KR100448520B1 - Performance improver and it's manufacturing process treating surface for reinforcement concrete structures attacked by chloride penetration and carbonation - Google Patents

Abstract

The present invention is applied to the concrete structure once or several times the surface treatment performance improver prepared by mixing the highly reactive sodium silicate and the biochemical sodium alginate or casein without removing concrete spheres degraded due to salting or neutralization By fixing chloride ions in concrete and suppressing corrosion activity of reinforcing bars in the active state, the surface of reinforced concrete structures can improve the performance of structures by improving the pH of degraded concrete and strengthening concrete spheres. The present invention relates to a process type performance improving agent and a method for producing the same.

The present invention is a surface treatment type of reinforced concrete structure manufactured by mixing 15% to 70% by weight of sodium silicate as a main raw material, 0.05% to 5.0% by weight of biochemicals as a catalyst, and 25% to 84.05% by weight of distilled water. Provide performance improvers.

The present invention is Na ₂ O · 3SiO ₂ or Na ₂ O · 4SiO with a 0.05% ~5.0% by weight of alginic acid is selected to _215-70% by weight of sodium silicate selected from sodium caseinate, 25 parts by weight of distilled water A first step of maintaining the mixture at a predetermined temperature by stirring the% to 84.05% by weight; And a second step of dropwisely reacting acetic acid one drop at an interval of 1 to 5 hours so that the mixture is evenly mixed.

Description

Composition improver and it's manufacturing process treating surface for reinforcement concrete structures attacked by chloride penetration and carbonation

The present invention relates to a surface treatment type performance improving agent for reinforcing concrete structures corroded by salting and neutralization, and a method for manufacturing the same. In particular, the corrosion of reinforcing steel is generated by salting and neutralizing, and the performance of concrete is degraded. A performance improvement agent made by mixing sodium silicate and biochemicals on the surface of the structure is applied once or several times to infiltrate the active corrosive material of the reinforcement, and to stabilize the chloride ions in the concrete to promote corrosion of the steel. The present invention relates to a surface treatment type performance improving agent and a method of manufacturing the concrete structure that can suppress the corrosion promoting activity, as well as improve the pH of the degraded concrete to improve the durability of the concrete.

In general, salt salt refers to a phenomenon in which concrete structures are damaged by corrosion of reinforcing bars due to chloride penetration or presence in reinforced concrete structures. Cement is composed of tricalcium silicate (3CaO · SiO ₂ ), silicic acid lime (2CaO · SiO ₂ ), alumina trioxide (3CaO · Al ₂ O ₃ ) and iron aluminate (4CaO · Fe ₂ O ₃ · Al ₂ O ₃ ) is the main component, of which tricalcium silicate and disilicate silicate are the main compounds, accounting for about 75% of the cement, and calcium silicate hydrate and calcium hydroxide [Ca (OH ₂ )] by hydration. At this time, the produced calcium hydroxide occupies about 24% of the cement, so that the pH of the concrete is 12 to 13 strong alkali. Under such strong alkali, the reinforcing bar is not corroded by forming a thin passivation film (ferrous hydroxide, γ-Fe ₂ O ₃ · nH ₂ O) having a thickness of 20 to 60 kPa on the surface. However, when chloride enters concrete and chloride ion (Cl ⁻ ) increases above a certain value, the reinforcing steel in the concrete partially corrodes. The red rust generated by the corrosion expands to about 330kgf / ㎠ The expansion pressure causes the concrete to crack. Corrosion of reinforcing steel is developed in the form of ferric hydroxide [Fe (OH) ₂ ] with low water solubility by the electrochemical combination of oxygen (O ₂ ) and water (H ₂ O). Fe (OH) ₂ develops into Fe (OH) ₃ and forms a relatively stable form of Fe ₂ O ₃ by continuous corrosion.

On the other hand, since chloride invades concrete, the potential difference occurs because it is not constantly present over the entire part of the rebar, and typically the top layer of the reinforcing bar is activated fastest and leads to corrosion. The potential difference induces the flow of electrons to the reinforcing bars, as well as the electrochemical reactions on the surface of the reinforcing bars, which are promoted by chloride ions, leading to corrosion of the reinforcing bars.

On the other hand, neutralization means that erosive gases such as carbon dioxide (CO ₂ ) in the atmosphere diffuse to the surface of the concrete and cause carbonation reactions with Ca (OH) ₂ , which diffuses back in the concrete inner layer (calcium silicate hydrate immobilized in concrete). The gel also reacts in part, and the reaction of Ca (OH) ₂ is the main reaction) It is a phenomenon in which strong alkali (pH12.6) due to calcium hydroxide dissolved in the pore water of concrete is neutralized (pH8.3-10.0). If the neutralization of the concrete does not reach the reinforcing part, there is no problem in the durability of the concrete.However, if the neutralization reaches the reinforcing part, the corrosion resistance function of the internal reinforcing steel based on the strong alkalinity of the concrete is deteriorated, causing the problem of the breakdown of the passive film Corrosion of the rebar begins to develop when conditions for the simultaneous supply of water and oxygen are established.

The definition of concrete neutralization is considered from a chemical reaction point of view: "The cement calcium silicate hydrate gel produced by the hydration of cement and the by-product calcium hydroxide are erosive substances, such as erosive gases, such as carbon dioxide in the atmosphere, or sulphates in aqueous solution. It is a phenomenon in which mortar and concrete gradually lose their strong alkalinity from the surface layer, that is, the diffusion process of carbon dioxide into mortar and concrete with carbonation reaction with calcium hydroxide. Degradation of anticorrosive function for internal rebar based on the strong alkalinity of concrete. Usually, when the Falkland cement is fully hydrated, about 25 to 28% of calcium hydroxide is produced in terms of cement weight. Calcium hydroxide in concrete is dissolved in the pore water, but most of it is present as a solid, the pore solution is present as a saturated aqueous solution of calcium, and concrete exhibits a strong alkalinity of about pH 12.6 by the saturated aqueous solution of calcium hydroxide. In this strong alkali situation, since the passive film is formed on the surface of the internal reinforcing concrete, it remains stable against corrosion as long as chlorine ions are mixed and corrosion promoting factors do not penetrate from the outside. Calcium hydroxide and calcium silicate hydroxide gels in the concrete mainly produce carbonation reaction with carbon dioxide gas in the atmosphere, convert to calcium carbonate, and concrete gradually loses strong alkalinity from the surface. It is expressed as a neutralization phenomenon. The concentration of carbon dioxide in the atmosphere depends on environmental conditions, but it is generally around 0.035% outdoors and around 0.07% indoors. However, as fossil fuels such as petroleum and coal have increased in recent years, carbon dioxide concentrations tend to continue to increase. In other words, if the carbon dioxide concentration continues to increase due to this trend, problems may occur in the future even in structures that are not a problem for neutralization at present.

Therefore, in the case of internal reinforcing steel in concrete, Fe (OH) ₂ and Fe (OH) _{3, which} are primary or secondary corrosive materials of the rebar, are immobilized in the form of Fe ₂ O ₃ as a stable compound, and the activity of chloride ions is prevented. If suppressed, the corrosion of reinforcing bar can be suppressed, and the performance of concrete structure can be prevented if blocking the ingress of CO ₂ or improving the pH of degraded concrete and suppressing the corrosion activity of the reinforcing bar.

Until now, the repair method removes concrete parts that have degraded due to salt and neutralization, and undergoes cross-sectional recovery.However, the removal and damage of cross-sectional damaged concrete areas are time-consuming and expensive. In addition, there is a problem in that it is difficult to design the repair due to the unclear portion of the concrete removal target. As a part of overcoming the above problems, there is a method of blocking the supply of oxygen and water, which are corrosion factors of reinforcing bars, by using a highly waterproof surface coating agent, but this method inhibits the penetration of oxygen and prevents the supply of water and chloride ions. It has excellent performance in terms of blocking function, but has a reverse function of confining water and chloride ions in concrete, and thus impairs the corrosion of reinforcing bars.

Therefore, the present invention has been made in order to solve the above problems, prepared by mixing a highly reactive sodium silicate and sodium alginate or casein of biochemicals without removing concrete spheres degraded due to salt or neutralization Applying a surface treatment type performance improver to concrete structures once or several times to immobilize chloride ions in concrete, inhibit corrosion activity of reinforcing steel bars, improve pH of degraded concrete and reinforce concrete spheres It is an object of the present invention to provide a surface treatment type performance improving agent and a method of manufacturing the reinforced concrete structure that can improve the performance of the structure.

1 is a graph showing the results of the chloride immobilization effect experiment.

Figure 2 is a graph showing the results of the neutralization recovery experiment.

Figure 3 is a graph showing the pull strength demonstration results.

Figure 4 is a graph showing the experimental results of air permeability.

5 is a graph showing the results of permeability experiment.

Figure 6 is a graph showing the rebar corrosion potential test results.

In order to achieve the above object, the present invention, 15% by weight to 70% by weight of sodium silicate as a main raw material, 0.05% to 5.0% by weight of biochemicals as a catalyst, 25% to 84.05% by weight of distilled water prepared by mixing Provides a surface treatment type performance improving agent for concrete structures.

The present invention is Na ₂ O · 3SiO ₂ or Na ₂ O · 4SiO with a 0.05% ~5.0% by weight of alginic acid is selected to _215-70% by weight of sodium silicate selected from sodium caseinate, 25 parts by weight of distilled water A first step of heating and maintaining the mixed mixture by stirring% to 84.05% by weight at 70 to 100 ° C; And a second step of dropwisely reacting acetic acid one drop at an interval of 1 to 5 hours so that the mixture is evenly mixed.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

The surface treatment type performance improving agent and the manufacturing method thereof of the reinforced concrete structure according to the present invention is to peel off the part of the concrete structure damaged by salt and neutralization, and to penetrate the performance improving agent to the peeling site to suppress secondary corrosion of the reinforcement, Implemented to enhance the durability of the concrete sphere, the surface treatment type performance improving agent of the reinforced concrete structure of the present invention 15% to 70% by weight of sodium silicate of the water glass system as the main raw material, and a biochemical that acts as a catalyst In a mixture of 0.05% to 5.0% by weight of a selected material of sodium alginate or casein, and 25% to 84.05% by weight of distilled water, up to 3.0% by weight of a fluorine-based surfactant as a viscosity-lowering agent and up to 7.0% by weight of triethanolamine as a reinforcing corrosion inhibitor of NaOH or Ca (OH) ₂ together in order to allow the mixture to maintain the necessary pH13~14 My main component consisting of the alkali give 7.0 suggests an example joseonghan by the addition of% by weight.

In the composition, the catalyst is 0.05% by weight to 5.0% by weight because when it is 0.05% by weight or less, there is no effect as a performance improving agent for concrete surface treatment, and when it is 5.0% by weight or more, there is a problem that the penetration force is lowered due to high viscosity.

The sodium silicate is prepared by melting a pure sand and an alkali substance such as Na ₂ CO ₃ at a high temperature of 1300 ° C. and inserting a cullet into water and heating it at 1 to 2 atmospheres to obtain silicon (SiO ₂ ) molecules. It is a small unit polymer having about 10 to 20, and is also used as a mixed material of concrete and cement.

The Na ₂ O · 3SiO ₂ and Na ₂ O · 4SiO when the biochemical substance, such as sodium alginate molecular formula of 0.1 to 5% by weight of sodium silicate (sodium alginate) consisting of _two or casein (casein) to be mixed, the concrete of the It reacts with hydration products to form calcium sulferaluminates of low or high calcium, and combines with calcium hydroxide in concrete to form calcium silicate hydrate gel, which not only improves the durability of concrete, but also It was confirmed through long-term experimental studies that the permeation membrane was formed to improve the synchronicity and absorbed water to improve the waterproof performance of concrete. In other words, by the catalysis of sodium alginate and casein, sodium silicate in the form of Na ₂ O · nSiO ₂ reacts with calcium hydroxide in concrete to form mCaO · nSiO ₂ · mH ₂ O, where m and n are 3 It exists in the range of -10.

In addition, in the present embodiment, 0.5 to 5% by weight of an alkali donor such as sodium hydroxide (NaOH) or calcium hydroxide (Ca (OH) ₂ ) is mixed with a mixture of sodium silicate and a biochemical, thereby adjusting the pH of the preparation to 12 to 5. It was confirmed through experimental studies that after manufacturing with strong alkalinity of 14, when applied to the concrete, the concrete neutralization phenomenon was suppressed and the corrosion of the steel was suppressed by improving the pH of the concrete.

In addition, biochemicals such as sodium alginate and casein have been found to reduce the surface tension of the mixture containing sodium silicate to facilitate infiltration into concrete, and the mixture containing sodium silicate is catalyzed by the biochemical catalysis. a chloride ion penetration in the (Cl ^-) in the reaction by forming a silicate gel containing a sodium chloride (NaCl) was confirmed that a chloride ion acts to remove the chloride ions immobilized on the negative effects on corrosion promotion of reinforcement.

In addition, even when 0.5 to 5% by weight of triethanolamine (Triehanol amine) is added to the mixture to inhibit the corrosion of the reinforcing bars, sodium silicate-based mixture penetrates well into the concrete without lowering the penetration force, 2 of the primary corrosion Inhibition of secondary corrosion response was confirmed through research.

The present invention made of the composition as described above is diffused into the concrete by the capillary osmotic pressure of the concrete to fix the chloride ion in the concrete, inhibit the corrosion activity of the reinforcing steel in the active state, as well as improve the pH of the reduced concrete and concrete Strengthen the sphere to improve the performance of the structure.

The following describes the manufacturing method of the present invention.

First, sodium alginate with a molecular formula of C ₆ H ₇ NaO ₆ and casein with less than 15% by weight of milk fat extracted from milk have a very high viscosity and are not mixed with sodium silicate in a general environment. Do not. Therefore, 1 to 20 g of sodium alginate or casein are added to 100 to 500 g of sodium silicate having a molecular formula of Na ₂ O 3 SiO ₂ or Na ₂ O 4 SiO ₂ , and distilled water is charged so that the total amount is 900 g. At this time, when the sodium alginate or casein exceeds 20g per 900g of total amount, the viscosity and surface tension are high, making it difficult to penetrate concrete, and when it is 1g or less, it is difficult to act as a catalyst. Next, the mixture of sodium silicate and sodium alginate or casein is placed on a heating plate and the solution is kept at 70 to 100 ° C. and then stirred slowly. At this time, since the temperature of the solution is high, distilled water is evaporated when stirring for a long time, the watch glass should be covered on the stirring beaker, and when the amount of the solution is reduced, the total amount is replenished so that the total amount is 900g. In addition, since the biochemicals of sodium alginate or casein coagulate together with sodium silicate on the bottom of the stirring beaker, care should be taken in the stirring. The mixture of sodium silicate and sodium alginate or casein was continuously stirred for 1 to 2 hours on a heating plate at 70 to 100 ° C., and then acetic acid having a molecular formula of CH ₃ COOH was added to the dropper and then stirred for 1 to 5 hours. The reaction is carried out for 1 to 2 days while dropping 5 to 50 drops one by one at intervals. Here, 5-50 drops of acetic acid is added dropwise to the dropper solution to smoothly mix sodium silicate and sodium alginate or casein. When 50 drops or 10 g of the acetic acid is added, the pH of the entire mixture is increased. This can weaken the ability of surface treatment type performance improvers to contribute to the recovery of neutralization of concrete.

The viscosity of the mixture thus prepared is about 100 to 500 cps, where the molecular formula is C ₅ H ₈ SO ₂ Lif (C ₂ F ₄ ) _{3 to 8} or (C ₂ H ₄ O) _n HF (C ₂ F ₄ When 0.01 to 0.5% by weight of _3-8 fluorine-based surfactant is mixed and dispersed evenly, the viscosity of the mixture is lowered to 100 cps or less, thereby improving the penetration performance into concrete. To this, 1-5% by weight of triethanolamine of the molecular formula (C ₂ H ₅ ) ₃ NH, which is a reinforcing corrosion inhibitor, is added, and an alkali-impartant having NaOH or Ca (OH) ₂ as a main component as necessary is 0. If it adds-5 weight%, the surface treatment type performance improving agent is manufactured. The degree of addition of the alkali scavenger depends on the degree of neutralization of the concrete structure to improve the performance, but it is usually preferable to add in the range that the pH of the surface treatment type performance improving agent can maintain 13 to 14.

According to the present invention prepared as described above, after removing the peeling and dropping parts of the concrete spheres degraded by salting and neutralization with an air pressor, the surface treatment type performance improving agent is once or several times on the surface of the concrete spheres. After coating, water is sprayed by a sprayer at the time point 6 hours after the coating is applied for water supply, and the coating method at this time uses a roller or a brush.

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

Example 1

Sodium silicate, Na ₂ O 3 SiO ₂ , is 0%, 15%, 25%, 30%, 40%, 50%, 60%, 70% by weight, respectively. 0.1 wt% of sodium alginate, 0.1 wt% of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, and 1 wt% of triethanolamine as a reinforcing corrosion inhibitor were uniformly mixed to prepare the present invention. In the present embodiment, the sodium silicate is 0% by weight in order to compare the difference between when the sodium silicate is not added and when it is added. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 2

Sodium silicate, Na ₂ O. 4SiO ₂ , is 0% by weight, 15% by weight, 25% by weight, 30% by weight, 40% by weight, 50% by weight, 60% by weight, and 70% by weight, respectively. 0.1 wt% of sodium alginate, 0.1 wt% of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, and 1 wt% of triethanolamine as a reinforcing corrosion inhibitor were uniformly mixed to prepare the present invention. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 3

30% by weight of sodium silicate Na ₂ O 4 SiO ₂ , 0.1% by weight of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, and 1% by weight of triethanolamine as a reinforcing corrosion inhibitor. The present invention was prepared by mixing sodium alginate at 0 wt%, 0.05 wt%, 0.1 wt%, 0.5 wt%, 1.0 wt%, 3.0 wt%, 5.0 wt% and 7.0 wt%, respectively. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 4

30% by weight of sodium silicate Na ₂ O 4 SiO ₂ , 0.1% by weight of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, 1% by weight of triethanolamine as a reinforcing corrosion inhibitor The present invention was prepared by mixing 0%, 0.05%, 0.1%, 0.5%, 1.0%, 3.0%, 5.0%, and 7.0% by weight, respectively. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 5

C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 phosphorus in 30% by weight of sodium silicate Na ₂ O 4SiO ₂ , 0.1% by weight sodium alginate as biochemical, 1% by weight of triethanolamine as reinforcing corrosion inhibitor The present invention was prepared by mixing the surfactant at 0 wt%, 0.01 wt%, 0.05 wt%, 0.1 wt%, 0.3 wt%, 0.5 wt%, and 1.0 wt%, respectively. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 6

(C ₂ H ₄ O) _n HF (C ₂ F ₄ ) _{3 to} 30% by weight of sodium silicate of Na ₂ O 4 SiO ₂ , 0.1% by weight of sodium alginate as a biochemical, and 1% by weight of triethanolamine as a steel corrosion inhibitor. _The present invention was prepared by mixing the ₈ phosphorus surfactant at 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, and 1.0% by weight, respectively. This example was evaluated by measuring the chloride immobilization, pullout strength, air permeability and water permeability according to the method described below.

Example 7

30% by weight of sodium silicate, Na ₂ O 4 SiO ₂ , 0.1% by weight of sodium alginate as biochemical, 0.1% by weight of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, steel corrosion inhibitor The present invention was prepared by mixing NaOH as an alkali imparting agent in 1% by weight of triethanolamine at 0%, 0.5%, 1.0%, 2.0%, 3.0%, 5.0%, and 7.0% by weight, respectively. In this embodiment, the neutralization depth and pH were measured according to the method described below to compare and evaluate the degree of neutralization recovery.

Example 8

30% by weight of sodium silicate Na ₂ O 4 SiO ₂ , 0.1% by weight sodium alginate as biochemical, 0.1% by weight of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, triethanol as a reinforcing corrosion inhibitor The present invention was prepared by mixing Ca (OH) ₂ as an alkali imparting agent in 0% by weight, 0.5% by weight, 1.0% by weight, 2.0% by weight, 3.0% by weight, 5.0% by weight and 7.0% by weight of amine, respectively. . In this embodiment, the neutralization depth and pH were measured according to the method described below to compare and evaluate the degree of neutralization recovery.

Example 9

30% by weight of sodium silicate, Na ₂ O 4 SiO ₂ , 0.1% by weight of sodium alginate as biochemical, 0.1% by weight of C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 surfactant, NaOH as alkali granting agent The present invention was prepared by mixing triethanolamine as a reinforcing corrosion inhibitor in 0.5% by weight, respectively, in 0% by weight, 0.5% by weight, 1.0% by weight, 2.0% by weight, 5.0% by weight, and 7.0% by weight. In this embodiment, the rebar potential difference was measured and compared with and evaluated according to the method described below.

In the above first to ninth embodiments, the additive material is defined as 0 wt% to compare the difference between when the additive material is not added and when it is added.

Next, a characteristic test result of the present invention will be described with reference to FIGS. 1 to 6.

Figure 1 shows the results of the chloride immobilization effect test.

As shown in the figure, the chloride immobilization effect test was carried out for 28 days on the 305 × 305 × 76mm footnote concrete specimens, and then immersed in a 3.6% aqueous solution of 3.6% NaCl in accordance with AASHTO T259 for 90 days to chloride ions in the concrete It was allowed to penetrate. Then, the concrete specimens were dried for 7 days, and the sprinkling curing was performed for 7 days by applying the performance improving agent of the present invention to the concrete surface. And 40 g of samples were taken from the concrete surface to 45 mm, and the amount of water-soluble chlorides was measured using the ion electrode method.

As a result of applying the performance improving agent of the present invention to the concrete surface immersed in 3.6% aqueous NaCl solution for 90 days to examine the effect of sodium silicate, chloride concentration was reduced regardless of the type and amount of sodium silicate, especially silicic acid 40% by weight of sodium chloride showed the most significant effect of immobilization, sodium silicate Na ₂ O · showed that the Na ₂ O · 4SiO ₂ 3SiO ₂ is greater than the effect of chloride immobilized. In addition, the effect of the type and amount of biochemicals on chloride immobilization decreased the chloride concentration by adding biochemicals. Especially, the chloride immobilization effect was found to be greatest at about 1% by weight of biochemicals, and sodium alginate was higher than casein. The chloride immobilization effect was shown to be large. As described above, 40% by weight of sodium silicate, 1% by weight of biochemicals, and 0.3% by weight of surfactants were found to be most effective in chloride immobilization, and the performance of the present invention on concrete surfaces containing chloride ions therein under salt damage. It was found that the application of the modifier reduces the chloride ion concentration and is effective in preventing salts.

Figure 2 shows the results of the neutralization recovery experiment.

As shown in the figure, six 100 × 100 × 100 mm concrete test specimens subjected to 28 days of standard curing were placed in a chamber at a temperature of 30 ° C., a relative humidity of 60%, and a carbon dioxide concentration of 10% to facilitate neutralization for 90 days. Three specimens subjected to the neutralization promotion test were sprayed with phenolphthalein solution to measure the neutralization depth, and then the pH was measured for each concrete depth. As a result of applying the performance improving agent of the present invention to the concrete subjected to the neutralization acceleration test, up to 5% by weight of alkali-imparting agent, the higher the addition amount of the alkali-imparting agent, the lower the neutralization depth and the pH were increased. It was no longer shown to have a neutralizing recovery effect, and the alkali-imparting agent NaOH was shown to be more effective at recovering neutralization than Ca (OH) ₂ . As mentioned above, it was found that the alkaline imparting agent was most effective at 5% by weight to recover the neutralization, and when the performance improving agent of the present invention was applied to the neutralized concrete surface, it was found that the pH was increased to have an effect on re-alkalization of concrete. Could.

Figure 3 shows the pullout strength test results.

As shown in the figure, the 305 × 305 × 76mm footnote concrete specimens subjected to 28 days of standard curing were dried for 7 days, and then cured for 7 days by applying the performance improving agent of the present invention, followed by a pull-off test apparatus specified in ASTM D 4541. The concrete pullout strength of 10mm depth was measured. As a result of applying the performance improving agent of the present invention to the surface of concrete to examine the effect of sodium silicate, the pullout strength increased regardless of the type and amount of sodium silicate. , sodium silicate _{Na 2 O · Na 2 O ·} 4SiO 2 than the 3SiO ₂ showed the promoting effect of pull-out strength greater. In addition, the effect of the type and amount of biochemicals on the increase in the pullout strength was increased by adding biochemicals, and the pullout strength enhancement was the greatest at about 1% by weight of the biochemicals. In addition, the surfactant was found to have the greatest effect of enhancing the pullout strength at 0.3% by weight. As described above, 40% by weight of sodium silicate, 1% by weight of biochemicals, and 0.3% by weight of surfactants were most effective in improving the pullout strength, and the concrete surface strength was improved by applying the performance improving agent of the present invention to concrete. I could see that.

Figure 4 shows the experimental results of the air permeability.

As shown in the figure, the 305 × 305 × 76mm footnote concrete specimens subjected to 28 days of standard curing were dried for 7 days, cured for 7 days by applying the performance improving agent of the present invention, and then the concrete permeability was measured by a Torrent Permeability Tester. As a result of applying the performance improving agent of the present invention to the surface of concrete to examine the effect of sodium silicate, the number of permeability decreased regardless of the type and amount of sodium silicate. was, the sodium silicate is Na ₂ O · Na ₂ O · 4SiO ₂ than 3SiO ₂ showed a large increase water-tightness effect. In addition, the effect of the type and amount of biochemicals on the water-tightness-promoting effect was reduced by adding biochemicals, and the effect of reducing air permeability was the greatest at about 1% by weight of biochemicals. In addition, sodium alginate was shown to have a greater water-tightness-promoting effect than casein, and the surfactant showed the greatest water-tightness-promoting effect at 0.3% by weight. As mentioned above, 40% by weight of sodium silicate, 1% by weight of biochemicals, and 0.3% by weight of surfactants were most effective in improving the watertightness. As the performance improving agent of the present invention was applied to the concrete surface, the structure of concrete became dense. It can be seen that there is a significant effect in blocking foreign substances that adversely affect the concrete such as carbon dioxide gas, nitrogen gas, oxygen.

5 shows the results of permeability experiment.

As shown in the figure, the 305 × 305 × 76mm footnote concrete specimens subjected to 28 days of standard curing were dried for 7 days, cured for 7 days by applying the performance improving agent of the present invention, and then the permeability of concrete with the GWT permeability test apparatus. Sex was measured. As a result of applying the performance improving agent of the present invention to the concrete surface in order to examine the effect of sodium silicate, the coefficient of permeability was reduced regardless of the type and amount of sodium silicate. was, the sodium silicate is Na ₂ O · Na ₂ O · 4SiO ₂ than 3SiO ₂ showed a large increase water-tightness effect. In addition, the effect of the type and amount of biochemicals on the water-tightness-promoting effect was reduced by adding biochemicals, and the water-tightness-promoting effect was increased at about 1% by weight of biochemicals. In addition, the surfactant was found to have the greatest water-tightness enhancing effect at 0.3% by weight. As mentioned above, 40% by weight of sodium silicate, 1% by weight of biochemicals, and 0.3% by weight of surfactants were most effective in improving the watertightness, and the structure of the concrete was densified by applying the performance improving agent of the present invention to the concrete surface. It was found that there is a significant effect in blocking foreign substances that adversely affect concrete such as chloride ions, sulfate ions, acid rain, and water.

6 shows the results of rebar potential difference experiments.

As shown in the drawing, a 10 mm diameter reinforced bar was embedded in 175 × 175 × 450 mm footed concrete at a depth of 20 mm from the concrete surface to produce reinforced concrete specimens, and standard curing was performed for 5 days. In addition, the reinforced concrete specimens were immersed in a 10% aqueous NaCl solution for 10 days to corrode the reinforcing bars embedded in the concrete. Then, the performance improving agent of the present invention was applied to the concrete surface to periodically measure the rebar potential difference. Rebar potential difference was measured according to the method of measuring the natural potential difference of ASTM C 876, and a reference electrode was used a saturated copper-copper sulfate half cell. From day 1 to day 10, the rebar potential difference is about -200mV and there is a 90% chance that the rebar is not corroded. In addition, the reinforced concrete specimens deposited in a 10% aqueous solution of NaCl for 10 days exceeded -350mV, which is a probability range of 99%, at -550mV, regardless of the concrete cover, but the performance improving agent of the present invention was applied to the reinforced concrete surface. As a result of application, the potential difference value increased with age, and the potential difference approached the potential difference before precipitation in the chloride aqueous solution at the age of 90 days in which the potential difference was not corroded. In addition, the reinforcing corrosion inhibitory effect was almost similar from 5 wt% or more of triethanolamine, which is a reinforcing corrosion inhibitor. As described above, when the performance improving agent of the present invention was applied to the reinforced concrete surface concerned with reinforcing corrosion, it was found that the effect of suppressing reinforcing corrosion was excellent.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

As described above, according to the present invention, when the surface treatment type performance improving agent is applied to the surface of a concrete structure whose performance is deteriorated by salting and neutralization, and penetrated, the chloride ions in the concrete are fixed and the reinforcing bars in the active state are fixed. In addition to suppressing the corrosion activity of the concrete, it has the effect of improving the performance of the structure by improving the pH of the degraded concrete and strengthening the concrete spheres.

Claims (16)

15% to 70% by weight of sodium silicate as a main raw material, 0.05% to 5.0% by weight of biochemicals as a catalyst, and 25% to 84.05% by weight of distilled water. The method of claim 1, The sodium silicate is a composition for the surface treatment type performance improving agent of reinforced concrete structure consisting of one selected from Na ₂ O · 3 SiO ₂ and Na ₂ O · 4 SiO ₂ . The method of claim 1, The composition for surface treatment type performance improving agent of a reinforced concrete structure, wherein the biochemical material is selected from sodium alginate and casein having 15% by weight or less of oil or fat extracted from milk. The method according to any one of claims 1 to 3, Composition for improving the surface treatment type performance of reinforced concrete structure in which more than 3.0% by weight of surfactant is further mixed to lower the viscosity of the mixture. The method of claim 4, wherein Surface treatment type of reinforced concrete structure wherein the surfactant is selected from C ₅ H ₈ SO ₂ LiF (C ₂ F ₄ ) _3-8 or (C ₂ H ₄ O) _n HF (C ₂ F ₄ ) _3-8 Composition for improving performance. The method according to any one of claims 1 to 3, The composition for the surface treatment performance-improving agent of reinforced concrete structure is further mixed with a corrosion inhibitor of less than 7.0% by weight to the composition. The method of claim 6, Composition for improving the surface treatment type performance of the reinforced concrete structure wherein the reinforcing corrosion inhibitor is triethanolamine. The method according to any one of claims 1 to 3, Composition for improving the surface treatment performance of reinforced concrete structures in which more than 7.0% by weight of alkali performance enhancer is further mixed to maintain the pH 13-14. The method of claim 8, The composition for the surface treatment type performance improving agent of reinforced concrete structure, wherein the alkali performance improving agent is selected from sodium hydroxide or calcium hydroxide. Na ₂ O · 3SiO ₂ or Na ₂ O · 4SiO with a 0.05% ~5.0% by weight of alginic acid is selected to _215% by weight to 70% by weight of sodium silicate selected from sodium caseinate, distilled water 25% by weight% by weight ~84.05 A first step of stirring and maintaining the mixed mixture by heating to 70 to 100 ° C; And A second step of acetic acid dropwisely reacting dropwise at intervals of 1 to 5 hours so that the mixture is evenly mixed; Method for producing a composition for surface treatment type performance improving agent of reinforced concrete structure comprising a. The method of claim 10, Method for producing a surface treatment type performance improving composition of a reinforced concrete structure, characterized in that the heating of the first step is performed for 1 to 2 hours. The method of claim 10 or 11, The dropping reaction of the second step is a method for producing a composition for surface treatment type performance improving agent of reinforced concrete structure, characterized in that for each 5 to 50 drops. The method of claim 10 or 11, The reaction time of the second step is a method for producing a surface treatment performance improving composition of a reinforced concrete structure, characterized in that performed for 1 to 2 days. The method of claim 10 or 11, Method for producing a surface treatment type performance improving composition for a reinforced concrete structure further comprises a third step of uniformly dispersing by mixing equal to or less than 3% by weight fluorine-based surfactant in order to lower the viscosity of the mixture after the second step. The method of claim 10 or 11, After performing the second step, the method of producing a surface treatment performance improving composition for a reinforced concrete structure further comprises a fourth step of adding a triethanolamine of less than 7.0% by weight of the steel corrosion inhibitor. The method of claim 10 or 11, After performing the second step, the rebar further comprises a fifth step of mixing more than 7.0% by weight of an alkali donor consisting of the main component of one of NaOH or Ca (OH) ₂ to maintain the pH 13-14 Method for producing a composition for surface treatment type performance improving agent of concrete structures.