JP2002054219A - Concrete side-ditch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concrete side-ditch having the long service life by keeping longtime use without rusting a reinforcing material. SOLUTION: This concrete side-ditch is characterized by reinforcing concrete with a fiber reinforced material composed of at least continuous reinforcing fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gutter made of reinforced fiber reinforced concrete.

[0002]

2. Description of the Related Art Concrete gutters are frequently used as irrigation canals and drainage channels. Since these gutters are weak only with concrete, reinforcing bars are usually used as reinforcement and embedded in concrete. ing. Normally, the cross-sectional shape of the gutter is U-shaped, and the opening of the gutter is exposed to the atmosphere, and the others are buried in soil.
Water and drainage exist inside the gutters, and water contained in the soil also exists outside the gutters, which are used under severe environmental conditions. In other words, when the water penetrates into the reinforcing steel of the gutter, the reinforcing steel rusts and the life of the gutter is shortened. Therefore, the thickness of concrete is increased, and a sufficient cover of 3 cm or more is provided to prevent water from penetrating into the reinforcing steel. Have been. Although depending on the size of the gutter, the reinforcing bar is often located at a position equidistant from the inner side and the outer side, that is, substantially at the center of the side groove thickness.

When the cross section of a concrete pipe is a closed circular shape like an earthen pipe, the load is distributed to the rebar and the deformation is uniform, but when the cross section is an open shape such as a U-shape, the corner of the gutter is particularly used. Large deformation occurs locally in the part.

That is, since concrete has a low tensile strength, a truck or the like for carrying heavy objects passes near the outside of the gutter, or the soil freezes and expands in a cold region or the like, and the side surface of the gutter is bent inward. When a large load is applied,
The corners of the concrete outside the gutter, particularly the corners, are greatly deformed and cracks are generated, and the water contained in the soil and the water generated by melting the frozen soil penetrates from the cracks, causing a problem that the reinforcing steel rusts.

[0005] The rebar has a tensile strain of 0.1 to 0.2.
% Yield, the rebar yields when a large load is applied, and the U-shape will not recover to its original state, so not only will the resistance of the water channel increase or the landscape will be damaged, In cold regions, the water generated by melting the frozen soil fills the gap between the soil and the gutter, and when this water freezes, the expansion of the frozen soil pushes the gutter further inward, further accumulating strain in the reinforcing steel. It gets bigger. And when these freezing and thawing are repeated,
Eventually, there is a problem that the reinforcing bar is broken and the gutter is crushed. Especially in cold regions, gutters break down in winter and
It will not last for years or it will be necessary to lay gutters every year, and the annual construction cost will be enormous.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to pay attention to such a current situation, and to endure long-term use without reinforcing the rust of the reinforcing material and increasing the proportional limit strain of the reinforcing material. It is to provide a concrete gutter having a long life.

[0007]

In order to achieve the above object, the present invention has the following arrangement. (1) A concrete gutter, wherein the concrete is reinforced with a fiber reinforcing material composed of at least continuous reinforcing fibers.

(2) The concrete gutter according to (1), wherein the fiber reinforcing material is a fiber-reinforced plastic material.

(3) The fiber reinforcing material according to (2), wherein the fiber reinforcing material is a fiber-reinforced plastic material comprising a unidirectional sheet in which a number of reinforcing fiber yarns are arranged in one direction. Concrete gutter.

(4) The concrete gutter according to (3), wherein the one-way sheet is a one-way fabric.

(5) The fiber reinforcing material is a fiber reinforced plastic material comprising a bidirectional sheet in which a large number of reinforcing fiber yarns are arranged in two directions of a length direction and a width direction. The concrete gutter according to (2).

(6) The concrete gutter according to the above (5), wherein the fiber reinforcing material has a mesh shape.

(7) The concrete gutter according to any one of (2) to (6), wherein the fiber reinforced plastic material is embedded in concrete.

(8) The fiber-reinforced plastic material is adhered to the surface of the side groove.
The concrete gutter according to any of (6).

(9) The above (2) to (2), wherein the reinforcing fibers are arranged at least in the circumferential direction of the U-shaped tube.
(8) The concrete gutter according to any of (8).

(10) The reinforcing fiber has a tensile modulus of 50.
The concrete gutter according to any one of (2) to (9), wherein the gutter is GPa or more and the proportional limit strain is 0.5% or more.

(11) The concrete gutter according to any one of (1) to (10), wherein the reinforcing fibers are carbon fibers.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the embodiments shown in the drawings. FIG. 1 is a partially broken perspective view showing an example of the concrete U-shaped groove of the present invention.

The concrete gutter 1 shown in FIG. 1 has a U-shaped cross-section, and is entirely composed of ordinary concrete 2 and a number of reinforcing bars extending in the length direction of the gutter substantially in the center of the thickness of the concrete. 3 are arranged to reinforce the longitudinal direction of the groove, and continuous reinforcing fibers 4 are arranged in the circumferential direction B of the side groove, and the continuous reinforcing fiber 4 is fixed to the reinforcing bar at the upper part 8 of the side surface 5 of the side groove. , Extending from the side surface 5 to the bottom surface 6 and the upper portion of the opposite side surface 7 to reinforce the circumferential direction of the side groove.

The reinforcing fiber used in the present invention has a linear relationship between stress and strain until the reinforcing material yields even under a severe environment in which melting and freezing are repeated. It is preferably at least 0.5%. If the proportional limit strain is less than 0.5%, a large load is repeatedly applied to the side surface of the gutter inwardly due to freezing and thawing of the soil as in the case of the rebar, and cracks are formed in the concrete corner portion 9 of the gutter. Even if it occurs and is unloaded, the side surface is bent inward and cannot be restored to its original shape, or it is easily broken and the life is shortened, which is not preferable.
When the proportional limit strain is 0.5% or more, it withstands repeated fatigue due to a large load, and even if cracks occur in the corner portion 9, the shape of the side groove is restored to the original shape when unloaded, Life can be extended.

The term "proportional strain limit" as used in the present invention means a strain-load diagram of tensile strength in the direction of the reinforcing fiber axis of a fiber reinforced plastic laminated so that the fiber axis of the fiber reinforcing material is in the same direction.
The strain at which the load is reduced by 10% is determined from the extension of the initial rising straight line by ISK 7073, and is the average value of five measurements. From the viewpoint of further enhancing the reinforcing effect of the reinforcing fiber and extending the life of the gutter, the proportional limit is 1.
More preferably, it is 0% or more.

The tensile modulus of the reinforcing fibers is preferably 50 GPa or more from the viewpoint of enhancing the reinforcing effect of the concrete. The tensile modulus of concrete is usually 2
Since it is about 0 GPa, the tensile modulus of the reinforcing fiber is 50
GPa or more is preferable because the reinforcing fibers can carry a large amount of tensile stress applied to the concrete, and the reinforcing effect of the reinforcing fibers on the concrete increases. More preferably, it is 200 GPa or more.

In the present invention, the tensile modulus is JIS R 7
Item (4) in the test of the resin-impregnated strand in Section 6.6.2 of No. 601;
This is the average of the measured values.

Examples of such reinforcing fibers include glass fibers, polyaramid fibers, carbon fibers, ultra-high-molecular-weight polyethene fibers having high strength and high elastic modulus, and polyparaphenylenebenzobisoxazole fibers. It is preferably used because it has excellent water resistance and chemical resistance. Furthermore, it is preferable to use a carbon fiber having a proportional limit strain of 1.5% or more and a tensile modulus of 230 GPa or more, because the life is prolonged and the effect of reinforcing concrete is increased.

The continuous reinforcing fiber is 3,000 to 80,000.
A single strand of decitex may be used alone, but the workability of attaching these reinforcing fibers and the gap between the reinforcing fibers and the reinforcing fibers are increased, and several strands are combined so that concrete can sufficiently enter the gaps. Twisted ply-twisted yarn, or a combination of several yarns, and the periphery thereof may be covered with another auxiliary yarn by covering means or string-making means,
Further, a thin woven fabric may be provided with an interval therebetween. The purpose of the present invention can be achieved even if the continuous reinforcing fiber shown in FIG. 1 is not impregnated and adhered to the matrix resin as the fiber reinforced plastics. It is more preferable because the strain limit and the tensile modulus can be fully exhibited, and a sufficient reinforcing effect can be obtained with a small amount of reinforcing fiber.

FIG. 2 is a partially cutaway perspective view for explaining another embodiment of the present invention. Similar to the embodiment shown in FIG. 1, the concrete gutter 1 is provided with a number of reinforcing bars 3 extending in the length direction of the gutter to reinforce the length direction of the groove, and the side surfaces of the gutter,
A fiber-reinforced plastic comprising a sheet 11 in which reinforcing fiber yarns 10 are arranged in one direction is bonded to the outside of the bottom surface. The fiber-reinforced plastic is laminated so that the orientation of the reinforcing fibers is in the circumferential direction of the side groove, and extends from the side surface 5 to the bottom surface 6 and the upper portion of the opposite side surface 7 to reinforce the circumferential direction of the side groove.

In particular, when a load is applied such that the side surface of the gutter is bent inward, concrete has a lower tensile strength than the compressive strength, so that cracks are generated on the outside of the corner where the tensile stress acts. This portion is reinforced with fiber reinforced plastic, and since reinforcing fibers are arranged in the circumferential direction, the portion is sufficiently reinforced even when a load for bending inward is applied, and a strong side groove is formed.

The reinforcing material may be located inside the U-shaped groove, but the reinforcing material is damaged by soil or stone flowing in the groove,
It is preferable to place the reinforcing member outside the groove because the effect of suppressing cracks increases without damage.

The unidirectional sheet used in the present invention is a unidirectional woven fabric in which reinforcing fibers are arranged in one direction and auxiliary yarns are arranged in the other direction. Preferred but not limited to this
Reinforcement fibers are arranged in one direction, and thin glass fiber yarn,
It may be a unidirectional sheet formed by bonding a mesh-like material or a non-woven fabric made of polyaramid fiber yarn, polyethylene yarn, or the like, or a unidirectional prepreg pre-impregnated with a matrix resin.

The basis weight of the reinforcing fibers of the unidirectional sheet is 150
g / m ² ~1,000g / m ² about is good. The basis weight is 15
If it is less than 0 g / m ^2, it is necessary to increase the number of laminated layers in order to obtain a predetermined reinforcing effect, and the operation becomes complicated, which is not preferable. On the other hand, if it exceeds 1,000 g / m ² , the impregnation of the resin into the sheet is alienated, which is not preferable. The basis weight is 15
Impregnation of the in the range of 0g / m ² ~1,000g / m ² resin is not particularly problematic, be preferably so that live in the lamination of one from the viewpoint of reinforcement design, selected within the range of the mass per unit area preferable. More preferably, 250 g / m ² to 5
00 g / m ² .

FIG. 3 is a partially cutaway perspective view for explaining another embodiment of the present invention. FIG. 3 shows an example in which the side grooves are reinforced with a fiber reinforced plastic composed of a bidirectional sheet 12 in which reinforcing fiber yarns are arranged in two directions of the warp direction and the weft direction. The longitudinal direction of the side groove is reinforced by arranging in the length direction, and the reinforcing fiber yarns 14 in other directions are arranged in the circumferential direction of the groove to reinforce the circumferential direction of the side groove.

Since it is not necessary to use a reinforcing bar for such a side groove, the reinforcing member does not deteriorate due to rust, and there is no need to cover concrete with a constant thickness as a measure against water penetration. Therefore, it is preferably used because a light side groove is obtained and the laying operation is simplified.

The bidirectional sheet used in the present invention includes:
Ordinary bidirectional woven fabric obtained by weaving operation, reinforcing fiber yarns are arranged straight in the warp direction and weft direction, and the bidirectional fabric formed by knitting operation or stitching operation with thin auxiliary yarn, or these Prepreg and the like.

The basis weight of the reinforcing fibers of the bidirectional sheet is 200
g / m^Two~ 1,000g / m^TwoGood degree. 200g /
m^TwoIf it is less than this, the drapability increases, and when laminating,
It is difficult to accurately perform fiber orientation in a predetermined direction
In order to obtain the required reinforcing effect, it is necessary to increase the number of layers
This is not preferable because the operation is complicated. Also eyes
With 1,000g / m^TwoExceeds the limit of resin in the sheet
The immersion property is alienated, which is not preferable. The basis weight is 200 g / m^Two~
1,000 g / m^TwoIf it is in the range, the impregnating property of the resin is
There is no problem, and it is preferable that one layer
Therefore, it is only necessary to make a selection within the range of the basis weight. Than
Preferably 250 g / m^Two~ 500g / m ^TwoIt is.

Further, the reinforcement in the length direction and the circumferential direction of the side grooves is not necessarily limited to the two-way sheet. You may make it become a direction.

Such a side groove is preferable because it can be easily manufactured, for example, as follows. First,
Create a concrete gutter, apply a primer if necessary, then apply a cold-curing thermosetting resin on the entire surface of the surface, which is a matrix of fiber-reinforced plastic, and reinforce the fiber before the resin cures Laminate the material, further apply a room temperature curing type thermosetting resin on the entire surface,
The resin is impregnated and defoamed with a roller or a spatula, and when left at room temperature, the resin hardens to become a fiber reinforced plastic, and the fiber reinforced plastic can be bonded to concrete.

The resin used in the present invention is preferably a thermosetting resin of a room temperature curing type from the viewpoint of workability, and examples thereof include an epoxy resin, an unsaturated polyester resin, a vinyl ester resin and a phenol resin. Among them, epoxy resin is preferably used because the adhesion between concrete and fiber-reinforced plastic becomes strong.

FIG. 4 is a partially cutaway perspective view for explaining another embodiment of the present invention. FIG. 4 shows an example in which the gutters are reinforced by a mesh-like fiber reinforced plastic 15 in which reinforcing fiber yarns are arranged in two directions perpendicular to each other, and the mesh-like fiber reinforced plastic 15 is substantially at the center in the thickness direction of the concrete. The reinforcing fiber yarns 16 in one direction are arranged in the length direction of the groove to reinforce the length direction of the side groove, and the reinforcing fiber yarns 17 in the other direction are arranged from the side surface 5 to the bottom surface 6, the opposite side surface. 7 are arranged so as to extend to the upper part of the groove 7 to reinforce the circumferential direction of the side groove. When laying the gutter on the ground, soil or gravel is put between the ground and the gutter to fill the gap and fix the gutter to the ground.In this embodiment, the reinforcing material is embedded in the concrete. The groove is not damaged, and is not damaged during transportation, so that the groove becomes highly reliable.

The basis weight of the reinforcing fiber of the mesh is 100 g / m.
It is preferably about ^{2 to} 700 g / m ² . If the basis weight is less than 100 g / m ^2, it is necessary to increase the number of laminations in order to obtain a predetermined reinforcing effect. On the other hand, if it exceeds 700 g / m ² , the size of the mesh becomes small, and the flow of concrete is alienated when forming the gutter, which is not preferable. The basis weight is 10
When in the range of 0g / m ² ~1,000g / m ² impregnated resin is not particularly a problem, so that preferably requires a stack of one from the viewpoint of reinforcement designs may be selected within the range of this weight per unit area . More preferably, the basis weight is 200 g / m ² to 80.
0 g / m ² .

Although the size of the mesh depends on the size of the gravel mixed in the concrete, the length of one side is 2 mm.
cm or more, more preferably 5c
m or more, and preferably 7 cm or less. When the length of one side of the mesh is less than 2 cm, when making the gutter, gravel is clogged in the mesh, concrete flow is alienated, and not only concrete property is not obtained, but also the place where concrete does not flow It is not preferable because it can result in defective products. On the other hand, if it exceeds 7 cm, the portion of the concrete where no reinforcing material is present becomes large, resulting in a weak gutter, which is not preferable.

Such a side groove can be manufactured, for example, as follows. The mesh-like fiber reinforced plastic used in the present invention is formed by arranging a mesh woven fabric or a reinforcing fiber yarn obtained by a weaving operation straight in a warp direction and a weft direction, and forming the fabric by knitting operation or stitch operation with a thin auxiliary yarn. A prepreg in which a thermosetting resin is impregnated in a prepared mesh is made, and the prepreg is made to conform to a shape located at a substantially central portion of a side groove, and heated to cure the resin, thereby forming a U-shaped mesh-shaped fiber reinforced plastic. Make it.

The mesh-shaped fiber reinforced plastic is set on the concrete form so as to be located at substantially the center of the concrete thickness, and concrete is poured into the concrete form and solidified to easily manufacture the gutter. be able to.

In the above description, the mesh-like fiber reinforced plastic is located substantially at the center of the thickness of the concrete. However, the present invention is not limited to this. For example, the mesh-like fiber reinforced plastic is located outside the center. It may be a side groove formed.

In the above description, the side groove has been described as having a straight shape in the length direction. However, the side groove may be bent in the length direction.

[0045]

As is apparent from the above description, the concrete gutter of the present invention is used to reinforce concrete by using a fiber reinforced plastic obtained by impregnating a continuous reinforcing fiber yarn or a sheet of continuous reinforcing fiber yarn with a resin. Because of this, the reinforcing material does not rust, can withstand many years of use, and has a long life.

Further, since the concrete gutter of the present invention uses a reinforcing material having a large proportional limit strain as compared with the conventional reinforcing bar, even in a severe environment in which melting and freezing are repeated, a large side wall is bent inward. Even if the load is repeatedly applied and the concrete corner of the gutter cracks,
When unloaded, the side surface is bent inward to recover the original shape, and the life of the gutter can be extended.

Further, since the reinforcing fiber having a large tensile modulus is used, the reinforcing fiber can bear a large amount of tensile stress applied to the concrete, and the effect of reinforcing the concrete by the reinforcing fiber is increased.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing an example of a concrete gutter of the present invention (a reinforcing material is a reinforcing fiber).

FIG. 2 is a partially broken perspective view showing another example of the concrete gutter of the present invention (fiber-reinforced plastic in which a reinforcing material is a one-way sheet).

FIG. 3 is a partially broken perspective view showing still another example of the concrete gutter of the present invention (a fiber-reinforced plastic in which a reinforcing material is a two-way sheet).

FIG. 4 is a partially broken perspective view showing still another example of the concrete gutter of the present invention (the reinforcing material is a mesh-like fiber reinforced plastic).

[Explanation of symbols]

 1: Concrete gutter 2: Concrete 3: Reinforcement 4: Continuous reinforcing fiber 5: Side surface of gutter 6: Bottom surface of gutter 7: Opposite side of gutter 8: Reinforcing bar 9: Corner of gutter 10: Reinforcing fiber thread 11 : Unidirectional sheet 12: Bidirectional sheet 13: Unidirectional reinforcing fiber yarn 14: Other direction reinforcing fiber yarn 15: Mesh fiber reinforced plastic 16: Unidirectional reinforcing fiber yarn 17: Other direction Reinforced fiber yarn

Claims (11)

[Claims] 1. A concrete gutter, wherein the concrete is reinforced with a fiber reinforcement made of at least continuous reinforcing fibers. 2. A concrete gutter according to claim 1, wherein said fiber reinforcement is a fiber reinforced plastic material. 3. A concrete made of concrete according to claim 2, wherein said fiber reinforcing material is a fiber reinforced plastic material comprising a unidirectional sheet in which a number of reinforcing fiber yarns are arranged in one direction. Gutter. 4. The concrete gutter according to claim 3, wherein said one-way sheet is a one-way fabric. 5. A fiber reinforced plastic material comprising a bidirectional sheet in which a number of reinforcing fiber yarns are arranged in two directions of a length direction and a width direction. Item 3. A concrete gutter according to item 2. 6. A concrete gutter according to claim 5, wherein said fiber reinforcement is mesh-shaped. 7. The fiber reinforced plastic material is embedded in concrete.
6. The concrete gutter according to any one of 6. 8. The concrete gutter according to claim 2, wherein said fiber reinforced plastic material is bonded to a surface of the gutter. 9. The concrete gutter according to claim 1, wherein the reinforcing fibers are arranged at least in a circumferential direction of the U-shaped pipe. 10. The reinforcing fiber has a tensile modulus of 50 GPa.
The concrete gutter according to any one of claims 1 to 9, wherein the proportional strain is 0.5% or more. 11. The concrete gutter according to claim 1, wherein said reinforcing fibers are carbon fibers.