JP2001200608A - Upper structure of bridge or the like and construction method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an upper structure of a bridge or the like simple in structure, facilitating maintenance and control after construction and having good workability of construction allowing execution even in the case of a narrow space under the girder to limit the dimensions under the road surface and a construction method therefore. SOLUTION: This upper structure is provided with girders 2 and floor systems 30 laid to bridge on the support parts 6 of the adjacent girders 2, and the girders 2 are so constructed that plural steel shells 3 having a substantially U-shaped or box-shaped section, provided with opening parts at designated spaced in the longitudinal direction, and having the support part 6 on the lower bridge surface side are installed at designated spaces in the cross direction of a bridge pier or on an abutment and the interior of each steel shell 3 is filled with concrete 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of girders having a supporting portion on the lower bridge surface side, comprising a steel shell filled with concrete inside, and being installed at predetermined intervals on a pier or abutment. The present invention relates to a superstructure such as a bridge having a slab laid therebetween and a method of constructing the same.

[0002]

2. Description of the Related Art As a composite floor slab used for a superstructure such as a bridge, there is an invention described in, for example, JP-A-7-173895. The composite floor slab according to the present invention is a method in which a plurality of steel girders or metal pipes arranged in parallel are implanted with stud dowels that transmit shear force to the upper surface of the steel girders or metal pipes, and concrete is cast thereon, and the steel girders or metal girders Both ends of the pipe are covered with concrete at the ends.

[0003] Then, with such a configuration,
It is possible to omit the complicated production and processing of steel materials such as performed with a plate girder, save labor, speed up construction, and reduce costs.In addition, both ends of a steel girder or metal pipe are covered with concrete at the ends. By doing so, a strong steel-concrete composite structure can be obtained.

[0004]

When the composite slab as described above is used as a superstructure of a bridge, there are the following problems. (1) If the floor slab is damaged, such as cracking of the slab or neutralization of the slab concrete, the slab itself constitutes a part of the main member. Can not. Therefore, if the floor slab is damaged, the entire girder must be replaced. In addition, when repainting a steel girder or a metal pipe, it is necessary to assemble a scaffold at a lower portion, which requires a lot of time and labor, so that there are many problems in maintenance and management such as low economic efficiency.

(2) Further, since the dimension below the road surface is large, in a bridge section where it is necessary to secure a space below the girder,
This composite slab cannot be implemented. In order to secure the space under the girder of this bridge, an approach of gradually raising the road surface is necessary, which significantly increases the bridge length and construction costs.

(3) When transporting and assembling a composite member assembled in a factory, the weight of each individual member becomes large, so large equipment is required at the time of installation, which is uneconomical. Not only that, but also poor workability. (4) In addition, when concrete is cast on site after steel girders or steel pipes are erected, a formwork for concrete casting is necessary, and therefore the workability is poor and time is required for construction. Therefore, the construction period is prolonged.

The present invention has been made in order to solve the above-mentioned problems, and has a simple structure, easy maintenance and management after construction, and a small space under the girder, so that dimensions under a road surface are limited. It is an object of the present invention to obtain a superstructure such as a bridge and the like and a construction method which can be implemented even in a case and has good workability.

[0008]

(1) An upper structure of a bridge or the like according to the present invention has a substantially U-shaped cross section or a box-shaped cross section, provided with openings at predetermined intervals in a longitudinal direction, and a lower bridge surface. A plurality of steel shells having a support portion on the side are installed at predetermined intervals in the width direction on the pier or abutment, and a girder filled with concrete inside, and a bridge are laid on the support portion of the adjacent girder. And a floor slab.

(2) The opening of the above (1) is formed by alternately providing holes of a circular shape, an elliptical shape, a rectangular shape, or the like, or holes of a triangle and an inverted triangle.

(3) The upper structure of a bridge or the like according to the present invention is formed in an arch shape having a substantially U-shaped cross section or a box-shaped cross section and a central portion in the longitudinal direction having a maximum height, and a lower bridge surface side. A steel shell having a support portion is installed at a predetermined interval in the width direction on the pier or abutment, and a girder filled with concrete therein, and a floor slab laid by bridging on the support portion of the adjacent girder. It is provided with.

(4) In the longitudinal direction of the beam of (3), a plurality of openings are provided, the ends of which are small and the center is large.

(5) A diaphragm is provided in the steel shell of (1) to (4), and (6) a stiffener is provided on the inner wall of the steel shell of (1) to (5). (7) Further, a multilayer bridge surface is provided on the upper structure of (1), (2), (5), or (6).

(8) According to the method for constructing a superstructure such as a bridge according to the present invention, openings are provided at predetermined intervals in the longitudinal direction in a substantially U-shaped cross section or a box-shaped cross section. A step of installing a plurality of steel shells having a support portion on the lower bridge surface side at predetermined intervals in the width direction on the pier or abutment, the center portion being formed in an arch shape having the maximum height, The method includes a step of filling concrete and a step of laying a floor slab by bridging on a support portion of the adjacent steel shell.

(9) Further, openings are provided at predetermined intervals in the longitudinal direction in a substantially U-shaped cross section or a box-shaped cross section, or an almost central portion in the longitudinal direction is formed in an arch shape having a maximum height, and the lower portion is formed. Installing a plurality of girders filled with concrete inside a steel shell having a supporting part on the bridge surface side at predetermined intervals in the width direction of the pier or abutment, and bridging on the supporting part of the adjacent girders And laying the floor slab.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] FIG. 1 is a schematic side view showing a part of a cross-section for explaining an entire structure of a superstructure such as a bridge according to Embodiment 1 of the present invention. 2 is FIG.
It is the perspective view seen from diagonally below. In both figures, reference numeral 1 denotes an upper structure of a bridge, which has a support portion 6 at a lower end portion, is installed on a pier P (or an abutment) erected on the ground G at predetermined intervals in the width direction, and has a longitudinal structure. A plurality of openings 7 are provided at predetermined intervals in the direction and a plurality of girders 2 made of a steel shell 3 filled with concrete 20 therein, and the bridges are laid between the supporting parts 6 of the adjacent girders 2. And a precast floor slab 30 (hereinafter simply referred to as a floor slab).

The steel shell 3 has a length corresponding to, for example, the span of the bridge, and has a predetermined width (height) provided with a plurality of openings 7 having, for example, a circular shape, an elliptical shape, or a rectangular shape at predetermined intervals in the longitudinal direction. 2), the two steel plates 4a and 4b are opposed to each other at a predetermined interval, and the inner peripheral edges of the opposed openings 7 are welded and closed by bridging with a closing plate 8 made of a steel plate. And steel plate 4
a bottom plate 5 made of a steel plate having the same length as the steel plates 4a and 4b and having a width wider than the interval between the steel plates 4a and 4b,
As shown in FIG. 3 (a), the steel shells 3 on both sides have one edge aligned with the side wall of the steel plate 4a (or 4b), so that the other edge is aligned with the side wall of the steel plate 4b (or 4a). From the center and welded together by welding.
As shown in FIG. 3 (b), the bottom plate 4 is formed to have a substantially U-shaped cross section with an upper opening by projecting the bottom plate 4 to both sides and joining them by welding.
The supporting portion 6 of the floor slab 30 is formed by the projecting portion b or 4a, 4b).

In the above description, the case where the steel shell 3 is formed to have a substantially U-shaped cross section with an upper opening is shown, but the upper opening may be formed into a box-shaped cross section by closing it with a steel plate. In this case, it is necessary to provide an injection hole for injecting concrete into the steel plate.

Reference numeral 30 denotes a floor slab manufactured in advance in a factory or the like, the width of which is slightly smaller than the inner dimension between the adjacent girders 2 and is formed to a predetermined length. As shown in FIG. 4, a shearing joint key 31 composed of, for example, triangular or trapezoidal projections and depressions is formed.

Next, an example of the construction method of the present embodiment configured as described above will be described. (1) A plurality of steel shells 3 and a plurality of floor slabs 30 manufactured in a factory.
Is transported to the construction site, and as shown in FIG.
Are installed at predetermined intervals in the width direction on the bridge girder P.
At this time, the steel shells 3 installed on both sides have the support portions 6 positioned inside, and the steel shells 3 having the support portions 6 on both sides are installed at the center. The steel shell 3 installed at the center may be higher or lower than the other steel shells 3 (the same applies to other embodiments).

(2) Next, the concrete 20 is filled into the steel shell 3 from an upper opening (a pouring hole in the case of a box-shaped cross section). Note that the girder 2 in which the concrete 20 is filled in the steel shell 3 in advance may be installed on the pier P (or the abutment).

(3) After the concrete 20 has hardened,
A mortar, an elastic material 9 or the like is laid on the upper surface of the support portion 6 of each girder 2, and a floor slab 30 is placed thereon and bridged by bridging the adjacent support portions 6. Note that the floor slab 30 may be directly placed on the support portion 6 without laying the mortar 9 or the like. At this time, the floor slab 30 adjacent to the traveling direction of the vehicle or the like is made of epoxy resin,
They are sequentially joined by a shear joining key 31 via a mortar or the like.

[Examples] The specifications of the superstructure such as a bridge according to the present embodiment are variously changed according to the type and scale of the target structure. It is as follows. Steel shell 3 is 9mm thick,
Height 5m, length 40m, diameter 3 at 4m intervals in the longitudinal direction
m, two steel plates 4a, 4b provided with a circular opening 7
Are opposed to each other with a gap of 0.5 m, and a closing plate 8 having a thickness of 9 mm is bridged to the inner peripheral edge of each opening 7 and joined by welding, and a thickness of 38 mm is attached to lower ends of the steel plates 4a and 4b. , Width 0.7
A bottom plate 5 made of a steel plate having a length of 40 m and a length of 40 m is joined by welding so that one side thereof is aligned with the side wall of one steel plate (for example, 4a), and the other side is separated from the side wall of the other steel plate 4b.
The supporting portion 6 was formed to project by 2 m. Further, a bottom plate 5 made of a steel plate having a thickness of 38 mm, a width of 0.9 m, and a length of 40 m is protruded from both side walls of both steel plates 4 a and 4 b by 0.2 m at the lower end of the central steel shell 3 by welding. It joined and the support part 6 was formed by the protrusion part.

Each of the steel shells 3 constructed as described above was transported to the site, placed on the pier P at intervals of 4.5 m, and the steel shells 3 were filled with concrete 20. After the concrete 20 has hardened, a mortar of about 10 mm thickness is laid on each support portion 6, and a floor slab 20 having a thickness of 30 cm, a width of 4 m and a length of 2 m is placed on the mortar, and the traveling direction of the vehicle or the like Are connected to each other by an epoxy resin via a shear bonding key 31 so that
Joined.

In the upper structure of the bridge and the like according to the present embodiment configured as described above, the steel shell 3 is mechanically responsible for the main stress as a girder, and the floor slab 30 is the main stress as a girder. It plays a role of propagating the live load to the steel shell 3 without taking charge.

Further, since the floor slabs 30 are individually joined to the girders 2, if the floor slabs 30 are damaged, only the floor slabs need to be replaced, and the replacement is easy. Furthermore, since most of the girders 2 are above the road surface, the steel material can be painted from the road surface position, and thus no scaffolding is required. For these reasons, the present invention is extremely effective in maintenance and management.

Further, since the lower part of the spar 2 is substantially equal to the road surface height, the space below the floor slab 30 requires almost no structural members. As a result, a significantly larger space under the girder than the conventional synthetic slab can be secured, and even under conditions where the girder height is narrow, it is possible to design a route that minimizes the height of the line following it. is there. This reduces the scale of the bridge and can significantly reduce construction costs.

Further, the steel shell 3 having the supporting portion 6 for supporting the floor slab 30 for forming the bridge surface is installed on the pier P or the abutment. Then, the steel shell 3 is filled with the concrete 20 and the girder. 2 and the floor slab 30 is laid on the support portion 6 of the spar 2 after the concrete 20 has hardened, so that a formwork for concrete casting is unnecessary. Further, when the concrete 20 is poured into the steel shell 3 at the site, it is not necessary to carry a heavy object and erection, so that high workability is provided.

Further, since a plurality of openings 7 are provided at predetermined intervals in the longitudinal direction of the spar 2, the spar 2 is not only lighter and the workability is improved, but also the visibility of the driver when passing the vehicle. And the running performance is improved. Furthermore, since it is a steel shell structure of a concrete filling type, buckling design of steel material is unnecessary, and design is easy. Furthermore, since there are many variations of the structure forming formula, the shape can be changed according to the plan.

FIG. 5 is a schematic side view showing the overall structure of another example of the present embodiment, and FIG. 6 is a perspective view of the upper structure of FIG. 5 viewed obliquely from below. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted. In this example, triangular and inverted triangular openings 7a are provided alternately at predetermined intervals in the longitudinal direction of the steel plates 4a and 4b constituting the steel shell 3,
The steel plates 4a and 4b are arranged facing each other, and the inner peripheral edge of each opening 7a is bridged and welded by a closing plate 8 to be closed.

Also in this example, it is installed by the same construction method as the examples of FIGS. 1 and 2, and substantially the same effect can be obtained.
Further, since the truss shape is formed by opening a portion where the amount of generated stress is small, the weight of the steel shell 3 can be reduced with a slight decrease in the load carrying capacity.

FIG. 7 is a sectional view showing still another example of the present embodiment. In the example of FIG. 2 and FIG. 6, the case where three girders 2 are installed at predetermined intervals in the width direction on the pier P is shown.
In this example, two girders 2 each having a support portion 6 at the bottom are installed at predetermined intervals on a pier P (or an abutment) with the support portion 6 inside, and a mortar 9 or the like is laid on the support portion 6 and the floor. The plate 30 is laid. Although the construction method, effects, and the like of this example are the same as those in the example of FIG. 2, it is particularly effective to install it in a place with a relatively small traffic volume or a narrow place. In each of the above examples, two or three girders 2 are provided on the pier P or the abutment. However, four or more girders 2 may be provided. This example can also be implemented in the following embodiments.

[Second Embodiment] FIG. 8 is a schematic side view showing the entire structure of a second embodiment of the present invention, and FIG. 9 is a perspective view of the upper structure of FIG. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the height of the steel shell 3a in the longitudinal direction is gradually increased so that the steel shell 3a is formed into an arch shape having a maximum height almost at the center of the span of the bridge, and concrete 20 is filled in the arch to fill the girder. 2.

Although not shown, in the present embodiment, similarly to the first embodiment, a hole such as a circle, an ellipse, or a rectangle, or a triangle and an inverted triangle is formed in the longitudinal direction of the spar 2. A plurality of openings in which holes are provided alternately may be formed. In this case, it is desirable to form the openings at both ends in the longitudinal direction of the spar 2 small and to make the openings at the center part large.

The construction method of the present embodiment is the same as that of the first embodiment.
However, in the embodiment, in the steel plates 4c and 4d having a length of 40 m, both ends of the beam 2 having a small member force are reduced (2 m in the embodiment) to reduce the cross-sectional area of the beam 2, Almost the center of the span where the member force is large is raised (in the embodiment, 5
m) to increase the cross-sectional area of the spar 2, so that substantially the same effects as in the first embodiment can be obtained, and in particular, the steel shell 3 can be reduced in weight rationally. Further, by forming the spar 2 in an arch shape, the vertical force acting on the spar 2 applies an axial compressive force to the steel shell 3a for the arch action, so that the bending strength of the steel shell 3a can be improved.

Third Embodiment FIGS. 10 and 11 are perspective views of an upper structure according to a third embodiment of the present invention as viewed obliquely from below. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment, for example, a bridge surface is stacked in two steps so that a large amount of traffic can be consumed in a narrow place.

In the present embodiment, the height of the steel shell 3 described in the first embodiment is formed to be high, and a second stiffener 10 reinforced at a predetermined height above the support portion 6 is provided. A plurality of steel shells 3 provided with support portions 6a are installed on a pier P (or an abutment),
The girder 2 is formed by filling the inside with concrete 20. The floor slab 30 is laid on the lower support 6 and the floor slab 30 is similarly laid on the upper support 6a.
The bridge is composed of a bridge with a multi-story bridge surface.
Are provided with openings 7, 7a corresponding to the upper and lower bridge surfaces, respectively. Although the figure shows the case where the bridge surface is composed of two layers, it may have three or more layers.

As described above, in the present embodiment,
Since the bridge surface was expanded upward without increasing the width of the bridge, the congestion can be reduced with a simple structure even in a narrow place. In this embodiment, the bridge surface may be configured as a multi-layer from the beginning of construction, or a bridge or the like which was initially a single-layer bridge surface as in the first embodiment may be increased in traffic volume. Accordingly, a bridge surface may be additionally provided.

[Embodiment 4] In the following embodiment,
Matters common to the upper structures such as the bridges of the first to third embodiments will be described. Although the structure of the steel shell 3 has been described in the first embodiment (FIG. 3), another embodiment of the steel shell 3 is shown in FIG. FIG. 12A shows that the bottom plate 5 is formed in a triangular shape having a base having a width wider than the interval between the steel plates 4a and 4b (or 4c and 4d, the same applies hereinafter). The support portions 6 are formed by welding to the lower end portions of 4a and 4b and projecting portions. In addition, steel shell 3 (or 3
a, the same shall apply hereinafter), the support portions 6 may be provided on both sides of the steel plates 4a and 4b using wider bases.

FIG. 12 (b) shows the lower part of one of the steel plates (for example, 4a) bent outward at right angles, and a bottom plate 5 welded to the lower end through a vertical piece to form an L-shape. The support portion 6 is formed by a bent portion. In the case where the support portions 6 are provided on both sides of the steel shell 3, the lower portions of the steel plates 4a and 4b may be bent at right angles to form an inverted T-shape, and the support portions 6 may be formed by the bent portions on both sides. Good.

FIG. 12C shows that one steel plate (for example, 4a) is bent obliquely inward and the other steel plate 4b is bent.
, The lower portion is bent outward at a right angle, the bottom plate 5 is welded to the lower end portion via a vertical piece, and the support portion 6 is formed by a bent portion. When the support portions 6 are provided on both sides of the steel shell 3, the support portions 6 may be formed by bending the lower sides of the steel plates 4a and 4b diagonally inward and then bending the lower portions outward at right angles. According to the present embodiment, the strength of the support portion can be further increased. The structure of the support portion 6 provided below the steel shell 3 is not limited to the above, and may be an appropriate structure.

[Fifth Embodiment] FIG. 13 is a perspective view of an upper structure according to a fifth embodiment of the present invention as viewed obliquely from below. The same parts as those in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, diaphragms 11 serving as nodes are provided at regular intervals in a steel shell 3a having a substantially U-shaped cross section or a box-shaped cross section formed in an arch shape. The construction method of the present embodiment is almost the same as that of the first embodiment, but by providing the diaphragm 11, the steel shell 3a and the concrete 20 filled therein can be mechanically integrated. . In addition, although the figure shows the case where the diaphragm 11 is provided in the steel shell 3 of Embodiment 2 formed in an arch shape, Embodiment 1 or Embodiment 3
In the same manner, the diaphragm 11 can be provided in the steel shell 3.

[Embodiment 6] In the present embodiment, FIG.
As shown in (a) to (d), a plurality of stiffeners 12 are provided on the opposing inner walls of a steel shell 3 (or 3a, the same applies hereinafter) provided with various support portions 6 at substantially equal intervals in the vertical direction. It is provided. The stiffener 12 is, for example, as shown in FIG. 15A, made of a steel material having a length substantially equal to that of the steel shell 3 and having an L-shaped cross section in which a plurality of concrete passage holes 13 are provided in a horizontal piece. The vertical piece is joined to the inner wall of the steel shell 3 by welding. 14A to 14C as needed.
The stiffener 12 may be provided on the inner wall of the bottom plate 5 as shown in FIG.

According to the present embodiment, since the plurality of stiffeners 12 are provided on the inner wall of the steel shell 3, the shape of the steel shell 3 is maintained, and the steel shell 3 and the concrete 20 are further integrated. Can be promoted. In the above description, the case where the stiffener 12 having a length substantially equal to that of the steel shell 3 is provided on the inner wall of the steel shell 3 is shown. However, as shown in FIG. The stiffeners 12a may be mounted on the same line on the inner wall of the steel shell 3 at predetermined intervals in the longitudinal direction and in multiple stages in the vertical direction. Further, instead of the L-shaped stiffeners 12 and 12a, I
A letter-shaped stiffener or a plurality of stud dowels may be attached by welding.

[Seventh Embodiment] In the first to third embodiments,
Although the case where mortar or the like 9 is laid on the support portion 6 of the girder 2 and the floor slab 30 is placed thereon has been described, in the present embodiment, as shown in FIG. In order to further unify the joining, the two are joined by a shear joining member 14. That is, FIG.
As shown in FIG. 1A, a bar-shaped shear bonding member 1 such as a plurality of stud dowels is provided on an upper surface of a support portion 6 provided on a steel shell 3.
4 are joined by welding or the like, and holes 32 are provided at positions facing the shear joining members 14 of the floor slab 30, as shown in FIG. 17 (b).

When laying the floor slab 30 on the support portion 6 of the spar 2, mortar 9 or the like is laid on the support portion 6 if necessary, and then the holes 32 provided in the floor slab 30 are It fits and is placed on the support 6. And the hole 32
The mortar or concrete 15 is poured and solidified, whereby the shear bonding member 14 and the floor slab 30 are integrally bonded. Thereby, the floor slab 30 is connected to the shear bonding member 1.
4 and the movement in the front-rear and left-right directions is restricted, so that the spar 2 and the floor slab 30 can be more firmly integrated.

In the above description, the case where a plurality of bar-shaped shear joining members 14 such as stud dowels are provided on the support portion 6 has been described, but a plurality of short L-shaped steel materials are provided in the longitudinal direction of the support portion 6. May be attached at predetermined intervals to form the shear bonding member 14.

[Embodiment 8] In Embodiments 1 to 3, mortar or the like 9 is laid on the support portion 6 of the spar 2 and the floor slab 3 is placed thereon.
0 is mounted, and in the seventh embodiment, the case where the support portion 6 and the floor slab 30 are joined by the shear bonding material 14 has been described, but in the present embodiment, the support portion 6 is placed on the support portion 6. A part of the floor slab 30 is fixed to the support portion 6 by high-strength bolts.

That is, after the concrete 20 filled in the steel shell 3 is hardened, the floor slabs 30 are installed on the support portion 6 at regular intervals (this interval corresponds to the length of the floor slab 30 or a multiple thereof). Then, the floor slab 30 is fixed to the support portion 6 with high-strength bolts (in this case, mortar 9 or the like may be laid on the support portion 6). Then, the mortar 9 is laid directly or on a portion of the support portion 6 where the floor slab 30 is not installed, and the floor slab 30 is placed thereon and joined. According to the present embodiment, floor slab 30 can be more firmly attached to spar 2.

[0049]

(1) The upper structure of a bridge or the like according to the present invention has a substantially U-shaped section or box-shaped section, with openings provided at predetermined intervals in the longitudinal direction, and a support section on the lower bridge surface side. A plurality of steel shells having are installed at predetermined intervals in the width direction on the pier or abutment, and a girder filled with concrete inside, and a floor slab laid by bridging on the support part of the adjacent girder Structured, simple structure, no need for steel shell buckling design, reduced weight, no need for formwork when placing concrete, large space can be secured under the girder, to the top It is possible to obtain remarkable effects such as the possibility of additional route construction, the advantage of maintenance and management after the construction, the widening of the driver's field of view, and the improvement of the running value.

(2) Since the opening in (1) is formed by alternately providing circular, elliptical or rectangular holes, or triangular and inverted triangular holes, the weight of the spar is reduced. Not only the workability is improved, but also the visibility of the driver is widened and the traveling performance is improved. In addition, when triangular and inverted triangular holes are alternately provided, the truss shape is formed by opening a part where the amount of stress generation is small, so the steel shell is reduced in weight with a slight decrease in load capacity. be able to.

(3) The upper structure of a bridge or the like according to the present invention is formed in an arch shape having a substantially U-shaped cross section or a box-shaped cross section and a substantially central portion in the longitudinal direction having a maximum height, and a lower bridge surface. Steel shells with supporting parts on the side are installed at predetermined intervals in the width direction on the pier or abutment, and a girder filled with concrete inside, and a floor slab laid by bridging on the supporting part of the adjacent girder Therefore, the above-mentioned effect (1) is obtained, and in particular, the steel shell can be reasonably reduced in weight. Further, by forming the girder in an arch shape, the vertical force acting on the girder applies an axial compressive force to the steel shell by the arch action, so that the bending strength of the steel shell can be improved.

(4) In the longitudinal direction of the girder of (3), a plurality of openings are provided at both end portions which are small and the center portion is large, so that in addition to the effect of (3), in addition to the effects of (3), Almost the same effects can be obtained.

(5) Since the diaphragm is provided in the steel shell of the above (1) to (4) or the stiffener is provided on the inner wall of the steel shell, the steel shell and the concrete filled therein are separated. It can be more firmly integrated.

(6) In the superstructure such as the bridges of (1), (2) and (5), the bridge surface is multi-layered, so that traffic congestion can be reduced even in a narrow place. In addition, when the traffic volume increases, a bridge surface can be additionally provided on an existing bridge or the like.

(7) According to the method for constructing a superstructure such as a bridge of the present invention, openings are provided at predetermined intervals in the longitudinal direction in a substantially U-shaped cross section or a box-shaped cross section, or substantially the center in the longitudinal direction. A step of installing a plurality of steel shells having a support portion on the lower bridge surface side at predetermined intervals in the width direction on the pier or abutment, wherein the concrete portion is formed in an arch shape having a maximum height, and Since there is a step of filling and a step of laying a floor slab by bridging on a support portion of an adjacent steel shell, not only the effects of the above (1) or (3) are obtained, but also the workability is high. Therefore, the construction cost can be reduced and the construction period can be shortened.

(8) In the method for constructing a superstructure such as a bridge according to the present invention, openings are provided at predetermined intervals in a longitudinal direction in a substantially U-shaped cross section or a box-shaped cross section. A plurality of girders formed in an arch shape having a central portion having the maximum height and filled with concrete inside a steel shell having a supporting portion on the lower bridge surface side are installed at predetermined intervals in the width direction of the pier or abutment. Since the method includes the step and the step of laying the floor slab by bridging on the support portion of the adjacent girder, the same effect as the above (7) can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a part of a cross section for explaining the entire structure of a first embodiment of the present invention.

FIG. 2 is a perspective view of FIG. 1 as viewed obliquely from below.

FIG. 3 is a sectional view of the steel shell of FIG. 2;

FIG. 4 is a sectional view showing an example of the floor slab of FIG. 2;

FIG. 5 is a schematic side view for explaining the overall structure of another example of the first embodiment.

FIG. 6 is a perspective view of FIG. 5 as viewed obliquely from below.

FIG. 7 is a sectional view of still another example of the first embodiment.

FIG. 8 is a schematic side view for explaining Embodiment 2 of the present invention.

FIG. 9 is a perspective view of FIG. 8 as seen from obliquely below.

FIG. 10 is a perspective view of the third embodiment of the present invention as viewed obliquely from below.

FIG. 11 is a perspective view of another example of the third embodiment of the present invention as viewed obliquely from below.

FIG. 12 is an explanatory diagram of a steel shell according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view of an upper structure according to a fifth embodiment of the present invention, as viewed obliquely from below.

FIG. 14 is an explanatory diagram of a steel shell according to a sixth embodiment of the present invention.

FIG. 15 is a perspective view of the stiffener of FIG. 14;

FIG. 16 is an explanatory diagram of a joint state between a steel shell and a floor slab according to Embodiment 7 of the present invention.

FIG. 17 is a perspective view of a main part of the steel shell and the floor slab of FIG. 16;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bridge superstructure 2 girder 3, 3a Steel shell 6, 6a Support part 7, 7a Opening 11 Diaphragm 12, 12a Stiffener 14 Shear connection member 20 Concrete 30 Floor slab 31 Shear connection key 32 hole

Claims (9)

[Claims] 1. A plurality of steel shells having a substantially U-shaped cross section or a box-shaped cross section and having openings provided at predetermined intervals in a longitudinal direction and having a support portion on a lower bridge surface side are formed in a width direction on a pier or abutment. An upper structure, such as a bridge, comprising: a girder that is installed at a predetermined interval and filled with concrete therein, and a floor slab laid on a support portion of the adjacent girder by bridging. 2. The upper structure of a bridge or the like according to claim 1, wherein the opening is formed by alternately providing holes of a circular shape, an elliptical shape or a rectangular shape, or holes of a triangular shape and an inverted triangular shape. 3. A steel shell having a substantially U-shaped cross section or a box-shaped cross section and having a maximum height at a substantially central portion in a longitudinal direction and having a supporting portion on a lower bridge surface side is provided on a pier or abutment. An upper part of a bridge or the like, comprising: a girder installed at a predetermined interval in the width direction and filled with concrete, and a floor slab laid by bridging on a support portion of the adjacent girder. Construction. 4. The upper structure of a bridge or the like according to claim 3, wherein a plurality of openings are provided in the longitudinal direction of the girder, the openings being small at both ends and large at the center. 5. The upper structure of a bridge or the like according to claim 1, wherein a diaphragm is disposed in a steel shell. 6. The upper structure of a bridge or the like according to claim 1, wherein a stiffener is provided on an inner wall of the steel shell. 7. The superstructure of a bridge or the like according to claim 1, further comprising a multilayer bridge surface. 8. A substantially U-shaped cross section or a box-shaped cross section, wherein openings are provided at predetermined intervals in the longitudinal direction, or are formed in an arch shape having a maximum height substantially at the center in the longitudinal direction, and a lower bridge surface is provided. Installing a plurality of steel shells having support portions on the side at predetermined intervals in the width direction on the pier or abutment; filling concrete in the steel shells; And a step of laying a floor slab by bridging. A method for constructing a superstructure such as a bridge. 9. A substantially U-shaped cross section or a box-shaped cross section, wherein openings are provided at predetermined intervals in the longitudinal direction, or an approximately central portion in the longitudinal direction is formed in an arch shape having a maximum height, and a lower bridge surface is provided. Installing a plurality of girders filled with concrete inside a steel shell having a supporting part on the side at predetermined intervals in the width direction of the pier or abutment; and bridging the floor on the supporting part of the adjacent girders And a step of laying a plate.