JP2715710B2 - Eccentric brace structure with vibration suppression function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentric brace structure having a vibration control function.

[0002]

2. Description of the Related Art In middle- and high-rise buildings, a building frame using a brace structure is widely used as a resistance element against a horizontal force such as an earthquake or wind. However, with this brace frame, the shear stiffness of each layer is extremely high, so the rigidity of the entire building is increased and the input of earthquakes is increased, and adverse effects such as the ineffective use of the ramen frame used in combination with the brace frame. It can happen.

Therefore, in recent years, an eccentric brace capable of adding a stable elasto-plastic behavior to a building has been proposed as a structure in which the axes of the columns, beams and braces are not aligned with each other, and have been put to practical use. I have. By the way, as typical examples of the eccentric brace, as shown in FIG. 5, a Y-shaped brace (A), a double Y-brace (B),
(C) There is an improved C-shaped brace or the like. In each case, the upper end of the mountain-shaped brace 1 or the roof-shaped brace 2 and the beam 3 are connected via a vertical bundle 4.

The advantages of using the eccentric brace structure include the following: the brace members 1 and 2 do not buckle; the bundle member 4 yields first; Absorbing energy and minimizing damage to major structural members.

[0005]

An eccentric brace structure of this type is disclosed, for example, in Japanese Patent Application Laid-Open No. 63-67382. In this eccentric brace structure,
The rigidity and proof stress are adjusted by appropriately setting the length, cross-sectional shape, and cross-sectional area of the bundle material that gives the elasto-plastic deformation behavior, and the seismic energy is absorbed (damper effect). For this reason, the vibration control region at the time of absorbing the seismic energy is naturally determined by the length, cross-sectional shape, and cross-sectional area preset for the bundle.

Further, a general X-shaped brace structure,
The one that actively aimed at the damper effect was the actual opening 1-988
No. 69 proposes this. That is, this X-shaped brace structure has a structure in which a damping material is interposed at the brace intersection, the yielding of the damping material is caused by shear deformation caused by the deformation of the brace, and the hysteresis obtained at this time is used as a damper. Has become. However, even when the damping material is interposed in this way, its damping region is specified, and its effectiveness is exerted mainly only during large deformation.

As described above, conventionally, when designing a brace frame, a large earthquake is assumed to determine the vibration control region. Therefore, the damper effect does not act on the vibration control in a relatively small amplitude region. However, there is a problem that the vibration is directly input to the building.

In view of the above-mentioned problems, the present invention exerts a damper effect in a wide range of vibration from small amplitude to large amplitude, and can greatly expand the damping area of a building. An object is to provide an eccentric brace structure having a function.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a method in which an upper floor beam is provided in a space defined by upper and lower floor beams and columns connecting these beams in a vertical direction. In the eccentric brace structure, the upper end of the brace erected diagonally upward from the beam on the lower floor is connected to the lower end of the vertically suspended bundle so that the axes of the columns, beams and braces do not coincide with each other. Surrounding the bundle with the superplastic material and the outer periphery of the superplastic material.
And steel plates .

[0010]

[0011]

[0012]

[0013]

According to the eccentric brace structure having the vibration damping function of the present invention having the above-described structure, a large shear deformation occurs in the bundle material provided at the upper end of the brace when vibration is input, and the shear material causes the bundle material to be damped. The effect is exhibited, and the input vibration can be reduced. At this time, the bundle material has rigidity and proof stress.
Is composed of different superplastic materials and steel plates,
Superplastic material with high strength and high strength can be easily plastically deformed by external force.
Exhibits the damper effect in the vibration region with extremely small amplitude
On the other hand, high-rigidity, low-strength steel sheets surrounding this superplastic material
Vibration area with large amplitude compared to the vibration damping area of the superplastic material
It will exhibit a damper effect in the region. So the amplitude
Performing a wide range of different vibrations and strong winds
In particular, the vibration control region is improved by plastic deformation of the superplastic material.
Because it can be set to a smaller amplitude side,
Vibration can greatly contribute to its damping effect
Wear.

Further, the bundle may be constituted by arranging a plurality of members having different rigidities and proof strengths side by side, surrounding a member having a high stiffness and a low proof strength with a member having a low stiffness and a high proof strength, or forming a member having a low rigidity and a high proof strength. By configuring the proof member by surrounding it with a member having high rigidity and low proof strength, the configuration can be simplified.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 3 show an eccentric brace structure 10 having a vibration damping function according to an embodiment of the present invention. FIG. 1 is a perspective view of a main part of the eccentric brace, and FIG. 2 is a building using the eccentric brace structure of the present invention. FIG. 3 is a hysteresis characteristic diagram showing the elasto-plastic performance of each member constituting the bundle of the eccentric brace of the present invention.

That is, the eccentric brace 12 applied to the brace structure 10 of the present embodiment is the Y-shaped brace shown in FIG. 5A, and as shown in FIG.
Is provided between a pair of columns 18, 18 erected between a beam 14 on the lower floor and a beam 16 on the immediately higher floor.
Upward from the lower end of the pair of braces 20, 20
Are tilted so as to form a mountain shape, and the upper end of each is
6 at a position which is appropriately separated downward. The upper end joints of the braces 20, 20 are joined to the beams 16 via bundles 22 arranged vertically.

As shown in FIG. 1, the bundle member 22 is composed of a first steel member 24 and a second steel member 26 having different rigidities and proof stresses. In this embodiment, a link 28 is provided at the upper end joint of the braces 20, 20, and the first steel 24 is disposed at the center of the link 28, and the first steel 24 is provided on both sides of the first steel 24. Two steel materials 26 are arranged, and the first and second steel materials 24 and 26 are alternately arranged in parallel.

As the first steel material 24, a material having high rigidity and small proof strength is selected, and the second steel material 26 is selected.
As the material, a material having lower rigidity and higher proof strength than the first steel material 24 is selected.

With the above configuration, in the eccentric brace structure 10 of the present embodiment, when a lateral force acts on the eccentric brace 12 due to seismic force or strong wind, the bundle member 22, First steel material 24 and second steel material 26
Large shear deformation occurs. Then, these first steel materials 2
4, the second steel material 26 is deformed to exert a damper effect, and the building can be damped. At this time, the first and second steel materials 24 and 26 have different elasto-plastic performances due to differences in rigidity and proof stress, and a region where the damper effect is exhibited, that is, the vibration damping obtained by the respective steel materials 24 and 26. The area is different.

That is, the hysteresis characteristic indicating the elasto-plastic performance of the bundle 22 is shown in FIG. 3, and the first steel material 24 having high rigidity and low proof strength has the hysteresis characteristic A shown by a broken line in FIG. The second steel material 26 having low rigidity and high proof strength has a hysteresis characteristic shown by a solid line in FIG. That is, the first steel material 2 having high rigidity
No. 4 has a small proof stress and exhibits a large damper effect against small-amplitude vibration, while the second steel material 26 with low rigidity has a large proof stress and exhibits a large damper effect against large-amplitude vibration.

In the present embodiment having the above-described structure, the bundle member 22 of the eccentric brace 12 is composed of the first steel member 24 and the second steel member 26 having different rigidities and proof strengths. In this case, the vibration damping area by the damper action is secured separately, so that a wide range of vibration damping from a small earthquake to a large earthquake and a strong wind can be damped.

The first steel material 24 and the second steel material 26 can be set in a region where the damper effect can be efficiently exhibited by appropriately selecting the rigidity and the proof strength in advance.

FIG. 4 shows another embodiment, in which the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

That is, in this embodiment, a superplastic material 30 such as lead or a superplastic alloy is provided on the link portion 28 and the outer periphery of the superplastic material 30 is surrounded by the steel plate 32 so that the bundle material 22 is formed. Configure.

Accordingly, in this embodiment, the superplastic material 30 having low rigidity and high proof stress is easily plastically deformed by an external force.
The region where the superplastic material 30 exerts the damper effect is a vibration region having a remarkably small amplitude. Further, since the steel plate 32 surrounding the superplastic material 30 has high rigidity and low proof stress, the steel plate 32 exhibits a damper effect in a vibration region having a larger amplitude than the vibration damping region of the superplastic material 30.

Therefore, even in this embodiment, since the bundle 22 is composed of the superplastic material 30 and the steel plate 32 having different stiffness and proof strength, it is possible to perform vibration control over a wide range of different amplitudes and strong wind. it can. In particular, since the vibration damping region can be set to a smaller amplitude side by plastic deformation of the superplastic material 30, it can greatly contribute to the vibration damping effect even in the case of slight earthquake vibration.

In the above embodiment, the outer periphery of the superplastic material 30 having a low rigidity and a high proof strength is configured to be surrounded by a steel plate 32 having a high rigidity and a low proof strength. May be configured to be surrounded by a member having low rigidity and high yield strength, and it is needless to say that the same operation and effect can be exhibited.

In each of the above embodiments, the case where the present invention is applied to a Y-shaped brace is disclosed. However, the present invention is not limited to this, and other examples shown in FIGS. Of course, the present invention can be applied to an eccentric brace structure.

[0029]

As described above, in the eccentric brace structure having the vibration damping function according to the first aspect of the present invention, the bundle material having the eccentric brace structure is made of a superplastic material having different rigidity and proof stress.
Since it is composed of a steel plate, a damper effect area for damping is assigned to each member, and the damping possible area can be expanded to a wide range from a large amplitude area to a small amplitude area . Smaller vibration suppression area due to plastic deformation of superplastic material
Because it can be set on the amplitude side, slight ground vibration
Can greatly contribute to its damping effect.
You.

[0030]

[Brief description of the drawings]

FIG. 1 is a perspective view of an essential part showing an embodiment of an eccentric brace structure to which a vibration damping device according to the present invention is applied.

FIG. 2 is a schematic configuration diagram showing a skeleton of a building using the eccentric brace structure according to the present invention.

FIG. 3 is a hysteresis characteristic diagram showing the elasto-plastic properties of a bundle of eccentric braces according to the present invention.

FIG. 4 is a perspective view of a main part corresponding to FIG. 1, showing another embodiment of the present invention.

FIG. 5 is a schematic configuration diagram showing a general example of an eccentric brace.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Vibration suppression device 12 Eccentric brace 14 Beam on lower floor 16 Beam on upper floor 18 Column 20 Brace 22 Bundle material 24 First steel material 26 Second steel material 30 Superplastic material 32 Steel material

Claims (1)

(57) [Claims] In a space defined by upper and lower floor beams and columns connecting these beams in a vertical direction, a lower end of a bundle material suspended from an upper floor beam is connected to a lower floor beam by a lower floor beam. In an eccentric brace structure in which the upper ends of the braces erected diagonally upward are joined so that the axes of the columns, beams, and braces do not coincide with each other, the bundle material is made of a superplastic material and a superplastic material. Surround the perimeter
Eccentric brace structure with a vibration damping function characterized by comprising a steel plate .