JPH0381476A - Method for controlling vibration of structure - Google Patents

Abstract

PURPOSE:To control vibration caused by wind, earthquake etc. by disposing a high speed rotating body on the top of a structure, and when the body is rotated and deformed by an external force caused by earthquake or the like, sensing it and actuating the body to generate moment in the direction opposite to the external force. CONSTITUTION:Two damping devices 10a, 11b comprise respective rotation axes 16a, 16b and rotating bodies 17a, 17b. The damping devices are each rotatably arranged with a phase angle of 90 deg. and supported on an X-axis direction supporting stand 11a, 12a and a Y-axis direction supporting stand 11b, 12b, both of which are provided on the top of a structure 1. When the damping devices thus arranged are rotated and actuated, the damping device 10a acts against an external force exerted thereon in the X-axis direction, while the damping device 10b acts against an external force in the Y-axis direction. Both damping devices 10a, 10b act against external forces coming from other than the X-axis and Y-axis, and so the damping effect is obtained in all directions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for controlling vibrations caused by wind and earthquakes in a structure.

[Conventional technology]

Conventionally, as a control method when structures such as high-rise buildings and towers vibrate due to wind or earthquakes, for example, a container containing a liquid is installed on the roof of the structure, and the inertia force generated when this liquid flows is used. A method using viscous force and viscous force is known.

[Problems to be Solved by the Invention] In the conventional vibration control method using a liquid container, the natural period of the liquid container itself is determined by the size of the container and the depth of the liquid. The drawback is that vibrations cannot be effectively controlled.

This invention was made to eliminate the above-mentioned drawbacks, and is based on the principle of angular momentum when an external force acts on a rotating body rotating at high speed, and achieves high precision without using special control means. It is an object of the present invention to provide a method capable of controlling vibrations in a wide period range.

[Means to solve the problem]

In order to achieve the above object, in this invention, a rotating body installed inside a structure is rotated at high speed around a rotation axis having a predetermined angle with respect to the direction of external force. Also, when a rotating body undergoes rotational deformation with an angular velocity Ω, a moment Ml is generated around an axis perpendicular to this angular velocity vector, and this moment Ml
By generating an angular velocity Ω2 around the axis of the rotating body, a moment M2 is generated around the Y-axis perpendicular to this angular velocity vector, and this moment M2 causes rotational deformation in the direction opposite to the rotational deformation of the structure. The structure is such that the vibration is controlled by

In high-rise structures where bending deformation is predominant due to external forces, rotation in the opposite direction to the rotational deformation due to bending of the structure can be achieved by rotating at least a rotating body installed on the roof floor at high speed around a vertical axis of rotation. Deformation occurs.

In a high-rise structure having a continuous wall, it is preferable to rotate a rotating body at high speed around a vertical axis of rotation in at least one of the top layer and the middle layer of the continuous wall.

In low- and medium-rise structures where shear deformation is predominant due to external forces, rotating a rotating body installed on the beam at high speed around a vertical axis of rotation can eliminate rotational deformation caused in the beam due to shear deformation of the structure. rotational deformation occurs in the opposite direction.

Similarly, in low-to-medium-rise structures where shear deformation is predominant due to external forces, rotating bodies installed on the sides of columns are rotated at high speed around horizontal rotation axes. Rotational deformation occurs in the opposite direction to the rotational deformation that occurred in the column.

The principle of the vibration damping mechanism used in the method of this invention will be explained based on the drawings.

Figure 1 shows the state of deformation when wind and earthquakes are applied to the high-rise structure 1. At the top of the high-rise structure 1, horizontal deformation δ due to bending and rotational deformation θ are predominant. .

In this invention, as shown in FIG. 2, rotational deformation θ,
A moment M2 is generated in the direction of the arrow shown in the figure, which is opposite to the moment M! The horizontal deformation δ caused by
and rotational deformation θ.

This is to cancel and eliminate the

3 to 5 show an example of a vibration damping device used in the method of the present invention and its operating principle.

This vibration damping device 10 horizontally supports a beam 13.14 rotatable around an axis connecting the support stands 11 and 12 on a support stand 11.12 installed at the top of a structure 1, for example. A disk-shaped rotating body 17 is disposed within the frame 15 and rotatably supports a rotating shaft 16 on the vertical center line of the frame 15, which has both diametrical ends attached to the frame 14.
is attached to a rotating shaft 16, and a drive mechanism (not shown) causes the rotating body 17 to rotate at high speed in the direction of the arrow in the drawing.

In the vibration damping device 10, the direction passing through the support bases 11 and 12 with respect to the rotation axis 16 of the rotating body 17 is the X axis, and the direction perpendicular to this is the Y axis.

Now, suppose that vibration due to an external force is applied to the structure 1 from the X-axis direction, and as a result of the rotational deformation θA (angular velocity Ω1) caused in the structure 1 due to this vibration, the rotating body 17 of the allocation device Since the same angular velocity Ω as that of the structure is given, a moment M in the direction of the arrow shown in FIG. 4 is generated around the X-axis orthogonal to this angular velocity vector. Rotating body 1
7 is the angular velocity Ω around the X axis due to this moment M +
2, so Y that is orthogonal to this angular velocity vector
A moment M2 in the direction of the arrow shown in FIG. 5 is generated around the axis. This M! acts on the structure 1 as a vertical force (couple) of N, N through the support bases 11 and 12.

The moment M2 generated in this way causes a horizontal deformation δ3 and a rotational deformation in the direction opposite to the horizontal deformation δ and rotational deformation θ4 of the structure 1, so δ1 cancels out δ and suppresses vibration. Ru.

The above operation occurs when the bending deformation of the structure 1 occurs in the forward direction shown in FIG. By the same principle, the moment M around the X axis due to the angular velocity Ω around the Y axis.

and the moment M2 of Y'Nlr@ due to the angular velocity Ω2 around the X axis are repeatedly generated in both the forward and reverse directions according to the rotational deformation of the structure.

Next, when the above vibration allocation device is installed in a high-rise structure with a height of h, calculate the weight ratio between the structure and the rotating body required to obtain a damping effect based on the principle of the angular momentum of the rotating body. The calculation yields the following result:

First, consider the case where an external force P due to wind is applied. For convenience of calculation, assume that this external force P concentrates on the top of the structure 1 and acts in the X-axis direction (Figure 6). Direction of vibration of the structure. Let I8 be the moment of inertia of area, and let E be Young's modulus.
Horizontal deformation δ due to bending and rotational deformation θ caused by external force P at the top of the structure.

are respectively expressed by the following formulas.

δA=P-h3/3・E-1,...(1) θA
-P-h! /2・E'1m ・・・・・・
(2) Considering that the vibration that occurs when the external force P is released in this state is not attenuated, the time when the external force P is released is 1 = 0.
, the circular frequency of the structure is ω, (ω3=2π/T, T is the natural period), then the horizontal deformation X(t
), horizontal velocity X<t), rotation angle θ (t), and one rotation angular velocity θA (t) are given by the following equations, respectively.

X(t)-1'h3cos(ωst)/34-in
""43)×(t)=-P-h'-ω5sin
(ωst) I3・E-1+ ・・・・・・(4) θa(
t) = P-h”cos(ωst)I2・e-xyr
・”-(s)fJ a(t) =-P-h2-
ω3sin(ωat) I2・E−rs”・=(6) Since σA (t) in the above equation (6) is the angular velocity Ω accompanying the rotational deformation mentioned above, Ω+ =−1”h'ω3sin(ωst ) / 244m
(7) This angular velocity Ω1 is applied around the Y-axis of the rotating body, and generates a moment M shown in (8) 2 around the X-axis.

M+””It ・ω・Ω1 ・・・・
(8) Here, 1+=mass rotational moment of inertia about the rotational axis of the rotating body ω=rotational angular velocity of the rotating body This moment M causes the rotating body and the frame to rotate around the X-axis. 'The balance at this time is I2・Tei2=Ml...
...(9) However, ! '2g = Angular acceleration of the rotating body and the entire frame around the X-axis I2 = Mass rotational inertia moment of the rotating body and the entire frame around the X-axis Here, from equations (7), (8), and (9), fl[l )
The formula is obtained.

6t =-1t-P-h2-ω-ω5sin(ωst)
/ (Engineering 2, 2, E, iB) ...
...00) Angular velocity Ω2 and rotation angle θ at the time (t=T/2) when the horizontal deformation of the structure becomes maximum using the 00 formula.

seek. The deformed state at this time is completely different from that shown in FIG.

Ωt"Sosadaz=1+-1'h'ω/(1g44m)・
・・・・・・0[) θ＋S0Ωz −1+ −P−h ”・ω/(I2・E
, I, ω, 〉...02) Along with this angular velocity Ω2, Ylj[l! The moment M2 generated around the surface is expressed by equation 03).

M, = x, -ω・Ω2 ・・・・・・
G3) G3) Substituting equation (11) into 2, Mz “”(1+)”・ph”・ω”/(I2・E・
l1l) ......The horizontal deformation δ8 due to bending when moment M2 is applied to the top of the side structure is G4
) is expressed as G5) 2.

δs "Mt - h"/2・E'1B=(it)"
・P,h'・ω2/(2・I2・E2・(II)”)・
...05) Assuming that the horizontal deformation δ4 due to bending due to external force P is completely offset by the above δ, then δ, = δ
.

Therefore, from equation (1)2,05), P, h3/(3
・E・■m) = (II)”・ph′・ω2/(2・II・E2・(
1+)")...06) Here, considering that the weight W of the rotating body is distributed only around the outer circumference of radius r, the gravitational acceleration is G, and the weight of the frame is ignored, II
[If we abbreviate 2, we get 1+=wr”/G 12=wr”/4G, so by substituting this into equation 06) and converting it, we get a steel-frame tourist tower with a total weight of about 12,000 tons as a model structure. Assuming that, apply the following values to 07) 2.

E-2100t/cf, la =22m'G=9
80cm/5ec2. h=150mr=5m
, ω= 1257 rad/5ec200 )(
z Therefore, the required weight around the outer periphery of the rotating body should be about 0.065% of the total weight of the structure.

The piment M2 acting around the Y-axis of the rotating body acts on the structure as a vertical force (couple) and becomes a damping force, but as is clear from Fig. 4, The force N that makes up the couple does not always act on the structure in the vertical direction. If the vertical component is N, then N5=
It is expressed as Ncosθ, and the remaining component N5inθ becomes a horizontal force that causes twisting motion in the structure. Therefore, some consideration is required when the external force P is large, that is, when 02) θ becomes large.

For example, when P is 50 tons, 0'!
Assuming that it rotates by 5 rad, find N: N s = N-cos (0, 15 rad) = 0
．． 99 N Therefore, it has almost no effect on the required damping effect, and the remaining small amount of 0.0 IN becomes a horizontal component that causes twisting in the structure. If it is necessary to suppress this moment due to the nature of the structure, install stoppers for vertical positioning on both ends of the frame of the rotating body in the Y-axis direction to limit the rotation angle around the X-axis. Alternatively, two devices having half the performance of the vibration damping device described above may be installed in the structure, and the rotating bodies of each device may be rotated at high speed in opposite directions.

On the other hand, another calculation example for the case where an external force P due to an earthquake is applied is as follows.

When assuming the moment M2 applied to the top of the structure, if δ, = δA/2, then from the above equations (1) and G5), P-h3/
3・E・■,=8□・h2/2・E,I.

That is, since M, = P - h/3, using the above formula 03), M2 is 11 ・
It is expressed as ω・Ω=Ph/3...08).

The above-mentioned 1+=wr”/ obtained as a rough formula for It
Substituting G into equation 08) and converting, W=P-h=G/3・Ω2・(+) −r ” −−−
---(J9) is obtained.

Here, assuming that the external force P due to the earthquake is 100 Gaf, P
-0,1・W/C------ (2m).

Further, h is 500 m, r is 1.5 m considering making it as small as possible, and ω is 200 Hz.

In the calculation example for the wind mentioned above, the external force is relatively small, so the rotation angle (θ) around the X axis of the rotating body is assumed to be able to move freely in response to changes in the external force.The second is the relationship with the external force. However, in this example, the external force is large, and there is a possibility that some restrictions may be applied to θ.The second factor is considered independently of the external force, and is 1°01 (09 if z), G! From the Φ formula, w=o, 0038W.

That is, it is sufficient to use a rotating body having a weight of 0.4% of the weight of the structure.

FIG. 7 shows a case where the vibration of the middle- and low-rise structure 1 is controlled using a vibration damping bag xiO.

When an external force P such as an earthquake is applied to the medium-low-rise structure 1, horizontal deformation δ due to shearing occurs more prominently than bending deformation,
As a result of this shearing deformation, rotational deformation θ occurs in the beams 2 and columns 3, which are the horizontal and vertical members constituting the structure 1.
a)) causes a rotational deformation in the direction opposite to the rotational deformation θ of the beam, and a vibration damping device 10 installed on the side of the column 3 (FIG. 3(b)) causes a rotational deformation of the column 3 in the opposite direction. This is to cause rotational deformation in the direction.

8 to 10 show the vibration damping device IO installed on the upper surface of the beam 2 and its operating state. Vibration damping device 1
Since the configuration of 0 is the same as that described above, a description thereof will be omitted, and common members will be shown with the same reference numerals.

This vibration damping device 1O is connected to the beam 13.14 of the frame 15.
is rotatably supported in a horizontal state on support stands 11 and 12 in the X-axis direction fixed to the beam 2, and the rotating body 17 rotates at high speed in the direction of the arrow shown in the figure around a vertical rotation axis 16 in the X-axis direction. That's what I do.

If the angular velocity associated with the rotational deformation θ caused in the beam 2 by the external force P applied from the X-axis direction is the first, then the rotating body 17 of the vibration damping device 10 fixed to the beam 2 also has the same angular velocity. Ω is given.

Therefore, a moment Ml in the direction of the arrow shown in FIG. 9 is generated in a direction perpendicular to this angular velocity vector, that is, around the X-axis. The rotating body 17 generates rotational movement around the X-axis at an angular velocity Ω2 due to this moment M, so a moment Mz is generated in the direction perpendicular to this angle and the velocity vector, that is, around the Y-axis in the direction of the arrow shown in FIG. do.

This moment) M2 acts on the beam 2 via the support 1112 as a vertical force (couple) N, N, and rotational deformation of the beam 2 in the opposite direction to the rotational deformation θ1 due to shearing of the structure 1 occurs. Therefore, this cancels out θ6, eliminates the shear deformation of the structure 1, and suppresses vibration.

Figures 11 to 13 show the damping bag 210 installed on the side of the pillar 3 and its operating state, and parts common to Figures 8 to 1O are given the same reference numerals. This is an indication.

20 The vibration damping device 10 includes beams 13 and 14 of the frame 15.
is rotatably supported vertically on support stands 11 and 12 in the X-axis direction fixed to the pillar 3, and the rotating body 17 rotates at high speed in the direction of the arrow shown in the figure around a horizontal rotation axis 16 in the X-axis direction. That's what I do.

If the angular velocity associated with the rotational deformation θ caused in the column 3 by the external force P applied from the X-axis direction is Ω, then the rotating body 17 of the damping device 100 fixed to the column 3 also has the same angular velocity Ω.
, is given.

Therefore, a moment M in the direction of the arrow shown in FIG. 12 is generated in a direction perpendicular to this angular velocity vector, that is, around the X axis. The rotating body 17 has this moment M,
As a result, a rotational movement of angular velocity Ω2 is generated around the X-axis, and a moment (Mz) is generated in the direction perpendicular to this angular velocity vector, that is, around the Y-axis in the direction of the arrow shown in FIG.

This moment M2 acts on the column 3 as a horizontal force (couple) N, N via the support 1112, causing a rotational deformation in the opposite direction to the rotational deformation θ4 of the column 3 due to the shearing of the structure l. Therefore, this cancels out θ, eliminates the shear deformation of the structure, and suppresses vibration.

〔Example〕

FIG. 14 and FIG. 15 are installation examples of the vibration damping device having the above structure (main parts are given the same reference numerals).

The figure shows two vibration damping devices 10a on the roof floor of a high-rise structure 1.
, 10b are arranged.

On the roof floor of the structure 1, there are support stands 11a and 12a facing each other in the width direction (X-axis direction), and support stands 11a and 12a in the length direction (Y-axis direction).
and the support stands 11b facing each other.

12b, one vibration damping device 10a is rotatably supported on support stands 11a and 12a, and the other vibration damping device 1
0b is rotatably supported on the support stands 11b and 12b.

In this way, the two vibration damping devices 10a and 10b are connected to each other at 90°.
When arranged at a phase angle of 0', one vibration damping device 10a operates in response to an external force applied from the X-axis direction, and the other vibration damping device 10a operates in response to an external force applied from the Y-axis direction.
b is activated, and in response to an external force applied from any direction other than the X-axis and Y-axis directions, both of the damping devices are activated, so a damping effect in all directions can be obtained.

This vibration damping device 10 may be installed on an intermediate floor of the structure 1 if necessary.

FIGS. 16 and 17 show other installation examples of vibration damping devices, which are suitable for vibration control and structural design of high-rise structures having continuous walls as earthquake-resistant frames.

FIG. 16 shows an example in which a continuous wall 5 is provided in the center of the structure 1, and vibration damping devices 10 are installed in the uppermost layer and middle layer of the multi-layer wall 5. This is an example in which continuous walls 5 connected by boundary beams 6 are provided in the center of the structure 1, and a damping device 10 is installed on the top layer of each continuous wall 5.

When an external force such as an earthquake acts on a structure 1 having a continuous wall 5, bending deformation occurs in the continuous wall 5, but this bending deformation is bent back by the vibration damping device 10, so that the vibration of the structure 1 is controlled. can do.

Conventionally, in this type of structure, when an external force acts,
Excessive bending deformation occurs in the continuous walls, and the function as an earthquake-resistant structure deteriorates in the upper layer, resulting in a reverse shear phenomenon. (In the structure shown in Figure L7, the boundary beam deformation becomes large Therefore, as a solution, it is necessary to install and reinforce highly rigid hat beams and belt beams, and rational design of peripheral members such as vertical members of frame tubes and boundary beams, which are the outer peripheral members of multilayer walls, is required. Not only does this hinder the installation, but it also limits the use of the planar space on the installation floor.

However, in this invention, all the layers of the continuous wall from the lower layer to the upper layer function effectively as an earthquake-resistant frame, so there is no need to install hat beams or belt beams, and all of the above problems are solved. In addition, it becomes possible to design multi-layered walls around the outer periphery of high-rise structures.

FIGS. 18 and 19 are examples of installing vibration damping devices in medium- and low-rise structures.

Fig. 18 shows an example in which the damping device 10 is installed on the beam 2 on each floor of the structure 1, and Fig. 19 shows an example in which the damping device 10 is installed on the pillar 3 on each floor of the structure 1. It is something.

[Effects of the Invention] As explained above, according to the present invention, when an angular velocity around a specific axis is given to a rotating body rotating at high speed, a moment is generated around an axis perpendicular to this angular velocity vector. By combining the principles of Because it is configured so that the rotational deformation of the structure is detected by a sensor etc., and the rotational deformation of the structure is detected and the angular velocity corresponding to the detected amount is applied to the rotating body, there is no need to use any operation or control means. A damping effect can be obtained.

Furthermore, according to the present invention, by appropriately selecting the weight and rotational angular velocity of the rotating body, the required moment size can be set arbitrarily, and braking control over a wide period range is possible. Not only that, but the weight of the rotating body required to obtain the damping force is extremely light compared to the weight of the structure, so it is economically possible to achieve this effect at a low cost. There is.

Furthermore, this invention can provide an effective vibration damping effect when applied to both high-rise structures where bending deformation is predominant due to external forces, and medium- and low-rise structures where shear deformation is predominant due to external forces. , a vibration control method with a wide range of applications can be obtained regardless of the type of structure.

In addition, when this invention is applied to a high-rise structure having continuous walls, all the layers of the continuous walls work effectively as an earthquake-resistant frame, so there is no need to install reinforcing members, and the rational design of surrounding members becomes possible. At the same time, the use of flat space is no longer limited.

[Brief explanation of drawings]

Fig. 1 is a side view showing horizontal deformation and rotational deformation caused in a high-rise structure, Fig. 2 is a side view showing horizontal deformation caused by the method of this invention, and Fig. 3 is a side view showing the horizontal deformation caused by the method of this invention. A plan view showing the vibration damping device, Fig. 4 is a sectional view taken along the line I-1 in Fig. 3, Fig. 5 is a sectional view taken along the Figure 7(a)
, (b) is a side view showing shear deformation and rotational deformation of members occurring in a mid- to low-rise structure, Fig. 8 is a plan view showing a vibration damping device installed on a beam, and Fig. 9 is the I of Fig. 8. -1 line sectional view, 1st
Figure 0 is a sectional view taken along the line ■-■ in Figure 8, Figure 11 is a plan view showing the damping device installed on the pillar, and Figure 12 is I-1 in Figure 11.
The line sectional view, Figure 13 is the ■-■ line sectional view of Figure 11,
Figure 4 is a plan view showing an example of installing a vibration damping device in a high-rise structure, Figure 15 is a sectional view taken along line I[[-III in Figure 14, and Figures 16 and 17 are respectively Side view showing an example of installing a vibration damping device in a high-rise structure, No. 18
FIG. 19 and FIG. 19 are side views each showing an example of installing a vibration damping device in a medium- and low-rise structure. In the figure, 1 is the structure, 2 is the beam, 3 is the column, and 5 is the continuous wall 1.1
0 is a damping device, 16 is a rotating shaft, 17 is a rotating body, P is an external force applied to the top of a structure, δ is a horizontal deformation 1 caused to a structure by an external force, and θ is a horizontal deformation caused to a structure, beam, or column by an external force. The rotational deformation, δ, caused in is the horizontal deformation caused in the structure by the damping device. Figure A, J Japanese coins and more

Claims (5)

[Claims] (1) A rotating body installed inside the structure is rotated at high speed around a rotation axis that has a predetermined angle with respect to the direction of the external force, and the external force applied from the X-axis direction causes rotational deformation of the structure and the rotating body at an angular velocity of Ω_1. is generated, a moment M_1 is generated around the axis orthogonal to this angular velocity vector, and this moment M_1 is further used to generate angular velocity Ω_2 around the axis of the rotating body, so that the angular velocity vector is orthogonal to the Y axis. A method for controlling vibration of a structure, characterized in that a moment M_2 is generated, and the moment M_2 causes a rotational deformation of the structure in a direction opposite to the rotational deformation of the structure. (2) At least on the roof floor of a high-rise structure where bending deformation is predominant due to external forces, a rotating body is rotated at high speed around a vertical axis of rotation to cause rotational deformation in the opposite direction to the rotational deformation due to bending of the structure. A method for controlling vibration of a structure according to claim (1). (3) The vibration control method for a structure according to claim (2), wherein the rotating body is rotated at high speed in at least one of the uppermost layer and the intermediate layer of the multi-layered wall of the high-rise structure having the multi-layered wall. (4) On the beam of a mid- to low-rise structure where shear deformation is predominant due to external force, a rotating body is rotated at high speed around a vertical axis of rotation in a direction opposite to the rotational deformation that occurs in the beam due to shear of the structure. The vibration control method for a structure according to claim 1, which causes rotational deformation of the structure. (5) What is the rotational deformation that occurs in the column due to the shearing of the structure when a rotating body is rotated at high speed around a horizontal axis of rotation on the side of the column of a mid- to low-rise structure where shearing deformation is predominant due to external force? The vibration control method for a structure according to claim 1, wherein rotational deformation is caused in the opposite direction.