JPH1113148A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a buckling phenomenon by forming a space section in the axial-center direction of an elastic protective body. in which rubber layers and steel plates are bonded alternately, and fitting an elastic supporter, in which the rubber layers and the steel plates are bonded alternately, into the space section. SOLUTION: The base isolation device 1 is formed of a cylindrical-body shaped elastic protective body 2 and an elastic supporter 3 fitted to the elastic protective body 2, and the base isolation device 1 is installed between a foundation 4 and an upper building frame 5. The elastic protective body 2 is formed in protective body units divided into four, a space section 7 penetrated in the axial-center direction of a central section is narrowed and formed gradually towards the lower side, and a laminate 10, in which rubber layers and steel plates are superposed alternately, is bonded with a substrate 11 and the inside of a Joint plate 12. The elastic supporter 3 fitted into the space section 7 of the elastic protective body 2 is formed of the circular rubber layers 16 and the circular steel plates 17 in a laminated shape, and an upper end plate 18 and a lower end plate 19 larger than the rubber layers 16 are set up onto a top face and an underside and connected by bolts. Accordingly, the elastic supporter forcibly displaced at the time of an earthquake is brought into contact with the internal surface of the space section, and a buckling phenomenon can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation device interposed between an upper frame of a building and a foundation for preventing vibration energy such as a large earthquake from being transmitted to the building.

[0002]

2. Description of the Related Art Since Japan is an earthquake country, many damages have been caused by earthquakes, and particularly damage to buildings and the like has caused a great loss. Therefore, as a countermeasure against building earthquakes, improvements have been made such as strengthening the frame, but in recent years, seismic isolation devices have been developed instead of these to prevent the vibration energy of the earthquake from being transmitted to the building.

In this seismic isolation device, an elastic support 33 having a rubber layer 31 and a steel plate 32 alternately bonded thereto has a large diameter or a small diameter as shown in FIGS. Board 3
4 and a lower end plate 35, which are interposed between the foundation 36 and the upper frame 37 of the building.

[0004]

However, among the above seismic isolation devices, those having a small diameter of (2) have a secondary shape factor (a value obtained by excluding the diameter by the total rubber thickness: the larger the value, the higher the stability). When the horizontal displacement increased due to a large horizontal force due to a large earthquake, there was a possibility that the load on the upper frame could not be fully supported and a buckling phenomenon might occur.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a seismic isolation device having a small secondary shape factor, which receives a large horizontal force due to a large earthquake or the like and causes a large horizontal displacement. In this case, the buckling phenomenon is not caused by bearing the load of the upper frame.

[0006]

According to the seismic isolation device of the present invention for solving the above-mentioned problems, a space is formed in an axial direction of an elastic protective body in which a rubber layer and a steel plate are alternately bonded,
An elastic support in which a rubber layer and a steel plate are alternately bonded is fitted into the space.

In the seismic isolation device of the present invention, the elastic protective body is also forcibly displaced in the horizontal direction along with the forcible displacement of the elastic support in the horizontal direction due to vibration energy during an earthquake. At this time, the elastic support that has been forcibly displaced comes into contact with the inner surface of the space of the elastic protector, increasing the diameter of the elastic support, supporting the load of the upper frame via the contact surface and eliminating the buckling phenomenon. I do.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the seismic isolation device of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of the seismic isolation device of the present invention, and FIG. 2 is a perspective view of an elastic protective body.

A seismic isolation device 1 is composed of a cylindrical elastic protective body 2 and an elastic support 3 fitted into the elastic protective body 2, and as shown in FIG. 5 to reduce the force applied to the upper skeleton 5 during an earthquake.

The elastic protector 2 is formed by joining protective unit 6 divided into four parts, and a space 7 penetrating in the axial direction at the center gradually narrows downward.
The protective body unit 6 is formed by bonding a laminate 10 in which a quarter-circle rubber layer 8 and a quarter-circle steel plate 9 are alternately laminated to each other in a frame 13 of a substrate 11 and a joining plate 12. I have. Accordingly, the cylindrical elastic protective body 2 as shown in FIG. 2 is formed by bolting the protective body unit 6 with the bonding plate 12.

As shown in FIG. 1B, the front surface of the bonding plate 12 is located outside the inner surface of the laminate 10 and the substrate 11 is located slightly outside the inner surface of the laminate 10. A gap 14 for inserting the lower end plate of the elastic support 3 to be inserted is secured.

The elastic support 3 fitted in the space 7 of the elastic protective body 2 has a circular rubber layer 16 and a circular steel plate 1.
7 are alternately overlapped to form a laminated shape, and the upper and lower surfaces of the upper end plate 18 and the lower end plate 1 larger than the rubber layer 16 are formed on the upper and lower surfaces.
9 are provided respectively. The upper end plate 18 is joined to the upper skeleton 5 and the lower end plate 19 is joined to the foundation 4 by bolts, so that the elastic support 3 is attached between the foundation 4 and the upper skeleton 5 to support the upper skeleton 5. doing.

Therefore, when a relative displacement in the horizontal direction occurs between the foundation 4 and the upper skeleton 5 due to a large earthquake, the elastic support 3 between the foundation 4 and the upper skeleton 5 is forcibly displaced as shown in FIG. When the displacement exceeds a certain level, the elastic protective body 2 is also forcibly displaced in the horizontal direction, and the elastic support 3 and the elastic protective body 2 integrally support the upper frame 5. This integration is realized by the forcedly displaced elastic support 3 coming into contact with the inner surface of the space 7 of the elastic protective body 2, and the diameter of the elastic support 3 is increased to eliminate the buckling phenomenon.

The elastic protector 2 includes the elastic support 3
Is installed between the foundation 4 and the upper frame 5, and then the protective unit 6 is combined so as to surround the elastic support 3. In addition, the elastic protective body 2 is not fixed to the foundation 4 in principle, but may be bolted with a fixing tool 20 as shown in FIG. In addition, the elastic protective body 2 is not limited to four divisions, may be a half division, or may be formed integrally without division.

[0015]

According to the present invention, the elastic protective body is forcibly displaced in the horizontal direction along with the forcible displacement of the elastic support in the horizontal direction due to vibration energy during an earthquake. The elastic support that has been forcibly displaced at this time
By contacting the inner surface of the space portion of the elastic protection body, the diameter of the elastic support body is increased to support the load of the upper frame, thereby eliminating the buckling phenomenon.

[Brief description of the drawings]

1 is a sectional view of a seismic isolation device of the present invention, and (2) and (3) are partially omitted sectional views of the seismic isolation device.

FIG. 2 is a perspective view of the seismic isolation device.

FIG. 3 is a cross-sectional view of the seismic isolation device horizontally displaced.

FIG. 4 is a front view of a conventional seismic isolation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seismic isolation device 2 Elastic protective body 3 Elastic support 4 Foundation 5 Upper frame 6 Protector unit 7 Space 8 Rubber layer 9, 17 Steel plate 18 Upper plate 19 Lower plate

Claims (4)

[Claims] 1. A space is formed in the axial direction of an elastic protector in which a rubber layer and a steel plate are alternately bonded, and an elastic support in which a rubber layer and a steel plate are bonded alternately is fitted into the space. A seismic isolation device characterized by the following. 2. The seismic isolation device according to claim 1, wherein the elastic support is sandwiched between an upper end plate and a lower end plate, and is interposed between an upper skeleton and a foundation. 3. The seismic isolation device according to claim 1, wherein the space portion of the elastic protective body is formed so as to penetrate in the axial direction and to be gradually narrowed downward. 4. The elastic protective body is formed by connecting a plurality of divided protective body units.
Seismic isolation device described in.