KR102700620B1 - Penetrating monomer anti-carbonation agent for concrete surface coating and concrete surface treating method for caisson using thereof - Google Patents

Abstract

According to the invention, a concrete surface penetrating monomer anti-carbonation agent is provided, which comprises 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 5 to 8: 2 to 5; and an anti-absorption mixture in which 4 to 25 parts by weight of alkyltriethoxysilane, 0.3 to 15 parts by weight of nitrite, and 0.01 to 0.1 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, wherein the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:0.8 to 1:1.5 to produce a one-component type.

Description

{Penetrating monomer anti-carbonation agent for concrete surface coating and concrete surface treating method for caisson using its}

The present invention relates to a concrete surface penetrating monomer anti-carbonation agent, which prevents carbonation such as freezing, erosion and corrosion of reinforcing steel on the concrete surface of an apartment building, and more specifically, to a concrete surface penetrating monomer anti-carbonation agent, which forms an anti-carbonation layer on the concrete surface of an apartment building and provides a protective coating using a penetrative mixture having excellent penetrability and an anti-absorption mixture having excellent anti-absorption, thereby preventing the concrete surface of an apartment building from being neutralized, deteriorated and carbonated, thereby shortening its lifespan due to freezing, erosion and corrosion of reinforcing steel, and a concrete surface treatment method of an apartment building using the same.

In general, the performance degradation due to the deterioration of durability of multi-family housing such as apartments and villas requires considerable costs for repairs, reinforcement, and maintenance, and if a collapse occurs, the ripple effects will not only provide a factor that promotes anxiety about the country and those with knowledge beyond the economic and technical dimensions, but also lead to weakening competitiveness and loss of credibility in the international community.

Therefore, the recent domestic construction environment is changing from new investment to maintenance and repair/reinforcement for performance improvement of existing facilities, and interest in maintenance and life extension of facilities has been rapidly increasing in order to efficiently manage existing facilities and prevent duplicate investment of budget.

In addition, due to recent developments in construction technology, apartments and villas are becoming larger and taller, and there is a growing tendency to place importance on the exterior appearance, along with the functionality of the apartment itself, and the harmony with the surrounding environment.

However, the concrete surface of apartment buildings is easily contaminated by various external factors, causing damage or destruction of the exterior.

Therefore, damaged concrete surfaces must be properly repaired and reinforced to restore their original function, depending on the degree of damage. Accordingly, development of repair and reinforcement methods and materials for concrete surfaces is actively underway.

Among the maintenance methods for the concrete surface as mentioned above, the most commonly used method is to paint the concrete surface to ensure durability and watertightness against water leakage and cracking in large structures, and mainly, resin-based paints such as epoxy, urethane, and fluororesin, as well as organic paints, are widely used.

However, in the case of the resin type, since most of them are polymer series and have large molecular mass, there is a problem that they do not penetrate deeply into the concrete surface, and if the coating layer is removed due to surface lifting or impact, the concrete begins to deteriorate again.

In addition, in the case of organic systems, although they have excellent adhesion to the concrete surface, they have poor breathability and there is a problem that they gradually peel off from the surface over time due to shrinkage and expansion depending on temperature.

(Patent Document 0001) Registered Patent 10-1215403

(Patent Document 0002) Registered Patent 10-0192201

(Patent Document 0003) Registered Patent 10-0884015

(Patent Document 0004) Registered Patent 10-0949548

Accordingly, the purpose of the present invention is to provide a concrete surface penetrating monomer anti-carbonation agent capable of forming an anti-carbonation layer on the concrete surface of an apartment building through an anti-absorption composition having a reactor or reaction time that allows a low molecular inorganic compound having a small molecular mass and small particle size to be rapidly penetrated deep into the concrete surface of an apartment building by using a penetrating mixture and ensuring anti-absorption of water or chloride ions, considering the penetration depth and hardening time of the penetrating mixture, and a concrete surface treatment method of an apartment building using the same.

Meanwhile, the purpose of the present invention is not limited to the purpose mentioned above, and other purposes not mentioned can be clearly understood by those with ordinary skill in the art from the description below.

According to the invention, a concrete surface penetrating monomer anti-carbonation agent is provided, which comprises 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 5 to 8: 2 to 5; and an anti-absorption mixture in which 4 to 25 parts by weight of alkyltriethoxysilane, 0.3 to 15 parts by weight of nitrite, and 0.01 to 0.1 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, wherein the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:0.8 to 1:1.5 to produce a one-component type.

Here, lithium silicate preferably has a molar ratio of silicic acid and lithium of 1:2 to 1:4, potassium silicate preferably has a molar ratio of silicic acid and potassium of 1:4 to 1:6, and lithium silicate and potassium silicate preferably each have particles of 10 nm in size.

In addition, it is preferable that the concrete surface penetrating monomer anti-carbonation agent further includes 3 to 10 parts by weight of a carton, which is a catalyst or accelerator, based on 100 parts by weight of the penetrating mixture.

Meanwhile, according to the present invention, a method for treating the concrete surface of an apartment building using a concrete surface penetrating monomer anti-carbonation agent is provided, which comprises a step of cleaning and treating the concrete surface of an apartment building; and a step of penetrating and coating the concrete surface of the apartment building with the concrete surface penetrating monomer anti-carbonation agent as described above.

Therefore, according to the present invention, a low molecular inorganic compound having a small molecular mass and particle size is used as a penetrative mixture so as to rapidly penetrate deep into the concrete surface of an apartment building, and an anti-absorption mixture having a reactor or reaction time so as to secure anti-absorption properties by considering the penetration depth and hardening time of the penetrative mixture can form an anti-carbonation layer on the concrete surface of an apartment building.

In addition, it is possible to prevent moisture or foreign substances from being absorbed on the concrete surface of an apartment complex, thereby lowering the moisture content of the concrete, preventing neutralization or carbonation, and minimizing contamination, thereby increasing the lifespan of the apartment complex.

Meanwhile, the effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those with ordinary skill in the art from the description of the claims.

Hereinafter, preferred embodiments of the present invention will be described in detail.

A concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention comprises a penetrating mixture in which lithium silicate and potassium silicate are mixed in a predetermined volume ratio, and an anti-absorption mixture to which alkyl triethoxysilane, nitrite, and chloride are added, and the penetrating mixture and the anti-absorption mixture are mixed.

More specifically, the concrete surface penetrating monomer anti-carbonation agent of the present invention comprises 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 5 to 8: 2 to 5, and an anti-absorption mixture in which 4 to 25 parts by weight of alkyltriethoxysilane, 0.3 to 15 parts by weight of nitrite, and 0.01 to 0.1 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, and the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:0.8 to 1:1.5 to produce a one-component type.

Lithium silicate, together with potassium silicate, is homogeneously dispersed in a state of rapid penetration deep into the concrete surface or pores of apartment buildings, thereby improving the density, durability, and waterproofness of concrete, preventing neutralization or carbonation of the concrete surface, and suppressing elastic deformation.

Here, lithium silicate has a molar ratio of silicic acid and lithium of 1:2 to 1:4. If the molar ratio is less than 1:2, silicic acid is not sufficiently added, so that the effect of improving the strength of the concrete is not sufficiently secured, resulting in reduced durability and waterproofing, and if the molar ratio exceeds 1:4, an overreaction occurs on the surface of the concrete, granules are generated, which hinders uniform penetration and causes deoxidation or formation of sediments, resulting in defects. Therefore, it is preferable to have the molar ratio as above.

Potassium silicate, together with lithium silicate, penetrates deeply and quickly into the concrete surface or pores of apartment buildings to enhance the strength of concrete, increase surface hardness, prevent cracking, and improve chemical resistance, thereby preventing neutralization or carbonation of the concrete surface and ensuring sufficient adhesion when coating the concrete surface with an anti-absorption mixture.

Here, potassium silicate has a molar ratio of silicic acid and potassium of 1:4 to 1:6. If the molar ratio is less than 1:4, potassium is applied excessively and the silicic acid does not penetrate into the concrete, so that hardening takes a long time. If the molar ratio exceeds 1:6, the concrete is not sufficiently protected from moisture, durability is not improved, and defects are caused on the surface of the concrete. Therefore, it is preferable to have the molar ratio as above.

Meanwhile, lithium silicate and potassium silicate are used to manufacture a penetrative mixture that improves the strength and durability of concrete by forming bonds in the form of silicate lattice and calcium silicate through a silicate reaction, that is, a chemical interaction between silicate and calcium hydroxide and other substances in the concrete, when penetrating the concrete surface of an apartment building. More preferably, it is preferable that the mixture have particles of 10 nm in size so that they naturally penetrate the concrete surface even at a room temperature of 20℃ and react with calcium hydroxide and harden to form a gel.

Additionally, lithium silicate and potassium silicate are mixed in volume ratios of 5:5, 6:4, 7:3, and 8:2.

Here, lithium silicate and potassium silicate are added in a volume ratio of lithium silicate of at least 1 to 4 times that of potassium silicate. However, if the volume ratio of lithium silicate is less than 1 (for example, if lithium silicate and potassium silicate have a volume ratio of 4:6), there is a problem that the permeability is not secured and the material does not penetrate deeply enough into the concrete surface or pores but rather is discharged to the outside from the concrete surface. If the volume ratio of lithium silicate exceeds 4 times (for example, if lithium silicate and potassium silicate have a volume ratio of 9:1), the permeability is too strong and the material penetrates deeper than the unique material rejection point of the concrete surface, making it difficult to accurately evaluate the structural stability of the concrete surface and durability, and since the amount of potassium silicate added is small and the amount of silicate ions is insufficient, the material does not harden at room temperature, requiring a separate heat-curing means to deteriorate workability. Therefore, it is preferable to have a limited volume ratio as described above.

Alkyltriethoxysilane is used to improve the adhesion, durability and waterproofing of the anti-carbonation layer when manufactured as an anti-absorption mixture with nitrite and chloride and when penetrating or spraying it on the surface or pores of concrete. More preferably, it is good to have particles of 20 nm in size so that the penetrative mixture can penetrate into the micro-pores of concrete.

In addition, when alkyltriethoxysilane is manufactured as an anti-absorption mixture together with nitrite and chloride, the reaction period or reaction time of the anti-absorption mixture can be such that the penetrable mixture penetrates into the pores of the concrete surface to a predetermined depth and then hardens, while securing an anti-carbonation layer of a predetermined thickness, thereby maintaining waterproofing.

Here, alkyltriethoxysilane is added in an amount of 4 to 25 parts by weight per 100 parts by weight of the penetrating mixture. If it is less than 4 parts by weight, it is difficult to form an anti-carbonation layer with a sufficient thickness on the surface of the concrete, and it does not react with alkaline substances inside the concrete, thereby reducing the neutralization or anti-carbonation effect. If it exceeds 25 parts by weight, the pH value of the concrete increases, which has a negative effect on the formation of the anti-carbonation layer, and the penetrating mixture does not penetrate deeply into the pores of the concrete but is concentrated only on the surface. Therefore, it is desirable to have a limited weight part as described above.

When manufactured as an anti-absorption mixture with alkyltriethoxysilane and chloride, nitrite provides the function of promoting oxidation and reduction during a chemical reaction with calcium hydroxide after the penetrating mixture has penetrated into the pores of concrete, thereby promoting a chemical reaction between concrete and silicate penetrant through calcium ions, thereby forming calcium silicate on the concrete surface or in the pores.

Here, nitrite is added in an amount of 0.3 to 15 parts by weight per 100 parts by weight of the penetrative mixture. If it is less than 0.3 parts by weight, calcium and anions are insufficient, so that the silicate reaction does not occur smoothly. If it exceeds 15 parts by weight, a substance combined with calcium and anions precipitates in granule form or the reaction is concentrated on the concrete surface, so that the properties of the concrete change and the appearance deteriorates. Therefore, it is preferable to have a limited amount by weight as described above.

Chloride may be known as having the function of promoting penetration of a penetrable mixture, inducing neutralization, and improving the adhesion and durability of an anti-carbonation layer when manufactured as an anti-absorption mixture together with alkyltriethoxysilane and nitrite.

Here, chloride is added in an amount of 0.01 to 0.1 parts by weight per 100 parts by weight of the penetrating mixture. If it is less than 0.01 parts by weight, the silicate ions of the penetrating mixture cannot penetrate deeply into the pores of the concrete, so that the silicate reaction is reduced and the adhesion of the anti-carbonation layer is reduced. If it exceeds 0.1 parts by weight, it interacts with the reinforcing bars in the concrete, causing corrosion and reducing the penetrability and adhesion of the penetrating mixture. Therefore, it is preferable to have the weight parts as above.

Meanwhile, in the present invention, it is preferable that the concrete surface penetrating monomer anti-carbonation agent is added with 3 to 10 parts by weight of CaCl2·2H2O, which is a catalyst or accelerator that has permeability and water or chloride ion absorption prevention properties when forming an anti-carbonation layer through a penetrative mixture and an anti-absorption mixture, so that a chemical reaction between the concrete and the silicate penetrating material is promoted through calcium ions, thereby forming calcium silicate on the concrete surface or in pores.

Here, the carton is added in an amount of 3 to 10 parts by weight per 100 parts by weight of the penetrating mixture. If it is less than 3 parts by weight, the amount of calcium chloride is insufficient, so that the silicate reaction does not occur smoothly, the gelation of the penetrating mixture at room temperature (20°C) becomes difficult, and the moisture removal function and freezing point depression function are not sufficiently exerted. If it exceeds 10 parts by weight, the calcium chloride precipitates in the form of granules or the reaction is concentrated on the surface of the concrete, so that the properties of the concrete change and the appearance deteriorates. Therefore, it is preferable to have a limited weight part as described above.

Meanwhile, in the present invention, the penetrable mixture and the anti-absorption mixture are mixed in a volume ratio of 1:0.8 to 1:1.5 to manufacture a single-component type. However, if the volume ratio of the anti-absorption mixture is less than 0.8 with respect to the volume ratio of the penetrable mixture, the neutralization or anti-carbonation properties of the concrete surface are not sufficiently secured, so that the durability of the concrete is not improved. In addition, if the volume ratio of the anti-absorption mixture exceeds 1.5 with respect to the volume ratio of the penetrable mixture, a large amount of a composition such as chloride is added, so that the inside of the concrete is easily neutralized, and thus an abnormal chemical reaction may occur. Therefore, it is preferable to have a limited volume ratio as described above.

Hereinafter, the effect of a concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention will be described through specific examples.

A one-component concrete surface penetrating monomer anti-carbonation agent is manufactured by including 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 5:5, and an anti-absorption mixture in which 3 parts by weight of alkyltriethoxysilane, 0.1 parts by weight of nitrite, and 0.009 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, and the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:0.7.

A one-component concrete surface penetrating monomer anti-carbonation agent is manufactured by including 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 7:3, and an anti-absorption mixture in which 12 parts by weight of alkyltriethoxysilane, 6 parts by weight of nitrite, and 0.03 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, and the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:1.2.

A one-component concrete surface penetrating monomer anti-carbonation agent is manufactured by including 100 parts by weight of a penetrating mixture in which lithium silicate and potassium silicate are mixed in a volume ratio of 8:2, and an anti-absorption mixture in which 30 parts by weight of alkyltriethoxysilane, 20 parts by weight of nitrite, and 0.2 parts by weight of chloride are mixed based on 100 parts by weight of the penetrating mixture, and the penetrating mixture and the anti-absorption mixture are mixed in a volume ratio of 1:1.6.

Meanwhile, in order to evaluate the performance of the concrete surface penetrating monomer anti-carbonation agent of each of the above examples, test pieces were manufactured as described above, and then, using Company A's anti-carbonation agent as a comparative example, the freeze-thaw resistance through KSF 2456, the surface peeling resistance through ASTC 672, the chloride ion penetration resistance through KSF 2711, and the curing time at room temperature and the water absorption resistance (water absorption amount after 5 hours of submerging the concrete sphere coated with the examples and comparative examples in water) were evaluated. The results are shown in Table 1 below.

Therefore, it can be seen that the concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention has excellent neutralization and anti-carbonation effects through excellent freeze-thaw resistance, surface peeling resistance, chloride ion penetration resistance, room temperature curing property, and water absorption resistance compared to conventional anti-carbonation agents, as shown in Table 1 above.

In addition, in order to evaluate the performance of the concrete surface penetrating monomer anti-carbonation agent of Example 2 among each of the above examples, test pieces were prepared as described above, and then, using a known epoxy/acrylic coating agent as a comparative example, penetration depth, UV protection, service life, chloride ion reduction and moisture absorption rate reduction effects, water vapor transmission rate, crack prevention, and deicing salt corrosion prevention, etc. were evaluated, and the results are shown in Table 2 below.

Therefore, it can be seen that the concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention provides excellent penetration depth, UV protection, chloride ion reduction and moisture absorption rate reduction, water vapor transmission rate, crack prevention, and deicing salt corrosion prevention effects compared to conventional epoxy/acrylic coating agents, as shown in Table 2 above.

Meanwhile, a concrete surface treatment method for an apartment building using a concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention is as follows.

First, the concrete surface of the apartment building on which the concrete surface penetrating monomer anti-carbonation agent is to be applied is cleaned and treated.

Here, cleaning of the concrete surface of the apartment building includes removing dust, contaminants, or oil attached to the concrete surface and smoothing out the protrusions of the surface to be constructed.

Thereafter, a concrete surface penetrating monomer anti-carbonation agent corresponding to the above examples is manufactured.

Thereafter, a concrete surface penetrating monomer anti-carbonation agent is applied or sprayed onto the concrete surface of the surface-treated apartment complex by means of a coating or spraying means, or is hardened after penetrating into the micropores, thereby completing the construction of an anti-carbonation layer on the concrete surface.

Here, the concrete surface penetrating monomer anti-carbonation agent is applied twice at 200 ml to 300 ml per unit area (m^2) of concrete of an apartment building through a low-pressure (75 kPa) automatic spray device. At this time, it is preferable that the working temperature be 20℃ and the relative humidity be 55%, and then the application be applied once more after curing for 7 hours.

Meanwhile, in order to measure the anti-carbonation performance of an apartment building in which an anti-carbonation layer was formed by a concrete surface penetrating monomer anti-carbonation agent corresponding to Example 2 as described above, various items were measured and the results are shown in Table 3 in comparison with the standard values.

Therefore, it can be seen that the concrete surface treatment method of an apartment building using a concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention has better performance than the standard values in terms of penetration depth, water absorption performance, water permeability performance, chloride ion penetration resistance performance, and flash point, as shown in Table 3 above.

Meanwhile, in order to measure the anti-carbonation performance of an apartment building in which an anti-carbonation layer was formed by a concrete surface penetrating monomer anti-carbonation agent corresponding to Example 2 as described above, items such as the absorption rate before and after coating the anti-carbonation layer and the compressive strength after an immersion test were measured, and the results are shown in Table 4.

Therefore, it can be seen that the concrete surface treatment method of an apartment building using a concrete surface penetrating monomer anti-carbonation agent according to a preferred embodiment of the present invention has superior performance in terms of compressive strength and water absorption after an immersion test after coating than before coating, as shown in Table 4 above.

Therefore, according to the present invention, a low molecular inorganic compound having a small molecular mass and particle size is used as a penetrative mixture so as to penetrate deeply and quickly into the concrete surface of an apartment building, and an anti-absorption mixture having a reactor or reaction time so as to secure anti-absorption property by considering the penetration depth and hardening time of the penetrative mixture can form an anti-carbonation layer on the concrete surface of an apartment building, and through this, the concrete surface of an apartment building can be prevented from being neutralized, deteriorated, and carbonated, thereby preventing its lifespan from being shortened by freezing, erosion, and corrosion of reinforcing steel.

Although the preferred embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms because various substitutions, modifications, and changes can be made without departing from the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims (4)

100 parts by weight of a penetrative mixture comprising lithium silicate and potassium silicate in a volume ratio of 5 to 8: 2 to 5;
Based on 100 parts by weight of penetrating mixture,
Contains an anti-absorption mixture containing 4 to 25 parts by weight of alkyltriethoxysilane, 0.3 to 15 parts by weight of nitrite, and 0.01 to 0.1 parts by weight of chloride.
A concrete surface penetrating monomer anti-carbonation agent characterized in that it is manufactured as a single-component type by mixing a penetrating mixture and an anti-absorption mixture in a volume ratio of 1:0.8 to 1:1.5. In the first paragraph,
Lithium silicate has a molar ratio of silicate and lithium of 1:2 to 1:4.
Potassium silicate has a molar ratio of silicic acid and potassium of 1:4 to 1:6.
A concrete surface penetrating monomer anti-carbonation agent characterized in that lithium silicate and potassium silicate each have particles of 10 nm in size. In the first paragraph,
Based on 100 parts by weight of penetrating mixture,
A concrete surface penetrating monomer anti-carbonation agent characterized by further containing 3 to 10 parts by weight of a catalyst or accelerator, CaCl2·2H2O. The stage where the concrete surface of the apartment building is cleaned and treated;
A method for treating the concrete surface of an apartment building using a concrete surface penetrating monomer anti-carbonation agent, characterized in that it comprises a step of penetrating and coating the concrete surface of an apartment building with a concrete surface penetrating monomer anti-carbonation agent according to any one of claims 1 to 3.