JP2529849B2 - Seismic bearing structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a seismic support structure, and more particularly to a structure in which an upper structure such as a bridge or a highway is supported on a pier, and the upper structure is When a slow movement occurs due to changes or changes over time, the movement is smooth and allows this movement without giving too much resistance, and in the case of a sudden vibration or shaking such as an earthquake, the upper part The present invention relates to a seismic support structure that effectively prevents the upper structure and the pier from falling or breaking by the same action as when the structure is fixed on the pier.

[Prior art]

Conventionally, in a structure such as a bridge, a plurality of bridge girders 2 having a predetermined length are placed on bridge piers 1 which are erected at predetermined intervals as shown in FIG.

Then, as a support structure of the bridge pier 1 and the bridge girder 2, the bridge girder 2
A movable bearing 3 and a fixed bearing 4 are provided in order to permit expansion and contraction or rocking due to changes in temperature, changes with time, and the like.

By the way, the conventional movable bearing 3 uses a roller bearing, a bearing plate bearing, a rubber bearing and the like, but these are used to restrain the load F in the horizontal direction of the bridge axis in order to cope with temperature changes, changes with time and the like. It is not structured to do. Therefore, when a vibration such as an earthquake occurs, the horizontal load F is entirely applied to the fixed bearing 4.

Therefore, the pier 1 and its foundation of the fixed bearing 4 are
Although it is necessary to make it rigid, there was a problem that the construction cost would be higher than when the horizontal load is evenly shared by all the piers 1.

In addition, it is actually happening that the bridge girder 2 comes off the movable support 3 and falls due to a past earthquake (Niigata earthquake, etc.).

[Object of the Invention]

The present invention was devised by focusing on such conventional problems, and the purpose thereof is to perform normal swinging and expanding / contracting of an upper structure in the same manner as a conventional movable bearing member. On the other hand, in the event of an earthquake, etc., it is possible to support lateral loads such as an earthquake, etc., in the same way as the fixed bearing members, and the pier and its foundation, etc., are the same regardless of whether they are fixed bearing parts or movable bearing parts. Lateral load can be shared, which prevents accidents that the upper structure falls off from the movable bearing member and can be prevented. At the same time, an economically advantageous structure can be constructed. It provides a structure.

[Structure of Invention]

In order to achieve the above object, the present invention supports a movable bearing member, a lower bearing member fixed to a fixed structure, and an upper bearing member attached to an upper structure so as to be swingable through an intermediate bearing member. And the intermediate support member is
An engagement chamber for movably supporting the upper bearing member is formed at a fitting connection portion between the upper bearing member and the lower bearing member, and a voltage whose fluidity changes when a voltage is applied inside the engagement chamber. A sensitive fluid is enclosed, electrodes for applying a voltage to the voltage-sensitive fluid are provided, and a power supply connection device for applying a voltage is connected to each of these electrodes, and when a vibration above a certain level is sensed in this power supply device, By connecting the vibration detection sensor that operates the power supply connection device, the normal vibration or expansion / contraction of the upper structure can be performed by following the movement of the movable support member, and at the same time, a certain magnitude of earthquake or the like will occur. When it occurs, the vibration detection sensor is activated to apply a voltage to the voltage-sensitive fluid enclosed in the cylinder via the power supply device, and the voltage-sensitive fluid is fixed by causing flow resistance. Seung equally as can support the lateral load of the earthquake and the member, it is an Abstract that will be shared equally lateral load regardless of the fixed portion and the movable portion was set to be.

Example of Invention

An embodiment of the present invention will be described below with reference to the accompanying drawings.

1 and 2 are cross-sectional views of a movable bearing part in an earthquake-resistant bearing structure in which the present invention is applied to a structure such as a bridge, and 11 is a fixed structure such as bridge piers erected at predetermined intervals. 1 is an upper structure such as a bridge girder having a predetermined length, and the upper structure 12 includes a fixed support member provided on a fixed structure 11 (not shown) and a movable support member provided on the fixed structure 11. It is supported by 13 and.

The movable bearing member 13 includes a lower bearing member 14 having a concave cross section fixed to a fixed structure 11 and an upper bearing member 15 fixed to an upper structure 12 and swingably supported via a pin 16. The member 17 and the member 17 are supported via an intermediate support member 18.

The intermediate bearing member 18 is a convex portion 17 of the upper bearing member 17.
In the fitting connection portion 19 between the a and the concave portion 14a of the lower support member 14, an engagement chamber 20 that movably supports via the sliding member 17b attached to the convex portion 17a of the upper support member 17 is formed. There is.

The engagement chamber 20 is hermetically sealed via a sealing material 20a (O-ring or the like), and the inside of the engagement chamber 20 is a convex portion of the upper bearing member 17.
Chambers 21a and 21b partitioned by 17a are formed.

The two chambers 21a and 21b are communicated with each other through a plurality of communication passages 22 formed in the sliding member 17b so that the voltage sensitive fluid 23 enclosed in the chambers 21a and 21b can flow. .

In addition, the voltage sensitive fluid 23 enclosed in the chambers 21a and 21b
The fluidity changes when a voltage is applied. The lower bearing member 14 and the upper bearing member 17 are provided with electrodes 24a and 24b for applying a voltage to the voltage-sensitive fluid 23, respectively.

The sliding member 17b is made of a material having a low coefficient of friction such as fluorine resin. In addition, the communication passage 22 provided in the sliding member 17b is formed by the divided chambers 21a, 2
If the voltage sensitive fluid 23 can be moved by increasing 1b, it is not always necessary to provide it.

A power supply connection device 25 (in this embodiment, a battery and a switch) that applies a voltage to the voltage-sensitive fluid 23 is connected to each of the electrodes 24a, 24b, and the power supply connection device 25 has a certain level or more. When the vibration of the
A seismic sensor 26 that operates 25 switches is connected.

The voltage-sensitive fluid 23 sealed in the engagement chamber 20 is, for example, an electrorheological fluid composed of a continuous phase such as silicone oil and a dispersed phase.
al fluid), the dispersed phase of this electrorheological fluid is substantially hydrophobic and is a conductor. Preferred are especially organic semiconductors such as phthalocyanine metal rust salts or polyacene-quinone.

As the properties of this electrorheological fluid, ≦
When an electric field of 3MV / m is applied, a static yield stress of ≧ 0.5K ・ Pa (S
tatic yield stress) can be generated, and ≤
It can pass a cd of ≤500 A / m ² with an electric field of 1 MV / m.

The present invention is configured as described above, and the expansion and contraction and the swinging action of the upper structure 12 when a normal temperature change or a small earthquake occurs can be performed by following the movement of the movable support member 13. If it is possible, and if a large earthquake such as a certain amount occurs,
This vibration is detected by the vibration detecting sensor 26, which sends a signal to the power supply connection device 25, and when the switch is turned on, a voltage is applied to the voltage sensitive fluid 23 enclosed in the engagement chamber 20. As a result, flow resistance (static yield stress) occurs instantaneously due to the property of the voltage-sensitive fluid 23, and the upper bearing member 17 is locked.

In this way, when the intermediate bearing member 18 of the movable bearing member 13 is fixed, it becomes the same as the fixed bearing member, and therefore supports the lateral load such as an earthquake. Therefore, the lateral load can be equally shared.

If such a structure is applied to the movable bearings of the bridge girders and piers of the bridge as in the above embodiment, there is no risk of the bridge girders falling off from the movable bearings in the event of an earthquake, etc., and safety can be improved. I can.

〔The invention's effect〕

According to the present invention, as described above, the movable bearing member is configured such that the lower bearing member fixed to the fixed structure and the upper bearing member attached to the upper structure are swingably supported via the intermediate bearing member. However, the intermediate bearing member forms an engagement chamber for movably supporting the upper bearing member at a fitting connection portion between the upper bearing member and the lower bearing member, and a voltage is applied to the inside of the engagement chamber. A voltage-sensitive fluid whose fluidity changes when applied is enclosed, electrodes for applying a voltage are provided to the voltage-sensitive fluid, and a power supply connection device for applying a voltage is connected to each of these electrodes, and a constant voltage is applied to this power supply device. When the above-mentioned vibration is detected, the vibration detection sensor that operates the power supply connection device is connected, so that the normal vibration and expansion of the upper structure can be performed by following the movement of the movable support member. , Above a certain level In the event of occurrence of such as a pressure-sensitive fluid, a flow resistance is created in the voltage-sensitive fluid so that the movable bearing member has a structure equivalent to that of a fixed bearing member, the lateral load such as an earthquake is evenly shared, and the upper structure comes off. It is possible to prevent it from falling down and breaking the fixed structure. Further, since all the fixed structures can evenly support the lateral load generated at the time of an earthquake, it is not necessary to construct a fixed structure having a particularly high strength, and therefore an economical structure such as a bridge can be constructed.

[Brief description of drawings]

FIG. 1 is a sectional view of a movable support member embodying the present invention,
FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is an explanatory view showing a conventional bridge support structure. 11 …… Fixed structure, 12 …… Upper structure, 13 …… Movable support member, 14 …… Lower support member, 17 …… Upper support member, 18 …… Intermediate support member, 19 …… Mating connection part, 20 ...... Engagement chamber, 23 ...... Voltage sensitive fluid, 24a, 24b ...... Electrodes, 25 ...... Power supply connection device, 26 ...... Vibration detection sensor.

Claims (1)

(57) [Claims] 1. A fixed bearing member provided on a fixed structure,
In an earthquake-resistant bearing structure in which an upper structure is supported by a movable bearing member provided in a fixed structure, the movable bearing member is attached to a lower bearing member fixed to the fixed structure and an upper structure. The upper bearing member and the upper bearing member are swingably supported via the intermediate bearing member, and the intermediate bearing member allows the upper bearing member to move to a fitting connection portion between the upper bearing member and the lower bearing member. An engaging chamber for supporting is formed, a voltage-sensitive fluid whose fluidity changes when a voltage is applied is enclosed inside the engagement chamber, and an electrode is provided for applying a voltage to the voltage-sensitive fluid. A seismic-resistant bearing structure, characterized in that a power supply connection device for applying a voltage is connected to the electrodes, and a vibration detection sensor for activating the power supply connection device is connected to the power supply device when a certain level of vibration is detected.