JPH0157205B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration control device for reducing low frequency vibrations of structures such as road bridges and railway bridges.

For convenience, the explanation will be given below using a traffic bridge as an example.

Generally, a traffic bridge has a structure in which a bridge 1 is supported at both ends by piers 2, as shown in FIG. In this type of traffic road bridge, as the number of vehicles running on the bridge increases and the traveling speed increases, excessive external force is applied to the road bridge. Coupled with the decrease in bending rigidity, extremely large vibrations are induced in the road bridge. Such vibrations may be caused by bridge vibrations depending on the situation.
The atmosphere generates air pressure vibrations, which become low-frequency sound pressure waves, usually below 30 hertz, that propagate to the surrounding environment, which can manifest as so-called low-frequency pollution.
Furthermore, buildings that are close to each other due to vibration propagation in the ground,
Vibration can also cause vibration pollution, as it can cause houses to loosen, causing shutters, glass doors, etc. to rattle, or the vibrations in the house itself can cause great discomfort to residents.

This is the mechanism by which noise and vibration pollution occurs. Conventionally, countermeasures for the vibration of traffic bridges include improving and changing the vibration properties of traffic bridges, such as increasing the rigidity by reinforcing bridges and piers, or adding auxiliary piers to increase the number of support points on the bridge. In order to insulate the low-frequency sound pressure itself that propagates into the atmosphere, they installed soundproof walls, covers, etc. in an effort to reduce the discomfort caused to residents.

However, the reality is that such conventional measures have not achieved sufficient vibration and noise reduction effects, and the use of land space is also required when installing auxiliary piers on existing traffic bridges, reinforcing bridges, etc. At the same time, they were often subject to physical constraints and had drawbacks such as construction problems.

The present invention is fundamentally different from the conventional vibration reduction measures as described above, and by actively applying vibration control force to the structure according to its vibration properties, the present invention reduces the vibration of the structure. The present invention relates to a vibration control device that reduces vibration and improves its vibration properties.

FIG. 2 shows a conceptual diagram of the control force block in the present invention. 3 is a traffic road bridge vibration system to be targeted for vibration reduction, 4 is a vibration detector, 5 is a control circuit, and 6 is a drive device that generates control force.

FIG. 3 shows the driving equipment 6 of the vibration control system for traffic bridges applying the above-mentioned control force block concept. In the figure, 1 is a bridge, 2 is a pier, 10 is an arm attached to the bridge 1, 12 is a hydraulic exciter main body, and 11 is a connecting rod.

With this configuration, the physical quantities (displacement, velocity,
The acceleration is measured by the detector 4, and this detection signal is sent to the control circuit 5. A control force corresponding to this vibration is generated from the drive device 6 via the control circuit 5, and the control force is applied to the connecting rod 11 and the arm 10. Traffic road via bridge 3
is applied to achieve vibration reduction of the traffic road bridge 1.

By using the push and pull force of the hydraulic vibrator body 12 to expand and contract the span l between the tips of the two connecting rods attached to it, a moment is applied to the bridge 1 and the control force required for the vibration control described above is obtained. It is something. Further, the push/pull force can be adjusted by changing the voltage applied to the controller (not shown) of the hydraulic vibrator, and can be easily incorporated into the system shown in FIG. 2.

In the above embodiment, the arms are attached to both ends of the traffic bridge and the other ends of the arms are connected to each other by a hydraulic vibrator/connecting rod, but the vibration control device using the hydraulic vibrator of the present invention It can also be applied to towers, building antennas, floors, and other structures by devising a mounting method.

As described above, according to the present invention, a hydraulic vibrator is used to generate a control force along the longitudinal direction of the connecting rod.
Hydraulic exciters use hydraulic pressure of up to 100 atmospheres, so 1
It can generate a push and pull force of 100Kgf per cm ² ,
Compared to other drive devices, it has the advantage of being smaller and providing greater control force, as well as being able to apply a suppressing moment to the structure, which has the effect of reducing vibration.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a general traffic bridge, Fig. 2 is a block diagram showing a control system of the present invention, and Fig. 3 is an embodiment of the installation of a hydraulic vibrator to a traffic bridge according to the present invention. FIG. In the figure, 1... Bridge, 2... Pier, 3...
Bridge vibration system, 4...Detector, 5...Control circuit, 6
... Drive equipment, 10 ... Arm, 11 ... Connecting rod, 12 ... Hydraulic exciter main body. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A vibration control device for a target structure that generates vibrations in response to an external force, including a pair of arms connected to the target structure at a predetermined interval, and a connecting rod having a longitudinal direction with one end connected to each of the arms. , a detector for detecting the vibration, and a hydraulic vibrator installed between the other ends of the connecting rods and generating a control force along the longitudinal direction of the connecting rod based on the detection result of the detector. vibration control device.