JP3727263B2 - Horizontal load elastic support device for functionally separated bearings for bridges - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a horizontal load elastic support device in a function-separated type support for bridges, and more particularly to a device having the latter function in a support in which a function for supporting a vertical load and a function for elastically supporting a horizontal load are separated. .
[0002]
[Prior art]
In recent years, a function-separated type bearing in which a function for supporting a vertical load and a function for elastically supporting a horizontal load have been developed in a bridge support. As a specific structure, the applicant previously proposed a structure comprising a sliding bearing that supports a vertical load and a horizontal load elastic support device that supports a horizontal load without supporting the vertical load (Japanese Patent Application 2001). -144766).
[0003]
The horizontal load elastic support device is usually installed by being sandwiched between two sliding bearings in the direction perpendicular to the bridge axis. In addition to supporting the horizontal load, this horizontal load elastic support device is required to have functions such as allowing the rotation of the upper structure and transmitting the upper lift force between the upper and lower structures. The horizontal load elastic support device satisfying such a function has a complicated structure and tends to increase in size, resulting in an increase in manufacturing cost.
[0004]
[Problems to be solved by the invention]
The present invention has been made based on the technical background as described above, and achieves the following object.
An object of the present invention is to provide a horizontal load elastic support device in a function separation type support for a bridge which satisfies a required function, has a simple structure and is compact, and can keep the manufacturing cost low. is there.
[0005]
[Means for Solving the Problems]
The present invention employs the following means in order to achieve the above object.
That is, this invention is a horizontal load elastic support device that is installed between an upper structure and a lower structure and supports a horizontal load without supporting a vertical load,
An upper flange fixed to the lower surface of the upper structure, and an elastic flange having a flange plate fixed to the upper surface of the lower structure and disposed on the upper portion so as to be opposed to each other by a predetermined distance in the vertical direction. With
Key holes are respectively formed in the center portions of the upper flange and the flange plate, and a shear key that allows relative rotation in the vertical direction between the flange plate and the upper flange is fitted into these key holes,
The horizontal load elastic support device in the function separation type bridge support for bridges, wherein the outer periphery of the flange plate is fixed to the upper flange by a bolt that allows relative rotation of the flange plate and the upper flange in the vertical direction. It is in.
[0006]
More specifically, a soft rubber plate is interposed between the upper collar and the flange plate. In this case, the soft rubber plate may be an annular one disposed on the inner peripheral portion surrounding the key hole and the outer peripheral portion including the mounting position of the bolt.
[0007]
The outer periphery of the flange plate is formed with a plurality of bolt insertion holes having counterbore holes on the lower surface thereof, and the upper collar is formed with a bolt mounting hole at a position corresponding to the bolt insertion hole, The flange plate is inserted into the bolt insertion hole, fixed to the upper collar by a bolt screwed into the bolt mounting hole, and the head of the bolt accommodated in the counterbore hole and the bottom of the counterbore hole A gap of a predetermined size is formed between the wall and the peripheral wall, and between the bolt main body portion inserted through the bolt insertion hole and the peripheral wall of the bolt insertion hole.
[0008]
The bolt insertion holes are provided with positioning pipes that are loosely fitted to the main body of the bolt and whose upper and lower ends engage with the outer peripheral edge of the bolt mounting hole and the head of the bolt, respectively. The lower outer periphery of the shear key fitted into the key hole of the flange plate is formed in a curved surface.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view in the direction perpendicular to the bridge axis showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA in FIG. The horizontal load elastic support device 1 is installed between an upper structure 2 and a lower structure 3 which are shown as concrete girders. Sliding bearings (not shown) are provided on both sides of the horizontal load elastic support device 1 in the direction perpendicular to the bridge axis. is set up. The vertical load of the upper structure 2 is transmitted to the lower structure 3 through the sliding bearing, and the vertical load does not act on the horizontal load elastic support device 1.
[0010]
The horizontal load elastic support device 1 includes an upper collar 4 and a rubber collar 5 as an elastic collar. The upper collar 4 is made of a square steel plate (the same applies to each steel plate described below), and a key hole 7 is formed at the center thereof. A plurality of anchor bolts 6 are screwed onto the upper collar 4, and the upper collar 4 is fixed to the lower surface of the upper structure 2 by the anchor bolts 6.
[0011]
The rubber cage 5 is made of laminated rubber obtained by laminating thick upper and lower steel plates 8 and 9 and thin intermediate steel plates 10 and a rubber layer 11 and vulcanized and bonded. Forming. A key hole 12 is formed at the center of the flange plate 8 so as to face the key hole 7. The upper and lower portions of the shear key 13 are fitted in the key holes 7 and 12. The outer periphery of the flange plate 8 is fixed to the upper collar 4 by a plurality of bolts 14.
[0012]
A ring plate 15 is fixed to the lower surface of the lower steel plate 9 at the center. The hole of the ring plate 15 forms a key hole 16 into which a key of a testing machine is fitted during a shear test. After the shear test, the keyhole 16 is closed with the same shape steel plate. A plurality of ring plates 17 are also fixed to the lower steel plate 9 on the outer periphery. Through these holes in the ring plate 17, the anchor bolt 18 is screwed to the lower steel plate 9, and the lower steel plate 9, that is, the rubber rod 5 is fixed to the upper surface of the lower structure 3 by the anchor bolt 18.
[0013]
The lower surface and outer periphery of the rubber bowl 5 are covered with the covering rubbers 19 and 20, and the lower surface and outer periphery of the flange plate 8 are also covered with the covering rubber 21. The covering rubber 19 on the lower surface of the rubber bowl 5 has the same thickness as the ring plates 15 and 17, and the ring plates 15 and 17 are cut out holes.
[0014]
As a result, the ring plates 15 and 17 and the covering rubber 19 are flush with each other. By adopting such a structure, a mold having a flat bottom surface can be used as a mold for vulcanization molding of the rubber bowl 5, and the manufacturing cost of the mold can be suppressed at a low cost. Although the ring plates 15 and 17 are not necessarily provided, in this case, the thickness of the lower steel plate 9 is increased by the thickness of the ring plates 15 and 17.
[0015]
The upper surface of the flange plate 8 is partially covered with two rectangular annular rubber plates 22 and 23 disposed on the inner and outer peripheral portions. The rubber plates 22 and 23 are soft ones having a static shear elastic modulus G of 4.5 to 6, and have a predetermined thickness of 5 to 10 mm. The inner peripheral rubber plate 22 is disposed so as to surround the key hole 12 on the upper surface of the flange plate 8, and the outer peripheral rubber plate 23 is disposed on the upper surface of the flange plate 8 including the mounting position of the bolt 14.
[0016]
The flange plate 8 is fixed to the upper flange 4 by the bolts 14 as described above. As a result, the rubber plates 22 and 23 are interposed between the upper flange 4 and the flange plate 8 with the lower surface of the upper flange 4 being in contact therewith. Will be. That is, the flange plate 8 is disposed opposite to the upper collar 4 by a distance d, and a vertical load is not transmitted to the rubber collar 5, so that the distance dimension d corresponding to the thickness of the rubber plates 22 and 23 is maintained. .
[0017]
FIG. 3 is an enlarged cross-sectional view showing the attachment structure of the shear key 13. The key hole 7 provided in the upper collar 4 has a larger diameter than the key hole 12 provided in the flange plate 8. The shear key 13 is formed in a curved surface 26 at a portion to be fitted into the key hole 7, that is, an upper outer periphery. Further, a gap 25 is formed between the upper part of the shear key 13 and the bottom wall of the key hole 7 in a state where the shear key 13 is fitted in the key holes 7 and 12. Thereby, the shear key 13 is freely rotatable relative to the upper collar 4 in the vertical direction.
[0018]
FIG. 4 is an enlarged cross-sectional view of the bolt 14 mounting structure. A plurality of bolt insertion holes 32 having counterbore holes 31 are formed on the outer periphery of the flange plate 8. On the other hand, a bolt mounting hole (screw hole) 33 is formed in the upper collar 4 at a position corresponding to the bolt insertion hole 32. The bolt 14 is inserted into the bolt insertion hole 32 and screwed into the attachment hole 33. At this time, an adhesive for preventing loosening is applied to the screw portion of the bolt 14, and the positioning pipe 35 is loosely fitted to the outer periphery of the main body portion 34. The upper and lower ends of the positioning pipe 35 are respectively engaged with the peripheral edge of the bolt mounting hole 33 and the washer 37 of the bolt head 36, whereby the rubber plates 22 and 23 are interposed between the upper flange 4 and the flange plate 8. A separation dimension d corresponding to the thickness is formed.
[0019]
In the bolt mounting structure, the bolt head 36 is accommodated in the counterbore 31, and gaps 38 and 39 of a predetermined size are formed between the bolt head 36 and the bottom wall and the peripheral wall of the counterbore 31, respectively. Has been. A gap 40 having a predetermined size is also formed between the bolt main body 34 and the peripheral wall of the insertion hole 32. Since the bolt head 36 is accommodated in the counterbore 31, it is difficult to see from the outside, and the appearance can be prevented from being damaged.
[0020]
Next, the operation of the above embodiment will be described. When a horizontal load acts on the upper structure 2 due to expansion / contraction due to temperature change or an earthquake, the horizontal load is transmitted to the rubber rod 5 via the shear key 13, and the rubber rod 5 undergoes shear deformation. The rubber cage 5 receives the horizontal load by this shear deformation and relaxes it.
[0021]
When the superstructure 2 rotates in the vertical direction due to a live load, there is a separation dimension d between the upper flange 4 and the flange plate 8, so the upper flange 4 rotates relative to the flange plate 8, and the rubber rod No live load is transmitted to 5. At this time, since the rubber plates 22 and 23 arranged between the upper collar 4 and the flange plate 8 are soft, relative rotation between the upper collar 4 and the flange plate 8 is not hindered.
[0022]
Further, since the shear key 13 is rotatable with respect to the upper collar 4, similarly, the relative rotation between the upper collar 4 and the flange plate 8 is not hindered. Further, since gaps 38, 39 and 40 are formed around the bolt 14, the relative rotation between the upper collar 4 and the flange plate 8 is not hindered with respect to the bolt 14 as well. As shown in FIG. 4, in order to make the rotation smooth, it is desirable to provide a gap 41 between the peripheral wall of the bolt insertion hole 39 formed in the outer peripheral rubber plate 23 and the positioning pipe 35.
[0023]
When a vertical upward force (uplift force) is applied to the upper structure 2 due to an earthquake, the upper lift force can be transmitted between the upper and lower structures 2 and 3 via the bolts 14 to prevent the upper structure 2 from falling. Can do.
[0024]
FIG. 5 is a cross-sectional view perpendicular to the bridge axis showing another embodiment. This embodiment is an example in which the upper structure 2 is made of steel girders. A sole plate 50 is fixed to the lower surface of the upper structure 2 by welding or the like. The upper collar 4 is disposed on the lower surface of the sole plate 50 and is fixed by bolts 52 that pass through the flange 51 of the upper structure 2 and are screwed to the sole plate and the upper collar 4.
[0025]
In addition to the key holes 7 and 12 of the upper collar 4 and the flange plate 8, a key hole 54 is provided in the sole plate 50, and the shear key 13 is fitted in these key holes 7, 12 and 54. The shear key 13 has a curved outer surface 26 at the lower periphery fitted into the keyhole 12 and a projection 53 formed on the lower surface. Thus, the shear key 13 is rotatable relative to the flange plate 8 in the vertical direction. Other configurations of the entire apparatus are the same as those in the above embodiment, and the operation is also the same.
[0026]
The above embodiments are merely examples, and the present invention can be modified in various ways. For example, in the above embodiment, a soft rubber plate is interposed between the upper collar and the flange plate, but the intended purpose can be achieved without this rubber plate. However, it is desirable to provide a rubber plate from the viewpoint of positioning of the flange plate with respect to the upper collar during installation (upper and lower gap adjustment), preventing rainwater and dust from entering the gap, and preventing rust. In this case, the entire surface of the flange plate may be covered with a rubber plate. However, as shown in the above embodiment, the inner cover rubber plate and the outer cover rubber plate may be partially covered to rotate the upper flange plate. It can be smooth.
[0027]
【The invention's effect】
As described above, according to the present invention, the structure required for the horizontal load elastic supporting device can be satisfied, the structure can be simplified and compact, and the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view perpendicular to a bridge axis showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is an enlarged sectional view showing a shear key mounting structure.
FIG. 4 is an enlarged cross-sectional view showing a bolt mounting structure for fixing an upper collar and a flange plate.
FIG. 5 is a cross-sectional view in a direction perpendicular to the bridge axis showing another embodiment.
[Explanation of symbols]
1: Horizontal load elastic support device 2: Upper structure 3: Lower structure 4: Upper rod 5: Rubber rod 7: Key hole 8: Upper steel plate (flange plate)
9: Lower steel plate 10: Middle steel plate 11: Rubber layer 12: Key hole 13: Shear key 14: Bolt 22: Inner rubber plate 23: Outer rubber plate 26: Curved surface 31: Counterbore 32: Bolt insertion hole 33: Bolt mounting hole 34: Bolt main body 35: Positioning pipe 36: Bolt head 38: Clearance 40: Clearance d: Separation dimension

Claims (5)

A horizontal load elastic support device that is installed between an upper structure and a lower structure and supports a horizontal load without supporting a vertical load,
An upper flange fixed to the lower surface of the upper structure, and an elastic flange having a flange plate fixed to the upper surface of the lower structure and disposed on the upper portion so as to be opposed to each other by a predetermined distance in the vertical direction. With
Key holes are respectively formed in the center portions of the upper flange and the flange plate, and a shear key that allows relative rotation in the vertical direction between the flange plate and the upper flange is fitted into these key holes,
The horizontal load elastic support device in the function separation type bridge support for bridges, wherein the outer periphery of the flange plate is fixed to the upper flange by a bolt that allows relative rotation of the flange plate and the upper flange in the vertical direction. . The horizontal load elastic support device for a function-separated support for a bridge according to claim 1, wherein a soft rubber plate is interposed between the upper collar and the flange plate. 3. The function separation type support for a bridge according to claim 2, wherein the soft rubber plate is formed of an annular member disposed on an inner peripheral portion surrounding the key hole and an outer peripheral portion including a mounting position of the bolt. Horizontal load elastic support device. On the outer periphery of the flange plate, a plurality of bolt insertion holes having counterbore holes on the lower surface side are formed,
A bolt mounting hole is formed in the upper collar at a position corresponding to the bolt insertion hole, and the flange plate is inserted into the bolt insertion hole and fixed to the upper collar with a bolt screwed into the bolt mounting hole. And
Between the head of the bolt housed in the counterbore and the bottom wall and peripheral wall of the counterbore, and between the main body of the bolt inserted into the bolt insertion hole and the peripheral wall of the bolt insertion hole 4. A horizontal load elastic support device for a functionally separated bridge support according to claim 1, wherein gaps of a predetermined size are formed between them. The bolt insertion hole is provided with positioning pipes that are loosely fitted to the main body of the bolt and whose upper and lower ends engage with the outer peripheral edge of the bolt mounting hole and the head of the bolt, respectively. The horizontal load elastic support apparatus in the function-separated type support for bridges according to claim 4.

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