JPH08218321A - Bearing structure with movement limiter in horizontal direction of bridge - Google Patents

Abstract

PURPOSE: To expand/contract and rotate a bridge girder smoothly owing to load, a temperature change and creeping, and to limit amount of horizontal movement more than a valve set by design calculation. CONSTITUTION: First and second vertical plates 7 are mounted on an upper shoe 5 placed on the top face of a rubber shoe 2. The first and second vertical plates 7 are faced oppositely while forming clearances to the end faces of the rubber shoe 2, and the rubber shoe 2 is made easy to the displaced in the horizontal direction and brought into contact until the first and second vertical plates 7 are brought into contact with the end faces of the rubber shoe 2, thus increasing the spring constant of the rubber shoe 2, and then preventing displacement in the horizontal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support structure with a horizontal movement restricting device for supporting a bridge girder on a pier or abutment.

[0002]

2. Description of the Related Art In simple girder type or continuous girder type bridges, conventionally, steel or rubber bearing structures have been used for vertical loads, and generally fixed bridges for horizontal forces. Supported. In recent years, a new type of bridge, which is a type of continuous girder type called horizontal reaction force distribution structure, has been constructed. In these bridges, expansion and contraction of girders due to temperature changes, earthquake loads, etc. are absorbed by the movable bearing structure.
Usually, these movement amounts are obtained by design calculation, and the possible movement amount of the bearing structure is set accordingly. In addition, if the amount of movement of the girder exceeds the possible amount of movement of the bearing structure due to earthquake motion that is larger than the designed earthquake, a movement restriction device or a bridge prevention device is provided to prevent excessive movement of the girder.

[0003]

In recent years, a rubber bearing structure has been widely used because of its running property, corrosion resistance, and its applicability to the horizontal reaction force dispersion structure. . On the other hand, in bridges, it is necessary to support the bridge girder on the pier / abutment so that it can expand and contract smoothly and rotate due to loading, temperature changes, and creep. The bridge girder direction of the bridge girder (the lengthwise axis of the bridge) , The amount of movement in the direction perpendicular to the bridge axis is set by design calculation.

For this reason, the spring constant of the rubber shoe is set to a value that is displaced in the horizontal direction by an amount corresponding to the amount of movement set by the design calculation, so that a large horizontal load is applied due to an earthquake or the like. At times, the rubber shoe may be largely displaced in the horizontal direction, and the bridge girder may be moved by an amount larger than the movement amount set by the design calculation, causing the bridge girder to drop and collide with the bridge girder. The spring constant of the rubber dregs is the product of the shear modulus of the rubber dregs and the horizontal area of the rubber dregs divided by the height of the rubber dregs.

To solve this problem, the spring constant of the rubber shavings should be increased to reduce the horizontal displacement. However, if this is done, the bridge girder movement set by the above-mentioned design calculation cannot be obtained. Due to loading, temperature change, and creep, the bridge girder cannot be expanded / contracted / rotated smoothly with respect to the pier / abutment, which may cause damage to the bridge girder.

Further, in order to increase the spring constant of the rubber shoe, the shear elastic modulus is increased, the horizontal area is increased, and the height is decreased, so that the shear elastic coefficient is increased or the height is decreased. Then, the function of supporting the vertical load and the function of absorbing kinetic energy are deteriorated, which is not preferable as a seismic isolation device. If the horizontal area is increased, a large installation space is required, and the installation may not be possible on a relatively narrow pier.

For this reason, in the case of a rubber bearing structure, generally, a movement restricting device and a bridge preventing device are attached separately from the bearing body, but in this case, in order to arrange these facilities, they are mounted on the pier or abutment. A large space is required, and in some cases, the size of the pier or abutment top end is determined for this reason, which may be uneconomical. Also, in order to attach the movement restriction device or the bridge prevention device to the pier, it is necessary to attach anchor bolts to these devices and embed them in the pier or abutment.
Construction becomes complicated.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a bearing structure with a horizontal movement restricting device for a bridge that can solve the above-mentioned problems.

[0009]

SUMMARY OF THE INVENTION A support structure with a horizontal movement restricting device for a bridge according to the present invention has a rubber trough 2 and a plate-shaped member 6 placed on the rubber trough 2 and an end surface of the rubber trough 2. The upper shoe 5 is provided with vertical plates 7 facing each other with a gap.

[0010]

[Operation] The vertical plate of the upper shoe 5 placed on the rubber shoe 2 moves horizontally with a small horizontal load until it comes into contact with the end surface of the rubber shoe 2, and when the vertical plate comes into contact with the end surface of the rubber shoe 2, the spring constant becomes Increases limit horizontal movement.

[0011]

[Example] As shown in FIG. 1, a rubber shoe 2 is provided on an upper surface 1a of a pier 1, and the rubber shoe 2 has a rectangular planar shape and a reinforcing plate 4 embedded in a rubber body 3 having a predetermined thickness. It supports vertical loads and absorbs kinetic energy.

An upper shoe 5 is placed on the upper surface of the rubber shoe 2, and the upper shoe 5 is placed on a plate-like body 6 as shown in FIGS. 1 and 2.
A pair of first vertical plates 7 and 7 facing each other and a pair of second vertical plates 8 and 8 facing each other are fixed and reinforced by a retaining plate 9. The first vertical plates 7 and 7 are rubber shavings. 2 are opposed to both end surfaces 2a, 2a perpendicular to the bridge axis direction X in FIG. 2 with a gap t ₁ therebetween, and the second vertical plate 8 has a clearance t ₂ with both end surfaces 2b, 2b in the rubber shaft 2 in the bridge axis direction X. Facing each other, and the first and second vertical plates 7,
The lower end of 8 has substantially the same height as the reinforcing plate 4, and the bridge girder 10 is placed on the plate-shaped body 6.

The spring constant of the rubber trough 2 is a value that is displaced in the horizontal direction when a small horizontal load is applied to the bridge girder 10, and the gaps t ₁ and t ₂ are perpendicular to the bridge axis direction X set by design calculation. The value is equal to or slightly larger than the movement amount in the direction (hereinafter referred to as the Y-axis direction Y) and the movement amount in the bridge-axis direction X (that is, substantially equal).

Because of this, the bridge girder 10 moves in the direction Y at right angles to the bridge axis and the direction X (all horizontal directions) in the bridge axis by a small horizontal load, and the bridge girder 10 is moved relative to the pier 1 due to loading, temperature change, and creep. It can be expanded and contracted and rotated smoothly.

Further, when a large horizontal load F acts on the bridge girder 10 in the direction Y perpendicular to the bridge axis, the first vertical plate 7 abuts on the end face 2a of the rubber trough 2 which is perpendicular to the bridge axis direction X, as shown in FIG. The rubber shoe 2 undergoes shear deformation S and the rubber shoe 2
The height of is reduced from H ₁ to H ₂ (H ₁ > H ₂ ) and the spring constant is increased, making it difficult for the rubber shoe 2 to be displaced in the horizontal direction, limiting horizontal movement in the direction perpendicular to the bridge axis, Limit the horizontal movement in the direction Y perpendicular to the bridge axis that exceeds the movement amount set in the design calculation.

The rubber shoe 2 has a rubber body 3 and a reinforcing plate 4
Since the lower ends of the reinforcing plate 4 and the vertical plate 7 are substantially the same height, the reinforcing plate 4 can also limit the horizontal movement,
Even if the shear elastic modulus of the rubber body 3 is increased so that the kinetic energy in the vertical direction can be sufficiently absorbed,
The horizontal movement amount of can be reduced.

When a large horizontal load F acts on the bridge girder 10 in the bridge axis direction X, the second vertical plate 8 causes horizontal movement in the bridge axis direction X which is larger than the amount of movement set in the design calculation as described above. Restrict.

FIGS. 4 and 5 show a concrete use state, in which a pair of first concrete pedestals 11 and 11 are provided at intervals on the upper surface 1a of the pier 1 in the direction X and the direction Y perpendicular to the bridge axis,
A second concrete pedestal 12 is provided between the pair of first concrete pedestals 11 and 11, and the bearing structure A of the present invention is provided on the pair of first concrete pedestals 11 and 11, respectively, and the second concrete pedestal 12 is provided. A horizontal return position B is provided across the bridge girder 10.

The horizontal return position B is the anchor bar 20 embedded in the second concrete pedestal 12 as shown in FIG.
And a shock absorber 21 provided in a recess 10a formed on the lower surface of the bridge girder 10, and the shock absorber 21 is an outer cylinder 22,
An inner cylindrical body 24 having an anchor bar insertion hole 23 into which the protruding portion of the anchor bar 20 is fitted, and an inner peripheral surface of the outer cylindrical body 22 and an outer peripheral surface of the inner cylindrical body 24 are substantially radially integrated. It is composed of a plurality of connecting pieces 25 provided in a specific manner.

Because of this, after the horizontal movement in the bridge axis direction X and the bridge axis orthogonal direction Y, the horizontal return device B returns to the original position.

Next, a second embodiment will be described. As shown in FIG. 7, only a pair of first vertical plates 7, 7 are provided on the plate-like body 6 with a gap between both end surfaces 2a, 2a of the rubber shoe 2 which are perpendicular to the bridge axis direction X to form the upper shoe 5. is there.

In this case, the movement of the bridge girder 10 is restricted by the amount of movement set by the design calculation in the direction Y perpendicular to the bridge axis, and the movement in the bridge axis direction X is not restricted. In the case of such a bridge, the seismic isolation device shown in FIG. 7 may be used because the amount of movement set by the design calculation in the bridge axis direction X is large and connected to the direction X so as to be relatively displaceable.

Next, a third embodiment will be described. As shown in FIG. 8, the rubber shoe 2 has a plane circular shape, and the first and second vertical plates 7 and 8 have a continuous plane circular ring shape.

In each of the above embodiments, the plate-shaped body 6 of the upper shoe 5 and the first and second vertical plates 7 and 8 are separate bodies, but one plate material is bent as shown in FIG. Plate 6 and first
-The second vertical plates 7 and 8 may be integrated.

[0025]

EFFECT OF THE INVENTION Until the vertical plate of the upper shoe 5 placed on the rubber shoe 2 hits the end face of the rubber shoe 2, the bridge girder moves horizontally with a small horizontal load, and the vertical plate comes to the end face of the rubber shoe 2. If it hits, the spring constant becomes large and the horizontal movement of the bridge girder is restricted. Therefore, the bridge girder can be expanded and contracted and rotated smoothly due to loading, temperature change, creep, etc., and it is possible to prevent the bridge girder from moving and dropping more than the set amount set by the design calculation, and to prevent the bridge girders from colliding with each other. 2
It is preferable as a seismic isolation device because it has sufficient functions to absorb vertical load and absorb kinetic energy without the need to increase the shear modulus of elasticity more than necessary or to reduce the height, and further increase the horizontal area more than necessary. There is no need to make it large, the installation space is small, and it can be installed on a relatively narrow pier.

Further, since it is not necessary to install a movement restricting device or a bridge preventing device, a wide space is not required for the pier or the abutment top end, and anchor bolts are not required, which facilitates the construction.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is an explanatory diagram of a horizontal movement amount regulating operation.

FIG. 4 is a front view showing a specific use state.

FIG. 5 is a plan view of FIG.

FIG. 6 is a plan view of a horizontal return position.

FIG. 7 is a plan view showing a second embodiment of the present invention.

FIG. 8 is a plan view showing a third embodiment of the present invention.

FIG. 9 is a perspective view showing a second embodiment of the upper shoe.

[Explanation of symbols]

1 ... Bridge pier, 2 ... Rubber shaving, 2a ... End face in the direction perpendicular to the bridge axis, 3 ...
Rubber body, 4 ... Reinforcing plate, 5 ... Upper shoe, 6 ... Plate-shaped body, 7
... 1st vertical plate, 8 ... 2nd vertical plate, 10 ... Bridge girder.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Shiratani 1-25-1 Nishi Shinjuku, Shinjuku-ku, Tokyo Within Shinjuku Center Building Taisei Corporation (72) Inventor Takaji Fukui 2-9 Mure, Mitaka City, Tokyo No. 17 (72) Inventor Nobuo Iwabuchi 3-105, Sugaya, Ageo City, Saitama Prefecture Fukoku Co., Ltd.

Claims (3)

[Claims] 1. A horizontal bridge structure comprising a rubber shoe 2 and an upper shoe 5 provided with a plate 6 placed on the rubber shoe 2 and a vertical plate facing the end face of the rubber shoe 2 with a gap therebetween. Bearing structure with movement restriction device. 2. The support structure with a horizontal movement restricting device for a bridge according to claim 1, wherein the gap between the end face of the rubber shoe 2 and the vertical plate is substantially equal to the amount of movement of the bridge girder set by design calculation. 3. A horizontal movement of a bridge according to claim 1, wherein a reinforcing plate 4 is embedded in the rubber body 3 to form a rubber trough 2, and the lower ends of the reinforcing plate 4 and the vertical plate have substantially the same height. Bearing structure with a limiting device.