JP2543428B2 - Vibration control device using liquid - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vibration damping device using a liquid, and more particularly to a vibration damping device using a liquid used to suppress vibration of a high-rise building. Is.

[Conventional technology]

2. Description of the Related Art Recently, a high-rise building to be built has a vibration damping device arranged to suppress the vibration of the building due to wind, earthquake, or the like.

As the vibration damping device D, conventionally, as shown in FIG. 4, a liquid 3 such as water is placed in a portion where the amplitude of the high-rise building 1 is the largest, for example, in a container 2 arranged on the rooftop, and a liquid level 3a (free surface)
Are filled so as to form When the high-rise building 1 is shaken by a wind, an earthquake, or the like, the shake is reduced by the pressure generated by the sloshing of the liquid 3.

[Problems to be Solved by the Invention]

However, the vibration damping device D as described above has a problem. That is, in the vibration damping device D, the sloshing frequency fn is Therefore, the sloshing frequency fn is limited by the length L of the container 2 and the height H of the liquid surface 3a.

However, the wind force and seismic force acting on the structure include components in a wide frequency range, and the actual high-rise building has many higher-order modes due to the multi-mass system, resulting in outstanding vibration at multiple frequencies. It will be. Therefore, in order to suppress the vibration having different cycles, it is necessary to provide a plurality of vibration damping devices D having different sloshing frequencies, which not only requires a large installation area but also raises a problem that the construction cost is high.

[Means for solving the problem]

The present invention has been made to solve the above-mentioned conventional problems, in which a liquid is injected into a container so as to form a free surface, and a plurality of superposed liquids are formed below the liquid surface. An intermediate plate made of a plate-shaped porous body and at least one of which is slidable is disposed.

[Work]

As described above, liquid is injected into the container so as to form a free surface, and it is composed of a plurality of plate-shaped porous bodies that are superposed below the liquid surface, and at least one of them is slidable. By arranging the intermediate plate, the vibration above the intermediate plate causes sloshing vibration in the liquid above the intermediate plate to suppress the vibration of the high-rise building and the period is small. When the vibration acts, the liquid below the intermediate plate also acts to suppress the vibration of the high-rise building. On the other hand, the size of sloshing can be adjusted by sliding at least one porous body to change the aperture ratio of the porous body.

〔Example〕

An embodiment of a vibration damping device D using a liquid according to the present invention will be described below with reference to FIGS. 1 to 3.

 FIG. 1 is a perspective view of the vibration damping device D.

In these figures, an intermediate plate 11 made of a porous material is stretched laterally (especially in the horizontal direction) in a box-shaped container 10. A liquid 12 such as water is filled in the container 10 so that the liquid level WL comes to the upper part of the intermediate plate 11.

Specifically, the length L of the container 10 and the depth H ₁ of the liquid 12 from the liquid surface to the intermediate plate 11 are set in advance in the high-rise building 1
The sloshing frequency is set to correspond to the vibration having a large cycle.

The intermediate plate 11 is formed of, for example, a perforated plate in which a large number of holes 13 are opened in a metal plate as shown in FIG. This intermediate plate 11
The distance H ₂ between the bottom plate 15 of the container 10 and the bottom plate 15 of the container 10 is selected so as to cause sloshing vibration corresponding to vibration of a relatively small period in a high-rise building.

Specifically, for long-cycle vibration, sloshing occurs in the fluid at the liquid depth H ₁ formed by the liquid surface and the intermediate plate,
For vibration with a short cycle, sloshing occurs in the fluid having a liquid depth H formed by the liquid surface and the bottom plate.

FIG. 3 shows a case where two intermediate plates 11a having holes 13a and intermediate plates 11b having holes 13b are used in combination, and the positions of the intermediate plates 11a and 11b relative to each other are shown. By adjusting the amount of fluid passing through the intermediate plate 11, it is possible to adjust the attenuation of the fluid (the magnitude of sloshing is adjusted).

As shown in FIG. 3, two intermediate plates 11a and 11b having openings of the same diameter are laminated, one intermediate plate 11b is fixed, and the other intermediate plate 11b is moved by a device (not shown) to form a hole. The aperture ratio of the holes penetrating both 13a and 13b changes.
That is, the attenuation of sloshing can be changed by changing the aperture ratio of the intermediate plate 11 made of a porous body.
Also, since the damping of the fluid changes depending on the magnitude of vibration,
It is important from the standpoint of damping effect to adjust the damping of the fluid according to the magnitude of vibration of the structure.

Therefore, when an external force expected such as a typhoon acts on the high-rise building 1, the aperture ratio of the intermediate plate 11 may be changed in advance according to the magnitude of the expected vibration, and an earthquake or the like. In the case of vibration due to the vibration, the vibration sensor attached to the high-rise building 1 detects the frequency and the amplitude, and automatically moves one intermediate plate of the intermediate plate 11 having a plurality of plate configurations to adjust the attenuation of sloshing. To configure.

The intermediate plate 11 is made of a porous material, and thereby, it is possible to give a flow resistance accompanied by a throttling action when the lower layer moves toward the upper layer among the liquid layers divided into upper and lower layers. is necessary. Therefore, it is best that the intermediate plate 11 is formed of a thin plate material, but it is possible to use a net in some cases.

〔The invention's effect〕

As described above, according to the present invention, a liquid is injected into a container so as to form a free surface, and a plurality of plate-shaped porous bodies are superposed below the liquid surface, and at least one of them is formed. Since a slidable intermediate plate is installed, when a large-cycle vibration is applied to a high-rise building, sloshing vibration occurs in the liquid above the intermediate plate and vibration of the high-rise building can be suppressed. When a vibration with a small cycle acts, the liquid below the intermediate plate also acts and the vibration of the high-rise building can be suppressed. On the other hand, the size of sloshing can be adjusted by sliding at least one porous body to change the aperture ratio of the porous body.

[Brief description of drawings]

1 to 3 show an embodiment of a vibration damping device using a liquid according to the present invention. FIG. 1 is a perspective view, FIG. 2 is a front view of an intermediate plate, and FIG. FIG. 3 is a side sectional view of an intermediate plate having the structure of FIG. And FIG. 4 is a side view of the conventional damping device installed on the high-rise building. 10 ... container, 12 ... liquid, 11, 11a, 11b ... intermediate plate.

Claims (1)

(57) [Claims] 1. A liquid is poured into a container so as to form a free surface, and a plurality of plate-shaped porous bodies are superposed below the liquid surface, and at least one of them is slidable. A vibration damping device using a liquid, characterized in that an intermediate plate is formed.