JPS6115049Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to rubber bearings used for bridges, elevated structures, etc., and particularly to rubber bearings that are capable of absorbing excessive horizontal forces such as those caused by earthquakes.

Conventionally, rubber bearings used for bridges, elevated structures, etc. support the load acting on superstructures such as bridge girders, and furthermore, in order to release the expansion, contraction and tilting of the superstructure, rubber elastic bodies layered with reinforcing plates are attached to the upper part. Either the rubber support can be placed directly between the structure and the lower structure such as a pier, or the upper shoe can be fixed to the upper structure and the lower shoe can be fixed to the lower structure, and a rubber elastic body can be placed between the upper and lower shoes. Some methods have been adopted, such as supporting it.

If an excessive horizontal force such as an earthquake is applied to the rubber bearing alone, the rubber elastic body is likely to be damaged by the horizontal force by exceeding the allowable deformation value of the rubber elastic body. In addition to the rubber bearing, an embodiment is used in which an anchor bar or a shock absorber for restraining or absorbing horizontal force is provided between the upper and lower structures.

However, in this embodiment, since a rubber bearing and an anchor bar or a shock absorbing device are installed together,
By securing space for these, the lower structure becomes larger than necessary.

In general, many bridges and viaducts that use rubber bearings are relatively small, and by providing installation space for the rubber bearings and anchor bars or shock absorbers in the lower structure, the size of the lower structure increases beyond the required size for installation. There is a problem that the balance of the structure of the parts is lost and the manufacturing cost increases.

The present invention has been made in view of these circumstances. That is, in a rubber bearing that includes an upper shoe that is fixed to an upper structure such as a bridge, a lower shoe that is fixed to a lower structure such as a pier, and a rubber elastic body layered with a reinforcing plate between the upper and lower shoes, A bearing pressure hole is formed in the center of the upper shoe, and a through hole that matches the bearing pressure hole of the upper shoe is formed in the center of the rubber elastic body.

A damping beam having one end fixed to the center of the lower shoe and a head having a curved side surface at the other end is installed in the upper shoe and the bearing pressure hole and through hole of the rubber elastic body. To provide a rubber bearing characterized in that the head is positioned in a bearing pressure hole of an upper shoe.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is an anchor bolt 2 to the substructure B such as a bridge pier
...lower shoe fixed by 2 etc., 3 upper shoe fixed to superstructure G such as a bridge girder by anchor bolt 4...4 etc., 5 rubber layered with reinforcing plate 6...6 It is an elastic body.

7 is a bearing pressure hole provided in the center of the upper shoe 3; 8 is a through hole provided in the center of the rubber elastic body 5; the center of the through hole 8 is aligned with the bearing pressure hole 7. .

Reference numeral 9 denotes a damping beam fixed to one end of the center portion of the lower shoe 1 by welding or the like, and the damping beam 9 has a head 10 having a curved side surface at the other end.

The damping beam 9 is arranged in the through hole 8 of the rubber elastic body and the bearing pressure hole 7 of the upper shoe, with the side peripheral surface of the head 10 being positioned so as to be in contact with the inner wall of the bearing pressure hole 7. There is.

11 is the upper structure G in the bearing hole 7 provided in the upper shoe 3.
This is a cover that covers the upper end of the bearing pressure hole 7 to prevent concrete and the like from entering.

Next, the operation of the rubber bearing of the present invention will be explained with reference to FIG.

In other words, an excessive horizontal force such as an earthquake causes the damping beam 9 to be moved by the horizontal force to the bearing hole 7 of the upper shoe.
The damping beam 9 is brought into contact with the damping beam 9 and elastically deformed to absorb the damping beam.

Note that even when the damping beam 9 is elastically deformed,
The contact between the bearing pressure hole 7 of the upper shoe and the damping beam 9 is carried out smoothly by the sliding contact between the curved head 10 side peripheral surface of the damping beam and the inner wall of the bearing pressure hole 7. be.

In addition, the normal expansion, contraction and inclination of the upper structure G are followed by the deformation of the rubber elastic body 5, which causes the damping beam 9 to come into contact with the bearing pressure hole 7 of the upper shoe and undergo minute elastic deformation during expansion and contraction. When tilting, the inner wall of the bearing hole 7 and the head 10 form a curved surface of the damping beam.
By sliding the side circumferential surfaces, it is made to follow and be allowed.

By configuring the rubber bearing in this way,
Normal expansion, contraction and inclination of the superstructure G can be tolerated by the deformation of the rubber elastic body 5, and excessive horizontal forces such as those caused by earthquakes are absorbed by the elastic deformation of the damping beam 9. Because it can restrain deformation beyond a certain amount, damage caused by excessive deformation can be prevented.

FIG. 5 shows a rubber bearing according to another embodiment.

That is, in this embodiment, a flange portion 12 that narrows inwardly is provided at the lower end of the bearing pressure hole 7 of the upper shoe, and the head portion 10 of the damping beam engages with the flange portion 12 in the vertical direction at a constant interval. In particular, when the upper structure G is lifted up, the flange portion 12 and the head 10 of the damping beam are engaged to restrain the lifting up.

Note that similar effects can be obtained in this embodiment as well.

In this embodiment, the head 10 of the damping beam is placed in contact with the inner wall of the bearing pressure hole 7 of the upper shoe, and when normal expansion/contraction and tilting of the upper structure G are allowed by deformation of the rubber elastic body 5, In the explanation, the damping beam 9 is made to follow by micro-elastic deformation when expanding or contracting, and the head 10 is made to slide into contact with the bearing pressure hole 7 when tilting, but as the amount of expansion and contraction of the upper structure G becomes large, the damping beam Since the amount of elastic deformation of the beam 9 becomes large and the expansion and contraction is inhibited by the resistance, it is also possible to provide a gap commensurate with the amount of expansion and contraction between the bearing hole 7 and the head 10 of the damping beam in advance. It is.

Note that even in this case, there is no problem in allowing the tilt.

The present invention has the above-mentioned configuration, and by providing a damping beam within the rubber bearing to absorb excessive horizontal forces such as those caused by earthquakes, it is possible to reduce the installation space on the substructure compared to the conventional joint installation method. This has great practical effects, such as being able to prevent damage caused by excessive deformation of the bearing and further reducing manufacturing costs.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing the rubber bearing of the present invention, Fig. 2 is a partially longitudinal front view thereof, and Fig. 3 is:
FIG. 4 is a partial cross-sectional plan view of the same, FIG. 4 is an explanatory view of the operation of the rubber bearing of the present invention, and FIG. 5 is a vertical cross-sectional side view showing the rubber bearing of another embodiment. 1: lower shoe, 3: upper shoe, 5: rubber elastic body, 6: reinforcing plate, 7: bearing hole, 8: through hole, 9: damping beam, 10: head.

Claims (1)

[Scope of claim for utility model registration] (1) An upper shoe fixed to a superstructure such as a bridge girder, a lower shoe fixed to a lower structure such as a bridge pier, and a rubber elastic body layered with a reinforcing plate between the upper and lower shoes. In the rubber bearing, a bearing pressure hole is formed in the center of the upper shoe, and a through hole that matches the bearing pressure hole of the upper shoe is formed in the center of the rubber elastic body. A damping beam, which has one end fixed to the center of the lower shoe and a head whose side surface is curved at the other end, is installed in the bearing pressure hole and through hole of the shoe and the rubber elastic body. A rubber bearing characterized by being arranged in a bearing hole of a shoe. (2) A flange portion narrowing inwardly is provided at the lower end of the bearing pressure hole of the upper shoe, and the damping beam is fitted so that the head of the damping beam engages with the flange portion in the vertical direction at a constant interval. A rubber bearing according to claim (1) of the utility model registration, characterized in that the head is positioned in a bearing pressure hole.