JP3094851B2 - Civil and architectural reinforcement - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing member for civil engineering and construction, and more particularly to reinforcing a pier, a girder, a floor slab, and the like of a road bridge with fiber reinforced plastic (hereinafter also referred to as FRP), and a column of a reinforced concrete structure. TECHNICAL FIELD The present invention relates to a civil and architectural reinforcing member suitable for use in reinforcing concrete and walls, reinforcing building panels, and the like.

[0002]

2. Description of the Related Art Since FRP has excellent mechanical properties while being lightweight, it has begun to attract attention as a reinforcing member for civil engineering and construction. Above all, carbon fiber reinforced plastics (hereinafter, also referred to as CFRP) using carbon fibers having a large specific elastic modulus and a large specific strength show high mechanical properties.

For example, recently, piers and floor slabs such as road bridges,
The girder is deteriorated due to rust of reinforcing steel, fatigue of reinforcing steel, carbonation of concrete, etc., which is a problem. The reinforcement is
Usually, a steel plate is attached to concrete or a beam with an adhesive, but this operation often needs to be performed in a narrow space surrounded by the beam. However, the steel plate is heavy and requires a hoist such as a crane truck for sticking, which is complicated, and sometimes the hoist cannot be used. Further, the concrete surface is not necessarily smooth but has an uneven surface. Therefore, in order to completely bond the steel plate and the concrete, it is necessary to increase the thickness of the adhesive layer so as to eliminate the influence of the irregularities on the concrete surface, which is very inefficient.

On the other hand, recently, an FRP reinforcing method of reinforcing a pier, a floor slab, a girder, or the like of a road bridge with an FRP plate has been attracting attention because the reinforcing work can be performed without interrupting the traffic of cars. I have. In this method, the resin is applied directly to the concrete surface so that it is sufficiently reinforced even if the concrete surface has some irregularities, and then, for example, the resin is impregnated and cured in a unidirectional sheet-like fiber reinforced material. This is performed by a so-called hand lay-up molding method in which a fiber reinforced plastic plate is molded and, at the same time, an FRP plate is bonded to concrete. Unlike the steel plate reinforcement method, there is no need to transport heavy objects, so work efficiency is good and FRP can be formed on site. Similarly, as for the reinforcement of columns and walls of reinforced concrete buildings, and also the reinforcement of building panels, attention has been paid to the reinforcement method using FRP plates.

[0005] Such an FRP reinforcing member is usually formed by molding a plurality of layers of a reinforcing fiber material impregnated with a resin, and is easy to handle at the time of molding, at the time of molding, and conforms to the mold. A reinforced fiber woven fabric in the form of a woven fabric is frequently used as a reinforcing fiber material from the viewpoints of easiness and excellent properties as an FRP after molding.

[0006] By the way, the higher the fineness of the carbon fiber yarn, the higher the productivity in the precursor and the flame-proofing step and the firing step, and the cheaper the carbon fiber yarn can be manufactured.

However, a normal reinforcing fiber woven fabric is formed by using reinforcing fiber yarns obtained by bundling reinforcing fibers into a substantially circular cross section. Therefore, in a woven state, the warp yarns and the weft yarns intersect. The cross section of the reinforcing fiber yarn is elliptical, and the woven yarn is greatly crimped. In particular, in a reinforcing fiber woven fabric using a thick reinforcing fiber yarn, this tendency is increased because the thick weft yarn and the thick warp yarn are intersected.

For this reason, in a reinforced fiber woven fabric in which the reinforcing fiber yarns are crimped greatly, the fiber density becomes non-uniform and high mechanical properties cannot be sufficiently exhibited. Also, if the reinforcing fiber yarn is crimped greatly, the surface smoothness of the formed FRP is not good. In civil engineering and building structures, good surface smoothness is often required. Furthermore, a reinforced fiber woven fabric using a thick reinforced fiber yarn generally has a large fabric weight and thickness, so that resin impregnating property at the time of forming a prepreg or FRP is deteriorated.

Accordingly, FRP and CFRP obtained by using a reinforcing fiber woven fabric obtained by weaving thick reinforcing fiber yarns have a large number of voids in the resin, so that high mechanical properties cannot be expected.

On the other hand, when the fabric weight is reduced by using a thick reinforcing fiber yarn, a void formed between the reinforcing fiber yarns increases. For this reason, when FRP or CFRP is formed using a reinforcing fiber woven fabric having a small fabric weight, the volume content of the reinforcing fiber decreases, and voids of the resin are intensively generated in voids formed between the reinforcing fiber yarns. However, there is a disadvantage that a high-performance composite material cannot be obtained.

[0011]

SUMMARY OF THE INVENTION The present invention focuses on such a current situation, and particularly, in a reinforcing member for civil and architectural use using FRP, the member is made of FRP using a specific reinforcing fiber fabric.
An object is to obtain a target high reinforcing effect and obtain good surface smoothness by using a member containing RP.

[0012]

According to the object of the present invention, there is provided a reinforcing member for civil and architectural construction according to the present invention, which is formed by thermosetting into a plurality of layers of reinforcing fiber material.
A civil and architectural reinforcing member containing a fiber reinforced plastic impregnated with a conductive resin, wherein at least one layer of the reinforcing fiber material has a single yarn having a yarn width of 3 to 16 mm and a yarn width / thickness ratio of 2
0 or more , the fracture strain energy is 4.0 mm · kgf / m
A reinforcing fiber woven reinforcing fiber yarns of at least one of the warp and weft consisting of m ³ or more flat carbon fiber yarn, flat yarn fibers are parallel in at least one of the woven state of the warp and weft It is made of a woven fabric.

In order to obtain a uniform and high reinforcing effect, FR
The cover factor of the reinforcing fiber woven fabric in P is preferably as high as possible, and preferably has a cover factor of 85% or more. Such a reinforcing fiber woven fabric is impregnated with a resin and adhered to, for example, the surface of an inorganic material to form a reinforcing member for civil engineering and construction.

Further, at least one of the warp yarn and the weft yarn may be formed by laminating a plurality of the flat reinforcing fiber yarns. In this manner, a woven fabric having a large basis weight can be formed, and FRP having a larger fiber volume content can be formed.

As the reinforcing fiber yarn, a carbon fiber yarn is used in the present invention, and a carbon fiber yarn having a high elastic modulus and a high strength is particularly preferable. The flat reinforcing fiber yarn is usually in the form of a multifilament yarn.

It is necessary that the woven yarn of the woven fabric composed of such flat reinforcing fiber yarns has substantially no twist and fibers are arranged in parallel. Here, "substantially no twist" means
A state in which there is no more than one turn of twist per 1 m of yarn length. That is, it is a state in which there is no twist. It is necessary that the fabric is substantially free of twist. for that purpose,
The untwisted flat reinforcing fiber yarn bobbin is intercepted and unwound, and the warp yarn and the weft yarn are supplied so as to prevent untwisting and twisting, thereby forming a woven fabric.

When the woven yarn is twisted, the yarn width is narrowed and bundled at the twisted portion to increase the thickness, and irregularities are generated on the surface of the woven fabric. For this reason, in the woven fabric, when an external force acts, stress concentrates on the twisted portion, and the FRP
When formed into a uniform shape, the mechanical properties become non-uniform.

The flat reinforcing fiber yarn single yarn has a yarn width of 3 to 16 m.
m. The yarn width in this range is easy to weave, and the optimum flat state is easily obtained from the relationship with the yarn thickness. The yarn width / yarn thickness ratio is set to 20 or more. If it is less than 20, it is difficult to minimize the crimp of the woven yarn in order to obtain a high cover factor.

In the reinforcing fiber woven fabric made of such an optimally flat and substantially untwisted woven yarn, the crimp at the intersection of each woven yarn can be suppressed to a very small value even if the fineness of the woven yarn is increased. When FRP or CFRP is used, high strength characteristics can be obtained. Since the crimp is small, FRP or CF
When RP is used, the surface smoothness is good, and a desired surface form of the civil engineering / architecture reinforcing member can be easily obtained. Further, since the fineness of the woven yarn can be increased, the woven yarn, and eventually the reinforced fiber woven fabric, can be manufactured at lower cost.

Further, since the crimp is suppressed to a very small value, the fabric weight can be set high, and the high cover factor can be set as described above while the flat state of the yarn is secured. Therefore, in the FRP, the fiber content can be set high, and the resin-rich portion between the yarns can be extremely small, so that a composite material having high strength and uniform mechanical properties can be obtained.

Furthermore, since each yarn is maintained in a flat state in the form of a woven fabric, the impregnating property of the resin is extremely good. Therefore, a composite material having more uniform properties can be obtained, and the target mechanical properties can be easily obtained.

Here, the cover factor Cf (%) is an element related to the size of the void formed between the yarns, and when a region having an area S ₁ is set on the woven fabric, the area S ₁
When the area of the void formed in the weaving yarn is S ₂ , the value is defined by the following equation. Cover factor Cf = [(S ₁ −S ₂ ) / S ₁ ] × 1
00

The reinforcing fiber woven fabric of the present invention uses a warp or a weft made of thin flat reinforcing fiber yarns. Therefore,
The woven fabric has a small degree of eyesight, that is, a large cover factor. When the FRP is molded using such a reinforced fiber woven fabric having a large cover factor, a uniform molded product can be obtained, and voids do not occur in the resin and fiber distribution unevenness such as concentration of stress does not occur.

As a method for producing the flat yarn as described above, for example, in the production process of the reinforcing fiber yarn,
A fiber bundle composed of a plurality of reinforcing fibers may be spread to a predetermined width by a roll or the like, and may be held in a flat shape or may be held in a sizing agent or the like so as not to return to the original shape. In particular, to maintain the flat shape well,
It is preferable to attach a small amount of a sizing agent of about 0.1 to 1.5% by weight to the flat yarn.

In the case where the flat reinforcing fiber is used as a warp and weft woven fabric, the woven fabric weight is 100 to 300.
g / m ² . Further, in the case of a woven fabric in which flat reinforcing fiber yarns are at least one of a warp yarn and a weft yarn, wherein at least one of the warp yarns and the weft yarns is a woven fabric in which a plurality of flat reinforcing fiber yarns are laminated, a woven fabric weight is used. Is preferably 200 to 600 g / m ² .
Since it is a flat woven yarn, crimping can be suppressed to a small value even when woven in such a state that a plurality of layers are laminated. Then, the fiber density of the woven fabric can be increased by lamination.

Further, it may be in the form of a woven fabric using auxiliary yarns. As the auxiliary yarn, it is preferable to use a flat woven yarn composed of fine fibers having a fineness of 2,000 denier or less, and more preferably 50 to 600 denier. If the fineness of the auxiliary yarn is large, the crimp becomes large, and if the fineness is small, it is easy to cut in weaving and handling. This auxiliary yarn is used for the purpose of holding parallel flat woven yarns together, and inorganic fibers such as carbon fiber and glass fiber, and organic fibers such as polyaramid fiber, vinylon fiber and polyester fiber can be used. Is not particularly limited.

Here, the fiber density of the woven fabric means a value defined by the following equation. Fiber density of fabric (g / m ³ ) = [weight of fabric (g / m ³ )
m ² )] / [fabric thickness (mm)] The fabric weight (g / m ² ) and the fabric thickness (mm)
Is a value measured according to JIS R7602.

A plurality of layers of the reinforcing fiber material made of such a reinforcing fiber fabric are laminated, impregnated with a resin, and formed into an FRP. The lamination structure of the fabric is not particularly limited, and may be unidirectional or cross lamination. The FRP may be formed by a hand lay-up method performed on site, and may be formed at the time of manufacturing a product that can be formed in advance such as a building panel.

When the reinforcing fiber yarn used for the reinforcing fiber woven fabric is a carbon fiber yarn, the properties of the carbon fiber flat yarn used include:
It is preferable that the tensile modulus is high, the breaking strain energy is high, and the tensile strength (tensile breaking strength) is high. The tensile modulus is preferably 20 × 10 ³ kgf / mm ² or more, and the breaking strain energy is 4.0 mm ·
It is preferably at least kgf / mm ³ . By having a high elastic modulus, a high reinforcing effect can be obtained. Further, by setting the high fracture strain energy, the impact resistance of the molded FRP is improved, and high impact resistance can be exhibited even when an external impact force or an impact force due to an earthquake or the like is applied. The tensile strength of the carbon fiber yarn is preferably 450 kgf / mm ² or more, whereby the strength of the formed FRP is ensured.

In the above, the tensile modulus is JIS-R7
601 is measured. The breaking strain energy (w) is calculated by the following equation, where σ (kgf / mm ² ) is the tensile strength measured in accordance with JIS-R7601 and E is the tensile modulus of elasticity (kgf / mm ² ). σ ² / 2E.

A plurality of layers of the reinforcing fiber material made of the above-described reinforcing fiber fabric are laminated, and the reinforcing fiber material is impregnated with a resin, and molded into a civil engineering / architecture reinforcing member made of FRP. The reinforcing member for civil engineering / architecture may be constituted only by the FRP itself, and a constitution using the FRP, for example,
The FRP and other members may be combined or laminated, or the FRP may be formed as a sandwich structural material provided on both sides of a core material. When a sandwich structure material is used, for example, a foam (for example,
A core material made of a foamed plastic) or a honeycomb structure can also be used.

The matrix resin used in the FRP molding according to the present invention includes thermosetting resins such as epoxy resin, unsaturated polyester resin, vinyl ester resin, polyimide resin and phenol resin. These thermosetting resins, in the state impregnated in the fabric Ru Ah in B stage.

In the civil engineering / architectural reinforcing member according to the present invention, the reinforcing fiber woven fabric used for the FRP molding is a specific flat yarn woven fabric. A member having high mechanical properties, especially high elastic modulus and high impact resistance can be realized. Therefore, the reinforcing member having such excellent characteristics can be applied to reinforcing various civil engineering structures, buildings, materials, panels, and the like.

[0034]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a reinforcing member for civil engineering and construction according to the present invention. FIG.
FIG. 3 shows reinforcement of a road bridge. In FIG. 1, reference numeral 1 denotes a road bridge. The road bridge 1 has a pier 2, a girder 3, and a floor slab 4 made of reinforced concrete. These piers 2, girders 3, and floor slabs 4 are all subject to FRP reinforcement.

For example, as shown in FIG. 2, the pier 2 is reinforced by providing an FRP 6 including the flat yarn woven fabric 5 according to the present invention so as to wind the pier 2. This fabric 5 is
Any of a method of winding or sticking while impregnating the resin, a method of winding or sticking after impregnating the resin, and a method of first putting the prepreg in a prepreg state and winding or sticking the prepreg may be used.

As shown in FIG. 3, the floor slab 4 is reinforced by bonding the FRP 7 according to the present invention to the back surface of the floor slab in a strip and grid pattern. By making the shape of a lattice, drainage or the like can be secured.

In such a reinforcement, while being a lightweight and easy-to-handle member, it can exhibit high mechanical properties due to the inclusion of a woven fabric having a high cover factor, and has excellent resistance to external impact and shocks due to earthquakes and the like. It can exhibit impact properties and provide an excellent reinforcing effect.

FIG. 4 shows a panel member 10 used for an outer wall of a building, for example. In the figure, reference numeral 11 denotes a core material made of cement, concrete, or reinforced concrete, and an FRP 13 including the flat fabric 12 according to the present invention is provided on one or both surfaces of the core material 11. As described above, even in a building panel or the like, an excellent reinforcing effect can be obtained by the reinforcing member according to the present invention. Further, in the FRP according to the present invention, since good surface smoothness is also obtained, a good-looking outer wall or the like is obtained.

The civil and architectural reinforcing member of the present invention is not limited to the above-described example, and can be used for reinforcing any civil engineering structure or building, and the above-described excellent effects can be obtained.

[0040]

As described above, when the reinforcing member for civil and architectural use of the present invention is used, the structure includes the FRP formed by using a specific flat yarn woven fabric, so that the weight reduction and the high strength are achieved. In addition, particularly good surface smoothness and high impact resistance can be obtained, and an excellent reinforcing effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial side view of a road bridge showing a target area to which a civil engineering / architecture reinforcing member of the present invention is applied.

FIG. 2 is a perspective view showing a state of reinforcing a pier of the road bridge of FIG. 1;

FIG. 3 is a perspective view showing a state of floor slab reinforcement of the road bridge of FIG. 1;

FIG. 4 is a perspective view of a building panel as a civil engineering / building reinforcing member according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Road bridge 2 Pier 3 Girder 4 Floor slab 5 Flat yarn fabric 6 FRP 7 FRP 10 Building panel 11 Core material 12 Flat yarn fabric 13 FRP

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI E04G 23/02 B29C 67/14 X (56) References JP-A-6-206223 (JP, A) JP-A-7-118988 ( JP, A) JP-A-7-300739 (JP, A) JP-A-58-191244 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D03D 1/00-27/18

Claims (7)

(57) [Claims] 1. A reinforcing member for civil engineering and construction containing a fiber-reinforced plastic obtained by impregnating a thermosetting resin into a plurality of layers of a reinforcing fiber material, wherein at least one layer of the reinforcing fiber material has a single yarn width. Is 3 to 16 mm, the yarn width / thickness ratio is 20 or more ,
A reinforcing fiber woven fabric in which a reinforcing fiber yarn made of a flat carbon fiber yarn having a breaking strain energy of 4.0 mm · kgf / mm ³ or more is at least one of a warp yarn and a weft yarn, wherein at least one of the warp yarn and the weft yarn is a woven fabric. Civil engineering characterized by consisting of flat yarn woven fabric with fibers in parallel in the state
Building reinforcement. 2. The reinforcing member for civil engineering and construction according to claim 1, wherein a cover factor of the reinforcing fiber fabric is 85% or more. 3. The reinforcing member for civil engineering and construction according to claim 1, wherein the reinforcing fiber fabric is impregnated with a thermosetting resin and is adhered to a surface of an inorganic material. 4. The at least one of the warp yarn and the weft yarn is formed by laminating a plurality of the flat reinforcing fiber yarns.
4. The reinforcing member for civil engineering or construction according to any one of the above-mentioned items. 5. The carbon fiber yarn has a tensile modulus of 20 × 1.
5. The method according to claim 1, which is at least 0 ³ kgf / mm ^2.
Civil and architectural reinforcement members described in any of the above . 6. The carbon fiber yarn has a strength of 450 kgf /
The size of any one of claims 1 to 5, which is not less than mm ^2.
Of civil engineering and construction. 7. fabric basis weight is 100 to 600 / m ² der
The civil and architectural reinforcing member according to any one of claims 1 to 6 .