JPH0978850A - Fiber reinforced concrete structure and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the compressive strength, by continuously erecting a plurality of layers of long fiber reinforced resin material on the external periphery of a concrete structure and connecting adjacent long materials with a flexible material and making the long materials move separately. SOLUTION: Long materials 1 made of an epoxy resin or the like reinforced with carbon fiber or the like are continuously erected at least by two layers on the external periphery of a structure, when constructing a concrete structure 5 like a column. And adjacent long materials are connected by a flexible material arranged between them. Or the fiber reinforced resin is arranged to form a ring at the outer periphery of the structure 5 so as not to connect the long material 1. Respective long materials 1 are put in the state that they are not substantially bonded so as to be movable as respectively separated structures. In this way, the concrete structure 5 is prevented from deforming due to compressive stresses and permanently kept from the buckling breakage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber reinforced concrete structure in which the outer periphery of a concrete structure is reinforced with a fiber reinforced resin tubular body, and a construction method thereof.

[0002]

2. Description of the Related Art A filled concrete structure in which a steel pipe is filled with concrete is known as one form of a cylindrical or polygonal columnar concrete structure such as a pillar or a pile. In this structure, the steel pipe and concrete are in an adhered state and they behave together. Therefore, when a compressive force in the axial direction is applied to the concrete, the same compressive force is also applied to the steel pipe, resulting in distortion of the steel pipe. Therefore, when the compressive force applied becomes large, the steel pipe partially yields or buckles, and there is a problem that it cannot serve as a reinforcing layer.

Attempts have been made to dispose a reinforcing layer made of fiber reinforced resin instead of the steel pipe. However, when the concrete portion and the reinforcing layer behave integrally, the concrete is destroyed as in the case of the steel pipe. The problem of being directly connected to the destruction of the reinforced resin layer still exists, which has been a major obstacle to the spread of fiber reinforced concrete structures.

[0004]

Therefore, in recent years, when the steel pipe or the composite material reinforcing layer and the concrete are not substantially adhered to each other and they are structurally made to act as separate bodies, the concrete strain or Attempts have been made to prevent the failure from progressing to the failure of the reinforcing layer and to effectively and stably maintain the reinforcing layer. Most of these attempts are difficult in terms of workability and cost such as a method of inserting a non-adhesive film between the reinforcing layer and the concrete layer, or are fragile as the matrix resin of the reinforced resin layer. This is a method with doubt in terms of effect and performance, such as using a resin, and it has been desired to provide a structure that is simple and has a high reinforcing effect.

[0005]

The first gist of the present invention is as follows.
A fiber reinforced concrete structure in which the outer periphery of a concrete structure is reinforced with a fiber reinforced resin tubular body, wherein the fiber reinforced resin tubular body is a fiber reinforced resin layer containing reinforcing fibers that are substantially continuous in the circumferential direction. Inside, there is a plurality of fiber-reinforced resin elongated bodies arranged along the circumferential direction of the fiber-reinforced resin tubular body in a state where the longitudinal directions match, and the layers are substantially adhered. The second gist is a fiber-reinforced concrete structure characterized by not having
Including a reinforcing fiber substantially continuous in the circumferential direction, on the inner wall surface of the tubular fiber-reinforced resin, after arranging a plurality of fiber-reinforced resin elongated body along the circumferential direction in a state where the longitudinal directions of the two are the same, This is a method of constructing a fiber-reinforced concrete structure in which concrete is placed inside.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A fiber-reinforced resin tubular body for reinforcing a fiber-reinforced concrete structure of the present invention comprises a fiber-reinforced resin layer (A) containing reinforcing fibers which are substantially continuous in the circumferential direction and an inner side thereof. , A layer (B) in which a plurality of long fiber-reinforced resin bodies are arranged along the circumferential direction in a state in which the longitudinal direction matches the fiber-reinforced resin tubular body, and the layers are not substantially adhered to each other. is necessary. This makes it possible to obtain a concrete structure having excellent compressive strength, and to easily carry it into a construction site and orient the fibers in the longitudinal direction of the tubular body at the site. The length of the fiber-reinforced resin tubular body is preferably substantially the same as that of the concrete structure.

Next, the layers (A) and (B) will be described in order. In the present invention, the layer (A) is a fiber-reinforced resin containing reinforcing fibers substantially continuous in the circumferential direction outside the layer in which the long fiber-reinforced resin body is arranged along the longitudinal direction of the fiber-reinforced resin tubular body. It is necessary that the layers include at least one layer. This layer (A) can prevent the concrete structure from being deformed or buckled due to compressive stress in the longitudinal direction (axial direction). The thickness of this layer (A) may be determined based on the required strength, but it is preferable that the thickness is two or more from the viewpoint of effective reinforcement.

The layer (A) may include a reinforcing fiber layer which is substantially continuous in the circumferential direction, and the method of forming the layer is not particularly limited. For example, the reinforcing fiber is impregnated with a resin at the site,
A method of winding and curing on a mold, a method of winding and hardening a tow-shaped, tape-shaped or sheet-shaped prepreg pre-impregnated with a resin on a mold, winding a tow or sheet of reinforcing fibers and impregnating with a resin, Any method such as a curing method can be used. It is also possible to form a pipe-shaped molded product for the circumferential reinforcing layer in advance, and dispose the reinforcing layer made of the long fiber-reinforced resin body therein, and then form the concrete portion.

Examples of the reinforcing fibers constituting the layer (A) include inorganic reinforcing fibers such as carbon fibers, glass fibers, boron fibers and alumina fibers, and organic reinforcing fibers such as aramid fibers and polyethylene fibers, but are not limited thereto. Not a thing. As the reinforcing fiber, a single reinforcing fiber may be used, or a plurality of reinforcing fibers may be used in combination. Carbon fiber is preferable because of its high specific strength and high specific elastic modulus.

The resin which constitutes the layer (A) together with the above-mentioned reinforcing fibers includes thermosetting resins such as epoxy resin, unsaturated polyester resin, vinyl ester resin, phenol resin, silicone resin, polyimide resin and maleimide resin. Examples include, but are not limited to, thermoplastic resins such as acrylic resins, polyamide resins, and polyester resins, and photocurable resins that initiate curing upon irradiation with ultraviolet rays or visible light.

Further, the content of the reinforcing fiber in the layer (A) is not particularly limited as long as it is within the range in which the fiber-reinforced resin can be constituted.

The layer (B) constituting the fiber-reinforced resin tubular body for reinforcing the fiber-reinforced concrete structure of the present invention is as follows:
Will be explained.

The layer (B) needs to be a layer in which a long fiber-reinforced resin body is arranged along the circumferential direction in a state where the longitudinal directions of the fiber-reinforced resin tubular body are aligned.

In the present invention, the cross-sectional shape of the long fiber-reinforced resin body may be any of rectangle, circle (including hollow), ellipse and polygon, and a plurality of circles such as a twisted wire are formed. It may be one.

The method for molding the long fiber-reinforced resin body is not particularly limited as long as it can obtain the above-mentioned shape, and examples thereof include pultrusion molding, sheet wrapping, hand layup and spray up. Pultrusion molding and sheet wrap are preferable because the long fiber-reinforced resin has high strength and a uniform shape is easily obtained.

Examples of the reinforcing fibers constituting the long fiber-reinforced resin body include inorganic reinforcing fibers such as carbon fibers, glass fibers, boron fibers and alumina fibers, and organic reinforcing fibers such as aramid fibers and polyethylene fibers. It is not limited. As the reinforcing fiber, a single reinforcing fiber may be used, or a plurality of reinforcing fibers may be used in combination. Carbon fiber is preferable because of its high specific strength and high specific elastic modulus.

The reinforcing fibers in the fiber-reinforced resin elongated body are preferably oriented in the longitudinal direction of the elongated body. As the resin constituting the fiber reinforced resin, epoxy resin, unsaturated polyester resin, vinyl ester resin, phenol resin, silicone resin, polyimide resin, thermosetting resin such as maleimide resin, acrylic resin, polyamide resin, polyester resin, etc. Examples of the resin include a thermoplastic resin and a photocurable resin that starts to cure upon irradiation with ultraviolet rays or visible light, but is not limited thereto.

The content of the reinforcing fibers in the long fiber-reinforced resin body is not particularly limited as long as it is within the range in which the fiber-reinforced resin can be constituted.

For forming the layer of the fiber-reinforced resin elongated body forming the layer (A), the fiber-reinforced resin elongated bodies are arranged in the width direction, and the adjacent fiber-reinforced resin elongated bodies are flexible. It is preferable that they are connected with a conductive material in terms of carrying in and arranging on site. Here, in order to connect the flexible material and the long fiber-reinforced resin body using the flexible material, for example, the following (1) to (3) can be obtained.

(1) A long fiber-reinforced resin body is entangled and woven with fibers. (2) A non-woven fabric in which a long fiber-reinforced resin long body is arranged on at least one surface of the long fiber-reinforced resin long body arranged with an adhesive, and the long fiber-reinforced resin long body is arranged.
Adhere the film or sheet. (3) A nonwoven fabric, a film or a sheet is laminated on at least one surface of an array of elongated fiber reinforced resin and heated to fuse the elongated fiber reinforced resin with the nonwoven fabric, film or sheet.

Fiber of (1), or (2), (3)
Examples of the fibers constituting the non-woven fabric include organic fibers such as polyamide fibers, polyester fibers and aramid fibers, and inorganic fibers such as glass fibers and carbon fibers, which can be selected and used according to the application, but are not particularly limited.

As the adhesive used in the method (2), known adhesives can be used, and although not particularly limited, a sheet adhesive containing a nonwoven fabric as a carrier is preferably used.

The fiber-reinforced resin elongated body and the flexible material may be connected to each other over the entire length in the longitudinal direction of the elongated body.
A form in which a certain pitch is determined and the pitches are connected may be adopted.

In consideration of the strength of the fiber reinforced concrete structure and the like, when there are two or more layers in which the long fiber reinforced resin body is arranged in the circumferential direction of the fiber reinforced resin in the layer (B), It is preferable that a fiber-reinforced resin elongated body is provided in a layer adjacent to the gap portion of the fiber-reinforced elongated body.

Next, a method of constructing the fiber reinforced concrete structure of the present invention will be described. In the construction method of the present invention, a tubular fiber-reinforced resin containing pre-cured substantially circumferentially continuous reinforcing fibers is prepared, and the inner wall thereof has a plurality of fiber-reinforced resin elongated bodies whose longitudinal directions are both. It is most important to arrange them along the circumferential direction so that they are aligned.
With this configuration, it is possible to prevent the concrete structure from being deformed or buckled by the compressive stress in the longitudinal direction (axial direction).

When arranging the long fiber-reinforced resin body in the circumferential direction so that the longitudinal directions of both are aligned, the long space between the long fiber-reinforced resin body and the fiber-reinforced tubular body is fixed by a method that can be removed after concrete is poured. It is preferable from the standpoint of ease of construction that the work is performed, or that the shear strength is fixed with an adhesive or the like that is much weaker than that of the matrix resin forming the fiber-reinforced resin tubular body and the fiber-reinforced resin long body. In particular, the long fiber-reinforced resin members are lined up in the width direction as described above, and it is easy to construct and use the reinforcing material by connecting the long fiber-reinforced resin members adjacent to each other with a flexible material. And a fiber-reinforced resin tubular body layer containing reinforcing fibers in which concrete is continuous in the circumferential direction, and a plurality of fiber-reinforced resins, which are advantageous in terms of carrying-in This is convenient because it is possible to prevent the long body from reaching a layer in which the two are arranged so that their longitudinal directions are aligned with each other and to bond the layers.

[0027]

The fiber-reinforced concrete structure of the present invention comprises a fiber-reinforced resin layer containing reinforcing fibers substantially continuous in the circumferential direction, which is the outermost layer, and a fiber-reinforced resin elongated body, which is inside the fiber-reinforced resin layer. Since the layers with the layers arranged along the circumferential direction so as to match the longitudinal direction of the tubular body are not substantially adhered, the concrete and the fiber-reinforced resin long body are aligned along the longitudinal direction of the fiber-reinforced resin tubular body. And the fiber-reinforced resin layer containing reinforcing fibers that are substantially continuous in the circumferential direction behave as separate structures. Therefore, deformation of the former part and generation of partial defects do not directly affect the latter part, and the latter part is
In particular, it is possible to effectively suppress deformation such as swelling of concrete. As a result, the compressive strength in the longitudinal direction is further enhanced, and this characteristic can be retained permanently.

[0028]

The fiber reinforced concrete structure of the present invention will be described in more detail below with reference to the drawings.

FIG. 1 is a conceptual view of a fiber-reinforced resin elongated body (rectangular cross section) which can be preferably used in the fiber-reinforced concrete structure of the present invention, which is connected by a nonwoven fabric.
FIG. 2 is a conceptual diagram showing a cross section of the fiber-reinforced concrete structure of the present invention.

In the fiber-reinforced concrete structure shown in FIG. 2, the fiber-reinforced resin elongated body 1 is fiber-reinforced inside the fiber-reinforced resin layer (layer (A)) 4 containing reinforcing fibers which are substantially continuous in the circumferential direction. It is composed of a layer (layer (B)) 3 and concrete 5 which are arranged in double (not shown) along the longitudinal direction of the resin tubular body. The layers (A) 4 and (B) 3 are not substantially bonded.

This fiber reinforced concrete structure was constructed through the following steps. (Preparation of Layer (A)) First, a tow prepreg obtained by impregnating carbon fiber TR30 having a modulus of elasticity of 24 ton / mm ² manufactured by Mitsubishi Rayon Co., Ltd. with an epoxy resin was wound around a decomposable cylindrical frame until the thickness became 3 mm. , After heat curing,
The mold was disassembled and removed to obtain Layer (A) 4.

Width of 50 mm × thickness of 1 m formed by drawing the above-mentioned tow prepreg separately for (manufacture of layer (B))
The fiber-reinforced resin elongated body 1 of m was adhered to a polyester film via an epoxy adhesive to obtain the fiber-reinforced resin elongated body shown in FIG. 1 connected with a polyester film. Inside the layer (A), the fiber-reinforced resin long body 1 was doubly arranged so that the longitudinal direction of the elongated body 1 and the longitudinal direction of the layer (A) coincided with each other to form a layer (B).

(Concrete Casting) Concrete 5 was cast inside the layer (B).

[0034]

According to the fiber-reinforced concrete structure of the present invention, a portion composed of a layer in which concrete and a fiber-reinforced resin elongated body are arranged along the circumferential direction in a state where the longitudinal directions of the fiber-reinforced resin tubular body coincide with each other. And the fiber-reinforced resin layer containing reinforcing fibers that are substantially continuous in the circumferential direction behave as separate structures, so that the deformation of the former part and the formation of partial defects may directly affect the latter part. However, the latter part can effectively suppress the deformation such that the former part (particularly concrete) swells, which makes the compression strength in the longitudinal direction higher and maintains this property permanently. It will be possible. Furthermore, according to the construction method of the present invention, it is possible to easily construct the above-mentioned fiber-reinforced concrete structure on site.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a long fiber-reinforced resin body (rectangular cross section) that can be preferably used in the fiber-reinforced concrete structure of the present invention, which is connected by a polyester film.

FIG. 2 is a conceptual diagram showing a cross section of the fiber-reinforced concrete structure of the present invention.

[Explanation of symbols]

1 Fiber Reinforced Resin Long Body 2 Polyester Film 3 Layer in which Fiber Reinforced Resin Long Body is Arranged (Layer (B)) 4 Fiber Reinforced Resin Layer (Layer (A)) Containing Reinforcement Fibers that are Substantially Circumferentially Continued 5 concrete

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Claims (5)

[Claims] 1. A fiber reinforced concrete structure in which the outer periphery of a concrete structure is reinforced with a fiber reinforced resin tubular body, and the fiber reinforced resin tubular body contains reinforcing fibers substantially continuous in the circumferential direction. A fiber-reinforced resin layer and a layer inside the fiber-reinforced resin long body, which is arranged along the circumferential direction of the fiber-reinforced resin tubular body in a state where the longitudinal directions coincide with each other, and the layers are substantially Fiber-reinforced concrete structure characterized in that it is not physically bonded. 2. A layer in which a long fiber-reinforced resin body is arranged along the longitudinal direction of a fiber-reinforced resin tubular body has a plurality of long fiber-reinforced resin bodies arranged in the width direction, and adjacent fiber-reinforced resin. The fiber-reinforced concrete structure according to claim 1, wherein the fiber-reinforced concrete structure is a layer in which long members are connected by a flexible material. 3. There are two or more layers in which a long fiber-reinforced resin body is arranged along a longitudinal direction of a fiber-reinforced resin tubular body, and a fiber-reinforced resin is provided in a gap portion of the fiber-reinforced long body in an adjacent layer. The fiber-reinforced concrete structure according to claim 2 or 3, which has a long body. 4. A plurality of elongated fiber-reinforced resin bodies are provided along the circumferential direction on the inner wall surface of a tubular fiber-reinforced resin containing reinforcing fibers that are substantially continuous in the circumferential direction, with the longitudinal directions of the two being aligned. The method of constructing a fiber-reinforced concrete structure, in which concrete is placed inside the building after placing it. 5. When arranging the fiber-reinforced resin elongated body,
The reinforcing material formed by connecting adjacent fiber-reinforced resin elongated bodies of a plurality of fiber-reinforced resin elongated bodies arranged in the width direction with a flexible material is arranged so that both longitudinal directions are aligned. Construction method of fiber reinforced concrete structure.