JPH0220247Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a low frequency pollution prevention device for a bridge.

When cars pass over a bridge, the vibrations of the bridge girder can cause low-frequency pollution. Various methods have been proposed to eliminate this low frequency pollution, but
In either case, the structure is complex or cannot be fundamentally solved, so they are not appropriate.

Therefore, the present invention provides a low-frequency pollution prevention device for bridges that solves these problems.The feature of this invention is that a tank is installed at a suitable location on the bridge girder or along its entire length, and the upper part of the tank is In addition to providing an air layer, a plurality of liquid layers are provided above and below the bridge so that they do not mix with each other and form an interface below the air layer. According to this configuration, it is difficult for a vehicle to pass over the bridge. The bridge girder vibrates due to
The resulting low frequency waves cause the multiple layers of liquid in the tank to vibrate and wave, creating waves at the interfaces between the liquids, the interfaces between each liquid and the inner peripheral surface of the tank, and the top layer of liquid and the air layer. Energy due to low frequencies is consumed at the interface between the two, and the generation of low frequencies is eventually suppressed, making it possible to eliminate low frequency pollution.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3. 1 is a bridge pier, and 2 is a bridge girder extending between the piers 1. In this embodiment, a tank 3 is installed inside the bridge girder 2 over the entire length thereof. Appropriate amounts of a first liquid (for example, water) 4 and a second liquid (for example, oil) 5 are placed in this tank 3. Note that both liquids 4 and 5 are used that do not mix with each other. Reference numeral 6 indicates supply pipes for the first and second liquids 4 and 5. Note that a weir 7 is appropriately provided in the tank 3 so that the first and second liquids 4 and 5 are evenly distributed in the tank 3.

In the above configuration, when the vehicle 8 passes over the bridge girder 2, the bridge girder 2 vibrates, and the low frequency generated thereby causes the first and second liquids 4, 5 in the tank 3 to vibrate.
is wavy, and the interface between the first and second liquids 4 and 5, the interface between the first and second liquids 4 and 5 and the inner peripheral surface of the tank 3, and the interface between the upper surface of the second liquid 5 and air. Energy due to low frequencies is wasted at the interface between the two.

A second embodiment of the present invention will be described based on FIG. In this embodiment, a third liquid (for example, water) 9 is placed on top of a first liquid (for example, water) 4 and a second liquid (for example, oil) 5, and the first and second liquids 4, 5
Rubber partition membranes 10, 11 are provided between the second and third liquids 5, 9 to prevent the liquids 4, 5, 5, 9 from mixing with each other. Also, two supply pipes 6 are provided.

According to this configuration, the interface between the first liquid 4 and the partition membrane 10, the interface between the second liquid 5 and the partition membranes 10 and 11, the interface between the third liquid 9 and the partition membrane 11, Energy due to the low frequency is consumed at the interface between the first to third liquids 4, 5, 9 and the inner circumferential surface of the tank 3, and at the interface between the upper surface of the third liquid 9 and air.

As described above, according to the present invention, when a car passes over the bridge, the bridge girder vibrates, and the resulting low frequency causes the multiple layers of liquid in the tank to vibrate and wave. Energy due to low frequencies is consumed at the interfaces between the liquids, the interfaces between each liquid and the inner peripheral surface of the tank, and the interfaces between the uppermost liquid and the air layer, and eventually the generation of low frequencies is suppressed. It can eliminate low frequency pollution.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a side view, FIG. 2 is a cross-sectional view, and FIG. 3 is a cross-sectional view of the main part. FIG. 4 is a cross-sectional view of essential parts showing another embodiment of the present invention. 1... Pier, 2... Bridge girder, 3... Tank, 4... First liquid, 5... Second liquid, 6... Supply pipe, 7... Weir,
8...Automobile, 9...Third liquid, 10, 11...Partition membrane.

Claims (1)

[Scope of utility model registration request] A tank is installed at a suitable location on a bridge girder or along its entire length, an air layer is provided at the top of the tank, and multiple liquid layers are provided at upper and lower positions below this air layer to form an interface without mixing with each other. A low-frequency pollution prevention device for bridges featuring: