JPH1068247A - Base isolation structure for building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict the swinging or the falling down of a building for preventing pulling force from working to isolators and effectively restrict the vibration of the top side of the building by appropriately arranging the isolators. SOLUTION: One set of three isolators 10a, 10b and 10c are arranged along the virtual circular arc 16 around the curvature center O set to the center of the top section of a multistoried building 12 in equally spaced relation, and the isolators 10a and 10c, which are arranged on both sides of the isolators 10b0, are made inclined facing the multistoried building. The reaction component force f2 toward the center O is generated in the inclined isolators 10a and 10c to a horizontal vibration force F as the component force of reaction force f1 to restrict the multistoried building 12 from swinging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an isolator installed on a foundation of a building to prolong the natural period of the entire building, thereby preventing the resonance of the building at the time of vibration input by an earthquake. The present invention relates to a seismic isolation structure for a building that suppresses the swing of an object.

[0002]

2. Description of the Related Art In recent years, various devices have been proposed for damping buildings such as high-rise buildings. Among them, as shown in FIG.
Is installed on the foundation 3 of the building 2. In this seismic isolation structure, the isolator 1 is installed on the foundation 3 to increase the natural period of the entire building 2 to prevent the building 2 from resonating even when an earthquake is input. Thus, the shaking of the building 2 can be suppressed.

[0003]

However, in such a conventional seismic isolation structure, the laminated rubber used as the isolator 1 is basically formed by alternately laminating and bonding rubber plates and steel plates. It is used with its lamination direction arranged vertically. Therefore, isolator 1
Has sufficient strength against compressive load,
The resistance to a tensile load acting in the drawing direction is extremely small.

Accordingly, when the building 2 swings greatly as shown in FIG. 6, a remarkably large tensile load acts on the isolator 1 located on the outer side of the building 2 in the falling direction (left side in the figure). The isolator 1 may be destroyed. In particular, there is a problem that as the building 2 is made higher, it is difficult to handle the pulling force due to the overturning moment acting on the isolator 1.

In view of the above-mentioned problems, the present invention devises the arrangement of the isolator, thereby suppressing the swinging of the building, that is, the tendency of the building to fall, thereby preventing the pull-out force from acting on the isolator. It is another object of the present invention to provide a seismic isolation structure for a building that can effectively suppress vibration on the top side of the building.

[0006]

According to the present invention, there is provided a seismic isolation structure for a building in which an isolator is installed in a seismic isolation space formed between the building and a foundation thereof. In the above, the seismic isolation space is formed into a downwardly convex arc-shaped section, and an isolator is disposed in the arc-shaped seismic isolation space.

In the seismic isolation structure of a building according to the present invention, the seismic isolation space between the building and its base is formed into a downwardly projecting arc shape, and the arc-shaped seismic isolation structure is formed. Since the isolator is arranged in the space, the isolator is arranged with an inward inclination toward the building from directly below the center of the building toward the outside of the building. Therefore, in response to a horizontal vibration input, a drag component toward the inside of the building is generated in the inclined isolator as a component force of the reaction force, and the drag component toward the inside of the building is generated by the component of the building. As a force component for suppressing the swing, the tendency of the building to fall can be suppressed.

[0008] Further, the drag component is directed inward toward the building,
More specifically, the building tends to swing around the center of curvature of the circular arc, which is taken inside the building in order to establish a downwardly convex arc-shaped seismic isolation space. Therefore, the building swings around the height centered on the center of curvature, and compared to the conventional seismic isolation structure where the isolator is simply arranged vertically, the amount of vibration displacement and vibration on the top side of the building The swing can be suppressed by reducing the acceleration.

Further, since the isolator is disposed in the downwardly convex arc-shaped seismic isolation space as described above, the structure is provided by the isolator which is disposed inwardly inward along the seismic isolation space. Can be stably supported in the long term, and the residual strain after the seismic force acts can be quickly eliminated.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 3 show an embodiment of a seismic isolation structure for a building according to the present invention. FIG. 1 is an enlarged view of a main part of a seismic isolation space, and FIG. FIG. 3 is an explanatory diagram showing a behavior of a building at the time of vibration input.

This embodiment is basically a building in which isolators 10a, 10b and 10c are installed in a base-isolated space 14 formed between a high-rise building 12 as a building and a base portion 20 thereof. In the seismic isolation structure of the above, the seismic isolation space 14 is sectioned in a downwardly convex arc shape, and the isolator 10a, 10b, 10
c.

That is, in the seismic isolation structure of the present embodiment, as shown in FIG. 1, the isolators 10a, 10b, and 10c are connected to a seismic isolation space 14 of a high-rise building 12 as a building shown in FIG.
It is installed and configured. The isolator 10a,
10b and 10c are each configured as a laminated rubber,
They are juxtaposed in the width direction of the high-rise building 12 (left-right direction along the paper).

The isolators 10a, 10b, 10
3 are arranged at equal intervals along an imaginary arc 16 having a center of curvature O set at the center of the top 12a of the high-rise building 12 as shown in FIG. Therefore, the isolator 1
The isolator 10b disposed at the center among the 0a, 10b, and 10c is disposed vertically, and the isolators 10a and 10c disposed on both sides are inclined inward toward the inside of the high-rise building 12, respectively.

With the above structure, in the seismic isolation structure of the present embodiment, the natural period of the high-rise building 12 is extended by the three isolators 10a, 10b and 10c installed in the seismic isolation space 14, and the high-rise building 12 prevents them from resonating with the seismic input. At this time, the three isolators 10a, 10b, and 10c are connected to the top 12a of the high-rise building 12.
A virtual arc 16 centered on the center of curvature O set at the center
2, the isolator 1c is inclined with respect to a horizontal vibration input F as shown in FIG.
At 0c, a drag component f2 toward the center of curvature O is generated as a component of the reaction force f1, and the drag component f2 in the direction of the center of curvature O is a force component for suppressing the swing of the high-rise building 12,
The tendency of the tall building 12 to overturn can be suppressed.
A similar function is exerted even in the left isolator 10a.

Therefore, the high-rise building 12 is supported from both sides by the drag component f2.
Of the isolator 10a,
By preventing a tensile force from acting on 10b, 10c, it is possible to prevent the isolators 10a, 10b, 10c from being damaged.

Since the drag component f2 is directed toward the center of curvature O as described above, the high-rise building 12 tends to swing around the center of curvature O set at the center of the top 12a. For this reason, the high-rise building 12 swings in a direction opposite to the movement of the building in the conventional seismic isolation structure in which the isolator is simply arranged vertically, while reducing the amount of vibration displacement and vibration acceleration of the top 12a. Movement can be effectively suppressed.

Further, in the present embodiment, as described above, the isolators 10a, 10b, and 10c are connected to the center of curvature O.
, The high-rise building 12 can be stably supported for a long period of time by the curvature of the seismic isolation space 14 at this time, and the residual strain after the seismic force acts is also promptly increased. Can be eliminated.

In the above embodiment, the center of curvature O is set to the high-rise building 1
2 is set at the center of the top 12a, and it is most desirable to provide it at the top 12a as described above. However, the present invention is not limited to this. The swinging of the high-rise building 12 can also be effectively suppressed by setting the space between the high-rise buildings. In this embodiment, three isolators 1 are used.
0a, 10b, and 10c have been disclosed as one set,
It is sufficient to provide two or more isolators without being limited to this, and in this case, it is desirable to arrange them symmetrically. Further, the building is not limited to the high-rise building 12, and can be applied to other structures, for example, a building such as a tower.

In the above embodiment, the isolator 1 is provided in the downwardly convex arc-shaped base isolation space 14 drawn with a single radius of curvature.
Although 0a to 10c are arranged, as shown in FIG. 4, concentric seismic isolation spaces drawn with different curvature radii R1 and R2 with respect to the same center of curvature O are set, and the isolators 10a to 10c are respectively provided for these. 10c may be arranged. In this case, although the amount of distortion or the like is slightly different between the isolators 10a to 10c arranged in the respective seismic isolation spaces, this can be dealt with by adjusting the height of the isolator.

[0020]

As described above, in the seismic isolation structure for a building according to the present invention, the seismic isolation space between the building and its foundation is formed into a downwardly convex arc-shaped section. Since the isolators are arranged in the seismic isolation space of, each isolator is arranged with an inward inclination toward the building from directly below the center of the building toward the outside. Therefore, the inclined isolator can generate a drag component directed toward the inside of the building in response to the vibration input in the horizontal direction. The tendency of the object to fall can be suppressed.

Further, since the drag component is directed toward the center of curvature of an arc to be taken inward of the building in order to establish a downwardly convex arc-shaped seismic isolation space, the building is positioned at the height position having the center of curvature. And the amount of vibration displacement and vibration acceleration on the top side of the building can be reduced to suppress the vibration.

Further, since the isolator is disposed in the downwardly convex arc-shaped seismic isolation space, the structure is stably provided for a long period of time by the isolator arranged inwardly inward along the seismic isolation space. This provides various excellent effects that the residual strain after the seismic force acts can be quickly eliminated.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a main part of a base isolation space showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a component force generated in an isolator used in one embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a behavior of a building at the time of vibration input in one embodiment of the present invention.

FIG. 4 is an enlarged view of a main part of a base-isolated space showing another embodiment of the present invention.

FIG. 5 is a schematic configuration diagram showing a conventional seismic isolation structure.

FIG. 6 is a schematic configuration diagram showing an operation state of a conventional seismic isolation structure.

[Explanation of symbols]

 10a, 10b, 10c Isolator 12 High-rise building 12a Top 14 Seismic isolation space 16 Virtual arc 20 Base O curvature center

Claims (1)

[Claims] 1. A seismic isolation structure for a building in which an isolator is installed in a seismic isolation space formed between a building and a foundation thereof, wherein the seismic isolation space is sectioned in a downwardly convex arc shape. Then, an isolator is installed in this arc-shaped base-isolated space.