JP4331184B2 - Fall bridge prevention device with displacement adjustment function - Google Patents

Description

  The present invention is used together with a load bearing device such as an elastic bearing device for load bearing of an upper structure, and prevents a bridge or other structure from being displaced by a horizontal seismic force and falling from the lower structure such as an abutment. More particularly, the present invention relates to a fall prevention apparatus with a displacement adjustment function that allows expansion and contraction due to a temperature change of an upper structure.

  As shown in FIG. 10, a stopper device for preventing a falling bridge is conventionally used to prevent a structure such as a bridge supported by a rubber bearing from dropping from a lower structure such as an abutment or a pier by a strong horizontal seismic force. Further, an upward locking protrusion 34 is integrally provided at the center of the upper surface of the lower stopper member 33 fixed to the upper portion of the lower structure 23, and the lower surface of the upper stopper member 35 fixed to the lower portion of the upper structure 22. A locking recess 36 having a downward opening is provided in the center of the upper portion, the upward protrusion 34 is disposed in the downward opening recess 36, and the upper structure 22 is allowed to extend and contract between the upward protrusion 34 and the downward opening recess 36. A displacement limiting stopper device 37 that limits the movement of the upper structure 22 with a structure provided with a gap L in the bridge axis direction is known (for example, see Patent Document 1).

  In addition, conventionally, it is also known that a falling bridge prevention device is provided between the upper structure 22 and the lower structure 23 separately from the displacement limiting stopper device 37 (for example, Non-Patent Document 1). reference).

  In addition, in the past, when newly installing a fallen bridge prevention device or the like into a bridge pier, it is almost always necessary to reinforce the bridge pier, and when a bridge pier is to be retrofitted, the river pier is divided between the river and the pier. If a partition wall is installed and a reinforcing steel plate is erected on the outside of the pier to reinforce the pier, the construction of the partition wall will be expensive, and installation costs such as installation of the equipment and reinforcement of the pier will be marked. There is a problem of becoming higher.

In addition, as a structure for preventing falling bridges, PC steel materials such as cables and steel bars, which are arranged in a prominent position on the appearance of the upper structure or lower structure, are interposed between the upper and lower structures, or steel brackets. Since there is a gap in the lower structure so as to face the upper structure with a gap, there was a problem on the landscape such as worsening the landscape.
Fairness 02-48494 Road Bridge Specification and Explanation V Seismic Design Edition December 1996 Japan Road Association P215-219

In the case of the prior art, the falling bridge prevention device and the displacement limiting device are installed separately and independently, so it is necessary to provide a reinforced mounting portion for supporting each reaction force on the lower structure. There is a problem that the construction cost becomes very high.
Further, in the conventional case, PC steel such as cables and steel bars, which are conspicuous in appearance, are interposed between the upper and lower structures, or the steel bracket is opposed to the upper structure with a gap. There was a problem on the landscape because it was installed in the substructure.
Also, in conventional bridges, the superstructure (girder) often collides with the parapet part at the top of the abutment and damages the parapet in the event of an earthquake, which requires a long construction period and a large repair cost. There is a problem that an overbridge prevention device having a structure in which the superstructure does not collide with the parapet is desired.
It is an object of the present invention to provide a falling bridge prevention device with a displacement adjustment function in which a falling bridge prevention device and a displacement limiting device are incorporated into one device in a compact manner.

In order to achieve the above object, in the falling bridge prevention device with displacement adjustment function of the first invention, a locking protrusion is provided on one of the upper stopper member and the lower stopper member, and a locking recess is provided on the other. In the falling bridge prevention device in which the locking protrusion is disposed in the locking recess and the upper stopper member and the lower stopper member are attached to the upper structure and the lower structure, respectively, the lower surface of the lower stopper member or the upper stopper An elastic layer that resists by shear deformation in the bridge axis direction is integrally fixed to any one of the upper surfaces of the member, a base plate is fixed to the elastic layer, and a bolt insertion hole of the stopper member to which the elastic layer is fixed, Between the bolt shaft part such as an anchor bolt for attaching the stopper member, which is inserted through the bolt insertion hole and has an elastic layer fixed thereto, to the structure, an earthquake Wherein the bridge axis direction of the displacement adjustment gap for causing the shear deformation of the elastic layer by the displacement of the bridge axis direction of the building is provided in the.
In the falling bridge prevention device with displacement adjustment function according to the second aspect of the present invention, a locking protrusion is provided on one of the upper stopper member and the lower stopper member, a locking recess is provided on the other, and the locking protrusion is provided. In the falling bridge prevention device, which is disposed in the recess for locking, and the upper stopper member and the lower stopper member are respectively attached to the upper structure and the lower structure, an elastic layer is fixed to the lower surface of the lower stopper member, and the elastic layer The base plate is fixed to the lower surface of the bolt, and between the bolt insertion hole of the lower stopper member and the bolt shaft portion such as an anchor bolt that is inserted into the bolt insertion hole and attaches the lower stopper member to the lower structure. A displacement adjustment gap in the bridge axis direction is provided for shear deformation of the elastic layer by displacement in the bridge axis direction of the superstructure.
According to a third aspect of the present invention, there is provided the fall prevention device with a displacement adjusting function according to the second aspect of the invention, wherein the elastic layer is shear-deformed and the upper and lower stopper members and bolt shaft portions such as anchor bolts in the bridge axis direction. In contact with each other to resist the movement of the superstructure in the bridge axis direction.
According to a fourth aspect of the present invention, in the falling bridge prevention device with a displacement adjustment function according to any one of the first to third aspects, the displacement limiting function by the shear deformation resistance in the bridge axis direction of the elastic layer, and the locking protrusion It is characterized by having both functions of a fallen bridge preventing function that engages with the inner surface of the locking recess and resists as a whole in the direction of the bridge axis.
According to a fifth aspect of the present invention, in the fallen bridge prevention device with a displacement adjustment function according to the fourth aspect of the invention, the fallen bridge prevention function functions after completion of the displacement by the displacement limiting function.
According to a sixth aspect of the present invention, in the fallen bridge prevention device with a displacement adjustment function according to any one of the first to fifth aspects, the first gap dimension between the locking projection and the locking recess, and the lower stopper The sum of the second gap dimension between the bolt shaft portion that fixes the member to the lower structure is the upper portion that is adjacent in series between the upper structure and the parapet of the abutment as the lower structure or in the bridge axis direction. It is characterized by being smaller than the third gap dimension between the structures.
Further, in the seventh invention, in the falling bridge prevention device with a displacement adjustment function according to any one of the second to sixth inventions, a bolt such as an anchor bolt fixed to the lower structure side across the lower stopper member and the base plate is provided. The bolt insertion hole of the lower stopper member is a long hole provided with a displacement adjustment gap in the bridge axis direction, and the inner surface of the bolt insertion hole of the base plate and the outer surface of the bolt shaft portion are arranged close to each other. It is characterized by being.
In the eighth invention, in the falling bridge prevention device with a displacement adjustment function according to any one of the second to seventh inventions, the gap between the bolt insertion hole of the lower stopper member and the bolt shaft portion inserted through the hole is the above-mentioned In a state where the locking projection is engaged with the inner surface of the locking recess, the gap between the upper structure and the abutment side parapet or between the upper structures adjacent in series in the bridge axis direction is less than the gap in the bridge axis direction. It is characterized by its dimensions.

According to the first invention or the second invention, it is a falling bridge prevention device with a displacement adjusting function in which an elastic layer is integrally incorporated on either the lower surface of the lower stopper member or the upper surface of the upper stopper member, or under the lower stopper member. Since it is a fall prevention device with a displacement adjustment function that integrally incorporates an elastic layer on the side or a base plate in this side, the device is more compact than when a fall prevention device and a displacement limiting device are provided independently as in the past. The construction cost of the fall prevention device with the displacement adjustment function can be significantly reduced, and the installation of the fall prevention device with the displacement adjustment function is facilitated because only one device needs to be installed. And it can be constructed at low cost.
In addition, since an elastic layer capable of shearing deformation is integrally provided on the lower surface of the lower stopper member or the upper surface of the upper stopper member, an elastic layer that can ensure a repeated function against seismic force at the seismic intensity level that requires displacement limitation For the seismic force exceeding the displacement limiting function due to the shear deformation of the elastic layer, the locking protrusion on the lower stopper member (or the upper stopper member) is connected to the upper stopper member (lower stopper member). ) To prevent the superstructure from being dropped.
In addition, since the elastic layer and the base plate are arranged below the lower stopper member or above the upper stopper member, there are obtained effects such as that the scenery is not significantly hindered as in the prior art.
According to the third invention, with the elastic layer being shear-deformed, the upper stopper member, the lower stopper member, and the bolt shaft portion such as an anchor bolt are brought into contact with each other in the bridge axis direction to move the upper structure in the bridge axis direction. Because it is made to resist, the displacement adjustment function to limit the displacement of the upper structure due to the shear deformation resistance of the elastic layer, and the upper stopper member, the lower stopper member and the anchor bolt etc. directly contact with the bolts such as anchor bolts The structure can resist the movement of the structure in the bridge axis direction, and the upper structure can be reliably prevented from falling from the lower structure.
According to the fourth invention, the displacement limiting function by the shear deformation resistance of the elastic layer in the bridge axis direction, and the locking protrusion engages with the inner surface of the locking recess and resists as a whole in the bridge axis direction. Since it has both functions of preventing a falling bridge, it can be a device that has two functions of a displacement limiting function due to shear deformation resistance of the elastic layer and a falling bridge preventing function, and is independent. Therefore, it is cheaper than installing each device, and the installation space is small.
According to the fifth aspect of the present invention, since the falling bridge prevention function functions after completion of the displacement by the displacement limiting function, after the upper structure is securely buffered by the displacement limiting function by the shear deformation resistance of the elastic layer, Since the falling bridge prevention device functions, the horizontal force in the bridge axis direction input to the upper structure or the lower structure in the falling bridge prevention device with the displacement adjustment function can be reduced.
According to the sixth invention, the first gap dimension between the locking projection and the locking recess and the second gap dimension between the bolt shaft portion that fixes the lower stopper member to the lower structure. Is smaller than the third gap dimension between the upper structure and the parapet of the abutment as the lower structure or between the upper structures adjacent in series in the bridge axis direction. Does not collide directly with the parapet or between the upper structures, but transmits horizontal force from the abutment or the pier as the lower structure to the ground or from the parapet part of the abutment as the lower structure to the back soil. It is possible to expect a buffer support action by the ground.
According to the seventh aspect of the present invention, the bolt insertion hole of the lower stopper member is a long hole provided with a displacement adjustment gap in the bridge axis direction, and the bolt insertion hole inner surface of the base plate and the bolt shaft outer surface are close to each other. Since it is arranged, the displacement adjusting gap can be easily formed simply by providing a long hole in the lower stopper member.
According to the eighth invention, before the upper structure such as the girder collides with the parapet of the lower structure or before the upper structures collide with each other, the fall bridge prevention function acts. The possibility of colliding with the parapet on the abutment and damaging the parapet can be eliminated, and the possibility of damaging the upper structure by colliding with each other and colliding with each other can be eliminated. it can. Therefore, there is no parapet repair work or superstructure repair work, and the bridge restoration work is facilitated.

  Next, the present invention will be described in detail based on the illustrated embodiment.

  1 to 8 show a fall prevention device 7 with a displacement adjustment function according to an embodiment of the present invention. The fall prevention device 7 with a displacement adjustment function according to this embodiment is a constant temperature change of an upper structure. Displacement adjustment which has a displacement adjustment (displacement restriction) function in cooperation with a part of the function of the falling bridge prevention device 30 which is allowed to extend and contract and which has a function to prevent the falling bridge, and a part thereof. It is set as the structure with which the part of the apparatus 9 was integrated.

  The falling bridge prevention device 30 includes a steel lower stopper member 1 attached to the lower structure 23 via the elastic layer 5 and the base plate 6, and a steel upper stopper member 3 fixed to the upper structure 22. Consists of.

In the illustrated embodiment, an elastic layer 5 such as rubber is integrally fixed to the lower surface of the lower stopper member 1 made of steel by baking or the like, and the lower surface of the elastic layer 5 is made of a rectangular steel plate. A base plate 6 is integrally provided by baking or the like. As shown in FIGS. 1 and 5, holes or long holes 13 are provided at the same position so as to extend in the bridge axis direction at the four corners of the lower stopper member 1, the elastic layer 5, and the base plate 6. .
At the four corners of the lower stopper member 1 and the elastic layer 5, elongated holes 13 are provided at the same position so as to extend in the bridge axis direction, and each elongated hole 13 is fixed to the lower structure 23 side. The upper shaft portion of the bolt or anchor bolt (in the case of illustration) 8 is inserted and arranged.
The holes at the four corners of the base plate 6 are circular holes, and the upper shafts of bolts or anchor bolts (in the case of illustration) 8 that are fixed to the lower structure 23 side are inserted in close proximity.

An upper portion of the lower stopper member 1 in the vicinity of the long hole 13 through which the anchor bolt 8 is inserted is a planar rectangular projection 17 having a flat upper surface, and the anchor bolt 8 is disposed on the upper surface of the projection 17. A sliding bearing plate 20 made of an ethylene tetrafluoride plate is inserted through the upper surface of the sliding bearing plate 20. A pressing washer 15 for holding the anchor bolt 8 is disposed on the upper surface of the sliding bearing plate 20. The downward locking projections 24 of both side end portions of 15 are engaged with the side surfaces of the projection 17 in the direction perpendicular to the bridge axis, and the nut 16 is attached to the anchor bolt 8 on the upper surface of the slide washer 15 for pressing. The lower stopper member 1, the elastic layer 5, and the base plate 6 are attached to the lower structure 23 by being screwed.
Since the slide washer 15 is provided with a sliding support plate 20 made of an ethylene tetrafluoride plate having a small coefficient of friction with a steel material, the lower stopper member 1 is relatively relative to the anchor bolt 8 in the direction of the bridge axis. Has been made movable.

The gap G in the bridge axis direction between the anchor bolt 8 and the lower stopper member 1 and the long hole 13 of the elastic layer 5 has a gap dimension between the parapet 25 and the end surface of the upper structure 22 in the abutment 23a. The gap is smaller than G1.
Therefore, when the horizontal force in the bridge axis direction acts during the earthquake and the upper structure 22 and the lower structure 23 are relatively displaced in the bridge axis direction, the upper structure (girder) 22 is located at the upper part of the abutment. Before colliding with the parapet 25, the inner surface of the long hole 13 in the lower stopper member 1 comes into contact with the anchor bolt 8 to cause the elastic deformation of the elastic layer 5, and the buffer is supported by the shear deformation of the elastic layer 5. Yes.

  At the center of the upper surface 10 of the lower stopper member 1, an upward locking projection 2 having a circular cross section is integrally provided, and the bridge axis direction of the upward locking projection 2 and the downward opening recess 4 of the upper stopper member 3 is provided. A gap G2 is provided on both sides of the upper structure 22 so that the upper structure 22 can be expanded and contracted by a constant temperature change.

  Although not shown in the drawing, a plurality of (for example, four) rubber positioning pieces are provided on the upper surface 10 of the lower stopper member 1 around the upward protrusion 2 at intervals in the protrusion peripheral direction. A lower part of a rubber positioning piece such as a hollow cylinder is fixed to the lower stopper member 1. The rubber positioning piece provides a gap between the upper surface 10 of the lower stopper member 1 and the lower surface 19 of the upper stopper member 3 (even if the rubber positioning piece is present, the vertical load of the upper structure is Does not bear.)

  A female screw hole 12 is provided in the top plate 11 at the top of the steel upper stopper member 3, and a male screw portion at the lower end of an upper anchor member 18 made of a steel rod having a flange at the upper end is screwed into the female screw hole 12, and The upper anchor member 18 is fixed to the top plate 11 by welding, and a locking recess 4 having an oval downward opening extending in the bridge axis direction is provided at the center of the lower surface 19 of the upper stopper member 3. ing.

Further, an upper portion of the upward protrusion 2 is disposed in the downwardly engaging locking recess 4, and an inner surface of the downwardly opening locking recess 4 in the bridge axis direction and an outer surface of the upward locking protrusion 2 are arranged. A gap G2 is provided between the upper structure 22 to allow expansion and contraction due to temperature change of the upper structure 22 (see FIG. 2). 2 is movable in the gap in the bridge axis direction of the locking recess 4 of the downward opening.
Further, when the upper structure 22 or the lower structure 23 moves relatively in the bridge axis direction during an earthquake or the like, the locking protrusion 2 and the inner surface in the bridge axis direction of the locking recess 4 come into contact with each other. When the base plate 6 moves as a unit, the base plate 6 is locked to the anchor bolt 8 and is fixed to the lower structure 23 side, so that the elastic layer 5 is shear-deformed in the bridge axis direction. Further, when the upper structure 22 or the lower structure 23 moves relatively in the bridge axis direction, the anchor bolt 8 engages with the inner surface of the long hole 13 of the lower stopper member 1, and the upper structure 23. Will be restrained from moving in the direction of the bridge axis (details will be described later).

  Although not shown, the falling bridge prevention device 7 with a displacement adjustment function of the present invention is used together with a support device such as an elastic support device that bears a vertical load of an upper structure (not shown). The vertical load of the upper structure 22 is supported.

  Next, the operation of the falling bridge prevention device 7 with the displacement adjustment function of the first embodiment of the present invention will be described.

  When the upper structure 22 on which a vertical load is supported by a sliding elastic bearing device (not shown) is expanded or contracted in the direction of the bridge axis due to a constant temperature change, the upward locking protrusion 2 and the upper stopper member 3 are used. The upper structure 22 is allowed to expand and contract in the bridge axis direction in the gap G2 on both sides in the bridge axis direction with the downward opening recess 4.

  In addition, for seismic motion at the seismic intensity level in which the upper structure 22 and the lower structure 23 move relative to each other in the bridge axis direction, as shown in FIG. When the upward locking projection 2 in the lower stopper member 1 is engaged, further displacement in the bridge axis direction causes shear deformation of the elastic layer 5 and functions as a displacement limiting device by the shear deformation resistance of the elastic layer 5 Can be made.

  Further, in an earthquake motion in which a larger horizontal force (indicated by an arrow in FIG. 6) acts, the state shown in FIG. 6, that is, the elastic layer 5 is shear-deformed, and the lower stopper member 1 and the anchor bolt 8 are used. Are in contact with each other, and the upper stopper protrusion 3 and the upper stopper protrusion 3 in the lower stopper member 1 are in contact with each other, the anchor bolt 8 and the lower stopper member 1 are connected between the upper structure 22 and the lower structure 23. Since all the upper stopper members 3 are in contact with the steel material, the whole is united, and the upper structure 22 is detached from the elastic support device that supports the vertical load and falls (drops) from the lower structure. It can be made to act as a fallen bridge prevention device which prevents In addition, the gap G between the bolt insertion elongated hole 13 of the lower stopper member 1 and the bolt shaft portion of the anchor bolt 8 inserted through the hole 13 is related to the inner surface of the locking recess 4. In the combined state, the size is not more than the gap G1 in the bridge axis direction between the upper structure 22 and the parapet on the abutment 23a side, so that the upper structure 22 is prevented from colliding with the parapet 25 in the abutment 23a. can do.

  Also, in the embodiment of the present invention, the falling bridge prevention device functions in a state after the horizontal force input to the structure is reduced during the earthquake by deforming the elastic layer 5 by shearing force. There is an advantage that the burden on the stopper member 3 and the lower stopper member 1 can be reduced. On the other hand, in the case of the conventional apparatus shown in FIG. 10, since it functions as a stopper at the stage of the initial displacement limiting function, the burden on the locking projection 34 is large, and accordingly, the upper structure 22 and the lower structure The object 23 must be strongly reinforced.

  Further, the horizontal force P acting on the abutment 23a from the upper structure 22 or the like in the above case is configured to be supported by the back soil 27 provided on the back side of the abutment 23a as indicated by an arrow Q in FIG. Has been. That is, in the abutment 23 a in which the back soil 27 is filled on the back surface of the parapet 25, the horizontal force transmitted from the upper structure 22 to the falling bridge prevention device 7 with the displacement adjustment function at the time of the earthquake is It can transmit efficiently from the back to the ground, and the back soil 27 can be used effectively.

  As in the above-described embodiment, it is only necessary to install the fall prevention device 7 with a displacement adjustment function only on the abutment 23a, and there is no burden on the intermediate pier 23b between the abutments 23a. Alternatively, there is an advantage that these seismic reinforcements can be omitted when the pier 23b itself supports the end portion of the upper structure 22 composed of continuous girders.

  According to the embodiment, with the elastic layer 5 being subjected to shear deformation, the upper stopper member 3, the lower stopper member 1, and the bolt shaft portions such as the anchor bolts 8 are brought into contact with each other in the bridge axis direction, thereby Since it is made to resist the movement in the axial direction, a displacement adjusting function for limiting the displacement of the upper structure 22 by the shear deformation resistance of the elastic layer 5, the upper stopper member 3, the lower stopper member 1, and the anchor bolt 8. The direct contact of the bolts or the like makes it possible to firmly resist the movement of the upper structure 22 in the bridge axis direction, and to reliably prevent the upper structure 22 from falling from the lower structure 23.

  According to the embodiment, the displacement limiting function by the shear deformation resistance in the bridge axis direction of the elastic layer 5 and the locking protrusion 2 engage with the inner surface of the locking recess 4 so that the whole is integrated in the bridge axis direction. Therefore, an apparatus having two functions of a displacement limiting function by a shear deformation resistance of the elastic layer 5 and a function of preventing a falling bridge is provided in one apparatus. In addition to being able to install each device independently, it is less expensive and requires less space for installation.

  According to the above embodiment, the displacement limiting function can be ensured until the shear deformation of the elastic layer 5 is completed, and the fall prevention function functions after the displacement is completed by the displacement limiting function. After the upper structure is securely buffered by the displacement limiting function based on the shear deformation resistance, the falling bridge prevention device is made to function. Therefore, the bridge that is input to the upper structure 22 or the lower structure 23 is input to the falling bridge prevention device with the displacement adjustment function. The horizontal force in the axial direction can be reduced.

According to the embodiment, between the dimension of the first gap G2 between the locking projection 2 and the locking recess 4 and the bolt shaft portion that fixes the lower stopper member 1 to the lower structure 23. Is smaller than the size of the third gap G1 between the upper structure 22 and the abutment parapet 25 as the lower structure 23, so that the upper structure 22 A horizontal force can be transmitted from the abutment as the lower structure 22 to the back soil (ground) 27 or from the parapet portion 25 in the abutment as the lower structure 23 to the back soil without directly colliding with the parapet 25. It is possible to exert a buffer support action by the ground.
In addition, in the crossing part of the girders shown in FIG. 9, since two upper structures 22 are installed in series in the bridge axis direction, two upper structures 22 and one lower structure 23 are provided between each upper structure 22 and one lower structure 23. In this case, a first gap dimension G2 between the locking projection 2 and the locking recess 4 and the lower stopper member 1 are installed. Is smaller than the third gap dimension G1 between the upper structures 22 adjacent to each other in series in the bridge axis direction. More preferably, the dimensions of the first gaps G2 between the locking projections 2 and the locking recesses 4 in the falling bridge prevention devices 7 with displacement adjustment function attached to the upper structures 22 and the lower parts Each second between the bolt shaft portion that fixes the stopper member 1 to the lower structure 23. By making the sum of the gap size G smaller than the size of the third gap G1 between the upper structures 22 adjacent in series in the bridge axis direction, the possibility of the upper structures 22 colliding directly with each other is eliminated. A horizontal force can be transmitted from the lower structure 22 to the ground 27, and a buffer support action by the ground 27 can be exhibited.

  As described above, in the form in which the structure expansion / contraction allowance gap G is provided between the both ends of the downward opening concave portion 4 and the upward projection 2 in the falling bridge prevention device 30, the upper structure 22 expands and contracts due to a temperature change. When it occurs, it can freely expand and contract.

  When installing the fall prevention device 7 with the displacement adjustment function as described above, first, the downward opening recess 4 in the fall bridge prevention device 7 with the displacement adjustment function is extended in the longitudinal direction of the upper structure 22 such as a concrete bridge girder to be built. In such a state, the anchor plate 8 protruding on the lower structure 23 is inserted into the base plate 6, the elastic layer 5, and the long hole 13 of the lower stopper member 1. The sliding support member 20 and the slide washer 15 are mounted, and the nut 16 is screwed into the anchor bolt 8. Next, after assembling a grooved mold (not shown) for constructing the upper structure 22 and fitting the upper stopper member 3 into the opening provided in the bottom plate of the mold, The upper structure 22 is constructed by placing structural concrete in the formwork.

  Also on the abutment 23 a, although not shown on the side of the falling bridge prevention device 30, a sliding elastic that bears the vertical load of the upper structure 22 between the lower structure 23 and the structure 22. A bearing device is installed.

Although not shown in the drawings, as a modification of the above-described embodiments, the size of the gap G2 in the bridge axis direction between the locking projection 2 and the locking recess 4 and the bolt shaft portion such as the anchor bolt 8 And the lower stopper member 1 and the length G of the gap G of the long hole 13 of the elastic layer 5 in the bridge axis direction are set as shown in (1) to (2) below, with a displacement adjustment function of various deformation forms The falling bridge prevention device 7 can be configured.
(1) The gap G2 is set to a gap size G2 that allows for the amount of expansion and contraction when the temperature of the upper structure 22 changes, and the gap G is set as a gap for limiting displacement accompanied by shear force deformation resistance of the elastic layer 5 and sheared during an earthquake. In a state where the elastic resistance function due to deformation is maximized, the anchor bolt 8, the lower stopper member 1, and the upper stopper member 3 are in contact with each other, and thereafter the whole is integrated with respect to movement in the bridge axis direction. A fall prevention device with a displacement adjustment function in a form that is made to act as a fall prevention device.
(2) The gap G2 is set to a gap dimension G2 that allows for the amount of expansion / contraction when the temperature of the upper structure 22 changes and the displacement of the upper structure 22 in the bridge axis direction during an earthquake (in this case, displacement adjustment) It resists horizontal displacement in the bridge axis direction of the upper structure 22 due to shear deformation of the elastic layer of the elastic bearing device that is used together with the function-equipped bridge prevention device 7 and bears the vertical load of the upper structure 22. , The gap G is used as a gap for limiting displacement or preventing a falling bridge during an earthquake accompanied by shear force deformation resistance of the elastic layer 5, and when the elastic resistance function due to shear deformation is exerted to the maximum during an earthquake, the anchor bolt 8 and the lower part The stopper member 1 and the upper stopper member 3 are in a state of contact with each other, and then the displacement adjustment in a form in which the whole is integrated to act as a falling bridge prevention device for the movement in the bridge axis direction. Noh with a bridge collapse prevention device.

  In the embodiment of the present invention, the lower structure 23 and the upper structure 22 may be steel structures. In this case, although not shown, the anchor bolt 8 is replaced by a bolt instead of the anchor bolt 8. The stopper member 1 or the upper stopper member 3 may be attached to each structure.

  The rubber positioning piece is necessary only for positioning the lower stopper member 1 and the upper stopper member 3 in the vertical direction and providing a predetermined vertical gap G therebetween. The rubber positioning piece may be omitted after the upper structure 22 is installed and the lower stopper member 1 that does not bear the vertical load of the structure 22 is installed.

  When carrying out the present invention, a steel plate is embedded in the lower end portion of the elastic layer 5 and the steel plate is fixed to the lower structure 23, or the lower portion of the elastic layer 5 is formed of hard rubber or the like, In the form in which the lower support column is disposed in the recess provided in the lower structure 23, the base plate 6 can be omitted.

  In carrying out the present invention, when the upper structure 22 is a steel structure, the upper stopper member 3 may be fixed to the upper structure 22 by welding or bolts or bolts and nuts. In the above case, the upper stopper member 3 is integrally provided with a flange projecting in the lateral direction, and the peripheral edge of the flange is fixed by welding, or a bolt insertion hole is provided in the flange to the upper structure 22 with a bolt or the like. It may be fixed.

  Further, when the present invention is carried out, an outward flange projecting in the lateral direction perpendicular to the bridge axis is integrally provided at the distal end portion (upper end portion in the illustrated case) of the locking projection 2, and the lower end of the upper stopper member 3 is provided. An inward flange projecting inwardly on the peripheral edge is integrally provided at a slightly lower level than the outward flange, and the outward flange is used as an inward flange when the upper stopper member moves in the bridge axis direction at all times and during earthquakes. You may make it engage.

  When the present invention is implemented, an elastic material such as rubber or synthetic resin can be used as the elastic layer 5, and the lower stopper member 1, the upper stopper member 3, and the anchor bolt 8 having the locking protrusions 2. As the steel material is used.

(Other variations)
When carrying out the present invention, although not shown in the drawings, the base plate 6, the elastic layer 5, the lower stopper member 1 side, and the upper stopper member 3 side in the above embodiments are vertically inverted so that the lower portion is the upper side. A member having an elastic layer 5 on the upper surface of the stopper member 1, that is, the upper stopper member 3, and a base plate 6 integrally formed on the upper surface of the elastic layer 5 is attached to the upper structure with bolts such as anchor bolts, and the upper stopper on the lower side. The member 3 may be fixed to the lower structure.
In the illustrated embodiment, a flange projecting in the bridge axis direction is integrally provided at the upper end of the upper stopper member 3, and an elastic layer 5 is fixed to the upper surface of the upper stopper member 3 and the projecting flange. The same steel plate as that of the base plate 6 is fixed, and the elastic layer 5 is attached to the upper structure so that it can be deformed by shear, the elastic layer 5 and the base plate 6 on the lower surface of the lower stopper member 1 are omitted, and the lower stopper The member 1 may be directly fixed to the lower structure 23.
That is, in the present invention, the locking protrusion 2 is provided on one of the upper stopper member 3 and the lower stopper member 1, the locking recess 4 is provided on the other, and the locking protrusion 2 is connected to the locking recess 4. In the falling bridge prevention device which is disposed inside and attaches the upper stopper member 3 and the lower stopper member 1 to the upper structure 22 and the lower structure 23, respectively, the lower surface of the lower stopper member 1 or the upper surface of the upper stopper member 3 Either one of them may be a fall prevention device with a displacement adjusting function in a deformed form in which the elastic layer 5 that resists by shear deformation in the bridge axis direction is integrally fixed.

It is a partial longitudinal cross-sectional side view which shows the state which installed the falling bridge prevention apparatus with a displacement adjustment function of one Embodiment of this invention. It is a vertical side view of the falling bridge prevention apparatus with a displacement adjustment function shown in FIG. 1, and is a vertical side view of the falling bridge prevention apparatus with a displacement adjustment function in a form that allows movement of the upper structure in the bridge axis direction. It is a vertical front view of the falling bridge prevention apparatus with a displacement adjustment function shown in FIG. It is a top view of the falling bridge prevention apparatus with a displacement adjustment function shown in FIG. FIG. 2 is a partially cut-away cross-sectional plan view showing a part of the falling bridge prevention device with a displacement adjustment function shown in FIG. 1 removed. It is a vertical side view of the falling bridge prevention apparatus with a displacement adjustment function shown in FIG. It is a partially longitudinal side view showing the vicinity of a falling bridge prevention device with a displacement adjustment function installed on an abutment. It is a side view which shows the whole bridge provided with the falling bridge prevention apparatus with a displacement adjustment function of this invention. It is a partial vertical side view which shows the form applied to the crossing part of a girder. It is a partially longitudinal front view showing an example of a conventional stopper device.

DESCRIPTION OF SYMBOLS 1 Lower stopper member 2 Upward locking protrusion 3 Upper stopper member 4 Downward opening recessed recess 5 Elastic layer 6 Base plate 7 Falling bridge prevention device 8 with displacement adjustment function Anchor bolt 9 Displacement adjustment device 10 Upper surface 11 Top plate 12 Female screw Hole 13 Long hole 15 Slide washer 16 Nut 17 Protruding portion 18 Upper anchor member 19 Lower surface 20 Sliding bearing plate 22 Upper structure 23 Lower structure 23a Abutment 23b Intermediate bridge pier 24 Downward locking projection 25 Parapet 26 Bearing device 27 Back soil 30 Falling bridge prevention device 33 Lower stopper member 34 Upward locking projection 35 Upper stopper member 36 Locking downward recess 37 Displacement limiting stopper device

Claims (8)

A locking protrusion is provided on one of the upper stopper member and the lower stopper member, a locking recess is provided on the other, and the locking protrusion is disposed in the locking recess, and the upper stopper member and the lower stopper member In the bridge-falling prevention device in which each is attached to the upper structure and the lower structure, an elastic layer that resists shear deformation in the bridge axis direction is integrated with either the lower surface of the lower stopper member or the upper surface of the upper stopper member. The base plate is fixed to the elastic layer, and the bolt insertion hole of the stopper member to which the elastic layer is fixed, and the stopper member that is inserted into the bolt insertion hole and fixed to the elastic layer are attached to the structure. Bridge shaft for shear deformation of the elastic layer by displacement in the direction of the bridge axis of the structure during an earthquake between bolt shaft parts such as anchor bolts Displacement adjustment function girder preventing apparatus characterized by displacement adjustment gap direction is provided.   A locking protrusion is provided on one of the upper stopper member and the lower stopper member, a locking recess is provided on the other, and the locking protrusion is disposed in the locking recess, and the upper stopper member and the lower stopper member Are attached to the upper structure and the lower structure, respectively, in which the elastic layer is fixed to the lower surface of the lower stopper member, the base plate is fixed to the lower surface of the elastic layer, the bolt insertion hole of the lower stopper member, The elastic layer is shear-deformed by displacement in the bridge axis direction of the upper structure during an earthquake between the bolt shaft part of an anchor bolt or the like that is inserted through the bolt insertion hole and attaches the lower stopper member to the lower structure. A bridge adjusting device with a displacement adjusting function, characterized in that a displacement adjusting gap in the direction of the bridge axis is provided.   In a state where the elastic layer is shear-deformed, the upper stopper member, the lower stopper member, and a bolt shaft portion such as an anchor bolt are brought into contact with each other in the bridge axis direction to resist the movement of the upper structure in the bridge axis direction. The fallen bridge prevention device with a displacement adjustment function according to claim 2, wherein:   Both a displacement limiting function by shear deformation resistance in the bridge axis direction of the elastic layer, and a falling bridge prevention function in which the locking protrusion engages with the inner surface of the locking recess and resists as a whole in the bridge axis direction The falling bridge prevention device with a displacement adjustment function according to any one of claims 1 to 3, wherein the function is provided.   5. The fall prevention device with a displacement adjustment function according to claim 4, wherein the fall prevention function is a two-stage type after completion of displacement by the displacement restriction function.   The sum of the first gap dimension between the locking projection and the locking recess and the second gap dimension between the bolt shaft portion that fixes the lower stopper member to the lower structure is the upper part. 6. The size of the third gap between the structure and the parapet of the abutment as the lower structure or between the upper structures adjacent in series in the bridge axis direction is smaller than the third gap size. A falling bridge prevention device with a displacement adjustment function according to any one of the above.   Bolts such as anchor bolts that are fixed to the lower structure side across the lower stopper member and the base plate are inserted, and the bolt insertion holes of the lower stopper member are elongated holes that are provided with displacement adjustment gaps in the bridge axis direction. The falling bridge preventing device with a displacement adjusting function according to any one of claims 2 to 6, wherein the inner surface of the bolt insertion hole of the base plate and the outer surface of the bolt shaft portion are arranged close to each other.   The gap between the bolt insertion hole of the lower stopper member and the bolt shaft portion inserted therethrough is such that the locking projection is engaged with the inner surface of the locking recess and the upper structure and the abutment side The displacement adjustment according to any one of claims 2 to 7, wherein the displacement is smaller than the gap dimension in the bridge axis direction between the parapets or between the upper structures adjacent in series in the bridge axis direction. Functional fall prevention device.

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