JPH08158308A - Expansion joint for bridge - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an expansion joint for bridges in which an anchor member is not easily damaged. [Structure] Anchor members 1 and 1 embedded in adjacent bridge girders H, H, a pedestal 2 screwed to the anchor members 1 and 1, respectively, and screws in a manner of being bridged to the pedestals 2 and 2. An expansion joint for a bridge having a stretchable elastic surface layer elastic body 3 and a bridge plate H bridged between the bridge girders H, H to receive a load on the surface elastic layer body 3,
Each cradle 2 is composed of separate steel upper / lower plates 20 and 21 and an elastic member 22 interposed between the upper and lower plates 20 and 21, and the anchor member 1 has a lower plate. 21 and the surface elastic body 3 are screwed to the upper plate 20, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bridge expansion joint.

[0002]

2. Description of the Related Art As an expansion joint of this type, there is, for example, one shown in FIG. This expansion joint is basically, as shown in FIG. 3, anchor members 90, 90 embedded in adjacent bridge girders H, H, and a U-shaped cross section screwed to the anchor members 90, 90. Cradle 91,
It has an expandable and contractible surface rubber body 92 laid between the pedestals 91, 91, and a receiving plate 93 laid over a lower plate 91b of the pedestal 91 to receive a load on the surface rubber body 92. The upper plate portion 91a of the pedestal 91 and the surface rubber body 92 are attached to the anchor member 90 and the lower plate portion 91b of the pedestal 91.
Are fixed with screws.

Therefore, even if the bridge girders H, H and the bridge pier are expanded or contracted due to changes in atmospheric temperature, or the bridge girders H,
Even if a step or the like between H occurs, these will not be
It can be absorbed by the expansion and contraction of the surface rubber body 92 received at.

However, in the expansion joint, the tensile / compressive force due to the expansion and contraction of the surface rubber body 92, the load acting on the surface rubber body 92 and the like are directly passed through the pedestal 91 (usually made of steel). The anchor members 90, 90 act on the anchor members 90, 90, and as a result, the anchor members 90, 90 are damaged in a relatively short period of time. Incidentally, the replacement work of the anchor members 90, 90 is very troublesome because it requires chipping work of concrete, and therefore,
In this type of industry, it is desired to develop an expansion joint in which the anchor member is not damaged for a long period of time.

[0005]

Therefore, an object of the present invention is to provide an expansion joint for bridges in which an anchor member is less likely to be damaged.

[0006]

According to the present invention, anchor members 1 and 1 embedded in adjacent bridge girders H and H, respectively, and a pedestal 2 screwed to the anchor members 1 and 1, respectively.
And a stretchable surface elastic body 3 screwed in a manner to bridge the pedestals 2 and 2, and a receiving plate bridged between the bridge girders H to receive the load on the surface elastic body 3. An expansion joint for bridge having 4 and 4, wherein each pedestal 2 is made of separate steel upper / lower plates 20, 21 and said upper / lower plates 20, 21.
It is composed of an elastic material 22 interposed between each other,
The anchor member 1 has a lower plate 21, and the upper plate 20 has a surface elastic body 3.
However, each is screwed.

[0007]

The present invention operates as follows.

The tensile / compressive force due to the expansion and contraction of the surface elastic body 3, the load acting on the surface elastic body 3, and the like are transmitted to the anchor member 1 through the route of the upper plate 20 → the elastic material 22 → the lower plate 21. However, since the upper and lower plates 20 and 21 are separated, the tensile / compressive force and load are absorbed by the elastic material 22,
A large force does not act on the anchor member 1.

Therefore, in the expansion joint of the present invention, the anchor member 1 is less likely to be damaged as compared with the one described in the section of the conventional art.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described with reference to the drawings shown as embodiments.

Basically, the expansion joint for bridge of this embodiment, as shown in FIGS. 1 and 2, has anchor members 1, 1 embedded in adjacent bridge girders H, H and the anchor members 1, 1, respectively. 1, a pedestal 2 screwed to the pedestal 1, and a stretchable surface elastic body 3 screwed in a manner of bridging the pedestals 2 and 2.
And the bridge girders H, H to receive the load on the surface elastic body 3.
It is composed of a receiving plate 4 which is bridged between them.

As shown in FIG. 1, the anchor member 1 is constructed by welding an anchor bolt 11 to an anchor nut 10 and is fixed by welding to a reinforcing bar h embedded in a bridge girder H.

As shown in FIGS. 1 and 2, the pedestal 2 includes an upper plate 20 made of a steel plate and a lower plate 21 made of a steel plate and having a width about three times as wide as the upper plate 20. And the upper and lower plates 20 are formed to have a width about twice that of the upper plate 20,
21 and an elastic material 22 interposed between them, and these are integrated by an adhesive material. Further, as shown in FIG. 1, a hard elastic material 5 (rubber, urethane, polyester, nylon, etc.) having a relatively wide width and a large radius of curvature is provided on the upper surface of each of the lower plates 21 and 21 on the facing side. Can be used) is fixed. The cap nut 22b is fixed to the upper plate 20 in a manner of being embedded in the elastic member 22, and the through hole 22a is formed in the elastic member 22 portion protruding from the upper plate 20 in a top view. The pedestal 2 is bolt B3 as shown in FIG.
It is screwed to the anchor nut 10.

As shown in FIGS. 1 and 2, the surface layer elastic body 3 is made of thick band-shaped rubber having a constant width (other elastomers such as resin can be used), and is provided on both sides. A thin portion 30 that is slightly wider than the plate 20 is formed, and a steel plate 31 is fixed to the lower surface of the thin portion 30. Further, as shown in FIG. 1 and FIG. 2, the thin portion 30 is formed with an elongated through hole 30a for accommodating the head of the bolt B1, and the steel plate 31 portion corresponding to the thin portion 30 has a bolt. A long hole 31a into which the male screw portion of B1 is inserted is formed, and a through hole 30b whose constituent wall is formed of a steel plate is formed in the middle of the surface elastic body 3 in the width direction. Further, as shown in FIGS. 1 and 2, this surface elastic body is provided with a thin groove 30c on its upper surface so that it can expand and contract in the width and length directions.
And a large number of large holes 30d are formed on the lower surface.

As shown in FIGS. 1 and 2, the receiving plate 4 has a screw hole 41 (a hole into which the hexagon socket head cap screw B2 is screwed when integrated with the surface layer elastic body 3) in the middle of the width direction. It is made of thick steel plate.

When the expansion joints of this embodiment are installed on adjacent bridge girders, the following steps (1) to (2) are carried out (see FIG. 1). Put the bridge girders H, H on the upper side of the butted part, and rebar h
To bury. The anchor bolt 11 of the anchor member 1 is welded to the reinforcing bar h. The lower plate 21 of the pedestal 2 is screwed onto the anchor nut 10 with the bolt B3. The surface elastic body 3 integrated with the receiving plate 4 with the hexagon socket head bolt B2 is screwed to the upper plate 20 of the receiving base 2 with the bolt B1.

Here, in the installed state of the expansion joint, the tension / compression force due to the expansion and contraction of the surface elastic body 3, and the surface elastic body 3 are provided.
The load acting on the bolt B1 → upper plate 20 → elastic material 2
Although it is transmitted to the anchor member 1 through the route of 2 → lower plate 21 → bolt B3, since the upper / lower plates 20 and 21 are separated from each other, the tensile / compression force and the load are elastic to the elastic member 22. The anchor member 1 is absorbed by the deformation, and a large force does not act on the anchor member 1. Therefore, the anchor member 1 will not be damaged in a short period of time.

[0018]

The present invention having the above-mentioned structure has the following effects.

From the contents described in the above operation, it is an object to provide an expansion joint for bridges in which the anchor member is not easily damaged.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a bridge expansion joint according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the bridge expansion joint.

FIG. 3 is a cross-sectional view of a conventional expansion joint for bridges.

[Explanation of symbols]

 H Bridge girder h Reinforcing bar 1 Anchor member 2 Cradle 3 Surface elastic body 4 Catch plate 10 Anchor nut 11 Anchor bolt 20 Upper plate 21 Lower plate 22 Elastic material

Claims (1)

[Claims] 1. An anchor member (1) (1) embedded in an adjacent bridge girder (H) (H), and a pedestal (2) screwed to the anchor member (1) (1), respectively. ,
A stretchable surface elastic body (3) screwed in a manner of being bridged over the cradle (2) (2), and the surface elastic body (3)
Expansion joint for a bridge having a bridge plate (4) bridged between the bridge girders (H) (H) to receive a load on the bridge,
Each cradle (2) has separate steel upper and lower plates (20) (2
1) and an elastic material (22) interposed between the upper and lower plates (20) and (21), and the lower plate (21) is attached to the anchor member (1) and the upper plate (20). ) The expansion joints for bridges, characterized in that the surface elastic bodies (3) are respectively screwed to them.