JPH10176308A - Structure of lead contained laminated rubber support - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a function for a long period of time by burying a horizontally deformable cylindrical constraining member on a rubber layer in the circumference of a lead plug enclosed in the vertical direction in a laminated rubber main body. SOLUTION: A laminated rubber support 1 is constituted by enclosing a lead plug 7 in an enclosing hole 8 provided on a central part of a columnar laminated rubber main body 6 and burying a coil spring 13 on a rubber layer part in the circumference of the hole 8. At the time of an earthquake, when upper and lower part structures 4, 5 are relatively displaced in the horizontal direction, the main body 6 carries out base isolating work by lengthening an input cycle by its elastic characteristics, the plug 7 absorbs vibrational energy by plastically shearing and deforming itself and damping work is carried out. Additionally, the spring 13 synchronizes with extension of the main body 6 in the horizontal direction and extends and constrains the plug 7 by surrounding it. Consequently, even when the support repeatedly receives shearing deformation, biting of reinforcing plates 10, 11, 12 into the plug 7 and biting of the plug 7 into the rubber layer are prevented. Accordingly, it is possible to maintain an expected energy absorbing characteristics for a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a laminated rubber bearing containing lead, and more particularly, to a structure in which a lead plug is sealed in a laminated rubber body to support a load and to reduce vibration energy such as an earthquake. The present invention relates to a structure of a seismic isolation bearing device that absorbs by utilizing shear deformation of a floor.

[0002]

2. Description of the Related Art Conventionally, a lead-containing laminated rubber bearing in which a lead plug is sealed in a laminated rubber body in which a rubber layer and a reinforcing plate are alternately laminated in the vertical direction, has a function of reducing vibration energy during an earthquake. It is widely known as an absorbing and damping seismic isolation bearing device. The lead plugs used in this laminated rubber bearing exhibit energy absorption characteristics by causing shear deformation along with horizontal deformation of the laminated rubber body when the upper structure and lower structure undergo relative displacement during an earthquake. It is.

However, when the laminated rubber bearing is repeatedly subjected to shear deformation, the reinforcing plate, usually made of a steel plate, in the laminated rubber main body cuts into the lead plug, the lead plug itself cuts into the rubber layer, and furthermore, the lead plug is locally damaged. Harmful deformation such as deformation may occur. As a result, the desired energy absorption characteristics may not be obtained.

[0004]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects.

An object of the present invention is to prevent the above-mentioned reinforcing plate from biting into the lead plug, biting into the rubber layer of the lead plug, and preventing harmful deformation such as local deformation of the lead plug. An object of the present invention is to provide a structure of a lead-containing laminated rubber bearing capable of obtaining desired energy absorption characteristics over a long period of time.

[0006]

The present invention employs the following means to achieve the above object.

That is, the present invention relates to a lead-containing laminated rubber bearing in which a lead plug is vertically enclosed in a laminated rubber body in which a rubber layer and a reinforcing plate are alternately laminated in a vertical direction. The present invention provides a structure of a lead-containing laminated rubber bearing, wherein a horizontally deformable cylindrical restraining member is buried in a rubber layer surrounding the rubber layer.

Further, the present invention provides a structure of a lead-containing laminated rubber bearing, wherein the restraining member is a coil spring.

The laminated rubber bearing is installed between the upper structure and the lower structure, and the load of the upper structure is transmitted to the lower structure via the laminated rubber body. When an oscillating force is applied to the lower structure during an earthquake, the upper and lower structures are relatively displaced in the horizontal direction, and the laminated rubber body undergoes elastic shear deformation. Is transmitted to the upper structure by prolonging the period, and performs seismic isolation.
On the other hand, the lead plug also undergoes plastic shear deformation along with the shear deformation of the laminated rubber main body, and absorbs vibration energy by the plastic deformation to perform a damping action.

According to the present invention, when the laminated rubber body is sheared as described above, the restraining member is also deformed in the horizontal direction following the shear deformation, and the lead plug is constantly restrained by the restraining member surrounding the lead plug. Therefore, even if the laminated rubber bearing is repeatedly subjected to shear deformation, it is possible to prevent the reinforcing plate from biting into the lead plug and the lead plug itself from biting into the rubber layer.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing the structure of a lead-containing laminated rubber bearing according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG. The laminated rubber bearing 1 is installed between the upper structure 4 and the lower structure 5 via the upper mounting plate 2 and the lower mounting plate 3. Here, the lower structure 5 is, for example, a concrete foundation constructed on the ground, and the upper structure 4 is a middle-to-high-rise building.

The laminated rubber bearing 1 has a laminated rubber body 6 having a columnar shape as a whole, and a circular sealing hole 8 for sealing a lead plug 7 is formed in the center thereof. The main body 6 is formed by alternately stacking an annular rubber layer 9 and reinforcing plates, that is, thick upper and lower reinforcing plates 10 and 11 and a thin intermediate reinforcing plate 12. , 11, and 12 are integrated by vulcanization adhesion.
The reinforcing plates 10, 11, and 12 are members for restraining the swelling of the laminated rubber when the load of the upper structure 4 is received, thereby preventing the laminated rubber bearing 1 from being compressed and deformed.

A coil spring 13 is embedded in the rubber layer around the sealing hole 8 so as to surround the lead plug 7. This coil spring 13
Are installed without load in the tension and compression directions. The coil spring 13 is made of durable spring steel, but may be made of reinforced fiber.

The laminated rubber body 6 provided with the coil spring 13 is generally manufactured as follows. That is, an annular rubber layer 9 having an inner diameter larger than the sealing hole 8 and reinforcing plates 10, 11, and 12 are laminated in a molding die. As a result, a hole 14 having a larger diameter than the sealing hole 8 is formed at the center of the laminate. On the other hand, a hollow cylindrical rubber body in which the coil spring 13 is embedded is separately formed, and this is
At the time of molding, and vulcanized and bonded.

The lead plug 7 has a cylindrical shape, and is press-fitted into the sealing hole 8 of the laminated rubber body 6. At this time, since the rubber layer around the sealing hole 8 is restrained by the coil spring 13, the sealing hole 8 does not expand.

The upper and lower mounting plates 2 and 3 are made of a disk-shaped steel plate and have a bottomed boss hole 15 at the center. A bottomed boss hole 16 is also formed at the center of the upper and lower reinforcing plates 10 and 11 of the laminated rubber body 6, and a shear key 17 is fitted into these boss holes 15 and 16. The upper and lower reinforcing plates 10 and 11 are provided with a plurality of bolt holes 18.
The laminated rubber main body 6 and the upper and lower mounting plates 2 and 3 are integrally connected by mounting bolts 19 screwed to the mounting member 8. A plurality of bolt holes 20 are formed in the upper and lower mounting plates 2, 3, and the upper and lower mounting plates 2 are mounted on the upper and lower structures 4, 5 via anchor bolts 21 screwed into these bolt holes 20. Can be

Next, the operation of the lead-containing laminated rubber bearing 1 will be described with reference to FIG. The load of the upper structure 4 is transmitted to the lower structure 5 via the laminated rubber body 6. When the vibration force F is input to the lower structure 5 during an earthquake, the upper and lower structures 4, 5 are relatively displaced in the horizontal direction, and the laminated rubber body 6 undergoes elastic shear deformation. Due to its elastic characteristics, the input period is lengthened and transmitted to the upper structure 4 to perform seismic isolation. On the other hand, the lead plug 7 also undergoes plastic shear deformation along with the shear deformation of the laminated rubber main body 6, and absorbs vibration energy by the plastic deformation to perform a damping action.

During the above-described shear deformation of the laminated rubber main body 6, the coil spring 13 also deforms in the horizontal direction following the shear deformation. At this time, the coil spring 13
Elongates in synchronism with the horizontal elongation of the laminated rubber body 6,
As a result, the coil spring 13 always surrounds the lead plug 7 over its entire length. That is, the lead plug 7 is always constrained by the coil spring 13, so that even if the laminated rubber bearing 1 is repeatedly subjected to shear deformation, the reinforcing plates 10, 11, 12
Of the lead plug 7 and the rubber layer of the lead plug 7 itself are prevented.

Further, during the shear deformation of the laminated rubber body 6, the coil spring 13 transmits the horizontal force caused by the horizontal movement of the intermediate reinforcing plate 12 to the lead plug 7 evenly in the longitudinal direction. Therefore, harmful deformation such as local deformation can be prevented from occurring in the lead plug 7. From the above, the laminated rubber bearing 1 exhibits the expected energy characteristics even if it is repeatedly subjected to a shearing action for a long period of time.

FIG. 5 is a longitudinal sectional view showing another embodiment, and FIG. 6 is a sectional view taken along line BB of FIG. In this embodiment, the laminated rubber main body 6 is formed in a quadrangular prism shape as a whole, and a plurality of lead plugs 7 are formed.
Is provided. A coil spring 13 is embedded in a rubber layer around each lead plug 7. In addition, the same reference numerals are given to the same members as those in the above embodiment, and the description is omitted. The lead-containing laminated rubber bearing 1 of this embodiment is:
For example, the superstructure is used for supporting a bridge which is a bridge girder and the lower structure is a pier or an abutment.

[0021]

As described above, according to the present invention, even if the laminated rubber bearing is repeatedly subjected to shear deformation, the reinforcing plate does not bite into the lead plug, the lead plug bites into the rubber layer,
It is possible to prevent harmful deformation such as local deformation of the lead plug from occurring, and to obtain desired energy absorption characteristics over a long period of time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is an operation explanatory view.

FIG. 4 is a longitudinal sectional view showing another embodiment.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lead-containing laminated rubber bearing 4 ... Upper structure 5 ... Lower structure 6 ... Laminated rubber main body 7 ... Lead plug 8 ... Enclosure hole 9 ... Rubber layer 10 ... Upper reinforcing plate 11 ... Lower reinforcing plate 12 ... Intermediate reinforcing plate 13 … Coil spring 17… Shear key

Claims (2)

[Claims] 1. A lead-containing laminated rubber bearing in which a lead plug is vertically enclosed in a laminated rubber body in which a rubber layer and a reinforcing plate are alternately laminated in a vertical direction. A structure of a lead-containing laminated rubber bearing, wherein a horizontally deformable cylindrical restraining member is embedded in a rubber layer. 2. The structure of a lead-containing laminated rubber bearing according to claim 1, wherein said restraining member is a coil spring.