JP2004249507A - Reinforcing fiber sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing fiber sheet having good resin impregnation properties and workable with good application properties. <P>SOLUTION: The reinforcing fiber sheet 10 is constituted by integrally holding a reinforcing fiber bundle layer 12, which is formed by aligning many reinforcing fiber bundles 11 longitudinally, by a resin-permeable support 13. Each of the reinforcing fiber bundles 11 is formed by longitudinally bundling fiber strands 14, which are formed by unidirectionally aligning many reinforcing fibers (f), by bundling members 15. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
INDUSTRIAL APPLICABILITY The present invention reinforces a concrete structure or a steel structure (hereinafter, simply referred to as a "structure" including a concrete structure, a steel structure, etc.) which is a civil engineering building structure such as a bridge or an elevated road. As a reinforcing material, the resin impregnating property is good, it can be reinforced with good workability at the reinforcement site and the reinforcing strength is improved, and further, the resin impregnating property is good in the production of the intermediate base material of the FRP molded product It relates to a fiber sheet.
[0002]
[Prior art]
In recent years, for example, as a method of reinforcing a structure, an adhesive construction method of attaching or winding a continuous reinforcing fiber sheet to the surface of an existing or newly-installed structure has been developed. In such a bonding method, a unidirectionally reinforced fiber sheet as described in Patent Literature 1 and Patent Literature 2 is used.
[0003]
That is, as shown in FIG. 7, the unidirectionally arrayed reinforcing fiber sheet includes a resin-permeable support sheet 13 and reinforcing fibers f held in the support sheet 13 and arranged in one direction. And a reinforcing fiber layer 12A to be formed.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 3-222732 [Patent Document 2]
JP-A-3-224901
[Problems to be solved by the invention]
As described above, in the unidirectionally reinforced fiber sheet 10A having the above-described configuration, it is necessary to impregnate the reinforcing fiber layer 12A with a resin at a reinforcing site and adhere the resin to the structure.
[0006]
According to the results of the research experiments conducted by the present inventors, when the fiber weight of the reinforcing fiber layer 12A is about 300 g / m ² or less, there is no problem in the resin impregnating property. When 300 to 1000 g / m ² was required, it was found that the thickness of the sheet was large, the resin impregnation was poor, and there was a problem in workability.
[0007]
For this reason, at present, a plurality of unidirectionally reinforced fiber sheets having a basis weight of about 200 to 300 g / m ² are prepared, and the sheets are inevitably stuck to a surface to be reinforced and impregnated with a resin. Have been. Therefore, when the reinforcement strength is increased, it takes a long time to perform the construction, and the operation cost becomes large. Also, the cost for the unidirectionally reinforced fiber sheet used is the more advantageous if one can work with one sheet.
[0008]
Therefore, an object of the present invention is to provide a reinforced fiber sheet which has good resin impregnation and can be operated with good workability.
[0009]
Another object of the present invention is to provide a reinforced fiber sheet having a good resin impregnation property and a large basis weight of 300 g / m ² or more.
[0010]
[Means for Solving the Problems]
The above object is achieved by a reinforcing fiber sheet according to the present invention. In summary, the present invention is a reinforcing fiber sheet in which a reinforcing fiber bundle layer formed by aligning a large number of reinforcing fiber bundles along the longitudinal direction is integrally held by a resin-permeable support,
The reinforcing fiber bundle is a reinforcing fiber sheet formed by bundling fiber strands formed by aligning a large number of reinforcing fibers in one direction along a longitudinal direction by a bundling member.
[0011]
According to one embodiment of the present invention, the reinforcing fiber bundle forms a cross-sectional area of the reinforcing fiber bundle surrounded by an inner peripheral portion of the bundle member as Sb, and forms the fiber strand surrounded by the bundle member. Assuming that the sum of the cross-sectional areas of the reinforcing fibers to be formed is Ss, the porosity Sr = (Sb-Ss) / Sb is 30 to 90%.
[0012]
According to another embodiment of the present invention, the fiber strand is formed by converging 1,000 to 100,000 reinforcing fibers.
[0013]
According to another embodiment of the present invention, the basis weight of the reinforcing fiber bundle layer is 100 to 1000 g / m ² .
[0014]
According to another embodiment of the present invention, the binding member is a wire, a string, or a tape.
[0015]
According to another embodiment of the present invention, the resin-permeable support is arranged on one side or both sides of the reinforcing fiber bundle layer and adhered. The resin-permeable support may be a biaxial or triaxial mesh support sheet, a cloth, or a weft having only one axis in a 90 ° direction with respect to the longitudinal direction of the reinforcing fiber bundle layer. . According to another embodiment, the resin-permeable support is adhered to the reinforcing fiber bundle forming the reinforcing fiber bundle layer by a resin coated on a surface of a yarn constituting the resin-permeable support. .
[0016]
According to another embodiment of the present invention, the reinforcing fibers constituting the reinforcing fiber bundle are inorganic fibers such as carbon fibers, glass fibers, alumina fibers, and Tyranno fibers, or aramid fibers, polyethylene fibers, PBO (polyparaphenylene). Organic fibers such as benzobisoxazole) fibers, polyamide fibers, polyarylate fibers, and polyester fibers, or steel fibers can be used alone or in combination.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the reinforcing fiber sheet according to the present invention will be described in more detail with reference to the drawings.
[0018]
Example 1
1 to 3 show one embodiment of the reinforcing fiber sheet according to the present invention. According to the present embodiment, the reinforcing fiber sheet 10 is disposed on one surface of the reinforcing fiber bundle layer 12 formed by aligning a large number of reinforcing fiber bundles 11 along the longitudinal direction, and is reinforced. And a resin permeable support 13 integrally holding the fiber bundle layer 12. The resin-permeable support 13 may be provided on both surfaces of the reinforcing fiber bundle layer 12. Next, the reinforcing fiber bundle 11 will be further described.
[0019]
As can also be better understood with reference also to FIG. 4, according to the invention, the reinforcing fiber bundle 11 comprises a large number of reinforcing fibers f, for example from 1000 to 100,000, generally from 1000 to 24000. Are aligned in one direction, preferably arranged in a parallel state so that the fibers do not overlap, or as necessary, loosely twisted and converged with the fiber strand 14, and the outer periphery of the fiber strand is loosely bundled. It is constituted by a bundling member 15.
[0020]
The bundling member 15 is a wire having a wire diameter of approximately 0.01 mm to 1 mm, or a string or tape having a width of approximately 1 mm to 5 mm and a thickness of approximately 0.01 mm to 0.1 mm. Further, the bundling member 15 can be formed by converging a plurality of reinforcing fibers f of the same or different types as the reinforcing fibers f forming the fiber strands 14, but depending on the case, it may be a linear or tape-like material such as copper or steel. Metal material can be used.
[0021]
In the present embodiment shown in FIGS. 1 to 3, the two strands 15 are used as the binding member 15 and the fiber strands 14 are bound by overwinding. However, the present invention is not limited to this. The number may be one, or three or more wires may be used. It is also possible to use a tape as described above.
[0022]
According to the present invention, the bundling member 15 loosely bundles the outer periphery of the fiber strand 14. That is, with reference to FIG. 4, the sectional area of the reinforcing fiber bundle 11 surrounded by the inner peripheral portion of the bundle member 15 is represented by Sb, and the reinforcing fibers f forming the fiber strand 14 surrounded by the bundle member 15. Assuming that the sum of the cross-sectional areas fs is Ss, the porosity Sr = (Sb-Ss) / Sb is 0.3 to 0.9 (i.e., 30 to 90%), preferably 0.4 to 0. 8 (that is, 40 to 80%). The void indicated by the void ratio Sr exists inside the reinforcing fiber bundle 11.
[0023]
In the present embodiment, the reinforcing fibers f constituting the reinforcing fiber bundle 11 are made of inorganic fibers such as carbon fibers, glass fibers, alumina fibers, and Tyranno fibers, or aramid fibers, polyethylene fibers, and PBO (polyparaphenylenebenzobisoxazole). ) Organic fibers such as fibers, polyamide fibers, polyarylate fibers, and polyester fibers, and further, steel fibers and the like can be used alone or in combination.
[0024]
The resin-permeable support 13 can be a biaxial or triaxial mesh support sheet or cloth, but in this embodiment, as shown in FIG. used. The vertical and horizontal intervals between the threads 16 and 17 of the biaxial mesh support sheet 13 are usually about 1 to 100 mm, but preferably 2 to 50 mm. In addition, the resin-permeable support 13 can be a so-called uniaxial sheet in which the weft yarns 17 are arranged only in a direction at 90 ° to the longitudinal direction of the reinforcing fiber bundle 11.
[0025]
In the description of the above embodiment, the reinforcing fiber bundle 11 and the resin permeable support 13 constitute a mesh support sheet when a mesh support sheet is used as the resin permeable support 13, for example. The surfaces of the warp yarns 16 and the weft yarns 17 are impregnated in advance with a low-melting type thermoplastic resin, and the mesh-like support sheet 13 is laminated on one or both sides of the reinforcing fiber bundle layer 12 and heated and pressed to form a mesh-like support. The portions of the warp yarns 16 and the weft yarns 17 of the sheet 13 are welded (resin-bonded) to the reinforcing fiber bundle layer 12 so that the mesh-like support sheet 13 and the reinforcing fiber bundle layer 12 can be integrated.
[0026]
Even when a cloth or a uniaxial sheet (weft) is used as the resin-permeable support 13, the reinforcing fiber bundle layer 12, that is, the reinforcing fiber bundle 11 can be held in the same manner.
[0027]
In the reinforcing fiber sheet of the present invention, the reinforcing fiber bundle 11 constituting the reinforcing fiber bundle layer 12 is held by the resin-permeable support 13 on one side because the fiber strands 14 are loosely restrained by the bundle members 15. Just do it, it won't break. Therefore, it is excellent in handleability and advantageous in manufacturing cost. In addition, in this case, when the configuration is such that both side surfaces are held, compression of the reinforcing fiber sheet at the time of manufacturing is avoided, and deterioration of resin impregnation due to compression of the reinforcing fiber sheet can be prevented.
[0028]
According to the present invention, the reinforcing fiber bundle layer 12 is formed by aligning a large number of reinforcing fiber bundles 11 along the longitudinal direction. Can be formed in one layer, but the present invention is not limited to this, and the reinforcing fiber bundle 11 can be formed by laminating multiple layers.
[0029]
The reinforcing fiber sheet 10 produced according to the present invention as described above has a sheet thickness such that the fiber weight of the reinforcing fiber bundle layer 12 is 100 g / m ² or more, particularly 300 g / m ² or more and 1000 g / m ² or less. The thickness can be made sufficiently large, and the resin impregnation property can be significantly improved.
[0030]
That is, when a conventional reinforcing fiber sheet 10A as shown in FIG. 7 is impregnated with a resin from one side of the reinforcing fiber sheet 10A as shown in FIG. 6, the reinforcing fiber f becomes a resin permeable support. 13 (not shown in FIG. 6), the resin is difficult to penetrate to the opposite side because it is uniformly arranged in a dense state.
[0031]
On the other hand, according to the reinforcing fiber sheet 10 of the present invention, the reinforcing fiber bundle layer 12 is formed by aligning a large number of reinforcing fiber bundles 11 along the longitudinal direction. Even when the reinforcing fiber bundles 11 are closely arranged, small gaps (g) are generated between them. According to the measurement by the present inventors, the gap (g) was 0.1 mm to 5.0 mm. Therefore, in the reinforcing fiber sheet 10 of the present invention, as shown in FIG. 5, when the resin is impregnated, the reinforcing fiber f is impregnated with the resin, and even if the reinforcing fiber f is moved, the reinforcing fiber f is Since it is constrained, further movement is suppressed, so that the gap (g) formed between the adjacent reinforcing fiber bundles 11 and 11 is not closed. Therefore, the resin can easily pass through the gap (g) between the reinforcing fiber bundles 11, that is, the passage of the resin, and the resin can penetrate from around the bundle member 15 and be easily impregnated.
[0032]
Next, an experimental example of the reinforcing fiber sheet 10 of the present invention will be described.
[0033]
Experimental example 1
Using the reinforcing fiber sheet 10 of the present invention, a concrete beam was reinforced according to the bonding method.
[0034]
In this experimental example, the reinforcing fiber sheet 10 having the configuration described with reference to FIG. 1 was used. As the fiber strand 14 in the reinforcing fiber sheet 10, a PAN-based carbon fiber strand having an average diameter of 7 μm and a converging number of 24,000 was used as the reinforcing fiber f. The fiber strands 14 were bundled as shown in FIG. 3 by a bundle member 15 having a wire diameter of 0.1 mm and produced using the same reinforcing fiber f, thereby producing a reinforcing fiber bundle 11.
[0035]
The reinforcing fiber bundles 11 were arranged on a mesh-like support sheet 13 and adhered. Thus, a reinforcing fiber bundle layer 12 having a fiber weight of 600 g / m ² was produced.
[0036]
The mesh-like support sheet 13 was a biaxial mesh-like support sheet using glass fibers (300d, count of 1/10 mm) as warp yarns 16 and weft yarns 17. The interval between the warp yarns 16 and the weft yarns 17 of the biaxial mesh support sheet 13 was 10 mm.
[0037]
The reinforcing fiber sheet 10 thus manufactured had a width (W) of 500 mm and a length in the axial direction of 100 m. In addition, a gap (g) of 0.3 to 0.4 mm was generated between the reinforcing fiber bundles 11.
[0038]
Next, the reinforcing fiber sheet 10 was used to bond to a concrete beam. That is, the reinforcing fiber sheet 10 was applied to the surface to which the concrete beam sheet having a length of 10 m was adhered, and the matrix resin was applied from the reinforcing fiber sheet side and impregnated.
[0039]
Regarding the resin impregnating property, sufficient impregnation was obtained in a time equivalent to that of a fiber having a basis weight of 300 g / m ² , and the finish was extremely good. The desired reinforcement strength was obtained.
[0040]
【The invention's effect】
As described above, the present invention is a reinforcing fiber sheet in which a plurality of reinforcing fiber bundles are formed by aligning a plurality of reinforcing fiber bundles in the longitudinal direction and integrally held by a resin-permeable support. The reinforcing fiber bundle is formed by bundling fiber strands formed by aligning a large number of reinforcing fibers in one direction by a bundling member along the longitudinal direction, so that the resin impregnation property is good and work is performed with good workability. be able to. Further, it is also possible to provide a reinforced fiber sheet having good resin impregnation and a large basis weight of 300 g / m ² or more.
[Brief description of the drawings]
FIG. 1 is a perspective view showing one embodiment of a reinforcing fiber sheet according to the present invention.
FIG. 2 is a cross-sectional view of one embodiment of a unidirectionally reinforced fiber sheet according to the present invention.
FIG. 3 is a perspective view showing one embodiment of a reinforcing fiber bundle.
FIG. 4 is a cross-sectional view of one embodiment of a reinforcing fiber bundle.
FIG. 5 is a diagram illustrating a mode of resin impregnation in the reinforcing fiber sheet according to the present invention.
FIG. 6 is a view for explaining a mode of resin impregnation in a conventional unidirectionally reinforced fiber sheet.
FIG. 7 is a perspective view illustrating a conventional unidirectionally reinforced fiber sheet.
[Explanation of symbols]
Reference Signs List 10 reinforcing fiber sheet 11 reinforcing fiber bundle 12 reinforcing fiber bundle layer 13 resin-permeable support 14 fiber strand 15 bundling member

Claims (9)

A reinforcing fiber sheet in which a plurality of reinforcing fiber bundles are formed integrally by a resin-permeable support and a reinforcing fiber bundle layer formed by aligning the reinforcing fiber bundles in the longitudinal direction,
The reinforcing fiber sheet is characterized in that the reinforcing fiber bundle is formed by bundling fiber strands formed by aligning a large number of reinforcing fibers in one direction in a longitudinal direction by a bundling member. The reinforcing fiber bundle has a cross-sectional area Sb of the reinforcing fiber bundle surrounded by an inner peripheral portion of the bundling member, and a sum of cross-sectional areas of reinforcing fibers forming the fiber strand surrounded by the bundling member. 2. The reinforcing fiber sheet according to claim 1, wherein the porosity Sr = (Sb−Ss) / Sb is 30 to 90% when Ss. The reinforcing fiber sheet according to claim 1, wherein the fiber strand is formed by converging 1,000 to 100,000 reinforcing fibers. 4. The reinforcing fiber sheet according to claim 1, wherein the fiber weight of the reinforcing fiber bundle layer is 100 to 1000 g / m ^{2. 5} . The reinforcing fiber sheet according to any one of claims 1 to 4, wherein the binding member is a wire, a string, or a tape. The reinforcing fiber sheet according to any one of claims 1 to 5, wherein the resin-permeable support is arranged on one side or both sides of the reinforcing fiber bundle layer and is adhered. The resin-permeable support is a biaxial or triaxial mesh support sheet, a cloth, or a weft having only one axis in a 90 ° direction with respect to the longitudinal direction of the reinforcing fiber bundle layer. The reinforced fiber sheet according to any one of claims 1 to 6. The resin permeable support is adhered to the reinforcing fiber bundle forming the reinforcing fiber bundle layer by a resin coated on a surface of a yarn constituting the resin permeable support. The reinforced fiber sheet according to any one of Items 1 to 7. The reinforcing fibers constituting the reinforcing fiber bundle are inorganic fibers such as carbon fibers, glass fibers, alumina fibers, and Tyranno fibers, or aramid fibers, polyethylene fibers, PBO (polyparaphenylene benzobisoxazole) fibers, polyamide fibers, and poly fibers. The reinforcing fiber sheet according to any one of claims 1 to 8, wherein an organic fiber such as an arylate fiber or a polyester fiber, a steel fiber, or the like is used alone or in combination of two or more.

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