JPH08337942A - Reinforcing member for engineering and building work - Google Patents

Abstract

PURPOSE: To obtain excellent reinforcing effect by constructing a member containing FRP using a specific reinforced fiber woven fabric in reinforcing member for engineering and building works. CONSTITUTION: A resin is impregnated into a reinforced fiber material having plural layers to provide the objective reinforcing member 2 for engineering and building works containing a fiber-reinforced plastic 6. A reinforced fiber material having at least one layer is formed into a reinforced fiber fabric in which flat reinforced fiber having 3-16mm yarn width of single yarn and >=20 ratio of yarn width/thickness ratio is used as either one of warp and weft and at least one of warp and weft is parallel arranged in a state of a fabric.

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 in particular, reinforcement of bridge piers, girders, floor slabs and the like of road bridges using fiber reinforced plastic (hereinafter also referred to as FRP), pillars of reinforced concrete structures. The present invention relates to a reinforcing member for civil engineering / construction, which is suitable for reinforcing walls, walls, and panels for construction.

[0002]

2. Description of the Related Art FRP, which is lightweight and has excellent mechanical properties, is beginning to receive attention as a reinforcing member for civil engineering and construction. Among them, a carbon fiber reinforced plastic (hereinafter also referred to as CFRP) using carbon fibers having a large specific elastic modulus and a large specific strength exhibits high mechanical properties.

For example, recently, piers and floor slabs of road bridges,
The girders have deteriorated due to rust of reinforcing bars, fatigue of reinforcing bars and neutralization of concrete, which is a problem. The reinforcement is
Usually, it is performed by attaching a steel plate to concrete or a beam with an adhesive, but this work often has to be performed in a narrow space surrounded by the beam. However, the steel plate is heavy, and a hoist such as a crane truck is required for attachment, which is complicated, and sometimes the hoist cannot be used. In addition, the concrete surface is not necessarily smooth, and has an uneven surface. Therefore, in order to completely bond the steel plate and the concrete, it is necessary to thicken the adhesive layer to eliminate the influence of the unevenness of the concrete surface, which is very inefficient.

On the other hand, recently, the FRP reinforcement method for reinforcing bridge piers, floor slabs, girders, etc. of road bridges with FRP plates has attracted attention because it enables reinforcement work without blocking the passage of vehicles. There is. This method applies resin directly to the concrete surface so that it can be sufficiently reinforced even if there is some unevenness on the concrete surface, and then impregnates and cures the resin into, for example, a unidirectional sheet-shaped fiber reinforcement. Then, the fiber-reinforced plastic plate is molded, and at the same time, the FRP plate is adhered to the concrete by a so-called hand lay-up molding method. Unlike the steel plate reinforcement method, there is no need to carry heavy objects, so work efficiency is good and FRP molding can be performed on site. Similarly, for the reinforcement of columns and walls of reinforced concrete buildings, and also for the reinforcement of building panels, the method of reinforcement using FRP plates has begun to attract attention.

Such an FRP reinforcing member is usually formed by molding a plurality of layers of reinforcing fiber material with a resin, but it is easy to handle before molding, at the time of molding, and conforms to the mold. A reinforced fiber woven fabric in the form of a woven fabric is often used as a reinforced fiber material in terms of easiness, excellent properties as an FRP after molding and the like.

By the way, the higher the fineness of the carbon fiber yarn is, the more the productivity in the precursor and the flameproofing process and the firing process is improved, and the carbon fiber yarn can be manufactured at low cost.

However, since the ordinary reinforced fiber woven fabric is made by using the reinforced fiber yarns in which the reinforced fibers are bundled into a substantially circular cross section, in the woven state, the warp yarns and the weft yarns are mixed in the intersecting portion. The cross section of the reinforcing fiber yarn is elliptical, and the woven yarn is crimped greatly. In particular, in a reinforced fiber woven fabric using thick reinforced fiber yarns, this tendency becomes large because thick weft yarns and thick warp yarns are interlaced.

Therefore, in the reinforced fiber woven fabric in which the reinforced fiber yarn is largely crimped, the fiber density becomes non-uniform and high mechanical properties cannot be sufficiently exhibited. Further, when the reinforcing fiber yarn is largely crimped, the surface smoothness of the molded FRP is not good. Civil engineering and building structures often require good surface smoothness. Further, a reinforced fiber woven fabric using thick reinforced fiber yarns generally has a large fabric weight and a large thickness, resulting in poor resin impregnation property when molding a prepreg or FRP.

Therefore, FRP and CFRP obtained by using a reinforced fiber woven fabric obtained by weaving thick reinforced fiber yarns have many voids present in the resin, and high mechanical properties cannot be expected.

On the other hand, when a thick reinforcing fiber yarn is used to reduce the fabric weight, the voids formed between the reinforcing fiber yarns become large. Therefore, when FRP or CFRP is formed by using a reinforced fiber woven fabric having a small fabric weight, the volume content of the reinforced fibers becomes low and voids of the resin are concentratedly generated in the voids formed between the reinforced fiber yarns. However, there is a drawback that a high-performance composite material cannot be obtained.

[0011]

The present invention pays attention to such a situation, and in particular, in a civil engineering / construction reinforcing member using FRP, the F member using a specific reinforced fiber woven fabric is used.
By using a member containing RP, it is intended to obtain a desired high reinforcing effect and to obtain good surface smoothness.

[0012]

[Means for Solving the Problems] A civil engineering / building reinforcing member of the present invention which meets the above object is a civil engineering / building reinforcing member containing a fiber reinforced plastic obtained by impregnating a plurality of layers of reinforcing fiber material with a resin. And at least one layer of reinforcing fiber material,
A reinforced fiber woven fabric having a flat yarn having a yarn width of 3 to 16 mm and a yarn width / thickness ratio of 20 or more as 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. It consists of a flat yarn woven fabric in which the fibers are parallel in the state.

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

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. By doing so, it is possible to fabricate a fabric having a large basis weight, and it is possible to mold an FRP having a larger fiber volume content.

As the reinforcing fiber yarn, various reinforcing fiber yarns such as carbon fiber yarn, glass fiber yarn and polyaramid fiber yarn can be used, but carbon fiber yarn having high elastic modulus and high strength is particularly preferable. The flat reinforcing fiber yarn is usually in the form of a multifilament yarn.

The woven yarn of the woven fabric made of such flat reinforcing fiber yarns needs to have substantially no twist and the fibers are parallel to each other. Here, "substantially no twist" means
A state in which there is no twist of 1 turn or more per 1 m of yarn length. In other words, it means a realistic untwisted state. It is necessary that the woven state is substantially untwisted. for that purpose,
A bobbin of untwisted flat reinforcing fiber yarn is unwound and unwound, and warps and wefts are supplied so as to prevent untwisting, and a woven fabric is obtained.

When the woven yarn is twisted, the yarn width is narrowed at the twisted portion to be bundled and thickened, and unevenness occurs on the surface of the woven fabric. Therefore, when the woven fabric is woven, stress concentrates on the twisted portion when an external force acts, and
When it is molded into the same shape, the mechanical properties become non-uniform.

The flat reinforcing fiber yarn has a yarn width of 3 to 16 m.
The range is m. A yarn width in this range is easy to weave, and an optimum flattened state is easily obtained in relation to the yarn thickness. The yarn width / thread thickness ratio is 20 or more. When it is less than 20, it is difficult to suppress the crimp of the woven yarn to a minimum when trying to obtain a high cover factor.

In such an optimal flattened reinforcing fiber woven fabric made of a yarn having substantially no twist, even if the fineness of the yarn is increased, the crimp at the intersecting portion of the yarns can be suppressed to be extremely small. High strength characteristics can be obtained when FRP or CFRP is used. The crimp is small, so FRP and CF
The surface smoothness of RP is good, and the desired surface form of the reinforcing member for civil engineering and construction can be easily obtained. In addition, since the fineness of the woven yarn can be increased, the woven yarn, and thus the reinforced fiber woven fabric, can be manufactured at a lower cost.

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

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

[0022] Here, the cover factor Cf (%), a factor related to the size of the gap portion formed between weaving yarns, when setting a region of area S ₁ on the textile, the area S ₁
When the area of the void portion formed in the yarn in the inner and S _2, refers to a value 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 warp threads and weft threads made of thin flat reinforcing fiber threads. Therefore,
A woven fabric with a small dropout degree, that is, a large cover factor. When an FRP is molded using such a reinforced fiber woven fabric having a large cover factor, a uniform molded product is obtained, and voids in the resin and uneven fiber distribution such as stress concentration do not occur.

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

When the flat reinforcing fibers are woven into warp and weft, the fabric weight is 100 to 300.
It is preferably g / m ² . Further, in the case of a woven fabric in which at least one of the warp yarn and the weft yarn is a flat reinforcing fiber yarn, when at least one of the warp yarn and the weft yarn is a fabric in which a plurality of flat reinforcing fiber yarns are laminated, Is preferably 200 to 600 g / m ² .
Since it is a flat woven yarn, the crimp can be suppressed to a small level even if the yarn is woven in such a laminated state. Then, the fiber density of the woven fabric can be increased by the lamination.

Further, it is also possible to form a fabric using auxiliary threads. As the auxiliary yarn, it is preferable to use a flat woven yarn made 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, the auxiliary yarn is easily cut during weaving or handling. This auxiliary yarn is used for the purpose of integrally holding parallel flat woven yarns, and inorganic fibers such as carbon fiber or glass fiber, organic fibers such as polyaramid fiber, vinylon fiber, polyester fiber can be used. There is no particular limitation regarding.

Here, the fiber density of the woven fabric means a value defined by the following equation. Textile fiber density (g / m ³ ) = [texture weight (g / m ³
m ² )] / [woven fabric thickness (mm)] Note that the fabric weight (g / m ² ) and the fabric thickness (mm)
Are values measured in accordance with JIS R7602.

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

When the reinforcing fiber yarn used in the reinforcing fiber fabric is a carbon fiber yarn, the characteristics of the carbon fiber flat yarn to be used are:
It is preferable that the tensile elastic modulus is high, the breaking strain energy is large, and the tensile strength (tensile breaking strength) is high. The tensile elastic 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. In addition, the high fracture strain energy improves the impact resistance of the molded FRP, and can exhibit high impact resistance 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, which ensures the strength of the FRP to be molded.

In the above, the tensile modulus is JIS-R7.
It is measured according to 601. Breaking strain energy (w) is the tensile strength measured in conformity with JIS-R7601 σ (kgf / mm 2), when the tensile modulus and E (kgf / mm ^2), wherein, w = It is defined by σ ² / 2E.

A plurality of reinforced fiber materials made of the reinforced fiber woven fabric as described above are laminated, and the reinforced fiber materials are impregnated with a resin to form a reinforcing member for civil engineering / construction made of FRP. The civil engineering / construction reinforcing member may be composed of only the FRP itself, or a structure using the FRP, for example,
The FRP and other members may be combined or laminated, and further, the FRP may be configured as a sandwich structure material provided on both surfaces of a core material. In the case of a sandwich structure material, the core material is, for example, a foam (for example,
A core material made of 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 are B stage when impregnated into the fabric. As the matrix resin, nylon resin,
Polyester resin, polybutylene terephthalate resin,
Thermoplastic resins such as polyetheretherketone (PEEK) resin and bismaleimide resin can also be used.

In the reinforcing member for civil engineering and construction according to the present invention, since the reinforced fiber woven fabric used for the FRP molding is a specific flat yarn woven fabric, not only weight saving but also excellent surface smoothness and It is possible to realize a member having mechanical properties, particularly a high elastic modulus and high impact resistance. Therefore, the reinforcing member having such excellent properties can be applied to the reinforcement of various civil engineering structures, buildings, materials, panels and the like.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The civil engineering / building reinforcing member according to the present invention will be specifically described below with reference to the drawings. FIG.
3 to 3 show the reinforcement of road bridges. In FIG. 1, reference numeral 1 denotes a road bridge, which has a pier 2, a girder 3, and a floor slab 4, which are made of reinforced concrete. The pier 2, girder 3, and floor slab 4 are all subject to reinforcement by FRP.

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

Further, the floor slab 4 is reinforced by, for example, as shown in FIG. 3, bonding the FRP 7 according to the present invention to the back surface in a strip shape and a grid shape. By making a grid, drainage etc. can be secured.

In such reinforcement, while being a lightweight and easy-to-handle member, it can exhibit high mechanical properties because it contains a woven fabric with a high cover factor, and it has excellent resistance to external impact force and impact from earthquakes, etc. It is possible to exhibit impact resistance and obtain an excellent reinforcing effect.

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

The civil / construction reinforcing member of the present invention is not limited to the examples described above, but can be used to reinforce any civil engineering structure or building, and the above-mentioned excellent effects can be obtained.

[0040]

As described above, according to the reinforcing member for civil engineering and construction of the present invention, since it is configured to include the FRP formed by using the specific flat yarn woven fabric, it is possible to achieve the weight reduction and the high strength. At the same time, particularly good surface smoothness and high impact resistance can be obtained, and an excellent reinforcing effect can be obtained.

[Brief description of drawings]

FIG. 1 is a partial side view of a road bridge showing locations to which a reinforcing member for civil engineering and construction of the present invention is applied.

FIG. 2 is a perspective view showing a state of reinforcement of a pier of the road bridge of FIG.

FIG. 3 is a perspective view showing how the floor bridge of the road bridge of FIG. 1 is reinforced.

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]

 1 Road bridge 2 Bridge pier 3 Girder 4 Floor slab 5 Flat yarn fabric 6 FRP 7 FRP 10 Construction panel 11 Core material 12 Flat yarn fabric 13 FRP

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area E04G 23/02 7310-4F B29C 67/14 X

Claims (9)

[Claims] 1. A reinforcing member for civil engineering and construction, comprising a fiber-reinforced plastic obtained by impregnating a plurality of layers of a reinforcing fiber material with a resin, wherein at least one layer of the reinforcing fiber material has a single yarn width of 3 to A reinforcing fiber woven fabric having a flat reinforcing fiber yarn of 16 mm and a yarn width / thickness ratio of 20 or more as at least one of a warp yarn and a weft yarn, and at least one of the warp yarn and the weft yarn is a woven fabric in which fibers are parallel to each other. A reinforcing member for civil engineering and construction, which is made of a flat yarn woven fabric. 2. The reinforcing member for civil engineering and construction according to claim 1, wherein the reinforced fiber fabric has a cover factor of 85% or more. 3. The reinforcing member for civil engineering and construction according to claim 1, wherein the reinforced fiber woven fabric is impregnated with a resin and is bonded to the surface of an inorganic material. 4. At least one of the warp yarn and the weft yarn is formed by laminating a plurality of the flat reinforcing fiber yarns.
The civil engineering / construction reinforcing member according to any one of 1 to 3. 5. The reinforcing fiber yarn is composed of carbon fiber yarn.
The civil engineering / construction reinforcing member according to any one of claims 1 to 4. 6. The tensile modulus of the carbon fiber yarn is 20 × 1.
The civil engineering / construction reinforcing member according to claim 5, which has a content of 0 ³ kgf / mm ² or more. 7. The civil / construction reinforcing member according to claim 5, wherein the breaking strain energy of the carbon fiber yarn is 4.0 mm · kgf / mm ³ or more. 8. The strength of the carbon fiber yarn is 450 kgf /
The civil engineering / construction reinforcing member according to any one of claims 5 to 7, having a size of at least mm ² . 9. The reinforcing member for civil engineering and construction according to claim 5, wherein the fabric weight is 100 to 600 g / m ² .