JP3455305B2 - Bridge girder vibration 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 a bridge girder, and more particularly to an additional vibration system type which makes it possible to amplify a control force by applying a reaction force to a bridge girder fulcrum such as an abutment or a pier. The present invention relates to a vibration damping device.

[0002]

2. Description of the Related Art As a conventional vibration control method for a structure,
Attach an additional vibration system tuned to the vibration cycle of the structure,
A method is widely used in which the vibration energy of a structure is converted into the vibration energy of the additional vibration system and the damping mechanism of the additional vibration system absorbs the vibration energy. This method is known to be particularly effective in the control of steady vibrations, and in the civil engineering and construction fields, vibrations of tower-like structures caused by wind are often used as control targets. On the other hand, this method is inferior in effectiveness to vibration due to strong unsteady earthquakes, and the control effect is remarkably deteriorated particularly in the case of receiving a ground motion of shock waveform.

As a method of controlling the vibration of a building structure due to an earthquake, a method using a pendulum and lever action has been proposed. In this method, a pedestal for taking this fulcrum is built separately from the structure, and the displacement difference of the response vibration between the structure and the pedestal is used to forcefully swing the pendulum that is not synchronized with the structure. . Then, the restoring force of the pendulum is amplified by the lever, and this is applied as a control force to the structure. Therefore, this method does not use the dynamic property of swinging of the pendulum, but merely statically uses the circumferential component force of gravity acting on the weight.

[0004]

In order to control the vibration of the bridge due to the earthquake, it is important from an engineering point of view to control the horizontal vibration of the bridge girder, and it is conceivable to attach a vibration control device to the bridge girder. However, the conventional method of attaching an additional vibration system does not provide sufficient damping effect during an earthquake.

Further, since the fulcrum required in the method utilizing the action of the pendulum and lever can be easily installed at the end of the abutment or pier, it is not necessary to install the pedestal. However, it is difficult to install a pendulum inside the bridge girder.

Therefore, the control force is generated by an additional vibration system, and the control force is not directly transmitted to the bridge girder but is transmitted through a lever having a fulcrum at the abutment or the top of the pier to amplify the control force. It can be transmitted to the bridge girder. The present invention aims to embody such a function.

[0007]

The present invention has been proposed in order to achieve the above object, and a lever is pivotally attached to an inside portion of a bridge girder fulcrum such as an abutment or a pier , and a weight and A vibration damping device composed of a damper and a spring for absorbing the vibration energy of the weight is movably provided, and the vibration damping device is locked to one end of the lever and
Contact communication with the other end of the bridge girder fulcrum portion of such before Symbol abutments and piers, earthquake
When the bridge girder vibrates due to motion, etc., the weight of the vibration control device
Vibration causes inertial force on the weight,
The reaction force from the bridge girder fulcrum adds to the inertial force to bridge the damping force.
A vibration damping device for a bridge girder configured to be able to act on a girder, and a wheel axle equipped with a plurality of gears is pivotally attached to a bridge girder inner side portion of a bridge girder fulcrum such as an abutment or a bridge pier, and a weight ,
Damper and bar for absorbing vibration energy of the weight
It provided with movably damping device consisting of Ne, the該制vibration apparatus through the wheel shaft, in contact with the bridge girder supporting point portion of such the abutment or pier, when the girder is vibrated by seismic motion or the like,
The weight of the vibration damping device vibrates to generate an inertial force in the weight,
The reaction force from the bridge girder fulcrum corresponding to the inertial force is the inertial force.
So that damping force can be applied to the bridge girder
The present invention provides a vibration damping device for a bridge girder having the above structure .

[0008]

When the bridge girder vibrates due to earthquake motion or the like, the weight of the vibration damping device vibrates accordingly, and an inertial force is generated in the weight. When this inertial force is transmitted from the frame to one end of the lever or one of the wheel shaft gears, the lever or the wheel shaft tries to rotate. A reaction force is generated from the bridge girder fulcrum of. Therefore, the reaction force of the bridge girder fulcrum is added to the inertial force of the weight, and a larger damping force can be applied to the bridge girder.

Further, the vibration energy of the bridge girder is converted into the vibration energy of the weight of the vibration damping device, and the vibration energy of the weight is absorbed by the damper of the vibration damping device. Thus, the vibration of the weight is damped in a short time, and the vibration of the bridge girder is also damped at an early stage. Furthermore, after the earthquake motion is stopped by the bar ne,該制vibration apparatus is returned to the neutral position.

[0010]

An embodiment of the present invention will be described in detail below with reference to the drawings. 1 and 2 show an embodiment of the invention described in claim 1, FIG. 1 is a mechanical model for explaining the mechanism of the vibration damping device 11 of a bridge girder, and FIG. 2 is a concrete structure of the vibration damping device 11. It is a model. The vibration damping device 11 is provided inside the bridge girder adjacent to the bridge girder fulcrum 12 such as an abutment or a pier. Reference numeral 13 is a base fixed to the inside of the bridge girder, and levers 14 and 14 are pivotally attached to the base 13 by pins 15 and 15.

Reference numeral 16 is a vibration damping device, and the vibration damping device 16 is a weight 1 which is movable in the bridge axis direction (arrow X direction).
7 and a spring 1 for supporting both ends of the weight 17 in the moving direction.
8, 18, 18 and 18, dampers 19 and 19 for absorbing the vibration energy of the weight 17, and the springs 18 and 1.
TMD (Tuned Mass Damper) consisting of 8, 18, 18 and frames 20, 20 that take the reaction force of the dampers 19, 19.
It is a configuration of shapes.

Arms 21 and 21 are provided on the upper surface of the weight 17.
Is locked at one end thereof, and the sliders 22, 22 are locked at the other ends of the respective arms 21, 21. The arms 21, 21
Are respectively pivotally attached to the frames 20, 20 by pins 21b, 21b, and elongated holes 21a, 21a, 21a in the direction perpendicular to the bridge axis (direction of arrow Y) are formed in the locking portions of the arms 21, 21. Therefore, the weight 17 and the slider 22,
22 do not interfere with each other in the direction perpendicular to the bridge axis (direction of arrow Y).

The arm 21 is rotatable about the pin 21b, and the length from the pin 21b to the engaging portion of the weight 17 is the length from the pin 21b to the engaging portion of the slider 22. Is greater than Sa. Therefore, as will be described later, when the bridge girder vibrates, the relative displacement between the slider 22 and the frame 20 becomes smaller than the relative displacement between the weight 17 and the frame 20, and the stroke of the spring 18 and the damper 19 can be suppressed small. .

Then, in the bridge axis direction of the frame 20 (arrow X
Direction)), the blocks 23, 23 are provided so as to project downward, and the inside of the blocks 23, 23, that is, the base 13
The block 13a is provided in the middle of the
Springs 24 and 24 are interposed between a and 23, respectively.

Here, rods 25, 25 are provided on the bridge girder fulcrum portion 12 side of the frames 20, 20 so as to project therefrom.
5, 25 are locked to one end of the levers 14, 14.
Further, rods 26, 26 are connected to the bridge girder fulcrum portion 12 such as the abutment or pier described above, and the rods 26, 26 are locked to the other ends of the levers 14, 14.

When the bridge girder vibrates due to an earthquake motion or the like, the base 13 also vibrates, and the vibration damping device 16 accordingly.
Since the weight 17 of oscillates in the bridge axis direction (arrow X direction),
An inertial force is generated in the weight 17. When this force is transmitted from the frame 20 and the rod 25 to one end of the lever 14, 14, a reaction force from the bridge girder fulcrum 12 is generated at the other end of the lever 14, 14 depending on its size. Therefore, the reaction force from the bridge girder fulcrum 12 is added to the inertial force of the weight 17 of the vibration damping device 16, and a larger damping force can be applied to the bridge girder via the pin 15.

Thus, the vibration energy of the bridge girder is converted into the vibration energy of the weight 17 of the vibration damping device 16,
The vibration energy of the weight 17 is absorbed by the damper 19 attached to the slider 22 of the vibration damping device 16. Thus, the vibration of the weight 17 is damped in a short time, and the vibration of the bridge girder is also damped at an early stage. Further, after the earthquake motion is stopped, the vibrations are suppressed by the springs 24, 24 interposed between the block 23 protruding from the frame 20 of the vibration damping device 16 and the block 13a protruding from the base 13. The device 16 returns to the neutral position.

In FIG. 1, reference numeral 27 denotes a damper component existing between the base 13 and the vibration damping device 16, which is so small that it can be ignored. Reference numerals 28 and 29 represent spring components and damper components possessed by the bridge itself including the foundation, bridge piers, bridge girders, and the like.

FIG. 3 shows an embodiment of the invention described in claim 2 and is a dynamic model of the vibration damping device 31 of the bridge girder. still,
For convenience of description, the same components as those of the vibration damping device 11 described above will be denoted by the same reference numerals, and description thereof will be omitted. The vibration damping device 31 is provided inside the bridge girder such as an abutment or pier adjacent to the bridge girder fulcrum 12, and the above-mentioned TMD type vibration damping device 16 is attached to the base 13 in the bridge axis direction (arrow X direction). And a wheel shaft 34 on which a plurality of gears 32 and 33 are mounted is pivotally mounted.

Further, rods 35, 35 are projectingly provided on the frame 20 of the vibration damping device 16, and racks 35a, 35a are engraved at the tips of the rods 35, 35 so as to mesh with the one gear 32, 32. Let Further, the rods 36, 36 are connected to the bridge girder fulcrum portion 12 such as the abutment or pier, and the racks 36a, 36a are engraved at the tips of the rods 36, 36 to mesh with the other gears 33, 33. . Incidentally, reference numeral 3
7 is a guide roller.

When the bridge girder vibrates due to an earthquake motion or the like, the base 13 also vibrates, and the vibration damping device 16 accordingly.
Since the weight 17 of oscillates in the bridge axis direction (arrow X direction),
An inertial force is generated in the weight 17. When this force is transmitted from the frame 20 and the rods 35, 35 to the one gear 32, 32, the other gear 33,
A reaction force from the bridge girder fulcrum 12 is generated at 33. Therefore, the reaction force from the bridge girder fulcrum 12 is added to the inertial force of the weight 17 of the vibration damping device 16, and a larger damping force can be applied to the bridge girder.

Thus, the vibration energy of the bridge girder is converted into the vibration energy of the weight 17 of the vibration damping device 16,
The vibration energy of the weight 17 is dissipated by the damper 19 attached to the slider 22 of the vibration damping device 16. Thus, the vibration of the weight 17 is damped in a short time, and the vibration of the bridge girder is also damped at an early stage. Further, after the earthquake motion is stopped, the vibration damping device 16 returns to the neutral position by the spring 24 interposed between the frame 20 of the vibration damping device 16 and the base 13.

In the invention of claim 1 and the invention of claim 2, only the control in the bridge axis direction has been described in the present embodiment, but the vibration damping device is constituted by the weight movable in the direction perpendicular to the bridge axis. If the vibration damping device is formed and connected to a bridge girder fulcrum such as an abutment or a bridge pier via a lever or a gear, control in the direction perpendicular to the bridge axis is also possible.

The present invention can be modified in various ways without departing from the spirit of the present invention, and it goes without saying that the present invention covers the modifications.

[0025]

As described in detail in the above embodiment, the present invention generates a control force against vibration by a vibration damping device including a weight, a spring, a damper and a frame. Then, the control force can be amplified and applied to the bridge girder by not transmitting the control force directly to the bridge girder but via a lever or wheel shaft gear connected to a bridge girder fulcrum portion such as an abutment or a bridge pier.

Further, since the structure is simple, the vibration damping device can be formed at low cost, which can contribute to the safety of the bridge at the time of an earthquake.

[Brief description of drawings]

FIG. 1 is a plan view of a dynamic model of a vibration damping device, showing an embodiment of the invention according to claim 1;

FIG. 2 is a partially cutaway perspective view of a concrete model of a vibration damping device.

FIG. 3 is a plan view of a dynamic model of the vibration damping device, showing an embodiment of the invention according to claim 2;

[Explanation of symbols]

11 Vibration damping device 12 Bridge girder fulcrums 13 base 14 lever 16 Vibration control device 17 Weight 18 spring 19 damper 20 frames 24 spring 25,26 rod 31 Vibration damping device 32, 33 gears 34 wheel axle 35,36 rod 35a, 36a racks

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hisatoshi Otsuka 1 Asahi, Tsukuba, Ibaraki Prefectural Civil Engineering Research Institute (72) Inventor Shigeki Unjo 1 Asahi, Tsukuba, Ibaraki Prefectural Civil Engineering Research In-house (72) Hideki Mukai, Asahi No. 1, Asahi, Tsukuba-shi, Ibaraki Civil Engineering Research Institute, Ministry of Construction (72) Intaker Takeyasu Suzuki, No. 1043 Shimoyama, Onigakiku, Tsukuba-shi, Ibaraki Kumagai-gumi Technical Research Institute (72) ) Inventor Takashi Kaneko 1043 Shimoyama, Onigakushi, Tsukuba-shi, Ibaraki, Kumagai Gumi Research Institute Ltd. (72) Inventor Minato Tanaka, 1043 Shimoyama, Onigakushi, Tsukuba, Ibaraki Prefecture, Kumagai Gumi Technical Research Institute, Ltd. (56) Reference JP-A-2-282584 (JP, A) JP 7-317834 (JP, A) JP 3-253676 (JP, A) JP 5-39607 (JP, A) Actual flat 2-60738 (JP, U) (JP, A) 58) Fields investigated (Int.Cl. ⁷ , DB name) E01D 1/00 E04H 9/02

Claims (2)

(57) [Claims] 1. A pivotally mounted lever on the bridge girder inside portion of the bridge girder supporting point portion of such abutments and piers, movement and weight, the damping device comprising a damper and a spring for absorbing vibration energy of the weight freely provided, and, a該制vibration apparatus while retaining one end of the lever in contact connecting the other end of the lever to the bridge girder supporting point portion of the front Symbol such as abutments and piers, bridge girder is vibration by earthquake motion or the like
When moving, the weight of the vibration damping device vibrates and becomes
A generative force is generated, and the reaction from the bridge girder fulcrum corresponding to the inertial force occurs.
Force acts on the inertial force to exert damping force on the bridge girder
A vibration damping device for a bridge girder characterized by being configured so that 2. A pivotally mounted a wheel shaft equipped with multiple gear girder inside portion of the bridge girder supporting point portion of such abutments and piers, from the weight, a damper and a spring for absorbing vibration energy of the weight with the composed damping device provided movably, the該制vibration apparatus through the wheel shaft, in contact with the bridge girder supporting point portion of such the abutment or pier, when the girder is vibrated by seismic motion or the like, the
The weight of the vibration damping device vibrates and an inertial force is generated in the weight,
The reaction force from the bridge girder fulcrum corresponding to the natural force is added to the inertial force.
Therefore, it is necessary to apply damping force to the bridge girder.
Vibration damping device for bridge girders, which is characterized by being made .