JP2924599B2 - FRP reinforced concrete structure and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FRP reinforced concrete structure in which a concrete structure such as an elevated road pier, a chimney, a building column, or a wall is reinforced with fiber reinforced plastic (FRP), and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, in order to cope with an increase in load on a bridge pier of an elevated road due to widening of a road or the like, a reinforcing method of attaching a steel plate or an FRP plate to a concrete structure using an adhesive has been used. . However, when a steel plate is used, there are problems that a heavy machine is required for attaching the steel plate because the steel plate itself is heavy, and that the weight of the steel plate itself is also applied to the concrete structure. Further, there are also problems such as that if there is unevenness on the attaching surface, it cannot be attached as it is, or the adhesion state between the concrete and the steel plate cannot be confirmed, resulting in poor adhesion.

[0003] In addition, although it is not necessary to use a heavy machine when attaching the FRP plate, it is not possible to attach the FRP plate as it is when there is unevenness on the attaching surface, as in the case of the steel plate. However, there is a problem that the bonding state may not be confirmed, so that the bonding may be defective.

Therefore, as one of the reinforcing methods for solving these problems, there is known a method in which a reinforcing fiber material is attached and cured at room temperature while impregnating a matrix resin of a room temperature curing type. In a columnar concrete structure, a reinforcing fiber material generally has a component in which fibers are arranged in a longitudinal direction and a component in which fibers are arranged in a circumferential direction, and these materials are alternately used for bending reinforcement and shear reinforcement, respectively. Is laminated and impregnated with a resin, and attached to a structure. In the molding operation, since the usable time of the resin is limited, it is important how the lamination is performed while regulating the arrangement direction of the fibers in a short time.

However, in the method in which the reinforcing fiber material is brought into contact with the concrete structure as it is and impregnated with the resin, the reinforcing fiber material is not fixed to the concrete structure. However, there is a problem that it is difficult to fix the fixing member at a predetermined position, and a desired reinforcing effect may not be obtained.

To solve this problem, Japanese Utility Model Laid-Open No. 4-845 has been proposed.
No. 57 describes a method of constructing while fixing an end portion of a reinforcing fiber material using a fixing device. However, in this method, when the FRP has a laminated structure,
There is a problem that the fixing jig cannot be mounted on the uncured FRP or that the fixing jig needs to be mounted or removed for each operation, resulting in poor work efficiency.

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, and makes it possible to easily attach a reinforcing fiber material to a predetermined position in an operation of attaching the reinforcing fiber material. It is an object of the present invention to provide a method for producing an FRP reinforced concrete structure capable of reliably obtaining an effect, and an FRP reinforced concrete structure obtained by the method.

[0008]

According to the present invention, there is provided a method of manufacturing an FRP reinforced concrete structure, comprising the steps of: attaching a fixing material for fixing a reinforcing fiber material to a concrete structure; Along with the reinforcing fiber material extending along the surface of the structure, the reinforcing fiber material is fixed to the fixing material with a stopper, and the fixed reinforcing fiber material is impregnated with a room temperature curing type matrix resin, and the fixing material is removed. The method comprises curing the resin without removing it.

Further, in the method for reinforcing a concrete structure according to the present invention, a fixing material for fixing a reinforcing fiber material is attached to a concrete structure, and the reinforcing fiber material is provided over the fixing material and the surface of the concrete structure. And fix the reinforcing fiber material to the fixing material with a stopper, impregnate the fixed reinforcing fiber material with a room temperature curing type matrix resin, and remove the fixing material.
Instead of curing the resin .

Further, in the method for repairing a concrete structure according to the present invention, a fixing material for fixing a reinforcing fiber material is attached to a concrete structure, and the reinforcing fiber material is provided over the fixing material and the surface of the concrete structure. And fix the reinforcing fiber material to the fixing material with a stopper, impregnate the fixed reinforcing fiber material with a room temperature curing type matrix resin, and remove the fixing material.
Instead of curing the resin .

Further, in the FRP reinforced concrete structure according to the present invention, a fixing material is attached to the concrete structure, and FRP is stuck on the fixing material and on the surface of the concrete structure. The FRP
Only through the anchoring material and into the concrete structure.
It is characterized in that it is fixed to the fixing material by a stopper that does not reach the structure .

[0012]

In the method of the present invention, a fixing material is attached to a concrete structure, and a reinforcing fiber material is attached to the fixing material by a fastener. The reinforcing fiber material is fixed at the target position and along the fixing material and the concrete structure surface. In this state, the matrix resin is impregnated, but since the reinforcing fiber material is fixed, it does not slip off during the resin impregnation operation. In addition, the FRP of the laminated configuration
In this case, the target layer can be surely formed for each layer by repeating the above method. Therefore, the fiber orientation can be reliably regulated in a desired direction, and an excellent reinforcing effect can be easily obtained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the FRP reinforced concrete structure of the present invention and a method of manufacturing the same will be described below in detail with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view showing an example of an FRP reinforced concrete structure obtained by the method for producing an FRP reinforced concrete structure of the present invention. In the figure, the FRP reinforced concrete structure 1 is configured as a column concrete structure. At the connection between the concrete structure 2 and the ceiling 3, that is, at the top of the concrete structure 2, a fixing material 4 is attached to the column with an adhesive, and the fixing material 4 and the column concrete structure are further attached. The FRP 5 is attached so as to cover the entire object 2. A stop 6 is provided at the overlapping portion of the fixing material 4 and the FRP 5, and the stop 6 penetrates through the FRP 5, and its tip is pierced into the fixing material.

This FRP reinforced concrete structure 1
It can be produced as follows. First, the concrete surface to which the reinforcing fiber material is to be attached is sanded with a sander.

Next, after removing the abrasive powder from the sanding surface, the sanding surface is degreased using an organic solvent, and a primer is applied to the sanding surface.

After the primer has hardened, the fixing-like member 4 is attached to the top of the column of the concrete structure 2, that is, the connecting portion between the ceiling 3 and the column 2 using an adhesive.

The fixing position of the fixing material 4 is such that when a bending external force is applied to the column structure fixed to the floor surface, the bending stress generated near the floor surface is the largest, and the generated stress becomes smaller toward the upper part. In view of the fact that the reinforcing fiber material is suspended and the resin impregnation work, it is usually preferable to attach the reinforcing fiber material to the uppermost portion of the FRP attachment portion in the structure. Regarding the mounting position in the circumferential direction,
Usually, it is installed over the entire circumference in the circumferential direction of the column concrete structure, but it may be partial.

The material of the fixing material is a material such as wood, plastic, rubber, etc., into which a stopper described below can be driven, and this is attached to the concrete surface with an adhesive such as a room temperature curing type epoxy resin.

The cross-sectional shape of the fixing material may be any shape such as a triangle, a quadrangle, a polygon, and a circle. However, in the case of a rectangular cross section, a step may be formed between the fixing material and the concrete surface, and the reinforcing fiber material may peel off from the concrete surface during the attaching operation of the reinforcing fiber material. A shape having a taper at the boundary between the surfaces is preferable. If there is a dent on the concrete surface, embed the fixing material in this part so that there is no step with the concrete surface. It is more preferable because the construction becomes less defective.

Next, the end portion of the reinforcing fiber material is fixed to the fixing material 4 by a stopper 6 as shown in FIG. The stopper may be a U-shaped wire such as a staple or a stapler, a U-shaped nail, or the like, preferably a linear one that can be fixed. The size of the stopper and the mounting interval are usually such that the wire diameter D is 0.1 to 5 mm and the pressing width W is 10 mm.
A fixture having a size of １００100 mm is attached such that the distance between the centers of the stoppers is 10 to 100 mm. However, if the fabric weight is large or the fabric is easily misaligned, the impregnated resin will cause a part of the fabric to fall off due to the weight of the reinforcing fiber material and the resin. It is preferable to reduce the interval and increase the number of stoppers.

The driving length L of the stopper is 5 to 50.
It may be appropriately selected within the range of mm depending on the size of the fixing material and the number of reinforcing fiber materials used. However, if the length is too short, the length penetrating the fixing material is short, and the fixing material is detached when attached. On the other hand, if it is too long, it penetrates the fixing material to reach the concrete surface, and the pressing of the reinforcing fiber material is insufficient, which is not preferable.

If the driving position is too far from the concrete surface, a gap may be formed between the reinforcing fiber material and the concrete surface in a state of being hung by the stopper before the resin is hardened, which may result in poor construction. It is better to be as close as possible. Here, if the fixing material has a taper, the fixing material may be driven into a portion as close to the concrete surface as possible.

The driving angle of the stopper does not necessarily have to be perpendicular to the tapered surface of the fixing material. When the tip of the stopper hits the concrete surface, the driving angle of the stopper is shifted so as not to hit the concrete surface. Do it.

Further, when an external force is generated in the columnar structure fixed to the floor surface as described above, the bending stress generated near the floor surface is the largest, and the generated stress becomes smaller toward the upper part. Even if the upper portion, that is, the portion to which the fixing material is attached, is not impregnated with the resin, the reinforcing effect is not greatly reduced.

Since the fixing material portion protrudes from the concrete surface, if the reinforcing fiber material is to be wound in the circumferential direction in the column, the circumferential length difference between the fixing material attaching portion and the fixing material non-attaching portion is increased. Can not be wound well. In such a case, a cut may be made in the reinforcing fiber material at the corner, and the circumferential length difference may be adjusted at the cut.

Examples of the reinforcing fiber material include sheet-like materials made of reinforcing fibers such as carbon fiber, glass fiber, and aramid fiber. Here, when an external force such as bending acts on the concrete structure, the concrete has a small tensile breaking strain and easily cracks. Therefore, the tensile strength is 200 kgf / mm ² or more, and the tensile modulus is 15,000 k.
A high-strength, high-elasticity reinforcing fiber having a characteristic of gf / mm ² or more is preferable. More preferably, since the concrete is alkaline, excellent in alkali resistance properties, and,
Tensile strength of 350 kgf / mm ² or more, tensile modulus 2
Carbon fibers having a characteristic of 000 kgf / mm ² are preferred.

The form of the reinforcing fibers is preferably a woven fabric from the viewpoint of the reinforcing effect. In particular, the reinforcing fibers can be reinforced only in a predetermined direction, and the fibers are oriented in one direction because the reinforcing fiber material is not wasted. Directional fabrics are more preferred.

Here, from the viewpoint of handling, JP-A-61-3
In the case of a woven fabric described in Japanese Patent No. 4244, and a woven fabric in which the yarn intersections of the entire woven fabric are subjected to a filling treatment, it is needless to say that there is no misalignment during handling.
This is more preferable because the fiber orientation can be regulated without misalignment even during resin impregnation.

The basis weight of the reinforcing fiber material is 100 g / m ^2-
A range of 400 g / m ² is suitable. 100 g / m ²
If it is below, the reinforcing effect per sheet is small, so it is necessary to increase the number of layers, and the work of laminating and impregnating the resin becomes complicated. On the other hand, if it is 400 g / m ² or more, the thickness becomes large, so that the resin impregnation work may be insufficient.

Next, the reinforcing fiber material is impregnated with the matrix resin by a roller on site. Then, in the case of the FRP having a laminated structure as shown in FIG. 1, the reinforcing fiber material of the second layer is similarly fixed to the fixing material at the end of the reinforcing fiber material with the stopper, and then impregnated with the matrix resin. . This process is repeated for a predetermined number of reinforcing fiber materials, and then cured at room temperature, whereby a target FRP can be produced.

The fiber arrangement direction of the reinforcing fibers may be any direction. In the columnar concrete structure, the fibers arranged in the longitudinal direction for bending reinforcement and the fibers arranged in the circumferential direction for shear reinforcement are arranged. It is only necessary to alternately laminate the reinforcing fiber materials having the respective components. Here, all the reinforcing fiber materials arranged in the longitudinal direction can be fixed to the fixing material by the stopper, but the reinforcing fiber material arranged in the circumferential direction is fixed to the fixing material by the stopper except for the one located at the top. Cannot fix. For this reason, as a measure to prevent the slip-off, the number of laminations is set to 1 or 2 in a layer having the same fiber arrangement, and the fiber weight per layer (the fiber weight per layer x the number of laminations) is reduced to 500 g / m ² or less. If the reinforcing fiber material is located on both sides of the layer and the layer where the reinforcing fiber material is fixed by the stoppers, slipping-off can be prevented. Here, the fiber basis weight per layer is preferably in 150~500g / m ² for easy fall displacement by its own weight when the resin impregnated exceeds 500 g / m ^2.

Regarding the number of reinforcing fiber materials to be laminated,
It may be determined from the magnitude of the external force acting on the structure, etc. However, if the number of laminations is too large, shearing failure occurs at the portion of the concrete covering between the reinforcing bar and CFRP, so that the fabric weight is usually 200 g / m2. ² is 15 layers or less.

The portion of the reinforcing fiber material overlapping the fixing material may or may not be impregnated with resin. In particular, from the viewpoint of later lamination work, if the resin is impregnated, it may become difficult to drive the stopper, and in such a case, it is preferable not to impregnate the resin.

The matrix resin is a room-temperature-curable resin that can be used on site, and is a thermosetting resin such as an epoxy resin, an unsaturated polyester resin, or a vinyl ester resin. Among them, epoxy resin and vinyl ester resin, which are excellent in alkali resistance because concrete is alkaline, are preferable.

In the present invention, an existing concrete structure can be reinforced. As for the reinforcement of the concrete structure, when the road is widened on the pier of an elevated road, the load acting on the pier naturally increases, so the reinforcement must be performed. For this reason, a concrete structure can be reinforced by a method similar to the above-described manufacturing method.

In repairing a concrete structure, for example, when cracks occur due to long-term use and the load-carrying capacity is reduced, it must be repaired to restore the original load-carrying capacity. Therefore, the concrete structure can be repaired by a method similar to the above-described manufacturing method.

Example 1 A concrete structure 2 having a square cross section of 90 cm on a side and a height of 3 m was reinforced with FRP. First, the entire pillar was sanded using a sander. Next, after removing the abrasive powder on the sanding surface by brushing, the sanding surface was degreased using an organic solvent, and a primer was applied to the sanding surface. At the top of the pillar, that is, at the connecting portion between the ceiling 3 and the pillar 2, as a fixing material, wood 4 having a right-angled triangular cross section and a side length of 3 cm sandwiching a right angle is used. Araldite AV138, Hardner HV99
8 was mixed) around the column. Next, a unidirectional carbon fiber fabric (CO1623L manufactured by Toray Industries, Inc.) having a fabric width of 100 cm is arranged on the wood 4 such that the fibers are arranged (hereinafter referred to as 0 ° lamination) in the longitudinal direction of the pillar. A staple 6 having a wire diameter of 2 mm, a pressing width of 30 mm, and a driving length of 15 mm was fixed to the wood 4 with a stapler at 50 mm intervals at the end of the woven fabric. Here, the carbon fiber fabric is 5
The pieces were wrapped cm by cm, and a cut was made at the corner where the wood overlapped to adjust the circumferential difference. Then, the carbon fiber fabric was impregnated with a room temperature curing type epoxy resin (Shobond FV clear) by a roller. The overlapping portion between the carbon fiber fabric and the wood was not impregnated with the resin.

Next, the woven fabric is arranged so that the fiber arrangement of the woven fabric is in the circumferential direction of the pillar (hereinafter referred to as 90 ° lamination).
A staple 6 having a wire diameter of 2 mm, a pressing width of 30 mm, and a driving length of 15 mm is fixed to the wood 4 at intervals of 50 mm using a stapler at an end of the woven fabric, and a room temperature curing type epoxy resin (show bond) is applied to the carbon fiber woven fabric with a roller. FV clear). Here, as in the case of the 0 ° lamination, the carbon fiber woven fabric was cut at the corner where it overlapped with the wood to adjust the perimeter difference, and was not impregnated with the resin. In addition, the width of the carbon fiber fabric was 100 cm, which was insufficient in the longitudinal direction of the column, so that the ends of the carbon fiber fabrics were overlapped with each other by 5 cm, and the resin impregnation work was performed. Note that the second and subsequent carbon fiber fabrics in the 90 ° layer cannot be fixed by the stoppers, but the 0 °
The layers are secured by fasteners and do not slip off. Since the 90 ° layer sandwiched between the fixed layers is unlikely to slip off, the carbon fiber woven fabric was attached while overlapping the ends.

Next, 0 ° lamination and resin impregnation were performed in the same manner as described above, and a total of three layers were laminated. After that, leave it at room temperature all day and night,
The resin was cured.

Thus, it was confirmed that the carbon fiber woven fabric in which the fibers were arranged in the longitudinal direction of the pillars was fixed to the wood 4 and did not shift down due to its own weight even when impregnated with resin. In addition, it was confirmed that the carbon fiber woven fabric in which the fibers were arranged in the circumferential direction was not displaced by its own weight even when impregnated with resin because the layers on both sides in contact were fixed to the wood.

[0041]

According to the present invention, a concrete structure is fixed to a concrete structure at the time of producing an FRP reinforced concrete structure which is bonded and cured while impregnating a reinforcing fiber material with a room temperature curing type matrix resin on the surface of the concrete structure. After fixing the reinforcing fiber material to this fixing material with a stopper, and attaching the reinforcing fiber material while impregnating the matrix resin into the reinforcing fiber material, the reinforcing fiber material shifts during the resin impregnation work on the reinforcing fiber material. Will not fall. Therefore, the fiber orientation can be regulated in a desired direction, and an excellent reinforcing effect can be expected. Further, since it is not necessary to correct the fiber orientation at the time of resin impregnation, workability is greatly improved.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of an FRP reinforced concrete structure according to one embodiment manufactured by a manufacturing method of the present invention.

FIG. 2 is an enlarged side view of the fixing material of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 FRP reinforced concrete structure 2 Concrete structure 3 Ceiling 4 Fixing material 5 FRP 6 Stopper

Claims (4)

(57) [Claims] 1. A fixing material for fixing a reinforcing fiber material is attached to a concrete structure. The reinforcing fiber material extends along the fixing material and the surface of the concrete structure. Fix to the fixing material, impregnate the fixed reinforcing fiber material with the room temperature curing type matrix resin, and remove the fixing material.
A method for producing an FRP reinforced concrete structure, comprising curing a resin without removing the resin . 2. A fixing material for fixing a reinforcing fiber material is attached to a concrete structure, and the reinforcing fiber material extends along the fixing material and the surface of the concrete structure. Fix to the fixing material, impregnate the fixed reinforcing fiber material with the room temperature curing type matrix resin, and remove the fixing material.
A method for reinforcing a concrete structure, characterized by curing a resin without curing. 3. A fixing material for fixing a reinforcing fiber material is attached to a concrete structure, the reinforcing fiber material is made to extend along the fixing material and the surface of the concrete structure, and the reinforcing fiber material is fixed by a stopper. Fix to the fixing material, impregnate the fixed reinforcing fiber material with the room temperature curing type matrix resin, and remove the fixing material.
A method for repairing a concrete structure, comprising curing a resin without removing the resin . 4. A fixing material is attached to a concrete structure, and an FRP is attached over the fixing material and a surface of the concrete structure, and the FRP is attached to the FRP.
Only through the anchoring material and into the concrete structure.
An FRP reinforced concrete structure fixed to a fixing material by a fastener that does not reach the structure.