JP2651508B2 - Vibration suppression device for structures - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an apparatus for suppressing vibration of a structure for suppressing vibration caused in the structure by an earthquake, wind, or the like.

[Conventional technology] Thin and tall structures such as skyscrapers and towers are liable to generate harmful vibrations due to disturbances such as strong winds and earthquakes. In addition, it is conceivable to apply a stress exceeding an allowable range to the frame of the structure.

In view of this, the present inventor has disclosed in Japanese Patent Application No. 60-241045 a tank provided at a predetermined position of a structure for storing a liquid that vibrates at the same cycle as the inherent vibration cycle of the structure. There has been proposed a vibration suppressing device that can suppress the vibration of the structure by the vibration of (1).

[Problems to be Solved by the Invention] However, in the above device, the vibration period of the liquid is long in response to a large vibration (for example, a strong wind with a wind speed of 50 m or more, or a vibration generated during a middle- or large-scale earthquake). When the value is set to, the depth of the liquid in the tank becomes very shallow. If the amplitude of the liquid becomes large in such a case, the liquid may be in a breaking state, and a great effect may not be obtained in attenuating the vibration.

In view of the above circumstances, the present invention has been made by developing the vibration suppression device proposed by the inventor of the present application, and is capable of effectively attenuating the vibration of a structure from a small amplitude to a large amplitude. It is intended to provide.

Means for Solving the Problems The present invention has been made to solve the above problems, and is provided at a predetermined position of a structure, and is connected to a horizontal portion and both ends of the horizontal portion. A tank capable of forming a □ -shaped tube by providing an upright portion, an orifice provided inside the horizontal portion, and inside the tank, a U-shape is stored between the upright portions. And a storage amount of the liquid is set such that the liquid vibrates in the tube at the same period as the inherent vibration period of the structure.

[Operation] According to the vibration suppressing device of the present invention, the vibrations of the liquid stored in the tube cause the vibrations caused by the earthquake or the wind in the building to be attenuated and suppressed. The vibration action in liquid is linear vibration in the length direction in each tube, and the free water surface, that is, both end faces in the tube are small, so even if the amplitude becomes large, the wave breaking phenomenon does not occur and the building Vibration is effectively suppressed.

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

Reference numeral 1 in the drawing indicates a vibration suppression device of the present embodiment,
The device 1, high-rise building in (structure) B, are installed on the roof of the floor surface B ₁ of the most effective is the relative vibrations caused by the wind.

As shown in FIG. 2, the vibration suppressing device 1 includes a tank 2
And the liquid W stored in the tank 2.

Tank 2 is intended to form an outer wall 2a and an inner wall 2b longitudinal section substantially □-shaped contour whose interior is hollow by a bottom-side horizontal portion 3 is grounded on the floor surface B _1, the bottom side horizontal Upright portions 4, 4 standing upright from both ends of portion 3, and both upright portions 4
And an upper horizontal portion 5 that connects the two, and these portions communicate with each other. Each horizontal part 3, 5 and both upright parts 4
Have the same cross-sectional area, and their length and depth are appropriately set.

As shown in FIG. 3, the inside of the tank 2 is divided into a plurality of parts by partitioning plates 6 provided at equal intervals in the depth direction. 7 are formed.

At the approximate center of the bottom horizontal portion 3 of each of the tubes 7, an orifice 8a for reducing the cross-sectional area of the tube 7 by a pair of movable plates 8 airtightly inserted into the tank 2 (tube 7). Each formed orifice
The size of 8a can be appropriately set according to the amount of insertion of the movable plate 8 into the tank 2.

The outer wall 2a forming the upper horizontal portion 5 of the tank 2 is provided with a vent 9 that opens the inside of each tube 7 to the outside and is covered by a lid 9a.

As the liquid W, water or the like is used, and in each tube 7 of the tank 2, the liquid W is formed in a U-shape so as to extend over the bottom horizontal portion 3 and the upright portions 4, that is, between the upright portions 4. Is stored. The tank 2 can also be used as a fire prevention water tank or the like.

The storage amount of the liquid W is set such that the length of the liquid W stored in the tube 7 is the same as the vibration period in the length direction of the liquid W and the vibration period inherent to the building B.

That is, the natural period T (sec) for a tube having a uniform cross section is (L: length of liquid part g: gravitational acceleration) Therefore, when the period T is 5 (sec), the liquid length is 12.4 m, and when it is 6 (sec), the liquid length is 17.9 m. Liquid W is stored in each tube 7 so as to have a length.

An inlet 10 for injecting the liquid W into each tube 7 and an outlet 11 for discharging the liquid W are provided on the outer wall 2a of the tank 2 so as to be openable and closable.

According to the vibration suppressing device 1 having the above configuration, the vibration cycle of the liquid W stored in each tube 7 in the tank 2 matches the vibration cycle inherent in the building B.
The vibration caused in the building B by the earthquake or the wind is attenuated and suppressed by the vibration of the liquid W. The vibration action in the liquid W is a linear vibration in the length direction in each tube 7, and since the free water surface, that is, both end faces in the tube 7 are small, even if the amplitude becomes large, the wave breaking phenomenon does not occur. The vibration of the building B is effectively suppressed. Therefore, if the length of the tube 7 and the storage amount of the liquid W are appropriately set, the vibration can be suppressed from a small amplitude to a large amplitude.

In addition, the inherent vibration period of the building B is based on a change in floor load,
It fluctuates (increases) due to the magnitude of the amplitude, the experience of the large amplitude due to an earthquake, or the like. The adjustment operation can be easily performed.

It is important that the vibration suppression device that contacts the building be sufficiently safe even in the event of a large earthquake or a storm that exceeds the design wind speed of the device. The device 1 is safe because the liquid W is stored in the tank 2, but the liquid W inside is also safe because the upper part of the □ -shaped tank 2 is in communication. It is designed so that excessive pressure is not applied to the tank 2 even when the tank 2 vibrates greatly. Further, as a final safety device, if the pair of movable plates 8 are brought into contact with each other to close the orifice 8a, the vibration of the liquid W can be stopped, and an excessive force may be applied to the building B. Can be prevented.

Further, the degree of the attenuation of the vibration of the liquid W can be adjusted by adjusting the opening degree of the orifice 8a and the orifice effect. In addition, the damping adjustment of the liquid W can use the resistance of the damping net or the like in addition to the opening degree of the orifice 8a, and also needs to take into account the viscosity of the liquid W and the elements of the flow resistance in the tube 7.

In the above embodiment, although installed a vibration suppressing device 1 on the floor B ₁ in the roof of the building B, if a large vibration suppressing device 1 of dimensions, as shown in FIG. 4, a building B
May be arranged over a plurality of floors.

Further, in the vibration suppression device indicated by reference numeral 20 in FIG. 5, the cross-sectional area of the bottom horizontal portion 3 in the tank 2 is set to be larger than that of the upright portions 4. In this case, the storage amount of the liquid W in the tube 7, that is, the length is different from the case where the respective sectional areas are equal as in the above-described embodiment, but also corresponds to the inherent vibration period of the building B. Is determined.

Furthermore, the vibration suppression device 1 of the above embodiment corresponds to one horizontal direction, that is, the length direction of the tank 2 (the tube 7), but by arranging the two tanks 2 orthogonally to each other. , Can respond to vibrations in two horizontal directions.

[Effects of the Invention] As described above, according to the apparatus for suppressing vibration of a structure of the present invention, the apparatus is installed at a predetermined position of the structure, communicates with the horizontal part, and stands upright at both ends thereof. A tank capable of forming a □ -shaped tube by providing an upright portion, an orifice provided inside the horizontal portion, and a liquid stored in the tank in a U-shape between the upright portions. The liquid has a storage amount set so as to vibrate in the same cycle as the inherent vibration cycle of the structure in the tube, and the vibration action in the liquid is Because of the linear vibration in the length direction in the tube and the small free water surface, even when the amplitude becomes large, the wave breaking phenomenon does not occur, and the vibration of the structure from small to large amplitude can be effectively used. Restrain You.

In addition, by simply adjusting the amount of liquid stored in the tube, it is possible to easily correspond to the inherent vibration period of the structure.

Further, by adjusting the opening degree of the orifice, it is possible to easily adjust the damping degree of the vibration of the liquid, and it is also possible to stop the vibration of the liquid for safety in the event of a large earthquake or the like.

[Brief description of the drawings]

1 to 3 are views showing an embodiment of the present invention. FIG. 1 is a schematic view showing a state where the apparatus is installed on the roof of a building, FIG. 2 is a longitudinal sectional view, and FIG. Is a perspective view with a part cut away, FIG. 4 is a view showing a state where it is installed at another place (a place over a plurality of floors), and FIG. 5 is a longitudinal sectional view of another embodiment. DESCRIPTION OF SYMBOLS 1 ... Vibration suppression device, 2 ... Tank, 3 ... Bottom side horizontal part, 4 ... Upright part, 7 ... Tube, 8a ... Orifice, B ... Building (structure).

Claims (1)

(57) [Claims] 1. A tank which can be formed at a predetermined position of a structure and has a horizontal portion and upright portions communicating with the horizontal portion and standing upright at both ends thereof, thereby forming a square tube. An orifice provided inside the horizontal portion, and a liquid stored in a U-shape between the upright portions inside the tank, wherein the liquid has a unique structure of the structure in the tube. A vibration suppression device for a structure, wherein the storage amount is set so as to vibrate at the same period as the vibration period.