JP2542580Y2 - Damping device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device for suppressing vibration of buildings and towers caused by an earthquake or wind.

[0002]

2. Description of the Related Art FIG. 5 shows the principle of a tuned mass damper (hereinafter referred to as TMD) constituting the above-mentioned vibration damping device, wherein a spring p, a mass point m, and a damping mechanism q are mounted on the top of a structure A. When the natural period of the TMD is synchronized with the natural period of the structure and the structure vibrates due to an earthquake or wind, the vibration of the mass point of the TMD is excited, and the input energy to the structure is absorbed as the kinetic energy of the mass point of the TMD. , Dissipate this energy through the damping mechanism of the TMD.

It is to be noted that a pendulum or the like is used as a TMD spring for the purpose of supporting a mass point, and an oil damper is generally used as a damping mechanism. The mass point is about 1% of the amount of the structural material, and the attenuation rate of the TMD itself is typically about 0.15.

[0004]

[Problem to be solved by the invention] Natural period T of the pendulum
Is, if the suspension length is L and the gravitational acceleration is g

[0005]

(Equation 1)

However, when applied to a long-period structure, the suspension length L becomes very long, and the suspension cannot be incorporated into the structure. When the weight of a large structure increases, T
The mass point of the MD also needs to be increased proportionally, making the mechanism of the suspended structure difficult and uneconomical. Further, a damper is required as a damping mechanism, and a large stroke and a large capacity are required. Further, as the principle of TMD, the smaller the damping rate h of the damping mechanism, the more conveniently the energy of the structure is transmitted to the TMD. However, the larger h is better for the dissipation of energy. Oil dampers are not compatible
The effect of MD is limited.

Further, the movement of the TMD becomes excessive during a typhoon or a large earthquake.
D has stopped moving. Therefore, a separate stopper is required for this, and the mechanism becomes complicated and the cost increases. The present invention has been proposed in view of the above-mentioned problems of the prior art, and its purpose is to be applicable to long-period structures and large-sized structures.
An object of the present invention is to provide a vibration damper having a larger structure, a simple structure, and excellent economy.

[0008]

In order to achieve the above-mentioned object, a vibration damping device according to the present invention is provided with a concave sliding plate having a concave upper surface on a structure. , A variable sliding bearing having a pressurized fluid chamber mounted on the lower surface attached to the mass point, and connected to the pressurized fluid chamber, and a pressurizing valve and a depressurizing valve respectively interposed therein. And a depressurizing pipe connected to the accumulator and the pump, and a control device for adjusting the valves based on the measured data of the acceleration of the top of the structure and the mass point and the relative displacement of the same mass point and the building. .

[0009]

The vibration damping device according to the present invention is constructed as described above, so that when the structure vibrates, the mass also tends to slide on the concave sliding plate. Controlling the pressurizing valve and the depressurizing valve interposed in the pressurizing pipe and the depressurizing pipe through to pressurize the pressurized fluid chamber in the variable sliding bearing to a high pressure,
If most of the mass of the mass is subjected to liquid pressure, the frictional force can be made very small, so that the input energy to the structure can be effectively absorbed as the kinetic energy of the mass.

Once the mass begins to vibrate greatly, the controller reduces the pressure in the pressurized fluid chamber and adjusts the hysteresis in the variable slide bearing to be optimal,
It dissipates energy.

[0011]

FIG. 1 shows an embodiment of the vibration damping device according to the present invention, FIG. 2 shows the overall configuration of a variable sliding bearing of a mass in the vibration damping device, and FIG. 3 shows details of the variable sliding bearing. Indicates that
For the sake of simplicity, the upper surface of the concave slide plate is shown as a plane, but is actually formed as a concave curved surface.

Reference numeral 1 denotes a structure, on which a concave slide plate 2 having a concave upper surface is installed on the top of the structure 1, and a mass point 4 on which a variable slide bearing 3 is mounted is mounted on the concave slide plate 2. Is placed. The same mass 4 and the variable sliding bearing 3 are joined via a pin or a ball seat. The concave curved surface of the concave sliding plate 2 has a constant radius of curvature r, which is a kind of inverted pendulum, and the natural period of the inverted pendulum is

[0013]

(Equation 2)

The radius of curvature r is determined so that the natural period becomes the same as the natural period of the structure. The surface of the concave slide plate 2 is made of a stainless material 5 or the like. As is apparent from FIG. 3, the variable sliding bearing 3 is provided with a pressurized fluid chamber 6 on the lower surface at the center and a sliding material 7 such as fluororesin is fixed on the lower surface around the periphery. The seal member 9 is provided in the concave portion 8 provided in the above. The pressurized fluid chamber 6 further includes a pressurizing pipe 12 and a depressurizing pipe 13 in which a pressurizing valve 10 and a depressurizing valve 11 are interposed, respectively.
Are connected, and each of the pipes 12 and 13 is connected to the accumulator 1.
4 and the pump 15.

Further, as shown in FIG.
A displacement sensor 16 and an acceleration sensor 17 for measuring a relative displacement with respect to the object, an acceleration sensor 18 is attached to the mass point 4, and the acceleration of the top of the structure and the mass point 4 measured by the sensors 16, 17 and 18, and the mass point The amount of relative displacement between 4 and the structure 1 is sent to the controller 19, which processes these data and automatically operates the pressurizing valve 10 and the depressurizing valve 11,
The pressure of the pressurized fluid in the pressurized fluid chamber 6 is changed. The pressurization is not directly from the pump 15, but is performed by the accumulator 14.
The pump 15 is operated by a command from the controller 19 only when the accumulated pressure decreases,
Increase the accumulated pressure.

The sensors 16, 17, 18 and the controller 19 constitute a control device for the valves 10, 11. In the illustrated embodiment, since the structure 1 is configured as described above, when the structure 1 vibrates, the mass point 4 also tries to slide on the concave slide plate 2. The liquid in 6 is pressurized to high pressure so that most of the weight of mass 4 is received by fluid pressure. Therefore, since the frictional force can be made very small, the input energy to the structure 1 can be effectively absorbed as the kinetic energy of the mass point.

Once the mass 4 begins to vibrate significantly, the pressure in the pressurized fluid chamber is reduced to dissipate energy so that hysteresis damping in the variable slide bearing 3 is optimal. The optimum energy is determined as follows. As shown in FIG. 4, assuming that the mass point 4 having the weight W is oscillating with the amplitude D,

[0018]

(Equation 3)

[0019]

(Equation 4)

[0020]

(Equation 5)

[0021]

(Equation 6)

Assuming that the natural period of the structure is 8 seconds, r = 1
In the case of vibrating at 5.9 m and amplitude D = 1.0 m, to obtain a hysteresis damping rate of 15%, an apparent friction coefficient =
It becomes 0.015. Assuming that the sliding material is a fluororesin, Equation 6
From this, the force due to the liquid pressure = 0.85 W. That is, the pressure may be adjusted so that 85% of the weight of the mass point 4 is supported by the liquid pressure.

In practice, an optimal algorithm (algorithm) is calculated based on the vibration data of the structure 1 and the vibration of the mass 4.
hm), the input energy to the structure 1 is maximally dissipated by adjusting the pressure, that is, adjusting the frictional force.
Controller 19 to increase the damping effect as D
To control. In the case where the input becomes excessive and the mass 4 tries to move excessively, the pressure can be released to increase the frictional force, thereby providing a function of a brake.

In order to further enhance the vibration damping effect, an external force may be applied to the mass point 4 by an actuator to form a so-called powered passive system.

[0025]

According to the vibration damping device of the present invention, as described above, a kind of inverted pendulum in which the variable sliding bearing attached to the mass point is placed on the concave sliding surface on the structure is constituted. Therefore, unlike the conventional vibration damping device, the suspension length is not required,
It can be synchronized with long periods and can be used for long period structures. In addition, since the mass is supported by a sliding bearing,
Since the mechanism is simple and can handle large weights, it can be economically applied to large structures.

The variable slide bearing has a pressurized fluid chamber on the lower surface, and a pressurized pipe and a depressurized pipe provided with a pressurizing and depressurizing valve are connected to the chamber, respectively.
Each pipe is connected to an accumulator and a pump, and a control device for each valve is provided. By controlling the fluid pressure of the pressurized liquid chamber, the friction force of the variable sliding bearing, that is, the damping rate, can be freely adjusted. By changing, a larger vibration damping effect than the conventional TMD can be obtained. Further, since the variable sliding bearing has both the function of supporting the mass and the function of the damper, it is not necessary to separately provide a damper. Further, since it also has a braking function, a stopper is not required, and the configuration is simplified.

Further, since the liquid in the pressurized fluid chamber is pressurized by the accumulator, it can function even when there is no external power supply due to a power failure during an earthquake or the like.

[Brief description of the drawings]

FIG. 1 is a system diagram showing one embodiment of a vibration damping device according to the present invention.

FIG. 2 is a front view showing a variable-mass sliding bearing of a mass point in the vibration damping device.

FIG. 3 is a longitudinal sectional view showing details of the variable slide bearing.

FIG. 4 is a diagram showing a relationship between displacement of a mass point and a force.

FIG. 5 is an explanatory view schematically showing a conventional tuning mass damper.

[Explanation of symbols]

 Reference Signs List 1 structure 2 concave sliding plate 3 variable sliding bearing 4 mass 6 pressurized fluid chamber 10 pressurizing valve 11 depressurizing valve 12 pressurizing pipe 13 depressurizing pipe 14 accumulator 15 pump 16 displacement sensor 17 acceleration sensor 18 acceleration sensor 19 controller

Claims (1)

(57) [Scope of request for utility model registration] 1. A concave sliding plate having a concave upper surface formed on a structure, and a variable sliding bearing having a pressurized fluid chamber on a lower surface attached to a mass point is mounted on the sliding plate. A pressurizing pipe and a depressurizing pipe connected to the pressurized fluid chamber and provided with a pressurizing valve and a depressurizing valve are connected to an accumulator and a pump, respectively. And a control device for adjusting each of the valves based on measurement data of a relative displacement between the same mass point and the building.