JP2810927B2 - Damping beam - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a damping beam for suppressing vertical vibration of a floor of a structure.

2. Description of the Related Art Conventionally, as a damping beam for suppressing vertical vibration generated on a floor of a structure due to an external force such as an earthquake or mechanical vibration, for example, those shown in FIGS. I have.

FIG. 4 (No. 61-181410) shows the vibration damping performance on the inner surfaces of the flanges 2 and 2 of the beam 1 made of a bent steel plate and having a substantially Σ-shaped cross section. The vibration damping units 5 and 5 each having a high viscoelastic layer 3 sandwiched between two steel plates 4 and 4 are attached. Also,
In the structure shown in FIG. 5 (Japanese Utility Model Application Laid-open No. Sho 57-84218), two viscoelastic layers 6 are sandwiched between the back surfaces of the respective grooved steels 7, 7 and integrated to form an H-shaped cross section. Things.

[Problem to be Solved by the Invention] Both of the above-mentioned vibration damping beams of the above-mentioned two examples use the viscoelastic layers 3, 6 having a high vibration damping performance for the vibration energy generated on the floor of the structure.
Although it is intended to suppress the vibration generated in the structure by absorbing the light, there are the following disadvantages.

In other words, the one shown in FIG. 4 does not apply a large amount of deformation to the viscoelastic body layer 3 and can suppress the micro-vibration, but is not very effective for the large vibration. . In addition, since the cross section of the beam 1 is a special substantially Σ shape, there are disadvantages such as difficulty in molding and processing, and difficulty in designing.

In addition, the one shown in FIG. 5 is effective in absorbing horizontal vibrations, but unsuitable for absorbing vertical vibrations, because the viscoelastic layer 6 is used in a vertical state. Things.

SUMMARY OF THE INVENTION An object of the present invention is to provide an effective damping beam which can solve the above-mentioned disadvantages of the conventional damping beam and can effectively suppress vertical vibration of the floor.

"Means for Solving the Problems" The vibration-damping beam of the present invention is obtained by laminating a plurality of long steel plates and a viscoelastic material to the lower surface of a beam having a composite structure of steel and concrete, It is equipped with a vibration damping device having a structure that is laminated so as to be displaceable.

"Action" Since the damping beam of the present invention has a composite structure of a steel frame and concrete, its own weight is greater than when it is made of pure steel, but its rigidity naturally increases. This is more advantageous than a pure steel structure in terms of suppressing deformation. When the beam vibrates up and down during an earthquake or the like, the upper and lower surfaces of the beam are deformed so as to expand and contract in the longitudinal direction, but in this case, the beam is attached to the lower surface of the beam. The respective steel plates of the vibration damping device are displaced in the longitudinal direction, and the viscoelastic material sandwiched between the steel plates is deformed accordingly, and the deformation absorbs the vibration energy, thereby causing the beam material to be deformed. Vertical vibration is quickly attenuated.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a cross-sectional view of the damping beam of the present embodiment, and FIG. 2 is a diagram showing the lower surface thereof. This damping beam has a structure in which a damping device 11 is provided on the lower surface of a beam member 10. Have been.

The beam member 10 is a composite structure of a steel frame 12 and concrete 13, that is, a partially SRC structure in which only the lower portion of the steel frame 12 having the H-shaped cross section is covered with the concrete 13. The floor slab 14 is supported by the member 10. Reference numeral 15 denotes a stud for integrating the beam member 10 and the floor slab 14. Prestress may be applied to the concrete 13 covering the lower part of the steel frame 12, and in that case, a PC steel material may be buried in the concrete 13 and tensioned.

The lower surface of the beam member 10 (the lower surface of the concrete 13) is a flat surface, on which the vibration damping device 11 is provided. As shown in FIG. 3, the middle part is omitted in FIG. 3, a plurality of (five in the illustrated example) long steel plates 20. Are laminated such that the steel plates 20 can be displaced in the longitudinal direction. That is, five steel plates 20
Of the three, the upper and lower and middle three steel plates are made into one set, the other two steel plates are made into another set, and the steel plates 20 in each set are alternately sandwiched by the viscoelastic material 21. Laminated on
One end of one set of steel plates (right end in FIGS. 2 and 3)
Is fixed to the concrete 13 by bolts 30, and one end (the same, left end) of the other set of steel plates is similarly fixed to the concrete 13 by bolts 31. Reference numeral 32 is a spacer.

Further, the intermediate portion of the vibration damping device 11 is supported by the hanging members 40 so as not to hang down from the lower surface of the beam member 10 and not to restrict the displacement (displacement in the longitudinal direction) with respect to the beam member 10. It has become. The hanger 40 is the first
As shown in FIG. 2 and FIG. 2, a plurality of the vibration damping devices 11 (6
Book) support rods 41 ... and these support rods 41 ...
It is composed of three-sided frame-shaped hanging rods 42 for hanging from the 13 and cushioning materials (rubber cushions or the like) 43 interposed between the hanging rods 42 and the concrete 13.

As shown in FIG. 1, the lowermost steel plate 20 is wider than the other steel plates, and both side edges thereof are bent upward, but this is not a limitation. Not something. In addition, the above-described hanging tool 40 also prevents the middle portion of the vibration damping device 11 from hanging down from the lower surface of the beam member 11,
In addition, any other configuration may be employed as long as it can support the beam 10 in a form that does not restrict displacement.

In the above-mentioned damping beam, the beam 10 is made of steel 12 and concrete 13.
Because of the composite structure, the beam naturally has higher rigidity than when the beam is made of pure steel, and the deformation in the vertical direction is suppressed by itself. When the beam 10 vibrates up and down, the upper and lower portions of the beam 10 are deformed so as to expand and contract. 20 are relatively displaced in the longitudinal direction of the beam member 10, and the viscoelastic members 21 are deformed accordingly, whereby vibration energy is absorbed and the vertical vibration of the beam member 10 is rapidly attenuated. Will be.

Therefore, by employing this damping beam, the vertical vibration of the floor slab 14 can be sufficiently suppressed, and it is suitable for application as a beam of a building in which floor vibration is a particular problem.

As the viscoelastic material 21, for example, a rubber asphalt-based material may be used, and the area of the viscoelastic material, the number of layers,
By appropriately adjusting the thickness and the like, desired attenuation characteristics can be freely obtained.

Further, the beam member 10 in the above embodiment has a partial SRC in which only the lower portion of the steel frame 12 is covered with concrete 13.
However, the form of the beam material may be any appropriate as long as it is a composite structure of steel and concrete, for example, a general SRC structure in which the entire steel frame is covered with concrete, a filled type or a coated type or a filled coated type. A steel pipe concrete structure or the like can be adopted, or a prestress may be introduced as described above.

It is also conceivable to provide the vibration damping device 11 on the upper surface or the side surface instead of the lower surface of the beam member 10, but the vibration damping device
It is difficult to attach the beam 11 to the upper surface of the beam 10 because of the connection with the floor slab 14, and when the beam 11 is provided on the side of the beam 10, the viscoelastic material 21 is attached in the same manner as the conventional one shown in FIG. Are not effective because they are vertical. Therefore, it is preferable to attach the vibration damping device 11 to the lower surface of the beam member 10 as described above.

"Effects of the Invention" As described in detail above, the present invention provides a composite structure of a steel frame and a concrete beam, to which a plurality of long steel plates and a viscoelastic material are attached, Since it is equipped with a vibration damping device of a structure that is laminated so that it can be displaced in the direction, it is more rigid than the case where the beam material is made of pure steel, and the deformation in the vertical direction by itself is In addition to suppressing the vibration, the vibration energy of the beam material is absorbed by the vibration damping device, and the vertical vibration can be rapidly attenuated.

[Brief description of the drawings]

1 to 3 show an embodiment of a damping beam according to the present invention. FIG. 1 is a cross-sectional view, FIG. 2 is a view showing a lower surface thereof, and FIG. FIG. 4 is a side view of the vibration damping device shown as an example. 4 and 5 are perspective views each showing a conventional example of a vibration damper. 10 ... beam material, 11 ... vibration damping device, 12 ... steel frame, 13 ... concrete, 20 ... steel plate, 21 ... viscoelastic material, 40 ... hanging equipment.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuhiko Maebayashi 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Motoichi Kimura 1-1-13, Shimbashi, Minato-ku, Tokyo Higashi Shin Building Co., Ltd. (72) Inventor Shuichi Numano 1-1-13, Shimbashi, Minato-ku, Tokyo In-Toshin Building Co., Ltd. (72) Michio Mizumoto 1-1-13, Shimbashi, Minato-ku, Tokyo (56) References: JP-U 61-181410 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) E04B 1/98 E04C 3/293

Claims (1)

(57) [Claims] 1. A vibration damping structure in which a plurality of long steel plates and a viscoelastic material are attached to a lower surface of a beam having a composite structure of a steel frame and concrete, and are laminated so as to be displaceable in a longitudinal direction. A damping beam characterized by being equipped with a device.