JPH09195226A - Base isolation bridge falling preventing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To base-isolate a bridge beam to prevent the falling of a bridge, and prevent the bridge beam and a bridge pier or a bridge base from being ruptured or broken. SOLUTION: Base isolation bridge falling preventing devices 10 are set on both sides of a steel beam S, and each device is roughly formed of a base plate 1 fixed to the end part of a web W; a base isolation rubber 12 mounted on the base plate 1 in such a manner as to be slightly slidable in the bridge axial direction; a support plate 16 on which the base isolation rubber 12 is mounted; and a bracket 14 fixed to the support plate 16 and also fixed to a bridge pier P.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation fall bridge prevention device and seismic isolation fall bridge prevention device which can prevent a bridge girder from being seismically isolated and prevent a bridge from being destroyed, and can also prevent the bridge girder and piers or abutments from being destroyed. Belong to.

[0002]

2. Description of the Related Art Hitherto, a bridge prevention device has been used to prevent a bridge from being dropped. In particular, it has been desired to install two or more bridge prevention devices in response to the Great Hanshin Earthquake.

Various types of falling bridge prevention devices have been developed and provided. The main ones are stopper-type bridge prevention devices and connected-type bridge prevention devices.

The stopper-type collapse prevention device is roughly constructed by a stopper piece fixed to a bridge girder and a locking piece fixed to a bridge abutment or a bridge pier for locking the stopper piece.

In the conventional connection type bridge prevention device, a plate-shaped steel material is fixed between bridge girders to prevent a bridge from falling.

Further, in recent years, there has been provided a connection type bridge prevention device having a shock absorbing device. Such a connection type collapse prevention device is a shock absorber provided on each bridge girder or abutment,
A PC steel material (connecting material) for connecting these shock absorbing devices is provided, and the bridge girders are connected to each other to reduce the impact force generated in the PC steel material, thereby preventing the bridge from falling. A coil spring, a thick plate-shaped elastic sponge, or the like is mainly used as the shock absorber. Even if the girder ends fall off the pier, the PC girder prevents the bridge girder from falling to the ground.

[0007]

By the way, there are various modes of bridge collapse due to an earthquake. One of them is to prevent bearings and bridge collapse when a large acceleration amplitude and displacement are input to the bridge girder from the pier or abutment due to the earthquake. Some are caused by the destruction of equipment, etc., and the ends of bridge girders coming off the piers or abutments.

In such a case, in the stopper-type bridge prevention device, the locking piece collides with the stopper piece, and a shocking force is generated on the locking piece and the stopper piece, and further on the bridge girder and the bridge pier or abutment. Becomes

The connection type bridge prevention device operates only when there is a phase difference between the bridge girders and when the ends of the bridge girders come off the piers or abutments. Therefore, in the connection type bridge prevention device, an impact force is generated on another bridge prevention device, for example, the stopper type bridge prevention device and further the bridge girder and the pier or abutment. Even in the connection type bridge prevention device equipped with a shock absorber, the shock absorber is to reduce the shock force of the connecting material and to isolate (shock) the shocking force input to the bridge girder due to an earthquake or the like. is not.

Therefore, the seismic isolation of the bridge girder is desired from the viewpoint of reducing the acceleration amplitude and displacement from the bridge pier or abutment, preventing the other bridge collapse prevention devices, and the damage and destruction of the bridge girder and the bridge pier or abutment, and preventing the bridge collapse. It is rare.

The present invention has been made in view of such demands, and an object of the present invention is to prevent the bridge girder from being seismically isolated and prevent the bridge from falling, and also to damage or destroy the bridge girder and the pier or abutment. The point is to provide a seismic isolation fall bridge prevention device that can prevent such damage.

[0012]

SUMMARY OF THE INVENTION The gist of the present invention is a seismic isolation falling bridge prevention device which is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling and to isolate the bridge girder. Fixed to the base plate, seismic isolation rubber fixed to the base plate-fixed to the pier or abutment,
A seismic isolation bridge preventive device comprising: a bracket to which the seismic isolation rubber is fixed. The gist of the invention according to claim 2 is a seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and which is isolated from the bridge girder and fixed to the end of the bridge girder. A base plate provided with a shear hole on a surface opposite to the surface on the bridge girder side in a state of being attached, and a seismic isolation rubber attached to the base plate, the shear hole being provided on the surface on the bridge girder side,
A seismic isolation comprising: a shear hole of the seismic isolation rubber, a shearing piece that can be fitted into the shearing hole of the base plate, and a bracket fixed to a pier or abutment and to which the seismic isolation rubber is fixed. It exists in the bridge prevention device. The gist of the invention according to claim 3 is a base isolation plate which is fixed to a bridge girder and a bridge pier or abutment to prevent a fall bridge, and which is a seismic isolation falling bridge prevention device for isolating the bridge girder, the base plate being fixed to the end of the bridge girder. A seismic isolation rubber fixed to the base plate and having a shear hole on a surface opposite to the surface on the bridge girder side in a fixed state; and a seismic isolation rubber fixed on a pier or abutment. A seismic isolation bridge comprising: a bracket having a shear hole provided on a surface of the bridge girder side; a shear hole of the bracket; and a shearing piece insertable into the shearing hole of the seismic isolation rubber. It exists in the prevention device. The gist of the invention according to claim 4 is a seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and which is isolated from the bridge girder and fixed to the end of the bridge girder. A base plate provided with a shear hole on a surface opposite to the surface on the bridge girder side in a state of being attached, and attached to the base plate;
Seismic isolation rubber provided with shear holes on both sides, and fixed to the pier or abutment, the seismic isolation rubber is attached
A bracket provided with a shear hole on the surface of the bridge girder, a shear hole of the seismic isolation rubber, a shear piece insertable into the shear hole of the base plate, and a shear hole of the bracket,
A seismic isolation bridge preventive device comprising a shearing hole that can be fitted into the shearing hole of the seismic isolation rubber. The gist of the invention according to claim 5 is a seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and is a base plate fixed to the end of a bridge girder. A seismic isolation rubber fixed to the base plate, a support plate fixed to the seismic isolation rubber, and a bracket fixed to a bridge pier or abutment, the support plate being fixed, The seismic isolation bridge preventive device is characterized in that a guide portion is provided at a lower portion of the base plate, the guide portion extending in a bridge axis direction of the bridge girder and guiding the lower portion of the support plate. The gist of the invention according to claim 6 is a seismic isolation falling bridge prevention device that is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and that is seismically isolated from the bridge girder. A base plate provided with a shear hole on a surface opposite to the surface on the bridge girder side in a state of being attached, and a seismic isolation rubber attached to the base plate, the shear hole being provided on the surface on the bridge girder side,
A shearing piece that can be inserted into the shearing hole of the seismic isolation rubber and the shearing hole of the base plate, a support plate that is fixed to the seismic isolation rubber, and a bracket that is fixed to a pier or abutment and to which the support plate is fixed. And a guide portion that extends in the bridge axis direction of the bridge girder and that guides the lower portion of the support plate is provided in the lower portion of the base plate in the installed state. It exists in the device. The gist of the invention according to claim 7 is a seismic isolation fall bridge prevention device that is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and is a base plate fixed to the end of the bridge girder. And a seismic isolation rubber provided with a shear hole on the surface opposite to the surface on the bridge girder side in a fixed state, and the surface on the bridge girder side to which the seismic isolation rubber is attached. A support plate having a shear hole formed therein, a shear hole insertable into the shear hole of the support plate and the shear hole of the seismic isolation rubber, and a bracket fixed to the pier or abutment and fixed to the support plate And a guide portion that extends in the bridge axis direction of the bridge girder and that guides the lower portion of the support plate is provided in the lower portion of the base plate in the installed state. Dress It resides in. The gist of the invention according to claim 8 is a seismic isolation falling bridge prevention device which is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling, and which is to be isolated from the bridge girder. Base plate having a shear hole on a surface opposite to the bridge girder side in a repaired state, a seismic isolation rubber attached to the base plate and having shear holes on both sides, and the seismic isolation rubber Shear hole, a shearing piece that can be fitted into the shearing hole of the base plate, the seismic isolation rubber is attached, a support plate provided with a shearing hole on the surface of the bridge girder side, and fixed to a pier or abutment, A bracket to which the support plate is fixed, a shear hole of the support plate, and a shearing piece that can be fitted into the shearing hole of the base isolation rubber are provided. Extending the bridge axis direction of the bridge girder consists in seismic isolation girder prevention device, wherein a guide portion bottom is guided in the support plate is provided. The gist of the invention according to claim 9 is that the shear hole has a length in the bridge axis direction longer than a length of the shear piece in the bridge axis direction of the bridge girder, and the shear piece is inside the shear hole. It exists in the seismic isolation fall bridge prevention apparatus in any one of Claims 1 thru | or 8 which can slide in a bridge axial direction.

The seismic isolation rubber according to the present invention reduces the acceleration amplitude and displacement input to the bridge girder from the pier or abutment due to an earthquake or the like, and prevents damage to the bearings and other bridge prevention devices and thus the bridge girder and the pier or abutment. Prevent and prevent falling bridges.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) As shown in FIG. 1, a seismic isolation bridge preventive apparatus 10 according to Embodiment 1 is fixed to an end portion of a steel girder S and a pier P. In FIG. 1, only one steel girder S is drawn. In addition, the bearings and other fall prevention devices and floor slabs are omitted. Further, although FIG. 1 depicts a statically determined state, the steel girder S is in a stretched state due to temperature.

The seismic isolation bridge preventive device 10 is installed on both sides of the steel girder S, and has base plates 11 fixed to the end portions of the web W, and the base plate 11 respectively.
To the bridge pier P, the seismic isolation rubber 12 attached to the bridge so as to be slightly slidable in the bridge axis direction, the support plate 16 to which the seismic isolation rubber 12 is attached, and the support plate 16 and the bridge pier P. And the bracket 14 that is formed.

As shown in FIGS. 2 and 3, the base plate 11 has a substantially L-shaped vertical cross section, and a guide portion 11 is provided at a lower portion thereof.
It is a steel member (SS400 etc.) in which a was formed. The guide portion 11a extends in the bridge axis direction of the steel girder S shown in FIG.
The lower end portion is bent upward so that the lower portion of the support plate 16 described later is guided in the bridge axis direction. Steel girder S
A shear hole 11b is provided on the surface opposite to the side surface. The shear hole 11b is formed in the center of the base plate 11 in a side view of mounting. The shape is a rectangular parallelepiped that is long in the bridge axis direction. The depth is about 60% of the plate thickness of the base plate 11. The base plate 11 is fixed to the web W shown in FIG. 1 by bolts. Bolt holes 11c for fixing are formed at four corners.

As shown in FIGS. 4 to 6, the seismic isolation rubber 12 has a generally thick plate-like shape as a whole. As shown in FIG. 6, a shear rubber 12a is sandwiched between steel plates 12b at the center in the thickness direction. The shear rubber 12a is a rectangular plate-shaped body. The steel plate 12b has a square cross section and is attached to the shear rubber 12a by vulcanization molding. A shear hole 12c is formed in the center of the steel plate 12b. This shear hole 12
c has the same size as the shear hole 11b of the base plate 11. The outer surface of the base isolation rubber 12 is covered with rubber to form a rubber layer 12d as shown in FIG. Further, one surface of each steel material (the surface on which the base plate 11 slides and the surface on which the support plate 16 shown in FIG. 1 slides) is coated with Teflon (polytetrafluoroethylene) (not shown). The thickness and material of the shear rubber 12a may be determined in consideration of the horizontal force applied by the seismic force.

As shown in FIG. 14, such seismic isolation rubber 12 is used.
Shear hole 12c of the base plate 11 and the shear hole 11b of the base plate 11
The base plate side shearing piece 13 is slidably fitted in the bridge axial direction. Base plate side shearing piece 13
Is a steel member having a rectangular parallelepiped outer contour as shown in FIG. The height is the same as that of the shear hole 12c shown in FIGS. The width (length in the bridge axis direction) is about half of the length in the bridge axis direction of the shear hole 12c.

The bracket 14 is fixed to the pier P facing the side surface of the end portion of the web W as shown in FIG. As shown in FIGS. 9 and 10, the mounting plate 14a facing the web W shown in FIG. 1, the stiffening plate 14b vertically provided on the back surface of the mounting plate 14a, the upper plate 14c, and the lower plate 14d. It consists of and. Each component is a steel material (SS400 etc.). The stiffening plate 14b, the upper plate 14c, and the lower plate 14d are welded to the mounting plate 14a. Bolt hole 1 in lower plate 14d
4e is opened, and the anchor bolt 15 is inserted into this bolt hole 14e and fixed to the pier P shown in FIG.
The support plate 16 is fixed to the bracket 14.

The support plate 16 is a steel plate-like member having a shear hole 16a formed in the surface on the steel girder S side in the mounted state as shown in FIGS. The shear hole 16a has the same size as the shear hole 12c provided in the seismic isolation rubber 12 shown in FIGS. 4 to 6. In order to stiffen the support plate 16, a vertical plate 16b and a horizontal plate 16c are welded to the back surface (the surface opposite to the surface provided with the shear holes 16a).

A bracket side shearing piece 17 is formed in the shearing hole 16a of the support plate 16 and the shearing hole 12c of the seismic isolation rubber 12.
Is slidably fitted in the bridge axis direction. The bracket side shearing piece 17 shown in FIGS. 13 and 14 is the same as the base plate side shearing piece 13 shown in FIG.

In order to install the seismic isolated bridge preventive device 10 as described above, first, as shown in FIG.
1 is fixed to the web W of the steel girder S. Next, the base plate side shearing piece 13, the vibration isolating rubber 12, the bracket side shearing piece 17, and the bracket 14 are sequentially mounted slidably in the bridge axis direction, and the bracket 14 is fixed to the pier P (not shown in FIG. 13). When fixed as described above, the state shown in FIG. 14 is obtained. In other words, the seismic isolation rubber 12 is sandwiched between the web W and the bracket 14 via the base plate 11 and the support plate 16.
In addition, at the factory, each component is assembled, temporarily fixed,
It is also possible to carry it into the field, lift it up, and fix it to the steel girder S and pier P while installing it temporarily. In such a case, it is possible to reduce the installation labor at the site and shorten the installation time.

The operation of such seismic isolation bridge preventive device 10 is shown in FIG.
This will be described with reference to FIGS. 15 to 18 are plan sectional views. In order to facilitate understanding of the relative displacement between the steel girder S and the bridge pier P (not shown), the position of the steel girder S is fixed and the bridge pier P is drawn in the leftward direction of the drawing.
15 to 18, only the seismic isolation bridge preventive device 10 installed on one side of the steel girder S is shown. Further, only a horizontal section is shown for easy visual recognition.

When the pier P vibrates from the stationary state shown in FIG. 15 (when a relative displacement occurs between the pier P and the steel girder S),
As shown in FIG. 16, the shearing piece 13 on the base plate side is
Shear holes 11b in the base plate 11 and the vibration isolating rubber 12,
It contacts the end face of 12c.

Further, when the relative displacement between the steel girder S (bridge girder) and the bridge pier P becomes large, the vibration isolating rubber moves in the moving direction of the steel girder S as shown in FIG.
Reference numeral 7 designates a vibration isolation rubber and shear holes 12c, 1 in the support plate 16.
It contacts the end face of 6a. Isolation rubber 1 at this point
2 does not deform. Depending on the relationship between the frictional force between the base plate 11 and the seismic isolation rubber 12 and the frictional force between the seismic isolation rubber 12 and the support plate 16, the shearing piece 13 on the base plate side and the shearing piece 17 on the bracket side may move. Can occur at the same time. Further, the bracket-side shearing piece 17 may be moved first.

Further, when the relative displacement between the steel girder S and the bridge pier P becomes large, as shown in FIG. 18, the shear holes 11b and 12 are formed.
When the base plate side shearing piece 13 or the bracket side shearing piece 17 is brought into contact with the end faces of c and 16a, the vibration isolating rubber is deformed.

The relative movement between the steel girder S and the bridge pier P is smoothly controlled by being restricted in the bridge axial direction by the guide portion 11a of the base plate 11 shown in FIGS. 1, 2 and 3.

Although FIGS. 15 to 18 show the case where the pier P moves to the left of the paper, the same operation is shown when the pier P moves to the right of the paper.

The seismic isolation falling bridge prevention device 10 according to the first embodiment
Is configured as described above, and has the following effects.

The acceleration amplitude and displacement input from the bridge pier P to the steel girder S due to an earthquake or the like is reduced to prevent damage and destruction of the bearings and other bridge prevention devices (not shown) and by extension the bridge girder and pier P or abutment. It is possible to prevent falling bridges.

Further, since the seismic isolation rubber 12 can be expanded and contracted in the direction perpendicular to the bridge axis, vibration of the bridge girder in the direction perpendicular to the bridge axis can also be isolated.

As a result, the seismic isolation falling bridge prevention apparatus 10 according to the first embodiment can improve the vibration resistance of the bridge.

Further, the structure can be simplified and simplified as compared with the connection type bridge prevention device using the shock absorber. As a result, it is possible to reduce the manufacturing cost of the bridge prevention device.

Further, the installation of the seismic isolation bridge preventive device 10 on the bridge pier P is easier than the installation work of the connection type bridge preventive device or the stopper type bridge preventive device because there is little processing for the bridge pier P and the steel girder S. Can be done. As a result, the installation work time and the construction period can be shortened and the construction cost can be reduced.

Further, it is possible to prevent the traveling vehicle on the steel girder S from slipping, falling, and colliding during an earthquake, as well as falling of a pedestrian and dropping from a bridge.

Further, it is possible to prevent damage to the balustrade, lighting equipment and other incidental equipment.

The steel girder S expands and contracts depending on the temperature, but the expansion and contraction is caused by the shear holes 11b and 12 which are longer than the shearing piece in the bridge axis direction.
It is absorbed by c and 16a, so that the deformation of the seismic isolation rubber 12 does not have to be stressed. In other words, the shear deformation of the seismic isolation rubber 12 due to the temperature shrinkage of the steel girder S can be prevented.
As a result, it is possible to maintain a stable seismic isolation force against the horizontal force caused by the earthquake.

The shear holes 11b, 12c and 16a can absorb microscopic movements due to vibration such as live load, yawing due to wind, rolling, pitching and the like. As a result, the fatigue of the seismic isolation rubber 12 can be prevented.

Further, since it is covered with Teflon, the seismic isolation rubber 12 can be slid easily. As a result, the above effect can be guaranteed, and the steel material of the seismic isolation rubber 12, the base plate 11 and the support plate 1 can be obtained.
Wear of 6 can be reduced.

Further, since the vertical plate and the horizontal plate of the support plate 16 can make a space (larger) between the steel girder S and the bracket 14, when the steel girder S vibrates in the direction perpendicular to the bridge axis. Also for steel girder S lower flange F
The bracket 14 (shown in FIG. 14) does not hit the bracket 14.

The length of the shearing holes 11b, 12c, 16a in the bridge axis direction may be made equal to the width of the shearing piece 13 on the base plate side or the bracket side shearing piece 17 (length in the bridge axis direction).

Also, the base plate 11 and the seismic isolation rubber 12
Only between or with the seismic isolation rubber 12 and the support plate 16
A shearing piece may be provided only between and.

Also, the base plate 11 and the seismic isolation rubber 12
Alternatively, the seismic isolation rubber 12 and the support plate 16 may be fixed to each other. The fixing method can also be fixed by a method suitable for carrying out the present invention, such as welding, fusion bonding, and bolt fastening. In such a case, the manufacturing cost can be reduced and the installation work time can be shortened as compared with the first embodiment.

Further, the above structure is further simplified, the base plate 11 fixed to the steel girder S without the support plate 16, the seismic isolation rubber 12 fixed to the base plate 11, the seismic isolation rubber 12 and the pier. It is also possible to configure only the bracket 14 fixed to P.

Further, the seismic isolation bridge preventive device 20 shown in FIG.
By extending the vertical lengths of the base plate 21 and the support plate 26 as described above, vibration in the vertical direction can also be isolated. In such a case, the vibration resistance of the bridge can be further improved. In the figure, reference numeral 22 is seismic isolation rubber, reference numeral 2
Reference numeral 3 is a base plate side shearing piece, reference numeral 24 is a bracket, and reference numeral 27 is a bracket side shearing piece.

(Embodiment 2) A seismic isolation bridge preventive apparatus according to Embodiment 2 is a steel girder S as shown in FIGS.
And the abutment A (not shown in FIG. 21). In FIG. 20, the bearing is conceptually drawn.

The seismic isolation bridge preventive device 40 includes a base plate 41 fixed to the end of the web W of the steel girder S, a seismic isolation rubber 42 fixed on the base plate 41, and a bracket 44 fixed to the parapet L. And a shearing piece 43 interposed between the base plate 41 and the bracket 44.

The base plate 41 is a steel plate-like member having a rectangular shape that is long in the vertical direction when viewed from the mounting plane, and is fixed to the steel girder S by bolts B.

The seismic isolation rubber 42 has a rectangular parallelepiped outer shape as shown in FIG. 22, and has steel plates 42a, 42b on both sides (the surface opposite to the surface fixed to the base plate 41).
Has been fixed. The steel plate 42a has a shear hole 42d having a rectangular parallelepiped inner contour formed at the center of the mounting side view. Laminated steel plates (not shown) in rubber are laminated inside at intervals in the direction perpendicular to the bridge axis.

As shown in FIG. 20, the bracket 44 has a front rear circular shape in a side view of mounting, and a mounting portion 44a extending at a right angle is formed in a square portion. This mounting piece 4
Anchor bolt 45 is inserted into anchor hole 44c (shown in FIG. 23) opened in 4a and fixed to parapet L. In the figure, reference numeral 46 is a seat plate. A shear hole 44b is also formed in the center of the mounting side view as shown in FIG. The shear hole 44b is the shear hole 4 of the seismic isolation rubber 42.
It has a shape equal to 2d.

A shearing piece 43 is fitted in the two shearing holes 42d and 44b. The shearing piece 43 is a rectangular parallelepiped made of steel as shown in FIG. 24, and has a thickness such that the seismic isolation rubber 42 and the bracket 44 are in contact with each other as shown in FIG.

Since the seismic isolation bridge preventive device 40 is constructed as described above, it is possible to prevent the steel girder S from falling from the abutment A.

Also in the second embodiment, each shear hole may be a hole elongated in the bridge axis direction. In such a case, as in the seismic isolation bridge preventive device according to the first embodiment,
It is possible to absorb temperature shrinkage, microtremor, etc. in the long shear hole in the bridge axis direction.

Further, in the above embodiment, the steel girder S
However, the present invention is not limited to this, for example, a PC
It can also be applied to digits.

In the present invention, laminated rubber may be used as the seismic isolation rubber. In such a case, the number of laminated steel plates inserted into the laminated rubber can be made suitable for carrying out the present invention. Further, as the laminated rubber, for example, one containing a lead core (so-called LRB or the like) can be used. In such a case, the damping effect can be enhanced by the plastic deformation.

Further, the positions, shapes, etc. of the above-mentioned constituent members such as the base plate, the seismic isolation rubber are not limited to those in the above-mentioned embodiment, and the positions, shapes, etc. suitable for carrying out the present invention can be adopted. For example, the shape of the seismic isolation rubber may be a columnar shape or the like suitable for carrying out the present invention.

Also in the second embodiment, the shearing piece can be made movable in the bridge axis direction as in the first embodiment.

In the above figure, the same components are designated by the same reference numerals.

[0060]

Since the present invention is configured as described above, the following effects can be obtained. The seismic isolation rubber reduces the acceleration amplitude and displacement input from the pier or abutment to the bridge girder due to an earthquake, etc., and prevents damage and destruction of the bearings and other bridge prevention devices, and thus the bridge girder and pier or abutment, and prevents the bridge from falling. be able to. As a result, the bridge girder can be seismically isolated to prevent the bridge from falling, and the bridge girder and the pier or abutment can be prevented from being damaged or destroyed. As a result, according to the present invention, the earthquake resistance of the bridge against an earthquake can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a seismic isolation falling bridge prevention device according to a first embodiment of the present invention.

FIG. 2 is a mounting side view of the base plate according to the first embodiment.

FIG. 3 is a mounting front view of the base plate according to the first embodiment.

FIG. 4 is a perspective view of the seismic isolation rubber according to the first embodiment.

FIG. 5 is a plan view of the seismic isolation rubber according to the first embodiment.

FIG. 6 is a sectional view taken along line AA of FIG. 5;

FIG. 7 is a partially enlarged view of FIG. 6;

FIG. 8 is a perspective view of a base plate side shearing piece according to the first embodiment.

FIG. 9 is a mounting side view of the support plate according to the first embodiment.

FIG. 10 is a front view of mounting the support plate according to the first embodiment.

FIG. 11 is a mounting side view of the bracket according to the first embodiment.

FIG. 12 is a mounting front view of the bracket according to the first embodiment.

FIG. 13 is an assembly conceptual diagram of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 14 is a mounting front sectional view of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 15 is a plan cross-sectional view showing the operation of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 16 is a plan sectional view showing an operation of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 17 is a plan cross-sectional view showing the operation of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 18 is a plan cross-sectional view showing the operation of the seismic isolation bridge preventive device according to the first embodiment.

FIG. 19 is a mounting front sectional view of a seismic isolation bridge preventive device according to another embodiment.

FIG. 20 is a mounting side view of the seismic isolation bridge preventive device according to the second embodiment.

FIG. 21 is a mounting front view of the seismic isolation bridge preventive device according to the second embodiment.

FIG. 22 is a perspective view of a seismic isolation rubber according to the second embodiment.

FIG. 23 is a perspective view of the bracket according to the second embodiment.

FIG. 24 is a perspective view of a shearing piece according to the second embodiment.

[Explanation of symbols]

 A Abutment B Bolt F Lower flange L Parapet P Bridge pier S Steel girder W Web 10 Seismic isolation bridge preventive device 11 Base plate 11a Guide part 11b Shear hole 11c Bolt hole 12 Seismic isolation rubber 12a Shear rubber 12b Steel plate 12c Shear hole 12d Rubber layer 13 Plate Side shearing piece 14 Bracket 14a Mounting plate 14b Stiffening plate 14c Upper plate 14d Lower plate 14e Bolt hole 15 Anchor bolt 16 Support plate 16a Shearing hole 16b Vertical plate 16c Horizontal plate 17 Bracket side shearing piece 20 Seismic isolation bridge protection device 21 Base plate 22 Seismic isolation rubber 23 Base plate side shearing piece 24 Bracket 26 Support plate 27 Bracket side shearing piece 40 Seismic isolation bridge preventer 41 Base plate 42 Seismic isolation rubber 42a Steel plate 42d Shear hole 43 Shearing piece 44 Bracket 44a Mounting piece 44b Shearing hole 44c Anchor hole 45 Anchor bolt 46 Seat plate

Claims (9)

[Claims] 1. A seismic isolation bridge preventive device that is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling, and is a seismic isolation bridge preventive device that isolates the bridge girder, the base plate being fixed to the end of the bridge girder, and the base plate. A seismic isolation bridge preventive device, comprising: a seismic isolation rubber to be fixed and a bracket fixed to a pier or abutment, to which the seismic isolation rubber is fixed. 2. A seismic isolation bridge preventive device that is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling off and seismically isolates the bridge girder. A base plate having a shear hole provided on the surface opposite to the surface on the bridge girder side, a seismic isolation rubber having a shear hole provided on the surface on the bridge girder side attached to the base plate, and a shear hole of the seismic isolation rubber A seismic isolation falling bridge prevention device comprising: a shearing piece that can be fitted into a shearing hole of the base plate; and a bracket that is fixed to a bridge pier or abutment and to which the seismic isolation rubber is fixed. 3. A seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling, and is a seismic isolation bridge preventive device for isolating the bridge girder, the base plate being fixed to an end of the bridge girder, and the base plate. The seismic isolation rubber that has a shear hole on the surface opposite to the surface on the bridge girder side in the fixed state, and the bridge girder side that is fixed to the pier or abutment and to which the seismic isolation rubber is attached A seismic isolation bridge preventive device comprising: a bracket having a shear hole on its surface; and a shearing piece that can be fitted into the shearing hole of the bracket and the shearing hole of the seismic isolation rubber. 4. A seismic isolation bridge preventive device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling off, and which seismically isolates the bridge girder, which is fixed to the end of the bridge girder in a fixed state. A base plate having a shear hole on the surface opposite to the bridge girder side, a seismic isolation rubber having shear holes on both surfaces attached to the base plate, and fixed to a bridge pier or abutment. A bracket to which a seismic rubber is attached, in which a shear hole is provided on the surface of the bridge girder side, a shear hole that can be fitted into the shear hole of the seismic isolation rubber, and a shear hole of the base plate, and a shear hole of the bracket A seismic isolation bridge preventive device, comprising: a shearing piece that can be fitted into the shearing hole of the seismic isolation rubber. 5. A seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent a bridge from falling off and seismically isolates the bridge girder, the base plate fixed to an end of the bridge girder, and the base plate. A seismic isolation rubber to be fixed, a support plate fixed to the seismic isolation rubber, and a bracket fixed to a bridge pier or abutment and fixed to the support plate, are installed in a lower portion of the base plate. A seismic isolation bridge preventive device comprising: a guide portion that extends in a bridge axis direction of the bridge girder and guides a lower portion of the support plate. 6. A seismic isolation falling bridge prevention device which is fixed to a bridge girder and a bridge pier or abutment to prevent falling bridges, and which seismically isolates the bridge girder, which is fixed to the end of the bridge girder in a fixed state. A base plate having a shear hole provided on the surface opposite to the surface on the bridge girder side, a seismic isolation rubber having a shear hole provided on the surface on the bridge girder side attached to the base plate, and a shear hole of the seismic isolation rubber A shearing piece that can be fitted into the shearing hole of the base plate; a support plate fixed to the seismic isolation rubber; and a bracket that is fixed to the pier or abutment and to which the support plate is fixed. A seismic isolation bridge preventive device, characterized in that a guide portion extending in the bridge axis direction of the bridge girder for guiding the lower portion of the support plate is provided at the lower portion of the base plate in the state. 7. A seismic isolation falling bridge prevention device which is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling, and which is a seismic isolation of the bridge girder, wherein the base plate is fixed to an end of the girder, and the base plate is attached to the base plate. Fixed, a seismic isolation rubber provided with a shear hole on the surface opposite to the surface on the bridge girder side in a fixed state, and a shear hole provided on the surface on the bridge girder side to which the seismic isolation rubber is attached The supporting plate, a shearing hole of the supporting plate, a shearing piece that can be fitted into the shearing hole of the base isolation rubber, and a bracket that is fixed to the pier or abutment and to which the supporting plate is fixed. A seismic isolation bridge preventive device, characterized in that a guide portion extending in the bridge axis direction of the bridge girder and guiding the lower portion of the support plate is provided in the lower portion of the base plate in the opened state. 8. A seismic isolation bridge preventive device that is fixed to a bridge girder and a pier or abutment to prevent a bridge from falling, and is a seismic isolation bridge preventive device that isolates the bridge girder. A base plate having a shear hole provided on the surface opposite to the bridge girder side, a seismic isolation rubber provided with a shear hole on each of the two surfaces attached to the base plate, and a shear hole of the seismic isolation rubber, A shearing piece that can be fitted into the shearing hole of the base plate, a support plate to which the seismic isolation rubber is attached and a shearing hole is provided on the surface of the bridge girder side, and a fixed to a bridge pier or abutment that fixes the support plate. A bracket, a shear hole of the support plate, and a shearing piece that can be fitted into the shearing hole of the base isolation rubber, and the bridge of the bridge girder is installed below the base plate in the installed state. Extend in a direction, the seismic isolation girder prevention device, wherein a guide portion bottom is guided in the support plate is provided. 9. The shear hole has a length in a bridge axis direction longer than a length of the shearing piece in a bridge axis direction of the bridge girder,
9. The seismic isolation falling bridge prevention apparatus according to claim 1, wherein the shearing piece is slidable in the bridge axial direction inside the shearing hole.