KR102640197B1 - Light-weighted cement mortar improved in adhesion, Repair and reinforcement materials containing the same and Method of repair and reinforcement of concrete structure using the same - Google Patents

Abstract

The present invention relates to ultra-fast hardening lightweight cement mortar. More specifically, the ultra-fast hardening lightweight cement mortar as a repair reinforcement for concrete structures is ultra-fast hardening, lightweight and has improved adhesion to concrete structures. Repair of concrete structures using the same. This invention relates to reinforcing materials and a method of repairing and reinforcing concrete structures using the same.

Description

Light-weighted cement mortar with improved adhesion, fast-hardening lightweight cement mortar for concrete structures using the same, and repair and reinforcement construction methods for concrete structures using the same. repair and reinforcement of concrete structure using the same}

The present invention relates to a rapid hardening lightweight cement mortar that improves the adhesion of a fast hardening repair reinforcement applied to concrete repair and reinforcement, a quick hardening lightweight repair reinforcement for a concrete structure using the same, and a repair and reinforcement construction method for a concrete structure using the same.

In general, reinforced concrete structures include concrete members and reinforcing bars installed inside the concrete members to reinforce strength. These reinforced concrete structures are used in bridges, tunnels, underpasses, covered structures, etc., and deteriorate due to the quality of concrete and reinforcing bars, environmental factors, physical factors, etc.

Concrete structures are known to be usable semi-permanently, but recent results of numerous surveys and studies on existing structures show that concrete structures also experience deterioration over time and lose their original functions in less than a few decades. Cases of this are often reported. Therefore, when a concrete structure deteriorates and cracks occur, it is necessary to quickly repair the deteriorated area.

The probability of chemical corrosion problems occurring in a general environment is very small, and organic matter contained in domestic sewage reacts with bacteria to produce sulfate ions, which erodes concrete, or is damaged by acidic substances such as hot springs or acid rain. In most cases, concrete structures are corroded due to salt damage or salt damage to reinforced concrete structures located in marine environments. Structures subject to chemical corrosion include sewage pipes and covering structures, underground structures, water retention structures, marine concrete, chemical plants, food plants, livestock barn floors, and underground structures in soil contamination and hot spring areas.

In the case of these concrete structures, the required quality cannot be secured with cement-based materials alone, so polymer cement concrete made by mixing cement and polymer and polymer concrete using polymer, or the pores of concrete, which are the main penetration path for chloride ions, are impregnated with synthetic resin. It is suggested to use polymer impregnated concrete. However, because existing polymer concrete has low acid and salt resistance, it is insufficient to prevent concrete corrosion caused by chemical erosion, especially in concrete structures, water-stop structures, marine concrete structures, and underwater concrete structures under harsh environments. In addition, in the case of fast-hardening repair and reinforcement agents applied to concrete structures, there is a problem of low long-term stability due to insufficient bonding force with the repair and reinforcement parts.

Republic of Korea Patent No. 10-0299410 (announcement date 2001.09.03) Republic of Korea Patent No. 10-1368219 (announcement date 2014.02.27) Republic of Korea Patent No. 10-1670410 (announcement date 2016.11.01)

Accordingly, the present inventors have made extensive research efforts to overcome the problems of the above-described prior technologies, and as a result, have developed a method that can increase the miscibility between lightweight cement mortar compositions and increase the bonding properties of fast-hardening mortar to concrete structures and the bonding force between mortar components. By introducing adhesion improvers and adhesion aids, a new repair and reinforcement construction method that can secure excellent physical properties without additional surface reinforcement treatment on damaged concrete structures and the composition and composition ratio of fast-hardening lightweight cement mortar applied thereto were discovered, leading to the present invention. It has been completed.

That is, the present invention seeks to provide a rapid hardening lightweight cement mortar, a quick hardening lightweight repair reinforcement for a concrete structure using the same, and a repair and reinforcement construction method for a concrete structure using the same.

Accordingly, the technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. You will be able to.

The fast-setting lightweight cement mortar of the present invention for solving the above problems includes mixed cement, fine aggregate, quick-setting agent, quick-setting aid, anti-shrinkage agent, dispersant, strength enhancer, durability enhancer, adhesion improver, adhesion aid, curing retardant, and plaster improver. , waterproofing agents and water repellent agents.

As a preferred embodiment of the present invention, the mixed cement in the cement mortar composition may include one type of Portland cement, ultrafine particle cement, and alumina cement in a weight ratio of 1:0.20 to 0.35:0.05 to 0.15.

As a preferred embodiment of the present invention, the fine aggregate in the cement mortar composition may include one or more selected from silica sand, bottom ash, blast furnace slag, cenosphere, and silica airgel.

In a preferred embodiment of the present invention, the quick setting agent in the cement mortar composition includes 25 to 35% by weight of bauxite, 0.2 to 1.5% by weight of anti-flow agent, 8.0 to 12.0% by weight of fast setting additive, and 5.0 to 10.0% by weight of setting aid. The remaining amount of calcium sulfoaluminate may be included in the total weight percent.

As a preferred embodiment _of the present invention, the quicksetting aid in the cement mortar composition may include _Na2SO4 .

As a preferred embodiment of the present invention, the anti-shrinkage agent in the cement mortar composition may include a compound represented by the following formula (1).

[Formula 1]

(RCH ₂ CH ₂ CH=CH) _n SiO

In Formula 1, R is a C ₃ to C ₁₀ crushed alkyl group, cyclohexyl group, or phenyl group, and n is 2 to 3.

As a preferred embodiment of the present invention, the dispersant in the cement mortar composition may include a polycarboxylic acid-based dispersant.

In a preferred embodiment of the present invention, the strength enhancer in the cement mortar composition may include one or more selected from calcium carbonate powder, marl powder, kaolin powder, and maleated ethylene-propylene-diene copolymer.

In a preferred embodiment of the present invention, the maleated ethylene-propylene-diene compound includes 2 to 8 wt% of maleic anhydride, 15 to 25 wt% of ethylene, 30 to 40 wt% of propylene, and the balance of 100 wt% of the diene compound. It may be a copolymer obtained by copolymerizing a mixture containing.

As a preferred embodiment of the present invention, the diene compound used in the copolymerization of the maleated ethylene-propylene-diene compound may include a C ₂ to C ₅ straight-chain alkylene or a C ₃ to C ₆ branched alkylene. You can.

As a preferred embodiment of the present invention, the durability enhancer in the cement mortar composition may include one or more selected from cellulose fiber, propylene fiber, and glass fiber.

In a preferred embodiment of the present invention, the adhesion improver in the cement mortar composition may include 20 to 30% by weight of polymer mixed resin, 2 to 5% by weight of fluidity improver, and the remaining amount of 100% by weight of siloxane emulsion.

In a preferred embodiment of the present invention, the polymer mixed resin among the adhesion improver components includes acrylonitrile-butadiene-styrene, (C ₃ to C ₁₀ alkyl) methacrylate and vinyl acetate at a ratio of 1:0.2 to 0.5:0.5. It can be included at a weight ratio of ~ 0.7.

As a preferred embodiment of the present invention, the attachment aid in the cement mortar composition may include ethyl vinyl acetate, carboxylated polyethylene, and starch in a weight ratio of 1:0.1 to 0.4:0.1 to 0.2.

As a preferred embodiment of the present invention, the curing retardant in the cement mortar composition may include at least one selected from phenylphosphonic acid metal salt and glycerin.

As a preferred embodiment of the present invention, the plastering improver in the cement mortar composition may include a nonionic surfactant.

As a preferred embodiment of the present invention, the waterproofing agent in the cement mortar composition may include at least one selected from acrylic latex resin and water-dispersed SBR latex resin.

As a preferred embodiment of the present invention, the water repellent in the cement mortar composition may include at least one selected from fluorine-based water repellent and zinc stearate.

As a preferred embodiment of the present invention, the cement mortar of the present invention contains 30 to 40% by weight of mixed cement, 0.5 to 2.0% by weight of quick setting agent, 0.1 to 0.8% by weight of quick setting aid, 1.5 to 3.0% by weight of anti-shrinkage agent, and 0.1% by weight of dispersant. ~ 1.0% by weight, strength enhancer 2.5 ~ 5.0% by weight, durability enhancer 1.0 ~ 3.0% by weight, adhesion improver 1.0 ~ 4.0% by weight, adhesion aid 0.01 ~ 0.20% by weight, curing retardant 0.2 ~ 1.0% by weight, plastering improver 0.001 ~ It may include 0.050% by weight, 0.20 to 0.80% by weight of waterproofing agent, 0.20 to 1.00% by weight of water repellent, and the remaining amount of fine aggregate among 100% by weight.

Another object of the present invention is to provide an ultra-fast hardening lightweight repair reinforcement for a concrete structure containing the cement mortar described above, which includes 40 to 100 parts by weight of water based on 100 parts by weight of the ultra-fast hardening lightweight cement mortar.

In addition, another object of the present invention relates to a repair and reinforcement construction method for a concrete structure, which includes the first step of chipping and cleaning the damaged part of the concrete structure; Step 2: Prime the chipped and cleaned areas; Step 3 of applying the ultra-fast hardening lightweight repair reinforcement to the primer-treated area; and 4 steps of plastering and curing before mortar hardening.

The ultra-fast hardening lightweight repair reinforcement manufactured using the cement mortar of the present invention is lightweight and has excellent bonding and bonding holding power to concrete structures, has fast hardening, has a short gelation time, does not cause material separation, and has excellent compressive strength. Excellent mechanical properties such as

The effects of the present invention are not limited to those mentioned above, and effects not mentioned above will be clearly understood by those skilled in the art from the following description.

The numerical limit range described in the present invention includes all values within the starting and ending point ranges. For example, the range of "20℃ to 100℃" includes '20℃, 25℃, 30℃, 35℃, 40℃, Values 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C as well as 20°C to 40°C, 50°C to 70°C , 80℃ to 100℃, etc. is meant to include arbitrary values between integers that fit within the scope of the stated range. In addition, the range of "10 minutes to 100 minutes" is, for example, '10 minutes to 20 minutes, 20 minutes to 30 minutes, 30 minutes to 40 minutes, 40 minutes to 50 minutes, 60 minutes to 70 minutes, 70 minutes to 70 minutes.' All integers including 80 minutes, 80 minutes to 90 minutes, and 90 minutes to 100 minutes, as well as any integers between 20 minutes to 40 minutes, and 80 minutes to 100 minutes, fall within the categories of the ranges so stated. It means including.

In addition, in expressions such as “alkyl of C ₃ to C ₁₀ ,” “C ₃ ” and “ C ₁₀ ” refer to the number of carbon atoms.

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

The fast-setting lightweight cement mortar of the present invention includes mixed cement, fine aggregate, quick setting agent, quick setting aid, anti-shrinkage agent, dispersant, strength enhancer, durability enhancer, adhesion improver, adhesion aid, curing retardant, plastering improver, waterproofing agent and water repellent agent. .

Among the fast-hardening lightweight cement mortar compositions, the mixed cement includes one or more types selected from Portland cement, ultrafine cement, and alumina cement, and preferably includes one type of Portland cement, ultrafine particle cement, and alumina cement. , more preferably one type of Portland cement, ultrafine particle cement and alumina cement in a weight ratio of 1:0.20 to 0.35:0.05 to 0.15, and even more preferably in a weight ratio of 1:0.25 to 0.32:0.05 to 0.10.

The ultra-fine particle cement is manufactured by a cement firing method for the purpose of maintaining the initial workability of hydration and refining the cement particle size, and the ultra-fine particle cement is made by mixing gypsum and gypsum into clinker, a semi-finished product for low-heat cement (KS type 4 cement). /Or after adding 3 to 5% by weight of anhydrous gypsum, firstly, compression shear grinding is performed on rollers to a powder level of about 4,000 ㎠/g, and then secondly, powder concentration and swirl flow are determined in a high-performance powder separator. By adjusting the speed, cement made of ultra-fine particles with a powder degree in the range of 5,000 to 15,000 cm2/g, preferably 6,000 to 12,000 cm2/g, can be used.

Excellent early compressive strength can be achieved by using the ultrafine cement, and if the amount of ultrafine cement in the mixed cement is less than 0.20 weight ratio based on Portland cement, the effect of improving early compressive strength is minimal, and the effect of resisting ion penetration from the outside is minimal. may be insufficient, and if used in excess of 0.35 weight ratio, the flowability of the repair reinforcement may be poor and workability during concrete repair and reinforcement construction may be reduced, so it is recommended to use within the above range.

In addition, among the mixed cement components, the alumina cement is used together to increase the rapid hardening and chemical resistance of the repair reinforcement. When used at a weight ratio of less than 0.05 based on Portland cement, the amount used is too small, so its use increases the rapid hardening and There may be no increase in chemical resistance, and if used in excess of 0.15 weight ratio, the early compressive strength of the cured repair reinforcement may be low, and the economic feasibility of the grout material may decrease due to the high price, so it is recommended to use within the above range.

The amount of the mixed cement used in the fast-hardening lightweight cement mortar is 30 to 40% by weight, preferably 33 to 40% by weight, more preferably 33.0 to 38.5% by weight, based on 100% by weight of the cement mortar, and the mixed cement content is 30% by weight. If it is less than %, the physical properties of the repair reinforcement used in the cement mortar of the present invention may not satisfy the physical properties required as a repair reinforcement, and if it is used in excess of 40% by weight, the content of other compositions is relatively small to secure sufficient physical properties, fast hardening, etc. may not be secured.

Among the fast-hardening lightweight cement mortar compositions, the fine aggregate may be silica sand, and preferably, fine aggregate containing cenosphere and/or silica airgel may be used to lighten the cement mortar. As a preferred embodiment of the fine aggregate, the fine aggregate is 2 to 5% by weight of bottom ash, 5 to 8% by weight of blast furnace slag, 5 to 10% by weight of senosphere, 5 to 12% by weight of silica airgel, and the remainder, based on the total weight% of the fine aggregate. One containing a residual amount of silica sand can be used, preferably 3 to 4% by weight of bottom ash, 5.5 to 7.0% by weight of blast furnace slag, 6.0 to 7.5% by weight of cenosphere, 6.0 to 10.0% by weight of silica airgel, and the remaining amount of silica sand. You can use anything containing .

The silica airgel may be powdered silica airgel and/or granular silica airgel.

And, the content of fine aggregate in cement mortar is the remaining amount excluding other compositions of cement mortar out of 100% by weight.

In addition, the quick-setting agent in the cement mortar composition serves to improve constructability by increasing the curing speed of the cement mortar, and may include bauxite, calcium sulfoaluminate, quick-setting aid, anti-flow agent, rapid hardening agent, and setting aid. Preferably, 25 to 35% by weight of bauxite, 0.2 to 1.5% by weight of anti-flow agent, 8.0 to 12.0% by weight of fast setting supplement, 5.0 to 10.0% by weight of setting aid, and the remaining amount of calcium sulfoaluminate among the total weight%. It may include, more preferably, 26.2 to 30.5% by weight of bauxite, 0.4 to 1.2% by weight of anti-flow agent, 9.5 to 11.0% by weight of fast setting supplement, 7.0 to 9.0% by weight of setting aid, and the remaining amount of the total weight%. May contain calcium sulfoaluminate. Among the components of the quick-setting agent, bauxite, together with calcium sulfoaluminate, plays a role in reducing the gel time of cement mortar (or repair reinforcement) and increasing the curing speed, and preferably has a powder degree of 5,000 cm ² /g or more. It is preferable to use bauxite with a powder degree of 6,000 to 8,000 cm ² /g in terms of miscibility with other mortar compositions. Among the components of rapid setting additives, the flow prevention agent plays a role in controlling the viscosity of the rapid setting additive, and it is recommended to use mecellose, a flow prevention agent used in rapid setting additives. In addition, it is better to use burnt lime as the fast setting additive in the composition of the quick setting material, and it is better to use soda ash (Na ₂ CO ₃ ) as the setting additive.

In addition, the content of the quick-setting agent in the cement mortar is 0.5 to 2.0% by weight, preferably 0.6 to 1.5% by weight, and more preferably 0.7 to 1.3% by weight. If the quicksetting agent content is 0.5% by weight, the gel of the cement mortar Because the time and curing speed are prolonged, the rapid hardening of cement mortar (or repair reinforcement) is lost. If it exceeds 2.0% by weight, problems with micro cracks occurring in the hardened repair reinforcement may occur due to excessive use, so use within the above range. It's good to do it.

In addition, the quick-setting aid in the fast-setting lightweight cement mortar composition serves to increase the miscibility of the quick-setting agent with other cement mortar compositions and improve the bonding and adhesion of the cement mortar. It is recommended to use (Na ₂ SO ₄ ), and the content of the quick-setting agent is 0.01 to 0.8% by weight, preferably 0.03 to 0.20% by weight, more preferably 0.04 to 0.10% by weight, based on the total weight% of the cement mortar. It is appropriate, and if the content of the quick-setting aid is less than 0.01% by weight, the amount used may be too small and the effect of use may be minimal, and if it is used in excess of 0.8% by weight, the miscibility of the cement mortar composition and the quick-setting material may be impaired. Therefore, it is recommended to use it within the above range.

Next, the anti-shrinkage agent in the cement mortar composition plays a role in preventing the fast-hardening cement mortar (or repair reinforcement) from shrinking significantly while curing and hardening quickly. As an anti-shrinkage agent, it is purchased commercially for use in fast-setting cement mortar. Any available material can be used, and preferably a compound represented by the following formula (1) can be used as an anti-shrinkage agent.

[Formula 1]

(RCH ₂ CH ₂ CH=CH) _n SiO

In Formula 1, R is a C ₃ -C ₁₀ crushed alkyl group, cyclohexyl group, or phenyl group, and preferably R is a C ₅ -C ₈ ground alkyl group. And, n in Formula 1 is 2 to 3, and preferably n is 2.

In addition, the content of the anti-shrinkage agent in the cement mortar is 1.5 to 3.0% by weight, preferably 1.6 to 2.6% by weight, and more preferably 1.8 to 2.3% by weight. If the anti-shrinkage agent content is less than 1.5% by weight, the anti-shrinkage effect is insufficient. If it exceeds 3.0% by weight, miscibility between cement mortar compositions may be impaired and curing may be delayed, so it is appropriate to use it within the above range.

Next, in the fast-hardening lightweight cement mortar composition, the dispersant serves to increase miscibility with mixed cement, adhesion improvers, adhesion aids, etc., and to prevent the mortar composition from agglomerating. The dispersant includes a polycarboxylic acid-based dispersant. Polycarboxylic acid-based dispersants that can be used and are commercialized include Melflex 2651, PC1031, and PC-WP500P.

And, the amount used is 0.1 to 1.0% by weight, preferably 0.2 to 0.9% by weight, and more preferably 0.3 to 0.8% by weight, based on the total weight% of the cement mortar. If the content is less than 0.1% by weight, the cement mortar compositions agglomerate. Deterioration of the physical properties of the repair reinforcement may occur, and if used in excess of 1.0% by weight, the adhesion and adhesion of the repair reinforcement may decrease, so it is recommended to use within the above range.

Next, the strength enhancer in the fast-setting lightweight cement mortar composition may include one or more selected from calcium carbonate powder, marl powder, kaolin powder, and maleated ethylene-propylene-diene copolymer, preferably calcium carbonate. It may contain one or more types selected from powder, kaolin powder, and maleated ethylene-propylene-diene copolymer, and more preferably calcium carbonate powder, kaolin powder, and maleated ethylene-propylene-diene copolymer at a ratio of 1:0.1 ~ It can be included in a weight ratio of 0.2:0.3 to 0.4.

Among the strength enhancers, the maleated ethylene-propylene-diene copolymer is a rubber-based compound, comprising 2 to 8% by weight of maleic anhydride, 15 to 25% by weight of ethylene, 30 to 40% by weight of propylene, and the balance of 100% by weight of the diene compound. It is a copolymer obtained by copolymerizing a mixture containing 4.5 to 7.5% by weight of maleic anhydride, 20.0 to 23.0% by weight of ethylene, 34.0 to 38.0% by weight of propylene, and a remainder of 100% by weight of a diene compound. It is a combination.

In addition, the diene compound may include C ₂ - C ₅ straight-chain alkylene or C ₃ - C ₆ branched alkylene, and more preferably C ₄ - C ₅ branched alkylene.

In addition, the content of the strength enhancer in the cement mortar is appropriate to include 2.5 to 5.0% by weight, preferably 3.2 to 5.0% by weight, and more preferably 3.5 to 4.5% by weight, and the content is less than 2.5% by weight. The effect of improving back impact resistance, compressive strength, etc. may be insufficient, and if it exceeds 5.0% by weight, the adhesion of cement mortar may decrease, so it is appropriate to use it within the above range.

Next, the durability enhancer in the fast-hardening lightweight cement mortar composition serves to improve the mechanical properties of the cured mortar, and may include one or more selected from cellulose fiber, propylene fiber, and glass fiber, preferably cellulose fiber. and propylene fibers. Additionally, the propylene fiber may be a monofilament polypropylene fiber. In addition, the content of the durability enhancer may include 1.0 to 3.0% by weight, preferably 1.0 to 2.8% by weight, and more preferably 1.0 to 1.6% by weight, based on the total weight% of the cement mortar. At this time, if the durability enhancer content is less than 1.0% by weight, there may be a problem in which sufficient durability improvement effect cannot be seen. If it is used in excess of 3.0% by weight, spraying of repair reinforcement material made of cement mortar may be difficult due to agglomeration. Since this may not be possible, it is advisable to use it within the above range.

Next, the adhesion improver in the fast-setting lightweight cement mortar composition serves to increase the adhesion of the fast-setting cement mortar to the concrete structure, and includes a siloxane emulsion, a polymer mixed resin, and a fluidity improver, and preferably a polymer mixed resin. It may include 20 to 30% by weight, 2 to 5% by weight of fluidity improver, and the remaining amount of 100% by weight of siloxane emulsion, more preferably 24.0 to 28.0% by weight of polymer mixed resin, 2.0 to 3.5% by weight of fluidity enhancer, and The remaining amount of 100% by weight may include siloxane emulsion.

Among the adhesion improver components, the polymer mixed resin may include acrylonitrile-butadiene-styrene, (C ₃ to C ₁₀ alkyl) methacrylate and vinyl acetate, preferably acrylonitrile-butadiene-styrene. , (C ₃ ~ C ₁₀ alkyl) methacrylate and vinyl acetate may be included in a weight ratio of 1: 0.2 ~ 0.5: 0.5 ~ 0.7, acrylonitrile-butadiene-styrene, (C ₃ ~ C ₄ alkyl) ) Methacrylate and vinyl acetate may be included in a weight ratio of 1:0.25 to 0.30:0.50 to 0.55.

Among the adhesion improver components, the siloxane emulsion contains 30 to 40% by weight of siloxane-based compound, 15 to 20% by weight of acrylic copolymer resin, 5 to 15% by weight of ethoxylate secondary alcohol, 0.2 to 1.0% by weight of surfactant, and the remaining amount. It is prepared by mixing and hydrolyzing % by weight of water, preferably 32 to 38% by weight of siloxane-based compound, 15 to 18% by weight of acrylic copolymer resin, 6 to 12% by weight of ethoxylate secondary alcohol, and interface. It is prepared by mixing and hydrolyzing 0.4 to 0.8% by weight of activator and the remaining weight% of water.

In addition, among the siloxane emulsion components, the siloxane-based compound represented by the following formula (2) may be used.

[Formula 2]

In Formula 2, R ¹ is a hydrogen atom or a straight-chain alkyl group of C ₁ to C ₃ , and is preferably a hydrogen atom. And, R ² in Formula 1 is a hydrogen atom, -COOH, -COOCH ₃ or a straight-chain alkyl group of C ₁ to C ₃ , preferably R ² is -COOH or -COOCH ₃ , and more preferably -COOH. . And, R ³ in Formula 1 is a hydrogen atom, a straight-chain alkyl group of C ₁ to C ₃ , -CH ₂ COOH or -CH ₂ COOCH ₃ , and preferably, R ³ is a straight-chain alkyl group of C ₁ to C ₃ , - CH ₂ COOH or -CH ₂ COOCH ₃ , and more preferably R ³ is -CH ₂ COOH. And, m in Formula 1 is an integer of 2 to 10.

Among the siloxane emulsion components, the acrylic copolymer resin includes 50 to 60% by weight of hydroxyl (alkyl of C1 to C3) acrylate monomer, 15 to 20% by weight of amine-containing aromatic vinyl monomer represented by the following formula (3), and 0.01 to 0.20% by weight of polymerization initiator. It is a copolymer obtained by copolymerizing a mixed solution containing % and solvent. The acrylic copolymer resin serves to increase the adhesion and chemical resistance of siloxane-based compounds, and has a weight average molecular weight (Mw) of 10,000 g/mol to 50,000 g/mol, preferably a weight average molecular weight of 12,000 g/mol to 12,000 g/mol. It is preferably 45,000 g/mol, more preferably 15,000 to 35,000 g/mol. If the weight average molecular weight is 10,000 g/mol, the effect of improving adhesion may be minimal, and if it exceeds 50,000 g/mol, chemical resistance and other Since the problem of maintaining bonding with components may actually decrease, it is better to use one having a weight average molecular weight within the above range.

[Formula 3]

R ¹ in Formula 3 is a hydrogen atom or an alkyl group of C ₁ to C ₃ , a hydrogen atom or a methyl group, and more preferably a hydrogen atom. R ² in Formula 2 is a C ₁ to C ₃ alkylene group or -O-, preferably a propylene group or -O-, and more preferably -O-. Each of R ³ and R ⁴ in Formula 2 is independently a hydrogen atom, a C ₁ to C ₅ straight-chain alkyl group, or a C ₃ to C ₇ branched alkyl group, preferably a hydrogen atom or a C ₁ to C ₃ straight-chain alkyl group. It is an alkyl group, and more preferably, it is a straight-chain alkyl group of C ₁ to C ₂ .

The polymerization initiator used to prepare the acrylic copolymer resin may include at least one selected from C ₁ to C ₁₀ alkyl lithium, sodium alkoxide, potassium alkoxide, and lithium sulfonate, preferably C ₂ to C It may contain ₅ alkyl lithium or lithium sulfonate. The solvent used to prepare the acrylic copolymer resin may include one or more selected from n-pentane, n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene, and xylene, and is preferably n-hexane. , n-heptane, and cyclohexane.

In addition, the surfactant among the siloxane emulsion components may include one or more selected from C ₈ to C ₁₈ fatty alcohol ethoxylate, block copolymer of ethylene oxide and propylene oxide, and C ₈ to C ₁₈ alkyl polyglycoside. there is.

In addition, the content of the adhesion improver in the cement mortar can be 1.0 to 4.0 wt%, preferably 1.8 to 3.8 wt%, and more preferably 1.8 to 3.0 wt%. If the adhesion improver content is less than 1.0 wt%, The effect of improving adhesion may be minimal, and if used in excess of 4.0% by weight, the viscosity may be too high after mixing with cement mortar and water, resulting in poor constructability, so it is appropriate to use within the above range.

Next, the adhesion aid in the fast-hardening lightweight cement mortar composition serves to increase the adhesion of the adhesion improver to the concrete structure, and is one or more selected from ethyl vinyl acetate, carboxylated polyethylene, and starch. It may contain, preferably ethyl vinyl acetate, carboxylated polyethylene, and starch in a weight ratio of 1:0.1 to 0.4:0.1 to 0.2. In addition, the content of the adhesion aid in the cement mortar may include 0.01 to 0.20% by weight, preferably 0.01 to 0.12% by weight, and more preferably 0.01 to 0.10% by weight. At this time, if the content of the adhesion aid is less than 0.01% by weight, the effect of adhesion due to its use may be minimal, and even if it is used in excess of 0.20% by weight, there may be no effect of increasing adhesion, so it is recommended to use it within the above range.

Next, the curing retardant in the fast-setting lightweight cement mortar composition is used to delay rapid hardening to ensure workability for a certain period of time, and includes sugars such as glucose, glucose, textrin, and dextran, and glue. Acids such as conic acid, malic acid, citric acid, citric acid or their salts, aminocarboxylic acid or its salts, phosphonic acid or its derivatives, polyhydric alcohols such as glycerin, etc. can be used, preferably phenylphosphonic acid metal salt and It may contain one or more types selected from glycerin, and more preferably, phenylphosphonic acid metal salt and glycerin may be mixed in a weight ratio of 1:3 to 4.

In addition, the amount of curing retardant used may include 0.2 to 1.0% by weight, preferably 0.3 to 0.7% by weight, and more preferably 0.3 to 0.5% by weight, based on the total weight% of the cement mortar. At this time, if the curing retardant content is less than 0.2% by weight, the effect of delaying the curing of cement mortar may be insufficient, which may lead to problems with poor construction workability using the water reinforcement agent. If the content exceeds 1.0% by weight, excessive use may result in cement damage. Since the rapid hardening of the mortar may be lost, it is appropriate to use it within the above range.

Next, the plastering improver in the composition of the fast-setting lightweight cement mortar plays a role in preventing the generation of bubbles in the cured mortar, and may include a nonionic surfactant, preferably a C ₈ to C ₁₈ fatty alcohol ethoxyl. A non-ionic surfactant containing at least one selected from the group consisting of latex, block copolymers of ethylene oxide and propylene oxide, and C ₈ to C ₁₈ alkyl polyglycosides may be used. In addition, the amount of the plaster improvement agent may be 0.001 to 0.050% by weight, preferably 0.001 to 0.010% by weight, based on the total weight% of the cement mortar.

Next, the waterproofing agent in the fast-setting lightweight cement mortar composition may include at least one selected from acrylic latex resin and water-dispersed SBR latex resin, and preferably acrylic latex resin may be used. In addition, the amount of the waterproofing agent used may include 0.20 to 0.80% by weight of the total weight% of the cement mortar, preferably 0.25 to 0.60% by weight, and more preferably 0.30 to 0.50% by weight. At this time, if the waterproofing agent content is less than 0.20% by weight, the amount used is too small and the waterproofing effect may be insufficient, and if it exceeds 0.80% by weight, the miscibility of water and cement mortar when manufacturing repair reinforcement is so poor that workability may be reduced. .

Next, the water repellent agent in the fast-hardening lightweight cement mortar composition plays a role in preventing deterioration of the structure caused by water penetrating into the concrete structure (waterproofing effect) and providing an anti-fungal effect. The water repellent may include at least one selected from fluorine-based water repellent and zinc stearate, and preferably includes zinc stearate. Additionally, the water repellent may be used in an amount of 0.20 to 1.00 wt%, preferably 0.30 to 0.90 wt%, and more preferably 0.40 to 0.80 wt% of the total weight of the cement mortar. At this time, if the water repellent content is less than 0.20% by weight, there may be a problem of insufficient water repellent effect due to its use, and it is uneconomical to use it in excess of 1.00% by weight, and it is better to use it within the above range.

In addition, the fast-hardening lightweight cement mortar of the present invention described above may further include other additives such as fillers, crack reducers, air entrainers, environmental fillers, rust inhibitors, and anti-flow agents.

Hereinafter, a repair and reinforcement construction method for a concrete structure using a repair reinforcement material containing the fast-hardening lightweight cement mortar of the present invention described above will be described.

Step 1: chipping and cleaning damaged areas of concrete structures; Step 2: Prime the chipped and cleaned areas; Step 3 of applying the ultra-fast hardening lightweight repair reinforcement to the primer-treated area; and 4 steps of plastering and curing before mortar hardening.

In the first stage, the process of checking and investigating the area subject to repair may be performed in advance of chipping in order to confirm the degree of repair and reinforcement construction and the exact construction area of the concrete structure where cracks or concrete deterioration occurred. there is.

And, step 1 is the step of chipping the area to be repaired and then performing high-pressure water washing of the chipped area. At this time, chipping and cleaning methods can be performed through common methods in the art. At this time, if there is a reinforcing bar exposed from the concrete structure after chipping and washing, the process of removing rust from the reinforcing bar can be performed by a general method performed in the art.

In addition, in the first step, the chipped and cleaned area may be further treated with a rust preventive agent. The rust preventive agent may be a general rust preventive agent used in the art, but a preferred example is a one-component rust preventive agent containing epoxy resin, ordinary Portland cement, silicone oil, nitrite, sodium gluconate, water reducing agent, and water. .

Next, in the construction method of the present invention, the second step is to perform primer treatment to improve the adhesion of the three-step fast-hardening repair and reinforcement mortar to the concrete structure, and the primer in the second step is a primer used in the art. A general primer for cement construction can be used.

Next, in the construction method of the present invention, step 3 is a process of preparing a repair reinforcement by mixing the fast-hardening lightweight cement mortar of the present invention described above with water on the primer-treated area and then applying it. The application method is as follows. A general method used in the industry can be used, for example, the fast-hardening lightweight cement mortar can be sprayed and applied on top of the second-stage primer. At this time, the water reinforcement material can be prepared by mixing and stirring 40 to 100 parts by weight of water, preferably 45 to 80 parts by weight, based on 100 parts by weight of the cement mortar.

In addition, in the construction method of the present invention, in the fourth step, the repair reinforcement material applied in the third step is plastered and then cured to repair and strengthen the concrete structure.

After completion of construction, the cured repair reinforcement is tested for adhesion and if it passes the test, construction can be completed.

When measured in accordance with KS F 4716, the cured product (cured) of the cured repair reinforcement (or cement mortar) of the present invention has an adhesion strength of 1.60 kgf/cm2 or more on the 7th day and an adhesion strength of 1.70 kgf/cm2 on the 28th day. The above can be satisfied, and preferably, the adhesion strength on the 7th day is 1.60 ~ 1.80 kgf / ㎠ and the adhesion strength on the 28th day is 1.75 ~ 1.95 kgf / ㎠.

When measured in accordance with KS F 2476, the hardened (cured) repair reinforcement material (or cement mortar) of the present invention has a compressive strength of 32.0 ~ 37.5 kgf / ㎠ on the 7th day and a compressive strength of 50.0 ~ 56.5 kgf on the 28th day. /cm2, and preferably satisfies the 7th day compressive strength of 32.5 ~ 37.0 kgf/cm2 and the 28th day compressive strength of 50.0 ~ 56.0 kgf/cm2.

In addition, the hardened (cured) repair reinforcement material (or cement mortar) of the present invention has a bending strength of 7.70 ~ 9.50 kgf / cm2 on the 7th day and a bending strength of 9.50 ~ 11.00 kgf on the 28th day when measured in accordance with KS F 2476. /cm2, preferably 7.90 ~ 9.00 kgf/cm2 on the 7th day and 9.70 ~ 10.70 kgf/cm2 on the 28th day, more preferably 7.90 ~ 8.80 kgf/cm2 on the 7th day and 7.90 ~ 8.80 kgf/cm2 on the 28th day. A bending strength of 9.70 to 10.50 kgf/cm2 can be satisfied.

The present invention will be described in detail through preferred embodiments, and the following examples are illustrative of the present invention, and the present application is not limited by the following examples.

[Example]

Preparation Example 1: Preparation of adhesion improving agent

An adhesion improver was prepared by mixing and stirring 24.8% by weight of polymer mixed resin, 3.0% by weight of fluidity improver, and the remaining amount of siloxane emulsion of 100% by weight.

The polymer mixed resin includes acrylonitrile-butadiene-styrene, propyl methacrylate, and vinyl acetate in a weight ratio of 1:0.26:0.53.

In addition, the siloxane emulsion contains 34.5% by weight of a siloxane-based compound represented by the following formula 2-1, 18.3% by weight of acrylic copolymer resin (Mw = 23,000 to 30,000 g/mol), 8.3% by weight of ethoxylate secondary alcohol, It was prepared by mixing 0.7% by weight of surfactant and the remaining weight% of water and then hydrolyzing it.

[Formula 2-1]

In Formula 2-1, R ¹ is a hydrogen atom, R ² is -COOH, R ³ is -CH ₂ COOH, and m is 6.

In addition, the acrylic copolymer resin contains 55.2% by weight of hydroxyl (alkyl of C ₂ )acrylate monomer, 16.9% by weight of amine-containing aromatic vinyl monomer represented by the following Chemical Formula 3-1, and 0.03% by weight of polymerization initiator (t-butyllithium). It is a copolymer obtained by copolymerizing a mixture containing % by weight and cyclohexane (solvent).

[Formula 3-1]

In Formula 3-1, R ¹ is a hydrogen atom, R ² is -O-, and each of R ³ and R ⁴ is a methyl group.

Comparison preparation example 1

Without using the polymer mixed resin of Preparation Example 1, an adhesion improver was prepared by mixing and stirring 10.0 wt% of the fluidity improver and 90.0 wt% of the siloxane emulsion. At this time, the same fluidity improver and silonic acid emulsion as in Preparation Example 1 were used.

Example 1: Preparation of ultra-fast hardening lightweight cement mortar

(1) Manufacturing of mixed cement

Mixed cement was prepared by mixing type 1 Portland cement, ultrafine cement, and alumina cement at a weight ratio of 1:0.29 to 0.32:0.07.

The ultra-fine particle cement was made by adding 4.8% by weight of gypsum to clinker, a semi-finished product for low-heat cement (KS type 4 cement), and then grinding it through compression shear on a roller to a powder level of about 4,000 cm2/g. Next, the powder concentration and swirl flow speed were adjusted in a second high-performance powder separator to produce powder in the range of about 8,000 to 10,000 cm2/g.

(2) Manufacture of fine aggregate

Fine aggregate was prepared by mixing 3.4% by weight of bottom ash, 6.2% by weight of blast furnace slag, 6.6% by weight of cenospheres, 7.8% by weight of particulate silica airgel, and the remaining amount of silica sand.

(3) Manufacture of quick-setting lumber

27.9% by weight of bauxite with a fineness of 6,800 ~ 7,000 cm ² /g, 0.7% by weight of mecellose as an anti-flow agent, 10.1% by weight of burnt lime as a fast-hardening agent, and soda ash (Na ₂ CO _{3 )} as a setting aid. ) Rapid setting material was prepared by mixing 7.3% by weight and the remaining amount of calcium sulfoaluminate among the total weight%.

(4) Manufacture of strength enhancers

A strength enhancer was prepared by mixing calcium carbonate powder, kaolin powder, and maleated ethylene-propylene-diene copolymer in a weight ratio of 1:0.16:0.33.

The maleated ethylene-propylene-diene copolymer is a rubber-based compound, which is a copolymerization of a mixture containing 5.3% by weight of maleic anhydride, 20.8% by weight of ethylene, 35.5% by weight of propylene, and the balance of 3-methylene-butene among 100% by weight. It is a combination.

(5) Manufacturing of attachment aids

An attachment aid was prepared by mixing ethyl vinyl acetate, carboxylated polyethylene, and starch in a weight ratio of 1:0.26:0.13.

(6) Manufacturing of cement mortar

34.02% by weight of the mixed cement, 1.03% by weight of the quick setting material, 0.05% by weight of Na ₂ SO ₄ as a quick setting aid, 2.0% by weight of a compound represented by the following formula 1-1 as an anti-shrinkage agent, and polycarboxylic acid as a dispersant. 0.50% by weight of dispersant (product name: PC-WP500P), 4.11% by weight of the strength enhancer, 1.00% by weight of monofilament polypropylene fiber as a durability enhancer, 2.05% by weight of the adhesion improver prepared in Preparation Example 1, 0.01% by weight of the above adhesion aid, 0.002% by weight of (C ₁₂ ~ C ₁₄ alkyl) polyglycoside as a plastering improver, 0.41% by weight of acrylic latex resin as a water repellent, 0.50% by weight of zinc stearate as a water repellent, and the remaining amount of the fine aggregate of 100% by weight are mixed and stirred. Cement mortar was manufactured.

[Formula 1-1]

(RCH ₂ CH ₂ CH=CH) _n SiO

In Formula 1-1, R is 4-methylene (=CH ₂ )-pentyl group, and n is 2.

Examples 2 to 6 and Comparative Examples 1 to 7

Cement mortar was prepared using the same composition as in Example 1, but Examples 2 to 6 and Comparative Examples 1 to 7 were performed with different composition contents as shown in Table 1 below. However, in Comparative Example 3, cement mortar was manufactured using the adhesion improver prepared in Comparative Preparation Example 1 instead of the adhesion improver prepared in Preparation Example 1.

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 mixed cement 34.02 34.02 34.02 34.02 30.5 38.5 quick payment 1.03 1.03 1.03 1.03 1.03 1.03 Quick fixing aid 0.05 0.05 0.05 0.05 0.05 0.05 anti-shrinkage agent 2.0 2.0 1.5 2.6 2.0 2.0 dispersant 0.50 0.50 0.50 0.50 0.50 0.50 strength enhancer 4.11 4.11 4.11 4.11 4.11 4.11 Durability enhancer 1.00 1.00 1.00 1.00 1.00 1.00 Adhesion improver 2.05 3.80 2.05 2.05 2.05 2.05 Attachment aid 0.01 0.02 0.01 0.01 0.01 0.01 cosmetic improvement agent 0.002 0.002 0.002 0.002 0.002 0.002 waterproofing agent 0.41 0.41 0.41 0.41 0.41 0.41 water repellent 0.05 0.05 0.05 0.05 0.05 0.05 fine aggregate Remaining amount of 100% by weight

division Comparative Example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative Example 5 Comparative Example 6 Comparative example 7 mixed cement 35.07 34.02 34.02 34.02 34.02 28.7 42.3 quick payment 1.03 1.03 1.03 1.03 1.03 1.03 1.03 Quick fixing aid 0.05 0.05 0.05 0.05 0.05 0.05 0.05 anti-shrinkage agent 2.0 2.0 2.0 0.8 3.5 2.0 2.0 dispersant 0.50 0.50 0.50 0.50 0.50 0.50 0.50 strength enhancer 4.11 4.11 4.11 4.11 4.11 4.11 4.11 Durability enhancer 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Adhesion improver - 4.50 2.05
(comparison
Preparation example 1) 2.05 2.05 2.05 2.05 Attachment aid 0.01 0.02 0.01 0.01 0.01 0.01 0.01 cosmetic improvement agent 0.002 0.002 0.002 0.002 0.002 0.002 0.002 waterproofing agent 0.41 0.41 0.41 0.41 0.41 0.41 0.41 water repellent 0.05 0.05 0.05 0.05 0.05 0.05 0.05 fine aggregate Remaining amount of 100% by weight

Experimental Example 1: Measurement of physical properties of mortar 1

The compressive and flexural strength of the hardened mortar was evaluated in accordance with KS F 2476, “Strength Test Method for Polymer Cement Mortar,” and the adhesive strength was evaluated in accordance with KS F 4716, “Strength Test Method for Polymer Cement Mortar.” The results are shown in Table 3.

And the specimen was manufactured with a repair reinforcement prepared by mixing 68 parts by weight of water with 100 parts by weight of the cement mortar prepared in Examples and Comparative Examples.

division Unit volume weight
(kg/㎥) compressive strength
(kgf/㎠) Bending strength
(kgf/㎠) Adhesion strength
(kgf/㎠) 7 days 28th 7 days 28th 7 days 28th Example 1 1.87 34.7 53.4 8.22 9.98 1.69 1.86 Example 2 1.85 34.6 53.8 8.20 10.05 1.75 1.91 Example 3 1.89 34.5 54.2 8.17 9.82 1.65 1.80 Example 4 1.85 35.0 52.5 8.24 10.18 1.71 1.90 Example 5 1.80 32.8 50.4 7.99 9.78 1.60 1.78 Example 6 1.94 35.8 55.6 8.40 10.25 1.72 1.92 Comparative Example 1 1.91 34.9 54.5 8.33 10.10 0.88 1.26 Comparative Example 2 1.87 31.2 50.9 7.95 9.28 1.78 1.93 Comparative Example 3 1.87 34.5 53.2 8.23 9.97 1.20 1.32 Comparative Example 4 1.90 35.2 51.6 8.31 9.57 1.61 1.74 Comparative Example 5 1.83 32.4 50.1 8.03 9.53 1.70 1.89 Comparative Example 6 1.76 30.2 47.9 7.76 8.94 1.56 1.65 Comparative Example 7 2.04 35.2 55.7 8.28 10.04 1.70 1.89

In the case of Comparative Example 1 in which no adhesion improver was used, compared to Examples 1 to 6 and other comparative examples, there was a problem of a significant lack of adhesion strength even though the amount of cement was greater. In the case of Comparative Example 2, in which more than 4% by weight of the adhesion improver was used, the adhesion strength was somewhat higher compared to Examples 1 and 2, but there was no significant increase in adhesion strength, and the compressive strength and bending strength were relatively low. There was a tendency to decrease, which is believed to be because when mixing cement mortar with water and manufacturing it as a repair reinforcement material, the viscosity was too high, causing a problem of poor miscibility between materials, and the viscosity was too high, so constructability was also judged to be poor. .

In addition, in the case of Comparative Example 3, which used the adhesion improvement agent of Comparative Preparation Example 1 rather than Preparation Example 1, there was a problem that the effect of improving adhesion strength was relatively poor when compared with Examples 1 to 6.

In addition, in the case of Comparative Example 4, in which the anti-shrinkage agent was used in an amount of less than 1.5% by weight, the initial compressive strength and initial flexural strength were excellent compared to Examples 1 and 3, but the compressive strength and flexural strength after 28 days actually decreased. There was a problem, and this is believed to be because the cured material of the repair reinforcement material was not effective in delaying or preventing shrinkage. In addition, in the case of Comparative Example 5, in which more than 3% by weight of the anti-shrinkage agent was used, compared to Examples 1 and 4, the adhesion strength was adequate, but there was a problem with the compressive strength and bending strength being somewhat low, which was a problem compared to Examples 1 and Example 4. This is believed to be because the miscibility between compositions in the repair reinforcement (cement mortar) is relatively poor compared to Example 4.

In addition, in the case of Comparative Example 6, where the mixed cement content was less than 30% by weight, compared to Examples 1 and 5, not only the compressive strength and bending strength, but also the adhesive strength was significantly reduced, and the mixed cement content was 40% by weight. In the case of Comparative Example 7, which was used in excess of %, compared to Examples 1 and 6, the increase in compressive strength and bending strength was slight, but the adhesive strength was somewhat lower, and the unit volume weight was increased, which lowered the tendency. There was.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited thereto, and can be implemented with various modifications within the technical scope of the present invention, which also fall within the scope of the appended patent claims. It is natural.

The repair reinforcement material using the cement mortar of the present invention has excellent lightweight properties and excellent mechanical properties and adhesion, and is used for various concrete structures such as deteriorated or corroded concrete structures, such as tunnels, bridges, sewer culverts, and roads. It can be applied to repair and reinforcement construction.

Claims (10)

Contains mixed cement, fine aggregate, quick setting agent, quick setting aid, anti-shrinkage agent, dispersant, strength enhancer, durability enhancer, adhesion improver, adhesion aid, curing retardant, plastering improver, waterproofing agent and water repellent,
The quick setting agent includes 25 to 35% by weight of bauxite, 0.2 to 1.5% by weight of anti-flow agent, 8.0 to 12.0% by weight of fast setting additive, 5.0 to 10.0% by weight of setting aid, and the remaining amount of calcium sulfoaluminate among the total weight%. do,
The quick setting aid includes networt (Na ₂ SO ₄ ),
Ultra-fast hardening lightweight cement mortar with improved adhesion, characterized in that the anti-shrinkage agent includes a compound represented by the following formula (1) ;
[Formula 1]
(RCH ₂ CH ₂ CH=CH) _n SiO
In Formula 1, R is a C ₃ to C ₁₀ crushed alkyl group, cyclohexyl group, or phenyl group, and n is 2 to 3.
The method of claim 1, wherein the mixed cement includes one type of Portland cement, ultrafine cement, and alumina cement in a weight ratio of 1:0.20 to 0.35:0.05 to 0.15,
The fine aggregate is an ultra-fast hardening lightweight cement mortar with improved adhesion, characterized in that it includes one or more selected from silica sand, bottom ash, blast furnace slag, cenosphere, and silica airgel.
delete The method of claim 1, wherein the dispersant includes a polycarboxylic acid-based dispersant,
The strength enhancer includes at least one selected from calcium carbonate powder, marl powder, kaolin powder, and maleated ethylene-propylene-diene copolymer,
The maleated ethylene-propylene-diene compound is a copolymer obtained by copolymerizing a mixture containing 2 to 8 wt% of maleic anhydride, 15 to 25 wt% of ethylene, 30 to 40 wt% of propylene, and the balance of 100 wt% of the diene compound. and
The diene compound is a super-fast hardening lightweight cement mortar with improved adhesion, characterized in that it contains straight-chain alkylene of C ₂ to C ₅ or pulverized alkylene of C ₃ to C ₆ .
The method of claim 1, wherein the durability enhancer includes at least one selected from cellulose fiber, propylene fiber, and glass fiber,
The adhesion improver includes 20 to 30% by weight of polymer mixed resin, 2 to 5% by weight of fluidity improver, and the remaining amount of siloxane emulsion of 100% by weight,
The polymer mixed resin has adhesion, characterized in that it contains acrylonitrile-butadiene-styrene, (C ₃ ~ C ₁₀ alkyl) methacrylate, and vinyl acetate in a weight ratio of 1: 0.2 ~ 0.5: 0.5 ~ 0.7. Improved rapid hardening lightweight cement mortar.
The method of claim 1, wherein the attachment aid includes ethyl vinyl acetate, carboxylated polyethylene, and starch in a weight ratio of 1:0.1 to 0.4:0.1 to 0.2,
The curing retardant includes at least one selected from phenylphosphonic acid metal salt and glycerin,
The plastering improver is an ultra-fast hardening lightweight cement mortar with improved adhesion, characterized in that it contains a non-ionic surfactant.
The method of claim 1, wherein the waterproofing agent includes at least one selected from acrylic latex and water-dispersed SBR latex,
The water repellent is an ultra-fast hardening lightweight cement mortar with improved adhesion, characterized in that it contains at least one selected from a fluorine-based water repellent and zinc stearate.
The method of claim 1, comprising: 30 to 40% by weight of mixed cement, 0.5 to 2.0% by weight of quick-setting agent, 0.1 to 0.8% by weight of quicksetting aid, 1.5 to 3.0% by weight of anti-shrinkage agent, 0.1 to 1.0% by weight of dispersant, and 2.5 to 5.0% by weight of strength enhancer. Weight %, durability enhancer 1.0 ~ 3.0 wt%, adhesion improver 1.0 ~ 4.0 wt%, adhesion aid 0.01 ~ 0.20 wt%, curing retardant 0.2 ~ 1.0 wt%, plastering improver 0.001 ~ 0.050 wt%, waterproofing agent 0.20 ~ 0.80 wt% , Ultra-fast hardening lightweight cement mortar with improved adhesion, characterized in that it contains 0.20 to 1.00% by weight of water repellent and the remaining amount of fine aggregate among 100% by weight.
Ultra-fast hardening lightweight repair of a concrete structure, characterized in that it contains 40 to 100 parts by weight of water per 100 parts by weight of the quick-hardening lightweight cement mortar of any one of claims 1, 2, and 4 to 8. reinforcement.
Step 1: chipping and cleaning damaged areas of concrete structures;
Step 2: Prime the chipped and cleaned areas;
Step 3 of applying the ultra-fast hardening lightweight repair reinforcement of paragraph 9 to the primer-treated area; and
A repair and reinforcement construction method for concrete structures characterized by performing a process including four steps of plastering and curing before mortar hardening.