KR100397138B1 - Repair material and method for repair, restoration and thin overlay traffic topping of concrete structures or bridge decks, and method for thin overlay traffic topping of concrete structures or bridge decks - Google Patents

Abstract

Sectional expansion method of the concrete structure according to the invention is characterized in that the keyway (key-way) is formed by digging a groove of about 50 mm in width, 25 mm in depth, which is a high pressure of 300kg / ㎠ minimum pressure A lower limb cleaning step to remove latent latencies, foreign substances, etc. using a washing machine; Wetting step; 6.6 parts by weight of a concentrated powder comprising a potent cement, a fine-filled mineral mixture, a water vaporization inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrink inhibitor, glass fiber, and a polymer fiber ; 40 parts by weight of silica sand; 40 parts by weight of cement; And 19 parts by weight of water; applying a new and old adhesive primer comprising; On the surface of the base coated with the old and new adhesive primers, it includes a potent cement, a fine-filled mineral mixture, a water evaporation inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrinkage inhibitor, a glass fiber, and a polymer fiber. 16 parts by weight of concentrated powder; 120 parts by weight of silica sand; 80 parts by weight of cement; Plastering and repairing the cross-sectional extension material comprising; 29 parts by weight of water; And a curing step.

Description

Repair material and method for repair, restoration and thin overlay traffic topping of concrete structures or bridge decks, and method for thin overlay traffic topping of concrete structures or bridge decks}

The present invention after the construction of the concrete structure by the various natural strengths and artificial effects, chemically and physically deteriorated due to deterioration phenomena or repairing the site where the concrete surface worn new and old adhesive primer for concrete structures for cross-sectional expansion And repairing and section extension method of concrete structures and section extension method of concrete structures using repair and section extension materials.

Conventional concrete structure repair material was the biggest problem that the adhesive strength with the existing matrix, low tensile strength and weak impact resistance. In addition, there is a problem that the waterproofness, salt resistance, chemical resistance and durability are weak from the fact that there are inherent pores with the components of the cement binder. When acrylic mortar or epoxy mortar is used as the repairing material, there is a lack of air permeability. Therefore, after repairing and reinforcing the cross section of the concrete structure, the repairing part may be dropped due to internal moisture evaporation.

Acrylic mortar is a mixture of portant cement, back cement, polymer cement, silica sand (or Indian sand) and aqueous acryl, and is used in the field by mixing aqueous acrylic with mortar powder which is a mixture of port cement, back cement, polymer cement and silica sand. Done. The mixing ratio (weight ratio) of mortar powder and aqueous acryl is 100: 16-28.

Epoxy mortar is mortar with cement and silica sand added to epoxy.

Normally, the functional ball (plastic plasterer, waterproof ball) is poured into the mortar powder and kneaded with good plastering property. Therefore, when the mortar powder and the aqueous acrylic are mixed and used in the field, the mixing ratio is complicated and the mixing operation is complicated, so the mixing ratio is inconsistent, and the difference in the mixing ratio is increased according to the temperature rise. do. In addition, acrylic mortar has a large waterproofing effect after curing, but there is no air permeability. Therefore, when plastering the entire surface, the moisture absorbed inside the mother body does not pass through the acrylic mortar plastering layer when the air temperature rises, and gathers in the plastering layer. When the air temperature falls, the water turns to water, and when the air temperature drops below zero, the water freezes and expands, causing rapid cracking, peeling-off, rebar exposure, rust generation, freezing-thawing, and deterioration. .

From the above, the following conclusions can be drawn.

(1) The concrete matrix repeats the absorption and dehydration of water. In this case, the life expectancy is secured. However, when the absorbed water cannot be discharged, the life of the concrete is reduced.

(2) In workability, the majority of design and supervisors are only good with material test reports (test reports under optimal conditions). Bad After judgment, they are reflected in the design and supervised, but this is not the right way. The test report is based on the design, considering the working conditions (environment, temperature, weather, construction location, etc.), and the durability is secured depending on how simple it is to use the material of the skilled worker.

It is an object of the present invention to provide a method for repairing and sectional extension of a concrete structure and a method for sectional extension of a concrete structure using a new and old adhesive primer for concrete structures and repair and sectional extension materials.

1 is a view for explaining a repair method of a concrete structure having a defect of scour, peeling peeling, material separation according to the prior art

2 is a view for explaining a repair method of a concrete structure having a defect of rebar exposure according to the prior art;

Figure 3 is a view for explaining a repair method of a concrete structure with a scour, peeling peeling, material separation according to an embodiment of the present invention

4 is a view for explaining a repair method of a concrete structure having a defect of rebar exposure according to another embodiment of the present invention;

5 and 6 are views for explaining a cross-sectional expansion method of a concrete structure forming a key-way according to another embodiment of the present invention;

※ Explanation of symbols for main parts of drawing

10: concrete structure 15: rebar

20: water-based acrylic polymer cement mortar 30: repair and section extension

40: Keyway

Repair and section expansion method of the concrete structure according to the present invention using a high pressure washer of the minimum pressure 300 kg / cm ² The lower ground cleaning step to remove the latent, foreign matters, etc .; Wetting step; 6.6 parts by weight of a concentrated powder comprising a potent cement, a fine-filled mineral mixture, a water vaporization inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrink inhibitor, glass fiber, and a polymer fiber ; 40 parts by weight of silica sand; 40 parts by weight of cement; And 19 parts by weight of water; applying a new and old adhesive primer comprising; On the surface of the base coated with the old and new adhesive primers, it includes a potent cement, a fine-filled mineral mixture, a water evaporation inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrinkage inhibitor, a glass fiber, and a polymer fiber. 16 parts by weight of concentrated powder; 120 parts by weight of silica sand; 80 parts by weight of cement; Plastering and repairing the cross-sectional extension material comprising; 29 parts by weight of water; And a curing step.

Section expansion method of the concrete structure according to the present invention cleaning step; A keyway forming step of making a keyway by digging a groove having a width of about 50 mm and a depth of about 25 mm on the lower surface to prevent peeling off of the repairing and cross-sectional extension material; Wetting step; New adhesive bond primer applying step; Repair and sectioning plastering step; And a curing step.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the term 'repair' is used as a concept that includes both a 'repair of a small range' and a 'restoration of a large range'.

The new adhesive primer, repair and restoration and thin overlay traffic topping material for concrete structures of the present invention include concentrated powder, silica sand, cement, and water.

The concentrated powder is preferably contained 4 to 12% by weight of the fort cement, it contains micro silica (micro silica). The surfactant includes a high performance deflocculent type additive and a humectant, the content of which is preferably 5% by weight or less based on the concentrated powder. The work flexible additive is a mixture of an organic component and an inorganic component, it is preferable that the content of the inorganic component is more. The rheological additive is a mixture of clay and organic components, it is preferable that the content of clay is higher. The improved dry polymer is similar in function to liquid latex and is used for improving cement properties. The amount used is similar to that used in general polymer cement. The glass fiber is preferably contained in about 19% by weight based on the concentrated powder.

The repair and cross-sectional extension material of the present invention has excellent tensile strength as compared to the conventional repair material because it contains glass fibers and polymer fibers, preventing the occurrence of cracks and improve the durability of the structure.

The concentrated powder may further include a corrosion inhibitor, which is preferably organic.

6.6 parts by weight of the concentrated powder, 40 parts by weight of silica sand, and 40 parts by weight of cement are pre-mixed and packaged to commercialize, so that only 19 parts by weight of water can be added to this product (mortar powder for old and new adhesive primers) at the construction site for immediate use. do. In other words, as described above, the skilled worker can be easily constructed according to the habit (excellent workability).

The repair and cross-section extension material for concrete structures of the present invention is pre-mixed, packaged, and commercialized as described above to 16 parts by weight of the concentrated powder, 120 parts by weight of silica sand, and 80 parts by weight of cement as described above. Only 29 parts by weight of water is added to the mortar powder so that it can be used immediately. That is, workability is excellent like the primer.

The repair and cross-sectional extension method of the concrete structure according to the present invention includes a cleaning step, a lower wetting step, applying the new adhesive primer, the repair and the section extender plastering step, and curing step.

The lower part refers to a part to be repaired or expanded in a concrete structure, and in the lower part cleaning step, chipping of contaminants, grease, dust, latencies, weathered areas, etc. deposited on the lower part is performed. It can be removed with high pressure water by chipping, sand blasting or using a high pressure washer with a minimum pressure of 300 kg / cm ² .

The lower wetting step is to make the concrete matrix 10 in a wet state, but no moisture on the surface, this state is called SSD (Saturated Surface Dry) state.

As the old and new adhesive primer, it is preferable to use a mixture of 19 liters of water in the mortar powder for the old and new adhesive primer including 6.6 parts by weight of the concentrated powder, 40 parts by weight of silica sand, and 40 parts by weight of cement. This makes the adhesion between the underlying surface and the repair and cross section extension material to be plastered later by the slurry work. Remove the water droplets in the lower limbs soaked with water and apply the thin and old adhesive primer lightly.

It is preferable to use a mixture of 29 liters of water in the mortar powder for the water-retaining and cross-sectional extension material including 16 parts by weight of the concentrated powder, 120 parts by weight of silica sand, and 80 parts by weight of cement as the water-retaining and cross-section extension material. Plastering of the repair and sectional expansion materials is to be carried out with a certain thickness, it is preferable that the thickness is less than 38 mm. Use a wood or magnesium trowel to spread evenly.

In the curing stage, it is desirable to wet cure for at least 72 hours, and surface cracks occur when the surface moisture evaporates rapidly. Therefore, it is preferable to use a surface moisture evaporation retardant or finish it with water and cover it with polyethylene film. .

After curing, maintenance is unnecessary.

If there is a moving crack in the lower extremity, after the wetting step, a metal net is added to the moving crack and then the new adhesive primer is applied. As the metal mesh, a galvanized welded wire fabric is preferable. In the case of hair line cracks, there is no need to add metal mesh.

When the rebar is exposed to the lower limbs, the rust of the reinforcing bar is removed and cement-based anti-rust agents are applied to the rebar.

The repair and section extension material and the repair and section extension method of the present invention can be applied to a vertical plane or a ceiling as well as a horizontal plane. When applied to the horizontal surface of the mortar powder cement for the repair and sectional expansion material is used for ordinary port cement, but when it is applied to the vertical surface or ceiling, fast cement is used.

The cross-sectional extension method of the concrete structure according to the present invention includes a step cleaning step, a keyway forming step, a bottom wetting step, a new and old adhesive primer application step, repair and section extension material plastering step, and curing step.

The cross-sectional expansion method is mainly used for bridge decks of concrete structures.

The key-way (40) forming step refers to a step of digging a groove having a width of 50 mm and a depth of 25 mm in the base 10 as shown in Figs. By forming the keyway 40 in this way it is possible to prevent the cross-sectional extension portion 30 from being peeled from the existing structure (10).

The other steps are the same as the above-mentioned repair and section extension method of the concrete structure.

Hereinafter, preferred examples and comparative examples of the present invention will be described.

The above examples are intended to illustrate the present invention, but the scope of the present invention is not limited thereto.

Example 1 (Repairing method of concrete structure with scour, peeling peeling, material separation)

Chipping from the cross section of the concrete structure 10 to a rigid portion (dashed line in FIG. 3). In this case, secure the plastering thickness by chipping more than 10 mm after cutting the hand grinder. In other words, durability is improved by chipping and repairing until a healthy mother body comes out. Using a high pressure water washer, dirt and deteriorated areas due to chipping are thoroughly cleaned with a water pressure of 200 kgf / cm 2.

Gemcrete (trade name, manufactured by Gehmite, Canada) is used as the concentrated powder. The mortar powder for old and new adhesive primers mixed with 6.6 kg of gemcrete, 40 kg of silica sand, and 40 kg of normal or fast cement was applied to the surface of the lower limb 10 using a new and old adhesive primer as a mortar powder for the old and new adhesive primer. A new adhesive primer was applied by mixing 29 liters of water into mortar powder for repair and sectional expansion material mixed with 16 kg of gemcrete, 120 kg of silica sand, and 80 kg of normal or solid cement. 20 mm thick on the surface of the base 10. Only one plastering can be applied to the ceiling and walls to a thickness of 20 mm or more. Magnesium or wooden trowels should be used for plastering.

The physical properties of the repair and the cross-sectional extension material 30 is shown in Table 1 below.

In this way, the repair cost was 165,348 won / m 2 (thickness = 20 mm).

Example 2 (Repairing method of concrete structure with defects of rebar exposure)

Chipping from the cross section of the concrete structure 10 to the hard part (dashed line in FIG. 4) and removing rust of the reinforcing bar 15. In this case, secure the plastering thickness by chipping more than 10 mm after cutting the hand grinder. As a result, durability is enhanced. Wash using a high pressure water washer at a pressure of 200 kgf / cm 2. Reinforce the reinforcing bar 15 fiber primer, a cement-based reinforcing corrosion inhibitor, with a brush. After applying the old and new adhesive primer and repair and plastering section extender 30 is carried out in the same manner as in Example 1.

In this way, the repair cost was 185,420 won / m 2 (thickness = 20 mm).

Comparative Example 1 (Repair of Concrete Structures with Scour, Peel-Off, and Material Separation)

As shown in FIG. 1, the cross section of the concrete structure 10 is chipped, and then washed with a high pressure water washer at 200 kgf / cm 2. Amorphous silica (Densie C: trade name) is applied. Aqueous epoxy (HE-256) is applied on top of the reforming system to enhance the adhesion of old and new materials. This is difficult to install wet surface and has the disadvantage of preventing the breathability of concrete. The aqueous acrylic polymer cement mortar 20 is applied thereon to 1.5 mm or less, and then firstly plastered to 10 mm or less. After the first plastering, the 2nd, 3rd and 4th plastering will be repeated in 10 mm increments.

Physical properties of the aqueous acrylic polymer cement mortar 20 was shown in Table 1 below.

In this way, the repair cost was 327,364 won / m 2 (thickness = 20 mm).

Comparative Example 2 (Repair method of concrete structure with defect of rebar exposure)

As shown in FIG. 2, the cross section of the concrete structure 10 is chipped and the rust of the reinforcing bar 15 is removed. Wash using a high pressure water washer at a pressure of 200 kgf / cm 2. Rebar rust preventives (Denshi-P: US trade name) are applied, and then aqueous epoxy (HE-256: ReformSystem product) is applied to strengthen the adhesion of old and new materials. The subsequent procedure is the same as in Comparative Example 1.

In this way, the repair cost was 460,470 won / m 2 (thickness = 20 mm).

It can be seen from the above examples and comparative examples that the repair method of the present invention is simple in construction and low in construction cost per m 2.

Table 1

Properties Repair and section extension materials (Examples 1 and 2) Water-based acrylic polymer cement mortar (Comparative Examples 1 and 2) Compressive strength (kgf / ㎠) 436-490 487 Bending strength (kgf / ㎠) 145-167 208 Tensile strength (kgf / ㎠) 52 to 61 28.9 Adhesion Strength (kgf / ㎠) 20 to 35 28.5 Slope Shear Strength (kgf / ㎠) 168 · Chlorine Ion Permeability 516 Coulombs pass toxicity none none Wear resistance 11.3 0.5 pH 12 or more 12 Modulus of elasticity (psi) 2.0 to 2.9 × 10 ⁶ 1.87 × 10 ⁶ Thermal expansion coefficient (/ ℃) 10 × 10 ⁶ 8 to 13 × 10 ⁶ Impact Strength (in-lb / in ² ) 31.5 to 45 · Absorption rate (%) 2 0.2 to 1 importance 2.2 (wet state) 2.3 (dry state) Breathability (%) 71 · Freeze thawing No loss after 300 cycles ·

Among the required properties of repair or single-sided extension, the first priority is adhesion strength and breathability. As shown in Table 1, the repair and cross-section of the present invention is much better than that of the aqueous acrylic polymer cement mortar.

Using the repair and cross-sectional extension material, the repair and cross-sectional extension method, and the cross-sectional extension method of the present invention can be a thin section repair, such as surface repair, repair and reinforcement of concrete structures. In more detail, the repair and cross-sectional expansion material of the present invention can be used in various buildings, bridges, parking lot floors, water treatment plants, swimming pools, tunnels, dams, etc. as inorganic concrete, and are widely used in epoxy, acrylic, polyurethane, and rubber. It can replace organic concrete such as asphalt and improved latex mortar.

In addition, the cross-sectional extension method using the keyway of the concrete structure in the present invention can prevent the cross-sectional extension portion from being peeled from the existing concrete structure.

Claims (7)

delete delete A step of cleaning the lower limbs, foreign matters and the like by using a high pressure cleaner having a minimum pressure of 300 kg / cm ² ; Wetting step; 6.6 parts by weight of a concentrated powder comprising a potent cement, a fine-filled mineral mixture, a water vaporization inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrink inhibitor, glass fiber, and a polymer fiber ; 40 parts by weight of silica sand; 40 parts by weight of cement; And 19 parts by weight of water; applying a new and old adhesive primer comprising; On the surface of the base coated with the old and new adhesive primers, it includes a potent cement, a fine-filled mineral mixture, a water evaporation inhibitor, a surfactant, a work flexibility additive, a rheological additive, an improved dry polymer, a dry shrinkage inhibitor, a glass fiber, and a polymer fiber. 16 parts by weight of concentrated powder; 120 parts by weight of silica sand; 80 parts by weight of cement; Plastering and repairing the cross-sectional extension material comprising; 29 parts by weight of water; And Curing step; Repair and section expansion method of the concrete structure comprising a. The method of claim 3, further comprising adding a metal net to the moving crack after the lowering wet step, when the lower part includes a moving crack. The repair and cross section of the concrete structure according to claim 3, further comprising applying a fiber prime which is a cement-based anti-corrosive agent to the exposed reinforcing bars when the reinforcing bars are exposed when the reinforcing bars are exposed. Expansion method. Cleaning step; A keyway forming step of forming a keyway by digging a groove having a width of about 50 mm and a depth of about 25 mm on the lower surface to prevent the cross-section extension material from peeling off; Wetting step; New adhesive bond primer applying step; Plastering step of the section expansion material; And Curing step; Section expansion method of concrete structure comprising a. The method of claim 6, wherein the new adhesive primer is used for the cement cement, finely packed mineral mixture, water evaporation inhibitor, surfactant, work flexible additive, rheological additive, improved dry polymer, dry shrink inhibitor, glass fiber, and polymer fiber 6.6 parts by weight of concentrated powder comprising; 40 parts by weight of silica sand; 40 parts by weight of cement; And 19 parts by weight of water; The repair and cross-sectional extension material is concentrated powder comprising a cement cement, a fine-filled mineral mixture, a water evaporation inhibitor, a surfactant, a work flexible additive, a rheological additive, an improved dry polymer, a dry shrinkage inhibitor, a glass fiber, and a polymer fiber 16 Parts by weight; 120 parts by weight of silica sand; 80 parts by weight of cement; And 29 parts by weight of water; Cross section expansion method of a concrete structure comprising a.