JP5878657B1 - Bridge slab support structure and floor slab replacement method - Google Patents

Abstract

The present invention provides a bridge slab support structure and a floor slab replacement method capable of performing a work for replacing a reinforced concrete slab laid on a bridge with a steel slab in as short a time as possible. A floor slab support bracket (5) is attached above a web (3b) of a main girder (3), and a concrete floor slab is removed leaving a portion on an upper flange (3a) as a residual portion (4). The steel slab 2 having the horizontal ribs 21, the vertical ribs 22 and the deck plate 20 is placed on the floor slab support bracket 5 and joined to the removed portion. The road surface 7 is formed by paving the upper surface of the deck plate 20. [Selection] Figure 1

Description

  The present invention relates to a floor slab support structure in the case of replacing a reinforced concrete floor slab constituting a bridge with a steel floor slab and a floor slab replacement method related to this structure.

  For example, the Metropolitan Expressway is one of the roads functioning as a traffic artery in the Tokyo metropolitan area. One of the purposes of the construction of the Metropolitan Expressway is the smooth transport of athletes and passengers between the Olympic Village, Haneda Airport, accommodation facilities and each competition venue during the Tokyo Olympics held in 1964. There is a road that has been completed at that time, and a considerable period has passed since construction. In particular, depending on the degree of damage, such as cracks or peeling off, in the reinforced concrete floor slab, it is necessary to replace the floor slab without repair. In 2020, the Olympic and Paralympic Games are scheduled to be held again in Tokyo. To ensure the safety of transporting athletes and passengers, replacement work for the floor slabs of aging roads is required. The need for is increasing.

  On the other hand, when replacing a reinforced concrete slab, it is desired to replace it with a steel slab in order to improve durability without increasing the weight of the slab. Since steel slabs are lighter than reinforced concrete slabs, they are often applied to replacement work for reinforced concrete slabs under traffic conditions.

  In the replacement work of the floor slab, for example, the reinforced concrete floor slab is removed from the main girder, and the steel slab is placed in place of the reinforced concrete floor slab and newly installed. However, the main girder and the reinforced concrete slab are synthesized by a gibber fixed to the upper flange of the main girder. Therefore, when removing the reinforced concrete slab, the concrete around the jibli must be removed by lifting work. Cost. On the other hand, since it is necessary to block the traffic during the replacement work of the floor slab, it is desired that the replacement work shortens the work time for blocking the traffic as much as possible. However, since the above-described suspension work takes time, there is a limit to shortening the time for blocking traffic.

  In addition, in order to shorten the traffic interruption time and to replace the reinforced concrete floor slab in a short period of time, the bridge reinforced concrete floor slab that had to be repaired was disassembled with the gibber on the main girder flange left. Subsequently, a steel floor slab having a connecting rib capable of locking the rectangular space is placed on the flange, concrete is poured into the rectangular space, and solidified to form the main girder and the steel floor slab. An overhanging method for a bridge reinforced concrete floor slab that has been integrated has been proposed (see Patent Document 1).

  In addition, in the bridge reinforced concrete slab replacement method in which the reinforced concrete floor slab in the range divided in the direction of the bridge axis is sequentially replaced with the steel slab, when dismantling and removing the reinforced concrete slab in the divided range, In the work on one day, the reinforced concrete floor slab located on the main girder is allowed to remain in the required width in a comb shape, and the remaining part is disassembled and removed on the next work day. There has been proposed a bridge reinforced concrete slab rehabilitation method in which steel slabs that are sequentially blocked are joined on the main girder (see Patent Document 2).

JP-A-60-59210 JP-A 62-45805

  In the invention disclosed in Patent Document 1, it is necessary to partially hang the reinforced concrete on the flange of the main girder and remove the gibber. Since this work takes time, there is a limit to shortening the time for traffic interruption.

  In addition, in the invention disclosed in Patent Document 2, by adjusting the amount of work per day, it is possible to shorten the time of traffic interruption, but since work is divided and repeated work is performed, eventually There is a risk that the construction period will be longer.

  By the way, most of the metropolitan expressway is laid by elevated bridges. In the case of this type of bridge, depending on the content of the work, the work may be performed from below the road. Therefore, the present invention provides a bridge floor slab support structure and a floor slab that enable the work from the bottom of the bridge to be performed when the reinforced concrete floor slab is replaced with a steel floor slab, thereby shortening the time to block traffic as much as possible. The purpose is to provide a replacement method.

As a technical means for achieving the above object, a bridge slab support structure according to the present invention comprises a reinforced concrete floor slab for replacing a reinforced concrete floor slab supported by a main girder of a bridge with a steel slab. In the floor slab support structure of the bridge for arranging the steel slab at the position where the slab is removed, a floor slab support bracket attached to the main girder at an appropriate interval below the reinforced concrete floor slab, A part of the reinforced concrete floor slab other than the upper flange part of the main girder is removed, and a remaining part of the reinforced concrete floor slab remaining on the upper flange part and a removed part from which the reinforced concrete floor slab is removed consists of a disposed steel deck, the steel slab is especially that it comprises a transverse rib which avoids the residual portion, is attached to the transverse ribs in the floor plate support bracket It is set to.

  By joining the horizontal ribs of the steel slab to the floor slab support bracket, the existing main girder and the new steel slab are connected to each other. In addition, the steel slab is replaced with the portion where the existing reinforced concrete slab except the residual portion was installed, and the horizontal rib is arranged, and the deck plate on the upper side of the horizontal rib covers the residual portion. Arranged. The removal of the reinforced concrete floor slab is performed by cutting the remaining portion.

  That is, the lateral rib has a discontinuous structure at a position corresponding to the remaining portion. The lateral rib is stiffened by the floor slab support bracket and the deck plate.

  Then, the deck surface is paved with asphalt or the like to form a road surface. Also, the height of the road surface is adjusted by adjusting the thickness of the asphalt.

Further, the bridge slab support structure according to the invention of claim 2 is characterized in that a filler is injected into a gap between the deck plate of the steel slab and the residual portion.

  When the steel plate slab is attached to the floor slab support bracket and the deck plate is in contact with the upper surface of the residual portion, the load due to traffic of the automobile and the like can be supported in this residual portion. When a gap is formed in the deck plate, the gap is filled with a filler.

  According to a third aspect of the present invention, there is provided a method for replacing a floor slab of a bridge in a position where the reinforced concrete floor slab is removed in order to replace the reinforced concrete floor slab supported by the main girder of the bridge with a steel floor slab. In the method of replacing a floor slab of a bridge in which a steel slab is arranged, a floor slab support bracket is attached to the main girder at an appropriate interval below the reinforced concrete slab, and is positioned on the upper flange of the main girder. Other parts except for the reinforced concrete floor slab are removed to provide a residual portion in the upper flange portion of the main girder, and in place of the removed reinforced concrete floor slab, there are lateral ribs arranged to avoid the residual portion. The lateral rib of the steel slab is arranged, and the lateral rib is attached to the floor slab support bracket.

  That is, the floor slab support bracket is attached to the main girder from below the bridge. The work at this time can be performed without blocking traffic. In addition, the floor slab support bracket to be attached is disposed at an appropriate interval in a sufficient number to support the steel slab in the bridge axis direction. Next, the traffic is interrupted, and the remaining part of the reinforced concrete slab is removed while leaving the remaining portion. That is, both sides of the remaining portion are cut along the bridge axis direction. Thereby, a residual part remains and a reinforced concrete floor slab is removed. Next, a steel floor slab manufactured in advance at a factory or the like is placed on the floor slab support bracket on the part from which the reinforced concrete floor slab has been removed, and is joined to the floor slab support bracket by, for example, bolting or the like. .

  Thereafter, the upper surface of the deck plate of the disposed steel deck is paved with asphalt or the like to form a road surface.

  In the bridge floor slab replacement method according to the invention of claim 4, after the steel floor slab is placed on the floor slab bracket, a filler is injected into a gap between the steel floor slab and the residual portion. It is characterized by doing.

  When a gap is formed between the deck plate and the remaining portion in a state where the steel deck is installed, the gap is filled with a filler such as an epoxy resin. This filler is injected from an injection port formed in advance in a steel deck or the like.

  According to the bridge slab support structure and the floor slab replacement method according to the present invention, the work of attaching the floor slab support bracket to the upper part of the main girder can be performed from below the bridge, so that traffic is blocked. Can be done without. Further, when removing the reinforced concrete floor slab, it is not necessary to pick up the concrete around the dowel, so that the time required for the removal work can be shortened. For this reason, the reinforced concrete slab can be efficiently replaced with a steel slab, and the time for blocking traffic can be shortened as much as possible.

It is a figure which shows the floor slab support structure of the bridge | bridging concerning this invention, and is sectional drawing cut | disconnected by the surface orthogonal to the bridge-axis direction of a bridge. It is sectional drawing which expands and shows the principal part of the floor slab support structure of the bridge concerning this invention. It is an AA arrow line view in FIG. It is sectional drawing cut | disconnected and shown along the BB line in FIG. It is a figure explaining the procedure which replaces the floor slab of a bridge from a reinforced concrete floor slab by a method concerning this invention from a steel slab.

  Hereinafter, a bridge slab support structure and a floor slab replacement method according to the present invention will be described based on the illustrated preferred embodiments.

  FIG. 1 shows a state in which a steel slab 2 is laid in place of the reinforced concrete slab of the bridge 1 by this replacement method. The steel slab 2 is constructed by joining a deck plate 20 to a horizontal rib 21 arranged in a direction perpendicular to the bridge axis and a vertical rib 22 arranged in the bridge axis direction. A side string 23 is joined to the end of the bridge 1 in the direction perpendicular to the bridge axis. On the upper surface of the upper flange 3a of the main girder 3 of the bridge, a part of the existing reinforced concrete floor slab is left as a residual portion 4. On the upper part of the web 3b of the main girder 3, a floor slab support bracket 5 having a mounting portion 5a protruding in a direction perpendicular to the bridge axis is attached. The floor slab support bracket 5 is fixed to the web 3b by welding, bolting or the like. The mounting portion 5a is protruded laterally from the end portion of the remaining portion 4 in the direction perpendicular to the bridge axis. In addition, the portion of the existing reinforced concrete floor slab 10 (see FIG. 5) that becomes the remaining portion 4 is formed by cutting the reinforced concrete floor slab 10 along the bridge axis direction and leaving the residual portion 4. That is, the remaining portion 4 is a part of the existing reinforced concrete floor slab 10, and this remaining portion 4 is joined to the gibber 6 planted on the upper flange 3a, and the concrete around the gibber 6 is suspended. The structure is not necessary. Further, the lateral rib 21 is discontinuous in the remaining portion 4.

  In the removal portion 10a (shown in FIG. 5 (b)) from which the existing reinforced concrete floor slab 10 has been removed, the end portion of the lateral rib 21 is placed on the placement portion 5a of the floor slab support bracket 5 attached to the main girder 3. Is placed and the steel floor slab 2 is provided. The horizontal rib 21 of the steel slab 2 and the floor slab support bracket 5 are joined by welding, bolting or the like.

  A road surface 7 is formed by paving with asphalt or the like on the upper surface of the deck plate 20 connecting the upper portions of the lateral ribs 21 attached to the floor slab support bracket 5.

  Next, a floor slab replacement method for replacing the existing reinforced concrete floor slab 10 with the steel floor slab 2 using this support structure will be described.

  As shown in FIG. 5A, the floor slab support bracket 5 is attached to the web 3b of the main girder 3 of the existing bridge. Since this operation can be performed below the bridge, it can be performed without blocking traffic. Next, a part of the reinforced concrete floor slab 10 indicated by an imaginary line in FIG. 5B is removed. That is, the remaining portion 4 and the removal portion 10a are cut and the reinforced concrete floor slab 10 other than the remaining portion 4 is removed. The horizontal rib 21 of the steel slab 2 is placed on the removed portion 10a of the removed reinforced concrete floor slab 10, and the end of the horizontal rib 21 is placed on the floor slab support bracket 5 as shown in FIG. 5 (c). The steel slab 2 and the floor slab support bracket 2 are joined by being placed on and supported by the part 5a and welding or bolting.

  The top surface of the deck plate 20 of the steel slab 2 supported by the floor slab support bracket 5 is paved with asphalt or the like, and the state shown in FIG. 1 is obtained. The operation of removing the removal portion 10a of the reinforced concrete slab 10 can be performed in a state where one-way traffic is allowed by blocking one-way traffic on the road.

  Incidentally, in the state in which the steel deck 2 is installed, a slight gap G may be formed in the deck plate 20 of the steel deck 2 and the residual portion 4 as shown in FIG. In this case, the gap G is filled with a filler such as an epoxy resin. In this case, the filler can be injected by providing an inlet in the steel deck 2. Then, the road surface 7 is paved.

  According to the bridge slab support structure and the floor slab replacement method according to the present invention, it is possible to shorten the period of traffic interruption in the work of replacing the reinforced concrete slab with the steel slab, and to reduce the traffic volume such as at night. Since replacement work of floor slabs can be done in a short time, the social impact due to traffic interruption can be reduced as much as possible, and it can contribute to road repair and life extension reasonably.

1 Bridge 2 Steel deck
20 Deck plate
21 Horizontal rib
22 Vertical rib
23 Side girder 3 Main girder
3a Upper flange 4 Remaining part 5 Floor slab support bracket
5a Place 6 Giber 7 Road surface
10 Reinforced concrete slab
10a Removal part G Gap

Claims (4)

In order to replace the reinforced concrete slab supported by the main girder of the bridge with the steel slab, in the bridge slab support structure for placing the steel slab in the position where the reinforced concrete slab is removed,
Under the reinforced concrete floor slab, a floor slab support bracket attached to the main girder at an appropriate interval;
Removing a portion of the reinforced concrete floor slab other than the upper flange portion of the main girder, and a remaining portion of the reinforced concrete floor slab remaining on the upper flange portion;
It consists of a steel slab arranged in the removal part from which the reinforced concrete slab is removed,
The steel deck is provided with a lateral rib that avoids the residual portion,
A bridge floor slab support structure, wherein the lateral rib is attached to the floor slab support bracket. The bridge floor slab support structure according to claim 1, wherein a filler is injected into a gap between the deck plate of the steel floor slab and the residual portion. In order to replace the reinforced concrete slab supported by the main girder of the bridge with the steel slab, in the bridge slab replacement method of arranging the steel slab in the position where the reinforced concrete slab is removed,
Below the reinforced concrete floor slab, attach a floor slab support bracket to the main girder at an appropriate interval,
Removing the other parts except the reinforced concrete floor slab of the part located on the upper flange of the main girder to provide a residual part on the upper flange part of the main girder,
In place of the removed reinforced concrete slab, the horizontal rib of a steel slab having a horizontal rib arranged to avoid the residual portion is arranged, and the horizontal rib is attached to the floor slab support bracket, How to replace floor slabs of bridges.   The bridge floor according to claim 3, wherein after the steel deck is placed on the deck bracket, a filler is injected into a gap between the deck plate of the steel deck and the residual portion. Version replacement method.

Images