JP2000204769A - Reinforcing method for concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a reinforcement effect which is excellent in adhesiveness while being lightweight and durable because of its structure made of a fiber sheet by a method wherein a reinforcing fiber sheet is bonded to the surface of concrete and a steel plate is fixed, facing the concrete surface, with hardening resin injected into a gap and hardened. SOLUTION: Honeycombs and laitance over the surface 1 of concrete to be reinforced are removed and washing and drying are applied to the surface. A primer 2 is applied to the washed surface 1, and the primer is hardened with adjustment made to unevenness. Then, a reinforcing carbon fiber sheet 3 is stuck to the surface of the primer 2. A steel plate 4 is positioned, facing the concrete, and the steel plate 4 is fixed to the concrete with bolts 5 with a distance being provided. The periphery of the steel plate 4 is sealed up with epoxy putty 8, and a liquid epoxy resin 9 is injected with a pump 61 through an injection port 6. With the epoxy resin 9 hardened, the concrete 1 and the steel plate 4 are stuck and united together through the reinforcing fiber sheet 3. Since reinforcement effect is developed by the reinforcing fiber sheet 3, lightness in the weight and durability can be improved with the thickness of the steel plate 4 being reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reinforcing method for reinforcing concrete as a structure.

[0002]

2. Description of the Related Art Conventionally, as a reinforcing method for preventing cracking and destruction of concrete caused by an earthquake or other external force, a method using fiber as a reinforcing material and a method using steel plate as a reinforcing material have been independently adopted. I have. Fiber reinforcement is a concrete layer that requires reinforcement, a single layer or multiple layers of a fiber sheet made of woven or non-woven fabric such as carbon fiber, aramid fiber, or glass fiber. This is a method of permeating, curing and bonding.

[0003] The above-mentioned conventional method has the advantage that the fiber sheet and the curable resin as the reinforcing material are light in weight, have a secure adhesiveness, and exhibit an excellent reinforcing effect. However, there is a disadvantage in that the process of attaching this to concrete is complicated, and the fiber sheet is expensive in terms of cost and man-hours.

[0004] The steel plate is reinforced by fixing a steel plate with an anchor bolt with a gap of 4 to 9 mm between the concrete requiring reinforcement and the steel plate, sealing the periphery with a sealing material, and then hardening the gap. Adhesion is performed by injecting and curing a conductive resin.

[0005] According to this method, the reinforcing effect is closely related to the thickness of the steel sheet, and the reinforcing effect increases as the thickness of the steel sheet increases. However, when the weight of the steel plate is large, the load applied to the concrete increases accordingly, which is a weak point in terms of durability. In addition, an air filter may be generated between the concrete and the curable resin. There is a problem that the reinforcing effect is low in the portion where the air filter is generated, and it is difficult to confirm that there is no air filter.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, reduces the weight of a steel plate, increases the durability of concrete, and enhances the adhesion between concrete and a steel plate to stabilize the reinforcing effect. It is an object of the present invention to provide a concrete reinforcing method that can be ensured in a concrete manner.

[0007]

According to the reinforcing method for concrete of the present invention, a reinforcing fiber sheet is adhered to a concrete surface, a steel sheet is fixed to the concrete facing the reinforcing fiber sheet, and the concrete and the steel sheet are interposed. After the curable resin is injected and filled into the gaps formed, the curable resin is cured to bond and integrate the steel plate, the curable resin, and the concrete.

The reinforcing fibers used in the present invention are typically carbon fibers, aramid fibers, glass fibers and the like.
In the case of carbon fiber, the basis weight is preferably 200 to 600 g / m ^{2 and} the thickness as a fiber sheet is 0.1 to 0.4 mm.
And the tensile strength is preferably 35500 kgf / cm ² or more. In the case of aramid fiber, the basis weight is 200 ~
600 g / m ² is preferable, the thickness as a fiber sheet is 0.1 to 0.4 mm, and the tensile strength is 21000 kgf / c.
It is preferably at least m ² .

The steel sheet used has a yield point strength of 300 N /
mm ² or more, tensile strength of conventional with 390 N / mm ² or more, the thickness of the steel sheet as compared with conventional thickness, can be used those than about 9mm of.

[0010] As the curable resin used for bonding,
Epoxy resins, unsaturated polyester resins and the like can be mentioned.

(Function) The curable resin injected into the gap between the concrete and the steel sheet is impregnated into the fiber sheet adhered to the concrete, and penetrates to the concrete surface to fill the gap. After the resin is filled, it does not flow and is securely bonded to concrete, and
The hardening resin and the steel plate are securely bonded together, and the concrete and the steel plate are integrated. Since the reinforcing effect of the fiber sheet is exerted, the thickness of the steel plate can be reduced, and the reinforcing structure is lightweight, has improved durability, and can be reduced in cost.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional view showing an embodiment of the present invention. In FIG. 1, the concrete to be reinforced (30 cm
(× 30 cm × thickness 6 cm) 1 The junkers and latencies on the surface were removed with a razor tool, and dirt and adhered oil were washed with a detergent and dried. An epoxy-based primer 2 was applied to the washed surface and cured, and an epoxy-based putty (not shown) was applied to a portion of the surface of the primer 2 where the unevenness was large to correct unevenness.

A reinforcing fiber sheet 3 made of carbon fiber (having a basis weight of 300 g / m ² , a thickness of 0.1 mm, and a tensile strength of 35500 kgf / cm ² ) is coated with a primer 2 by a defoaming roll.
Pasted on the surface. Bolt hole 41 of steel plate 4 having a thickness of 9 mm
The steel plate 4 was fixed to the concrete 1 by inserting the anchor bolt 5 into the fixing hole 11 of the concrete 1 with a gap of 4 mm facing the concrete 1.

Next, an inlet 6 was attached between one end of the steel plate 4 and the concrete 1, an outlet 7 was attached to the other end of the steel plate 4, and the periphery of the steel plate 4 was sealed with an epoxy putty 8. Liquid epoxy resin 9 is pumped from injection port 6 to pump 6
The exhaust port 7 was closed when the injected resin 9 flowed out from the exhaust port 7 and the injection was completed.

Thereafter, the epoxy resin was cured for 24 hours, and the tensile strength of the steel sheet was measured by a tensile tester.
The adhesive strength was 25 kg / cm ² .

Comparative Example 1 A steel sheet was adhered to concrete in the same manner as in Example 1 except that no reinforcing fiber sheet was used, and the adhesive strength was measured to be 19 kg / cm.
^{Was 2} .

[0017]

According to the concrete reinforcing method of the present invention, the hardening resin is bonded to the concrete via the reinforcing fiber sheet, and the hardening resin is also bonded to the steel sheet, so that the concrete and the steel sheet are surely integrated. Therefore, the reinforcing effect can be stably secured. In addition, since the reinforcing effect of the reinforcing fiber sheet is exhibited, the thickness of the steel plate can be reduced, and the reinforcing structure is lightweight, has improved durability, and can be reduced in cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1: Concrete 2: Epoxy primer 3: Reinforcement fiber sheet 4: Steel plate 5: Bolt 6: Injection port 7: Exhaust port 8: Epoxy putty 9: Liquid epoxy resin 11: Fixing hole 41: Bolt hole 61: Pump

Claims (1)

[Claims] 1. A reinforcing fiber sheet is bonded to a concrete surface, a steel sheet is fixed to concrete facing the reinforcing fiber sheet, and a curable resin is injected and filled into a gap formed between the concrete and the steel sheet. Thereafter, a concrete reinforcing method is characterized in that the curable resin is cured so that the steel sheet, the curable resin and concrete are bonded and integrated.