water-soluble sodium silicate in water, and a mixing ratio of water: sodium silicate may be mixed and dissolved in a weight ratio of about 100:20 to 100.

The liquid polysilane is obtained by polymerization after mixing a silane monomer in an organic solvent. More specifically, after mixing at least one silane monomer selected from dichloromethylphenylsilane, dichlorodimethylsilane, dichlorodiphenylsilane, dichlorohexylmethylsilane, and dichlorovinylmethylsilane in an organic solvent, a metal catalyst is dispersed and polymerization is performed. After filtering the polymer to separate the silicone polymer, it may be used again obtained by dissolving in an organic solvent.

The primer obtained by the above composition can strengthen the adhesive bonding force with the mortar to be applied later by tightly filling and expanding the voids on the surface of the structure, and can improve physical properties such as water resistance and durability.

3. Mortar composition application

The concrete cross section is chipped to remove concrete and corrosion reinforcement at the deteriorated area, and after applying a primer, a mortar composition is applied to repair.

The mortar composition used in the present invention uses the following composition in order to recycle industrial waste and secure fast setting and adhesion strength with concrete structures.

That is, cement 30-75% by weight, blast furnace quenched slag and blast furnace slow-cooled slag are included in a weight ratio of 7 to 9: 1 to 3, and a powder of 1,000 to 5,000 cm ² /g of synthetic slag fine powder mixture 5 to 45% by weight, 5 to 30% by weight of glass powder having a powderiness of 1,000 to 3,000 cm ² /g, 3 to 20% by weight of shrinkage reducing agent, 0.5 to 1.5% by weight of polymer resin, 0.2 to 2% by weight of fiber, 1 to 5% by weight of silica fume , Clinker 0.5 to 5.0% by weight, plaster 0.5 to 5.0% by weight, alpha-type hemihydrate gypsum 0.5 to 5% by weight, fly ash 0.01 to 5% by weight, red mud 0.1 to 5% by weight, calcined pozzolana 0.01 to 5% by weight, It is used that comprises 100 parts by weight of the binder consisting of 0.01 to 5% by weight of microsilica, 20 to 100 parts by weight of silica and water. At this time, the synthetic slag fine powder mixture is a mechanochemical activated mixture in which a mixture obtained by mixing and pulverizing a plastic composite and a polypropylene porous granular material additionally in the process of finely powdering the blast furnace quenching slag and the blast furnace slow cooling slag It features.

In the present invention, the cement may be Portland cement, slag cement, alumina cement, fast-hardening cement, and the like, preferably Portland cement, and specifically, in the case of Portland cement, the main components are C ₃ S 51%, C ₂ S It is preferably about 25%, C ₃ A 9%, C ₄ AF 9%, and CaSO ₄ 4%, and a specific surface area of about 3,300 cm ² /g.

In the present invention, the synthetic slag cement is obtained as a by-product when producing pig iron at a steel mill, and is a mixture of blast furnace quenching slag produced by rapid cooling and blast furnace slow cooling slag produced by slow cooling in a weight ratio of 7 to 9: 1 to 3 It is obtained by grinding using a ball mill, roller mill, or vibrating mill so that the particle diameter is at the level of 2 to 10 μm.

The blast furnace quenching slag fine powder is an amorphous latent hydraulic material, and is mainly used as an admixture material for concrete, and its advantages include suppression of temperature rise due to heat of hydration, suppression of alkali silica reaction, and improvement of chemical resistance to sulfate or seawater. As can be expected, the neutralization resistance is weak. On the other hand, the blast furnace slow cooling slag fine powder is slow-cooled and crystallized and has no hydraulicity, and a filler having no hydraulicity can exhibit a neutralization inhibitory effect. In addition, if a material that reacts with CO ₂ gas causing neutralization is applied rather than a simple filler, the surface of the cured body is further densified by carbonation reaction, so that it is possible to suppress the penetration of the CO ₂ gas into the inside of the cured body thereafter. As the main component of the blast furnace slow cooling slag, the merilite does not hydrate, but exhibits a carbonation reaction and densifies the structure, thereby making it difficult for CO ₂ gas to penetrate to the surface of the cured body. Therefore, in order to have high durability, the function of making use of the advantages of the blast furnace rapid cooling slag fine powder by mixing the hydraulic blast furnace quenched slag fine powder and the non-hydraulic blast furnace slow cooling slag fine powder, while making use of the advantages of the blast furnace rapid cooling slag fine powder, and supplementing the weak part of the neutralization with the blast furnace slow cooling slag fine powder, a non-hydraulic material. can do.

In forming the binder in the present invention, the synthetic slag fine powder is preferably composed of 5 to 45% by weight. If the synthetic slag fine powder is less than 5% by weight, it is difficult to secure the durability performance to be obtained, and if it exceeds 45% by weight, it takes a long time to obtain the required strength, and there is difficulty in expressing appropriate physical performance. In addition, the synthetic slag fine powder in the present invention is used to prepare a powder of 1,000 ~ 5,000 cm ² /g.

The manufacturing process of the synthetic slag powder is prepared by a mechanochemical activation treatment by mixing and grinding a mixture of the blast furnace quenched slag and the blast furnace slow cooling slag with a plastic composite and polypropylene porous granules further mixed in a vibration mill.

Specifically, the synthetic slag fine powder mixture is prepared by mixing 100 parts by weight of a mixture of the blast furnace quenched slag and the blast furnace slow cooling slag, 0.1 to 10 parts by weight of a plastic composite, and 0.1 to 3.0 parts by weight of a porous polypropylene granular material, followed by mechinochemical activation treatment. .

In the present invention, the plastic composite is characterized by using an aluminum epoxy nanocomposite.

The aluminum-epoxy nanocomposite is a type of ceramic-polymer composite that combines the advantages of organic and inorganic materials. Nanocomposites composed of aluminum and epoxy are known to have a high dielectric constant and are therefore mainly used in the semiconductor field, but have properties that can improve chemical stability and fire resistance due to the specific dielectric constant of a fine nanostructure and metal.

In addition, in the present invention, the porous polypropylene granular material is a flame-retardant material, and is formed into a porous granular material by adding carbon fibers and a flame retardant to a polypropylene resin.

Specifically, a composite is formed by adding and mixing 100 parts by weight of a mixture in which 8 to 16 percent by weight of carbon fibers are added to 84 to 92 percent by weight of polypropylene, 5 to 7 parts by weight of a flame retardant and 1 to 3 parts by weight of a sunscreen agent.

Antimony molybdate and molybdenum oxide may be used as the flame retardant used herein, and a diphenyl acrylate-based sunscreen may be used as the sunscreen.

In the present invention, since the polypropylene porous granular material includes a flame retardant and a sunscreen agent, it serves to improve mechanical performance such as improvement in heat loss, resistance to salt damage, strength improvement, and reduction of heat of hydration.

In the present invention, the mechanochemical activation treatment may be performed by mixing and grinding for 5 to 60 minutes in a vibration mill, more preferably for 10 to 30 minutes.

In the present invention, the mechanochemical activation treatment changes the bonding state of the material through a mechanical pulverization process to change the physicochemical properties of the material. When mixed and pulverized, uniform mixing is possible in the pulverization operation and crystal structure change is achieved. There is an advantage to be able to proceed at the same time. In other words, mechanical impact in the pulverizing system by the mechanochemical activation treatment develops elasticity, plasticity and shear deformation, leading to particle destruction, amorphization, and even chemical reactions in the solid state.

In general, pulverization in the cement field is usually performed using a fine pulverizer such as a ball mill or roller mill.In the case of a ball mill, the pulverizing medium in a rotating cylinder rises up along the inner wall of the cylinder by centrifugal force and then falls, causing an impact force on the pulverized product. The roller mill uses the principle that the pulverized material is pulverized between the roller, the disk and the inner wall by compression and frictional force by rotating the whole at the same time while rotating 3 to 4 rollers on the disk in the mill. On the other hand, a vibrating mill pulverizes the pulverized product down to the micron unit by simultaneously transmitting the impact force and friction force to the pulverized material while the whole mill vibrates by an eccentric circle. It is an equipment that can physically and chemically change the properties of pulverized raw materials by supplying a large amount of pulverization energy to the machine. In other words, the vibrating mill is a pulverizing system suitable for the treatment of mechanochemical activation. It is possible to pulverize the target fine powder in a shorter time than a pulverizing medium such as a conventional ball mill, and because it simultaneously gives shear friction and impact force, it is mixed using a vibration mill. When pulverized, the fine particles of the product are surface-treated, resulting in increased chemical activity as the affinity between particles increases.

In the present invention, the mechanochemical treatment is preferably performed in a vibration mill for 5 to 60 minutes, more preferably 10 to 30 minutes. This is because it is a preferred time to treat the specific surface area of the mixture of the present invention to 1,000 to 5,000 cm ² /g.

The present invention relates to the slag mixture formed by the mechanochemical activation treatment, glass powder, shrinkage reducing agent, polymer resin, fiber, silica fume, clinker, plaster, alpha-type hemihydrate gypsum, fly ash, red mud, calcined pozolana, Microsilica is mixed to form a binder, and 100 parts by weight of the binder, 20 to 100 parts by weight of silica sand, and water are mixed to form a mortar composition.

In the present invention, the glass powder is composed of a silica (SiO ₂ ) component having latent hydraulicity in at least 70% of the chemical components, and the pozzolanic action is activated during a hydration reaction with cement, making it excellent in bonding with a concrete structure. It increases the strength and contributes to the improvement of workability.

In the present invention, the glass powder is preferably used by finely pulverizing what is discharged as an industrial by-product in order to recycle industrial waste. Waste glass, one of the industrial by-products, has a very low recycling rate compared to advanced countries in Korea, and is mainly recycled for road pavement, interior and exterior materials for construction, and road surface painting, but about 30% of waste glass cannot be recycled and is buried in the ground. It is causing a problem. In addition, many studies have been conducted at home and abroad as part of using it as a construction material in order to solve this problem, but most of them remain at the level of replacing aggregates in concrete. The present invention provides a technology for utilizing such waste glass as a mortar for repairing and reinforcing concrete sections.

In the present invention, the glass powder is preferably used in the range of 5 to 30% by weight of the binder. If the content is less than 5% by weight, the compressive strength decreases, and if it exceeds 30% by weight, the compressive strength and workability decrease.

In more detail, the function and effect of the glass powder will be described in more detail. The glass powder, whose main component is a silica component, has a latent hydraulic property. The latent hydraulic property does not have a hardening property by itself, but calcium hydroxide (Ca( Pozzolan action is possible because it reacts with OH) ₂ ) to generate and harden stable insoluble compounds. That is, the calcium oxide (CaO) component in the blast furnace slag fine powder reacts with water to form calcium hydroxide (Ca(OH) ₂ ) and gradually reacts with silica (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ) eluted from the glass powder. Thus, by forming insoluble calcium silicate hydrate (CSH gel) or calcium aluminate hydrate (CAH gel), it makes the structure more dense, contributing to the expression of strength and reinforcement of bonding strength of concrete. The performance of the glass powder used in the present invention varies depending on the degree of powder, but in the present invention, it is preferable to use a glass powder having a powder degree of 1,000 to 3,000 cm ² /g. When the powderiness is less than 1,000 cm ² /g, it may be difficult to control the pozzolanic reaction, and when it exceeds 3,000 cm ² /g, the bonding strength with the concrete structure may decrease.

In addition, in the present invention, the shrinkage reducing agent may be prepared by mixing calcium sulfoaluminate and gypsum in a weight ratio of 4 to 9: 1 to 6, and the amount used is preferably 3% to 20% by weight of the binder. . If the content is less than 3% by weight, it is difficult to control cracking due to initial contraction and expansion, and if it exceeds 20% by weight, it is difficult to secure working time due to a rapid reaction, and there is a problem that may cause abnormal expansion. In the present invention, the gypsum may be used by selecting from phosphate anhydride or hydrofluoric anhydride.

In addition, in the present invention, the polymer resin increases fluidity and improves workability in the state before curing of the mortar composition for reinforcing cross-section of the concrete structure, and in the state after curing, surface adhesion increases, cohesive force increases, flexural strength increases, flexibility It can exhibit effects such as enhancement and waterproofing. In the present invention, the polymer resin is ethylene vinyl acetate (EVA) based, NR (Natural Rubber) based, NBR (Natural Rubber-Butadien Rubber) based, SBR (Styrene-Butadien Rubber) based and polyvinyl acetate (Polyvinyl Any one or a mixture of two or more selected from acetate)-based resins may be used.

In the present invention, the polymer resin is preferably contained in a ratio of 0.5 to 1.5% by weight in the binder. When the content of the polymer resin is less than 0.5% by weight, it is difficult to achieve the effect of enhancing surface adhesion, and when it exceeds 1.5% by weight, it is difficult to produce a hydration product during a hydration reaction, thereby reducing the strength.

In addition, in the present invention, the fiber is effective in initial construction stability after mortar construction, and is used for the purpose of improving initial dispersibility since it can improve flexural strength and tensile strength as well as reduce surface cracks during curing. As the fibers that can be used in the present invention, it is preferable to use those comprising 20 to 50% by weight of polypropylene fibers, 20 to 50% by weight of nylon fibers, and 30 to 60% by weight of arbocel fibers. The arbocel fiber, more specifically, the natural arbocel fiber, is a hydrophilic fiber that prevents surface cracking and improves strength.When mixed with polypropylene fiber and nylon fiber, the advantages of each fiber are maximized and the synergistic effect thereof By exerting, it is possible to increase the strength and reduce the amount of rebound. In the present invention, the fiber is preferably contained in the range of 0.2 to 2% by weight in the binder. If the content is less than 0.2% by weight, the effect of improving tensile strength and flexural strength cannot be seen, and if it exceeds 2% by weight, workability may be deteriorated and economical efficiency may be deteriorated due to an increase in water usage.

In the present invention, the silica fume is an amorphous activated silica as particles having an average particle diameter of about 0.1 to 0.5 mm, and is amorphous active silica, and reacts with calcium hydroxide as in the following formula to change to hydrated calcium silicate at room temperature. It has pozzolanic properties.

3CaOSiO ₂ + H ₂ O → CSH (cement gel) + Ca(OH) ₂

In the present invention, the reason for adding the silica fume to the binder is to improve the dispersibility and water-reduction effect by the ball bearing effect by the spherical particles, improve water tightness and increase strength by the filling effect of silica fume between the cement particles, and the adhesion of shotcrete. This is because there are effects such as reduction of ground amount, suppression of alkali silica reaction, and improvement of chemical resistance through improved performance.

In addition, in the present invention, the clinker is composed of calcium silicate such as allite, berite, and celite. The clinker serves to promote mixing of the binder and water. The clinker is preferably included in the range of 0.5 to 5% by weight in the binder.If the clinker content is less than 0.5% by weight, it is not easy to mix the binder and water, and if it exceeds 5% by weight, the strength is There is a problem of deterioration.

In addition, in the present invention, the plaster (plaster) serves to easily mix the components contained in the binder with water. The plaster is preferably included in the range of 0.5 to 5% by weight in the binder.Therefore, when the content of the plaster is less than 0.5% by weight, there is a problem that various components included in the binder are difficult to be easily mixed with water. If it exceeds 5% by weight, there is a problem that strength and chemical resistance are deteriorated.

In addition, in the present invention, the alpha-type hemihydrate gypsum is obtained by heating dihydrate gypsum under reduced pressure of -600 torr or more at a temperature of about 75 to 100°C for 1 hour or more, and is prepared as alpha-type hemihydrate gypsum by heating under reduced pressure. Alpha-type hemihydrate gypsum exhibits a performance of nearly zero in shrinkage and expansion, and has an effect of suppressing cracks caused by shrinkage and expansion. More specifically, in general, gypsum is largely divided into natural gypsum and chemical gypsum. Usually, the purity is determined according to the content of SO ₃ , and it is classified into dihydrate gypsum, semihydrate gypsum, and anhydrous gypsum according to the content of crystal water in gypsum. do. Dihydrated gypsum transitions to alpha, beta, or anhydrous gypsum depending on the dehydration conditions. When dehydrated in a dry state, it transitions to a beta form, and when dehydrated in a wet state, it transitions to an alpha-type. Alpha-type hemihydrate gypsum has more than 10 times better strength than beta-type hemihydrate gypsum, has a short initial hardening time, and has the effect of suppressing cracking due to shrinkage and expansion. In addition, alpha-type hemihydrate gypsum plays a role of reinforcing high strength, rapid setting, and expandability together with a CSA-based expanding agent to be described later, and compensating for the disadvantages of the CSA-based expanding agent.

In the present invention, the alpha-type hemihydrate gypsum is preferably included in the range of 0.5 to 5% by weight in the binder, and when the content of the alpha-type hemihydrate gypsum is less than 0.5% by weight, resistance to cracking decreases, and 10% by weight If it exceeds %, the reaction speed becomes faster and the pot life is shortened, so there is a problem that the workability is deteriorated.

In addition, in the present invention, the fly ash is a component of silicon oxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ) remaining after burning coal in a facility that uses coal as a fuel such as a thermal power plant. It means that it is left with fine dust. When the fly ash is mixed and used, workability is improved, curing heat is lowered, and long-term strength and watertightness are improved, which is economical. The fly ash is preferably included in the range of 0.01 to 5% by weight in the binder, if the content of the fly ash is less than 0.01% by weight, the adhesion performance of the repair reinforcing agent decreases, and if it exceeds 5% by weight There is a problem that chemical resistance is deteriorated.

In addition, in the present invention, the red mud serves to increase the initial strength of the repair and reinforcing agent according to the present invention, and the main constituents include SiO ₂ and Al ₂ O ₃ and trace amounts of Fe ₂ O ₃ , MgO, Na ₂ Includes O, etc. In the present invention, the red mud is preferably contained in the range of 0.1 to 5% by weight in the binder, and if the content is less than 0.1% by weight, the initial strength improvement effect of the repair and reinforcing agent decreases, and exceeds 5% by weight. In this case, the strength enhancing effect is no longer increased.

In addition, in the present invention, the calcinated pozzolana is prepared by adding calcium to natural pozzolana, which is mainly composed of fine red volcanic soil, and serves to improve the waterproofness of the repair and reinforcement agent according to the present invention. do. Specifically, the calcined porolana is a mixture obtained by mixing 1 to 20 parts by weight of calcium with 100 parts by weight of natural pozzolana, and then calcined at 1000 to 1200°C for 0.5 to 1 hour, and then pulverized to have an average particle size of 10 to 20 μm. It is desirable to do. When applied to a mortar, the calcined pozzolana treated as described above serves to improve the compactness of the tissue, thereby increasing the waterproofness and strength. The calcined pozzolana is preferably included in the range of 0.01 to 5% by weight in the binder, but when the content of calcined pozolana is less than 0.01% by weight, the waterproofness of the repair and reinforcing agent decreases, and when it exceeds 5% by weight There is a problem that the strength of the repair and reinforcing agent decreases.

In addition, in the present invention, the microsilica is a silica particle having a particle diameter of 10 to 200 μm, and serves to improve the strength and chemical resistance of the repair reinforcing agent according to the present invention. The microsilica is preferably included in the range of 0.01 to 5% by weight in the binder, and if the content of the microsilica is less than 0.01% by weight, the strength and chemical resistance of the repair reinforcing agent decreases, and when it exceeds 5% by weight There is a problem that the adhesion performance of the repair and reinforcing agent is deteriorated.

In addition, for repair and reinforcement of the underwater concrete structure, an underwater non-separating agent may be additionally included in the binder in the range of 0.1 to 3% by weight. The non-separating agent in water is added to prevent decomposition by improving the viscosity of the mortar composition in water, and includes methyl cellulose, such as methyl cellulose, hydroxymethyl cellulose, and carboxymethyl cellulose; Ethyl cellulose such as ethyl cellulose, hydroxyethyl cellulose, and carboxyethyl cellulose; Cellulose-based thickeners selected from propyl-based cellulose such as hydroxypropyl cellulose can be used. The content is preferably contained in an amount of 0.1 to 3% by weight of the binder because it exhibits an appropriate viscosity. If necessary, in order to further increase the viscosity in water, a water-soluble acrylic resin powder may be further added. It is preferable to use the water-soluble acrylic resin powder in an amount of 1 to 30% by weight of the water insoluble agent.

In addition, if necessary, based on 100 parts by weight of the binder, 0.1 to 10 parts by weight of a dispersant, 0.01 to 3 parts by weight of an antifoaming agent, and 0.01 to 10 parts by weight of a retarder may further include one or more additives selected from.

The dispersant adsorbs on the surface of the mortar particles and gives a charge to the surface of the particles, causing a mutual reaction between the particles, thereby dispersing the agglomerated particles to increase the flow, thereby enhancing the strength due to the water reducing effect. As the dispersant, a conventional water reducing agent may be used, and for example, it may be used alone or in combination of two or more from the group consisting of lignin sulfonate, polynaphthalene sulfonate, polymelamine sulfonate, or polycarboxylate-based water reducing agent. The content of the dispersant is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the binder.

The antifoaming agent is used to improve the strength and appearance of the mortar by removing large pores in the mortar. Defoamers include mineral oil-based antifoaming agents such as kerosene and liquid paraffin; Oil and fat antifoaming agents such as animal and vegetable oil, sesame oil, castor oil and alkylene oxide adducts thereof; Fatty acid-based antifoaming agents such as oleic acid, stearic acid, and alkylene oxide adducts thereof; Fatty acid ester antifoaming agents such as glycerin monoricinolate, alkenyl succinic acid fluid, sorbitol monoraulate, sorbitol trioleate, and natural wax; Polyoxyalkylenes, (poly)oxyalkyl ethers, acetylene ethers, (poly)oxyalkylene fatty acid esters, (poly)oxyalkylene sorbitan fatty acid esters, (poly)oxyalkylenealkyl (aryl) ethers Oxyalkylene antifoaming agents such as sulfate ester salts, (poly) oxyalkylene alkyl phosphate esters, (poly) oxyalkylene alkyl amines, and (poly) oxyalkylene amides; Alcohol-based antifoaming agents such as octyl alcohol, hexadecyl alcohol, acetylene alcohol, and glycols; Amide antifoaming agents such as acrylate polyamine; Phosphate ester antifoaming 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 dimethyl silicone oil, silicone paste, silicone emulsion, organically modified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil, and the like can be used. It is preferable to use 0.01 to 3 parts by weight of the antifoaming agent based on 100 parts by weight of the binder.

The retarder may be added for the purpose of securing workability for a certain period by adjusting the hydration rate of the binder. As retarding agents, boric acid and borax, borates such as sodium borate, potassium borate, gluconic acid, citric acid, tartaric acid, glucoheptonic acid, arabonic acid, malic acid or citric acid and their sodium, potassium, calcium, magnesium, ammonium, triethanolamine Oxycarboxylic acids such as inorganic salts or organic salts such as; Monosaccharides such as glucose, fructose, galactose, saccharose, xylose, abitose, lipose, and isomerized sugar, oligosaccharides such as disaccharides and trisaccharides, or oligosaccharides such as dextrin, or polysaccharides such as dextran, Sugars such as molasses containing these; Sugar alcohols such as sorbitol; Magnesium silicide; Phosphoric acid and its salts or boric acid esters; Aminocarboxylic acids and salts thereof; Alkali-soluble protein; Fumic 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 their alkali metal salts, alkalis Phosphonic acids, such as earth metal salts, and derivatives thereof can be used. The content is preferably 0.01 to 10 parts by weight based on 100 parts by weight of the binder.

The present invention is a synthetic slag powder, glass powder, shrinkage reducing agent, polymer resin, fiber, silica fume, clinker, plaster, alpha-type hemihydrate gypsum, fly comprising a mixture of cement, blast furnace quenching slag and blast furnace slow cooling slag as described above. A dry mortar premix composition is prepared by mixing silica sand with a binder composed of ash, red mud, calcined pozzolana, and microsilica, and a predetermined water is mixed thereto to form a mortar composition. In the present invention, the binder and the silica sand are preferably mixed in a ratio of 100 parts by weight of the binder and 20 to 80 parts by weight of the silica sand. In addition, the amount of water used may be included in an amount of 5 to 40 parts by weight, but it can be changed according to use.

In the present invention, the silica sand is not particularly limited, but a mixture of medium particles having an average particle diameter of 10 to 20 mm and fine fibers having an average particle diameter of 0.1 to 1.0 mm may be used in a ratio of 1:4 to 2:3, respectively. When the average particle size and content of the silica sand are within the above range, the fluidity and density of the mortar composition may be improved.

The mortar composition obtained as described above is applied to the surface to be constructed to repair and reinforce the cross section of the concrete structure.In the case of repeated construction more than once, the surface is polished for adhesion to the target surface to finish roughly. It is preferable to construct and plaster at 5 to 15 mm for the first pouring, 20 to 50 mm for the second and third pouring, and 5 to 15 mm for the final pouring using a trowel, but the thickness depends on the thickness of the chipped concrete. you can change it.

4. Surface coating agent application

The mortar composition is applied to the concrete crushed area, finished smoothly, and dried, and then a surface coating agent according to the present invention is applied thinly to the surface to reinforce the repaired surface from external conditions.

The surface coating agent used in the present invention is a water-based epoxy-based paint.

In the present invention, the water-based epoxy-based paint is used as a water-based epoxy-based paint comprising an epoxy main material, an amine-based curing agent, and water.

Specifically, the water-based epoxy-based paint is a water-based epoxy-based paint comprising an epoxy base material, an amine-based curing agent, and water, and the epoxy base material is a liquid epoxy resin 20 to 40 parts by weight, a hydroxyl group-containing polyester resin 5 to 10 parts by weight, vanadium Acid metal salt 0.2 to 2.0 parts by weight, water 10 to 30 parts by weight, dispersant 0.5 to 2.0 parts by weight, antifoaming agent 0.2 to 1.0 parts by weight, thickener 0.2 to 2.0 parts by weight, extender pigment 5 to 20 parts by weight, wetting agent 0.2 to 2.0 parts by weight The amine-based curing agent is composed of 30 to 60 parts by weight of an amine compound, 20 to 40 parts by weight of water, 0.2 to 2.0 parts by weight of an antifoaming agent, 0.2 to 3.0 parts by weight of a thickener, and the epoxy subject: amine curing agent The mixing ratio of is mixed at a weight ratio of 10:3 to 10, and water is added in an amount of 100 to 500 parts by weight based on 100 parts by weight of the mixture of the epoxy main agent and the amine-based curing agent.

First, as the epoxy main component, 20 to 40 parts by weight of a liquid epoxy resin, 5 to 10 parts by weight of a polyester resin containing a hydroxyl group, 0.2 to 2.0 parts by weight of a vanadium acid metal salt, 10 to 30 parts by weight of water, 0.5 to 2.0 parts by weight of a dispersant , 0.2 to 1.0 parts by weight of antifoam, 0.2 to 2.0 parts by weight of thickener, 5 to 20 parts by weight of extender pigment, 0.2 to 2.0 parts by weight of wetting agent.

The liquid epoxy resin may be a bisphenol A-based liquid epoxy resin, and the bisphenol A-based liquid epoxy resin serves to improve adhesion and bonding strength.

The hydroxyl group-containing polyester resin may be a polyester resin containing a hydroxyl group or a modified resin thereof, and specifically, a polycondensate of a polyhydric alcohol and a polybasic acid may be used. At this time, the polyhydric alcohol is ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, polycarrolactone polyol, glycerin , Sorbitol, and the like, and the polybasic acid is phthalic acid, phthalic anhydride, tetrahydrophthalic acid, tetrahydrophthalic anhydride, trimellitic acid, trimellitic anhydride, terephthalic acid, fumaric acid, itaconic acid, adipic acid, succinic acid, cyclo It may be selected and used from hexane-1,4-dicarboxylic acid and the like.

In addition, examples of the modified resin of the polyester resin containing a hydroxyl group include a urethane modified polyester resin, an epoxy modified polyester resin, an acrylic modified polyester resin, and a silicone modified polyester resin.

It is preferable to use the hydroxyl group-containing polyester resin or modified resin thereof having a number average molecular weight of 3000 to 50,000 and a glass transition temperature of 20 to 100°C.

The vanadium acid metal salt serves to improve the corrosion resistance of the paint, and is characterized in that it is made of water-soluble. As a specific example, calcium vanadate, potassium vanadate, or the like can be used.

The dispersant is used to ensure color uniformity by dispersing the extender pigment in the liquid phase when the main substance is mixed. As such a dispersant, it may be used by selecting from a nonionic type or an anionic type.

The antifoaming agent is used to form an even coating film by suppressing bubbles of the main material, and a nonionic or silicon-based antifoaming agent may be used.

The thickener is used to prevent sedimentation of the extender pigment and improve workability, and specifically, may be used by selecting from bentonite-based, urethane-based, and acrylic-based thickeners.

The extender pigment serves to improve the strength of the coating film, and improves adhesion to the overcoat due to irregularities on the surface of the coating film, thereby improving moisture resistance and water resistance. The extender pigment used in the present invention may be selected from calcium carbonate, barium sulfate, mud, talc, mica, and silica.

In the present invention, the wetting agent serves to provide hydrophilicity to the material so that the water-soluble epoxy resin coating film can be smoothly formed. Specifically, a hydroxyethyl cellulose-based wetting agent may be used.

The amine-based curing agent serves to accelerate the curing of the handmade epoxy component.

Specific components of the amine-based curing agent include 30 to 60 parts by weight of an amine compound, 20 to 40 parts by weight of water, 0.2 to 2.0 parts by weight of a defoaming agent, and 0.2 to 3.0 parts by weight of a thickener.

The amine compound may be selected from aliphatic, aromatic, and alicyclic amine compounds, and the amine equivalent is 100 to 320 g/eq, and it is preferable to use one having a room temperature viscosity of 30 to 40,000 cps.

Other components such as the antifoaming agent and the thickening agent may be the same or different from those used in the epoxy main component.

In order to form the water-based epoxy-based paint in the present invention, the mixture ratio of the epoxy main material: the amine curing agent is mixed at a weight ratio of 10:3 to 10, and water is added to 100 parts by weight of the mixture of the epoxy main material and the amine curing agent. It is preferable to use a paint obtained by post-adding in an amount of 100 to 500 parts by weight.

Then, after the water-based epoxy-based paint is cured and cured, a water-based urethane-based paint is applied to the surface to which the water-based epoxy-based paint is applied.

In the application of the water-based urethane-based paint, a water-based urethane-based paint comprising a water-dispersible acrylic urethane resin, an extender pigment, and silane is applied.

Specifically, the water-based urethane-based paint is 50 to 80 parts by weight of a water-dispersed acrylic urethane resin, 0.2 to 2.0 parts by weight of a dispersant, 0.5 to 2.0 parts by weight of a thickener, 5 to 20 parts by weight of an extender, 0.2 to 2.0 parts by weight of an antifoam, 0.2 to a silane. It is characterized in that it comprises 2.0 parts by weight and 0.2 to 5.0 parts by weight of a co-solvent.

The aqueous dispersion acrylic urethane resin is 2-hydroxyethyl methacrylate (2-HEMA: 2-hydroxyethyl methacrylate), methyl methacrylate (MMA: methyl methacrylate), n-butyl acrylate (n-BA: n-butyl acrylate) and acrylic acid (AAc: acrylic acid), and a polyurethane acrylate hybrid emulsion synthesized by adding an anionic or nonionic emulsifier and an initiator may be used. The water-dispersible acrylic urethane resin is environmentally friendly because it dries quickly and exhibits excellent weather resistance, durability, and UV stability even under external exposure conditions, and is water-soluble.

The dispersant is for forming a coating film of uniform color by evenly dispersing the extender pigment in the liquid when the water-soluble urethane-based paint is mixed. In the present invention, a nonionic type polyoxyalkylene type surfactant or an anionic type polycarboxyl salt type Any one selected from surfactants may be used.

The thickener is to prevent sedimentation of the pigment and improve workability during painting. In the present invention, any one selected from bentonite-based, urethane-based, and acrylic-based may be used.

The extender pigment is for color expression of a water-soluble urethane-based paint, and any one selected from red iron oxide, titanium dioxide, yellow iron oxide, and carbon black may be used.

The antifoaming agent is for forming an even coating film by suppressing air bubbles in the water-soluble urethane-based paint, and in the present invention, any one selected from nonionic or silicone may be used.

The silane is used to improve adhesion and to improve water resistance and durability of the coating film, and includes glycidoxypropyl methyldiethoxy silane, gamma methacryloxy propyl triethoxysilane, gammaglycidoxy propyl triethoxy silane, gammaamino Any one selected from propyl triethoxy silane and vinyl trimethoxy silane may be used.

The co-solvent is to increase the dissolving power of the solvent to facilitate the shape of the coating film, and any one selected from texanol, butyl acetate, and butyl cellosolve may be used.

The surface coating applied in the above method is excellent in bonding strength and durability with the surface of the mortar as a conductor by using the above-described eco-friendly coating composition, and in particular, it has excellent properties such as chemical resistance, water resistance, and salt damage resistance to reinforce the surface of concrete structures. The effect is excellent. In addition, since it is water-soluble and does not elute organic solvents or heavy metals, it is environmentally friendly, and since the life of the painting can be extended, the reinforcing effect of the structure surface can be maintained for a long time.

Hereinafter, the present invention will be described in more detail based on examples. However, the scope of the present invention is not limited by the following examples.

[Example]

(Production Example 1) Preparation of mortar composition

The blast furnace quenching slag and the blast furnace slow cooling slag are 8:2 in a weight ratio of 8:2 to 100 parts by weight of the mixture, 1.5 parts by weight of aluminum epoxy nanocomposite, and polypropylene porous granules (PP resin 90: carbon fiber 10: antimony polybdic acid flame retardant 5, ultraviolet rays Granular material formed by mixing at the weight ratio of blocking agent 3) Synthesis consisting of a mixture treated with a specific surface area of 1,000 to 5,000 cm ² /g through mechanochemical activation treatment of mixing and pulverizing a mixture of 1.0 part by weight in a vibration mill A fine slag powder was prepared.

Portland cement 50 parts by weight, 20 parts by weight of the obtained synthetic slag fine powder, 15 parts by weight of glass powder having a fineness of about 2,000 cm ² /g, shrinkage in which calcium sulfol aluminate and phosphate anhydride are mixed at a weight ratio of 7:3 5 parts by weight of reducing agent, 1.0 part by weight of polymer resin (EVA resin), 1.0 part by weight of fiber (a mixture of 30 parts by weight of polypropylene, 40 parts by weight of nylon and 30 parts by weight of arbocel fiber), 2.0 parts by weight of silica fume, 2 parts by weight of clinker Part, 1 part by weight of plaster, 1.5 parts by weight of alpha-type hemihydrate gypsum, 2.5 parts by weight of fly ash, 1.5 parts by weight of red mud, 3.5 parts by weight of calcined fossilana, and 3 parts by weight of microsilica were mixed to prepare a binder.

55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyeonggi Mining) and 20 parts by weight of water are mixed with 100 parts by weight of the binder, in which medium particle diameter of 10 to 20 mm and fine yarn with 0.1 to 1.0 mm are mixed in a ratio of 2:3 Thus, a mortar composition was prepared.

(Production Example 2) Preparation of mortar composition

The blast furnace quenching slag and the blast furnace slow cooling slag are 8:2 in a weight ratio of 8:2 to 100 parts by weight of the mixture, 9 parts by weight of aluminum epoxy nanocomposite, and polypropylene porous granules (PP resin 90: carbon fiber 10: polybdic acid antimony flame retardant 5, ultraviolet rays A granular material formed by mixing at the weight ratio of the blocking agent 3) Synthesis consisting of a mixture treated with a specific surface area of 1,000 to 5,000 cm ² /g through mechanochemical activation treatment of mixing and pulverizing a mixture of 3.0 parts by weight in a vibration mill A fine slag powder was prepared.

Portland cement 50 parts by weight, 20 parts by weight of the obtained synthetic slag fine powder, 15 parts by weight of glass powder having a fineness of about 2,000 cm ² /g, shrinkage in which calcium sulfol aluminate and phosphate anhydride are mixed at a weight ratio of 7:3 5 parts by weight of reducing agent, 1.0 part by weight of polymer resin (EVA resin), 1.0 part by weight of fiber (a mixture of 30 parts by weight of polypropylene, 40 parts by weight of nylon and 30 parts by weight of arbocel fiber), 2.0 parts by weight of silica fume, 2 parts by weight of clinker Part, 1 part by weight of plaster, 1.5 parts by weight of alpha-type hemihydrate gypsum, 2.5 parts by weight of fly ash, 1.5 parts by weight of red mud, 3.5 parts by weight of calcined fossilana, and 3 parts by weight of microsilica were mixed to prepare a binder.

55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyeonggi Mining) and 20 parts by weight of water are mixed with 100 parts by weight of the binder, in which medium particle diameter of 10 to 20 mm and fine yarn with 0.1 to 1.0 mm are mixed in a ratio of 2:3 Thus, a mortar composition was prepared.

(Comparative Preparation Example 1) Preparation of mortar composition

Only Portland cement was used as the binder.

55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyeonggi Mining), and 20 parts by weight of silica sand obtained by mixing 100 parts by weight of the Portland cement binder with medium and 0.1 to 1.0 mm fine yarn with an average particle diameter of 10 to 20 mm in a ratio of 2:3 Mixing parts by weight to prepare a mortar composition.

(Comparative Preparation Example 2) Preparation of mortar composition

Portland cement 65 parts by weight, blast furnace quenching slag and blast furnace slow cooling slag are mixed in a weight ratio of 8:2, and 20 parts by weight of synthetic slag fine powder having an average particle diameter of 2 to 10 µm, calcium sulfol aluminate and phosphate anhydride gypsum are 7:3 A binder was prepared by mixing 5 parts by weight of a shrinkage reducing agent, 1.0 part by weight of a polymer resin (EVA resin), 1.0 part by weight of cellulose fiber, and 0.5 part by weight of sodium hydrogen carbonate mixed in a weight ratio of.

55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyeonggi Mining) and 20 parts by weight of water are mixed with 100 parts by weight of the binder, in which medium particle diameter of 10 to 20 mm and fine yarn with 0.1 to 1.0 mm are mixed in a ratio of 2:3 Thus, a mortar composition was prepared.

(Comparative Preparation Example 3) Preparation of Mortar Composition

Portland cement 65 parts by weight, blast furnace quenching slag and blast furnace slow cooling slag are mixed in a weight ratio of 8:2, and 20 parts by weight of synthetic slag fine powder having an average particle diameter of 2 to 10 µm, calcium sulfol aluminate and phosphate anhydride gypsum are 7:3 Shrinkage reducing agent 5 parts by weight, polymer resin (EVA resin) 1.0 parts by weight, cellulose fiber 1.0 parts by weight and sodium hydrogen carbonate 0.5 parts by weight, water non-separating agent (methylcellulose) 0.5 parts by weight, dispersant (PC Total) 0.5 parts by weight, 0.2 parts by weight of a defoaming agent, and 0.05 parts by weight of a retarder (tartaric acid) were added and mixed to prepare a binder.

55 parts by weight of silica sand, 9.5 parts by weight of limestone (Gyeonggi Mining) and 20 parts by weight of water are mixed with 100 parts by weight of the binder, in which medium particle diameter of 10 to 20 mm and fine yarn with 0.1 to 1.0 mm are mixed in a ratio of 2:3 Thus, a mortar composition was prepared.

(Production Example 3) Preparation of surface coating agent

A primer formed by mixing 15 parts by weight of portland cement, 10 parts by weight of an admixture composed of a mixture of slag powder and fly ash, 30 parts by weight of liquid sodium silicate, 10 parts by weight of liquid polysilane, and 60 parts by weight of water was prepared.

As an aqueous epoxy-based paint, 30 parts by weight of bisphenol A type epoxy resin, 8.5 parts by weight of epoxy-modified polyester resin (number average molecular weight of about 20,000 and glass transition temperature of about 80°C), calcium vanadate 1.0 parts by weight, water 20 parts by weight , 1.0 parts by weight of dispersant, 0.5 parts by weight of antifoam, 0.5 parts by weight of thickener, 10 parts by weight of extender, 0.8 parts by weight of wetting agent are mixed to obtain a main component, 40 parts by weight of amine compound, 30 parts by weight of water, 0.8 parts by weight of antifoam, thickener After mixing 1.5 parts by weight to obtain a curing agent component, the mixture was mixed at a weight ratio of 10:5 in the mixing ratio of the main substance: the curing agent, and water was added in an amount of about 300 parts by weight based on 100 parts by weight of the mixture of the main substance and the curing agent. I did.

As an aqueous urethane-based paint, a paint was prepared by mixing 60 parts by weight of a water-dispersible acrylic urethane resin, 1.0 part by weight of a dispersant, 0.9 part by weight of a thickener, 15 parts by weight of an extender, 0.9 parts by weight of an antifoam, 1.5 parts by weight of silane, and 2.5 parts by weight of a co-solvent. .

(Comparative Preparation Example 4) Preparation of surface coating agent

It was prepared in the same manner as in Preparation Example 3, but the preparation of the primer was omitted.

(Comparative Preparation Example 5) Preparation of surface coating agent

It was prepared in the same manner as in Preparation Example 3, but the preparation of the water-based epoxy-based paint was omitted.

(Comparative Preparation Example 6) Preparation of surface coating agent

It was prepared in the same manner as in Preparation Example 3, but the preparation of the aqueous urethane-based paint was omitted.

[Example 1]

After chipping and crushing the cross section of the damaged concrete structure, removing the rusty reinforcing bar inside, applying a primer and drying it, and then applying the mortar composition prepared in Preparation Example 1 to smooth the surface of the structure and curing it. . The surface coating agent prepared in Preparation Example 3 was coated on the surface of the cured mortar to a total thickness of 200 μm in the order of a water-based epoxy-based paint and a water-based urethane-based paint, followed by curing and drying to complete the repair and reinforcement work.

[Comparative Example 1]

It was carried out in the same manner as in Example 1, except that only the surface was painted using the surface coating agent prepared in Comparative Preparation Example 4.

[Comparative Example 2]

It was carried out in the same manner as in Example 1, except that only the surface was painted using the surface coating agent prepared in Comparative Preparation Example 5.

[Comparative Example 3]

It was carried out in the same manner as in Example 1, except that only the surface was painted using the surface coating agent prepared in Comparative Preparation Example 6.

Performance evaluation

1. Physical properties of mortar composition

A test body was prepared using the mortar prepared in Preparation Examples 1 to 2 and Comparative Preparation Examples 1 to 3, and physical properties were measured by the following test method.

1) Setting time: KSF 2436

2) Flexural strength: KS F 2476 「Strength test method of polymer cement mortar」

3) Compressive strength: KSF 2405

4) Bond strength: KS F 4716 「Strength test method of polymer cement mortar」

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

6) Flow: Conducted according to KS L 5220

The results are shown in Table 1 below.

Item Manufacturing Example 1 Manufacturing Example 2 Comparative Production Example 1 Comparative Production Example 2 Comparative Production Example 3 Setting time (minutes) Initial decision 39 42 120 53 60 closing 48 49 245 95 105 Flexural strength
(N/mm ² ) mourning 20 22 9 8 7 Underwater 10 11 8 7 6 Compressive strength
(N/mm ² ) mourning 72 78 46 49 51 Underwater 60 62 47 45 48 Adhesion strength
(N/mm ² ) mourning 3.9 4.0 3.5 1.0 2.2 Underwater 2.2 2.4 0.9 0.9 1.2 Length change rate (%) 0.001 0.002 -0.27 0.15 0.16 Flow(mm) 128 130 135 118 120

As shown in Table 1, in the case of the mortar composition using the binder according to the present invention, it can be confirmed that the physical properties are remarkably superior to the mortar composition when the conventional Portland cement is used as the binder or the glass powder is not used. .

2. Evaluation of rust prevention, adhesion strength, acid resistance, bending resistance, and water resistance

The rust prevention properties, adhesion strength, acid resistance, bending resistance, and water resistance of the coating films formed according to Example 1 and Comparative Examples 1 to 3 were evaluated, and the results are shown in Table 2.

Sample Anti-rust (ASTM D610) Adhesion strength (KSM6715-01)
(kgf/㎠) Acid resistance
(KSMSI02812-1-02) Flexibility resistance
(KS M 5000-03, Φ10mm, 180° bending) Water resistance
(KSMSI02812-2-02) Example 1 0.1% or less 39 clear clear clear Comparative Example 1 0.2% or less 31 clear clear clear Comparative Example 2 0.3% or less 32 clear clear clear Comparative Example 3 0.2% or less 32 clear clear clear

From the results of Table 2, it can be seen that when the coating using the coating composition prepared in the present invention is applied, it has excellent properties in adhesion strength and excellent results in other physical properties.

3. Flame retardancy, weather resistance, chloride ion penetration resistance, impact resistance evaluation

The flame retardancy, weather resistance, chloride ion penetration resistance, and impact resistance of the mortar and coating film formed according to Example 1 and Comparative Examples 1 to 3 were evaluated. (Flame retardancy was evaluated by the method of UL94, and other properties were evaluated by the method of KS F 4929 (2010))

As a result of the evaluation, in the case of flame retardancy, all samples showed self-extinguishing properties, and in other physical properties, all samples showed appropriate or no abnormal results.

From the above experimental results, it was confirmed that when the surface reinforcement construction of a concrete structure was performed using the mortar and surface coating agent according to the present invention, it had excellent physical properties such as excellent mechanical properties and chemical properties.

As described above, in the present specification and drawings, a preferred embodiment of the present invention has been disclosed, and although specific terms are used, this is only used in a general meaning to easily explain the technical content of the present invention and to aid understanding of the invention. , It is not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is apparent to those of ordinary skill in the art that other modified examples based on the technical idea of the present invention may be implemented.

Claims (5)

(1) chipping the cross section of the concrete structure that needs to be repaired to trim until an undamaged part comes out;
(2) applying a primer containing cement, admixture, liquid sodium silicate, liquid polysilane, and water to the polished concrete cross section;
(3) Cement 30-75% by weight, blast furnace quenching slag, and blast furnace slow cooling slag are included in a weight ratio of 7 to 9: 1 to 3 on the surface of the cross section to which the primer is applied, and the powder is 1,000 to 5,000 cm ² /g. Synthetic slag fine powder mixture 5~45% by weight, 5~30% by weight of glass powder having a powderiness of 1,000~3,000 cm ² /g, 3~20% by weight of shrinkage reducing agent, 0.5~1.5% by weight of polymer resin, 0.2~2 fiber Wt%, silica fume 1 to 5 wt%, clinker 0.5 to 5.0 wt%, plaster 0.5 to 5.0 wt%, alpha-type hemihydrate gypsum 0.5 to 5 wt%, fly ash 0.01 to 5 wt%, red mud 0.1 to 5 wt% , Comprising comprising 100 parts by weight of a binder consisting of 0.01 to 5% by weight of calcined fozolana, 0.01 to 5% by weight of microsilica and 20 to 100 parts by weight of silica sand and water,
The synthetic slag fine powder mixture is a mechanochemical-activated mixture in which a mixture obtained by mixing and pulverizing a plastic composite and a polypropylene porous granular material additionally in a process of finely powdering the blast furnace quenching slag and the blast furnace slow cooling slag is mixed and pulverized in a vibration mill. Applying the mortar composition; And
(3) A water-based epoxy-based paint comprising an epoxy main material, an amine-based curing agent, and water is applied to the surface to which the mortar composition is applied, and a water-dispersible acrylic urethane resin, an extender pigment, and Applying a surface coating agent by applying an aqueous urethane-based paint comprising silane; As an eco-friendly repair and reinforcement method of a cross section of a concrete structure comprising a,
In the above (3), the plastic composite is characterized in that the aluminum epoxy nanocomposite,
In the above (3), the polypropylene porous granular material is a mixture of 84 to 92% by weight of polypropylene resin and 8 to 16% by weight of carbon fiber added to 100 parts by weight of a flame retardant 5 to 7 parts by weight and 1 to 3 parts by weight of a sunscreen agent. It is characterized in that it is a porous granular body, wherein antimony molybdate or molybdenum oxide is used as the flame retardant, and a diphenyl acrylate-based sunscreen is used as the sunscreen,
The synthetic slag fine powder mixture in (3) is characterized by mixing 100 parts by weight of a mixture of the blast furnace quenching slag and the slow cooling blast furnace slag, 0.1 to 10 parts by weight of a plastic composite, and 0.1 to 3.0 parts by weight of a porous polypropylene granule. Eco-friendly repair and reinforcement method of the cross section of concrete structure.
The method according to claim 1, wherein the polymer resin in (3) is ethylene vinyl acetate (EVA) based, NR (natural rubber) based, NBR (Natural Rubber-Butadien Rubber) based, SBR (Styrene-Butadien Rubber). Use any one or a mixture of two or more selected from polyvinyl acetate-based resins, and the fibers are polypropylene fibers 20-50% by weight, nylon fibers 20-50% by weight, and arbocel fibers 30-60 Eco-friendly repair and reinforcement method of a concrete structure section, characterized in that made, including weight percent.
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