JP2001262708A - Frp concrete composite structure using frp lamination panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite structure member capable of reducing life cycle cost because of no need for a special corrosion-protective means, dispensing with reinforcement for securing rigidity to restrict cost, reducing friction loss of prestress, and reducing necessary quantity of PC steel members. SOLUTION: In a structure member 10 having an I-, T- or box-shaped cross section, a web comprising an FRP lamination panel 13 is provided between upper and lower flanges 11, 12 comprising concrete, a PC steel member 15 is extended in an axial direction of the member 10 to be inserted into the lower flange concrete or into a deviator provided in the lower flange concrete, and the PC steel member 15 is tensed to introduce prestress.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite structure of FRP and reinforced concrete, and more particularly to a structure applicable mainly to construction of a PC bridge and a PC building.

[0002]

2. Description of the Related Art After the collapse of the bubble economy, there has been an increasing demand for cost reduction of construction works, especially public works. Therefore, the ultimate goal of construction technology development is
It is not an exaggeration to say that construction costs are being reduced. Prestressed concrete bridge with box section (P
In response to this demand, a PC bridge 90 having a box section having a composite structure of a corrugated steel sheet and reinforced concrete shown in FIG. That is, in the PC bridge 90, the upper floor slab 91 and the lower floor slab 93 are formed of reinforced concrete, and a web 92 made of a corrugated steel sheet is provided between the upper slab 91 and the lower floor slab 93.
It is constructed by inserting a steel material, and aims to reduce the cost of construction work by not forming the web 92 with reinforced concrete as in the related art.

[0003]

However, many problems have been pointed out as described below in the conventional PC bridge 90 having the composite structure. When using a steel sheet web instead of the conventional web made of reinforced concrete, it is necessary to use pre-stress by reducing the axial rigidity by using a corrugated one because the steel sheet has a high elastic modulus, As a result, the amount of steel used increases, and the processing cost also increases, which does not necessarily lead to cost reduction. In many cases, this causes an increase in construction cost. In the case of steel sheet webs, painting must be performed regularly to prevent rust, which not only increases the life cycle cost, but also causes rainwater to collect at the joint between the steel sheet web and the lower flange concrete, and the steel sheet Special anticorrosion measures are required because the web is susceptible to corrosion. If the web is formed of corrugated steel sheet, it is necessary to weld and reinforce the steel sheet or steel bar at the upper and lower ends of the corrugated steel sheet to secure rigidity during erection. Also has the disadvantage of increasing. Since the corrugated steel sheet is heavy and bulky, there is a drawback that handling during transportation and erection is poor, and the construction cost is increased.

[0004] Accordingly, an object of the present invention is to provide a composite structural member capable of reducing the amount of use of PC steel material because frictional loss is small and prestress can be efficiently introduced. Another object of the present invention is to provide a composite structural member that can reduce the life cycle cost without requiring special anticorrosion means. Another object of the present invention is to provide a composite structural member which does not require special reinforcement for the erection member to secure rigidity at the time of erection and can reduce labor and material cost.

[0005]

According to the present invention, in a structural member having a cross section of an I-shape, a T-shape or a box-shape, FRP is provided between upper and lower flanges made of concrete.
A web composed of laminated panels is provided, and the PC steel is extended in the axial direction of the member by penetrating through the concrete of the lower flange or through the divider provided on the lower flange, and the PC steel is tensioned to prestress. The present invention provides a FRP concrete composite structural member characterized by introducing:

In the present invention, it is preferable to use the FRP laminated panel which is laminated so that the fiber directions of the respective layers intersect. Further, as the FRP laminated panel, a panel provided with an ultraviolet blocking layer on the uppermost layer of the surface irradiated with ultraviolet rays, or a panel provided with a buckling prevention member extending in a vertical direction on an outer surface at a predetermined interval is used. It is preferable to use one having both the ultraviolet blocking layer and the buckling preventing member.

Here, the surface irradiated with the ultraviolet rays is a surface directed outward when the cross section of the structural member is box-shaped, and is a double-sided surface when the cross section is I-shaped or T-shaped. is there. Further, the ultraviolet ray blocking layer itself is hardly deteriorated by the irradiation of ultraviolet rays, and is preferably made of a material that protects the lower layer FRP from ultraviolet rays. There are silicone-based and fluorine-based paints or films. By providing such an ultraviolet ray blocking layer, the weather resistance of the FRP laminated panel is increased, and the durability of the structural member is improved.

Although the buckling preventing member is not particularly limited,
The FRP laminated material can be fixed to the FRP laminated panel by means such as an adhesive.

In the present invention, the FRP laminated panel may be composed of a reinforcing fiber component and a thermosetting resin component. The reinforcing fiber component is one-way roving,
It is used as a roving cloth or a cloth (woven cloth) such as plain weave, satin weave, twill weave, etc. arranged in multiple directions, and a plurality of these single types are laminated to form an FRP laminated panel, or a plurality of types are laminated. FRP laminated panels can be formed.

The reinforcing fiber component constituting the FRP laminated panel preferably has an elastic modulus lower than that of the PC steel material. Examples of the reinforcing fiber component include carbon fiber, aramid fiber, polyester fiber, polyamide fiber, vinylon fiber and high-strength polyethylene fiber. It is any fiber selected from inorganic fibers such as organic fibers and glass fibers, or used as a hybrid type combining a plurality of the above fibers.

The FRP laminated panel can be formed by impregnating a reinforced fiber component with a liquid thermosetting resin and curing the thermosetting resin. As the liquid thermosetting resin, for example, an unsaturated polyester resin,
Vinyl ester resins, epoxy resins, phenolic resins and acrylic syrup resins can be used. Any of these thermosetting resins can be cured at normal temperature or under heating, and all of them are radical polymerization type resins except for the epoxy resin and the phenol resin. Therefore, these can be used in combination.

Further, the present invention aims to use the FRP laminated panel as a structural member for a long period of time, so that durability is extremely important. Further, the FRP laminated panel has various mechanical properties, water resistance, heat resistance, and the like. Chemical resistance, weather resistance, and the like are required, and it is necessary to have these characteristics in a well-balanced manner. As a matrix resin component for obtaining such an FRP laminated panel, a thermosetting resin is excellent,
Among them, an isophthalic unsaturated polyester resin and an acrylic syrup resin are particularly preferred.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1A is a side view of a first embodiment of the present invention, FIG. 1B is a sectional view thereof, and FIGS. 2A to 2C are more detailed sectional views of FIG. is there. In FIG. 1 and FIG.
A plurality of FRP laminated panels 13 are continuously connected between an upper flange 11 and a lower flange 12 made of reinforced concrete to form a web, and a diaphragm 1 made of reinforced concrete is formed at a place where the FRP laminated panels 13 are attached to each other.
The upper flange 1 is formed by the diaphragm 14.
1 and the lower flange 12 are connected, a PC steel material 15 is inserted into the lower flange 11 to extend in the axial direction of the T-shaped structural member 10, and the PC steel material 15 is tensioned to introduce prestress. .

The diaphragm 14 is a reinforcing member provided for preventing buckling, and is preferably provided at all locations where the FRP laminated panels 13 are attached to each other as described above. If sufficient buckling resistance is obtained, the diaphragm 14
May be provided only in a part of the above-mentioned portion. This is the same in a second embodiment described later.

The FRP laminated panel 13 is formed by laminating a plurality of sheets made of reinforcing fibers such that the fiber directions of the respective layers are orthogonal to each other. They are arranged in the same direction and formed using a matrix agent such as an unsaturated polyester resin containing isophthalic acid. Further, it is preferable to form an ultraviolet blocking layer on one or both sides of the FRP laminated panel 13 exposed to sunlight (ultraviolet rays) with a material for preventing transmission of ultraviolet rays on the surface thereof. The performance and durability can be improved.

The FRP laminated panel 13 is shown in FIG.
As shown in the figure, the holes 13a, 1
3b are formed, and cutouts 13c are formed on the left and right sides. These holes 13a and 13b are used for fixing to a reinforced concrete portion through a reinforcing bar when constructing a structural member. These holes 13a and 13b are formed to be large enough to allow the concrete aggregate to pass through even when the reinforcing bar is inserted. For example, the holes 13a and 13b are formed to have a size of about 25 to 80 mm according to the size of the aggregate and the thickness of the FRP laminated panel 13. Can be. Thereby, the fixing between the FRP laminated panel 13 and the concrete portion can be strengthened.

As other FRP laminated panels, the panels shown in FIGS. 5B and 6A and 6B can be used. FIG. 5B is a front view of the FRP laminated panel 33, in which holes 33a for inserting a reinforcing bar are provided only on upper and lower sides, and holes and notches are not provided on left and right sides. 6A and 6B show the FRP laminated panel 43.
FIG. 3 is a front view and a plan view of a stiffener 43c having holes 43a and 43b for inserting reinforcing bars on the upper, lower, left, and right sides.
Are provided at predetermined intervals so as to extend in the vertical direction on one side or both sides of the panel, and the stiffener 43c is formed of an FRP laminated material. The stiffener 43c is provided as a buckling prevention member, and is for preventing buckling of the web together with the reinforced concrete diaphragm. The FRP shown in FIG.
In the laminated panel 43, the FRP is provided with holes for reinforcing bars only on the upper and lower sides without providing holes for reinforcing bars on the left and right sides.
Laminated panels can also be used for the structural member of the present invention.

Next, the upper and lower flanges 11, 12 will be described. The upper and lower flanges 11 and 12 extend in the axial direction of the structural member, respectively.
b and the axial reinforcing bars 11d and 12d are arranged, and the upper and lower sides of the FRP laminated panel 13 are arranged between these reinforcing bars. 11c and 12c are inserted and hardened with concrete 11a and 12a. A PC steel material 15 is inserted through the center of the lower flange 12 in the axial direction of the material, and the PC steel material 15 is fixed by the fixing members by the diaphragms 14 at both ends.

In each diaphragm 14, a shear reinforcing bar and an assembly bar are arranged.
As shown in (b), the FRP laminated panel 13 is inserted into the holes 13b on the left and right sides and arranged to provide reinforcement.
a.

Next, the operation of the T-shaped structural member 10 shown in FIGS. 1 and 2 will be described. In the T-shaped structural member 10, a web is formed from a plurality of FRP laminated panels 13. Since the FRP laminated panel is much thinner than a concrete web, the bending stress generated by the girder's own weight and live load is reduced by F.
It is not necessary to put a load on the web composed of the RP laminated panel 13, and since the elastic modulus is lower than that of the steel plate, if a prestress is introduced in the axial direction of the concrete portion of the upper and lower flanges, the concrete portion can be easily formed in the axial direction. Due to the compression deformation, the prestress can be effectively introduced into the T-shaped structural member 10 with little friction loss.

Next, FIG. 3 is a perspective view of a second embodiment of the present invention, FIG. 4 (a) is a cross-sectional view of FIG. 3 partially cut away, and FIG. It is sectional drawing in IVb-IVb of FIG. In FIG. 3, the box-shaped structural member 2
0 is the upper slab 21 and the lower slab 2 made of reinforced concrete
2, the FRP laminated panels 43 are continuously arranged in two rows at a predetermined interval to form a web, and a diaphragm 24 made of reinforced concrete is formed at a place where the FRP laminated panels 43 are attached to each other. Above is the divider 2
6, a PC steel material 25 is inserted into the divider 26 to extend in the axial direction of the box-shaped structural member 20, and the PC steel material 25 is tensioned to introduce prestress.

Here, similarly to the first embodiment, the FRP laminated panel 43 has upper and lower floor slabs 21, 22 on the upper, lower, left and right sides.
It is buried and fixed inside, and the fixed part is
(A) and (b) are shown in sectional views. That is, while the rebars 21c and 22c are inserted into the holes 43a on the upper and lower sides, respectively, the rebars 24e are inserted into the holes 43b on the right and left sides, respectively.
By placing concrete so as to bury the upper, lower, left and right sides of the laminated panel 43, the upper and lower floor slabs 21, 22 and the diaphragm 24 were formed. The FRP laminated panel 43
The one having the stiffener 43c provided on only one side was used, and the surface on which the stiffener 43c was provided was arranged facing inward. Further, the reinforcing bars 21c, 22
If c can fix the FRP laminated panel 43 in concrete, its shape is not limited to the one shown in the figure.
Other shapes can also be used. In addition, about the structure similar to 1st Example in 2nd Example, further description is abbreviate | omitted below. Further, the function of the above-mentioned T-shaped structural member 10 can be similarly obtained in the box-shaped structural member 20.

[0023]

According to the FRP concrete composite structural member of the present invention, since the elastic modulus of the FRP laminated panel is low, it is not necessary to use a corrugated panel as in the case of the conventional composite structural member, and it is effective for the concrete section. In addition, it is possible to introduce a pre-stress into the steel plate, and it is possible to save the amount of PC steel used. Further, in the FRP concrete composite structural member of the present invention, since the FRP laminated panel provided with the ultraviolet ray blocking layer on the uppermost layer of the surface irradiated with ultraviolet rays is used as the web, complicated maintenance work such as painting can be omitted. Further, in the present invention, the FRP laminated panel is lighter than the corrugated steel sheet, so that it is easy to handle at the time of transportation or erection, and is laminated such that the fiber direction of each layer intersects with each other. Good shear strength can be obtained for a web formed of panels.

[Brief description of the drawings]

FIG. 1 (a) is a side view of a first embodiment of the present invention,
(B) is sectional drawing in Ib-Ib of (a).

2A is a cross-sectional view taken along IIa-IIa in FIG. 1A, FIG. 2B is an enlarged cross-sectional view showing a joint between the FRP laminated panel and a lower flange, and FIG. ) Of (b)
It is sectional drawing in IIc-IIc.

FIG. 3 is a perspective view of a second embodiment of the present invention.

4A is a cross-sectional view of FIG. 3 partially cut away, and FIG. 4B is a cross-sectional view taken along line IVb-IVb of FIG.

FIGS. 5A and 5B are front views of different FRP laminated panels.

6A is a front view of an FRP laminated panel different from FIG. 5, and FIG. 6B is a plan view of FIG.

FIG. 7 is a perspective view partially showing a conventional PC bridge having a box section.

[Explanation of symbols]

 Reference Signs List 10 T-shaped structural member 11 Upper flange 12 Lower flange 13, 33, 43 FRP laminated panel 15, 25 PC steel 20 Box-shaped structural member 21 Upper floor plate (upper flange) 22 Lower floor plate (lower flange) 33 FRP laminated panel 43c Stiffener (Buckling prevention member)

Continuing from the front page (72) Inventor Noriharu Niitani 5 Kinuokaoka, Moka-shi, Tochigi Oriental Construction Co., Ltd. (72) Inventor Tomotaka Onizuka 5-3-3 Higashi-Hachiman, Hiratsuka-shi, Kanagawa Pref. (72) Inventor Jin Tazawa 1-2-27 Miyashita, Sagamihara-shi, Kanagawa F-term in Asahi Glass Matex Co., Ltd. 2D059 AA07 AA08 BB39 GG01 GG55 2E163 FA12 FD21 FD25 FF52

Claims (5)

[Claims] 1. A structural member having a cross section of an I shape, a T shape or a box shape, a web made of FRP laminated panels is provided between upper and lower flanges made of concrete, and inserted into the lower flange concrete, or the lower flange concrete is inserted. The PC steel material is extended in the axial direction of the member by passing through the inside of the diverter provided in the above, and the PC steel material is tensioned to introduce a prestress.
RP concrete composite structure. 2. The FRP concrete composite structure according to claim 1, wherein the FRP laminated panels are laminated so that the fiber directions of the respective layers cross each other. 3. The FRP concrete composite structure according to claim 1, wherein the FRP laminated panel is provided with an ultraviolet ray blocking layer on an uppermost layer of a surface irradiated with ultraviolet rays. 4. The structural member having a box-shaped cross section, wherein an FRP laminated panel is provided with an anti-buckling member extending in a vertical direction on an outer surface at a predetermined interval.
4. The FRP concrete composite structure according to any one of Items 1 to 3. 5. The FRP laminated panel includes a reinforcing fiber component and a matrix resin component, wherein the liquid crystal thermosetting resin as the matrix resin component is impregnated into the reinforcing fiber component and cured. The FRP concrete composite structure according to any one of claims 1 to 4.