JP4252617B1 - Composite floor slab bridge - Google Patents

Abstract

A composite floor slab using a composite girder that can reduce the height of the girder and increase the width of the girder, and further reduce the number of places to be laterally tightened with a tension material when juxtaposed in the width direction. The issue is to provide a bridge.
A composite floor slab bridge is formed with a pair of support portions 22 and 22 that support both ends in the width direction of a floor slab 21, and a cross-sectional shape in a bridge axis direction is a concrete member 20 having a portal shape. And the composite girder 10 of the composite structure comprised from the steel plate 30 (steel material) attached to the lower surface of each support part 22 and 22 is used, It is characterized by the above-mentioned.
[Selection] Figure 1

Description

The present invention relates to a composite floor slab bridge using a composite girder having a composite structure in which a concrete member and a steel material are combined.

As a bridge using a main girder made of concrete, as shown in FIG. 8 (a), a main girder 210 made of concrete is formed by a precast member having a hollow section, and a plurality of main girder 210. There is a bridge 200 arranged in parallel (see, for example, Patent Document 1).
In the bridge 200 using such a concrete main girder 210, the side-by-side main girders 210... Are laterally tightened with PC steel wires. In the main girder 210 having a hollow cross section as shown in FIG. 8 (a), the effective cross section (floor slab thickness) with respect to the cross sectional force (bending moment etc.) in the width direction is set to the floor slab of a general prestress concrete girder bridge. Therefore, it is possible to reduce the number of places where the main girders 210... Are laterally tightened and to reduce the construction cost when the bridge 200 is installed.

In construction sites where the span length is small, such as a traffic route or a river, it is desired to reduce the girder height of the main girder 210 because the space under the girder is limited.
Further, when the number of main girders 210 arranged side by side in the width direction is small, the manufacturing cost of the bridge 200 can be reduced, and the man-hours for installing the bridge 200 can be reduced. Therefore, it is desirable to increase the width of the integral main beam 210 and to secure the set width with a small number of main beams 210.

When the concrete main girder 210 is installed between the supports, a compressive force in the bridge axis direction acts on the upper part of the main girder 210, and a tensile force in the bridge axis direction acts on the lower part of the main girder 210. Since concrete has a low yield strength against tensile force, in the conventional concrete main girder 210, a large number of PC steel wires are passed through the lower part of the main girder 210 in the direction of the bridge axis to apply prestress. The tensile strength of the lower part of the girder 210 is increased. Therefore, in the conventional concrete main girder 210, in order to provide many PC steel wires in the lower part, it is necessary to provide a concrete cross section in the lower part of the main girder 210, and the height of the main girder 210 cannot be reduced. .
In addition, when reducing the girder height of the main girder 210, it is necessary to take measures such as providing a steel material on the upper part of the main girder 210 to which the compressive force acts, and the manufacturing cost of the bridge 200 is increased (for example, patents). Reference 2).
Further, the conventional concrete main girder 210 has a large weight, and in order to make the main girder 210 heavy enough to be lifted by a lifting machine such as a truck crane, the girder width of the main girder 210 cannot be increased.

  Therefore, in the conventional concrete main girder 210, the girder height is large, and the manufacturing cost is high and the girder width of the main girder 210 can be increased to be applied to a construction site where the space under the girder is limited. Since this is not possible, there is a problem that the number of main girders 210 necessary for securing the set width increases.

  Therefore, as shown in FIG. 8B, the concrete member 120 formed with the support portion 122 that supports the center portion in the width direction of the floor slab 121, and the steel material 130 attached to the lower surface of the support portion 122, There is a composite floor slab bridge 100 in which a composite girder 110 having a composite structure is formed and a plurality of composite girders 110... Are arranged in the width direction (see, for example, Patent Document 3).

  In this composite floor slab bridge 100, since the tensile strength of the lower part of the composite girder 110 is ensured by the steel material 130 attached to the lower surface of the support part 122, the height of the axial cross section of the composite girder 110 can be reduced. it can. Further, since the weight of the composite girder 110 is smaller than that of the conventional concrete main girder 210 (see FIG. 8A), the girder width can be made larger than that of the conventional concrete main girder 210. it can. As a result, the number of composite girders 110 necessary to secure the set width can be reduced.

JP 2006-169731 A Japanese Patent Laid-Open No. 5-340031 JP 2007-254974 A

  However, in the conventional composite floor slab bridge 100 described above, the side ends of the floor slab 121 of each composite girder 110... Are not supported. It is necessary to resist the bending moment in the width direction by providing a large number of bridges at narrow intervals in the bridge axis direction, and there is a problem that the construction cost of the composite floor slab bridge 100 increases.

In the present invention, the above-mentioned problems can be solved, the girder height can be reduced and the girder width can be increased, and further, the number of places to be laterally tightened with a tension material when arranged in the width direction can be reduced. it is an object of the present invention to provide a multi-Goyuka version of Bridge that.

In order to solve the above-mentioned problem, in the composite floor slab bridge of the present invention, a pair of support portions that support both ends of the width direction of the floor slab are formed, the cross-sectional shape in the bridge axis direction is a gate shape , and the entire upper surface is A plurality of composite girders of a composite structure composed of a concrete member forming a flat composite part and a flat steel material attached to the lower surface of each support part are arranged side by side in the width direction, on the upper surface of the steel material A plurality of fixing members project, each fixing member is embedded in a lower end portion of the support portion, and due to the fixing force between the concrete of the support portion and each fixing member, the upper surface of the steel material is The concrete member is formed with a lateral fastening portion having a rectangular cross-sectional shape in the direction of the bridge axis, and is penetrated through the lateral fastening portions of the composite girders arranged side by side in the width direction. Each composite girder is laterally tightened The steel material is attached between the lateral fastening portions formed at both ends in the bridge axis direction of the concrete member, and the lower surfaces of the both ends in the bridge axis direction of the concrete member It is characterized in that the lower surface of the fastening portion is exposed .

In the present invention, the tensile strength of the lower part of the composite girder is secured by the steel material attached to the lower surface of the support part, and it is not necessary to increase the cross section of the lower part of the composite girder. Can be reduced.
In the present invention, since the weight of the composite girder is reduced, the girder width can be made larger than that of the conventional concrete main girder with the same weight as that of the conventional concrete main girder. As a result, the number of composite girders required to secure the set width can be reduced, thus reducing the production cost of the composite floor slab bridge and reducing the work man-hours when constructing the composite floor slab bridge. Can be reduced.
In addition, the cross-sectional shape of the composite girder in the bridge axis direction is a gate shape, both ends of the floor slab are supported in the width direction, and when multiple composite girders are arranged side by side in the width direction, each composite girder is joined The effective cross-section in the width direction at the joining position in the bonded state can be made larger than the effective cross-section of the conventional composite girder, so the number of places where each composite girder is laterally tightened with a tension material can be reduced, and the composite The construction cost of the floor slab bridge can be reduced.
Further, in the present invention, when the composite girder is loaded on the loading platform of the transport vehicle, the floor slab is supported by the pair of support portions arranged in the width direction, so that stability when transporting the composite girder is improved. Can do.
Moreover, since the manufacturing cost of steel materials can be reduced by using a flat member, it is not necessary to join steel materials by welding etc., Therefore The fatigue durability of steel materials can be improved.
Further, the steel material is attached to the lower surface of the support portion by the fixing force between the fixing member and the concrete. Therefore, the steel material can be easily attached to the concrete member, and the concrete member and the steel material can be firmly joined.

In addition, the cross-sectional shape of the composite girder in the bridge axis direction is a gate shape, both ends of the floor slab in the width direction are supported, and the effective cross-section in the width direction at the joining position in the state where each composite girder is joined Since it can be taken larger than the effective cross section of the conventional composite girder, the number of places where each composite girder is laterally fastened with a tension material can be reduced, and the construction cost of the composite floor slab bridge can be reduced.

In the composite floor slab bridge described above, the composite girder can be constituted by a precast member.
In this configuration, since the composite girder is manufactured in advance at a factory or the like, the construction period at the construction site can be shortened. In addition, since concrete is formed by placing concrete in a formwork at a factory or the like, the dimensional accuracy of the composite girder can be increased.

According to the present invention, since it is not necessary to increase the lower cross section of the composite girder, the height of the axial cross section of the composite girder can be reduced.
Also, with the same weight as a conventional concrete main girder, the girder width can be made larger than that of a conventional concrete main girder, and the number of composite girder required to secure the set width is reduced. Therefore, the manufacturing cost of the composite floor slab bridge can be reduced, and the number of work steps when constructing the composite floor slab bridge can be reduced.
Also, when multiple composite girders are juxtaposed in the width direction, the effective cross-section in the width direction at the joining position when each composite girder is joined can be made larger than the effective cross-section of the conventional composite girder. In addition, it is possible to reduce the number of places where each composite girder is laterally tightened with a tension material, and to reduce the construction cost of the composite floor slab bridge.
Moreover, since a floor slab is supported by a pair of support part arrange | positioned in the width direction, stability at the time of conveying a composite girder can be improved.

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
In the present embodiment, as shown in FIG. 7, the composite floor slab bridge 1 is constructed between the support portions 2 and 2 formed on both banks of the river, and the span length is 16 m or less, The composite floor slab bridge 1 having a width of about 10 m will be described as an example.

  The composite girder 10 is a precast member manufactured in a factory or the like, and has a composite structure in which a concrete member 20 having a reinforced concrete structure and a flat steel plate 30 are combined as shown in FIG. In this embodiment, as shown in FIG. 5, the set width is secured by juxtaposing the composite girder 10... In the width direction.

  As shown in FIGS. 2 (a) and 2 (b), the concrete member 20 has a lateral fastening portion 20a having a rectangular cross-sectional shape in the bridge axis direction at a plurality of positions spaced apart in the bridge axis direction. Are formed (see FIG. 3 (b)), and a composite portion 20b is formed between the lateral fastening portions 20a, 20a. 3 (a)). In addition, although the position and space | interval which provide the horizontal fastening part 20a are not limited, if the span length is about 16m like this embodiment, from both ends of a bridge axis direction and both ends of a bridge axis direction What is necessary is just to form in four places with the position of a space | interval of about 4 m.

  As shown in FIGS. 1A and 1B, the composite portion 20b of the concrete member 20 supports a horizontal plate-like floor slab 21 and both ends of the floor slab 21 in the width direction. Vertical plate-like support portions 22 and 22 are formed, and the cross-sectional shape in the bridge axis direction is a gate shape. The composite part 20b comprises the composite structure by attaching the steel plates 30 and 30 to the lower surface of each support part 22 and 22, respectively.

  As shown in FIGS. 2 (a) and 2 (b), through holes 23 penetrating in the width direction from one side surface to the other side surface are formed in the lateral fastening portion 20a of the concrete member 20 at four locations. Yes. Each through-hole 23 ... penetrates substantially the center of the lateral fastening portion 20a in the width direction, and is arranged at four locations on the top, bottom, left, and right in a side view.

  Further, as shown in FIGS. 3A and 3B, side surface grooves 24 and 24 that are offset toward the inner side in the width direction are formed on both side surfaces of the concrete member 20 in the width direction. The side surface groove portion 24 is formed in the height direction from the upper surface of the concrete member 20 to the vicinity of the lower surface, and as shown in FIG. 2 (b), from one end portion to the other end portion of the concrete member 20 in the bridge axis direction. It is formed over.

  As shown in FIG. 1B, the steel plate 30 is a flat steel material, and the upper surfaces of the two steel plates 30 and 30 are respectively attached to the lower surfaces of the support portions 22 and 22 of the concrete member 20. As shown in FIG. 2A, the steel plate 30 is attached between the lateral fastening portions 20a, 20a formed at both ends of the concrete member 20 in the bridge axis direction, and the width of the support portion 22 is It is composed of a single plate member having substantially the same width. And in the state which attached the steel plate 30 to the lower surface of the support part 22, the lower surface of the steel plate 30 and the lower surface of each horizontal fastening part 20a of the both ends of a bridge axis direction are the same.

  On the upper surface of the steel plate 30, as shown in FIG. As shown in FIG. 3A, the stud gibber 31 is a rod-like member having an enlarged upper end portion, and is embedded in the lower end portion of the support portion 22 of the concrete member 20, so A fixing member for fixing. Therefore, the steel plate 30 is attached to the lower surface of the support portion 22 by the fixing force between the plurality of stud gibbles 31... And the concrete of the support portion 22, and the steel plate 30 is attached to the lower surface of the support portion 22. It is in a state.

  In addition, since the steel plate 30 is exposed to the outside, by using a weather-resistant steel material or applying a rust prevention treatment to the surface of the steel plate 30 to prevent the steel plate 30 from generating rust, Easy maintenance. As the rust prevention treatment of the steel sheet 30, there are a method of applying a rust prevention paint to the surface, a method of spraying a coating material on the surface, or a method of plating the surface.

Next, a procedure when the composite floor slab bridge 1 using the composite girder 10 described above is installed between the support portions 2 and 2 formed on both banks of the river shown in FIG. 7 will be described.
First, the composite girder 10 shown in FIGS. 2 (a) and 2 (b) is manufactured in a factory, loaded on a loading platform of a transport vehicle such as a truck, and transported to a construction site.
When the composite girder 10 is manufactured at the factory, the steel plate 30 is placed in a formwork in which reinforcing bars are arranged, and the stud gibbles 31... The steel plate 30 is attached to the lower surface of the support portion 22 by forming concrete member 20 by placing concrete in the mold so as to be embedded in the frame. Thus, the construction period in a construction site can be shortened by manufacturing composite girder 10 beforehand at a factory etc. Moreover, since the concrete member 20 is formed by placing concrete in a mold at a factory or the like, the dimensional accuracy of the composite girder 10 can be increased.

The composite girder 10 carried into the construction site is lifted by a lifting machine such as a truck crane, and both ends in the bridge axis direction of the composite girder 10 are attached to the support parts 2 and 2 shown in FIG. , 2, the composite girder 10 is installed.
Subsequently, the other composite girder 10 is lifted by a lifting machine, and the two composite girders 10 and 10 are juxtaposed in the width direction as shown in FIGS. By connecting the side groove portions 24, 24 formed on the side surfaces of the adjacent composite girders 10, 10, a concave filling groove 25 is formed between the composite girders 10, 10. Further, the through holes 23 and 23 of the adjacent composite girders 10 and 10 are communicated with the filling groove 25 by arranging the communication pipe 23a.
In the present embodiment, a gap is formed between the lower ends of the adjacent composite girders 10 and 10. This gap is formed in consideration of manufacturing errors and installation errors of the composite girder 10, and it is not necessary to form a gap between the adjacent composite girders 10 and 10.

In the same manner as in the construction procedure of the two composite girders 10 and 10, the composite girders 10 are sequentially arranged in the width direction, so that as shown in FIG. The composite girder 10.
Further, the filling groove 25 formed between the adjacent composite beams 10 and 10 is filled with concrete 26 as a filler.

  Subsequently, as shown in FIG. 5 and FIG. 6 (b), the PC steel wires 27... Are respectively inserted into the through holes 23... Formed in the lateral fastening portions 20 a of the composite girders 10. .. is penetrated and both ends of the PC steel wire 27 are fixed to the side surfaces of the composite girders 10 and 10 arranged at both ends in the width direction. Thereby, each horizontal fastening part 20a ... of each composite girder 10 ... is laterally fastened by the PC steel wire 27.

  Further, as shown in FIGS. 6 (a) and 6 (b), asphalt pavement 40 is constructed on the upper surface of each composite girder 10... And the ground is placed on each composite girder 10 and 10 disposed at both ends in the width direction. By providing the coverings 51 and 51 and the railings 50 and 50, as shown in FIG. 7, the composite floor slab bridge 1 constructed between the support parts 2 and 2 provided on both banks of the river is completed.

The composite floor slab bridge 1 and the composite girder 10 configured as described above have the following effects.
In the composite girder 10, as shown in FIG. 3A, the tensile strength of the lower part of the composite girder 10 is secured by the steel plates 30 and 30 attached to the lower surfaces of the support portions 22 and 22, respectively. Since there is no need to increase the cross section of the lower portion of the ten, the height of the axial cross section of the composite beam 10 can be reduced.

  Further, since the weight of the composite girder 10 is reduced, the girder width can be made larger than that of the conventional concrete main girder with the same weight as that of the conventional concrete main girder 210 (see FIG. 8A). it can. As a result, the number of composite girders 10 necessary to secure the set width can be reduced, so that the production cost of the composite floor slab bridge 1 is reduced and the composite floor slab bridge 1 is installed. Work man-hours can be reduced.

  Further, as shown in FIG. 6A, the cross-sectional shape of the composite girder 10 in the bridge axis direction is a gate shape, and both end portions in the width direction of the floor slab 21 are supported, and a plurality of composite girder 10. .. When the parallel girder 10 is arranged in the width direction, the effective cross section in the width direction at the joining position in a state where each composite girder 10... Is joined is effective for the conventional composite girder 110 (see FIG. 8B). Since it can take large compared with a cross section, the place which carries out the horizontal fastening of each composite girder 10 ... can be decreased, and the construction cost of the composite floor slab bridge 1 can be reduced.

  Further, when the composite girder 10 is loaded on the loading platform of the transport vehicle, the floor slab 21 is supported by the pair of support portions 22 and 22 arranged in the width direction as shown in FIG. The stability when conveying 10 can be improved.

  Further, by using the flat steel plate 30 as the steel material to be attached to the concrete member 20, it is possible to reduce the manufacturing cost of the steel material, and it is not necessary to join the steel materials by welding or the like. Can be increased.

  Further, the steel plate 30 is attached to the lower surface of the support portion 22 by the fixing force between the plurality of stud gibbles 31... Projecting from the upper surface of the steel plate 30 and the concrete of the support portion 22 of the concrete member 20. Therefore, the steel plate 30 can be easily attached to the concrete member 20, and the concrete member 20 and the steel plate 30 can be firmly joined.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.

For example , in the present embodiment, the steel plate 30 is attached to the lower surface of the support portion 22 by the fixing force between the stud gibber 31 protruding from the upper surface of the steel plate 30 and the concrete of the support portion 22 of the concrete member 20. The shape and the number of fixing members protruding from the upper surface of the steel plate 30 are not limited. The fixing member protrudes from the upper surface of the steel plate 30 using a rod-shaped member such as a bolt or a reinforcing bar or a vertical plate-shaped member as a fixing member. Also good.

  Moreover, in this embodiment, as shown in FIG.6 (b), although each composite girder 10 ... is laterally clamped by the PC steel wire 27, for compounding each composite girder 10 ... laterally, The configuration of the tendon is not limited.

  Moreover, in this embodiment, as shown in FIG. 7, although the some horizontal fastening part 20a ... is provided in the composite floor slab bridge 1, the position and number which provide the horizontal fastening part 20a are not limited. And can be set based on design conditions such as the length and width of the composite floor slab bridge 1 in the bridge axis direction.

In the present embodiment, as shown in FIG. 4A, a filling groove 25 is provided between adjacent composite girders 10 and 10, and the filling groove 25 is filled with concrete 26. The filler filled between the adjacent composite girders 10 and 10 is not limited, and various fillers such as mortar and resin material can be used.
Further, in the present embodiment, a gap is formed between the adjacent composite girders 10 and 10, but the side surfaces of the adjacent composite girders 10 and 10 may be brought into close contact with each other. In this case, it is desirable to improve the adhesion of each composite girder 10 and 10 by forming the side surface of the other composite girder 10 by the match casting method using the side surface of one composite girder 10 as a formwork.

It is the figure which showed the composite girder of this embodiment, (a) is the perspective view seen from upper direction, (b) is the perspective view seen from the downward direction. It is the figure which showed the composite girder of this embodiment, (a) is a side view, (b) is a top view. It is the figure which showed the composite girder of this embodiment, (a) is AA sectional drawing of FIG.2 (b), (b) is a BB arrow line view of FIG.2 (b). It is the figure which showed the state which arranged the composite girder of this embodiment side by side in the width direction, (a) is sectional drawing of the state which joined two composite girders, (b) is the state which joined two composite girders FIG. It is the top view which showed the edge part of the bridge axis direction of the composite floor slab bridge of this embodiment. It is the figure which showed the composite floor slab bridge of this embodiment, (a) is CC sectional drawing of FIG. 5, (b) is a DD arrow line view of FIG. It is the side view which showed the composite floor slab bridge of this embodiment. It is the figure which showed the conventional bridge and the composite floor slab bridge, (a) is sectional drawing of the structure using the main girder made from concrete, (b) is sectional drawing of the structure using the composite girder of a composite structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite floor slab bridge 2 Bearing part 10 Composite girder 20 Concrete member 20a Lateral fastening part 20b Composite part 21 Floor slab 22 Support part 25 Filling groove part 26 Concrete 27 PC steel wire 30 Steel plate (steel material)
31 Stud gibber (fixing member)

Claims (2)

A pair of support portions that support both ends of the width direction of the floor slab, a concrete member that forms a composite portion in which the cross-sectional shape in the bridge axis direction is a gate shape and the entire upper surface is flat ;
A plurality of composite girders of a composite structure composed of a plate-shaped steel material attached to the lower surface of each support portion are arranged in the width direction,
A plurality of fixing members project from the upper surface of the steel material, and each fixing member is embedded in a lower end portion of the support portion. By the fixing force between the concrete of the support portion and each fixing member, the upper surface of the steel material Is attached to the lower surface of the support ,
The concrete member is formed with a lateral fastening portion in which a cross-sectional shape in the bridge axis direction is formed in a rectangular shape,
Each composite girder is laterally tightened by a tension material that penetrates each lateral tightening portion of each composite girder arranged side by side in the width direction,
The steel material is attached between the lateral fastening portions formed at both ends of the concrete member in the bridge axis direction, and the lower surfaces of the both ends of the concrete member in the bridge axis direction are below the bottom surfaces of the lateral fastening portions. A composite floor slab bridge characterized by the fact that it is exposed . The composite floor slab bridge according to claim 1, wherein the composite girder is a precast member.

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