JP4232454B2 - Damping structure of bridge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bridge, and more particularly to a superstructure damping structure.
[0002]
[Prior art]
The support installed between the superstructure and the substructure of the bridge plays a role of reliably transmitting the load of the superstructure to the substructure, and smoothly absorbs the expansion and contraction and rotation of the superstructure due to temperature change, creep, etc. It also plays a role.
[0003]
Such bearings are roughly classified into fixed bearings such as pin bearings having a load transmission function and a rotation function, and movable bearings such as roller bearings and rubber bearings having a horizontal movement function in addition to these.
[0004]
On the other hand, various technologies have been developed for vibration suppression of bridges, especially superstructures, during earthquakes.
[0005]
As a method of suppressing the vibration of the superstructure during an earthquake, the seismic isolation bearing, which is a kind of movable bearing, is installed between the superstructure and the substructure to reduce the input ground motion to the superstructure and A method to suppress relative displacement between the superstructure and the substructure, which are increased by seismicization, is generally used by a damping device, but the combination of a movable bearing and a damping device such as an active damper with high damping performance is also being researched and developed Yes.
[0006]
[Patent Document 1]
JP 2000-352113 A [0007]
[Non-Patent Document 1]
Obayashi Corporation, Technical Index, [online], [Search on December 10, 2002], Internet <URL: http://techs.obayashi.co.jp/techs/srb/show_detail?data=1432&freeword=%83 % 5F% 83% 93% 83% 70% 81% 5B & id = 0 & start = 10 & count = 5>
[0008]
[Problems to be solved by the invention]
However, the active damper described above applies a control force to the bridge to suppress the vibration of the bridge by analyzing the vibration detected by the sensor while detecting the vibration of the bridge with the sensor, or This is so-called active vibration control, in which the rigidity of the bridge is made variable and the rigidity is changed so that vibration of the bridge is also suppressed, so the overall system scale becomes large and it is not necessarily excellent in economic efficiency. It was difficult.
[0009]
In addition, due to such properties, there has also been a problem that it is difficult to say that it is excellent in terms of economy even if a large number of existing bridges are seismically reinforced.
[0010]
Furthermore, in the case of seismic reinforcement of existing bridges, if the support between the upper structure and the lower structure is not exchanged, the clearance for installing the attenuation device cannot be secured, resulting in the required attenuation performance. There has also been a problem that it may be necessary to give up the installation of the attenuation device provided.
[0011]
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a bridge damping structure that is excellent in economy and can be applied to existing seismic reinforcement.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the bridge damping structure according to the present invention has a long hole formed in the material axis direction and a friction material provided on both surfaces along the material axis direction as described in claim 1. The intermediate connection plate, a pair of side connection plates each having a stainless plate attached to one surface thereof, and the intermediate connection plate and the pair of side connection plates. A stainless steel plate that is slidably connected on the friction material along the material axis direction and is relatively movable along the material axis direction while being sandwiched between the plates, The coupling mechanism is inserted into the elongated hole formed in the intermediate coupling plate by inserting a bolt inserted through a disc spring into a bolt hole drilled in one of the pair of side coupling plates. In addition, the bolt hole drilled in the other side connecting plate A bridge damping structure using a brake damper configured to be screwed and fastened with a nut at the tip, wherein the unconnected end of the intermediate connecting plate, which is one end of the brake damper, is the upper structure of the bridge And a lower structure that supports the upper structure via a predetermined movable support, and is pin-coupled so as to be rotatable about a vertical axis, and the pair of side connection plates that are the other ends of the brake damper are not connected. In the vibration damping structure of a bridge in which an end is pin-joined to the other of the upper structure and the lower structure so as to be rotatable around a vertical axis ,
Two brackets each having both ends of the brake damper pin-joined so as to be rotatable about a vertical axis are joined to the upper structure and the lower structure via vertical displacement absorbing means , respectively.
[0015]
In the bridge vibration damping structure according to the present invention, the coupling mechanism is an intermediate coupling of a bolt inserted through a disc spring into a bolt hole drilled in one of the side coupling plates. It is configured to be inserted into a long hole formed in the plate and penetrated into a bolt hole drilled in the other side connecting plate so as to be screwed and fastened to the tip.
[0016]
Therefore, the clamping force of the intermediate connecting plate by the pair of side connecting plates, that is, the pressing force by the disc spring, should be set so that the dynamic friction coefficient between the stainless steel plate and the friction material becomes a desired magnitude. For example, when horizontal seismic motion is input to the bridge and a relative horizontal displacement occurs between the upper structure and the lower structure, the friction material provided on both sides of the intermediate connecting plate and the pair of side connecting plates are provided. The stainless steel plate slides to generate a frictional force corresponding to the above-described dynamic friction coefficient, which is converted into heat, thereby effectively suppressing the vibration of the superstructure. The pressing force by the disc spring can be arbitrarily set by appropriately adjusting the fastening torque of the bolt and nut.
[0017]
In addition, the unconnected ends of the intermediate connecting plate and the side connecting plate are pin-connected to the upper structure and the lower structure of the bridge so as to be rotatable about the vertical axis, so that even if horizontal earthquake motion acts on the bridge Only the axial force is transmitted to the intermediate connecting plate and the side connecting plate, and thus the vibration energy of the upper structure is surely absorbed by the sliding of the friction material and the stainless steel plate.
[0018]
The upper structure may be supported by a predetermined movable bearing such as a roller bearing, a rubber bearing, or a seismic isolation bearing so that the upper structure can be moved horizontally in the horizontal plane, particularly along the bridge axis direction.
[0019]
For example, when a rubber bearing is employed, the upper structure causes a relative vertical displacement with respect to the lower structure. In such a case, the brake damper is connected to the upper structure and the vertical structure through a vertical displacement absorbing means. If it is joined to the lower structure, the above-described relative vertical displacement can be absorbed by the vertical displacement absorbing means, and only axial force is transmitted to the intermediate connecting plate and the pair of side connecting plates, and friction The above-described energy absorption can be more effectively achieved by sliding between the material and the stainless steel plate.
[0020]
In the brake damper, the unconnected end of the intermediate connecting plate, which is one end thereof, is pin-joined to one of the upper structure and the lower structure, and the unconnected ends of a pair of side connecting plates, which are the other ends, are connected to the upper structure and the lower structure. As long as it is configured to be pin-bonded to the other, the arrangement location, arrangement direction, number of arrangements, etc. are arbitrary.
[0021]
For example, the substructure may be an abutment or a pier. In addition, a brake damper may be arranged alone along the bridge axis direction between the bridge girder as the upper structure and the abutment or pier as the lower structure, or a plurality of brake dampers may be arranged side by side. Furthermore, a plurality of brake dampers may be installed so as to be non-parallel to each other. According to such a configuration, the vibration of the superstructure can be absorbed not only in the bridge axis direction but in all directions.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a bridge damping structure according to the present invention will be described below with reference to the accompanying drawings. Note that components that are substantially the same as those of the prior art are assigned the same reference numerals, and descriptions thereof are omitted.
[0023]
FIG. 1 is an overall view showing an arrangement state of a bridge damping structure according to the present embodiment. As can be seen from the figure, the bridge damping structure 1 according to the present embodiment includes an abutment 3 and a pier 4 which are lower structures of the bridge, and an upper portion supported by a movable support 6 installed on the abutment and the pier. Brake dampers 5 are installed between the bridge girder 2 and the structure.
[0024]
The movable support 6 transmits the vertical load from the bridge girder 2 to the abutment 3 or the pier 4 while allowing the relative horizontal movement of the bridge girder 2 with respect to the abutment 3 or the pier 4 within a predetermined range. Bearings, roller bearings, etc. can be adopted.
[0025]
FIG. 2 shows the brake damper 5 and its mounting state. As can be seen from the figure, the brake damper 5 is pin-joined to the abutment 3 so as to be rotatable around the vertical axis at the abutment side end portion at one end thereof, and also at the other end of the bridge girder side end portion. It is pin-joined to the bridge girder 2 via a height adjustment base 12 so as to be rotatable about a vertical axis. Fig. 2 (b) shows the state of installation of the brake damper 5 on the abutment side, but the brake damper 5 is also installed on the pier in the same way as on the abutment side, except that it is installed symmetrically. It is installed.
[0026]
As shown in FIG. 3, the brake damper 5 includes an intermediate connecting plate 21, a pair of side connecting plates 22 and 22, and a connecting mechanism 23 that connects the intermediate connecting plate 21 and the pair of side connecting plates 22 and 22. It is configured.
[0027]
The intermediate connecting plate 21 is a rod-shaped flat plate having both ends of a connecting end connected to the side connecting plates 22 and 22 and a non-connecting end that is pin-joined to the mounting bracket 25. 24, and friction materials 27 and 27 are provided on both sides of the long hole in parallel with the long hole and over the same length as the long hole 24. The friction materials 27 and 27 are provided on both surfaces of the intermediate connecting plate 21.
[0028]
On the other hand, the side connecting plates 22 and 22 are rod-shaped flat plates having a connecting end connected to the intermediate connecting plate 21 and a non-connecting end pin-connected to the mounting bracket 26 at both ends. Shaped stainless steel plates 28 are respectively attached.
[0029]
Here, the mounting bracket 25 is fixed to the lower surface of the bridge girder 2 via the height adjustment pedestal 12, and the mounting bracket 26 is fixed to the upper surface of the abutment 3 or the pier 4. The mounting bracket 26 is attached to the height adjusting pedestal 12, the abutment 3 or the pier 4 via a spring washer 29 as a vertical displacement absorbing means, and the bridge girder 2 and the abutment 3 or the pier 4 are attached by the spring washer. The relative vertical displacement between them can be absorbed.
[0030]
Two connection mechanisms 23 are arranged along the material axes so that they do not rotate at the connection points between the intermediate connection plate 21 and the side connection plates 22 and 22, as shown in FIG. As can be clearly understood from the exploded view of FIG. 2, the bolt 32 is inserted into the bolt hole 35 drilled in one of the pair of side connecting plates 22 and 22 through the flat washer 33 and the disc spring 34. At the same time, the bolt is inserted into the long hole 24 formed in the intermediate connecting plate 21, and then penetrated into the bolt hole 36 and the flat washer 37 drilled in the other side connecting plate 22, and a nut 38 is provided at the tip thereof. The intermediate connecting plate 21 and the side connecting plates 22 and 22 can be fastened by screwing together, and the intermediate connecting plate 21 and the side connecting plates 22 and 22 are sandwiched between the side connecting plates. Along the stainless steel Scan plate 28 is adapted to be slidable along the upper friction member 27 in Zaijiku direction.
[0031]
The long hole 24 and the friction material 27 ensure a length equal to or greater than the relative horizontal displacement between the bridge girder 2 and the abutment 3 or the pier 4 caused by the horizontal ground motion, and the scale of the horizontal ground motion is required in design. Determined by design seismic motion.
[0032]
In the bridge damping structure 1 according to the present embodiment, the connecting mechanism 23 is provided with a disc spring 34 in a bolt hole 35 drilled in one of the pair of side connecting plates 22, 22. The bolt 32 inserted through the hole is inserted into a long hole 24 formed in the intermediate connecting plate 21, and is passed through a bolt hole 36 drilled in the other side connecting plate 22, and a nut 38 is screwed into the tip. It is configured so that it can be fastened.
[0033]
Therefore, the dynamic friction coefficient between the stainless steel plate 28 and the friction material 27 is set to a desired magnitude by the clamping force of the intermediate connecting plate 21 by the pair of side connecting plates 22, 22, that is, the pressing force by the disc spring 34. If the horizontal ground motion is input to the bridge and a relative horizontal displacement occurs between the bridge girder 2 and the abutment 3 or the pier 4, the friction material 27 provided on both surfaces of the intermediate connecting plate 21 is set. And the stainless steel plate 28 provided on each of the pair of side connection plates 22 and 22 generate a frictional force corresponding to the above-described dynamic friction coefficient, which is converted into heat, thereby the bridge girder. 2 vibration is effectively suppressed. The pressing force by the disc spring 34 can be arbitrarily set by appropriately adjusting the fastening torque of the bolt 32 and the nut 38.
[0034]
The magnitude of the dynamic friction coefficient may be set in consideration of the design strength of the brake damper 5 and its stroke length, that is, the length of the long hole 24. That is, if the design yield strength is increased, the dynamic friction coefficient may be increased by increasing the pressing force of the disc spring 34.
[0035]
In this way, a large amount of energy can be absorbed even with a slight relative horizontal displacement. In such a case, the stroke length may be short.
[0036]
On the other hand, when the design strength of the brake damper 5 is increased in this way, the reaction force corresponding to the brake damper 5 acts on the abutment 3 and the pier 4 to generate a larger stress. Must be increased.
[0037]
Therefore, in order to reduce the scale of the abutment 3 and the pier 4 which are substructures, it is desirable to reduce the design strength while increasing the stroke length.
[0038]
The brake damper 5 according to the present embodiment can set the length of the intermediate connecting plate 21 and the side connecting plates 22 and 22 and thus the stroke length to a desired length. It is possible to adopt the latter method that earns power, and in that sense, it can be said to be an optimum damping device for a bridge.
[0039]
When the design proof strength is lowered, it is possible to follow not only the earthquake but also the deformation of the abutment 3 and the pier 4 due to creep, temperature change, and the like.
[0040]
As described above, according to the bridge damping structure 1 according to the present embodiment, the dynamic friction coefficient between the stainless steel plate 28 and the friction material 27 becomes a desired magnitude due to the pressing force of the disc spring 34. With this setting, when an earthquake occurs, the friction material 27 provided on both surfaces of the intermediate connection plate 21 and the stainless plate 28 provided on each of the pair of side connection plates 22 and 22 slide. Thus, a friction force corresponding to the dynamic friction coefficient is generated. Therefore, the vibration of the bridge girder 2 can be effectively suppressed.
[0041]
Also, in the past, the earthquake response of the bridge could not be sufficiently reduced, so the expansion amount of the expansion joint used for the bridge had to be set large, but the bridge control according to the present embodiment was limited. According to the vibration structure 1, since the vibration of the bridge girder 2 can be effectively suppressed as described above, the expansion / contraction amount of the expansion joint can be set small.
[0042]
Therefore, it is possible to prevent the adverse effects of setting the expansion / contraction amount of the expansion joint to a large value, for example, the difficulty of maintenance and management, the structural defects, the noise generated when passing the vehicle, and the high cost. .
[0043]
Further, according to the bridge damping structure 1 according to the present embodiment, the unconnected ends of the intermediate connecting plate 21 and the side connecting plates 22, 22 rotate around the vertical axis around the bridge girder 2 and the abutment 3 or the pier 4 respectively. Since the pins are movably connected, even if horizontal seismic motion acts on the bridge, only the axial force is transmitted to the intermediate connecting plate 21 and the side connecting plates 22, 22. The vibration energy of the bridge girder 2 can be reliably absorbed by sliding with the stainless steel plate 28.
[0044]
Moreover, according to the bridge damping structure 1 according to the present embodiment, the brake damper 5 is configured by connecting the intermediate connecting plate 21 so as to be sandwiched between the pair of side connecting plates 22, 22. 5 can be suppressed.
[0045]
Therefore, it can be installed even when the clearance between the bridge girder 2 and the abutment 3 or the pier 4 is small, and it can be applied to existing bridges as well as newly built bridges for seismic reinforcement. It becomes possible.
[0046]
Further, according to the bridge damping structure 1 according to the present embodiment, the mounting bracket 25 and the mounting bracket 26 are mounted on the height adjusting base 12, the abutment 3, or the pier via the spring washer 29 as a vertical displacement absorbing means. 4, the relative vertical displacement between the bridge girder 2 and the abutment 3 or the pier 4 can be absorbed by the spring washer.
[0047]
For this reason, only the axial force is transmitted to the intermediate connecting plate 21 and the pair of side connecting plates 22, 22, and the above-described energy absorption by sliding between the friction material 27 and the stainless steel plate 28 is more reliably realized. It becomes possible to plan.
[0048]
In the present embodiment, the height adjustment base 12 is used on the bridge girder 2 side. However, when the height of the brake support 5 need not be adjusted, such as when the height of the movable support 6 is low, this is used. It may be omitted and the mounting bracket 25 may be directly fixed to the bridge girder 2.
[0049]
In the present embodiment, the brake dampers 5 are arranged as a single unit parallel to the bridge axis direction, but instead, as shown in FIG. 5, a plurality of brake dampers 5 may be installed so as to be non-parallel to each other. For example, it is conceivable to install two brake dampers 5 and 5 so as to be orthogonal to each other.
[0050]
According to such a configuration, vibration energy can be absorbed not only in the bridge axis direction but also in the vibration of the bridge girder 2 in the direction orthogonal to the bridge axis, so that energy can be absorbed in all directions after all.
[0051]
【The invention's effect】
As described above, according to the bridge damping structure according to the present invention, when an earthquake occurs, the friction material provided on both surfaces of the intermediate connection plate and the stainless plate provided on each of the pair of side connection plates, Slides to generate a frictional force according to the dynamic friction coefficient. For this reason, it is possible to effectively suppress the vibration of the superstructure.
[0052]
In addition, since the unconnected ends of the intermediate connecting plate and the side connecting plate are pin-joined to the upper structure and the lower structure so as to be rotatable around the vertical axis, even if horizontal earthquake motion acts on the bridge, Only the axial force is transmitted to the connecting plate and the side connecting plate, and thus the vibration energy of the bridge girder can be reliably absorbed by the sliding between the friction material and the stainless steel plate.
[0053]
Further, according to the bridge vibration damping structure of the present invention, the brake damper is configured by connecting the intermediate connecting plate so as to be sandwiched between the pair of side connecting plates, thereby suppressing the overall height of the brake damper. Can do. Therefore, it can be installed even when the clearance between the superstructure and the substructure is small, and it can be applied to existing bridges as well as newly built bridges, and seismic reinforcement can be performed. .
[0054]
[Brief description of the drawings]
FIG. 1 is an overall view showing an arrangement state of a bridge damping structure according to the present embodiment.
FIGS. 2A and 2B are diagrams showing a brake damper 5 and its mounting state, where FIG. 2A is a plan view, and FIG. 2B is an arrow view in the direction of the line AA.
FIGS. 3A and 3B are detailed views of the brake damper, where FIG. 3A is a plan view and FIG. 3B is an arrow view in the BB line direction.
4 is an exploded view of the coupling mechanism 23. FIG.
FIG. 5 is a plan view showing a modified example related to the arrangement of the brake damper 5;
[Explanation of symbols]
1 Damping structure of bridge 2 Bridge girder (superstructure)
3 Abutment (lower structure)
4 Pier (lower structure)
5 Brake damper 6 Movable support 21 Intermediate connecting plate 22 Side connecting plate 23 Connecting mechanism 24 Long hole 27 Friction material 28 Stainless steel plate 29 Spring washer (vertical displacement absorbing means)
32 bolt 34 disc spring 35, 36 bolt hole 38 nut

Claims (1)

An intermediate connecting plate in which a long hole is formed in the material axis direction and a friction material is provided on both surfaces along the material axis direction, and a pair of side connecting plates each having a stainless plate attached to one surface, The intermediate connecting plate and the pair of side connecting plates are relatively movable along the material axis direction with the intermediate connecting plate being sandwiched between the pair of side connecting plates, and the stainless steel plate is the friction material. And a bolt hole formed in one of the pair of side connecting plates. The bolt hole has a connecting mechanism that slidably connects the upper side along the material axis direction. A bolt inserted through a disc spring is inserted into the elongated hole formed in the intermediate connecting plate, and is passed through a bolt hole drilled in the other side connecting plate, and a nut is screwed into the tip. Using a brake damper configured to be fastened A bridge damping structure having a vertical axis on one of the upper structure of the bridge and the lower structure that supports the upper structure via a predetermined movable support with the unconnected end of the intermediate connecting plate being one end of the brake damper The joint of the pair of side connecting plates, which is the other end of the brake damper, is joined to the other of the upper structure and the lower structure so as to be rotatable about a vertical axis. In the vibration control structure of the bridge
The two ends of the brake damper are respectively connected to the upper structure and the lower structure via vertical displacement absorbing means, and the two brackets are connected to each other so as to be rotatable about a vertical axis. Damping structure for bridges.

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