JP3156061B2 - High-rise building damping structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration control structure for a high-rise building which suppresses vibrations generated in the high-rise building due to an earthquake, wind, or the like.

[0002]

2. Description of the Related Art High-rise buildings, especially high-rise buildings, often take a megastructure type. Here, as the megastructure type, for example, there is a type in which a plurality of columns are arranged close to each other to form a group of columns, and the cross-sectional area of the group of columns is relatively large.

Since the wind load is often the dominant factor affecting the megastructure, the design often requires that the deformation of the megastructure be kept within the elastic limit. But like this,
If the design was designed to keep the deformation of the megastructure within the elastic limit, the internal damping of the building would have to be very small, and such megastructure was affected by disturbance vibration such as earthquake or wind. At times, there is a problem that the vibration does not suppress the vibration and gives an excessive response to an earthquake or a wind. Therefore, the response to earthquakes and winds must be kept within an appropriate range, so the degree of freedom in design is reduced, and extra structural members must be added to keep the response within the appropriate range. There is a problem that the cost is increased.

By the way, in order to suppress vibrations generated in buildings due to earthquakes and winds, there has been proposed a system in which a vibration damping device (damper) utilizing interlayer deformation of buildings is added. The deformation is dominated by bending deformation caused by the expansion and contraction of the columns in the axial direction, and there is not so much interlayer deformation. Therefore, even if a vibration damping device using interlayer deformation is added, the vibration generated in the building is effective. There is a disadvantage that it cannot be suppressed.

In order to solve this drawback, there has been proposed a vibration damping structure in which a floor or a beam constituting a substructure is suspended from a megastructure, and a damper is interposed between the floor or a beam and the megastructure. See JP-A-1-247667 and JP-A-2-194279).

[0006]

However, the conventional vibration damping structure in which the substructure is suspended from the megastructure and a damper is interposed between the substructure and the megastructure has the following problems to be solved. is there.

That is, in this conventional vibration damping structure, since the substructure is suspended from the megastructure, the natural frequency of the substructure is determined only by the suspension length, and a plurality of vibrations such as an earthquake are caused. It is difficult to tune with the frequency of the mode,
In addition, high-order vibration modes are not so excited.

In the conventional vibration damping structure, since a damper is interposed between the megastructure and the substructure, an out-of-plane load may act on the megastructure. The megastructure may buckle and deform due to the load.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and can be tuned to a frequency comprising a plurality of vibration modes, and furthermore, generation of an out-of-plane load is suppressed to prevent buckling. It is an object of the present invention to provide a vibration control structure of a high-rise building which can be used.

[0010]

According to the present invention, there is provided a vibration control structure for a high-rise building, which comprises a mega frame provided over the entire height of the high-rise building.
In addition, a plurality of sub-frames having different vibration characteristics from the mega frame
Provided to support and absorb vibration energy into the subframe
A high-rise building provided with a damper,
Mega frames have vibration characteristics in which bending deformation is more pronounced than shear deformation
In addition to having the property, the sub-frame
Each of the sub-frames is fixed to the mega frame
Shear deformation is caused so that each layer of the frame causes interlayer deformation.
It has better vibration characteristics than deformation,
Caused by bending deformation of a mega frame under shearing of a sub-frame
The vibration caused by deformation is transferred to
Damper acts as a vibration damper against the deformation of each layer of the sub-frame
It is characterized by having been arrange | positioned so that it may have.

[0011]

According to the damping of high-rise buildings the present invention, when an external force such as earthquake or wind acts on the high-rise building, firstly it mega Frames vibrates, from the vibration of the mega Frames shear deformation
The bending deformation is also excellent. Sub frame for mega frame
The structure is supported and fixed so that it can relatively vibrate
In, most of the vibrational energy of the mega-Frames can be transferred to the sub-Frames, but sub-Frames to vibration, the vibration of the sub-Frames
The shear deformation is superior to the bending deformation. So
Then, due to the vibration caused by the shear deformation of the subframe, the floors or beams of the multiple layers constituting the subframe are interlaminarly deformed, and this interlaminar deformation is suppressed by the damper, and finally the vibration of the high-rise building is effectively damped. Is done.

In this manner, the kinetic energy of the megaframe of a high-rise building vibrating in a bending type can be efficiently transferred to the subframe vibrating in a shearing type. In addition, the multi-layer floors and the like of the sub-frame constitute an inertial mass body, the structure between the multi-layer floors and the like is formed as a spring, and a damper is interposed between the layers. When vibrations composed of a plurality of vibration modes are excited in a building by an external force such as an earthquake or wind, it can be set to have a natural frequency corresponding to the plurality of natural frequencies of the high-rise building (Japanese Patent Application (See Hei 2-102252). Therefore, if the primary natural frequency of the sub-frame is tuned to the lowest frequency of the target frequency in the natural frequency band of the entire high-rise building, the sub-frame has a plurality of vibration modes. Vibration components above the frequency are very easily transferred to the subframe. As described above, the vibration energy input to the sub-frame vibrating in the shearing type causes interlayer deformation of a plurality of floors and the like of the sub-frame, and is absorbed by the damper effective for interlayer deformation.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration damping structure for a high-rise building according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a vibration damping structure 1 of a high-rise building according to this embodiment.
As shown in FIG. 1, a mega frame 10 arranged along the height direction of a high-rise building, a sub-frame 20 having a plurality of floors 21 and beams 22 and housed in the mega frame 10, and a sub-frame 20 And a damper (30) for damping the vibration transferred to (20).

The mega frame 10 has a plurality of pillars 11 arranged in a vertical direction, a beam 12 connecting the upper portions of the plurality of pillars 11, and a predetermined length along the height of the pillars 11. (For a plurality of floors). The column portion 11 has a plurality of columns, for example, four columns arranged at four corners of a rectangle, and has a large total sectional area.

The sub-frame 20 includes a plurality of pillars 23 integrally fixed to the beam portions 12 and 13 of the megaframe 10, and a plurality of floors 21 disposed between the pillars 23 corresponding to each floor.
And a beam 22 disposed below the floor 21. The connection structure between the column 23 and the beam portions 12 and 13 is as follows.
The reinforcing bar in the column 23 is fixed between the reinforcing bars in the beams 12, 13 and concrete is cast. Here, the tuning frequency can be made variable by adjusting the strength of the column 23. Further, by adjusting the rigidity distribution of the column 23, it is possible to excite higher-order modes of vibration in the sub-frame 20.

The beams 22 and the columns 23 forming the sub-frame 20 are the same as the columns 11 and the beams 1 forming the mega-frame 10.
The frame has a small cross-sectional area of 2 and 13 and has a wall (not shown) in addition to the column 23 and the beam 22. In addition, as a structure which comprises the subframe 20, RC structure, S structure,
An appropriate structure such as an SRC structure can be adopted.

The damper 30 is disposed between a plurality of floors 21 or beams 22 so as to have a vibration damping action against these interlayer deformations.
And a damper body 32 arranged between the beam 22 and
A brace 31 is provided for connecting the damper body 32 to the adjacent floor 21 or beam 22. The amount of suppression of interlayer deformation by the damper 30 is determined based on the overall efficiency and safety of the vibration damping structure system of the present embodiment. Needless to say, the damper 30 can employ various damping mechanisms capable of suppressing the deformation between layers.

Further, as the damper 30, a mega frame 1
From the viewpoint of the relative deformation between the zero and the sub-frame 20 and the required vibration damping performance, it is preferable to have a characteristic that operates only on a higher-order component than the target vibration period. By having such characteristics, the load on the damper 30 can be reduced, and the clearance formed in the damper body 32 can be reduced, which is extremely advantageous.

Numerals 33 and 34 in the drawing denote dampers having the same structure as the damper 30.
Are arranged between the floor 21 or the beam 22 constituting the sub-frame 20 and the sub-frame 20 and the mega frame 10. Such dampers 33 and 34 should be avoided as much as possible. That is,
It is preferable that the damper is disposed basically within the sub-frame 20, and that only a portion where a reaction force can be expected be provided between the mega frame 10 and the sub-frame 20 with a restriction.

Next, the operation and effect of the embodiment of the present invention will be described based on a specific model. In order to show the effect of the present invention, an analysis model as shown in FIG. 2 was set. (A) in the figure is a model in which a sub-frame is fixed in series to a mega-frame, and shows a conventional structure type. (B) in the figure shows the structural form of the present invention in a model in which the sub-frames are divided into a plurality of parts and the upper and lower columns 23 of the respective sub-frames 20 are fixed to the mega frame 10. In the figure, (b-
1) shows a case where the primary natural frequency of the sub-frame 20 is tuned to the primary natural frequency of the model (a), and (b−
2) shows a case where the primary natural frequency of the sub-frame 20 is tuned to the third natural frequency of the model (a). In addition,
In order to simulate the behavior of a high-rise building, it was assumed that all deformations of the megaframe were bending deformations due to the axial expansion and contraction of the columns. In (b), it is assumed that the sub-frame is only subjected to shear deformation. M1 to m4, K1 to K4, k in each model
Table 1 shows specific numerical values of 1 to k4.

[0022]

[Table 1]

FIGS. 3 and 4 show the EI Centro 1940 NS waveform assumed as the input earthquake motion and the response results in the models (a), (b-1) and (b-2). Here, in each model, a time history waveform of the base shear and the overturning moment at the base of the building, which is a design problem, is shown. Table 2 shows the maximum response values of the base shear and the falling moment in each model.

[0024]

[Table 2]

As is clear from FIGS. 3 and 4 and Table 2,
Model (b) tuned to the primary natural frequency of model (a)
In -1), it can be seen that both the base shear and the overturning moment can be significantly reduced. The model (a)
In the model (b-2) tuned to the third natural frequency of
Although it is not so effective in reducing the overturning moment,
It can be seen that the effect of reducing the base shear is as effective as the model (b-1). In addition, if the tuning frequency is increased, the clearance required between the mega frame and the sub-frame is reduced, so that the designer is given a degree of freedom to select the tuning frequency depending on the case.

[0026]

As described above, according to the vibration damping structure for a high-rise building of the present invention, bending deformation is more predominant than shear deformation.
Shear deformation is more pronounced than bending deformation
The sub-frame is supported and provided, and the sub-frame is deformed between layers.
Since the damper is arranged so as to have a vibration damping effect on
When an external force such as an earthquake or wind acts on a high-rise building, first the mega-frame vibrates so as to bend and deform , and most of the vibration energy of the mega-frame is transferred to the sub-frame so that the sub-frame undergoes shear deformation. Vibration causes the floors or beams of a plurality of layers constituting the subframe to undergo interlayer deformation, and this interlayer deformation is suppressed by the damper, and finally the vibration of the high-rise building is effectively damped.

As described above, the kinetic energy of the mega frame of the high-rise building vibrating in the bending type can be efficiently transferred to the sub-frame vibrating in the shear type. In addition, the multi-layer floors and the like of the sub-frame constitute an inertial mass body, the structure between the multi-layer floors and the like is formed as a spring, and a damper is interposed between the layers. When vibrations composed of a plurality of vibration modes are excited by an external force such as an earthquake or wind in a building, it can be set to have a natural frequency corresponding to a plurality of natural frequencies of the high-rise building. If the primary natural frequency of the sub-frame is tuned to the lowest frequency of the target frequency in the natural frequency band of the entire high-rise building, the sub-frame has a plurality of vibration modes. These vibration components are very easily transferred to the subframe. As described above, the vibration energy input to the sub-frame vibrating in the shearing type causes interlayer deformation of a plurality of floors and the like of the sub-frame, and is absorbed by the damper effective for interlayer deformation.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a vibration damping structure of a high-rise building according to an embodiment of the present invention.

FIG. 2 is a diagram showing an analysis model obtained by modeling the structure of a conventional high-rise building and the structure of a high-rise building according to one embodiment of the present invention.

[Figure 3] EI Centro 1940N assumed as input earthquake motion
FIG. 3 is a diagram illustrating an S waveform and a response result in the model (a) of FIG. 2.

Fig. 4 EI Centro 1940N assumed as input earthquake motion
The model (b-1) and the model (b) of FIG.
It is a figure which shows the response result in -2).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration control structure of high-rise building 10 Mega frame 11 Column part 12 and 13 Beam part 20 Subframe 21 Floor 22 Beam 23 Column 30 Damper 31 Brace 32 Damper body

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mamoru Yoshida 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Kazuhiko Isoda 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu (56) References JP-A-64-48978 (JP, A) JP-A-4-312684 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E04H 9 / 02

Claims (1)

(57) [Claims] (1) A mechanism provided over the entire height of a high-rise building.
A plurality of substructures having different vibration characteristics from the megaframe
The sub-frame is supported and provided with vibration energy.
The damping structure of a high-rise building equipped with a damper to absorb
Therefore , the mega frame has a vibration in which bending deformation is more predominant than shear deformation.
With sub-frames on each of its columns
The lower part is fixed to the mega frame,
Shear deformation that causes each layer of the subframe to cause interlayer deformation
Has superior vibration characteristics than bending deformation, and
Vibration caused by bending deformation of mega frame in sub-frame
The vibration is transferred to the shear deformation, and the damper controls the interlayer deformation of each layer of the sub-frame.
A vibration control structure for a high-rise building, which is arranged to have a vibration action .