JP2002227133A - Replacement composite floor board steel girder bridge and constructing and installing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a replacement composite floor board steel girder bridge and its constructing and installing method capable of replacing the floor boards of an RC(reinforced concrete) floor board steel girder bridge applying a reinforcing structure by an under-deck panel construction method with RC floor boards strength-composed with under-deck panels and having high durability at a low cost in a short time. SOLUTION: The under-deck panels 20 are installed between the main girders 11 of the RC floor board steel girder bridge, and the reinforcing structure is provided by the under-deck panel construction method. Connecting structural members 30 are provided on the support steel plates 21 of the under-deck panels 20, and the under-deck panels 20 are strength-composably and integrally connected to the floor boards 12 by the connecting structural members 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced concrete slab steel bridge which is constructed by replacing an existing reinforced concrete slab with a steel plate and reinforced concrete slab to form a bridge.

[0002]

2. Description of the Related Art In a steel girder bridge constructed by supporting a floor slab by a steel main girder extending in the bridge axis direction, a reinforced concrete slab formed of reinforced concrete on the floor slab (hereinafter referred to as an RC slab). ) Is often used.

[0003] RC floor slabs are constructed by providing a formwork on a main girder, assembling a reinforcing bar inside and casting concrete, and a steel girder is a dowel planted on the upper surface of the steel girder. Are buried in the RC slab and connected to transmit shear force.

[0004] Recently, in an existing steel girder bridge using such RC slabs, the RC slabs, which have been damaged by cracks or the like due to an increase in heavy vehicles or insufficient thickness of the slabs, have been applied along the back surface. There is known a reinforcement structure called a so-called under-deck panel construction method in which a steel plate positioned in a horizontal direction is connected to a main girder and reinforced.

That is, as shown in FIG. 9 which is a cross-sectional perspective view of a bridge reinforced by one example, a width direction orthogonal to the bridge axis can cover the lower surface of an RC floor slab 92 excluding a haunch between main girders 91. At the same time, in the bridge axis direction, an underdeck panel 93 of a predetermined length is provided with a bracket 94 on a belly plate of the main girder 91 in a state in which a filler such as resin mortar is interposed between the upper surface and the lower surface of the RC slab 92. It is configured to be fastened via a pin.

The underdeck panel 93 has a plurality of longitudinal ribs 93B extending in the bridge axis direction at predetermined intervals in a direction orthogonal to the bridge axis, on the lower surface side of the supporting steel sheet 93A having a predetermined thickness. The transverse ribs 93C which are orthogonal to each other are arranged at predetermined intervals in the bridge axis direction and are formed firmly, and the side ends of the transverse ribs 93C are fastened and fixed to the bracket 94 with high-strength bolts.

[0007] By applying such a reinforcing structure by the under-deck panel method, it is possible to increase the bending strength and the shear strength and to suppress the progress of damage to the floor slab.

[0008]

However, the RC reinforced by the under deck panel method as described above.
Even in the case of steel deck girder bridges, it will be necessary to replace the decks as they age.

In order to replace the RC slab, it is common to cut and remove the existing RC slab and reconstruct the same RC slab on the main girder as in the previous case. It takes a long time to install a frame and put concrete inside with reinforcing bars inside, which requires a long construction cost, and has high durability because it uses the existing floor group. There was a problem that it could not be achieved with a floor slab. There is also a problem that a traffic regulation period that must be performed during the work extends for a long time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been developed by combining a floor slab of an RC deck slab steel girder bridge to which a reinforcement structure by an under deck panel method is applied with an under deck panel by strength synthesis. It is an object of the present invention to provide a replaceable composite slab steel girder bridge which can be replaced at a low cost and in a short time with a highly stiff RC slab and a method of constructing the same.

[0011]

According to the present invention, there is provided a steel girder bridge with a composite floor slab, wherein a support plate member located along the lower surface of a reinforced concrete slab is joined to a steel girder. A reinforcing structure for supporting the plate by the steel girder via the support plate member is provided, and coupling means is provided on an upper surface of the support plate member so that the support plate member and the reinforced concrete slab can be combined with each other in strength. It is characterized by being combined.

Further, a reinforced concrete slab having a reinforcing structure in which a support plate member located along the lower surface of the reinforced concrete slab is connected to a steel girder and the reinforced concrete slab is supported by the steel girder via the support plate member. As a construction method for constructing a composite girder steel bridge by replacing the girder of the steel girder bridge, the reinforced concrete slab is removed, and after connecting means is arranged on the upper surface of the support plate member, concrete is removed. It is characterized in that the reinforced concrete floor slab is formed by being cast and combined with the support plate member.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of an RC floor slab steel girder bridge, which is an example of the construction of a recast composite slab steel girder bridge according to the present invention.
FIG. 2 is a longitudinal sectional view corresponding to the AA section. still,
FIG. 1 shows a substantially left half, and the right side edge in the figure is omitted. FIG. 3 shows an existing reinforced concrete slab steel girder bridge before the replacement of the floor slab in this configuration example, (A) is a cross section before reinforcement by the under deck panel method, and (B) is an under deck. It is a cross section after reinforcement construction by the panel method.

The illustrated RC slab steel girder bridge 10 is constructed by supporting a slab 12 made of reinforced concrete by main girder 11 extending in the direction of the bridge axis provided at predetermined intervals in a direction orthogonal to the bridge axis. The main girder 11 is supported and installed on a pier (not shown) via a bearing.

The main girder 11 has flanges of a predetermined width (upper flanges 11U, 11U) at upper and lower edges of a belly plate 11W having a predetermined height.
An I-shaped steel girder with a lower flange 11L),
The lower flange 11L is supported on the pier via a bearing.

The floor slab 12 is formed of reinforced concrete having a reinforcing bar 12A disposed therein, and is coupled to the main girder 11 by a dowel 11A planted on the upper surface of the upper flange 11U of the main girder 11 so as to transmit a shearing force. are doing. On the upper side, a pavement 14 of a predetermined thickness is formed by asphalt or the like.
Has been constructed.

An underdeck panel 20 as a support plate member is provided between the main girders 11 to provide a reinforcing structure by an underdeck panel construction method. A coupling structural member 30 is provided as coupling means, and the under deck panel 20 is coupled to the floor slab 12 by the coupling structural member 30 so as to be capable of synthesizing strength.

In the under deck panel 20, a plurality of longitudinal ribs 22 in the bridge axis direction are arranged at predetermined intervals in a direction perpendicular to the bridge axis on the lower surface side of a supporting steel plate 21 having a predetermined thickness.
Transverse ribs 23 orthogonal to the bridge axis are arranged at predetermined intervals in the bridge axis direction and are firmly formed.
It is fastened to the one abdominal plate 11W via a bracket 14 with a high-strength bolt and is firmly installed. In the figure, 15
Is a tilted structure erected between the main girders 11 and is disposed at predetermined intervals in the bridge axis direction. The length of the under deck panel 20 in the bridge axis direction is set so as not to interfere with the anti-tilt structure 15.

As shown in FIG. 4 (A) which is a partial plan view of the floor slab 12 excluding concrete, and FIG.
It is composed of a threaded dowel 31 of a predetermined length planted on the upper surface of the No. 0 supporting steel plate 21, and a reinforcing connection steel 32 fastened to the dowel 31 with a nut 33.

The dowel 31 is a shaft having a predetermined length with a screw formed at the tip thereof.
1 are planted in a row at the position where they should be arranged. Note that the planting position may be planted at a position other than the position where the reinforcing connection steel 32 is provided as required for the connection strength.

The reinforcing joint steel 32 is a Z-shaped cross-section in which flanges 32U and 32L having a predetermined width extend in opposite directions to upper and lower edges of a vertical abdominal plate 32W, respectively. 31 with penetrating flange 32L
The supporting steel plate 2 is fastened by a nut 33 screwed into the threaded end of the
1 is fastened and fixed to the upper surface. Its length is floor slab 12
Over the entire area in the width direction of the main girder 11, it reaches a side end projecting laterally from the support portion of the main girder 11, whereby a separate underdeck panel 20 positioned across the main girder 11 is provided.
Are connected via the reinforcing joint shaped steel 32.

When the connecting structural member 30 having the above-described configuration is immersed in the concrete of the floor slab 12, the under deck panel 20 fixed to the main girder 11 and the floor slab 12 are connected and integrated so as to be capable of synthesizing strength. It can be a rigid and highly durable synthetic floor slab. Since the reinforcing joint steel 32 is located inside the lower side of the floor slab 12 and reinforced in the direction orthogonal to the bridge axis, which is the longitudinal direction, the number of reinforcing bars in the relevant portion may be small. Since it reaches the side edge, the rigidity of the side protruding sideways from the main girder 11 can be improved.

Next, the existing RC floor slab steel girder bridge 1 shown in FIG.
By replacing the floor slab 12 'of 0', the RC girder bridge 1
The construction method for constructing No. 0 will be described.

First, the slab 12 'of the RC slab steel girder bridge 10' reinforced by the under-deck panel method shown in FIG. As shown, the under deck panel 20 and the main girder 11
Is left.

Next, as shown in FIG. 6, dowels 31 and 11A are implanted on the upper surface of the supporting steel plate 21 of the under deck panel 20 and the upper surface of the upper flange 11U of the main girder 11, and are erected on the under deck panel 20. As shown in the enlarged sectional views of FIGS. 7A and 7B, the reinforcing connection shaped steel 32 is fastened and fixed to the provided dowel 31 with the nut 33 to form the connecting structural member 30. After arranging the reinforcing bar 12A on the upper side of the upper flange 32U to obtain the state shown in FIG. 8, concrete is cast to form the floor slab 12, thereby completing the construction as shown in FIG. .

According to such a construction method, the under deck panel 20 functions as a formwork on the lower surface side at the time of placing concrete, so that it is not necessary to install a formwork, so that the construction time can be shortened. Is under deck panel 2
Since 0 is strength-combined with the floor slab 12, the rigidity is greatly improved as compared with before the replacement. For this reason, the floor slab 12 can be made thin and light (the dead load is small) with the same load resistance, and the load resistance can be increased with the same thickness.

It should be noted that the shape and the fixing structure of the reinforced joint steel as the joining means are not limited to the above-mentioned configuration examples, but can be changed as appropriate. Further, the reinforced joint steel is not necessarily used. In the above configuration example, a large number of dowels having a large diameter portion may be planted at the tip end similar to the dovetail 11A planted on the upper flange 11U of the main girder 11.

[0029]

As described above, according to the recast composite slab steel girder bridge according to the present invention, the support plate member located along the lower surface of the reinforced concrete slab is joined to the steel girder, and the reinforced concrete slab is reinforced. Is provided with a reinforcing structure for supporting the steel plate with a steel girder via a support plate member, a connecting means is provided on the upper surface of the support plate member, and the support plate member and the reinforced concrete slab are connected so as to be capable of strength synthesis. By having
The under deck panel and the floor slab fixed to the steel girder by the connecting means are combined and integrated so as to be capable of synthesizing strength, so that a composite slab with high rigidity and high durability can be obtained.

Further, a reinforced concrete floor slab steel girder bridge having a reinforcing structure in which a support plate member located along the lower surface of the reinforced concrete floor slab is connected to a steel girder and the reinforced concrete floor slab is supported by the steel girder via the support plate member. According to the construction method of constructing the composite girder bridge by replacing the slab of the slab, the reinforced concrete slab is removed, and after connecting means is provided on the upper surface of the support plate member, concrete is poured. By forming the reinforced concrete floor slab combined with the support plate member, the support plate member functions as a lower-side formwork when concrete is poured during construction of the reinforced concrete slab, which eliminates the need for formwork installation. Construction is possible and the construction period can be shortened. In addition, the rigidity of the support plate member is significantly improved after the construction since the support plate member is combined with the reinforced concrete floor slab in strength. Therefore, the reinforced concrete floor slab can be made thin and light with the same load capacity, and the load capacity can be increased with the same thickness.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a reinforced concrete slab steel girder bridge, which is an example of the configuration of a recast composite slab steel girder bridge according to the present invention.

FIG. 2 is a longitudinal sectional view corresponding to the AA sectional view.

3 (A) is a cross section of the RC deck slab girder bridge before reinforcement by the under deck panel method, and FIG. 3 (B) is a cross section after reinforcement by the under deck panel method.

FIG. 4A is a partial plan view of a floor slab excluding concrete, and FIG. 4B is a side view thereof.

FIG. 5 is a sectional view illustrating a construction step.

FIG. 6 is a sectional view illustrating a construction step.

FIG. 7 is a partial cross-sectional view illustrating an installation step of a coupling structural member.

FIG. 8 is a cross-sectional view illustrating a construction step.

FIG. 9 is a sectional perspective view of a bridge reinforced by a conventional underdeck panel method.

[Explanation of symbols]

 Reference Signs List 10 RC slab steel girder bridge (reinforced concrete slab steel girder bridge) 11 main girder 12 floor slab (reinforced concrete floor slab) 20 under deck panel (support plate member) 30 connection structural member (connection means)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeo Kasai 1-19-10 Mori, Koto-ku, Tokyo Ishikawajima-Harima Heavy Industries Co., Ltd. No. F-term in Ismic Co., Ltd. (Reference) 2D059 AA14 AA17 CC04 GG40 GG55

Claims (2)

[Claims] A support plate member positioned along a lower surface of the reinforced concrete floor slab is coupled to a steel girder, and a reinforcing structure for supporting the reinforced concrete floor slab by the steel girder via the support plate member is provided. A replaceable composite slab steel girder bridge, wherein coupling means is provided on an upper surface of the plate member, and the support plate member and the reinforced concrete slab are coupled so as to be capable of synthesizing strength. 2. A reinforced concrete slab having a reinforcing structure in which a support plate member located along the lower surface of the reinforced concrete slab is coupled to a steel girder and the reinforced concrete slab is supported by the steel girder via the support plate member. In the steel girder bridge, the reinforced concrete floor slab is removed, and after connecting means is provided on the upper surface of the support plate member, concrete is cast to form a reinforced concrete floor slab bonded to the support plate member. The construction method of the composite girder bridge to be replaced.