JP2001146815A - Fiber sheet for reinforcement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high strength biaxial reinforcing fiber sheet for reinforcing a building capable of providing a high reinforcing strength, excellent resin impregnating ability, and easiness in handling in execution of work. SOLUTION: This fiber sheet for reinforcement comprises a textile formed of high strength fibers of 16 cN/dtex or more in tensile strength, and the textile cover factor Cf thereof shown by expression (a) is 800 to 1500, the cross rate Ct shown by expression (b) is 10 to 30%, the air permeability is 5 to 20 cm3/cm2. sec., and vertical and horizontal strengths are at least 35 t/m, respectively. Cf=(DW)1/2×Nw+(Df)1/2Nf---(a) Where, Cf: Textile cover factor, Dw: Warp fineness, (dtex) Df: Weft fineness, (dtex) Nx: Warp density (no. of warps/cm), and Nf: Weft density (no. of wefts/cm). Ct=(i×100)/(i+y)----(b) Where Ct: Cross rate (%), i: Number of crossing of warps and wefts of prefect structure, and y: Number of warps of perfect structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing fiber sheet, and more particularly, to a high strength bi-directional structure of a concrete structure such as a floor slab, a pier or a building, and a stone or brick such as a lighthouse or a chimney. The present invention relates to a reinforcing fiber sheet.

[0002]

2. Description of the Related Art Although there are many concrete structures such as general roads and highways, there is a need for seismic reinforcement against destruction due to an earthquake and improvement in durability due to an increase in traffic volume.

In addition, there are structures such as stone lighthouses and brick buildings, which are historic buildings, and chimneys made of concrete and bricks, which require a prolonged life and seismic reinforcement.

In order to reinforce concrete columns such as railway overpasses, for example, a concrete surface is covered with an iron plate, a reinforcing fiber sheet such as aramid fiber or carbon fiber is stuck to the wall surface of the structure with a resin, or There is a method of winding and reinforcing and repairing.

[0005] The method of covering with a steel plate requires a heavy machine and a strong scaffold to handle heavy steel plates, which is a large-scale construction. The method of wrapping a reinforcing fiber sheet such as aramid fiber or carbon fiber has the advantage that there is no need to handle heavy objects, so there is no need for heavy equipment and large-scale scaffolding, and construction is easy, and construction in narrow spaces is also easy. .

[0006] Japanese Patent Application Laid-Open No. Hei 5-332030 proposes a method in which a plurality of carbon fibers are impregnated with a resin and a fiber-reinforced sheet arranged in one direction is wound one by one around a pillar.

[0007] In the case where such a unidirectional sheet is used to reinforce a wall or a floor panel in two directions, at least two sticking operations in a vertical direction and a horizontal direction are required, which is not efficient.

[0008] JP-A-8-218645 discloses a fiber having a tensile strength greater than that of concrete in the length direction.
Reinforcing tapes woven using fibers having a higher tensile modulus in the width direction than in the length direction have been proposed.

Japanese Patent Application Laid-Open No. 6-288099 discloses that reinforcing fibers such as carbon fibers are woven into a long cloth with a plain weave structure, wound around a concrete structure, and the impregnated resin is cured and reinforced. A way to do that has been proposed.

The reinforcing method using a bidirectional sheet using reinforcing fibers in the vertical and horizontal directions is more efficient in operation than a unidirectional sheet, and is superior to using a unidirectional sheet. However, the publication does not disclose the proof stress (tensile strength) of the reinforcing sheet, the number of laminated sheets, and the resin impregnating property which is important as a reinforcing fiber sheet. Further, a plain woven fabric having a high yield strength uses a yarn with a large fineness, so that the ratio of the constituent yarns is high and the impregnating property of the resin is inferior, so that it is not suitable as a high-strength reinforcing sheet.

Japanese Patent Application Laid-Open No. Hei 10-37051 discloses that a fiber group in which reinforcing fibers are arranged in parallel is taken as one unit, which is arranged side by side at intervals, and bound by auxiliary fibers. A bidirectional reinforcing fiber sheet with a so-called warp knitting structure has been proposed. This method is
Since only the reinforcing fibers arranged in the weft are bound by the auxiliary fibers, and the warp and weft are not interlaced with each other, the bonding between the layers between the warp and weft is not sufficient, and it is like a road floor. There is a problem in applications requiring a high yield strength.

In general, reinforcing fiber sheets for floors, columns, lighthouses and the like of roads require high-strength reinforcement. The reinforcement is achieved by laminating as many layers as possible when using a fiber sheet with low proof stress, but even in the case of a bidirectional fiber sheet, it is efficient in terms of workability to attach multiple layers of fiber sheets. However, there is a possibility that the laminated state of each laminated sheet or the impregnation of the resin may vary. Also, much work time is required.

By using a fiber sheet having a high yield strength, the workability and work efficiency can be improved.

In particular, when a fiber reinforced sheet is laminated with resin on the lower surface of the floor, not on the running surface of the vehicle, as in the case of reinforcing the floor of an elevated road, the worker climbs on the scaffold. It is necessary to face the stacking work. In other words, the work content is such that the stacking work is performed on the ceiling surface from the bottom upward. In such a difficult operation, it is desirable that the reinforcement be completed with one fiber sheet, but a reinforcing fiber sheet having a high yield strength is required for that purpose.

[0015] A fiber sheet for reinforcing high-strength fibers can be obtained by increasing the fiber density per unit width of the fibers used in the fiber sheet. Is impaired, the adhesive strength between the fiber sheet and the laminated surface of the structure to be reinforced is reduced, and sufficient reinforcement is not achieved. Especially like plain weave,
A woven fabric having many warp / weft intersecting points causes a problem in resin impregnation in a high-strength sheet.

For example, in the reinforcement of the floor of an elevated road, a fiber reinforcing layer having a proof strength of 35 tons / m or more is required. There were no sheets.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to solve the problems of concrete and stone,
High reinforcement strength, good resin impregnation, and good handleability during construction to reinforce flooring and walls of buildings such as brick bridges, roads, lighthouses, chimneys, buildings, etc. An object of the present invention is to provide a biaxial reinforcing fiber sheet.

[0018]

The present invention has solved the above-mentioned problems by using the following means.

(1) Tensile strength is 16 cN / dtex
It consists of a woven fabric comprising the above high-strength fibers, and has the following formula (a)
The woven fabric cover factor (Cf) is 800 to 150
0, and the crossing rate (Ct) represented by the following formula (b) is 10 to 10.
30 (%) and air permeability of 5 to 20 (cm ³ / c
m ² · Sec), and the proof stress in the vertical direction and the horizontal direction is at least 35 (ton / m), respectively.

Cf = (Dw) ^1/2 × Nw + (Df) ^1/2 × Nf --- (a) Cf: Fabric cover factor Dw: Warp fineness (dtex) Df: Weft fineness (dtex) Nw: Warp yarn Density (lines / cm) Nf: Weft density (lines / cm) Ct = (i × 100) / (i + y) Ct: Interlacing rate (%) i: Complete texture Warp / weft intersecting number y: number of warp yarns of perfect structure (2) The twist coefficient of the warp yarn and the weft yarn represented by the following formula (c) is 4000 or less, and the reinforcing fiber sheet according to the above (1), .

K = T (D) ^1/2 −−−−−−−−−−−−− (c) K: twist coefficient T: number of twists (times / m) D: fineness (dtex) ( 3) The fineness of the warp yarn and the weft yarn is 1500 to 150 respectively.
The reinforcing fiber sheet according to the above (1) or (2), which is 5000 (dtex).

(4) The reinforcing fiber sheet according to any one of (1) to (3), wherein the high-strength fiber is a para-aramid fiber.

(5) The reinforcing fiber sheet according to any one of (1) to (4), wherein the para-aramid fiber is polyparaphenylene terephthalamide.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is a woven fabric in which warp yarns and weft yarns are interlaced, so that the warp and the weft yarns are structurally integrated and have high strength without peeling between the warp and the weft yarns. Is a reinforcing fiber sheet.

The high-strength fiber used in the reinforcing fiber sheet of the present invention has a tensile strength of 1 to obtain a high-strength fiber sheet.
Use a fiber of 6 cN / dtex or more.

The high-strength fiber used in the present invention includes, as organic fibers, para-aramid fibers, high-molecular-weight polyethylene fibers, polyarylate fibers, PBO (polybenzobisoxazole) fibers, and the like. Examples of the para-aramid fiber include polyparaphenylene terephthalamide fiber and copolyparaphenylene-3,4'-oxydiphenylene terephthalamide fiber. Inorganic fibers include carbon fiber, stainless steel fiber, glass fiber, etc., but suppleness, lightness, fiber breakage due to friction, etc. are unlikely to occur, and there is no irritation to the skin due to fiber fluff broken off from the reinforcing fiber sheet Organic fibers are preferred because they are easy to handle at construction sites.

In particular, the fineness of a single yarn is from 0.5 dtex to 5 dte.
The para-aramid fiber x is desirable in terms of ease of resin impregnation and ease of handling such as cutting at a construction site.
Among them, polyparaphenylene terephthalamide fiber (trade name “Kevlar” manufactured by Du Pont-Toray Co., Ltd.) is particularly preferable because it has high elasticity as well as strength.

The thickness of the yarn or fiber is represented by dtex (decitex). The weight of a yarn or fiber of length L (m)
(G), the thickness D (dtex) of the thread or fiber
Is D = (W / L) × 10000. The larger the value, the thicker the yarn.

The woven fabric cover factor (Cf) is calculated by the following equation (a) and represents the degree to which the warp and weft constituting the woven fabric cover the projection surface.

Cf = (Dw) ^1/2 × Nw + (Df) ^1/2 × Nf --- (a) Cf: Fabric cover factor Dw: Warp fineness (dtex) Df: Weft fineness (dtex) Nw: Warp Density (lines / cm) Nf: Weft density (lines / cm) The higher the woven fabric cover factor (Cf), the higher the density of fibers constituting the woven fabric. Therefore, when compared with a woven fabric having the same thickness, a reinforcing fiber sheet having a higher yield strength can be obtained as the woven fabric cover factor increases. According to Textile Engineering IV (published by the Japan Society of Textile Machinery, December 1988), page 168, the cover factor of a filament fabric is generally in the range of 300 to 700 when the fineness is expressed in denier. When the fineness is converted into dtex, the cover factor is in the range of 316 to 738.

In the present invention, it is necessary to increase the fiber density in order to obtain a woven fabric having a high yield strength. Unlike a normal woven fabric, the woven fabric cover factor is 800 or more, which is different from a normal filament woven fabric.

In a reinforcing fiber sheet in which a structure is reinforced by impregnation with a resin, the ease of impregnation with the resin is important for the effect of reinforcement and the efficiency of construction work.

The impregnating property of the resin is affected by the density of the warp / weft constituting the fabric and the ratio of the warp / weft binding each other. The lower the density of warp and weft, the more the yarn-
There are many spaces between the yarns and the resin impregnation is good. However,
In order to obtain a high tensile strength of the fabric, the warp / weft density must be increased, which is contrary to the improvement of the resin impregnation. In the present invention, the fabric cover factor is 8
00 or more. Here, by devising a woven fabric structure that reduces the warp / weft restraining ratio, a reinforcing fiber sheet having high yield strength and better resin impregnation properties can be obtained.

The maximum number of warp and weft yarns that can be woven per unit fabric width is called the maximum weaving density.

The maximum weaving density of the woven fabric depends on the thickness of the yarn and the weave structure. The finer the yarn fineness, the more yarns can be arranged, and the higher the maximum weaving density. However, if the fiber fineness is too small, the strength as a woven fabric cannot be increased. Therefore, the fiber fineness of the reinforcing fiber sheet of the present invention is limited in its fineness, and is preferably 1500 (dtex) or more.

The lower the warp / weft crossing ratio, the more the warp / weft is not constrained to each other, so that more warp / weft per unit width of the fabric can be arranged.
The maximum weaving density can be increased. Therefore,
A woven structure with a low weft crossing ratio can increase the cover factor of the woven fabric.

The reinforcing fiber sheet of the present invention has a woven fabric cover factor of 800 to 1600, preferably 9 to 1600.
00 to 1500. Fabric cover factor is 800
If it is less than 1600, a high yield strength fiber sheet cannot be obtained, and if it exceeds 1600, the number of warp and weft yarns becomes extremely small, resulting in a woven structure, which is not realistic.

Next, a description will be given of the ratio at which the fabric structure and the warp / weft bind to each other.

The above-mentioned textile engineering (IV) P142, 1.5 ″
"Textile structure and type" describes the structure and type of the fabric and the complete structure which is the minimum unit of the fabric structure, and the design diagram which is the expression method. According to the literature, the woven fabric is formed by interlacing the warp and the weft.The arrangement of the warp on the weft is called "floating" .The fabric is expressed as follows using grid paper (design paper). One warp is shown between the vertical lines and one weft is shown between the horizontal lines, and the first point of the grid is the intersection of the warp yarns. The first glance is painted out to represent the fabric structure.

FIG. 1 shows that warp yarns and weft yarns intersect to form a plain weave fabric structure. The arrangement of the warp on the weft is called "floating". The arrangement of the warp under the weft is called "sinking". Plain weave tissue is made up of alternating floats and sinks. FIG. 2 is an organization chart of plain weave. The woven structure is represented by blacking out the floating portions in the eyes. FIG. 3 shows the minimum unit of the plain weave structure. A woven fabric is a repetition of this minimum unit, which is called a complete structure.

FIG. 4 shows a part of a section taken along the line AA ′ of FIG.
FIG. 3 shows how the weft yarn 1 of FIG. 3 is crossed with the warp yarns a and b. The mark x in FIG. 4 indicates the intersection of the warp and the weft. Here, the ratio of the portion where the warp yarns and the weft yarns intersect is defined as the crossing rate (%) and calculated by the following equation.

Ct = (i × 100) / (i + y) Ct: Crossing rate (%) i: Number of warps and wefts of perfect structure y: Number of warp yarns of perfect structure The smaller the numerical value of the crossing rate Ct, the more Since the weft yarn crossing rate is low, the number of yarns per unit width (yarn density) of the woven fabric can be increased.

In the case of plain weave, Ct = (2 × 100) /
(2 + 2) = 50 (%).

FIGS. 5 and 6 show the organizational diagram of the four-colored satin and how the warp and weft are interlaced.

The crossing rate Ct of the four sheets of red Ct = (2 × 100) /
(2 + 4) = 33.3 (%).

FIGS. 7 and 8 show the organizational diagram of a 2/2 twill weave and how the warp and weft yarns intersect.

The crossover rate of 2/2 twill weave Ct = (2 × 10
0) / (2 + 4) = 33.3 (%).

When a plurality of yarns are integrally structured, the crossing rate is reduced and the maximum weaving density can be increased.

FIG. 9 is a 4 × 4 basket organization. Each of the four warp and weft yarns together forms the same weave as plain weave. FIG. 10 shows the weft 1 of a 4 × 4 basket interlaced with the warp.

The crossing ratio Ct of a 4 × 4 basket = (2 × 1
00) / (2 + 8) = 20 (%).

In FIG. 11, two warp yarns and two weft yarns are integrally formed to form a four-colored satin similar to that shown in FIG. This will be referred to as “four sheets of red (2 × 2)”.
FIG. 12 shows the manner in which four weft (1 × 2) weft yarns 1 are interlaced with warp yarns.

The crossing rate of four pieces of red silk (2 × 2) is Ct = (2
(× 100) / (2 + 8) = 20%.

In FIG. 13, four warp and weft yarns are integrally formed to form a four-sheet satin similar to that shown in FIG. This will be referred to as “four sheets of red (4 × 4)”. FIG.
Indicates that four weft (1 × 4) weft yarns 1 are interlaced with the warp yarns.

The crossover rate of the same structure is Ct = (2 × 100)
/(2+16)=11.1 (%).

In FIG. 15, four warp and weft yarns are integrated to form a 2/2 twill weave as in FIG. This will be referred to as “2/2 twill weave (4 × 4)”.

FIG. 16 shows how 2/2 twill (4 × 4) weft yarns 1 are interlaced with warp yarns.

The crossover rate of the same structure is Ct = (2 × 100)
/(2+16)=11.1 (%).

As compared with the woven fabrics having the same woven density, the lower the crossing ratio (Ct), the lower the ratio of warp / weft crossing, and the smaller the ratio of warp / weft binding to each other, the better the resin impregnation.

The crossover rate (Ct) of the high-strength reinforcing fiber sheet of the present invention is desirably 10 to 30 (%). 30 (%)
When the ratio exceeds the above, the warp / weft interlacing ratio is high, and a high-density woven fabric cannot be obtained, and the resin impregnation property is poor. Crossing rate 10
If it is less than (%), the warp / weft crossing rate is extremely small, and thus the misalignment of the warp / weft tends to occur in the handling of the reinforcing fiber sheet, which is not practical as a fabric structure used in the present invention. .

The impregnating property of the resin is determined by actually impregnating the reinforcing fiber sheet with the resin by a method described later and observing the impregnation state of the resin. Alternatively, the determination can be made by measuring the air permeability. That is, the reinforcing fiber sheet having high air permeability is
Since there are many voids in the woven fabric, resin impregnation is also high.

As the reinforcing fiber sheet, JIS L-
1096 The air permeability by the 6.27A method is 5 (cm ³ /
cm ² · Sec) or more, but 6 (cm ³ /
cm ² · Sec) or more. 5 (cm ³ /
In the case of less than cm ² · Sec), since the space between the yarns is small, the impregnating property of the resin is poor, and a sufficient adhesive force cannot be obtained between the reinforcing surface and the reinforcing fiber sheet. In some cases, air bubbles remain between the fiber sheets for use and the reinforcing effect is reduced.

The reinforcing fiber sheet of the present invention is a bidirectional reinforcing fiber sheet having a good resin impregnation property and a proof stress of 35 tons / m or more. If it is less than this, the number of laminations is large and it is not efficient in reinforcing the floorboard of a road that requires a high proof stress.

The fineness of warp and weft is 1500 to 5000
(Dtex) is preferred. Below 1500 dtex,
The desired resin impregnating property cannot be obtained, and a high-yield woven fabric cannot be obtained. Yarns exceeding 5000 dtex may cause weft yarn cut errors or insufficient weft yarn gripping by the rapier even in looms such as rapier looms used when weaving high-weight fabrics with this kind of thick yarn. However, some of the fibers constituting the weft may be folded back during the insertion of the weft, causing a problem as a woven fabric.

The twist coefficient (K) is used as a numerical value representing the degree of twist regardless of the thickness of the yarn.

From the viewpoint of resin impregnation, it is desirable not to twist the warp yarn and the weft yarn. However, considering the weaving properties, it is better to add a little twist to the warp yarn during warping and weaving in the preparation step of the woven fabric. Less fuzz and good weaving. On the other hand, when twist is added to the yarn, the space between the fibers of the fibers constituting the yarn decreases, impairing the resin impregnating property, and impairing the resin impregnating property to the woven fabric. The fiber reinforced sheet of the present invention,
It is desirable that the degree of twist is small, but in consideration of the weaving property, the warp and weft have a twist coefficient K = 40 expressed by the following formula.
It is desirable to apply a twist of 00 or less, and K = 300 to
3000 is more preferred. However, if weaving is possible, the number of warp yarns may be zero. The number of weft threads is preferably K = 0 to 4000, more preferably K =
0 to 3000.

K = T (D) ^1/2 K: Twist coefficient T: Twist number (times / m) D: Fineness (dtex)

[0067]

EXAMPLES The present invention will be specifically described below with reference to examples. The properties of the reinforcing fiber sheet were evaluated by the following method. (1) Yield strength of fiber sheet A test piece was prepared according to the following method and was subjected to JIS K7073.
The measurement was carried out in accordance with the "Test method for carbon fiber reinforced plastic". The measured value was converted to the tensile strength of a fiber sheet having a width of 1 m, which was defined as the proof stress of the fiber sheet.

Grip Bond GB of Sumitomo Rubber Industries, Ltd.
-35 (epoxy resin), a main agent and a curing agent are mixed in accordance with the specification, a resin of the same weight as the basis weight of the fiber sheet is undercoated on the release film, and the fiber sheet is stuck thereon. After the resin sheet is well impregnated, a resin impregnated test piece is prepared by overcoating with 40% of the basis weight of the fiber sheet. After leaving the resin at room temperature for several days to confirm the curing of the resin, the resin-impregnated fiber sheet is taken out of the film. This is width 1
The test piece is cut into a test piece having a length of 2.5 mm and a length of 200 mm, and a tensile test is performed at a grip distance of 100 mm. (2) Resin impregnating property The main agent and the curing agent are mixed with Grip Bond GB-35 (epoxy resin) of Sumitomo Rubber Industries, Ltd. according to the specification, and the fiber sheet weight per unit area is 1.4 on the release film. Apply twice the weight of resin. A 20 × 20 cm fiber sheet is placed thereon, and is reciprocated three times under a load of 2 kg using a metal roller having a width of 10 cm, and then left. The resin seeps out from the lower side of the fiber sheet toward the surface, and the sheet surface becomes wet. After 5 minutes, the impregnation of the sheet surface with the resin is observed, and the determination is made as follows.

Good: Leaching of resin to the sheet surface is 80% or more of the sheet surface. Impossible: Leaching of resin to the sheet surface is 80% or less of the sheet surface. (3) Air permeability JIS L-1096 According to the 27A method.

Examples 1 to 3 Polyparaphenylene terephthalamide fiber manufactured by Toray DuPont (having a tensile strength of 20.3 cN / dtex,
Tensile modulus 500 cN / dtex, single fiber 2.1
3dtex, trade name; Kevlar) yarn 3160dte
A twist of 50 (times / m) was added to x to obtain a warp and a weft. The twist coefficient of this twisted yarn is K = 2810. A rapier loom was used to weave a 4 × 4 woven fabric basket, 4 satin (2 × 2) and 4 satin (4 × 4).

The air permeability of these fabrics is 7.0, respectively.
At 5.3, 10.3 (cm ³ / cm ² · Sec), the resin impregnating property was good, and it was a satisfactory two-way fiber sheet with high yield strength.

Comparative Examples 1 to 3 The yarns having the same specifications as in Example 1 were woven with a plain weave, a 2 × 2 basket, and a four-sheet satin weave at the maximum fabric density. The crossover rate of these fabric structures was 30% or more, the air permeability was as low as 0.7, 1.5, 1, 7 respectively, and the resin impregnation was poor.

Example 4 Using a yarn having the same specifications as in Example 1, a 2/2 twill weave (4 × 4) was woven at the maximum fabric density. The woven fabric cover factor was as high as 1417, and a fiber reinforced sheet with a high yield strength of 58 tons / m was obtained. The gas permeability was 10.5, and the resin impregnation property was also good.

Comparative Example 4 A 2/2 twill weave (5 × 5) was woven using a warp / weft yarn having the same specifications as in Example 4. A fiber sheet having a high yield strength of 60 tons / m with good resin impregnation was obtained. However, since the crossover rate is 9.1 (%) and the woven structure is loose, the woven fabric is laid up during handling, even though it is woven at the maximum woven density.
Since the misalignment of the weft occurs, it hinders the construction work, and causes uneven reinforcement. Therefore, it is not suitable as a resin-reinforced fiber sheet.

Example 5 Using the same yarn as in Example 1, only the twist coefficient was high, K = 56
20 (100 twists / m) warp / weft 4
× 4 baskets were woven at the maximum weave density. Although the air permeability was 9.0, which was good, the degree of twist of the warp / weft was high, so that the resin impregnation was not good.

Example 6 The tensile strength and the tensile modulus were the same as in Example 1.
Kevlar fiber yarn 15 having a single yarn fineness of 1.58 dtex
A twist of 70 (twice / m) was added to 80 dtex to obtain a warp and a weft. The twist coefficient of this twisted yarn is K = 27
82. The woven fabric was woven at a maximum weaving density of 4 satins (4 × 4). The resin impregnation property was good, and the yield strength was 40 tons / m.

Comparative Example An 8 × 8 basket was woven at the maximum weaving density with the yarn having the same specifications as in Example 5. The yield strength was 35 tons / m, which was a level that could be used as a fiber reinforced sheet, but the air permeability was 3.
At 73, the resin impregnating property was poor, and was unsuitable as a fiber reinforced sheet. In this case, it is considered that the resin impregnating property is improved by lowering the fabric density, but at the same time, the proof stress is also reduced, so that it becomes unsuitable as a fiber reinforced sheet.

Comparative Example 6 A total of 6320 d of the original yarns used in Example 1 was combined.
tex, 35.5 (twist / m) twist is added.
Weft. The twist coefficient at this time is K = 2822. Weaving of a fiber sheet having a proof strength of 70 tons / m was attempted using a 3 × 3 woven fabric basket.

However, since the weft yarn was thick, the cut of the stitch ear in rapier weaving was not normal, and the shape of the tuft was markedly irregular. Also, the rapier was unable to grip the entire thick weft yarn, some fibers were not gripped by the rapier, and a yarn crack occurred when the weft was inserted. Air permeability could not be measured.

The above results are shown in Tables 1 to 4.

[0081]

[Table 1]

[0082]

[Table 2]

[0083]

[Table 3]

[0084]

[Table 4]

[0085]

The high-strength bidirectional reinforcing fiber sheet of the present invention is a woven fabric using high-strength fibers for warp and weft, and has excellent resin impregnating properties.
It is useful for reinforcement of concrete structures such as buildings, and buildings such as lighthouses and chimneys with stones and bricks. .

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing that warp yarns and weft yarns intersect to form a plain weave fabric structure.

FIG. 2 is an organization chart of a plain weave.

FIG. 3 is a complete organization chart of a plain weave organization.

4 is a plain weave of FIG.
FIG. 2 is a schematic cross-sectional view of a woven fabric showing a state where it is intersected with a woven fabric.

FIG. 5 is a complete organization chart of a four-sheet satin.

FIG. 6 is a schematic cross-sectional view of a woven fabric showing a state in which the four satin weft yarns 1 of FIG. 5 are interlaced with warp yarns.

FIG. 7 is a complete organization diagram of a 2/2 twill weave.

FIG. 8 is a schematic cross-sectional view of a woven fabric showing a state in which the weft yarn 1 having a 2/2 twill weave structure shown in FIG. 7 is crossed with a warp yarn.

FIG. 9 is a complete organization chart of a 4 × 4 basket.

FIG. 10 is a schematic cross-sectional view of a woven fabric showing a state in which the weft yarns 1 of the 4 × 4 basket of FIG. 9 are interlaced with the warp yarns.

FIG. 11 is a complete organization chart of four-colored satin (2 × 2).

FIG. 12 is a schematic cross-sectional view of a woven fabric showing a state in which the weft 1 of the four-sheet satin (2 × 2) of FIG. 11 is crossed with the warp yarn.

FIG. 13 is a complete organization chart of four-colored satin (4 × 4).

FIG. 14 is a schematic cross-sectional view of a woven fabric showing a state in which the weft 1 of the four-sheet satin (4 × 4) of FIG. 13 is crossed with the warp yarn.

FIG. 15 is a complete organization diagram of a 2/2 twill weave (4 × 4).

FIG. 16: 2/2 twill (4 × 4) weft 1 of FIG.
FIG. 3 is a schematic cross-sectional view of a woven fabric showing a state where a warp yarn is interlaced.

[Explanation of symbols]

 1, 2, 3 · · · weft in organization chart a, b, c · · · warp in organization chart x · · · intersection of warp and weft

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2E164 AA05 CA01 CA17 CB01 4L048 AA25 AA48 AA51 AB11 AB12 AC09 BA01 BA02 CA01 CA11 CA15 DA30 DA41 EA00 EB00

Claims (5)

[Claims] 1. A fabric comprising a high-strength fiber having a tensile strength of 16 cN / dtex or more, a fabric cover factor (Cf) represented by the following formula (a) is 800 to 1500, and a crossing represented by the following formula (b): Rate (Ct) is 10 to 30
(%) And the air permeability is 5 to 20 (cm ³ / cm ^2.
Sec), wherein the proof stress in the vertical direction and the horizontal direction is at least 35 (ton / m), respectively. Cf = (Dw) ^1/2 × Nw + (Df) ^1/2 × Nf --- (-) (a) Cf: Fabric cover factor Dw: Warp fineness (dtex) Df: Weft fineness (dtex) Nw: Warp yarn density (this / F) Nf: weft density (lines / cm) Ct = (i x 100) / (i + y)--------------------------------------------------------- Weft crossing number y: Number of warp yarns in perfect structure 2. The reinforcing fiber sheet according to claim 1, wherein the warp and the weft represented by the following formula (c) have a twist coefficient of 4000 or less. K = T (D) ^1/2 ---------------- (c) K; Twisting coefficient T: Twist number (times / m) D: Fineness (dtex) 3. A warp yarn and a weft yarn each having a fineness of 15
The reinforcing fiber sheet according to claim 1, wherein the number of the reinforcing fiber sheet is from 00 to 5000 (dtex). 4. The reinforcing fiber sheet according to claim 1, wherein the high-strength fiber is a para-aramid fiber. 5. The para-aramid fiber is polyparaphenylene terephthalamide.
The reinforcing fiber sheet according to any one of the above.