JPH05156839A - Vibration-restraint frame structure - Google Patents

Abstract

PURPOSE:To provide vibration-restraint frame structure which has a high design freedom degree and acts effectively even against vibration whose vibration number is large, in low frequency and has no need of being provided with a wall for restraining vibration. CONSTITUTION:Pieces of low yielding point steel acting as damper materials 2 are attached in layer to the flanges 1a of steel frame members 1 constituting beams B and pillars A. And pressing plates 3 that restrain surface outside deformation generated when the plasticity of the low yielding point steel is conducted on a pulling side and then distortion is going to return to a compression side, are attached in layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a beam column member of a frame of a steel frame structure or a steel frame reinforced concrete structure, and relates to a vibration control frame structure for reducing vibration due to earthquake, wind or the like.

[0002]

2. Description of the Related Art Conventionally, in this type of structure, as shown in FIG. 8, a space is provided between the upper part of a wall a and a beam b, and a damper c such as a friction damper or a lead damper is interposed at the same space. Then, the interlayer deformation of the building is caused mainly between the upper part of the wall a and the beam b, and the deformation is absorbed as damping energy by a friction damper or a lead damper, or a damping material is applied to the beam b, the pillar d, etc. In many cases, they are attached or vibration damping steel plates are used for the beams b, columns d and the like.

[0003]

However, in the former method, it is necessary to properly dispose the wall, and therefore, there are design restrictions. Further, in the latter, damping property is produced as a material property of the damping material and the damping steel plate. For example, when a viscoelastic damping material is used, vibration energy is absorbed as damping energy generated by its viscosity. This damping property is often effective for high-frequency vibrations such as sound, and is often not effective for low-frequency vibrations such as earthquakes and winds.

The present invention has been proposed in view of the above-mentioned problems of the prior art. The object of the present invention is to effectively act on vibrations of large amplitude at low frequencies and to suppress vibrations. The point is to provide a damping frame structure that does not require a wall and has a high degree of freedom in design.

[0005]

In order to achieve the above-mentioned object, a damping frame structure according to the present invention comprises a low yield point steel layered on a flange of a beam or a column as a damper material. The low-yield-point steel is formed by layering a pressing plate that restrains out-of-plane deformation that occurs when strain is returned to the compression side after the low yield point steel is plasticized on the tensile side.

[0006]

The damping frame structure according to the present invention, as described above,
The low-yield-point steel, which is layered as a damper material on the flanges of walls and columns, yields with a small strain and then plastically deforms. Therefore, when a beam or column vibrates due to an earthquake or wind, even if the beam or column vibrates within the elastic deformation, the low yield point steel as a damper material repeats plastic deformation, and its hysteresis energy causes the vibration energy of the building to rise. To reduce building vibration. Even if the beam or column is deformed to the plastic region, the same beam,
The low-yield-point steel layered on the columns becomes plastic and exhibits the same effect.

Thus, when the holding plate is not layered on the low yield point steel, when the low yield point steel is plasticized on the tensile side and then the strain is returned to the compression side, the deformation occurs out of plane. According to the present invention, since the holding plate is layered on the low yield point steel as described above, the holding plate constrains the deformation of the low yield point steel. It is a thing.

[0008]

The present invention will be described below with reference to the illustrated embodiments. FIG. 2 shows that when the low yield point steel as the damper material 2 and the damper material 2 made of the same low yield point steel undergo a large deformation as described later on the flange 1a of the steel member 1 having the H-shaped cross section, the out-of-plane deformation is caused. A holding plate 3 made of high-tensile steel for preventing the occurrence of the occurrence is layered and fixed by bolts 4.

FIG. 3 shows that when the low yield point steel as the damper material 2 and the low yield point steel on the outer peripheral surface of the box steel 5 undergo a large deformation as described below, the out-of-plane deformation of the low yield point steel is suppressed. A pressing plate 3 made of high-strength steel is layered and secured with bolts 4. Figure 4 shows the inner surface of the box steel 5.
When the low-yield-point steel as the damper material 2 and the low-yield-point steel cause a large deformation as described below, a holding plate 3 made of high-tensile steel is laminated to prevent out-of-plane deformation, and welding is performed. It has been w.

FIG. 1 shows an embodiment of a vibration-damping frame structure according to the present invention, which has a low yield point on the upper and lower flanges 1a of an H-shaped member 1 which constitutes a column A of each layer of a three-story steel frame structure. A damper material 2 made of steel is attached, and a holding plate 3 made of high-tensile steel is layered on the damper material 2. B in the figure is a beam. FIG. 5 shows a deformed state when a bending moment M is applied. When the building vibrates due to an earthquake or wind, bending deformation occurs in the H-shaped member 1 forming the pillar A, and the upper flange as shown in FIG. When a bending moment M is applied to 1a to cause deformation to some extent, the upper flange 1a elastically deforms as shown in FIG. 5B, but the damper material 2 of the upper flange 1a plastically deforms. If the holding plate 3 is not provided, the upper flange 1a is plastically deformed as shown in FIG. 6B, and if the holding plate 3 is not provided, the upper flange A ₁ is On the compression side, the damper material 2 may be deformed out of the plane, and the compression force may not increase as shown in FIG.

However, when the pressing plate 3 is layered on the damper material 2, the damper material 2 draws a stable hysteresis loop without being deformed out of plane. When subjected to positive and negative repeated bending, positive and negative plastic deformation occurs, and this plastic deformation absorbs as hysteretic absorption energy, which reduces building vibration.

[0012]

As described above, according to the present invention, the low yield point steel is layered on the flanges of beams and columns as a damper material, and the low yield point steel is yielded to absorb the vibration of the building. It absorbs as energy and reduces the vibration of the building. According to the present invention, by attaching a low yield point steel as a damper material to the structural members of the beam and the pillar,
There is no need to install a vibration control wall in the plan, which increases the degree of freedom in design. Further, by adjusting the amount of the low yield point steel constituting the damper material, it is possible to effectively exhibit the vibration damping effect even for vibrations of large amplitude at low frequencies such as wind and earthquake.

Further, according to the present invention, as described above, by layering the holding plate on the low yield point steel, the out-of-plane deformation that occurs when the low yield point steel is plasticized on the tensile side is restrained. Then, the damper material draws a stable history loop. When subjected to repeated positive and negative bending, positive and negative plastic deformation occurs, but due to this plastic deformation, it is absorbed as hysteresis absorption energy, and the vibration of the building becomes small.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a damping frame structure according to the present invention.

FIG. 2 is a vertical cross-sectional view showing an example of H-section steel used in the frame structure of the present invention.

FIG. 3 is a longitudinal sectional view showing an example of a box steel used in the frame structure of the present invention.

FIG. 4 is a vertical sectional view showing another embodiment of the box steel.

5 (a) and (b) are front views showing a case where the upper flange of the H-shaped cross-section material is subjected to a bending moment and is deformed to some extent, and in addition, the stress of the upper flange and the upper damper material at that time. FIG.

6 (a) and 6 (b) are front views showing the case where the upper flange side of the H-shaped cross-section material undergoes compressive deformation and the upper damper material undergoes out-of-plane deformation. It is a stress-deformation figure.

FIG. 7 is a front view showing a modification of an H-shaped cross-section member including a pressing plate.

FIG. 8 is a front view showing a conventional damping frame.

[Explanation of symbols]

 A Pillar B Beam 1 Steel frame member 1a Flange 2 Damper material 3 Holding plate 4 Bolt 5 Box steel w Welding

Claims (1)

[Claims] 1. A low yield point steel is layered as a damper material on a flange of a beam or a column, and the strain is returned to the compression side after the low yield point steel is plasticized on the tensile side. A vibration-damping frame structure characterized in that it is formed by layering a holding plate for restraining out-of-plane deformation that occurs when an attempt is made.