KR102004223B1 - Waterproofing and Repair Strengthening Method of Concrete Structures Using Environment-Friendly Aggregate and Reinforcing Materials - Google Patents

Abstract

According to the present invention, by using a blast furnace slag cement with excellent durability and an admixture with excellent acid resistance, chemical resistance, and durability to repair a cross-sectional area damaged by acid or sulfuric acid, it is possible to prevent the loss of strength inside the concrete due to chemical erosion and the occurrence of expansion and cracking by producing ettringite, and thus possible for Co^2 reduction by utilizing industrial by-products and providing an eco-friendly cross-sectional recovery method.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a waterproofing and repairing method of concrete structures using eco-friendly aggregates and reinforcing materials,

The present invention relates to a method for repairing a damaged section of a concrete structure caused by deterioration of a cross section of a bridge and a concrete structure of the building, and a method of repairing a damaged section of the concrete structure by durability By using the excellent blast furnace slag cement and the admixture with excellent acid resistance, chemical resistance and durability, it is possible to prevent the strength loss in the concrete by chemical erosion and to prevent the expansion and crack by generating ettringite, Water and sewage treatment plants, tunnels, drain locks, agricultural irrigation canals, harbor facilities, dams, bridges, and other facilities, while enhancing resistance to sulfates and improving durability by using bottom ash aggregate and pozzolanic admixture, Slab, beam, column, foundation etc. Degraded concrete block Or durable the recovery to repair the surface relates to waterproofing and maintenance reinforcement of concrete structures with superior eco-aggregate and reinforcement.

In general, concrete structures are widely used as construction materials for semi-permanent structures due to their excellent formability and durability. However, when such concrete structures are exposed to the environment for a long period of time, the concrete deteriorates due to chemical erosion, the steel is corroded and the concrete is cracked and peeled due to the volume expansion. As a result, the performance of the concrete structure is deteriorated.

In winter, pop-out breakage of concrete occurs due to freezing and thawing action of concrete, and if exposed to automobile exhaust gas and boiler exhaust gas for a long time, internal reinforcement is corroded due to neutralization and concrete Cracks, peeling, or peeling may occur.

In addition to these causes, deterioration of concrete, deterioration of concrete, alkali aggregate reaction, industrial wastewater and sewage may cause deterioration of concrete and corrosion of reinforcing steel.

In the case of cracks or detachment of concrete due to various reasons, it is necessary to restore it to a circular shape in order to relieve the rebar and to use the structure stably, and various concrete structure circular restoration methods are used in the field.

In the past, to repair the section of concrete that has been lost due to corrosion of reinforcing bars, the damaged concrete was removed and the section of the concrete was filled with the repair mortar. In order to suppress the chemical erosion, the maintenance mortar was mixed with the admixture However, this physical method has a problem that the chemical erosion resistance performance is insufficient, and when minute cracks are generated due to the initial hydration heat of the maintenance mortar, the physical erosion is caused by the chemical reaction.

The patent documents for the repair (repair) of such a concrete structure are as follows.

Patent Document 10-1352903 discloses a mortar composition for repairing and reinforcing a concrete structure comprising 5 to 50% by weight of a binder, 10 to 40% by weight of a filler, and 20 to 70% by weight of an aggregate, 20 to 50% by weight of a cement composition containing 100 parts by weight of a powder, 20 to 50 parts by weight of a slag-containing mixture, and 20 to 40 parts by weight of a phosphorus acid generator or flue gas desulfurizing agent; 30 to 60 wt% portland cement; 5 to 20% by weight of a cellulose fiber; And 5 to 10% by weight of an EVA resin, wherein the slag-containing mixture comprises 65 to 80% by weight of slag with a specific surface area of 6,000 to 7,000 cm2 / g, 10 to 20% by weight of lime, 5 to 15% And 5 to 20% by weight of a kiln dust having an average particle diameter of 1 to 10 탆 and a powdery degree of 8,000 cm 2 / g to 20,000 cm 2 / g, are mixed and pulverized in a vibration mill to obtain a mechanochemical activated mixture However, there is a problem that the long-term strength improvement effect and the initial strength development are insufficient.

Korean Patent Registration No. 10-1352903

The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a waterproof concrete structure using eco-friendly aggregate and reinforcing material which is easy to apply to a concrete structure requiring repair in a section due to deterioration and has improved mechanical properties, durability, And a repair and reinforcement method.

In addition, the present invention improves the chemical resistance by using as a bottom ash aggregate and an admixture which are industrial by-products, and can improve the long-term strength by inducing a pozzolanic reaction by SiO 2 containing 50% or more, The object of the present invention is to provide waterproofing and repairing and reinforcing methods for concrete structures using eco-friendly aggregates and reinforcing materials having chemical resistance using bottom ash and pozzolanic reaction admixtures which allow hydrates to tighten texture and increase water resistance and chemical resistance have.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a waterproofing structure for concrete structures using eco-friendly aggregate and reinforcing material, which is easy to apply to concrete structures requiring repairing of sections by deterioration and improved workability of high strength, durability, And a repair and reinforcement method.

(B) removing rust from the exposed reinforcing bars; (c) treating the surface of the concrete surface; (d) applying a rustproof primer (E) installing a tough stiffener, (f) filling repair mortar, and (g) applying a surface protective agent to repair the section of the damaged concrete structure due to performance degradation In the method,

The rust-preventive primer preferably comprises 43.45 to 44.35 wt% of blast furnace slag cement, 17.95 to 18.75 wt% of yttrium oxide, 12.95 to 13.85 wt% of silica flower powder, 8.85 to 9.85 wt% of zirconia, 5.65 to 6.75 wt% of bottom ash, 4.75 to 5.25 wt% of mica, 2.75 to 3.95 wt% of mica, 0.09 to 0.40 wt% of polycarboxylic acid-based water reducing agent, and 0.01 to 0.20 wt% of fiber reinforcement;

The toughness stiffener may be made of at least one of carbon, glass, or basalt fiber in the form of a mesh, and at least one of two or more of high strength steels made of ㅁ type wire netting;

Wherein the repair mortar comprises 41.20 to 45.40 wt% of mixed silica sand, 37.80 to 40.40 wt% of blast furnace slag cement, 4.50 to 7.00 wt% of bottom ash, 2.20 to 5.50 wt% of silica flower powder, 2.20 to 3.30 wt% of zirconia, Wherein the composition comprises 2.00 to 2.50 wt% of a copolymer, 0.90 to 1.70 wt% of a mica, 0.80 to 1.60 wt% of an anhydrous gypsum, 0.20 to 0.40 wt% of a polycarboxylic acid-based water reducing agent, and 0.10 to 0.30 wt% of a fiber reinforcement.

The surface protection agent is characterized in that the anti-neutralization agent forms a coating layer having a thickness of 150 to 300 mu m.

The present invention has the following effects.

According to the present invention, by using bottom ash, which is an industrial by-product, as a fine aggregate and an admixture, it is possible to improve the chemical resistance and to induce the pozzolanic reaction by SiO 2 contained in 50% or more, It is possible to reduce the unit weight and reduce the amount of natural aggregate to be used, thereby preventing depletion of resources.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a construction procedure of a concrete structure repairing and reinforcing method according to the present invention; FIG.
2 is an evaluation table showing the adhesion of the present invention.
3 is an evaluation table showing the compressive strength of the present invention.
4 is an evaluation table showing the bending strength of the present invention.
FIG. 5 is an enlarged sectional view of the concrete part of the present invention, in which the waterproofing and repairing and reinforcing method is implemented.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Prior to the description, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and should be construed in accordance with the technical aspects of the present invention.

(B) removing the rust of the exposed reinforcing bar (20), (c) a pretreatment step of the surface of the concrete (10), (d) Applying the rustproof primer 30, (e) installing the tough stiffener 40, (f) filling the repair mortar 50, (g) applying the surface protective agent 60, Wherein the rustproof primer (30) is a blast furnace slag cement, yttrium oxide, silica flower powder, zirconia, bottom ash, styrene butadiene, mica, polycarbons And a fiber reinforcing material, wherein the repair mortar (50) comprises a mixture of silica sand, blast furnace slag cement, bottom ash, silica flower powder, zirconia, styrene butadiene, mica, anhydrous gypsum, polycarboxylic acid- Include Provides a method to repair a section of the concrete structure, characterized in that for applying the surface protective agent (60).

The composition and weight of the rust-preventive primer composition 30 according to the present invention will be described in detail.

The rust preventive primer 30 according to the present invention comprises 43.45 to 44.35 wt% of blast furnace slag cement, 17.95 to 18.75 wt% of yttria, 12.95 to 13.85 wt% of silica flower powder, 8.85 to 9.85 wt% of zirconia, 5.65 to 6.75 wt , 4.75 to 5.25 wt% of a styrene-butadiene copolymer, 2.75 to 3.95 wt% of a mica, 0.09 to 0.40 wt% of a polycarboxylic acid-based water reducing agent, and 0.01 to 0.20 wt% of a fiber reinforcing material.

The blast furnace slag cement has a specific gravity of 2.90 to 3.15 g / cm < 3 > and an average particle size of the blast furnace slag is 7 to 15 mu m and a blast furnace slag fine powder having a specific surface area of 6,000 to 8,000 cm < It is preferable to use them in combination to improve the long-term strength and improve the adhesion. When the blast furnace slag cement is used in an amount of less than 43.45 wt%, the effect of alkaline protective coating formation and strength enhancement is insufficient. When the blast furnace slag cement is used in an amount of more than 44.35 wt%, the viscosity increases and flowability is poor.

The yttrium oxide is a crystal of a whitish white equiaxed crystal system or a scandium oxide type structure and has a reducing suppression function. And has a particle size of 10 to 15 mu m, and when it is used in an amount of less than 17.95 wt%, the reduction reaction is insufficient and the anti-corrosive effect is reduced. When using more than 18.75 wt%, there is a problem that the speed of initialization is slowed down.

The silica flower powder is a silica material having 99.5% or more of silica and has excellent filling property to mortar pores and forms a tight structure. When using less than 12.95 wt% of silica powder, there is a possibility of penetration of external deterioration factor due to lack of a closed structure, and 13.85 wt %, There is a possibility of cracking due to the lack of blast furnace slag cement.

The zirconia has a melting point of 2,700 DEG C which is insoluble in water and has a high melting point, so that it has excellent abrasion resistance and corrosion resistance, and is excellent in resistance to abrupt temperature change. When the content is less than 8.85 wt%, the tackiness and strength are insufficient and the corrosion resistance is decreased. When the content is more than 9.85 wt%, the viscosity increases and the workability is decreased.

The bottom ash has an aggregate of 1 mm or less and is excellent in unit weight reduction effect, resistance to seawater water and chemical resistance, and can control the setting time. When using less than 5.65 wt%, chemical resistance may be insufficient, and more than 6.75 wt% Increase in water absorption rate and workability may be deteriorated.

The styrene butadiene has a role of improving the adhesion and improving the adhesion, and when it is used less than 4.95 wt%, there is a problem that the adhesion and adhesion to the existing concrete surface become insufficient. Due to the increase of the viscosity when using more than 5.25 wt% There is a problem that the workability is lowered.

The mica has a specific gravity of 2.45 to 2.65 g / cm3 and has a specific surface area of 3,100 to 4,300 cm2 / g. It fills fine pores and functions as a luster and performs a corresponding role of ultraviolet rays. When using less than 2.75 wt% The fillability and gloss of the composition are decreased, and when the composition is used at 3.95 wt% or more, the viscosity increases and the workability becomes poor.

The polycarboxylic acid-based water reducing agent has the function of improving the workability, securing the fluidity and reducing the unit water, thereby improving the strength and reducing shrinkage. When it is used less than 0.09 wt%, fluidity and workability are lowered, and when it is used more than 0.40 wt%, material separation and rebound ratio are increased and materials used can be increased.

The fibrous reinforcement is used for preventing cracking and improving bending strength, and it is preferable to mix any one or two or more selected from among fibers such as carbon, glass, nylon, PP, hemp, and jute. When it is used less than 0.01 wt%, crack resistance due to external force and drying shrinkage is insufficient, and when bundles of 0.20 wt% or more are used, bundles of fibers are not satisfactory.

The construction of the tough stiffener 40 according to the present invention will be described in detail.

The toughness stiffener 40 according to the present invention may be manufactured by forming at least one of carbon, glass, and basalt fiber into a mesh in the form of a mesh, by using a high strength steel material in the form of a wire netting, To provide a high strength tough reinforcing material for repair and reinforcement which improves the function of the cracking resistance and delamination of the repair mortar in response to the contraction and expansion of the concrete structure.

The composition and weight of the repair mortar (50) composition according to the present invention will be described in detail.

The repair mortar 50 according to the present invention comprises 41.20 to 45.40 wt% of mixed silica sand, 37.80 to 40.40 wt% of blast furnace slag cement, 4.50 to 7.00 wt% of bottom ash, 2.20 to 5.50 wt% of silica flower powder, , 0.20 to 0.40 wt% of a polycarboxylic acid-based water reducing agent, and 0.10 to 0.30 wt% of a stiffened styrene-butadiene copolymer, 0.90 to 1.70 wt% of a natural silicate mineral, 0.80 to 1.60 wt% .

Characterized in that said mixed silica is composed of silica sand having a specific gravity of 2.60 g / cm < 3 > or more and silica sand having a specific gravity of 2.60 to 2.80, And when it is used more than 45.40 wt%, the content of blast furnace slag cement is lowered, so that the compressive strength is decreased and the workability is lowered.

The blast furnace slag cement has a specific gravity of 2.90 to 3.15 g / cm < 3 > and an average particle size of the blast furnace slag is 7 to 15 mu m and a blast furnace slag fine powder having a specific surface area of 6,000 to 8,000 cm < It is preferable to use them in combination to improve the long-term strength and improve the adhesion. When it is used in an amount of less than 37.80 wt%, the effect of alkaline protective film formation and strength enhancement is insufficient, and when it is used more than 40.40 wt%, viscosity increases and flowability is poor.

The bottom ash has an aggregate of 1 mm or less and is excellent in unit weight reduction effect, resistance to seawater water and chemical resistance, and can control the setting time. When using less than 4.50 wt%, chemical resistance may be insufficient. Increase in water absorption rate and workability may be deteriorated.

The silica flower powder is a silica material having a purity of more than 99.5% to form a closed structure with excellent filling property in the mortar pore. When the amount of the silica flower powder is less than 2.20 wt% When using wt% or more, there is a possibility that cracks are generated due to the lack of blast furnace slag cement.

The zirconia has a melting point of 2,700 DEG C which is insoluble in water and has a high melting point, so that it has excellent abrasion resistance and corrosion resistance, and is excellent in resistance to abrupt temperature change. When it is used less than 2.20 wt%, the tackiness, lack of strength and corrosion resistance are lowered, and when it is used more than 3.30 wt%, viscosity increase and workability are lowered.

The styrene-butadiene has a role of improving the adhesion and improving the adhesion, and when it is used at less than 2.00 wt%, the adhesion and adhesion to the existing concrete surface become insufficient, and when the viscosity is higher than 2.50 wt% There is a problem that the workability is lowered.

The mica has a specific gravity of 2.45 g / cm < 3 > or more and has a specific surface area of 3,100 to 4,300 cm < 2 > / g and fills fine pores and acts as a luster. When less than 0.90 wt% there is a problem in that the viscosity is increased and the workability is poor when using more than wt%.

The anhydrous gypsum is a calcium sulfate salt having no crystal number and is a composition produced by heating a crystal gypsum to a high temperature of 500 ° C or higher and is used for controlling the setting time of cement. When it is used less than 0.80 wt%, the hardening time of the maintenance mortar is delayed to some extent and the workability is insufficient.

The polycarboxylic acid-based water reducing agent has the function of improving the workability, securing the fluidity and reducing the unit water, thereby improving the strength and reducing shrinkage. When it is used less than 0.20 wt%, fluidity and workability are lowered. When it is used more than 0.40 wt%, material separation and rebound ratio are increased and materials to be used can be increased.

The fibrous reinforcement is used for preventing cracking and improving bending strength, and it is preferable to mix any one or two or more selected from among fibers such as carbon, glass, nylon, PP, hemp, and jute. When it is used less than 0.10 wt%, it is not enough to cope with cracks due to external force and drying shrinkage.

The antifouling agent as the surface protective agent 60 according to the present invention is characterized in that at least one of chlorinated rubber, epoxy, urethane, fluorine resin and ceramic is applied to the surface of the earthquake-proof reinforcement to prevent performance deterioration and durability do.

As the surface protecting agent 60, an anti-neutralization agent may form a 150 to 300 mu m coating layer to prevent weathering and chemical erosion.

First, the rust-preventive primer was prepared by mixing 43.9 wt% of blast-furnace slag cement, 18.35 wt% of yttrium oxide, 13.4 wt% of silica flower powder, 9.35 wt% of zirconia, 6.2 wt% of bottom ash, 5.1 wt% of styrene-butadiene copolymer, , 0.245 wt% of a polycarboxylic acid-based water reducing agent, and 0.105 wt% of a fiber reinforcing material. The water / binder ratio was 25%.

Second, the maintenance mortar was composed of 43.3 wt% of mixed silica sand, 39.1 wt% of blast furnace slag cement, 5.75 wt% of bottom ash, 3.85 wt% of silica flower powder, 2.75 wt% of zirconia, 2.25 wt% of styrene-butadiene copolymer, wt.%, anhydrous gypsum of 1.2 wt.%, polycarboxylic acid based water reducing agent of 0.3 wt.% and fiber reinforcing material of 0.2 wt.%, and water / binder ratio of 16%. According to one embodiment of the present invention thus prepared, a rust-preventive primer is applied, then a high-stiffness stiffener is installed at the center, and then filled with repair mortar.

[Comparative Example 1]

The mortar of concrete of domestic company A was regarded as Comparative Example 1.

[Comparative Example 2]

The concrete mortar for repairing concrete of domestic company B was used as Comparative Example 2.

[Test Example 1]

≪ Evaluation of adhesion &

In order to evaluate the adhesion performance of the rust-preventive primer and the repair mortar according to the embodiment of the present invention, the adhesive strength was measured in accordance with the polymer cement mortar for repairing the KS F 4042 concrete structure.

As a result of the adhesion test, it was confirmed that adhesion performance was higher than Comparative Examples 1 and 2 of the present invention, as shown in Fig.

[Test Example 2]

≪ Evaluation of compressive strength &

In order to evaluate the compressive strength of the repair mortar according to one embodiment of the present invention, Example 2, Comparative Examples 1 and 2 were prepared according to the polymeric cement mortar for repairing the KS F 4042 concrete structure, and the compressive strength was measured.

As a result of the compressive strength evaluation, the compressive strength of Example 2 according to the present invention was measured to be higher than the compressive strengths of Comparative Examples 1 and 2, and a synergistic effect of 23.4 to 26.2 MPa .

[Test Example 3]

≪ Evaluation of flexural strength &

In order to evaluate the bending strength of the repair mortar according to one embodiment of the present invention, the flexural strength of the concrete mortar of Example 2 and Comparative Examples 1 and 2 was measured in accordance with KS F 4042 polymer concrete mortar for repairing concrete structures.

Bending Strength Evaluation Result As shown in FIG. 4, the bending strength of Example 2 according to the present invention was higher than the bending strengths of Comparative Examples 1 and 2, and a synergistic effect of 8.22 to 8.98 MPa was obtained at 28 days strength compared to Comparative Examples 1 and 2 there was.

10: Concrete
20: Rebar
30: Anti-rust primer
40: High stiffness stiffener
50: Repair mortar
60: Surfactant

Claims (1)

(a) removing the damaged concrete, (b) removing the rust from the exposed reinforcing bar, (c) treating the surface of the concrete, (d) blast-furnace slag cement, yttrium oxide, zirconia, bottom ash, mica, (E) installing a tough stiffener; (f) filling repair mortar comprising blast furnace slag cement, bottom ash, zirconia, mica and water reducing agent; (g) A method for repairing a section of a concrete structure, comprising applying an anti-neutralization agent as a surface protecting agent,
The rust-preventive primer preferably comprises 43.45 to 44.35 wt% of blast-furnace slag cement, 17.95 to 18.75 wt% of yttria, 12.95 to 13.85 wt% of silica flower powder, 8.85 to 9.85 wt% of zirconia, 5.65 to 6.75 wt% of bottom ash, 4.75 to 5.25 wt% of mica, 2.75 to 3.95 wt% of mica, 0.09 to 0.40 wt% of polycarboxylic acid-based water reducing agent, and 0.01 to 0.20 wt% of fiber reinforcement;
The toughness stiffener may be made of at least one of carbon, glass, or basalt fiber in the form of a mesh, and at least one of two or more of high strength steels made of ㅁ type wire netting;
Wherein the repair mortar comprises 41.20 to 45.40 wt% of mixed silica sand, 37.80 to 40.40 wt% of blast furnace slag cement, 4.50 to 7.00 wt% of bottom ash, 2.20 to 5.50 wt% of silica flower powder, 2.20 to 3.30 wt% of zirconia, Wherein the composition comprises 2.00 to 2.50 wt% of a copolymer, 0.90 to 1.70 wt% of a mica, 0.80 to 1.60 wt% of an anhydrous gypsum, 0.20 to 0.40 wt% of a polycarboxylic acid-based water reducing agent, and 0.10 to 0.30 wt% of a fiber reinforcement.
The waterproofing and repairing method of a concrete structure using an environmentally friendly aggregate and a reinforcing material, wherein the neutralizing agent forms a coating layer of 150 to 300 mu m.

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