JPH09195445A - Reinforcing method of structure by reinforced fiber sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability by arranging a reinforced fiber sheet in which one of warp and weft is composed of reinforced fiber and the other is composed of thermoplastic resin-containing fiber and the warp and the weft are fixed by thermoplastic resin in the thermoplastic resin containing fiber. SOLUTION: Cleaning and polishing processing or the like of a structure surface 11 is performed, and a primer is applied by a roller brush or the like, and a primer layer 12 is formed. Next, matrix resin or the like as a primer coating layer 13 is applied on this primer layer 12, and a reinforced fiber sheet 14 is stuck on this primer coating layer 13. In this reinforced fiber sheet 14, one of warp 31 and weft 32 is formed of reinforced fiber such as carbon fiber and glass fiber, and the other is woven by thermoplastic resin-containing fiber by impregnating or applying thermoplastic resin into or to glass fiber and aramid fiber or the like. Next, a final coating layer 15 is applied on this reinforced fiber sheet 14, and a protective layer 16 such as urethane resin is layered on the final coating layer 15. Therefore, reinforcement and repair or the like of a structure can be effectively performed with high workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reinforcing and repairing structures such as columns, beams, slabs, walls, chimneys, tunnels, etc., using a reinforcing fiber sheet.

[0002]

2. Description of the Related Art Conventionally, in the construction and repair of structures such as columns, beams, slabs, walls, chimneys, tunnels, etc., a reinforcement part has been used as a reinforcement / repair method for giving these structures sufficient strength. There is a method of attaching an iron plate or the like to the etc. However, since the iron plate is heavy and inflexible and difficult to process, the method of attaching the iron plate has a problem that workability is poor.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a method for reinforcing a structure which has good workability and is effective.

[0004]

According to the present invention, one of the warp yarn and the weft yarn is a reinforcing fiber and the other is a thermoplastic resin-containing fiber, and the warp yarn and the weft yarn are made of the thermoplastic resin-containing fiber. There is provided a method of reinforcing a structure, which comprises providing a reinforcing fiber sheet fixed by a plastic resin on the surface of the structure.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The reinforcing fiber sheet used in the reinforcing method of the present invention comprises one of warp and weft composed of reinforcing fiber and the other of thermoplastic resin-containing fiber, wherein the warp and the weft contain the thermoplastic resin. It is fixed by the thermoplastic resin in the fiber.

As the reinforcing fiber, carbon fiber, glass fiber, ceramic fiber, aramid fiber, silicon carbide fiber or the like can be used, but carbon fiber is preferable because it is lightweight and has corrosion resistance.

The reinforcing fiber is usually 1000 to 1000.
It can be composed of 00 filaments, preferably 1000 to 20000 filaments. These filaments can be twisted normally 0.1 to 20 times / m, preferably 0.1 to 5 times / m to form reinforcing fibers. By thus slightly twisting and using, when the reinforcing fiber and the thermoplastic resin-containing fiber are fixed, the thermoplastic resin-containing fiber is in surface contact with the reinforcing fiber to form a preferable reinforcing fiber sheet. be able to.

The reinforcing fiber improves the impregnation property of the matrix resin in the attaching step described later,
Unlike the thermoplastic resin-containing fiber described in detail later, it is preferable that the fiber does not contain a resin.

The reinforcing fiber has a tensile elastic modulus of usually 150.
~ 1000 GPa, preferably 200-1000 GP
a, the tensile strength is usually 2 to 10 GPa, preferably 3.5.
-10 GPa, the breaking elongation is usually 1 to 10%, preferably 1.5 to 10%.

The thermoplastic resin-containing fiber is not particularly limited as long as it contains a thermoplastic resin, but it may be prepared by impregnating or coating glass fiber, aramid fiber or the like with the thermoplastic resin, or by heating glass fiber, aramid fiber or the like with heat. It is possible to use, for example, fibers in which fibers of a plastic resin are mixed or attached.

As the thermoplastic resin, ethylene-vinyl acetate copolymer, polypropylene or the like can be used.

The thermoplastic resin-containing fiber is usually 10 to
It can be composed of 10,000 filaments, preferably 100-1000 filaments.

In the reinforcing fiber sheet, the weave of the warp and the weft is not particularly limited, but a weave such as a plain weave, a twill weave, and a satin weave can be used. Further, the weft yarn and the warp yarn are usually those which intersect at 90 °, but those which intersect at other than 90 ° can also be used.

The spacing between the reinforcing fibers and the thermoplastic resin-containing fibers is not particularly limited, but the reinforcing fibers are retained, the matrix resin described later is improved in the impregnation property, and the direction of the reinforcing fibers is selectively strengthened. From the viewpoints of the above, the spacing between the reinforcing fibers is preferably 0 to 10 mm, more preferably 0 to 5 mm, and the thermoplastic resin-containing fiber is preferably 10 to 500 m.
Every m, more preferably 10 to 200 mm, is sparse.

The method of fixing the warp and the weft is not particularly limited as long as it is fixed by the thermoplastic resin in the thermoplastic resin-containing fiber, and a usual method such as hot melt adhesion can be used. Further, “fixed” means a state in which at least a part of the thermoplastic resin is melted, adhered to or impregnated into the reinforcing fibers, and then cured, so that the warp and the weft are in contact with or fixed to each other.

The designed thickness of the reinforcing fiber sheet is usually 0.
It is desirable that the thickness is 05 to 5 mm, preferably 0.1 to 0.5 mm.

The sheet size of the reinforcing fiber sheet is not particularly limited and is determined according to the structure to be strengthened, but a sheet having a width of 10 to 100 cm and a length of 1 to 500 m can be used.

The fiber basis weight of the reinforcing fiber sheet is usually 10
0 to 1000 g / m ² , preferably 200 to 1000 g
/ M ² .

The reinforcing method of the present invention can be carried out by providing the reinforcing fiber sheet on the surface of a structure such as a pillar, a beam, a slab, a wall, a chimney or a tunnel. The specific construction method is not particularly limited, but for example, as shown in FIG. 1, after forming the primer layer 12 and the undercoat layer 13 on the surface 11 of the structure such as concrete, the reinforcing fiber sheet 14 is attached, and The construction method etc. which form the top coat layer 15 and the finishing layer 16 on it can be mentioned. Hereinafter, it demonstrates still in detail based on this construction example.

First, the structure surface 11 is cleaned, polished, and
Further, pretreatment of the step, the defective portion 17 and the like is performed by using the base adjusting material. As the cleaning method, a method such as disk sander, sand blasting, high pressure cleaning, a method of removing with a waste cloth, an organic solvent or the like can be used. As the base conditioner, a resin having a compressive strength equal to or higher than concrete strength, such as putty-like epoxy resin or epoxy resin mortar, can be used. In addition, in the pretreatment step, it is preferable to perform R finish of the projected corner and the projected corner together.

After the pretreatment is completed, the sticking position of the reinforcing fiber sheet 14 is marked out.

Next, a step of forming a primer layer 12 by applying a primer to the structure surface 11 with a roller brush or the like is performed. As the primer, one having good adhesion to the structure surface 11 and the undercoat layer 13, for example, a solvent type epoxy resin or a solventless epoxy resin can be used.

It is desired that the primer is dried at 20 ° C. for usually 1 to 20 hours, preferably 1 to 15 hours. The mixed viscosity of the primer is
1 to 2000 cps at 20 ° C., preferably 1
The workability is preferably 0 to 1000 cps. In addition, the use temperature of the primer is usually -10 ° C to 5
It is preferably 0 ° C. The primer coating amount is usually 0.01 to ² kg / m ² , preferably 0.1 to 0.5.
It is preferably kg / m ² .

Next, the undercoat layer 1 is formed on the primer layer 12.
A step of applying a matrix resin or the like as No. 3 is performed.

As the matrix resin, a thermosetting resin, a room temperature curable resin or the like can be used, but a room temperature curable resin is preferable from the viewpoint of workability.

The room temperature curable resin preferably has a curing time at 20 ° C. of preferably 30 minutes to 5 hours, more preferably 30 minutes to 3 hours in view of workability.

The design strength development time of the matrix resin is usually 1 to 20 days, preferably 1 to 7 days at 20 ° C. The viscosity at 20 ° C. is usually 10 to 30,000 cps, preferably 100 to 200.
00 cps is desirable because it has good impregnation property and defoaming property.

In the step of applying the undercoat layer 13, the matrix resin is usually applied in a roller brush, rubber spatula or the like in an amount of 0.01 to ² kg / m ² , preferably 0.1 to 1 kg / m ² .
It can be performed by uniformly applying m ² .

Next, a step of attaching the reinforcing fiber sheet 14 to the undercoat layer 13 is performed. In this step, the reinforcing fiber sheet 14 is attached along the marking position immediately after the application of the undercoat layer 13, preferably the surface of the sheet 14 in the direction of the reinforcing fibers, more preferably the center portion to the end portion of the sheet 14. Further, it can be carried out by squeezing with a rubber spatula or the like along the direction of the reinforcing fiber, impregnating the matrix resin into the reinforcing fiber, and expelling the air in the reinforcing fiber to finish the surface smooth.

In the pasting step, if the length of the sheet is too long, the work is difficult. Therefore, the reinforcing fiber sheet 14 can be cut into a proper length and spliced and stuck together. In this case, in order to secure the strength, it is preferable that the jointed portions are attached so as to overlap each other by 100 mm or more in the longitudinal direction (reinforcing fiber direction). The transverse joining is not necessary from the viewpoint of ensuring strength.

Next, a step of applying a matrix resin or the like as the overcoat layer 15 is performed on the reinforcing fiber sheet 14. In this step, the same matrix resin as that used in the undercoating step is used, and it is usually 0.01 to ² kg / m ² , preferably 0.1 to 1 k with a roller brush, rubber spatula, or the like.
It can be carried out by uniformly coating with a coating amount of g / m ² .

In each of the above steps, it is preferable to immediately correct any swelling, wrinkling, or twisting of the fibers. In addition, it is preferable to sufficiently protect from adhesion of dirt and rainfall.

Finally, a finishing process is performed. This step can be performed by applying a weather resistant coating such as urethane resin or fluororesin on the overcoat layer 15 to form the protective layer 16.

In the construction examples described above, only one layer of reinforcing fiber sheet is provided, but in the reinforcing method of the present invention, two or more layers of reinforcing fiber sheet can be provided.
The reinforcing fiber sheet having two or more layers can be provided by repeating the undercoating step, the step of attaching the reinforcing fiber sheet, and the overcoating step as many times as necessary.

[0035]

Since the reinforcing method of the present invention is a reinforcing method in which a reinforcing fiber sheet having a specific structure is provided on the surface of a structure, reinforcement of structures such as columns, beams, slabs, walls, chimneys, tunnels, etc. It is possible to effectively perform repairs with high workability.

[0036]

EXAMPLES The reinforcing method of the present invention will be described in detail below with reference to FIG. 2, but the present invention is not limited thereto.

In FIG. 2, reference numeral 20 denotes a high bridge subjected to the reinforcing method of the present invention. The viaduct 20 is a structure having a pavement portion 21, an RC floor slab 22 made of reinforced concrete, and a bridge pier 23, and the lower surface of the floor slab 22 is reinforced by a layer provided with a reinforcing sheet 14.

For this reinforcement, first, the concrete surface on the lower surface of the floor slab 22 was treated with a disk sander to remove stains on the concrete surface.

Next, the unevenness of the surface due to the step of the formwork or the loss of concrete was applied or filled with a putty-like epoxy resin having a strength equal to or higher than that of concrete, and the surface was finished to be smooth.

After the putty-like epoxy resin was cured, the reinforced fiber sheet bonding position was marked out.

Next, on the concrete surface where the reinforcing fiber sheet is bonded, a viscosity of 600 c at 20 ° C. is obtained with a roller brush or the like.
The ps primer was uniformly applied at a coating amount of 0.3 kg / m ² .

Next, a pot life of 20 minutes at 20 ° C. and a viscosity of 6000 c at 20 ° C. were set at the position of adhesion of the reinforcing fiber sheet.
0.6 kg of ps epoxy resin applied with a roller brush
/ M ² and applied uniformly to undercoat.

As the reinforcing fiber sheet, a unidirectional reinforcing sheet (tensile strength: 3.5 GPa, tensile elastic modulus: 230 GP)
a, thickness 0.11 mm). As shown in FIG. 3, this reinforcing fiber sheet is made by bundling 12000 carbon fiber filaments and lightly twisting 5 times / m, and arranging the weft threads 32 densely with no gaps. A thermoplastic resin-containing fiber containing and as filaments is used as the warp 31 to have a length of 1.5 cm.
Weaving 32 and warp 3
1 and 1 are bonded together by hot melt.

Immediately after applying the epoxy resin, the dimensioned reinforcing fiber sheet is attached to the application surface while aligning the weft yarns in the main bar direction P and aligning with the marking position, and the sheet surface is moved in the reinforcing fiber direction with a rubber spatula. Ironing, epoxy resin was impregnated into the fiber, and the air in the fiber was expelled to smooth it.

After sticking, the epoxy resin was further applied uniformly on the reinforcing fiber sheet at a coating amount of 0.3 kg / m ² , and the reinforcing fibers were sufficiently impregnated to carry out a top coat treatment.

Further, on this, the steps of undercoating, sticking and topcoating are carried out in the same manner, and the reinforcing fiber sheet of another layer is distributed in the direction of force distribution (the orientation direction of the reinforcing fiber of the already stuck reinforcing fiber sheet). It is provided in the direction of going straight). Further, the steps of undercoating, pasting, and topcoating are repeated twice in the same manner, and another reinforcing fiber sheet is provided in the main muscle direction P and subsequently in the distribution muscle direction, and finally the reinforcing fiber sheet is reinforced. Four layers, two layers each being staggered, were provided in the main muscle direction P and the force distribution muscle direction of the part. When swelling, wrinkling, twisting, etc. of the fibers occurred after each top coating step, a rubber spatula, a defoaming roller or the like was used to remove the air inside and to perform a treatment such as ironing in the direction of the reinforcing fibers.

After providing four layers of reinforcing fiber sheet, urethane type weather resistant paint was applied as a finish.

By reinforcing the bottom surface of the floor slab with the reinforcing fiber sheet in this manner, the tensile stress of this concrete is 75 kgf / cm ² to 6 in both the main reinforcement direction P and the distribution reinforcement direction.
The tensile stress of the tensile reinforcing bar is set to 1700 at 8 kgf / cm ^2.
was reduced to 1360kgf / cm ² from kgf / cm ^2,
It was possible to make the stress levels below the allowable stress levels.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a working example of the reinforcing method of the present invention in which a single layer of reinforcing fiber sheet is provided.

FIG. 2 is a cross-sectional view showing an example of reinforcement of an RC floor slab by the reinforcement method of the present invention.

FIG. 3 is a schematic view showing a reinforcing fiber sheet used in the present invention.

[Explanation of symbols]

 12: Primer layer 13: Undercoat layer 14: Reinforcing fiber sheet 15: Topcoat layer 16: Protective layer 22: Floor slab 31: Warp 32: Weft

Claims (1)

[Claims] 1. A reinforcing fiber sheet in which one of the warp and the weft is made of a reinforcing fiber and the other is made of a thermoplastic resin-containing fiber, and the warp and the weft are fixed by a thermoplastic resin in the thermoplastic resin-containing fiber. A method of reinforcing a structure, characterized in that the surface of the structure is provided with.