KR102338230B1 - Non-shirinkage type polymer modified mortar composition and construction method for repairing and restoring the surface of concrete structures using the same - Google Patents

Abstract

The present invention relates to a non-shrinkage type polymer modified mortar composition and a construction method for repairing and restoring surfaces of concrete structures using the same, to provide excellent physical strength and durability by suppressing cracks in the deteriorated cross section of concrete structures. The composition includes 5 to 90 wt% of fine aggregate, 5 to 90 wt% of a shrinkage-reducing binder, 0.5 to 25 wt% of a polymer modifier, and 1 to 35 wt% of water.

Description

Non-shrinkage type polymer modified mortar composition and construction method for repairing and restoring the surface of concrete structures using the same}

The present invention is a shrinkage reduction type that can provide excellent physical strength and durability by forming a dense hardened body by suppressing cracking due to shrinkage reduction so as to improve the repair effect of the deteriorated cross section of concrete structures such as bridges and piers. It relates to a polymer-modified mortar composition and a cross-section restoration and repair method of a concrete structure using the same.

Concrete structures can prevent corrosion of internally embedded reinforcing bars due to the alkalinity of the concrete itself. However, the concrete alkalinity is either gradually eluted by the external environment, such as into and out of the water, due to the repeated generation of CaCO ₃ according to the CO ₂ gas inlet, concrete volume change (firing shrinkage, autogenous shrinkage, drying shrinkage, etc.) Concomitantly, it increases the concrete micropores and causes neutralization of the exterior and interior of concrete. Neutralization of concrete causes corrosion of reinforcing bars, and can also cause partial cracks and peeling of structures due to increased internal pressure, as well as collapse of structures. On the other hand, salt damage occurs in concrete structures exposed to the shore because chlorine ions contained in seawater and sea wind penetrate into the concrete and destroy the passivation film on the reinforcing bars.

In the event of damage such as cracks, peelings, or salt damage to concrete structures, especially bridge slabs, piers, central dividing walls of highways, road passage culverts, lower parts of bridges, underpasses, water purification plants, and sewage treatment plant structures, remove the concrete from the damaged area. Concrete section repair work is performed to restore the removed concrete section, and section repair mortar is used for concrete section section repair work. In this case, the cross-section repair mortar requires high chemical durability, smooth workability, high adhesion and compressive strength, and low shrinkage expansion rate.

In addition, mortar for cross-section restoration and repair of concrete structures generally uses more binder than concrete, so drying shrinkage is severe and cracks are frequent. When cracks occur in the mortar for cross-section restoration and repair, the durability of the mortar is reduced as well as the durability of the concrete to be restored. Moisture penetrates through cracks, and moisture acts as a means of transport for various harmful components and causes freeze-thaw, resulting in reduced durability.

Although the development of various materials and methods for repairing the deteriorated concrete section is in progress, the strength and durability performance are still insufficient. Therefore, there is an urgent need to develop a shrinkage-reducing polymer-modified mortar composition and a cross-section restoration and repair method of a concrete structure using the same so that a dense hardening body can be formed by suppressing cracking due to shrinkage reduction.

Republic of Korea Patent Registration No. 10-1760230 Republic of Korea Patent Registration No. 10-1815928 Republic of Korea Patent Registration No. 10-1914735

The present invention has been devised to solve the above-described problems, and an embodiment of the present invention suppresses cracking due to shrinkage reduction to form a dense hardened body, thereby providing excellent physical strength and durability, thereby providing concrete such as bridges, piers, etc. An object of the present invention is to provide a shrinkage-reducing polymer-modified mortar composition capable of effectively repairing the deteriorated cross-section of a structure, and a cross-section restoration and repair method of a concrete structure using the same.

Various problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

One embodiment of the present invention comprises 5 to 90% by weight of fine aggregate, 5 to 90% by weight of a shrinkage-reducing binder, 0.5 to 25% by weight of a polymer modifier, and 1 to 35% by weight of water;

The shrinkage-reducing binder is usually 100 parts by weight of Portland cement, 10 to 30 parts by weight of fine powder of blast furnace slag, 10 to 30 parts by weight of magnesium sulfoaluminate, 1 to 10 parts by weight of zirconium phosphate, 1 to 10 parts by weight of silica fume, and 1 to 10 parts by weight of strontium calcium oxide. 1 to 10 parts by weight, 1 to 10 parts by weight of fine eggshell membrane powder, and 1 to 10 parts by weight of halloysite;

The polymer modifier includes 100 parts by weight of a styrene-butadiene-styrene copolymer, 50 to 80 parts by weight of an acrylonitrile-butadiene-styrene copolymer, 50 to 80 parts by weight of a vinyl acetate-diethyl maleate copolymer, silicone-(meth)acrylic acid 10 to 30 parts by weight of the copolymer, 1 to 10 parts by weight of an aziridine-based silane compound represented by the following formula (1), 1 to 10 parts by weight of sodium glycerophosphate, and 1 to 10 parts by weight of tropolone. A mortar composition is provided.

[Formula 1]

In the above formula, Ph is a phenyl group.

The zirconium phosphate is zirconium phosphate whose surface is coated with polydopamine;

Zirconium phosphate whose surface is coated with polydopamine is pulverized to a particle size of 100 to 500 nm by pulverizing _{zirconium phosphate (Zr(HPO 4} ) ₂ ㆍH _{2 O) in deionized water to a particle size of 100 to 500 nm in a reactor} and dispersing while stirring at 20 to 60 °C for 0.2 to 1 hour; preparing zirconium phosphate whose surface is coated with polydopamine by dropwise adding deionized water in which the zirconium phosphate is dispersed to a dopamine solution; and filtering the zirconium phosphate coated with the polydopamine, washing and hot air drying.

The egg shell membrane fine powder is obtained by drying an egg shell, and then obtaining an egg shell membrane from the dried egg shell; acid-treating the obtained eggshell membrane by immersing it in an aqueous solution of 1.5 to 5 times the weight of 1 to 15% by weight of organic acid for 2 to 8 hours; After mixing 0.1 to 10 parts by weight of sodium benzoate with 100 parts by weight of the eggshell membrane immersion solution in which the acid treatment is completed, preparing a mixed dough having a moisture content of 20 to 35%; Putting the mixed dough into an ultraviolet irradiation device and irradiating ultraviolet rays; and drying the mixed dough exposed to ultraviolet light in the inside of the ultraviolet irradiation device to a moisture content of 15% or less, and then pulverizing to an average particle size of 200 to 600 μm.

In the step of making the mixture, 0.1 to 10 parts by weight of sodium benzoate, 0.05 to 5 parts by weight of a silane coupling agent represented by the following Chemical Formula 2, and 0.05 to 5 parts by weight of hinokitiol are added to 100 parts by weight of the acid-treated eggshell membrane immersion solution. After mixing, it may be a step of making a mixed dough having a moisture content of 20 to 35%.

[Formula 2]

In the above formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and n is 2 or 3.

In addition, another embodiment of the present invention is a cross-section restoration and repair method of a concrete structure using the shrinkage-reducing polymer-modified mortar composition,

Chipping and removing laitance, impurities, or deteriorated parts of the concrete structure with a grinder, a planer, a shot blaster, or a hand water jet, and arranging the base surface using a suction device; In order to improve adhesion between the cleaned substrate and the excellent shrinkage-reducing polymer-modified mortar composition, a primer or blooming treatment on the cleaned substrate; finishing the surface by pouring the shrinkage-reducing polymer-modified mortar composition on the primer or blooming-treated surface; finishing the surface by applying a surface protection and reinforcing coating agent to the finished surface; And it provides a cross-section restoration and repair method of a concrete structure comprising the step of curing.

According to the shrinkage-reducing polymer-modified mortar composition according to an embodiment of the present invention and the cross-section restoration and repair method of a concrete structure using the same, by suppressing cracking due to shrinkage reduction to form a dense hardened body, flexural strength, compressive strength, and adhesion strength It has excellent physical strength, such as long-term strength, as well as excellent initial strength and excellent adhesion performance, thereby securing workability. In addition, it can prevent corrosion and deterioration of concrete structures by providing very good durability such as salt decomposition resistance, neutralization resistance, water resistance, acid resistance, alkali resistance, abrasion resistance, freeze-thaw resistance, deodorization resistance, antibacterial property, contamination resistance, and self-repairing property. As a result, there is an effect that can increase the service period of concrete structures, reduce maintenance costs, and improve constructability. Thereby, there is an effect that can improve the repair effect of the deteriorated cross section of concrete structures such as bridges and piers.

Hereinafter, embodiments of the present invention will be described in detail. However, this is provided as an example, and the present invention is not limited thereto, and the present invention is only defined by the scope of the claims to be described later.

As used herein, the term "concrete structure" includes all concrete structures such as bridges, bridge lower slabs, piers, central dividing walls of highways, road passage culverts, lower parts of bridges, underpasses, water purification plants, sewage treatment plant structures, etc. used in meaning

One embodiment of the present invention comprises 5 to 90% by weight of fine aggregate, 5 to 90% by weight of a shrinkage-reducing binder, 0.5 to 25% by weight of a polymer modifier, and 1 to 35% by weight of water;

The shrinkage-reducing binder is usually 100 parts by weight of Portland cement, 10 to 30 parts by weight of fine powder of blast furnace slag, 10 to 30 parts by weight of magnesium sulfoaluminate, 1 to 10 parts by weight of zirconium phosphate, 1 to 10 parts by weight of silica fume, and 1 to 10 parts by weight of strontium calcium oxide. 1 to 10 parts by weight, 1 to 10 parts by weight of fine eggshell membrane powder, and 1 to 10 parts by weight of halloysite;

The polymer modifier includes 100 parts by weight of a styrene-butadiene-styrene copolymer, 50 to 80 parts by weight of an acrylonitrile-butadiene-styrene copolymer, 50 to 80 parts by weight of a vinyl acetate-diethyl maleate copolymer, silicone-(meth)acrylic acid 10 to 30 parts by weight of the copolymer, 1 to 10 parts by weight of an aziridine-based silane compound represented by the following formula (1), 1 to 10 parts by weight of sodium glycerophosphate, and 1 to 10 parts by weight of tropolone. A mortar composition is provided.

[Formula 1]

In the above formula, Ph is a phenyl group.

According to the shrinkage-reducing polymer-modified mortar composition according to an embodiment of the present invention and the cross-section restoration and repair method of a concrete structure using the same, by forming a dense hardened body by suppressing cracking due to shrinkage reduction, flexural strength, compressive strength, adhesion It has excellent physical strength such as strength, and has the effect of securing workability by expressing excellent initial strength and excellent adhesion performance as well as long-term strength. In addition, it can prevent corrosion and deterioration of concrete structures by providing very good durability such as salt decomposition resistance, neutralization resistance, water resistance, acid resistance, alkali resistance, abrasion resistance, freeze-thaw resistance, deodorization resistance, antibacterial property, contamination resistance, and self-repairing property. As a result, there is an effect that can increase the service period of concrete structures, reduce maintenance costs, and improve constructability. Thereby, there is an effect that can improve the repair effect of the deteriorated cross section of concrete structures such as bridges and piers.

The shrinkage-reducing polymer-modified mortar composition according to an embodiment of the present invention contains 5 to 90 wt% of fine aggregate, 5 to 90 wt% of a shrinkage-reducing binder, 0.5 to 25 wt% of a polymer modifier, and 1 to 35 wt% of water do.

In general, aggregate is divided into fine aggregate and coarse aggregate, coarse aggregate means aggregate having an average particle diameter of more than 5 mm, and fine aggregate used in the specification of the present invention means aggregate having an average particle diameter of 5 mm or less compared to coarse aggregate. used to mean The fine aggregate is preferably included in the range of 5 to 90 wt% with respect to the shrinkage reduction type polymer-modified mortar composition of the present invention.

More preferably, the fine aggregate includes 60 to 90% by weight of siliceous silica sand and 10 to 40% by weight of serpentine, so that excellent strength, fluidity, abrasion resistance, fire resistance, heat insulation, and durability such as acid resistance can be further improved. have.

More specifically, the siliceous silica sand having an average particle diameter of 0.01 to 2 mm may be preferably used. Thereby, it functions to greatly improve durability, such as excellent fluidity|liquidity, strength, and abrasion resistance. If the average particle diameter of the siliceous silica sand is too large, there is a fear that fluidity may be reduced, and if it is too small, workability may be reduced. In consideration of the above-described improvement effect, the siliceous silica sand is preferably contained in an amount of 60 to 90 wt % based on the fine aggregate.

In addition, the serpentine may preferably be used that has an average particle diameter of 0.01 to 2.9 mm. Thereby, it functions to greatly improve durability such as excellent strength, fluidity, lightness, fire resistance, heat insulation and acid resistance. The serpentine is preferably contained in an amount of 10 to 40% by weight based on the fine aggregate in consideration of the improvement effect described above.

On the other hand, the shrinkage-reducing binder has excellent flexural strength, compressive strength, adhesion strength, etc., provides excellent shrinkage reduction effect and crack resistance, and has durability such as abrasion resistance and deodorization, antibacterial performance, water resistance, acid and salt resistance. function to improve. In addition, by providing excellent hardening performance, high flowability and high viscosity in a wet environment, material separation is suppressed, material loss can be prevented, and excellent self-leveling properties can be provided. The shrinkage-reducing binder is preferably included in an amount of 5 to 90% by weight with respect to the shrinkage-reducing polymer-modified mortar composition of the present invention.

The shrinkage-reducing binder is usually 100 parts by weight of Portland cement, 10 to 30 parts by weight of fine powder of blast furnace slag, 10 to 30 parts by weight of magnesium sulfoaluminate, 1 to 10 parts by weight of zirconium phosphate, 1 to 10 parts by weight of silica fume, and 1 to 10 parts by weight of strontium calcium oxide. 1 to 10 parts by weight, 1 to 10 parts by weight of fine eggshell membrane powder, and 1 to 10 parts by weight of halloysite may be preferably used.

More specifically, the normal Portland cement may be preferably used as specified in KS.

Hereinafter, the content of other components constituting the shrinkage-reducing binder is based on 100 parts by weight of the normal Portland cement.

The fine powder of blast furnace slag is used to enhance latent hydraulic properties, long-term strength expression and durability.

This fine powder of blast furnace slag is a by-product of the steel industry _{, and its main components are CaO and SiO 2} , and although its composition is similar to that of cement, it _{does not generate CO 2} , so it is environmentally friendly. More specifically, the fine blast furnace slag powder is generated during the blast furnace iron making process, and by spraying and quenching the high-temperature molten blast furnace slag at the time of slag discharge, water-based slag formed into amorphous granules with an average particle diameter of less than 5 mm can be used. In addition, by pulverizing the water-based slag, a powder having a fineness of 4,000 to 7,500 cm 2 /g may be preferably used.

The fine blast furnace slag powder is preferably contained in an amount of 10 to 30 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of the fine blast furnace slag powder is too small, the improvement effect may be insufficient, and when the content of the fine blast furnace slag powder is too large, there is a problem that the initial strength may be lowered.

The magnesium sulfoaluminate greatly improves the initial strength expression and shrinkage prevention effect, so that it can be cured within a short time and can further improve the ease of construction with a short construction time, and the function of preventing material loss by inhibiting material separation do.

The magnesium sulfoaluminate is preferably contained in an amount of 10 to 30 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of the magnesium sulfoaluminate is too small, there is a problem that the above-described improvement effect may be insufficient. There is a problem in that price competitiveness may be lowered.

The zirconium phosphate functions to improve excellent strength expression, anti-shrinkage effect, and improve abrasion resistance, fire resistance and corrosion resistance. In addition, by improving the fluidity, it functions to improve the workability.

The zirconium phosphate uses a zirconium phosphate whose surface is coated with polydopamine, and not only improves the above-mentioned improvement effect, but also provides excellent bonding strength, so that the coating layer is further applied before the hydration bonding of the water-soluble binder in the construction surface proceeds. By stabilizing it, there is an effect that can prevent sagging and maintain a lining of a certain thickness. Accordingly, after construction, there is an effect that can implement resistance to shrinkage and cracking and excellent durability.

More specifically, zirconium phosphate whose surface is coated with polydopamine is pulverized to a particle size of 100 to 500 nm through a basket mill by _{zirconium phosphate (Zr(HPO 4} ) ₂ ㆍH _{2 O) in deionized water.} After being put into a reactor, dispersing while stirring at 20 to 60 ℃ for 0.2 to 1 hour; preparing zirconium phosphate whose surface is coated with polydopamine by dropwise adding deionized water in which the zirconium phosphate is dispersed to a dopamine solution; and filtering the zirconium phosphate coated with polydopamine, washing and hot air drying.

In this case, the dopamine solution is prepared by dissolving at least one selected from the group consisting of dopamine hydrochloride, norepinephrine hydrochloride, epinephrine hydrochloride, and mixtures thereof in a solvent. can In addition, the solvent may be at least one selected from the group consisting of a buffer solution, ethylene glycol, dimethyl sulfoxide, dimethyl formamide, and mixtures thereof. .

In addition, in the step of filtering the polydopamine-coated zirconium phosphate, washing and hot air drying, the polydopamine-coated zirconium phosphate is filtered, washed with deionized water and far-infrared rays at 75 to 115° C. for 4 to 12 hours. It can be carried out by hot air drying with a dryer.

The zirconium phosphate is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of zirconium phosphate is too small, there is a problem that the above improvement effect may be insufficient. There are possible problems.

The silica fume is microsilica particles that are collected by collecting and filtering the gas generated in the production process of silicon iron and silicon metal. Since the fineness is very high and the amount of silica is large, it can be filled between cement particles, so that a very dense hardened structure is obtained. It can function to express excellent strength.

The silica fume is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of the silica fume is too small, there is a problem that the improvement effect may be insufficient, and when the content of the silica fume is too large, there is a problem that the curing speed is delayed or a material separation phenomenon may occur.

The strontium calcium oxide has a function of improving excellent strength expression, anti-shrinkage effect, and improving abrasion resistance, watertightness and corrosion resistance. In addition, by performing a role as an alkali stimulant of the fine powder of the blast furnace slag, it functions to improve the initial strength.

More specifically, the strontium calcium oxide is prepared by mixing and stirring the strontium (Sr) nitrate compound and the calcium (Ca) nitrate compound so that the molar ratio of Sr to Ca is 1: 0.8 to 1.2 to prepare a mixed solution, and then the mixed solution After impregnating in starch, heat treatment at 800 to 1,200 ° C. is used to very effectively prevent surface cracking and expansion fracture caused by drying and shrinkage, so that excellent crack resistance can be more effectively improved.

The strontium calcium oxide is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of strontium calcium oxide is too small, there is a problem that the above-described improvement effect may be insufficient. When the content of strontium calcium oxide is too large, it is difficult to expect any further improvement effect, and the manufacturing cost is high, so that the price competitiveness is high. There is a problem that can be degraded.

The egg shell membrane fine powder has excellent self-healing properties, thereby reducing shrinkage and effectively improving crack resistance. In addition, by exhibiting high flow in a wet environment, material separation and material loss can be prevented, and settling or shrinkage in an uncured state is prevented, so that continuous pouring and water quality can be achieved even in deep water and in places with a lot of leachate. It functions to greatly improve constructability and eco-friendliness such as pollution prevention.

Such fine egg shell membrane powder has the effect of further improving the above-mentioned effect by using the one irradiated with ultraviolet rays.

More specifically, the fine eggshell membrane powder may be obtained by drying an eggshell, and then obtaining an eggshell membrane from the dried eggshell; acid-treating the obtained eggshell membrane by immersing it in an aqueous solution of 1.5 to 5 times the weight of 1 to 15% by weight of organic acid for 2 to 8 hours; After mixing 0.1 to 10 parts by weight of sodium benzoate with 100 parts by weight of the eggshell membrane immersion solution in which the acid treatment is completed, preparing a mixed dough having a moisture content of 20 to 35%; Putting the mixed dough into an ultraviolet irradiation device and irradiating ultraviolet rays; And after drying the mixed dough exposed to UV light in the inside of the UV irradiation device to a moisture content of 15% or less, it can be preferably used that is prepared by a manufacturing method comprising the step of pulverizing to an average particle size of 200 to 600 μm.

At this time, the drying of the eggshell may be performed at 70 to 100 ℃ for 1 to 4 hours.

In addition, the organic acid may be at least one selected from the group consisting of formic acid, acetic acid, butyric acid, palmitic acid, oxalic acid, benzoic acid, salicylic acid, citric acid, stearic acid, uric acid, and mixtures thereof. A more preferable organic acid may be a mixture of citric acid and stearic acid in a weight ratio of 1: 0.1 to 0.5.

In addition, the step of irradiating the ultraviolet rays may be performed by irradiating the ultraviolet rays for 3 to 24 hours so that 20 to 100 W of energy per unit area is supplied in the ultraviolet irradiation device.

In addition, in the step of making the mixed dough, 0.1 to 10 parts by weight of sodium benzoate, 0.05 to 5 parts by weight of a silane coupling agent represented by the following Chemical Formula 2, and 0.05 to 5 parts by weight of hinokitiol in 100 parts by weight of the acid-treated eggshell membrane immersion solution After further mixing the parts, it may be a step of making a mixed dough having a moisture content of 20 to 35%. Thereby, it is possible not only to further improve the above-mentioned effects, but also to provide more excellent shrinkage reduction effect and crack resistance, and provide faster curing properties, thereby suppressing material separation and preventing material loss more effectively. .

[Formula 2]

In the above formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and n is 2 or 3.

The fine eggshell membrane powder is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of the fine eggshell membrane powder is too small, there is a problem that the above improvement effect may be insufficient. There are problems that could be.

The halloysite provides excellent crack resistance due to low expansion rate due to water absorption, and furthermore, even when cracks occur due to external impact, etc., the gelation reaction is continuously induced by the moisture absorbed in the pores to promote long-term stability of strength by itself. It functions to provide the self-healing ability that makes it possible.

The halloysite is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the normal Portland cement. When the content of halloysite is too small, the above improvement effect may be insufficient, and when the content of halloysite is too large, the curing speed is delayed or the manufacturing cost is increased, so that price competitiveness may be lowered. There is this.

On the other hand, the polymer modifier further improves adhesion, fluidity, cohesion and material separation prevention, and has very good strength, shrinkage reduction effect, crack resistance, salt decomposition resistance, neutralization resistance, water resistance, acid resistance, alkali resistance, abrasion resistance, freeze-thaw resistance It functions to further improve durability such as deodorization, antibacterial, stain resistance, and self-retaining properties. The polymer modifier is preferably included in an amount of 0.5 to 25 wt% with respect to the shrinkage reduction type polymer-modified mortar composition of the present invention.

The polymer modifier includes 100 parts by weight of a styrene-butadiene-styrene copolymer, 50 to 80 parts by weight of an acrylonitrile-butadiene-styrene copolymer, 50 to 80 parts by weight of a vinyl acetate-diethyl maleate copolymer, silicone-(meth)acrylic acid 10 to 30 parts by weight of the copolymer, 1 to 10 parts by weight of the aziridine-based silane compound represented by the following Chemical Formula 1, 1 to 10 parts by weight of sodium glycerophosphate, and 1 to 10 parts by weight of tropolone may be preferably used.

[Formula 1]

In the above formula, Ph is a phenyl group.

The styrene-butadiene-styrene copolymer functions to improve very excellent adhesion and strength, shrinkage reduction effect, crack resistance, cohesive force, material separation prevention property and durability.

Hereinafter, the content of other components constituting the polymer modifier is based on 100 parts by weight of the styrene-butadiene-styrene copolymer.

The acrylonitrile-butadiene-styrene copolymer functions to improve durability such as excellent adhesion, strength, fluidity, material separation resistance, freeze-thaw resistance, chemical resistance, water permeability resistance, waterproofness, and water resistance.

The acrylonitrile-butadiene-styrene copolymer is preferably contained in an amount of 50 to 80 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of the acrylonitrile-butadiene-styrene copolymer is too small, there is a problem that the above-described improvement effect may be insufficient. There is a problem in that price competitiveness may be lowered due to delay or increased manufacturing cost.

The vinyl acetate-diethyl maleate copolymer functions to improve durability such as flexural strength, adhesion strength, shrinkage reduction effect, crack resistance, salt decomposition resistance, neutralization resistance, and freeze-thaw resistance.

The vinyl acetate-diethyl maleate copolymer is preferably contained in an amount of 50 to 80 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of the vinyl acetate-diethyl maleate copolymer is too small, there is a problem that the above-described improvement effect may be insufficient, and when the content of the vinyl acetate-diethyl maleate copolymer is too large, the viscosity increases too much There is a problem that workability may be deteriorated.

The silicone-(meth)acrylic acid copolymer functions to improve durability such as excellent adhesion, strength, fluidity, material separation resistance, waterproofness, water resistance, self-retaining property and heat resistance.

The silicone-(meth)acrylic acid copolymer is preferably contained in an amount of 10 to 30 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of the silicone-(meth)acrylic acid copolymer is too small, there is a problem that the above-described improvement effect may be insufficient, and when the content of the silicone-(meth)acrylic acid copolymer is too large, the manufacturing cost increases and price competitiveness There is a problem that this can be degraded.

The aziridine-based silane compound represented by Formula 1 improves adhesion strength, and functions to improve durability such as very excellent strength, crack resistance, and stain resistance.

The aziridine-based silane compound represented by Formula 1 is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of the aziridine-based silane compound represented by the formula (1) is too small, there is a problem that the above-described improvement effect may be insufficient. There is a problem in that price competitiveness may be lowered.

The sodium glycerophosphate has excellent strength, adhesion, anti-shrinking effect, fluidity, cohesive force and material separation prevention, salt decomposition resistance, neutralization resistance, acid resistance, alkali resistance, freeze-thaw resistance, self-retaining properties, etc. It functions to improve durability .

The sodium glycerophosphate is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of the sodium glycerophosphate is too small, there is a problem that the above-described improvement effect may be insufficient, and when the content of the sodium glycerophosphate is too large, the manufacturing cost increases and the price competitiveness may decrease. .

The tropolone functions to improve durability such as excellent fluidity, antibacterial properties, antioxidant effects, acid resistance, salt decomposition resistance and freeze-thaw resistance.

The tropolone is preferably contained in an amount of 1 to 10 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer. When the content of tropolone is too small, there is a problem that the above-described improvement effect may be insufficient.

The polymer modifier may further include additives commonly used in the art. For example, an antifoaming agent, a water reducing agent, and the like can be used.

More specifically, the polymer modifier may further include an antifoaming agent to increase strength and durability by removing air bubbles in the composition. In addition, when the antifoaming agent is added to the polymer modifier, it is possible to improve workability and pot life by imparting an air entrainment effect. The antifoaming agent is preferably contained in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer.

Non-limiting examples of the anti-foaming agent include alcohol-based anti-foaming agents, silicone-based anti-foaming agents, fatty acid-based anti-foaming agents, oil-based anti-foaming agents, ester-based anti-foaming agents, oxyalkylene-based anti-foaming agents, and the like. Examples of the silicone-based antifoaming agent include dimethyl silicone oil, polyorganovinylidene chloride-vinyl chloride, and fluorosilicone oil. Examples of the fatty acid-based antifoaming agent include stearic acid and oleic acid. The oil-based antifoaming agent includes kerosene, animal and vegetable oil, castor oil, and the like. Examples of the ester-based antifoaming agent include solitol trioleate and glycerol monoricinolate. Examples of the oxyalkylene-based antifoaming agent include polyoxyalkylene, acetylene ethers, polyoxyalkylene fatty acid esters, and polyoxyalkylenealkylamines. The alcohol-based antifoaming agent includes glycol (glycol) and the like.

In addition, the polymer modifier may further include a water-reducing agent to further improve strength and durability by reducing the water-cement ratio, and to secure fluidity. The water reducing agent is preferably contained in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the styrene-butadiene-styrene copolymer.

As a non-limiting example of the water reducing agent, a polycarboxylic acid-based, melamine-based or naphthalene-based water reducing agent may be used. However, it is preferable to use a polycarboxylic acid water reducing agent that does not reduce the strength, workability and pot life of the composition because naphthalene-based and melamine-based compositions have lower strength compared to polycarboxylic acids and may reduce workability and pot life. do.

Hereinafter, a method for producing a shrinkage-reducing polymer-modified mortar composition according to an embodiment of the present invention will be described.

The shrinkage-reducing polymer-modified mortar composition is prepared by premixing 5 to 90 wt% of a fine aggregate and 5 to 90 wt% of a shrinkage-reducing binder in a vacuum type forced mixer, and then 0.5 to 25 wt% of a polymer modifier and 1 to 35 wt% of water By further adding weight%, it can be prepared by mixing with a forced mixer or a continuous mixer for a predetermined time (eg, 1 to 10 minutes).

In addition, another embodiment of the present invention is a cross-section restoration and repair method of a concrete structure using the shrinkage-reducing polymer-modified mortar composition,

Chipping and removing laitance, impurities, or deteriorated parts of the concrete structure with a grinder, a planer, a shot blaster, or a hand water jet, and arranging the base surface using a suction device; In order to improve adhesion between the cleaned substrate and the excellent shrinkage-reducing polymer-modified mortar composition, a primer or blooming treatment on the cleaned substrate; finishing the surface by pouring the shrinkage-reducing polymer-modified mortar composition on the primer or blooming-treated surface; finishing the surface by applying a surface protection and reinforcing coating agent to the finished surface; And it provides a cross-section restoration and repair method of a concrete structure comprising the step of curing.

In this case, the method may further include removing the deteriorated portion to a lower portion of the reinforcing bar, and removing rust of the exposed reinforcing bar before the primer or blooming treatment step.

When the laitance, impurities, or deteriorated parts of the concrete structure are removed by chipping with a grinder, planer, shot blaster, or hand water jet, the reinforcing bars of the concrete structure are not exposed in normal cases, but in the case of severe deterioration, the The reinforcing bar may be exposed, and when the reinforcing bar is exposed in this way, it may further include a step of anti-rust treatment.

In addition, the primer or blooming treatment is selected from the group consisting of styrene-butadiene latex (copolymer), polyacrylic ester, acryl, ethyl vinyl acetate, methyl methacrylate, silane-based compounds, and mixtures thereof. A material including one or more may be used, but is not limited thereto.

In addition, the surface protection and reinforcing coating agent is one selected from the group consisting of styrene-butadiene latex, poly acrylic ester, acrylic, ethyl vinyl acetate, methyl methacrylate, silica-silane-based compound (condensation polymerization mixture), and mixtures thereof. Materials including the above may be used, but the present invention is not limited thereto.

According to the shrinkage-reducing polymer-modified mortar composition according to an embodiment of the present invention and the cross-section restoration and repair method of a concrete structure using the same, by suppressing cracking due to shrinkage reduction to form a dense hardened body, flexural strength, compressive strength, and adhesion strength It has excellent physical strength, such as long-term strength, as well as excellent initial strength and excellent adhesion performance, thereby securing workability. In addition, it can prevent corrosion and deterioration of concrete structures by providing very good durability such as salt decomposition resistance, neutralization resistance, water resistance, acid resistance, alkali resistance, abrasion resistance, freeze-thaw resistance, deodorization resistance, antibacterial property, contamination resistance, and self-repairing property. As a result, there is an effect that can increase the service period of concrete structures, reduce maintenance costs, and improve constructability. Thereby, there is an effect that can improve the repair effect of the deteriorated cross section of concrete structures such as bridges and piers.

As mentioned above, although preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various modifications can be made by those skilled in the art within the scope of the technical spirit of the present invention. This is possible.

<Production Example 1>

Preparation of zirconium phosphate whose surface is coated with polydopamine

Zirconium phosphate (Zr(HPO ₄ ) ₂ ㆍH ₂ O) in deionized water was pulverized to a particle size of about 197 nm through a basket mill, put into a reactor, and dispersed while stirring at 55° C. for 30 minutes. . The deionized water in which the zirconium phosphate was dispersed was added dropwise to the dopamine solution to prepare a zirconium phosphate surface coated with polydopamine. At this time, as the dopamine solution, 200 mg of dopamine hydrochloride was dissolved in 100 mL of a solvent prepared by dissolving Tris-buffer, trizma base) in water to a concentration of 10 mM. Thereafter, the polydopamine-coated zirconium phosphate was filtered, washed with deionized water and hot air dried at 105° C. for 7 hours with a far-infrared dryer, thereby preparing zirconium phosphate coated with polydopamine.

<Preparation Example 2>

Preparation of strontium calcium oxide

A solution having a solid content of 60 wt% and a solution having a solid content of 60 wt% using Sr(NO ₃ ) _{2 and a solution having a solid content of 30 wt% using Ca(NO 3} ) ₂ ㆍ4H ₂ O were prepared, respectively, and then the two solutions were mixed And stirred to prepare a mixed solution. The mixed solution was impregnated with starch and then heat-treated in an electric furnace at a temperature of 1,100° C. to prepare strontium calcium oxide (SrCaO) powder.

<Production Example 3>

Preparation of eggshell membrane powder

After drying the eggshell at 100° C. for 2 hours, an eggshell membrane was obtained from the dried eggshell. The obtained egg shell membrane was acid-treated by immersing it in an aqueous solution of 3 times the weight of 10 wt% citric acid for 6 hours. The acid-treated eggshell membrane immersion solution was filtered and washed, and then dried with hot air at 50°C. By pulverizing the dried eggshell membrane to an average particle diameter of 400 μm, a fine eggshell membrane powder was prepared.

<Production Example 4>

Preparation of fine powder of eggshell membrane irradiated with ultraviolet light

After drying the eggshell at 100° C. for 2 hours, an eggshell membrane was obtained from the dried eggshell. The obtained eggshell membrane was acid-treated by immersing it in 3 times the weight of a 9% by weight aqueous solution of organic acid (citric acid and stearic acid mixed in a 1:0.5 weight ratio) for 6 hours. After filtration and washing of the acid-treated eggshell membrane immersion solution, 8 parts by weight of sodium benzoate was mixed with 100 parts by weight of the acid-treated eggshell membrane immersion solution, and then a mixed dough having a moisture content of 25% was prepared. The prepared mixture was put into an ultraviolet irradiation device and irradiated with ultraviolet rays for 19 hours so that 100 W of energy was supplied. Thereafter, the mixed dough exposed to UV light inside the UV irradiation device was dried with hot air at 50° C. so that the moisture content was 15% or less, and then pulverized to an average particle size of 400 μm to prepare a fine eggshell membrane powder.

<Preparation Example 5>

Preparation of fine powder of eggshell membrane irradiated with ultraviolet light

After drying the eggshell at 100° C. for 2 hours, an eggshell membrane was obtained from the dried eggshell. The obtained eggshell membrane was acid-treated by immersing it in 3 times the weight of a 9% by weight aqueous solution of organic acid (citric acid and stearic acid mixed in a 1:0.5 weight ratio) for 6 hours. After filtration and washing of the acid-treated egg shell membrane immersion solution, 100 parts by weight of the acid-treated egg shell membrane immersion solution, 8 parts by weight of sodium benzoate, 3 parts by weight of a silane coupling agent represented by the following Chemical Formula 2-1, and hinokitiol After mixing 2 parts by weight, a mixed dough having a moisture content of 25% was prepared. The prepared mixture was put into an ultraviolet irradiation device and irradiated with ultraviolet light for 19 hours so that 100 W of energy was supplied. Thereafter, the mixed dough exposed to UV light inside the UV irradiation device was dried with hot air at 50° C. so that the moisture content was 15% or less, and then pulverized to an average particle size of 400 μm, thereby preparing a fine eggshell membrane powder.

[Formula 2-1]

In the above formula, R is a methyl group, X is an ethyl group, and n is 2.

<Examples and Comparative Examples>

The fine aggregate and shrinkage-reducing binder mixed in the components and contents shown in Table 1 below were put into a vacuum type forced mixing mixer, and after premixing for 3 minutes under dry mixing conditions, the components as shown in Table 1 below And the polymer modifier and water mixed in the content were further added and mixed for 2 minutes to prepare a shrinkage-reducing polymer-modified mortar composition and a comparative concrete composition.

Hereinafter, the experimental results comparing the characteristics of the Examples according to the present invention with those of Comparative Examples 1 and 2 so as to more easily understand the characteristics of the shrinkage-reducing polymer-modified mortar composition prepared according to Examples 1 to 3 are presented. it has been shown

<Test Example 1>

The shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar composition prepared in Comparative Examples 1 and 2 were subjected to a flow test (flowability during non-strike) according to the method specified in KS L 5220. carried out. At this time, material separation was judged by stirring the mortar slurry by hand, and the underwater specimen was produced by installing a mold 10 cm below the water surface and then free-falling. The results are shown in Table 1.

As shown in Table 2 above, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention had better flowability at the time of non-strike compared to the comparative mortar compositions prepared in Comparative Examples 1 and 2 It was confirmed that very high, the shrinkage-reducing polymer-modified mortar composition of the present invention was found to have excellent fluidity. In addition, although material separation occurred in the comparative mortar compositions prepared in Comparative Examples 1 and 2, the shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 did not cause material separation, and thus excellent inseparability in water. And it was found.

<Test Example 2>

In order to compare the physical properties of the shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar compositions prepared in Comparative Examples 1 and 2, the shrinkage reduction prepared in Examples 1 to 3 described above The reduced-type polymer-modified mortar composition and the comparative mortar composition prepared in Comparative Examples 1 and 2 were tested for flexural strength, compressive strength and adhesive strength according to KS F 4042 (Test method for polymer cement mortar for repairing concrete structures), The results are shown in Table 3, respectively.

As shown in Table 3, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention were compared to the comparative mortar compositions prepared in Comparative Examples 1 and 2, in terms of flexural strength, compressive strength and adhesive strength. was found to be significantly superior.

<Test Example 3>

The shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar composition prepared in Comparative Examples 1 and 2 were subjected to length change rate, chloride ion penetration resistance and neutralization tests according to KS F 4042, and the The results are shown in Table 4, respectively.

As shown in Table 4, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention were compared with the comparative mortar compositions prepared in Comparative Examples 1 and 2, in terms of length change rate, chloride ion penetration resistance, and excellent neutralization resistance.

<Test Example 4>

The shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar composition prepared in Comparative Examples 1 and 2 were subjected to a freeze-thaw resistance test according to the method stipulated in KS F 2456, and the results were obtained. It is shown in Table 5 below. At this time, freeze-thaw refers to the freezing and melting of moisture absorbed in concrete, and if freeze-thawing is repeated, microcracks are generated in the concrete structure, resulting in a problem of reduced durability. The results in Table 5 below indicate the durability index of each Example and Comparative Examples 1 and 2 according to the freeze-thaw resistance test.

As shown in Table 5, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention have a significantly higher durability index than the comparative mortar compositions prepared in Comparative Examples 1 and 2, It can be seen that the freeze-thaw resistance and durability are improved.

<Test Example 5>

2% of the shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar composition prepared in Comparative Examples 1 and 2 according to the Japanese Industrial Standards [Method for testing chemical resistance by solution deposition of concrete] Chemical resistance was evaluated by immersing the specimens for 28 days in an aqueous solution of hydrochloric acid, 5% sulfuric acid and 45% sodium hydroxide as a test solution, and the results are shown in Table 6 below, respectively.

As shown in Table 6, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention had a weight change rate for chemical resistance compared to the comparative mortar compositions prepared in Comparative Examples 1 and 2 It appeared less, which means that the chemical resistance is excellent.

<Test Example 6>

Alkali resistance, water permeability, water absorption coefficient and moisture permeation resistance tests according to KS F 4042 were performed on the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 and the comparative mortar compositions prepared in Comparative Examples 1 and 2 did; A deodorization test was performed by measuring the deodorization rate of ammonia gas by KFIA-FI-1004; Antibacterial test according to KS A 0702 was performed, and the results are shown in Table 7 below, respectively.

As shown in Table 7, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention have excellent alkali resistance and water permeability compared to the comparative mortar compositions prepared in Comparative Examples 1 and 2 It can be seen that this is low, the water absorption coefficient is low, and the moisture permeation resistance, deodorization and antibacterial properties are excellent.

<Test Example 7>

In order to evaluate the self-healing properties of the shrinkage-reducing polymer-modified mortar composition prepared in Examples 1 to 3 and the comparative mortar compositions prepared in Comparative Examples 1 and 2, each of the mortar specimens was prepared in a size of 50 × 50 × 50 mm, After curing, the compressive strength recovery rate was measured after 28, 56 and 84 days of dry curing after preloading with a compressive load of 85% of the maximum compressive load, and the results are shown in Table 8 below.

As shown in Table 8, the shrinkage-reducing polymer-modified mortar compositions prepared in Examples 1 to 3 of the present invention had a higher recovery rate of compressive strength after cracking compared to the comparative mortar compositions prepared in Comparative Examples 1 and 2 It was confirmed that the self-healing properties were excellent.

As described above, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without changing the technical spirit or essential characteristics thereof. Therefore, it should be understood that all of the embodiments described above are illustrative and not restrictive. The scope of the present invention should be construed as being included in the scope of the present invention, rather than the above detailed description, all changes or modifications derived from the meaning and scope of the claims to be described later and their equivalents.

Claims (5)

5 to 90% by weight of fine aggregate, 5 to 90% by weight of a shrinkage-reducing binder, 0.5 to 25% by weight of a polymer modifier, and 1 to 35% by weight of water;
The shrinkage-reducing binder is usually 100 parts by weight of Portland cement, 10 to 30 parts by weight of fine powder of blast furnace slag, 10 to 30 parts by weight of magnesium sulfoaluminate, 1 to 10 parts by weight of zirconium phosphate, 1 to 10 parts by weight of silica fume, and 1 to 10 parts by weight of strontium calcium oxide. 1 to 10 parts by weight, 1 to 10 parts by weight of fine eggshell membrane powder, and 1 to 10 parts by weight of halloysite;
The polymer modifier is styrene-butadiene-styrene copolymer 100 parts by weight, acrylonitrile-butadiene-styrene copolymer 50 to 80 parts by weight, vinyl acetate-diethyl maleate copolymer 50 to 80 parts by weight, silicone- (meth) acrylic acid 10 to 30 parts by weight of the copolymer, 1 to 10 parts by weight of an aziridine-based silane compound represented by the following formula (1), 1 to 10 parts by weight of sodium glycerophosphate, and 1 to 10 parts by weight of tropolone. Polymer modified mortar composition.
[Formula 1]

In the above formula, Ph is a phenyl group. According to claim 1,
The zirconium phosphate is zirconium phosphate whose surface is coated with polydopamine;
Zirconium phosphate whose surface is coated with polydopamine is pulverized to a particle size of 100 to 500 nm by pulverizing _{zirconium phosphate (Zr(HPO 4} ) ₂ ㆍH _{2 O) in deionized water to a particle size of 100 to 500 nm in a reactor} and dispersing while stirring at 20 to 60 °C for 0.2 to 1 hour; preparing zirconium phosphate whose surface is coated with polydopamine by dropwise adding deionized water in which the zirconium phosphate is dispersed to a dopamine solution; and filtering the zirconium phosphate coated with polydopamine, washing and hot air drying. According to claim 1,
The eggshell membrane powder is
After drying the eggshell, obtaining an eggshell membrane from the dried eggshell; acid-treating the obtained eggshell membrane by immersing it in an aqueous solution of 1.5 to 5 times the weight of 1 to 15% by weight of organic acid for 2 to 8 hours; After mixing 0.1 to 10 parts by weight of sodium benzoate with 100 parts by weight of the eggshell membrane immersion solution in which the acid treatment is completed, preparing a mixed dough having a moisture content of 20 to 35%; Putting the mixed dough into an ultraviolet irradiation device and irradiating ultraviolet rays; And after drying the mixed dough exposed to UV light in the inside of the UV irradiation device to a moisture content of 15% or less, and then pulverizing to an average particle size of 200 to 600 μm. Polymer modified mortar composition. 4. The method of claim 3,
The step of making the mixed dough is
0.1 to 10 parts by weight of sodium benzoate, 0.05 to 5 parts by weight of a silane coupling agent represented by the following Chemical Formula 2, and 0.05 to 5 parts by weight of hinokitiol are further mixed with 100 parts by weight of the acid-treated eggshell membrane immersion solution, followed by a moisture content of 20 Shrink-reducing polymer-modified mortar composition, characterized in that the step of making a mixed dough of to 35%.
[Formula 2]

In the above formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and n is 2 or 3. As a cross-section restoration and repair method of a concrete structure using the shrinkage-reducing polymer-modified mortar composition according to any one of claims 1 to 4,
Chipping and removing laitance, impurities, or deteriorated parts of the concrete structure with a grinder, a planer, a shot blaster, or a hand water jet, and arranging the base surface using a suction device; In order to improve the adhesion between the cleaned substrate and the excellent shrinkage-reducing polymer-modified mortar composition, a primer or blooming treatment on the cleaned substrate; finishing the surface by pouring the shrinkage-reducing polymer-modified mortar composition on the primer or blooming-treated surface; finishing the surface by applying a surface protection and reinforcing coating agent to the finished surface; And cross-section restoration and repair method of a concrete structure comprising the step of curing.