JPH04136539A - Vibration control method for structure - Google Patents

Abstract

PURPOSE:To obtain a wide vibration control frequency band by mounting a vibration controller having the vibration absorbing characteristic corresponding to resonance frequency of a structure, thereafter repeating the process of mounting a vibration controller having the vibration controlling characteristic corresponding to new resonance frequency of the structure after the vibration controller is mounted. CONSTITUTION:When a vibration controller 1 which corresponds to a frequency F0, is mounted close to a point of maximum amplitude of resonance frequency F0 of a structure 2 such as a floor panel, etc., the vibration frequency characteristic curve (b) of the structure 2 after the vibration controller is mounted, has peaks at the frequencies F1, F2 on adjacent both sides of the frequency F0. Vibration absorbers 1a, 1b which correspond to newly induced resonance vibration frequency F1, F2, are further mounted in the neighborhood of the vibration controller 1. Thus, the band width W0 of vibration absorption frequency of the vibration controller 1, the band width W1 of vibration absorption frequency of the vibration controller 1a, the band width W2 of vibration absorption frequency of the vibration controller 1b, can suppress the vibration of the structure 2 by group 7 of the vibration controller having a sufficiently wide band width WX.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an improvement of a vibration suppression method for suppressing vibration by attaching a vibration suppressor to structures such as general industrial machinery and buildings. The present invention relates to a method for suppressing vibrations of a structure that can sufficiently suppress vibrations.

[Prior art]

Curve A (solid line) shown in FIG. 7 shows an example of the vibration frequency characteristic of the structure.

The vibration level of this structure reaches its peak at the resonant vibration frequency f of the structure, as shown in this figure.

Generally, as a method for suppressing the vibration of such a structure, a vibration suppressor having vibration absorption characteristics that matches the resonant vibration frequency f of the structure is placed near the maximum amplitude point of the resonant vibration frequency f of the structure. known to be installed.

Incidentally, FIGS. 6(a) and 6(a) show an example of the vibration suppressor disclosed in Japanese Patent Application Laid-Open No. 110938/1983.

This vibration suppressor 51 includes a plate spring 52. Mounting bracket 53, weight 54. It is made of a viscoelastic body or a viscous body 55 (hereinafter simply referred to as a viscoelastic body), and is attached so that the leaf spring 52 is perpendicular to the vibration direction (arrow X) of the structure 56.

In this vibration suppressing device, the plate spring 52 vibrates due to the vibration of the structure 56, and the vibration energy of the structure 56 is reduced by the shearing deformation of the viscoelastic body 55 accompanying the deformation of the plate spring 52 due to the vibration. The resonance vibration frequency f of the structure 56 is converted into thermal energy and released into the atmosphere.
, vibrations in the vicinity are suppressed.

Curve B (broken line) shown in FIG. 7 shows the vibration frequency characteristic of the structure 56 after vibration control by the conventional vibration suppression device.

As can be seen from this figure, this vibration frequency characteristic has frequencies r, , r on both sides of the resonant vibration frequency f.

It has a peak at .

This is because since the vibration damping frequency bandwidth (W in FIG. 7) of the vibration suppressor is narrow, only vibration components near the resonant vibration frequency f0 of the structure are suppressed.

By the way, when the mass of furniture, etc. is added to the structure (for example, a floor panel), the vibration system of the structure changes, and the resonant vibration frequency of the structure changes from f0 to f0. Soften.

[Problem to be solved by the invention]

Therefore, in the conventional vibration suppression method described above, as shown in vibration characteristic surface 1#c (-dotted chain line) in FIG.

The resonant vibration frequency f8 of the shifted structure is.

If the vibration absorption frequency is outside the bandwidth W of the vibration suppressor, there is a drawback that the vibration of the structure cannot be sufficiently suppressed.

By the way, one possible way to solve the above problem is to widen the bandwidth of the vibration absorption frequency of the vibration suppressor, but if the bandwidth of the vibration suppressor is widened, the level of vibration absorption will usually become insufficient.

Another possibility is to attach multiple vibration suppressors to the structure, but even if multiple vibration suppressors with the same vibration absorption properties are installed, only the vibration components near the resonant vibration frequency of the structure will be controlled as described above. However, the effect is not sufficient.

Therefore, the present invention not only can easily control harmful vibrations such as fI and ft, but also has a wide range of functions that can sufficiently suppress the vibration of the structure even if the vibration system of the structure changes due to the addition of mass. The purpose of this invention is to provide a vibration suppression method that can obtain a vibration absorption frequency band.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a vibration suppressing method for suppressing vibration by attaching a vibration suppressor to a structure such as a building, and provides a method for suppressing vibrations that has a vibration absorption characteristic corresponding to the resonant vibration frequency of the structure. A procedure for attaching a vibration suppressor to the structure, and also attaching to the structure a vibration suppressor having vibration absorption characteristics corresponding to a new resonant vibration frequency of the structure induced in the structure after the vibration suppressor is installed. The present invention is configured as a vibration suppression method for a structure, characterized in that the above steps are repeated at least once.

〔Example〕

Hereinafter, nine embodiments embodying the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention.

Note that the following example is an example embodying the present invention, and 1
It is not intended to limit the technical scope of the present invention.

FIG. 1 is an explanatory schematic diagram showing an example of a vibration suppressing method for a structure according to an embodiment of the present invention, FIG. 2 is a cross-sectional schematic diagram showing an example of a vibration suppressor used in the vibration suppressing method, and FIG. Figure (al
, (b), and (c) are schematic vibration characteristic graphs showing each process of the vibration suppression state of the structure by the same vibration suppression method, and Figure 4 is an example of the vibration characteristics of the structure shown in Figure 3 above. Fig. 5 is an actual measurement graph showing an example of the vibration characteristics of the same structure when a mass is added to the same structure.

The song IIAa (actual, *) shown in FIG. 3(a) is a schematic representation of the curve A shown in FIG. '7.

That is, the vibration characteristic curve a of this structure has a resonant vibration frequency F
The vibration level of the same structure reaches its peak at .

Also in the vibration suppression method for a structure according to this embodiment, as shown in FIG. 1, the resonant vibration frequency F0 of the structure 2 such as a floor panel is A vibration suppressor 1 compatible with F is installed.

Therefore, the vibration suppressor 1 is attached to the structure 2 later.
The vibration frequency characteristic curve b (broken line in FIG. 3 (b)) also has peaks at frequencies F+ and Ft on both sides of the resonant vibration frequency F0, as in the conventional case.

The above-mentioned vibration suppressor 1 used in this method of suppressing vibrations of a structure includes a plate spring 4 having a weight of 3 degrees, for example, as shown in FIG. It is equipped with mounting brackets 5, etc., as shown in FIGS. 6(a) and (b) above.
The vibration suppressor shown in FIG. One point is common to both.

However, in this structure vibration suppression method, the newly induced resonant vibration frequencies F, , F, of the structure 2,
Vibration suppressor compatible with 1. ．． 1% is further different from the conventional one in that it is attached near the vibration suppressor 1, as shown in FIG. still.

The above vibration suppressor 1. ．． 1. has the same configuration as the vibration suppressor 1 shown in FIG. 2, and differs only in its vibration absorption vibration frequency characteristics.

The curve C (-points 11i, l1l) shown in FIG. 3(1)) corresponds to the above vibration suppressor], 1. ,1. The mounting diagram schematically shows an example of the vibration frequency characteristics of the structure 2 described above.

As can be seen from this figure, in this structure vibration suppression method, the vibration absorption frequency bandwidth W0. Vibration suppressor 1. Bandwidth of vibration absorption frequency W,.

The vibration suppressor group 7 (FIG. 1), which has a sufficient absorption vibration level and a wide bandwidth Ww of the absorption frequency of the vibration suppressor L, can reduce the vibration of the structure 2.
vibration can be suppressed.

FIG. 4 shows actual data curves of the vibration characteristics of the structure 2 corresponding to the curves 3 and 3 in FIG. 3 (b), respectively.
C, is shown.

Further, FIG. 5 shows an actual data curve a+ (solid line) of the vibration characteristics of the structure 2 corresponding to the curve a in FIG. 3(a),
The actual data curve CI (-dotted chain line) corresponding to the song wAc in Fig. 3, etc. shown in Fig. 4 above, and the vibration characteristics of the structure 2 when the mass of furniture etc. is added to the structure 2. The actual data song *a+ (broken line) is shown.

As can be seen from this figure, in this structure vibration suppression method, even if mass is added to the structure 2 as described above, the vibration suppressor group 7 having the wide vibration absorption bandwidth W6 allows the structure 2 to be 2 can be sufficiently suppressed.

That is, in this vibration suppression method, even if the vibration system of the structure 2 changes due to the addition of the mass and the resonant vibration frequency of the structure 2 shifts, the vibration of the structure 2 cannot be sufficiently suppressed. can.

In the above embodiment, the vibration suppressors 11 and 1. are both installed near the vibration suppressor 1, but naturally, the same vibration suppressor 1. and 1. You may also attach it.

Yet again. The above vibration suppressor 1.1. ．． 1. The attachment is later induced at the resonant vibration frequency Fs of the new structure 2.
, F-, Fs, F6 (Fig. 3(b), (C
) A vibration suppressor having vibration absorption characteristics conforming to (see ) may be further attached to the structure 2 to suppress vibrations of the structure 2.

The curve e (broken line) in FIG. 3(C) schematically shows an example of the vibration frequency characteristic of the structure 2 after the above-mentioned vibration suppressor is installed.

As can be seen from this figure, the new vibration suppressor group has a vibration absorption bandwidth W that is wider than the vibration absorption bandwidth W8 of the vibration suppressor group 7.

Thereafter, by repeating the above procedure, the vibration absorption bandwidth can be further widened.

〔Effect of the invention〕

In the vibration suppression method of the present invention, in which a vibration suppressor is attached to a structure such as a building to suppress the vibration thereof, a vibration suppressor having vibration absorption characteristics corresponding to the resonant vibration frequency of the structure is attached to the structure. At the same time, the procedure for attaching a vibration suppressor having vibration absorption characteristics corresponding to the new resonant vibration frequency of the structure induced in the structure after the vibration suppressor is attached to the structure is repeated at least once. A method for suppressing vibration of a structure is provided.

Therefore, according to the vibration suppression method for a structure, it is possible to attenuate high-order vibrations with a simple operation, and by widening the vibration absorption bandwidth W11, the vibration system of the structure changes somewhat due to the addition of mass, etc. However, the vibration of the same structure can be sufficiently suppressed.

[Brief explanation of drawings]

FIG. 1 is an explanatory schematic diagram showing an example of a vibration suppressing method for a structure according to an embodiment of the present invention, FIG. 2 is a cross-sectional schematic diagram showing an example of a vibration suppressor used in the vibration suppressing method, and FIG. Diagram (a)
, (b), and (C) are schematic vibration characteristic graphs showing each process of the vibration suppression state of the structure by the same vibration suppression method, and Fig. 4 is a vibration characteristic graph of the structure shown in Fig. 3 (b) above. An example of an actual measurement graph. Figure 5 is an actual measurement graph showing an example of the vibration characteristics of the same structure when mass is added to the same structure.
Figures 6 (a) and (b) are front and side views showing an example of a vibration suppressor, respectively, and Figure 7 shows the vibration frequency characteristics of the same structure when a conventional structure vibration suppression method is used. This is an example of an actual measurement graph. [Explanation of symbols] 1.1-, 1b... Vibration suppressor 2... Structure F+ Fz Fx F-, Fs, F4... Resonant vibration frequency

Claims (1)

[Scope of Claims] 1. A vibration suppressing method in which a vibration suppressor is attached to a structure such as a building to suppress its vibration, which includes a vibration suppressor having vibration absorption characteristics corresponding to the resonant vibration frequency of the structure. At least one step of attaching to the structure a vibration suppressor having vibration absorption characteristics corresponding to a new resonant vibration frequency of the structure induced in the structure after the vibration suppressor is attached. A method for suppressing vibrations of a structure, characterized by repeating the above steps.