JPH01312173A - Vibration controller for structure - Google Patents

Abstract

PURPOSE:To control vibration of structures by a method in which a partition part to divide a liquid in a tank is detachably set in the liquid so that it vibrates with a given phase difference from that of the intrinsic vibration of a structure in the same period as the intrinsic vibrating period of the structure. CONSTITUTION:The level of drinking water 5 in a tank 4 is detected by a water level sensor 15 and sent out to a controller. When the wire 12 of a winch 14 is sent out on the basis of signals of the sensor 15 by the controller, a cover 8 is lowered and a partition part 9 goes into the water 5. The part 9 is then immersed to a depth at which the vibrating period of the water 5 in the room 10 divided by the part 9 is equalized with the intrinsic vibration period of the structure 2. When external forces such as wind or earthquake acts on the structure 2, the water 5 vibrates with a given phase difference in the same period as the intrinsic vibrating period of the structure 2, whereby damping the vibration of the structure 2.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to a vibration suppression device for a structure that suppresses vibrations caused in the structure by earthquakes, wind, etc. This invention relates to a vibration suppression device for structures that has multiple functions.

"Conventional technology and its issues" In recent years, architectural and civil engineering structures have become larger, more diverse in form, In addition to being lightweight, it has a structure that is highly flexible against external forces. Lightweight and flexible structures like this tend to have low natural frequencies and low internal vibration damping, so they are susceptible to various unpredictable vibrations due to external forces such as earthquakes and wind. There is a possibility that it will occur.

In particular, as mentioned above, as the size of structures increases, the amplitude of vibrations excited by external forces also increases.This vibration gives unnecessary anxiety to people living inside the structure, and also causes damage to the structure. The stress within the allowable range (=j
There was a fear of giving in.

Therefore, in the specification of Japanese Patent Application No. 60-241045, the inventor of the present application proposes to vibrate at a predetermined position of a structure with the same period as the natural vibration period of this structure and with a required phase difference. A vibration suppression device has been proposed in which a tank for storing a liquid is provided and the vibration of the structure can be suppressed by the vibration of the liquid, thereby solving the above-mentioned problem.

By the way, it is believed that such vibration suppression devices are most effective when installed in buildings, etc. A water storage tank for storing water, etc. is usually installed, so it goes without saying that a device that combines a vibration suppression device and a water storage tank would be highly desirable from the standpoint of space saving.

This invention was made by developing the vibration suppression device previously proposed by the inventor of the present application in view of the circumstances of the TIEJ article, and also functions as a water storage tank! f.

``Means for Solving the Problems-1 Therefore, the present invention provides a method for installing a tank at a predetermined position of a structure, storing a liquid inside the tank, and supplying a liquid to the structure. A partition member that partitions the liquid is applied to the liquid via a lifting device so that it vibrates at the same vibration period as the natural vibration period and with a required phase difference from the natural vibration of these structures. The above-mentioned problem is solved by configuring a vibration suppressing device for a structure that can be freely accessed and removed.

[Example 1] Hereinafter, an example of the present invention will be described with reference to the drawings.

Figures 1 to 3 are diagrams showing a vibration suppressing device which is a first embodiment of the present invention. In the figure, reference numeral 1 is a vibration suppressing device, and this vibration suppressing device 1 is a vibration suppressing device that is caused by wind. It is installed in high-rise buildings (structures), which are said to be most effective against vibrations.

This vibration suppressing device I consists of a support base 3 consisting of a laminated 11η convex structure made of an elastic body such as rubber and a steel plate, a tank 4 placed on the support base 3, and a beverage stored in the tank 4. It is roughly composed of water 5.

The tuck 4 is a rectangular cylindrical water storage tank for storing drinking water 5 of the building 2, and has an open structure at one end. Further, reference numeral 6 is a water supply pipe connected to the upper part of the tank 4, and reference numeral 7 is a water outlet pipe connected to the lower part of the tank 4.

Further, on three sides of the tank 4, a lid body 8 having a shape that covers an opening at the upper end of the tank 4 is disposed. A partition member 9 having a square lattice shape in plan view is provided on the lower surface of the lid 8 in a projecting manner and is sized to fit into the tank 4 . The interval between each grid of this partition member 9 is set to a, as shown in FIG. The upper 1 in 4 (respectively square chambers 10 and 10 in plan view with an inner diameter of 1)
It is divided into .

The lid body 8 is installed on one side of the tank 4-1 and is connected to the saw pulley 1.
The persimmons are hung from three sides by a wire 12 via the wire 1, and the wire 12 is further connected via a pulley 13 to a winch (elevating device) 14 installed on the roof of the building 2.

Therefore, the lid 8 can be freely moved in and out of the tank 4 (drinking water 5 therein) by feeding and winding the winch I4 and twister I2. Also, code 15
is a water level detection sensor disposed on the 5- surface inside the tank 4. Note that this vibration suppressing device 1 is provided with a control device (not shown). This control device includes the water level detection sensor 15, I5,
are connected, and the control device has a function of controlling feeding and winding of the wire I2 of the winch I4 based on detection signals from these sensors.

The tank 4 and the partition member 9 are preferably made of a material that does not corrode even after long-term use (for example, plastic). However, these tanks 4
The material of the partition member 9 may be appropriately determined depending on construction conditions and the like, and is not limited to the above-mentioned materials.

Next, the operation of the vibration suppressing device 1 having the following configuration will be explained.

The water level detection sensor 15 detects the current level of the tank 4.
The water level of the drinking water 1'-1 water 5 inside is detected and sent to the control device. ]17j The control device is a water level detection sensor 1
The winch I4 is commanded to operate based on the signal No. 5, and the wires 6-12 are paid out based on the winch I4. As a result, the lid 8 is gradually lowered, and the partition member 9 protruding from its lower surface is immersed into the water 5 inside the tuck 4 from its lower end. While detecting the water level of the drinking water 5 with the water level detection sensor 15, the switch 14 is commanded to stop operating with the lower end of the partition member 9 recessed to a depth of ■1, and the switch 14 (" The feeding of the wire 12 is stopped based on this.

The partition member 9 is recessed to a depth of 1. ((j: , the chambers 10, 10 divided by this partition member 9, - The depth is such that the vibration period of the drinking water 5 inside is the same as the natural vibration period of the building 2. When the partition member 9 is immersed into the drinking water 5 by a predetermined depth t, and a part of the drinking water 5-1 is separated, external forces such as wind and earthquakes are applied to the building 2 in 11. When activated, the drinking water 5 separated by the partition member 9 vibrates at the same period as the natural vibration period of the building 2 and with a required phase difference, thereby reducing the vibration of the building 2. effectively attenuated.

Then, the drinking water 5 in the tuck 4 is discharged from the water outlet pipe 7 as needed in the building 2, or the drinking water 5 is supplied into the tank 4 from the water supply pipe 6 at a fixed rate.
When the water level of the drinking water 5 in the tank 4 fluctuates, the water level detection sensor I5 detects this fluctuation, and based on this detection signal, the control device sets the immersion depth of the partition +A9 to a constant value I. Command the switch I4 to operate. Due to the dirt, a constant vibration suppression effect can be obtained even if the water level fluctuates.

In addition, the total weight of the drinking water 5 in the room 10, l01- divided by the partition member is /15θ~// of the mass of the building 2.
/θθ is preferable.

In other words, if it is less than ///θθ, sufficient vibration damping effect will not be obtained for the building 2, and if it is less than //Fθ, the mass of drinking water 5 or the structural design of the building 2 will be affected. This is because the impact on the building will be greater, and it will be necessary to re-design the structure of the building.

Next, a method for determining the inter-lattice distance 2 and the immersion depth TI of the partition member 9 will be described below.

The vibration system including the building 2 and the vibration suppression device 1 includes a fourth
It can be approximated and simplified to the vibration model shown in the figure. This vibration model has a spring constant K. Through the spring 21A and Tatsuno and Bot 23Δ of damping rate 1+o, the quality f
tM. Vibration system A (vibration model of building 2) in which object 22A is supported by M, @ quantity M,
This is a model in which a vibration system B (vibration model of drinking water 5 in room IO) supported by an object 22B is connected in series.

In such a vibration model, when vibration system A starts to vibrate due to an external force such as an earthquake or wind applied to the object 22A, vibration system B starts to vibrate with a phase delay of //4 cycles, so these vibration systems By matching the vibration periods of A and B, vibrations to the vibration system can be suppressed.

Here, since the mass of the object 22B is approximately 2% of that of the object 22A, the natural vibration period 'ro of the building 2 is determined by the quality hIM determined from the viewpoint of structural design and the spring constant { It is determined almost uniquely by .Therefore,
The vibration period of the vibration suppression device 1, i.e. each chamber 10
The vibration period T1 of the drinking water 5 inside is the natural vibration period T of the building 2. The dimensions, capacity and weight of this chamber 10 and the storage amount of drinking water 5 may be set so as to match the above. The behavior of the drinking water 5 stored in the room IO (j) can be analyzed as follows.

The relationship between the third-order natural vibration period TJ of sloshing and the third-order natural circular frequency ω is expressed by the following equation.

TJ=2π/ω, (1) In the above equation (1), I-1 is the storage depth of drinking water 5, 9
If ω is the gravitational acceleration, then ω is a quantity expressed by the following equation.

(IIJ=/T■1tanh(ka) [(2) Furthermore, if the width of the chamber 10 is shifted from λ, then 1 in the above equation (2) can be obtained from the following equation.

, +=(2,i] )π/a
(3) Therefore, the natural vibration period T of sloshing can be found from equations (+) to (3) shown below. In particular, in order to suppress the vibration described above, it is sufficient to use a natural vibration period of 1'' for the first-order sloshing.

This is expressed by the following formula.

As explained above, the vibration suppressing device 1 of this embodiment can suppress vibrations excited in the building 2 by external forces such as earthquakes and wind. In particular, in the vibration suppressing device I of this embodiment, the partition member 9 is set to be freely accessible to and from the drinking water 5 (), and the partition member 9 is controlled by the control device.
Since the depth of immersion into the drinking water 5 is controlled to be a constant value H, a constant vibration suppression effect is always obtained even if the water level of the drinking water 5 in the tank 4 fluctuates. be able to. In addition, the drinking water 5 whose vibration is suppressed for the building 2 is the drinking water 5 in the rooms 10, 10, . Therefore, the drinking water 5 located at the bottom of the tank 4 is not affected in any way. Therefore, according to this embodiment, it is possible to realize a vibration suppressing device I that also has the function of a water storage tank.

"Modified Embodiments of the Invention" The structure vibration suppressing device (J) of this invention is not limited to the details of the above embodiments, and various modifications are possible.Hereinafter, with reference to the drawings, modifications of this invention An example will be explained.

FIG. 5 is a diagram showing a vibration suppressing device for a structure, which is a second embodiment of the present invention. In the following description, the same reference numerals are used for the same components as in the first embodiment (=tL, and the description thereof will be omitted.

In this embodiment, the partition members 9 protruding from the lower surface of the lid 8 of the vibration suppressing device 1 are constituted by cylindrical members arranged in a row in a plane, as shown in FIG.

Therefore, in this embodiment, as in the first embodiment, vibrations of the building 2 are transmitted through the rooms 10 and 10 separated by the partition member 9.
, , and are effectively damped by the drinking water 5 in them, and an effective vibration suppressing effect can be obtained. The shape and number of the tanks 4 and the partition members 9 are arbitrary, and may be appropriately determined in consideration of the shape of the building 2, vibration properties, etc.

Similarly, in Moeki's first and second embodiments, the control device constantly controls the immersion depth I-T of the partition member 9 in accordance with the water level of the drinking water 5 in the tank 4. Earth”-
Needless to say, a vibration sensor may be installed in the drinking water 5, and the partition member 9 may be controlled to be submerged into the drinking water 5 only when a large vibration is caused by the vibration sensor.

``Effects of the Invention'' As explained in detail below, according to the present invention, a tank is provided at a predetermined position of a structure, a liquid is stored inside the tank, and the The liquid is moved through a lifting device through a partitioning member that separates the liquid so that it vibrates at the same vibration period as the natural vibration period of the structure and with a required phase difference from the natural vibration of these structures. Since the vibration suppressing device is constructed such that it can be freely moved in and out of the structure, it is possible to obtain a constant vibration suppressing effect even if the liquid level in the tank fluctuates. Therefore, according to the present invention, it is possible to realize a vibration suppressing device for a structure that also has the function of a water storage tank.

[Brief explanation of the drawing]

1 to 3 are diagrams showing a vibration suppressing device for a structure according to a first embodiment of the present invention, in which FIG. 1 is a plan view;
Figure 2 is a sectional view taken along the line ■-■' in Figure 1, Figure 3 is a schematic diagram showing the state in which it is installed in a building, Figure 4
The figure is a schematic view showing a vibration model of a structure and a vibration suppressing device, and FIG. 5 is a plan view showing a vibration suppressing device for a structure according to a second embodiment of the present invention. 1. Vibration suppression device, 2. Building (structure), 4.
Tank, 5... Drinking water (liquid), 9... Partition part A, 14... Winch (4 lowering device). Figure 4

Claims (1)

[Claims] A tank is provided at a predetermined position of the structure, and
A liquid is stored inside this tank, and the liquid is stored in this tank with a vibration period that is the same as the natural vibration period of the structure, and with a required phase difference from the natural vibration of these structures. A vibration suppressing device for a structure, characterized in that a partition member that partitions the liquid so as to vibrate is provided so as to be able to enter and exit the liquid via an elevating device.