JPH086488B2 - Torsional vibration suppressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a torsional rocking suppression device which is installed in an upper layer of a building or the like, and which reduces torsional vibration caused in the building by an earthquake or the like. Regarding

<< Conventional Technology >> Various types of rocking suppression devices have been proposed in the past for restricting the shaking of buildings against earthquake motions. For example, a summary of academic lectures at the Architectural Institute of Japan (Kinki)
(October 1987) There was something like that described on pages 905-906. That is, an actuator or the like that is expanded and contracted in the direction of ground motion between a building supported on the ground through a lengthening means such as a sliding support member composed of an isolator or rollers made of laminated rubber or the like, and the ground. It is considered to insulate the building from the moving ground and to maintain the building in a constant position as much as possible by providing the power means for A known damping mechanism is known.

<Problems to be solved by the invention> However, in a building, for example, the north side may be set back, and when the building is viewed two-dimensionally, the building may be designed or the site conditions may not be satisfied. In many cases, the rigidity and the center of gravity of the building itself become unbalanced, which causes torsional vibration during an earthquake such as when a vibration force acts on a building. There is a problem that the torsional vibration cannot be suppressed.

In addition, the upper moment of the building has a larger moment of inertia, so the effect of twisting is greater.Therefore, the higher the building, the more it is necessary to prevent uneven rigidity and uneven center of gravity. Regulations, that is, design restrictions, were becoming stricter.

The present invention has been made in view of the above background, and an object thereof is to provide a torsional vibration suppressing device capable of suppressing torsional vibration caused in a building.

<< Means for Solving the Problem >> A first invention is a structure in which a cantilever-like base is provided in a building so as to be swingable in the direction of torsional vibration, and a free swing end and a fixed end of the base. It is characterized by comprising a mass body movably provided so that its installation position can be changed between them, and a damper provided on the oscillating free end side of the pedestal part for damping the oscillating movement.

According to a second aspect of the present invention, elastic support columns having different torsional rigidity are arranged side by side in a building, and these elastic support columns are supported like cantilevers, and a platform is provided so as to be swingable in the torsional vibration direction of the building. Further, a mass body is fixedly provided on the swing free end side of the base portion, and a damper for damping the swing is provided on the swing free end side of the base portion.

<< Operation >> According to the first aspect of the invention, when the cantilever-like pedestal-like free swinging end of the cantilever-like body is largely shaken and twisted due to the torsional vibration of the building, the mass body and the damper of the pedestal are torsionally oscillated. Function as a damper system for. Therefore, the vibration energy of the torsional vibration induced in the building is absorbed by this damper system, and the torsional vibration is suppressed.

In addition, since the mass body is movable so that its installation position can be changed with respect to the platform, the damper system, that is, the natural period of the platform including the mass can be changed and adjusted, and torsional vibration of a wide range of cycles can be achieved. Can be adapted to.

According to the second invention, while exhibiting the same damper function as the first invention, elastic support columns having different torsional rigidity arranged in parallel in a building are supported like a cantilever so that the platform can swing freely. By providing the elastic support columns, by appropriately setting the torsional rigidity, the natural period of the damper system is adjusted, and the torsional vibration is suppressed.

<< Examples >> Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a preferred embodiment of a torsional vibration suppressing device according to the present invention. Further, FIG. 2 is a schematic perspective view of a building for explaining the application of the torsional vibration suppressing device shown in FIG.

The first invention is basically a cantilever-like pedestal 2 provided on a building 10 so as to be swingable in the torsional vibration direction,
A mass body 3 movably provided between the free swing end 2a and the fixed end 2b of the base 2 so that its installation position can be changed;
And a damper 4 provided on the side of the free swing end 2a for damping the swing.

This torsional vibration suppressing device 1 is a cantilever type base 2
A mass body 3 movably mounted on the base 2 so that its installation position can be changed, and a damper 4 for damping the vibration of the base 2 to prevent torsional vibration of the building 10. It is a damper system.

The base 2 is made of a substantially rectangular substrate, and a plurality of support columns 21 are fixedly erected on the lower surface side of the base 2.
It is a so-called cantilever method by placing it close to one end side. In addition, the support columns 21 are, for example, the upper layers of the building 10,
It is fixed to the floor surface of a given floor, so that the base 2 is
It is fixed to.

The mass body 3 is guided by guide means such as a rail (not shown) on the base 2, and its swing free end 2a side and fixed end.
It is configured such that the installation position can be changed between the support pillar 21 side which is the 2b side.

That is, the mass body 3 is placed on the base portion 2 such that the installation position of the mass body 3 can be changed by the distance l to the point P on the base portion 2 which is the center of gravity due to the support of the plurality of support columns 21. The natural period of the base 2 with respect to the torsional vibration is arbitrarily changed by the movement of the position, and the change and adjustment can be automatically controlled according to the vibration period of the torsional vibration of the building 10.

The damper 4 is a viscous damper that is damped by the viscous material 40, and is arranged on the swing free end 2a side of the base 2.

That is, according to such a configuration, the pedestal portion 2 is largely shaken and twisted on the side of the swing free end 2a accompanying the torsional vibration of the building 10 to which the supporting column 21 is fixed. It becomes a damper system that resonates with. Therefore, the vibration energy of the torsional vibration induced in the building 10 is absorbed by this damper system, and the torsional vibration can be suppressed.
Further, since the natural period of the base portion 2 with respect to the torsional vibration can be arbitrarily changed by moving the installation position of the mass body 3, it is possible to deal with the torsional vibration with a wide range of periods.

The torsional vibration suppressing device 1 is installed additionally to the building 10 and does not limit the position of the center of gravity or the like of the building 10. Therefore, the shape design of the building 10, etc. Can be freely performed, and the degree of freedom in design can be improved. In other words, according to the present invention, even for a building whose center of gravity is biased due to various design conditions such as a set pack, torsion vibration can be isolated without changing the various design conditions.

On the other hand, since the torsional vibration can be suppressed, it is not necessary to reinforce the building 10 against the torsional vibration, and the cost of the skeleton can be reduced.

In the second invention, basically, elastic supporting columns 21a and 21b having different torsional rigidity are arranged in parallel in the building 10, and these elastic supporting columns 21a and 21b are supported like a cantilever, so that the building 10
The base portion 2 is provided so as to be swingable in the torsional vibration direction, and the mass body 3 is provided by being fixed to the swing free end 2a side of the base portion 2, and the swing is provided on the swing free end 2a side of the base portion 2. A damper 4 for damping motion is provided. That is, in the above-described embodiment, the inertial moment of the damper system is changed and adjusted by moving the installation position of the mass body 3, but in this embodiment, the spring characteristics of the support columns 21a and 21b are changed and set. .

Specifically, as shown in the illustrated example, four vertical and horizontal elastic support columns 21 are provided.
When supporting the base 2 with a and 21b, the fixed end 2b of the base 2
Two support columns 21a and 21b on each of the side and the central side are configured by combining columns having different torsional rigidity, such as solid columns or hollow columns or columns having a channel-shaped cross section, to support the base portion 2 By appropriately changing and setting the elastic spring characteristic in this case, the swinging characteristic of the base portion 2 can be changed to arbitrarily set the natural period of the base portion 2 with respect to torsional vibration.
Even with this structure, torsional vibration of the building 10 can be suppressed as in the case of the above-described embodiment.

<< Effects of the Invention >> As described in detail in the above, according to the torsional vibration suppressing device of the present invention, the following excellent effects are achieved.

(1) Since the pedestal part accompanying the torsional vibration of the building becomes a damper system in which its swing free end side is largely shaken and resonates, the vibration energy of the torsional vibration is absorbed by the damper system, and the torsional vibration is generated. Can be suppressed.

(2) Because it is installed in addition to the building and does not limit the position of the center of gravity of the building, it does not hinder the freedom of architectural design, but it is designed freely. The seismic isolation of the completed building can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the first invention, FIG. 2 is a schematic perspective view of a building explaining its application, and FIG. 3 is a perspective view showing an embodiment of the second invention. It is a figure. 1 ... Torsional vibration suppressor, 2 ... Base 2a ... Free swing end of base, 2b ... Fixed end of base 3 ... Mass, 4 ... Damper 10 ... Building, 21 ... … Supporting columns 21a, 21b …… Elastic supporting columns

Claims (2)

[Claims] Claims: 1. A cantilever-like base provided on a building so as to be swingable in the direction of its torsional vibration, and its installation position is movable between a free swing end and a fixed end of the base. A torsional vibration suppressing device comprising: a freely provided mass body; and a damper, which is provided on the swing free end side of the base portion and which damps the swing thereof. 2. An elastic support column having different torsional rigidity is provided side by side in a building, and a support is provided so as to be supported by these elastic support columns like a cantilever so as to be swingable in the torsional swing direction of the building. And a mass body fixed to the swing free end side of the base portion, and a damper for damping the swing motion provided on the swing free end side of the base portion. apparatus.