JP2002227131A - End section widening method for existing bridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an end section widening method for an existing bridge capable of expanding an end section in width for securing a right turn lane or the like, with the existing bridge kept in use. SOLUTION: An abutment section supporting the end section 1a of the existing bridge 1 is expanded to form an abutment expansion section 21, and an expansion lower chord 23 is suspended between the abutment expansion section 21 and the expansion base end section of the existing bridge 1. A truss expansion main truss 24 is provided between the expansion lower chord 23 and the existing bridge to connect them, then members 13 and 14 of the existing bridge becoming obstacles of traffic are removed. The work is mainly performed on the outside of the existing bridge, not on the existing bridge, and the existing bridge can be expanded in width while kept in use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for widening an end of an existing bridge, and more particularly to a method for widening a right-turn lane while using an existing bridge having one lane on each side, and is particularly applied to a lower truss bridge. It is preferable.

[0002]

2. Description of the Related Art For example, as shown in FIG. 3, there is only one lane on each side of an existing bridge which has been conventionally used, and if there is a vehicle 2 turning right from an end 1a of the bridge 1, the vehicle goes straight. There is a case where a vehicle or a vehicle turning left cannot pass and may cause a traffic jam.

In order to eliminate such traffic congestion on an existing bridge, it is necessary to replace the bridge. When a new bridge is to be built, a great deal of cost is required. If you try to use it, there is a problem that the existing bridge will be unusable during that time, and it is difficult to widen only the end part of the lower truss bridge, as shown in the example shown, because the entire truss will support the load. There's a problem.

On the other hand, as a method of repairing an existing bridge, for example, Japanese Patent Laid-Open Publication No. Hei 8-3937 discloses a method for widening a road under an overbridge such as an overpass or an overpass.
New piers are constructed at both ends of the existing bridge, and support structures such as arches or truss girders are erected between these piers.
It is disclosed that after connecting an existing main girder to this support structure, a pier or the like supporting the existing main girder is removed,
The existing main girder is effectively used to improve the workability and economic efficiency while renovating.

[0005]

However, such a method for repairing an existing bridge is a method for extending the existing bridge in the bridge axis direction, and cannot be directly applied to widening the existing bridge. Even if applied, support structures such as arches or truss girders must be erected along the existing main girder, and existing bridges cannot be repaired while in use, requiring long-term traffic suspension There is a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has a widened end which can secure a right turn lane or the like while using the existing bridge. It seeks to provide a way.

[0007]

According to a first aspect of the present invention, there is provided a method for widening an end of an existing bridge, the method comprising the steps of expanding an end of an existing bridge by at least one lane. An abutment supporting the end of the existing bridge can be supported corresponding to the widened portion, and a lower chord material for widening is bridged between the abutment capable of supporting the widened portion and the widened base end of the existing bridge. The present invention is characterized in that a reinforcing member is provided between the lower chord material for widening and the existing bridge to reinforce the member, and then the members of the existing bridge that hinder traffic are removed.

According to this method of widening the end of an existing bridge, when widening the end of the existing bridge by at least one lane, the abutment supporting the end of the existing bridge can be supported corresponding to the widened portion, A widening lower chord material is bridged between the abutment capable of supporting the widening portion and the widening base end of the existing bridge, and a reinforcing member is provided between the widening lower chord and the existing bridge to reinforce. After that, the members of the existing bridge that interfere with traffic are removed, so that the widened part can be supported by the abutment part of the existing bridge, and the lower chord material for widening is supported by this and reinforced with the reinforcing member By doing so, the work on the existing bridge is eliminated, and it is possible to widen the width in use.

According to a second aspect of the present invention, there is provided a method for widening an end of an existing bridge, wherein the abutment for supporting an end of the existing bridge is expanded to expand the abutment widening portion. It is characterized in that it can be constructed and supported corresponding to the widened portion.

According to this method of widening the end of an existing bridge, the abutment for supporting the end of the existing bridge is expanded to form an abutment widening portion, which can be supported corresponding to the widening portion.
By constructing an abutment widening part outside the existing bridge, supporting the lower chord material for widening and reinforcing it with reinforcing members, the work on the existing bridge can be eliminated and the widening can be performed as it is in use. ing.

According to a third aspect of the present invention, there is provided a method for widening an end of an existing bridge, wherein the existing bridge is a lower truss bridge and the reinforcing member is a truss structure. On the other hand, the bridge structure, vertical members and diagonal members of the lower truss bridge, which hinder traffic, are removed.

According to this method of widening the end of an existing bridge, the existing bridge is used as a lower truss bridge, and the reinforcing member is reinforced as a truss structure. The structure, vertical members and diagonal members are removed, and even if it is a lower truss bridge, the reinforcing members are truss structures so that the truss bridge can be widened.

According to a fourth aspect of the present invention, there is provided a method for widening an end portion of an existing bridge, wherein in addition to the configuration according to any one of the first to third aspects, a road surface at an end portion including the widened portion of the existing bridge is provided. It is characterized by comprising a steel deck.

According to this method of widening the end of an existing bridge, the road surface at the end including the widened portion of the existing bridge is made of a steel slab, and a dead load accompanying the widening is applied to a concrete slab or the like. We can make it smaller.

According to a fifth aspect of the present invention, there is provided a method for widening an end portion of an existing bridge, wherein the wide chord member and the reinforcing member are box-shaped in addition to any one of the first to fourth aspects. It is characterized by comprising a structural material.

According to this method of widening the end of an existing bridge, the lower chord material for widening and the reinforcing member are made of a box-shaped structural material so that the dead load accompanying widening is minimized. I have.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment in which the right-turn lane is widened by applying the method for widening the end of an existing bridge of the present invention to a lower truss bridge,
FIG. 1 is a schematic perspective view showing the first two steps, and FIG.
It is a schematic perspective view which shows a process.

The lower truss bridge 1 to which the end widening method of the existing bridge is applied is composed of, for example, a plat truss, and the main structure 10 includes a lower chord member 11, an upper chord member 12, and a diagonal member 13 connecting these members. The right and left main structures 1 are composed of vertical members 14.
0 are connected to each other by a bridge structure 15 and a floor girder 16 and an upper horizontal structure 17. Both ends of the lower truss bridge 1 are supported on the bridge seat of the abutment 18, respectively, and a pier is provided and supported at an intermediate portion according to the bridge length. As a road surface, for example, a concrete floor slab is used. Provided.

In order to widen the end of the lower truss bridge 1, that is, the bridge portion L that requires a right turn lane, FIG.
As shown in (a), the abutment 18 located at the leading end of the widening (the left end in the figure) is expanded by one lane and the abutment widening portion 21 is extended outward.
To build. The abutment widening portion 21 expanding to the outside may be either an integrated structure connected to the existing abutment 18 or an independent abutment widening portion 21 and has a structure capable of supporting the load of the lower truss bridge 20 after widening. I just want it.

If the abutment 18 itself has room to widen the lane and has a structure capable of supporting the widened portion without any problem in strength, the abutment 18 can be supported without constructing the abutment widened portion 21. An outer portion or the like may be used.

After the abutment widening portion 21 is constructed at the widening end portion in this way, as shown in FIG. 1B, the branch girder 22 is projected outward from the lower chord material 11 of the lower truss bridge 1 serving as the widening base end. Then, the lower chord member 23 for widening is bridged between the branch girder 22 and the outer end of the abutment widening portion 21.

Next, on this widening lower chord material 23, FIG.
As shown in (a), the widening diagonal member 25 and the widening vertical member 26 are connected as reinforcing members constituting the widening main structure 24 which is the main structure of the widening truss, and the widening upper chord member 27 is connected. Then, the widening main structure 24 is constructed.

The widening main structure 24 may be used for transporting and installing components assembled in advance in a factory or the like, or may be used for assembling blocks or individual members on site. What is necessary is just to select according to the situation of a spot, etc.

After the widening main structure 24 is thus constructed,
To connect with the main structure 10 of the adjacent existing bridge 1, FIG.
As shown in (b), the floor girder 16 is extended to extend the floor girder 2 for widening.
8 and the bridge structure 29 for widening and the upper horizontal structure 30 for widening.

After the widening main structure 24 is connected in this manner,
Depending on the shape of the diagonal member 13 and the vertical member 14 of the main structure 10 in the central part, which obstructs traffic, and also the shape of the bridge structure 15, a part obstructing traffic is removed by cutting or the like.

Thereafter, the road surface at the end 1a including the widened portion is replaced with the conventional concrete slab, and the steel slab 31 is used.
The dead load increase accompanying the widening is suppressed as much as possible.

In the widened lower truss bridge 20, a right turn lane can be provided with one side of the end 1a as two lanes, and congestion due to a right turn vehicle can be prevented.

According to the method for widening the end of the existing bridge, there is almost no need to work on the existing bridge 1 during construction of the widening main structure 24, and work outside is performed, so that traffic is cut off. There is almost no need to expand the width in use.

Further, the number of members for widening is small, and the cost can be significantly reduced as compared with the replacement of a bridge.

Furthermore, the abutment widening portion 21 can be easily constructed by minimizing the increase in its own weight due to the widening of the road surface of the entire end including the widened portion as the steel floor slab 31.

The members constituting the widening portion, for example, the main structure 24 for widening, the floor girder 28 for widening, the bridge structure 29 for widening, and the upper horizontal structure 30 for widening are formed of a box-shaped structural material instead of a solid material. By doing so, it is possible to reduce the weight while securing the required strength,
The dead load can be further reduced.

In the above embodiment, the case where the present invention is applied to a lower truss bridge has been described. However, the present invention is not limited to this and can be applied to an existing bridge having another structure.

[0033]

According to the method for widening the end of an existing bridge according to the first aspect of the present invention, the end of the existing bridge is widened by at least one lane. At this time, the abutment supporting the end of the existing bridge can be supported corresponding to the widened portion, and a lower chord material for widening is provided between the abutment capable of supporting the widened portion and the widened base end of the existing bridge. After bridging and providing a reinforcing member between the lower chord for widening and the existing bridge to reinforce, the members of the existing bridge that hinder traffic are removed, so that the abutment portion of the existing bridge is used. The widened portion can be supported, and the widened lower chord material is supported on the widened portion and reinforced with the reinforcing member, so that the work on the existing bridge can be eliminated, and the widened portion can be widened in a used state.

According to the method for widening the end of an existing bridge according to a second aspect of the present invention, the abutment supporting the end of the existing bridge is expanded to form an abutment widening part, and the widening part is constructed. Since it was possible to support it, an abutment widening part was constructed outside the existing bridge, and the lower chord material for widening was supported on it and reinforced with reinforcing members, eliminating work on the existing bridge and using it It can be widened as it is.

Further, according to the method for widening the end of an existing bridge according to a third aspect of the present invention, the existing bridge is a lower truss bridge, and the reinforcing member is reinforced by a truss structure.
The truss bridge and the vertical and diagonal members of the lower truss bridge, which are obstacles to traffic, are removed. It can be widened while keeping it.

According to the method for widening the end of an existing bridge according to a fourth aspect of the present invention, since the road surface at the end including the widened portion of the existing bridge is formed of a steel deck, The accompanying dead load can be reduced as compared with a concrete slab or the like.

Further, according to the method for widening the end of an existing bridge according to claim 5 of the present invention, the lower chord material for widening and the reinforcing member are formed of a box-shaped structural material. Dead load can be minimized.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing the first two steps according to an embodiment of widening a right turn lane by applying an end widening method of an existing bridge according to the present invention to a lower truss bridge.

FIG. 2 is a schematic perspective view showing the latter two steps according to an embodiment in the case where the method for widening the end of an existing bridge of the present invention is applied to a lower truss bridge to widen a right-turn lane.

FIG. 3 is a schematic front view of an existing bridge to which the present invention is applied and a schematic plan view of a road surface.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower truss bridge 1a End part 10 Main structure 11 Lower chord material 12 Upper chord material 13 Diagonal material 14 Vertical material 15 Bridge gate 16 Floor girder 17 Upper horizontal structure 18 Abutment 20 Lower truss bridge after widening 21 Abutment widening part 22 Branch Girder 23 Wider lower chord material 24 Widening main structure 25 Wider diagonal material 26 Wider vertical material 27 Wider upper chord material 28 Wider floor girder 29 Wider bridge structure 30 Wider upper horizontal structure 31 Steel slab L Widening required Part (end)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mamoru Sugisaki 5-30-13, Toyo, Koto-ku, Tokyo F-term in Ismic Co., Ltd. 2D059 AA01 BB33 GG39 GG55

Claims (5)

[Claims] When widening the end of an existing bridge by at least one lane, an abutment supporting the end of the existing bridge can be supported corresponding to the widened portion, and an abutment capable of supporting the widened portion is provided. After extending the lower chord material for widening between the base end of the widening of the existing bridge and providing a reinforcing member between the lower chord material for widening and the existing bridge, the existing bridge which becomes a hindrance to traffic is provided. A method for widening an end of an existing bridge, wherein a member of the bridge is removed. 2. The existing bridge according to claim 1, wherein the abutment supporting the end of the existing bridge is expanded to form an abutment widened portion and can be supported corresponding to the widened portion. End widening method. 3. The existing bridge is a lower truss bridge, and the reinforcing member is reinforced by a truss structure, while removing a bridge structure, a vertical member, and a diagonal member of the lower truss bridge that hinder traffic. 3. The method for widening an end of an existing bridge according to claim 1, wherein the width of the end is increased. 4. The method for widening an end of an existing bridge according to claim 1, wherein the road surface at the end including the widened portion of the existing bridge is formed of a steel slab. 5. The method of widening an end of an existing bridge according to claim 1, wherein the lower chord material for widening and the reinforcing member are formed of a box-shaped structural material.