KR101861064B1 - Mortar composition for cross section ristirations and method for recovering the same thereof - Google Patents

Abstract

The present invention relates to a mortar composition for preventing salt damage and freezing and thawing and a repair method for a road gutter by salt damage and an end surface of a concrete structure suffering from neutralization and chemical damage using the same. An objective of the present invention is to provide a mortar composition for preventing salt damage and freezing and thawing and a repair method for a road gutter by salt damage and an end surface of a concrete structure suffering from neutralization and chemical damage using the same which can remove a degraded portion of concrete damaged by salt and freezing and thawing. The mortar composition for preventing salt damage and freezing and thawing and the repair method for a road gutter by salt damage and an end surface of a concrete structure suffering from neutralization and chemical damage using the same to remove a degradation portion of a concrete structure caused by salt damage and freezing and thawing, install attaching reinforcement hardware, and then apply a mortar composition for preventing salt damage and freezing and thawing. The mortar composition comprises 20-45 wt% of a cement component, 3-15 wt% of a rapid hardener, 5-20 wt% of an admixture, 25-55 wt% of silica filler, 1-5 wt% of latex, 0.01-0.3 wt% of a carbon nanotube mixed solution, 0.5-4 wt% of a polymer resin, 0.2-2 wt% of a superplasticizer, 0.01-0.8 wt% of amorphous steel fiber, 0.1-3 wt% of a water repellent, 0.2-2 wt% of a property enhancer, and 0.005-1 wt% of graphene oxide.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mortar composition for preventing corrosion and freezing and thawing of a concrete structure and a method for recovering the same from a road surface,

The present invention relates to a mortar composition for preventing corrosion and freezing and thawing, and a method for repairing a concrete structure subjected to damage caused by road corrosion, neutralization, and chemical damage caused by salting thereof. A mortar composition for preventing corrosion and freezing and thawing which can be quickly repaired by a mortar composition for preventing the freezing and thawing with the adhesion strength and the compressive strength, and a concrete structure which is damaged by the road side, neutralization, Maintenance method.

The civil engineering and building facilities using concrete are playing a very important role in the national economy for the centennial era as a national infrastructure. These concrete structures have semi-permanent lifetime of more than 100 years, but they cause corrosion of the concrete caused by increasingly serious atmospheric environment pollution, especially chloride, neutralization and chemical corrosion, and as a result, corrosion of reinforcing steel, which is the main material of reinforced concrete, There is a phenomenon that the life is remarkably shortened.

3CaOSiO ₂ and 2CaOSiO _{2, which} are the main constituents of concrete, react with hydration with water to produce hydrated calcium silicate and a large amount of calcium hydroxide as shown in the following formula.

_{2 (2CaOSiO 2) + 3H 2} O → 3CaO2SiO 2 3H 2 O + Ca (OH) 2

Therefore, continuous capillary pores in concrete are filled with an alkaline solution of pH 12-13, which is a saturated aqueous solution of calcium hydroxide. In such an alkaline environment, the surface of the reinforcing bar is covered with a protective coating called a thin passive coating (thickness of 20 to 60 Å, γ-Fe ₂ O ₃ nH ₂ O), so that the reinforcing bars embedded in the concrete generally have corrosion It does not.

However, if the action of carbon dioxide in the air is received for a long period of time, the calcium hydroxide in the concrete gradually turns into calcium carbonate, and the pH is lowered to about 0.8 to 10, so that the concrete is lost in alkalinity. The corrosion of the reinforcing bars in the concrete is rapidly generated due to the deterioration of the alkalinity. In addition, when chlorides enter the concrete, chloride ion breaks the passive film and corrosion of the reinforcing bar occurs.

As described above, when the reinforcing bars in the concrete are corroded, rust, which is a corrosion product, is generated to reach 2 to 3 times the original volume, and cracks are generated in the covered concrete due to such expansion pressure. Therefore, the surface concrete is peeled off, The strength and durability of the entire concrete structure are lost.

In addition, although it is widely used as a general snow removal method to dissolve snow by applying calcium chloride on the road when a lot of snow is caught on the road in the winter, the calcium chloride is a concrete and an alkaline earth, and when the calcium chloride component penetrates into the concrete, the alkali of the concrete is lowered, And the function of the concrete structure is deteriorated.

 In winter, concrete may be damaged due to frozen and thawed concrete, and if it is exposed to automobile exhaust gas for a long time, the inner reinforcing steel may be corroded due to neutralization phenomenon, and concrete may crack or fall off .

Conventionally, epoxy resin mortar and polymer cement mortar have been used for repairing and reinforcing the deteriorated part of the concrete structure as described above. However, the epoxy resin mortar has various properties such as workability and pot life And it is hard to cure at low temperature due to high temperature dependency during curing. The thermal expansion coefficient is 2 to 4 times that of concrete, which causes a problem of deformation due to high temperature and high temperature. In addition, the polymer-cement mortar sold on the market has an excellent unity with the sphere as compared with the epoxy resin mortar, but has poor adhesion and compressive strength, resulting in a drop-off phenomenon. Also, when a thickener is added, a thickener is added to improve the adhesion. However, when the thickener is added, the surface of the transportation hose and the frictional force increase during the mechanical construction using the spray equipment, so that the hose is clogged, There are various problems such as deterioration.

Patent Registration No. 10-0643524 (November 11, 2006) Patent Registration No. 10-0995244 (Nov. 12, 2010) Patent Registration No. 10-0474665 (Feb. Patent Registration No. 10-1551842 (Feb.

The object of the present invention is to provide a mortar composition for preventing corrosion and freeze-thawing which can detoxify and deteriorate concrete deteriorated areas damaged by salt corrosion, freezing and thawing, and concrete, And to provide a repair method of a structural section.

The mortar composition for preventing salting and freezing and thawing according to the present invention and the maintenance method of the concrete structure damaged by the road side, neutralization, and chemical damage due to salting using the mortar composition of the present invention can remove deterioration parts of the concrete structure caused by salting and freeze- The mortar composition comprises 20 to 45 wt% of a cement component, 3 to 15 wt% of a hardwood material, 5 to 20 wt% of a mixed material, 25 to 20 wt% of a silica filler, A water-repellent agent 0.1 to 3.0 wt%, a water-repellent agent 0.1 to 3.0 wt%, a water-repellent agent 0.1 to 3.0 wt%, a water-repellent agent 0.1 to 3.0 wt% 0.2 to 2.0 wt% of a property improving material, and 0.005 to 1.0 wt% of graphene oxide.

The present invention has an excellent adhesion and compressive strength because the main material is composed of an inorganic system and has an effect of rapidly regenerating a deteriorated concrete structure.

The present invention is adapted to use a slag fine powder and a paper ash as a mixing material, and has an effect of improving anti-cracking and compressive strength.

In the present invention, the carbon nanotube mixed solution and the graphene oxide are added together, so that the fine pore structure is densified and water tightness and durability are enhanced. In addition, by improving tensile strength and adhesion strength, .

Since the present invention is applied to the existing concrete structure after removing about 5 cm of the deteriorated portion of the existing concrete, the amount of the industrial waste generated is reduced and the environmental pollution due to this is reduced.

Since the present invention has excellent adhesion strength, it is possible to omit the step of applying the old and new adhesives.

The present invention has water repellency and quick hardness, so that the repair work period is shortened, thereby allowing smooth passage of the vehicle.

FIG. 1 is an illustration showing a repairing process according to the present invention

The mortar composition for preventing salting and freezing and thawing according to the present invention comprises 20 to 45 wt% of a cement component, 3 to 15 wt% of a high hardwood, 5 to 20 wt% of a mixture, 25 to 55 wt% of a silica filler, 1.0 to 5.0 wt% of a latex, A water-repellent agent of 0.1 to 3.0 wt%, a property improving agent of 0.2 to 2.0 wt%, a graphene oxide of 0.1 to 3.0 wt%, a polymer resin of 0.5 to 4.0 wt%, a fluidizing agent of 0.2 to 2.0 wt%, an amorphous steel fiber of 0.01 to 0.8 wt% 0.005 to 1.0 wt%.

The cement component is a main component used for securing various mechanical strengths such as the compressive strength and the bending strength of the cured product, and the cement reacts with water to produce calcium hydrate and calcium aluminate hydrate, which are major hydration products, At this time, the mechanical strength is exhibited, and it becomes possible to use it as a material for construction and civil engineering for various purposes.

The cement can be used from one to five types of cement depending on the use of the repair concrete. Especially, in order to increase the resistance to calcium chloride used for solving freezing of sulphates and roads, 5 kinds of portland cement, It is effective to use slag cement or the like. In addition, crude steel cement or alumina cement may be used to quickly secure early strength due to the characteristics of the road.

The above-mentioned high hardness material may be an ettringite hydrate such that the main constituent mineral reacts with a calcium sulfoaluminate compound having C ₄ A ₃ , gypsum and CaO or Ca (OH) ₂ . Since the above-mentioned etchringite hydrate has a very fast reaction speed, it is possible to rapidly express the early strength of the cured product. Alumina cement, ultrahigh speed cement, crude steel cement can be used not only for the calcium sulphoaluminate and the gypsum but also for the hard material. If the content of the core material is less than 3 wt%, it fails to rapidly cure the concrete, and if it exceeds 15 wt%, the concrete is cured too rapidly, which makes it difficult to secure a predetermined time for the operation have.

The mixed material is used for enhancing the resistance to sulfate or calcium chloride and improving the air resistance by increasing the air volume of the concrete. Mixed powder in which slag powder, paper ash powder or slag powder and paper ash powder are mixed is preferably used A mixed powder in which slag powder and paper ash powder are mixed is used.

The slag powder not only improves long-term durability and chemical resistance, but also abundantly contains an aluminosilicate component, which improves the strength of concrete by virtue of its latent hydraulic properties.

The paper ash is a material generated as a by-product in a paper mill and is heat treated to have a blaine of about 4,000 to 7,000 (cm 2 / g). Since the paper ash has hydraulicity, calcium silicate hydrate (CaO-SiO ₂ -H ₂ O) or calcium aluminate hydrate (CaO-Al ₂ O) reacts with Ca (OH) ₂ hydrate produced by the reaction of cement with water. ₃ -H ₂ O) is produced, so that the structure of the cured body becomes dense, thereby enhancing the strength and improving the erosion resistance by the sulfate or calcium chloride.

When the paper ash is added in an amount of less than 5 wt%, it is not effective to increase the erosion resistance. When the paper ash is more than 20 wt%, not only the workability of the concrete mortar for repair is greatly reduced but also the mechanical property value such as compressive strength is decreased .

It is effective to use the above mixed materials in combination at a ratio of 5 to 20 wt%. That is, when the mixed material is added in an amount of less than 5 wt%, it is not effective to increase resistance to various kinds of salt, and when it is added in an amount exceeding 20 wt%, a mechanical property value of concrete such as compressive strength and bending strength is decreased. .

In particular, it is preferable that the slag powder and the paper ash are added at a mixing ratio of 1: 1 to 2. That is, the paper ash has excellent resistance to erosion by sulphate or calcium chloride, but has a problem of delaying early emphasis due to a slow reaction. However, when slag and paper ash are mixed at a weight ratio of 1: 1 to 2 , The reaction of the slag proceeds first before the reaction of the paper ash, and the strength enhancement is maintained.

In addition, since the paper ash has a problem that the fluidity is lowered as the addition amount is increased, the fluidity is improved when the slag and the paper ash are mixed in the weight ratio of 1: 1 to 2.

The silica filler is mixed with the silica sand of No. 5 and the silica sand of No. 6 and since the workability of the maintenance concrete tends to decrease as the silica sand ratio of No. 6 increases, 60 wt%, and silica powder having a No. 5 grain size of 60 to 40 wt%.

The latex has an effect of increasing the fluidity of the pre-hardening concrete, improving the workability, and improving the surface adhesion strength, bending strength, water tightness, freeze-thaw resistance, etc. after curing. The latex may be added with powder or liquid latex, preferably a liquid latex composed of 47 to 50 wt% of SB (Styrene-Bytaduebe) latex solid and 50 to 53 wt% of water.

When the latex is added in an amount less than 1.0 wt%, the adhesive strength is decreased. When the latex is added in an amount exceeding 5.0 wt%, the possibility of material separation is high. Therefore, the latex is added in an appropriate range, preferably 1.5 to 3.5 wt% .

The carbon nanotube mixture may be an epoxy resin, an SB latex resin, or a silicone resin containing 70 to 99.9 wt% of carbon nanotubes and 0.1 to 30 wt% of carbon nanotubes added and dispersed therein.

The carbon nanotubes have a tensile strength of 11 to 63 GPa and a modulus of elasticity of 300 to 1,000 g / m < 2 >. The carbon nanotubes are prepared by adding a multi-walled carbon nanotube having a cylindrical tube structure to a graphite sheet Is added.

Such carbon nanotubes reduce the microcracks in the concrete composition while reducing the porosity of the nanoparticles coated with the C-S-H gel to less than 50 nm, thereby slowing the generation of cracks.

The SB latex or the epoxy resin or the silicone resin improves the dispersibility of the carbon nanotubes and improves the early strength development and durability of the mortar composition.

In addition, the carbon nanotube mixed solution may be one that improves the dispersibility by ultrasonic treatment. At this time, the ultrasonic treatment is performed by ultrasonic wave crusher having a maximum power of 700 to 750 W for 3 to 10 seconds at an output amplitude of 40 to 60%, and then the process of stopping for 10 to 20 seconds is performed for 30 to 200 minutes, Repeat for 60 to 180 minutes.

The mortar composition to which the ultrasonic treated carbon nanotube mixture is added has a strength improvement of about 10 to 15% in the compressive strength and the flexural tensile strength in comparison with the mortar composition to which the untonerated carbon nanotube mixture is added Effect. That is, since the ultrasound-treated carbon nanotube dispersion can exhibit strength by incorporation of a small amount of carbon nanotubes, the carbon nanotube mixture may contain 90 to 99.9 wt% of epoxy resin, SB latex resin or silicone resin, 0.1 to 10 wt% of nanotubes may be added and dispersed.

In particular, it is more preferable that the ultrasound-treated carbon nanotube dispersion liquid contains carbon nanotubes in the epoxy resin.

The graphene oxide is used for enhancing the watertightness and durability of the concrete composition and may be selected from the group consisting of epoxy, hydroxyl, lactone, lactol, ketone, ester, a carbon material having a tensile strength of 15 to 45 GPa and an elastic modulus of 50 to 220 MPa can be used.

That is, the graphene oxide is in the form of an epoxy, hydroxyl, lactone, lactol, ketone, ester, or carboxylic acid group And graphene oxide, preferably in the form of an epoxy group, is incorporated.

The graphene oxide in the epoxy group form interacts with the carbon nanotube dispersion containing the carbon nanotubes in the epoxy resin to further improve the dispersibility and the strength enhancement effect.

That is, it is preferable that the carbon nanotube dispersion containing the carbon nanotubes in the epoxy resin and the graphene oxide in the epoxy group form are added to the epoxy resin, and most preferably, the carbon nanotubes are contained in the epoxy resin, Nanotube dispersions and graphene oxide in the form of epoxy groups are added.

When the graphene oxide is incorporated in an amount of 0.05 wt% or more, the volume of the C-S-H gel pores is increased by 2 to 2.5 times, so that the microporous structure of the concrete becomes loose and is effective in controlling the generation of concrete cracks. In addition, the compressive strength and the bending strength are also increased, so that the durability is improved. When the graphene oxide is incorporated in an amount exceeding 1 wt%, the slump value is reduced and it becomes difficult to ensure the workability.

 The polymer resin is added to increase the adhesion without being greatly influenced by the condition of the base surface made of concrete or concrete. It is an acrylic resin, an EVA resin, a polyvinyl alcohol resin, a methyl methacrylate resin, a vinyl acetate resin, a SBR resin Etc. may be used.

When the polymer resin is added in an amount of less than 0.5 wt%, it has no significant effect on the improvement of the adhesive strength. When the polymer resin is added in an amount exceeding 4.0 wt%, the strength of the cured product is considerably lowered and the viscosity of the concrete is increased. A problem that a clean finishing work becomes difficult becomes a problem.

The fluidizing agent is added to improve the workability of the maintenance concrete and to reduce the mixing water, and one or two melamine-based, naphthalene-based and carboxyl-based fluidizing agents may be used in combination.

When the fluidizing agent is added in an amount less than 0.2 wt%, the effect of improving the fluidity is weak. Therefore, the mixed water is used in a large amount, causing a decrease in the compressive strength and the bending strength. When the fluidizing agent is added in an amount exceeding 2 wt% But also causes separation of materials and the like.

The amorphous steel fiber is used to increase the resistance to cracking of the concrete composition. The amorphous steel fiber can control cracking of the concrete as the length of the amorphous steel fiber increases. However, the resistance to chlorine ion permeability may be lowered. The tensile strength and the degree of enhancement of the tensile strain are different. Therefore, a length of 10 to 50 mm, a thickness of 10 to 80 m, a width of 1 to 5 mm, and an aspect ratio of 100 to 300 is used. For example, when a material having an aspect ratio of less than 100 is used, the tensile strength and the tensile strain are remarkably lowered.

The water repellent material is added so as to have a function of preventing various deterioration of the structure caused by penetration of water into the cured product after the concrete is cured. That is, the water-repellent material is added for the purpose of blocking water or various harmful substances from penetrating into the cured body or blocking deterioration caused by freezing water in the winter season, and liquid phase or powder such as metal stearate, oleic acid, , Preferably stearate is used. In addition, the stearate may be a metal salt or a calcium salt or a sodium salt.

When the water-repellent material is added in an amount less than 0.1 wt%, the effect of reducing the internal diffusion of water is insignificant. When the water-repellent material is added in an amount exceeding 3.0 wt%, the mixing property of the cement decreases, A phenomenon of reduction occurs.

The property improving agent is added for the purpose of controlling the reaction rate and the water retentivity of the repair concrete. It is preferable that the property improving agent is added to 2 to 4 kinds of components such as citric acid, sodium gluconate, tartaric acid, silicic acid salt, methylcellulose, ethylcellulose and boric acid May be added in combination.

When the characteristics improving agent is added in an amount less than 0.2 wt%, there is no influence on the control of the reaction rate. When the property improving agent is added in an amount exceeding 2 wt%, the setting time of the repair concrete becomes very slow.

The mortar composition of the present invention as described above can be used not only for the maintenance of a section of a concrete structure but also for maintenance of a road section. In addition, the mortar composition according to the present invention is not limited to the salt and freeze-thaw prevention, but can be applied to the repair work of the deteriorated part of the concrete structure caused by various causes.

Hereinafter, a method for repairing a section of a concrete structure damaged by road surface, neutralization, or chemical damage due to salting using the mortar composition as described above will be described.

1 is a view illustrating an example of a repairing process according to the present invention. The concrete repairing method of a concrete structure using a mortar composition for preventing salting and freezing and thawing according to the present invention is characterized in that deterioration of a concrete structure The mortar composition for preventing salting and freezing and thawing is applied after applying a new and adhesive agent.

That is, in the section repair method according to the present invention,

A surface treatment step in which the deteriorated portion of the concrete structure 100 is removed;

A step of installing a reinforcing supporting metal material 10 on the surface protecting part 110 of the concrete structure after the surface treatment step;

And a mortar applying step of applying a mortar composition (20) for preventing salting and freezing and thawing to the surface protecting part (110) of the concrete structure.

In addition, the present invention may further include a step of removing the foreign matter on the surface protecting part and applying an adhesive to which the old and new adhesives 30 are applied, after the metal fitting step.

The present invention may further include a finishing step of finishing the surface with the ceramic coating material 40 after the surface protecting step.

The surface treatment step is a step of removing the cover material from the surface concrete caused by salt freezing, freezing and thawing, the exposure of the coarse aggregate, the concentration of the water puddle, the contamination of the greenery, the excavation site and the corrosion, and the surface of the deteriorated concrete structure is crushed by a tool Lt; / RTI > In addition, foreign matter to the surface protecting portion from which the deteriorated portion is removed is removed.

In the steel fixing step, after the deteriorated portion is removed by chipping, the surface protecting portion is pierced by a tool such as a drill, and then an attachment reinforcing supporting metal is installed.

The adhesive applying step removes a foreign matter on the surface protecting portion provided with the attachment reinforcing support metal by the high pressure washing water. At this time, a high-pressure scrubber of 100 to 150 kg / m < 2 > Further, when foreign matter is completely removed, using, for example, roller or brush coating work or an air spray gun is applied uniformly by impregnating the old and the new adhesive stock solution as 0.32㎏ _f / ㎠.

The mortar applying step is a step of applying the mortar composition for preventing salting and freezing and thawing according to the present invention, namely 20 to 45 wt% of cement, 3 to 15 wt% of a hardwood material, 5 to 20 wt% of a mixed material, 25 to 55 wt% of a silica filler, 1.0 to 5.0 wt% By weight of carbon nanotube mixture, 0.5 to 4.0% by weight of polymer resin, 0.2 to 2.0% by weight of fluidizing agent, 0.01 to 0.8% by weight of amorphous steel fiber, 0.1 to 3.0% by weight of water repellent agent, 0.2 to 2.0% , And 0.005 to 1.0 wt% of graphene oxide is applied to the mortar composition for preventing corrosion and freeze-thaw.

At this time, the mortar composition for preventing salting and freezing and thawing is applied 1.5 cm once by hand finishing or the like and applied twice over 3 cm (66.2 kg / m 2 when 3 cm is applied).

Hereinafter, the present invention will be described in detail by way of examples.

Example 1

, 9 wt% of papermaking ash (blaine 4,000 ~ 7,000 ㎠ / g), silica filler (No. 5), 8 wt% of cement (portland cement), 8 wt% of hardwood (ettringite hydrate), 9 wt% of slag powder, (Naphthalene-based) polymer resin (polyvinyl alcohol-based), 0.2 wt% of carbon nanotubes mixture, 2.8 wt% of latex (solid content 48 wt% A mortar composition composed of 1.0 wt% of amorphous steel fiber, 0.4 wt% of amorphous steel fiber, 0.98 wt% of water repellent material (metal stearate), 0.8 wt% of a property improving agent (methylcellulose: ethylcellulose = 1: 1) and 0.02 wt% of graphene oxide The compressive strength, the compressive strength ratio after immersion in 30% aqueous calcium chloride solution, the water absorption coefficient and the chloride penetration resistance test were measured and the results are shown in Table 1. At this time, the mixture of carbon nanotubes was prepared by dispersing 92 wt% of epoxy resin and 8 wt% of carbon nanotubes.

The above tests were carried out in accordance with various quality test methods of polymer cement concrete for repairing concrete structures specified in KS F 4042, and the prepared mortar products were researched in Korea.

[Table 1]

Example 2

, Silica filler (No. 5), cement (portland cement) 25.8 wt%, high hardwood (ettringite hydrate) 8 wt%, slag powder 6 wt%, paper ash (powder blaine 4,000-7,000 cm2 / g) (Naphthalene-based) polymer resin (polyvinyl alcohol-based), 0.2 wt% of carbon nanotubes mixture, 2.8 wt% of latex (solid content 48 wt% A mortar composition composed of 1.0 wt% of amorphous steel fiber, 0.4 wt% of amorphous steel fiber, 0.98 wt% of water repellent material (metal stearate), 0.8 wt% of a property improving agent (methylcellulose: ethylcellulose = 1: 1) and 0.02 wt% of graphene oxide The adhesive strength, compressive strength and compressive strength ratio after immersion in 30% aqueous calcium chloride solution were measured, and the results are shown in Table 2. At this time, the mixture of carbon nanotubes was prepared by dispersing 92 wt% of epoxy resin and 8 wt% of carbon nanotubes.

Example 3

, Silica filler (No. 5), cement (portland cement) 25.8 wt%, high hardwood (ettringite hydrate) 8 wt%, slag powder 6 wt%, paper ash (powder blaine 4,000-7,000 cm2 / g) (Naphthalene-based) polymer resin (polyvinyl alcohol-based), 0.2 wt% of carbon nanotubes mixture, 2.8 wt% of latex (solid content 48 wt% A mortar composition composed of 1.0 wt% of amorphous steel fiber, 0.4 wt% of amorphous steel fiber, 0.98 wt% of water repellent material (metal stearate), 0.8 wt% of a property improving agent (methylcellulose: ethylcellulose = 1: 1) and 0.02 wt% of graphene oxide The adhesive strength, compressive strength and compressive strength ratio after immersion in 30% aqueous calcium chloride solution were measured, and the results are shown in Table 2.

At this time, the carbon nanotube mixture was ultrasonically treated for 5 seconds at an output amplitude of 50% by using an ultrasonic wave crusher with a maximum power of 750 W, mixed with 92 wt% of epoxy resin and 8 wt% of carbon nanotube, and then stopped for 15 seconds. Min, were sonicated.

Example 4

, Silica filler (No. 5), cement (portland cement) 25.8 wt%, high hardwood (ettringite hydrate) 8 wt%, slag powder 6 wt%, paper ash (powder blaine 4,000-7,000 cm2 / g) (Naphthalene-based) polymer resin (polyvinyl alcohol-based), 0.2 wt% of carbon nanotubes mixed solution, 2.8 wt% of latex (solid content 48 wt% The compressive strength, the compressive strength and the tensile strength were measured for a mortar composition composed of 1.0 wt% of an amorphous steel fiber, 0.4 wt% of an amorphous steel fiber, 0.98 wt% of a sponge material (metal stearate) and 0.8 wt% of a property improving agent (methylcellulose: ethylcellulose = 1: The compressive strength ratios after immersion in a 30% aqueous solution of calcium chloride were measured and the results are shown in Table 2. At this time, the mixture of carbon nanotubes was prepared by dispersing 92 wt% of epoxy resin and 8 wt% of carbon nanotubes.

[Table 2]

As shown in [Table 2] above, the mortar composition for preventing salting and freezing and thawing according to the present invention is superior in compressive strength and adhesion strength, which are physical property values, as compared with the contrast group (commercial mortar composition for commercial sale) Durability-related water absorption coefficient and chloride ion penetration resistance test result showed very good effect. Particularly, the mortar composition for preventing corrosion and freeze-thawing according to the present invention shows excellent compressive strength ratio measured after immersion in an aqueous solution of calcium chloride.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims and their equivalents. Of course, such modifications are within the scope of the claims.

(10): Attachment strengthening support hardware
(20): Mortar composition for preventing salting and freeze-thawing
(30): Adhesive
(40): Ceramic coating material

Claims (10)

A mixture of 20 to 45 wt% of a cement component, 3 to 15 wt% of a high hardwood, 5 to 20 wt% of a mixed material, 25 to 55 wt% of a silica filler, 1.0 to 5.0 wt% of a latex, 0.01 to 0.3 wt% of a carbon nanotube mixed solution, %, A fluidizing agent of 0.2 to 2.0 wt%, an amorphous steel fiber of 0.01 to 0.8 wt%, a water repellent agent of 0.1 to 3.0 wt%, a property improving agent of 0.2 to 2.0 wt% and a graphene oxide of 0.005 to 1.0 wt%
The carbon nanotube mixture is prepared by adding and dispersing 0.1 to 30 wt% of carbon nanotubes to 70 to 99.9 wt% of an epoxy resin, an SB latex resin or a silicone resin,
Wherein said graphen oxide is graphen oxide in the form of an epoxy group.
The method of claim 1,
Wherein the mixed material is a mixed powder in which the slag powder and the paper ash powder are mixed,
Wherein the paper ash has a blaine of 4,000 to 7,000 (㎠ / g) as a powder.
The method of claim 2,
Wherein the slag powder and the paper ash are mixed at a weight ratio of 1: 1 to 2.
The method of claim 1,
The core material is an ettringite hydrate,
The silica filler is composed of 40 to 60 wt% of silica sand having a particle size of 6 and 60 to 40 wt% of silica sand having a particle size of 5,
The latex is a liquid latex composed of 47 to 50 wt% of a solid content of SB (Styrene-Bytaduebe) latex and 50 to 53 wt% of water,
The fluidizing agent is composed of one or two melamine-based, naphthalene-based, and carboxyl-based fluidizing agents,
The water repellent material is composed of a metal stearate or oleic acid or silane,
Characteristics improving agent A mortar composition for preventing salting and freeze-thawing, which comprises 2 to 4 kinds of components selected from the group consisting of citric acid, sodium gluconate, tartaric acid, silicofluoride, methylcellulose, ethylcellulose and boric acid.
delete The method of claim 1,
A carbon nanotube (Carbon Nano Tube) is added with a multi-walled carbon nanotube, and has a tensile strength of 11 to 63 GPa and an elastic modulus of 300 to 1,000 것이.
Characterized in that graphene oxide has a tensile strength of 15 to 45 GPa and an elastic modulus of 50 to 220 MPa.
The method according to claim 1,
The carbon nanotube mixture is ultrasonically treated with an ultrasonic wave crusher having a maximum power of 700 to 750 W for 3 to 10 seconds at an output amplitude of 40 to 60% and then stopped for 10 to 20 seconds for 30 to 200 minutes. By weight based on the weight of the mortar composition.
delete The method of claim 1,
Wherein the amorphous steel fiber has a length of 10 to 50 mm, a thickness of 10 to 80 m, a width of 1 to 5 mm, and an aspect ratio of 100 to 300.
A surface treatment step of removing a deteriorated portion of the concrete structure;
After the surface treatment step, a hard metal installation step in which an adhesion strengthening supporting metal material is installed on the surface protecting part of the concrete structure;
And a mortar applying step of applying a mortar composition according to any one of claims 1, 2, 3, 4, 6, 7, and 9 to the surface protecting part of the concrete structure. Repair Method of Concrete Structures Damaged by Road Side, Neutralization, and Chemical Damage due to Salt Damage by Freezing and Melting Mortar Composition.

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