JPH0842186A - Vibration control structure for multistoried building - Google Patents

Abstract

PURPOSE:To realize an optimum damper constant according to a purpose in a vibration control structure for multistoried building provide a damping effect to vertical direction, and improve habitability performance and safety performance. CONSTITUTION:A mega frame 10 is arranged along the vertical direction of a multistoried building, a plurality of layers of sub-frames 20 having floors 21 are provided within the mega frame 10. The floors 21 and column parts 11 constituting the mega frame 10 are connected to each other through dampers 30 capable of mainly damping a horizontal vibration, and controlling the damping force.

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 or wind.

[0002]

2. Description of the Related Art High-rise buildings, especially super high-rise buildings, often take the form of mega frames. Here, as the mega frame format,
For example, a plurality of columns are arranged close to each other, and a cross-sectional area of a group of columns is relatively large.

Of the several disturbance factors that act on the mega frame, the wind load often dominates, so it is often unavoidable to design the deformation of the mega frame within the elastic limit. However, if the design is designed so that the deformation of the mega frame is almost within the elastic limit, the internal damping of the building will be very small, and such a mega frame will be resistant to earthquakes and winds. However, there is a problem in that it gives an excessive response. Therefore, the response to earthquakes and winds must be kept within an appropriate range, which reduces design flexibility and requires additional structural members to keep the response within the appropriate range. There is a problem that this leads to an increase in

By the way, in order to suppress the vibration generated in a building due to an earthquake or wind, a vibration damping device (damper) utilizing the interlayer deformation of the building has been devised, but in a high-rise building, especially in a super high-rise building. The deformation is dominated by the bending deformation caused by the expansion and contraction of the column in the axial direction, and the interlayer deformation does not occur much. Therefore, the vibration generated in the building is effective even if the damping device using the interlayer deformation is added. There is a drawback that it cannot be suppressed to

In order to solve this drawback, a frame structure having a plurality of layers of floors and beams and damping in synchronization with the cycle of a sub frame housed in a mega frame is disclosed in Japanese Unexamined Patent Publication No. 1-247667.
It is proposed in JP-A-2-194279 and Japanese Patent Application No. 2-307362.

[0006]

However, the optimum damping force of the damper differs depending on the response value to be minimized. For example, the damper amount and the response of the sub-frame for minimizing the interlayer displacement. The damping force to minimize the acceleration is different. Enhancing habitability is required for strong winds or earthquake motions that a building is likely to experience a few times a year, and ensuring structural safety against winds or earthquakes that are assumed in earthquake-resistant or wind-resistant designs. Must be the highest priority. In addition to this, the above structure is effective only for horizontal response reduction,
It has no effect on vertical movement. In the case of middle and high-rise buildings, the vertical natural frequency is higher than in the horizontal direction, so it is less problematic, but in the case of ultra-high-rise buildings, the vertical natural frequency is the strongest vertical motion of seismic motion. Since it enters the area, it may not be negligible in terms of design.

The present invention has been made in view of the above circumstances. By making the damper variable, an optimum damper constant is realized according to the purpose, and a damping effect in the vertical direction is also provided, so that the living performance is improved. The purpose is to provide a vibration control structure for high-rise buildings that improves safety performance.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and the first aspect of the present invention is to provide a mega frame arranged along the height direction of a high-rise building, In a vibration control structure for a high-rise building, which comprises a sub-frame composed of beams or the like and housed in the mega frame, and a damper for damping vibration transferred to the sub-frame, the damper is vertically and horizontally arranged. It is characterized in that it is provided between the mega frame and the sub frame or in the sub frame so as to suppress vibration in at least one of the directions.

A second aspect of the present invention is characterized in that the damping force of the damper is variable, and a third aspect is that the natural frequency of the sub-frame is tuned according to the natural frequency of the mega-frame.

[0010]

According to the present invention, the damper is provided between the mega frame and the sub frame or in the sub frame so as to suppress vibration in at least one of the vertical direction and the horizontal direction. As a result, it is possible to obtain a vibration damping structure that is effective for both horizontal response reduction and vertical response reduction.

Further, by making the damping force of the damper variable, an optimum damper constant can be set according to the purpose, and for example, the living performance can be maximized and the safety performance can be maximized. Further, by tuning the natural frequency of the sub frame according to the natural frequency of the mega frame, the vibration energy from the mega frame to the sub frame is easily transferred, and the damping effect is enhanced.

[0012]

1 and 2 show the outline of a high-rise building to which the vibration damping structures 1 and 2 according to claims 1 and 2 of the present invention are applied, respectively. Each damping structure 1, 2 has a mega frame 10 arranged along the height direction of a high-rise building, and a mega frame 10
A plurality of sub-frames 20 housed inside and a sub-frame 20
And a damper 30 for damping the vibration transferred to the.

The mega frame 10 has a plurality of vertically arranged pillars 11, an uppermost beam portion 12 connecting the upper ends of the pillars 11, and at least one intermediate beam portion extending between the pillars 11. 13 and 13. The pillar portion 11 has a plurality of (for example, four) pillars (not shown) arranged at four corners of a rectangle to set a large cross-sectional area. Sub frame 20
Is fixed to the floor 21 and the beam portions 12 and 13 fixed through the floor 21.
It is composed of a member 22 composed of a wire or a pillar connected between the members.

In the case of the vibration damping structure 1 shown in FIG. 1, the damper 30 is interposed between the pillar portion 11 of the mega frame 10 and the end of the floor 21 of the sub frame 20, and the sub frame 20 is It is connected to the mega frame 10 via a member 22 and a damper 30. On the other hand, in the case of the vibration control structure 2 of FIG. 2, the auxiliary frames 23 extending in the vertical direction are provided on the floors 21 and the beam portions 12 and 13 in the sub frame 20, and the auxiliary frames 23 that are close to each other are It is connected by a damper 30. The damper 30 is only in the sub frame 20 in the vibration damping structure 2,
No damper is required between the pillar portion 11 of the mega frame 10 and the sub frame 20.

The damper 30 is of a structure such as an oil damper or a friction damper that can appropriately control the damping force, that is, the damping force can be varied, and is transferred from the mega frame 10 to the sub frame 20. Dampens horizontal vibrations.

The vibration damping structures 1 and 2 are different in the installation method of the damper 30, but are different from the mega frame 10 to the sub frame 2.
It is the same as the structure to suppress the vibration that moves to 0,
If the mega frame 10 has one mass point and the sub frame 20 has one mass point, the damping structures 1 and 2 can be represented by a simple model as shown in FIG. Here, the natural frequency ω and the damping constant h in the damping structures 1 and 2 are defined by the following equations.

[0017]

[Equation 1]

The mass ratio μ and the frequency ratio β of the mega frame 10 and the sub frame 20 are defined by the following equations.

[0019]

[Equation 2]

If the mega-frame 10 receives an external wind force and the external wind force is expressed by white noise, the mega-frame 10
The optimum frequency ratio and the damping constant of the sub-frame 20 for minimizing the displacement response of the are given by the following equations.

[0021]

(Equation 3)

However, when obtaining these values, the attenuation of the mega frame 10 was neglected because it was small. Similarly, in order to minimize the acceleration response of the sub-frame 20 which requires a response reduction for habitability, the following equation is an optimum value.

[0023]

[Equation 4]

If the frequency ratio is defined due to structural restrictions, the optimum damping of the subframe 20 differs depending on the purpose. FIG. 4 shows that, when the mass ratio μ is 1, the damping of the sub-frame 20 and the sub-frame 2 that are optimal for minimizing the displacement response of the mega frame 10 are obtained by using the frequency ratio β as a parameter.
Fig. 6 shows a comparison with the damping of the sub frame 20 for minimizing the acceleration response of 0.

In this figure, for example, when the frequency ratio β is 0.2, the damping constant that minimizes the displacement response of the mega frame 10 is 0.33, and the damping constant that minimizes the acceleration response of the sub frame 20 is It is 0.22. That is, if the damping force of the damper 30 is variable, in the wind speed region where habitability is important, the damping constant is set to around 0.22, which emphasizes reduction of the acceleration response of the sub-frame 20, and the structural safety of the mega frame 10 is improved. When the priority is placed, it can be set to around 0.33. As a result, it is possible to achieve both comfort and structural safety.

5 to 8 respectively show the outline of a high-rise building to which the vibration damping structures 3 to 6 according to claims 1 and 3 of the present invention are applied. In each damping structure 3 to 6,
It has the same mega frame 10 and sub frame 20 as the vibration damping structures 1 and 2, and there are the following differences in the installation method of the damper 40 for damping the vibration transferred to the sub frame 20. In this case, the damper 40 is a mega frame 1
It is a structure that mainly suppresses vertical vibrations transferred from 0 to the sub frame 20.

In the vibration damping structure 3, the damper 30 is interposed between the pillar portion 11 of the mega frame 10 and the end of the floor 21 of the sub frame 20, and the sub frame 20 is attached to the member 2 with respect to the mega frame 10.
2 and the damper 40.

In the vibration control structure 4, a column (or wire) 50 penetrates between the beam portions 12 and 13 at the center of each floor 21 constituting the sub frame 20, and the column 50 and each floor 21.
And are connected via a damper 40.

The vibration damping structure 5 includes a core 51 which constitutes an elevator shaft or the like provided in the sub frame 20 and the sub frame 2
Each floor 21 forming 0 is connected via a damper 40.

In the vibration control structure 6, a damper 40 is installed between each floor 21 of the sub frame 20 with a brace 52.

FIG. 9 shows analytical models of the vibration damping structures 3 to 6 and conditions therefor. The mass of each layer of the mega frame 10 is the same, and the sub frame 20 in the mega frame 10 is also modeled by one mass, but each mega layer has the same characteristics. However, the natural frequency of the mega frame 10 is calculated by adding the mass of the sub frame 20 to the mega frame 10.

A comparative study was conducted by inputting seismic motions for both a high-rise building provided with the vibration control structure 3 (or 4 to 6) and a high-rise building not provided with it. FIG. 10 shows a waveform showing the characteristics of the input earthquake motion. This input seismic motion is 1940 El Centro
The component of is moved up and down, and the maximum speed is 25 cm.
It was used after being standardized to be / s. FIG. 11 shows a comparison of acceleration transfer characteristics, and FIG. 12 shows a comparison of displacement response at the top of the mega frame 10 as an example of response results.

Also, the maximum acceleration of the top of the mega frame 10,
FIG. 13 shows a comparison of the maximum displacement and the maximum axial force at the base (lowermost end) of the mega frame with and without the damping structure.

From these comparison results, it is clear that the high-rise building provided with the vibration damping structure has a vibration response reduction effect as compared with the case where it is not provided.

[0035]

As described above, according to the vibration damping structure for a high-rise building of the present invention, the damper is damped against the vibration in at least one of the vertical direction and the horizontal direction. By providing the structure between the mega frame and the sub frame or in the sub frame, it is possible to obtain an effect that it is possible to obtain a vibration damping structure that is effective in both horizontal response reduction and vertical response reduction. Also, if the damping force of the damper is variable, the optimum damper constant can be set according to the purpose, for example, the living performance can be maximized and the safety performance can be maximized. If the natural frequency of is tuned according to the natural frequency of the mega frame, the vibration energy is easily transferred from the mega frame to the sub frame, and the damping effect is enhanced.

[Brief description of drawings]

FIG. 1 is a schematic view of a vibration damping structure of an embodiment according to claims 1 and 2 of the present invention.

FIG. 2 is a modification of the same.

FIG. 3 is a model diagram of a vibration damping structure.

FIG. 4 is a graph comparing the optimum damping of the sub-frame 20 for minimizing the displacement response of the mega-frame 10 with the damping of the sub-frame 20 for minimizing the acceleration response of the sub-frame 20.

FIG. 5 is a schematic view of a vibration damping structure of an embodiment according to claims 1 and 3 of the present invention.

FIG. 6 is a modification of the same.

FIG. 7 is another modification.

FIG. 8 is another modification of the same.

FIG. 9 is an analysis model diagram of a vibration damping structure.

FIG. 10 is a graph showing an input seismic motion waveform used for analysis.

FIG. 11 is a graph showing a comparison of acceleration transfer characteristics.

FIG. 12 is a graph showing a comparison of displacement response waveforms at the top of a mega frame.

FIG. 13 is a table showing a comparison of displacement response waveforms at the top of a mega frame.

[Explanation of symbols]

 1, 2, 3, 4, 5, 6 Damping structure 10 Mega frame 11 Column 20 Sub frame 30, 40 Damper

 ─────────────────────────────────────────────────── ——————————————————————————————————————————— Inventor Quinn Fen United States California 92715 Irvine Whitman Court 7

Claims (3)

[Claims] 1. A mega frame structure arranged along the height direction of a high-rise building, a sub frame structure composed of a plurality of layers of floors, beams, etc. and housed in the mega frame structure, and relocated to the sub frame structure. In a vibration control structure for a high-rise building, which comprises a damper for damping vibration, the mega frame and the sub-frame are configured to suppress the damper against vibration in at least one of a vertical direction and a horizontal direction. A vibration control structure for high-rise buildings, which is characterized by being installed between or within a subframe. 2. A mega frame structure arranged along the height direction of a high-rise building, a sub frame structure composed of a plurality of layers of floors, beams, etc. and housed in the mega frame structure, and relocated to the sub frame structure. A damping structure for a high-rise building, comprising: a damper for damping vibration; wherein a damping force of the damper is variable. 3. A mega frame structure arranged along the height direction of a high-rise building, a sub frame structure composed of a plurality of layers of floors, beams, etc., and housed in the mega frame frame, and transferred to the sub frame structure. A damping structure for a high-rise building, comprising: a damper for damping vibration; wherein a natural frequency of the sub-frame is tuned according to a natural frequency of the mega-frame.