JPH0516516B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a system for supporting structures that are installed between bridges, buildings, and other various structures and the underlying foundation ground, and for transmitting power to the structure. This invention relates to a seismic isolation device for reducing earthquake motion.

[Conventional technology and its problems]

Conventionally, as a seismic isolation device for various structures, seismic isolation supports made of synthetic rubber reinforced with laminated steel plates have been installed between the structure and the underlying foundation, but this has not been effective in damping vibrations. I can't expect much,
When a large seismic force is applied from the ground, deformation becomes large and there is a problem in terms of strength.

Therefore, in recent years, seismic isolation devices for structures have been made of elastic bodies such as synthetic rubber reinforced with steel plates.
And, by using two types of supports: an elastic support that supports the structure and is capable of horizontal movement, and a support that does not support the structure and is formed by a leaf spring made of stacked elastic bodies with high friction damping. A system has been proposed to prevent excessive shaking of structures during earthquakes (Japanese Patent Laid-Open No. 189463/1983).

However, even in this case, in the elastic support that supports the structure, only the elastic material such as synthetic rubber reinforced by laminated steel plates bears the weight of the structure, so There is a problem with durability due to the large load acting on the elastic body, and even if two types of supports are used as mentioned above,
After long-term use, the elastic force of the elastic support decreases, resulting in a decrease in the seismic isolation effect.

In view of the above, the present invention provides a seismic isolation system for structures that can effectively attenuate seismic motion during earthquakes, stably support the structure, have excellent durability, and exhibit good seismic isolation effects over a long period of time. The aim is to provide equipment.

[Means for solving problems]

The present invention is a seismic isolation device that is installed between a structure and the foundation ground below to support the structure, and which provides elastic support between an upper fixing plate on the structure side and a lower fixing plate on the ground side. In particular, in order to solve the above-mentioned problems, an elastic support body is formed by further spirally winding a long elastic coil.
Alternatively, it is characterized in that a plurality of wound spring bodies are placed sideways and embedded inside an elastic body such as synthetic rubber.

[Effect]

According to the above seismic isolation device of the present invention, when seismic force is transmitted from the ground to the elastic support during an earthquake, the elastic body such as synthetic rubber and the coiled spring body inside the elastic support are It deforms elastically to absorb and reduce the seismic energy of an earthquake.

In particular, the wound spring body of the elastic support body is made by further spirally winding an elastic coil, and has a double coil shape and is in a sideways state. has a large elastic force, which can prevent excessive elastic deformation of the elastic support. In addition, since this coiled spring body is embedded inside an elastic body such as synthetic rubber, the frictional resistance between the coiled spring body and the elastic body is large when the coiled spring body is elastically deformed.
In addition, since the length of the material of the elastic coil is long and the inside of this coil is also filled with elastic material, the vibrational force from the coiled spring body is distributed extremely well to the surrounding area. Together with the vibration force absorption effect of the elastic body, vibrations can be attenuated even more effectively. Furthermore, this coiled spring body has elasticity in the horizontal direction as well, and exerts a vibration damping effect both in the vertical direction and in the horizontal direction.

Furthermore, in the case of the present invention, the weight of the structure is not only supported by the elastic body such as synthetic rubber, but also by this elastic body and the above-mentioned coiled spring body buried inside, so that the weight of the structure is carried by the elastic body. Less burden,
The durability of the elastic body such as synthetic rubber can be increased, and on the other hand, the elastic body can protect the internal coiled spring body and prevent it from rusting.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the case where the seismic isolation device of the present invention is implemented in a structure, where 1 is a structure installed on the ground, 2 is a foundation of the structure, and 3 is a foundation floor.
One or more elastic supports are provided between the upper fixing plate 5 fixed to the foundation 2 by a coupling device 4 such as a hook bolt, and the lower fixing plate 6 fixed to the foundation floor 3 by a coupling device 7 similar to the above. A body 10 is interposed.

The elastic support body 10 is constructed by laying down one or more coiled spring bodies 12 formed by further spirally winding a long elastic coil 11 made of steel and embedding it inside a synthetic rubber 13 which is an elastic body. It is then molded into one piece. The coiled spring body 12 has reinforcing members 14, 14 extending in a direction parallel to the axis at required locations such as upper and lower portions and/or left and right portions on the outer periphery thereof.
It is desirable to arrange the elastic coil 11 so as to intersect with the elastic coil 11, and to fix each intersection part by welding means to maintain a large elastic strength in the radial direction and improve the shape retention of the spirally wound state. That is, the reinforcement described above can prevent excessive deformation such as displacement in the axial direction of the helical portion due to radial loads. Further, instead of the connecting plate 14, the upper and lower portions of the coiled spring body 12 may be directly fixed to the upper and lower fixing plates 5 and 6 by welding means or the like.

Further, the above-mentioned coiled spring body 10 can be completely embedded inside the synthetic rubber 13, but as shown in the figure, the upper and lower parts of the coiled spring body 12 are connected to the upper and lower fixing plates 5, 6 with or without the connecting plate 14. The outer diameter can be set so that it touches the .

As a seismic isolation device, it is sufficient to support the structure 1 by disposing an appropriate number of the elastic supports 10 between the upper and lower fixing plates 5 and 6, but as shown in the figure, together with the elastic supports 10, A coil spring 15, which is different from the spring body described above, is appropriately arranged between the upper and lower fixing plates 5 and 6 with its axis in the vertical direction.
It is particularly preferable to support the structure by combining the elastic support member 10 and the elastic support member 10 in terms of supporting stability and seismic isolation effect of the structure.

The spiral coiled spring body 12 is designed according to the load of the supporting structure 1, the diameter of the steel material forming the elastic coil 11, and the coil diameter, taking into account the results of seismic isolation tests, the seismic isolation effect, etc. Furthermore, the diameter of the spiral winding circle may be set.

In addition, as a means for embedding the synthetic rubber 13 which is an elastic body, for example, as shown in the figure, the above-mentioned elastic coil 11 is spirally wound around a core body 13' made of synthetic rubber material, and the same synthetic rubber is wrapped around the core body 13'. It is particularly suitable to heat-form the material in a mold in a wrapped state. Furthermore, the invention is not limited to this, and the coiled spring body 12 wound as described above may be set in a mold, and a synthetic rubber material may be wrapped inside and outside the outer diameter circle to heat-form it into a predetermined shape. can.

In any of the above cases, the coil springs 15 disposed in the vertical direction are molded simultaneously with the synthetic rubber 13.
It is also possible to embed it inside.

Further, in the embodiment shown in FIG. 4, an elastic support 10 disposed between the upper and lower fixed plates 5 and 6 has a plurality of wound spring bodies 12, each of which is formed by further spirally winding an elastic coil 11, arranged in parallel at a predetermined interval. The case where this is embedded and molded with synthetic rubber 13 in the same manner as above is shown. In the same manner as in the above embodiment, this elastic support 10 and vertical coil springs 15 are combined and arranged on the upper and lower fixing plates 5 and 6, and installed between the foundation part 2 and the foundation floor part 3. support the structure.

The helical winding direction of the winding spring body 12 may be either left or right, but it is possible to alternately arrange winding spring bodies 12 with different winding directions, or arrange the winding spring bodies 12 in the vertical and horizontal cross directions when viewed from a plane to form the synthetic rubber 13. Alternatively, the elastic support 10 can be placed between the upper and lower fixing plates 5 and 6 so that the internal coiled spring bodies 12 are in the cross directions, depending on the structure and usage. Various decisions can be made.

In the seismic isolation device of the present invention described above, when seismic energy during an earthquake is transmitted to the elastic support 10 between the upper and lower fixed plates 5 and 6 via the foundation floor 3, the seismic isolation device receives the weight of the structure 1. The elastic support 10 deforms due to its elasticity and absorbs the vibration energy. In particular, since the double-coiled spring body 12, which is made by further spirally winding the elastic coil 11, is laid down and buried in the synthetic rubber 13, there is a gap between the elastic coil 11 and the synthetic rubber 13 surrounding it. Since the friction is large and the length of the coil material is large, the vibration force from the coiled spring body 12 is well dispersed, and the vibration force can be further attenuated. Furthermore, the load of the structure 1 is not only supported by the synthetic rubber 13, but also by this synthetic rubber 13.
Since the load can be shared by the coiled spring body 12 buried inside, the load acting on the synthetic rubber is light, the aging and weakening of the synthetic rubber can be prevented, and the durability can be increased.

In any of the above embodiments, as shown in the figure, an elastic support 20 having the same structure as the elastic support 10 described above is interposed between the foundation 2 and the foundation floor 3 on the side of the foundation 2. Therefore, the damping effect against horizontal vibrations can be further enhanced.

〔Effect of the invention〕

As described above, according to the present invention, an extremely excellent vibration absorption and damping effect can be exhibited by the internal coiled spring body that is an elastic support and the elastic body such as synthetic rubber that covers it, and moreover, it is possible to It can stably support loads, improve durability, and exhibit good seismic isolation effects over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing an embodiment of the present invention;
Figure 2 is an enlarged sectional view of a part of the front view, and Figure 3 is the front view.
FIG. 4 is a longitudinal sectional view showing another embodiment. DESCRIPTION OF SYMBOLS 1...Structure, 2...Foundation part, 3...Foundation floor part, 5...Upper fixing plate, 6...Lower fixing plate, 10
...Elastic support, 11...Elastic coil, 12...
Winding spring body, 13...synthetic rubber, 15...vertical coil spring.

Claims (1)

[Claims] 1. A seismic isolation device installed under a structure to support the structure, comprising an appropriate number of elastic supports arranged between an upper fixing plate on the structure side and a lower fixing plate on the ground side, The elastic support is characterized in that one or more wound spring bodies made by further spirally winding a long elastic coil are laid down horizontally and embedded inside an elastic body such as synthetic rubber. Seismic isolation device for structures.