JPH0410958B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a vibration control device capable of suppressing vibrations of structures caused by wind, earthquakes, etc.

(b) Prior art Recently, in structures such as observation towers, high-rise residential buildings, and high-rise office buildings, where the primary natural vibration period of flexible structures is relatively long, the structure is located near the top of the structure. Attempts are being made to reduce the shaking of structures caused by wind and earthquakes by installing vibration damping devices to absorb vibration energy.

(c) Problems to be solved by the invention Most of these vibration damping devices are composed of large-scale mechanical devices that swing balance weights, and there are problems such as reliability over time and maintenance and inspection of the devices. It has many problems.

Additionally, proposals have been made to absorb vibrations generated in the structure by placing a tank filled with liquid on top of the structure.
No. 38-4536 discloses a damping device in which a liquid tank is provided in the upper part of a structure, a liquid is sealed inside, and a porous filler is filled as a damping member. In this way, when a liquid tank is filled with a filling material as a damping member, the damping ability for the liquid is ensured, but on the other hand, the inside of the liquid tank is occupied by the filling material, making it difficult to ensure a sufficient amount of liquid for vibration damping operation. This has the disadvantage that it is necessary to increase the size of the liquid tank.

In order to eliminate the above-mentioned drawbacks, the present invention aims to provide a vibration damping device that has reliability over time and can be easily maintained and inspected without using complicated mechanical devices. It is something to do.

Another object of the present invention is to provide a vibration damping device that can secure a sufficient amount of liquid for damping operation without increasing the size of the liquid tank, and can effectively exhibit damping performance against the liquid. It has a different purpose.

(d) Means for Solving the Problems That is, the present invention provides a vibration damping device for a structure that is installed on the top of a structure to absorb the vibrations of the structure. A liquid is injected into the liquid tank in such a manner that an open liquid surface is formed inside the liquid tank, and a plate-shaped mesh is installed vertically from the bottom of the liquid tank at least in the center of the liquid tank in the longitudinal direction. One or more meshes are installed so as to reach above the open liquid level, and a plurality of plate-shaped meshes are installed on both sides of the liquid tank in a vertically stacked manner.

Note that the numbers in parentheses are for convenience and indicate corresponding elements in the drawings, and therefore, this description is not limited to the descriptions on the drawings. The same applies to the column "(e). Effect" below.

(e) Effect With the above-described configuration, the present invention acts so that vibrations of the structure due to wind or earthquakes are absorbed by the liquid 5b in the liquid tank 5a oscillating and absorbing the vibration energy.

Further, the present invention operates so that the mesh exerts a damping action on the oscillating liquid.

(f) Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a diagram showing an example of a structure in which an embodiment of the vibration damping device according to the present invention is used, FIG. 2 is a perspective view showing an example of the arrangement of the vibration damping device, and FIG. 3 is a diagram of the vibration damping device. FIG. 4 is a front sectional view of the vibration damping device shown in FIG. 3; FIG. 5 is a perspective view showing another arrangement of the vibration damping device; FIG. 6 is a plan view of the vibration damping device shown in FIG. 5. Figure 7 is a front view showing another example of a structure in which a vibration control device is used.

As shown in FIG. 1, a super high-rise building 1, which is a structure, has a structure 3 erected on the ground 2, and a vibration control device 5 according to the present invention is installed on the top 3a of the structure 3. is set up. As shown in FIG. 2, two vibration damping devices 5 are installed at right angles to each other, and each vibration damping device 5 has a rectangular planar shape as shown in FIGS. 3 and 4. It has a liquid tank 5a. Water or a liquid 5b having a viscosity equal to or greater than water is injected into each liquid tank 5a to form an open liquid level inside, and further on both left and right sides of the liquid tank 5a in the figure. A plate-shaped mesh 5c as a damping member made of stainless steel, vinylon, high-performance fiber, etc. is laminated in two layers, upper and lower in the figure. Further, a mesh 5c formed in a plate shape is vertically provided in the center of the liquid tank 5a so as to protrude from the bottom of the liquid tank 5a onto the open surface of the liquid 5b.

Since the super high-rise building 1 has the above configuration, when the structure 3 shakes due to an earthquake or strong wind,
The damping device 5 installed on the top 3 also shakes. Then, the liquid 5b in the damping device 5 oscillates in synchronization with the vibration of the structure 3, as shown in FIGS. 3 and 4. That is, the oscillation period of the liquid 5b (liquid 5b
As shown in FIGS. 3 and 4, the swing period of b is determined by the length L1 in the long side direction of the liquid tank 5a, the length L2 in the short side direction, and the liquid height L3 in the stationary state of the liquid 5b.
By making the period (determined by
The vibration energy of the skyscraper 1 is absorbed by the waves. When the liquid 5b swings, due to the swing,
The liquid 5b is transferred to the liquid tank 5a as shown by arrow AR.
It flows in the vertical direction on both sides of the wave direction, and in the horizontal direction in the figure, that is, in the swing direction in the center. mesh 5
As already mentioned, a plurality of sheets c are horizontally stacked and provided in parallel in the vertical direction on both sides in the horizontal direction in the figure in the swinging direction of the liquid, which is the longitudinal direction of the liquid tank 5a. Therefore, the mesh 5c is arranged perpendicular to the vertical direction, which is the flow direction of the liquid 5b, and the damping action of the mesh 5c can be effectively exerted on the liquid. Also,
Since the mesh 5c installed in the center of the liquid tank 5a is installed perpendicularly from the bottom of the liquid tank, it is similarly placed at right angles to the liquid flowing in that part. The damping effect of can be effectively exerted on the liquid. As is clear from the figure, the mesh 5c is in the form of a thin plate, so it occupies only a small area of the space in the liquid tank, and the mesh 5c occupies most of the area in the liquid tank when injecting the liquid. It can also be secured as a swinging space.

In this way, when the liquid flows through the mesh in the liquid tank, the viscous resistance that acts between the liquid 5b and the mesh 5c acts in a direction that restricts the movement of the liquid 5b. As a result, liquid 5b
The vibration is attenuated, and the ability to absorb vibration energy is improved.

Note that it goes without saying that one or more meshes may be arranged in the vertical direction in the center of the liquid tank as required.

Furthermore, it goes without saying that the manner in which the vibration damping device 5 is arranged can be appropriately selected depending on the placement location and the required vibration damping performance.
As shown in the figure, in two horizontal directions perpendicular to each other,
Naturally, it is also possible to arrange a plurality of damping devices 5.

Furthermore, as structures to which the vibration control device 5 according to the present invention is applied, flexible structures with relatively long vibration periods are suitable, and in addition to the super high-rise building 1 shown in FIG. Of course, the present invention can also be applied to a tower 6 made of a steel frame or the like as shown in FIG. 7.

Note that the amount of liquid 5b in liquid tank 5a is as follows:
The weight of free water that contributes to rocking is 1 to 1 of the weight of the structure.
3% (the larger the free water weight, the higher the damping effect),
If the damping constant of the damping member is about 2 to 10%, the damping effect can be achieved.

(g) Effects of the Invention As explained above, a vibration damping device for a structure installed on the top of the structure to absorb vibrations of the structure has a liquid tank 5a having a rectangular planar shape. Then, the liquid 5b is injected into the liquid tank so as to form an open liquid surface inside the liquid tank, and a plate-shaped mesh is vertically inserted into the liquid tank from the bottom of the liquid tank at least in the central part in the longitudinal direction of the liquid tank. At least one sheet of mesh is installed so as to reach above the surface of the open liquid, and a plurality of plate-shaped meshes are installed on both sides of the liquid tank in a vertically stacked manner. , it becomes possible to effectively absorb vibrations of structures such as the tower 6 due to wind or earthquakes by swinging the liquid 5b. In addition, since the liquid tank 5a and the liquid 5b have no mechanically movable parts, compared to a mechanical vibration damping mechanism,
It has reliability over time and can be easily maintained and inspected.

In addition, one or more plate-shaped meshes are installed vertically at least in the center of the liquid tank in the longitudinal direction, reaching from the bottom of the liquid tank to above the open liquid surface, and plates are installed on both sides of the liquid tank in the longitudinal direction. Since a plurality of shaped meshes were installed in a stacked manner in the vertical direction, the meshes had a shape perpendicular to the vertical direction, which is the flow direction of the liquid, on both longitudinal sides of the liquid tank in the direction of liquid swing. The damping effect of the mesh can be effectively exerted on the liquid. In addition, since the mesh installed in the center of the liquid tank is installed perpendicularly from the bottom of the liquid tank, it is also placed at right angles to the liquid flowing through that part.
Here too, the damping effect of the mesh can be effectively exerted on the liquid. In addition, Metsuyu is
Because it is plate-shaped, it occupies only a small area of space in the liquid tank, and most of the area in the liquid tank can be secured as a space for injecting and shaking the liquid. without increasing the size of
Sufficient damping capacity for liquid and a sufficient amount of liquid for damping operation can be secured.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a structure in which an embodiment of the vibration damping device according to the present invention is used, FIG. 2 is a perspective view showing an example of the arrangement of the vibration damping device, and FIG. A plan view showing one embodiment, FIG. 4 is a front sectional view of the vibration damping device shown in FIG. 3, FIG. 5 is a perspective view showing an example of the arrangement of the vibration damping device, and FIG. 6 is a plan view of FIG. FIG. 7 is a front view showing another example of a structure in which a vibration control device is used. 1...Structure (high-rise building), 5...Seismic control device,
5a...Liquid tank, 5b...Liquid, 5c...Mesh, 6...Structure (tower).

Claims (1)

[Scope of Claims] 1. A vibration damping device for a structure that is installed on the top of a structure and absorbs vibrations of the structure, comprising a liquid tank having a rectangular planar shape, and a liquid in the liquid tank. is injected into the liquid tank to form an open liquid surface, and a plate-shaped mesh is placed at least in the longitudinal center of the liquid tank in a vertical direction extending from the bottom of the liquid tank to above the open liquid surface. A vibration damping device for a structure comprising: one or more plate-shaped meshes installed on both sides of the liquid tank in the longitudinal direction; and a plurality of plate-shaped meshes stacked vertically on both sides of the liquid tank.