JP2020012280A - Vibration isolation structure for rigid-frame viaduct - Google Patents

Abstract

To provide a vibration isolation structure for rigid-frame viaduct that can reduce ground vibration without lowering the seismic performance of the original rigid-frame viaduct.SOLUTION: In the vibration isolation structure for rigid-frame viaduct, upper ends of columns arranged at intervals in a bridge axis direction are connected by vertical beams and slabs extend from the vertical beams in the bridge axis orthogonal direction. Included are a beam supporting diagonal member 2 connected in a state in which a lower end 21 is fixed to a side surface 112 of a column 11 and an upper end 22 allows displacement at least in a bridge axis direction Y with respect to a lower surface 121 of a vertical beam 12, and a slab supporting diagonal member 4 connected in a state in which a lower end 41 is fixed to a side surface 122 of the vertical beam and an upper end 42 allows displacement at least in a bridge axis orthogonal direction X with respect to a lower surface 14a of a slab 14.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vibration damping structure of a rigid-frame viaduct.

  As disclosed in Patent Literatures 1 and 2, highly crosslinked ramen structures (hereinafter, referred to as “ramen highly crosslinked”) are known. The ramen viaduct has a structure of a ramen frame in which the upper ends of pillars arranged at intervals in the bridge axis direction are connected by vertical beams.

  Patent Literature 1 discloses reducing an impact force generated by a sudden transfer of a vehicle load of a passing train or the like and a vibration generated by resonance excited by a natural frequency of a cantilever between adjacent viaducts. Measures are disclosed. For example, as a countermeasure against vibration in a cantilever of a viaduct, an anti-vibration structure in which an X-type or portal-type reinforcement is arranged to support the cantilever from below is described.

  On the other hand, Patent Literature 2 discloses a seismic retrofit structure in which a brace is arranged on the surface of a ramen frame to improve seismic resistance during an earthquake. Here, a damper brace in which a hysteresis damper is interposed between the beam and the brace body is used for the brace.

JP 2005-282079 A JP 2008-223325 A

  However, there is a case where it is desired to suppress only the ground vibration which increases as a train or the like runs at a high speed with respect to the existing ramen viaduct, not to enhance the earthquake resistance. Ground vibration is dominated by vibration of about 3 Hz to 10 Hz, so a structure that can efficiently reduce the frequency band of 10 Hz or less is required.

  However, if renovation is performed to increase rigidity by adding more columns between the columns of the ramen viaduct, the shear span ratio of the longitudinal beams and columns will be shortened, and the damage position and fracture mode of the members expected in the design will be reduced. It can change from bending failure to shear failure. For this reason, as a method for reducing the vibration of the member by taking measures against the ground vibration, a simple method of adding the member is not preferable in consideration of the influence on the seismic performance.

  Therefore, an object of the present invention is to provide a vibration isolation structure of a rigid-frame viaduct that can reduce ground vibration without lowering the seismic performance of the original rigid-frame viaduct.

  In order to achieve the above object, the vibration damping structure for a rigid-frame viaduct of the present invention has a structure in which the upper ends of columns arranged at intervals in the bridge axis direction are connected by vertical beams, and the vertical beams are orthogonal to the bridge axis. A vibration damping structure of a rigid-frame viaduct having a slab extending in a direction, wherein a lower end is fixed to a side surface of the column, and an upper end is displaced at least in the bridge axis direction with respect to a lower surface of the vertical beam. A beam receiving member connected in an allowed state, and a lower end fixed to a side surface of the longitudinal beam, and an upper end connected to a lower surface of the slab at least in a direction perpendicular to the bridge axis; And a slab receiving material to be used.

  Here, in the portal space formed by the pair of columns and the vertical beams facing each other in the bridge axis direction, the beam receiving members whose lower ends are fixed to the side surfaces of the respective columns are paired. The upper end of the pair of beam oblique members is joined to a top jig connected to the lower surface of the longitudinal beam at least in a state of allowing displacement in the bridge axis direction. Configuration. Further, the upper end of the slab receiving member may be configured to be joined to a long piece jig connected to the lower surface of the slab at least in a state of allowing displacement in a direction orthogonal to the bridge axis. .

The anti-vibration structure of the ramen viaduct of the present invention configured as described above has a structure in which the beam receiving members supporting the vertical beams are installed in a state where displacement in the bridge axis direction is allowed, and the beams are projected from the vertical beams in the direction orthogonal to the bridge axis. The slab support members that support the slab to be installed are installed in a state that allows displacement in the direction orthogonal to the bridge axis.
Therefore, the occurrence of ground vibration can be reduced without lowering the original seismic performance of the ramen viaduct.

  Installation of such beam and slab support members can be easily performed by interposing a top jig or a long piece jig that is connected while allowing displacement in the bridge axis direction or in the direction orthogonal to the bridge axis. Can be implemented.

It is a perspective view for explaining the composition of the vibration isolation structure of the ramen viaduct of this embodiment. It is a perspective view for demonstrating the structure of the existing ramen viaduct. It is the perspective view which showed the analysis model of ramen viaduct. The figure which showed the analysis result by the analysis model of the ramen viaduct in the middle part of the slab, (a) is the figure which showed the primary result of the vibration mode, (b) is the figure which showed the secondary result of the vibration mode It is. FIGS. 7A and 7B are diagrams showing an analysis result by an analysis model of a ramen viaduct in an overhang portion of a slab, in which FIG. 7A shows a first order vibration mode result, and FIG. 7B shows a second order vibration mode result. FIG. 3C is a diagram showing the result of the fourth order vibration mode. FIGS. 6A and 6B are diagrams showing the results of confirming, by numerical analysis, the effect of reducing the ground vibration when the rigidity of each member is increased. FIG. 6A is a diagram showing the results of an intermediate portion of the slab, and FIG. FIG. 7C is a diagram showing a result of a vertical beam, and FIG. 7C is a diagram showing a result of a vertical beam. It is a perspective view for explaining the state where various jigs were attached to the ramen viaduct. It is a perspective view for explaining the composition of the pillar side jig attached to the side of a pillar. It is a side view for demonstrating the structure of the top part jig attached to the lower surface of a vertical beam. It is a perspective view for explaining the composition of the lower end jig attached to the side of a longitudinal beam. It is a figure for demonstrating the structure of the long piece jig attached to the lower surface of a slab, (a) is a side view, (b) is a top view. It is a perspective view for explaining the state where the beam receiving member and the top jig were attached to the ramen viaduct. It is a perspective view for demonstrating the state which attached the beam receiving member and the slab receiving member to the ramen viaduct.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining the configuration of the vibration isolating structure of the ramen viaduct 1 of the present embodiment, and FIG. 2 is a perspective view for explaining the configuration of the existing ramen viaduct 1.

  First, the ramen viaduct 1 will be described with reference to FIG. This ramen viaduct 1 is constructed of a reinforced concrete or a prestressed concrete into a structure having a structure of a ramen frame.

  Specifically, columns 11, ... arranged at intervals in the bridge axis direction Y, vertical beams 12 connecting the upper ends 111, 111 of the columns 11, 11 in the bridge axis direction Y, and columns It mainly comprises a cross beam 13 connecting the upper ends 111 of the 11, 11 in the direction X orthogonal to the bridge axis, and a slab 14 provided above the vertical beam 12 and the cross beam 13.

  The column 11 is formed in, for example, a rectangular parallelepiped shape, and a corner portion rigidly connected to the rectangular parallelepiped vertical beam 12 is constructed. In other words, the pillar-shaped rigid frame is formed by the columns 11, 11 and the vertical beams 12 arranged at intervals in the bridge axis direction Y.

  In addition, the column 11 is also rigidly connected to a rectangular cross beam 13 extending in the direction X orthogonal to the bridge axis. That is, the portal-shaped rigid frame is also formed by the columns 11, 11 and the cross beams 13 arranged at intervals in the direction X orthogonal to the bridge axis.

  Further, the slab 14 covers the upper surface surrounded by the vertical beams 12, 12 and the horizontal beams 13, 13 and protrudes outside the vertical beam 12 in a cantilever state. Here, a portion of the slab 14 extending in the bridge axis orthogonal direction X between the vertical beams 12, 12 is defined as an intermediate portion 142, and a portion of the slab 14 extending in the bridge axis orthogonal direction X outside the vertical beam 12 is extended. Let it be the outgoing part 141. A side wall 143 is provided on a side edge of the overhang 141.

  Subsequently, the vibration mode of such a rigid-frame viaduct 1 will be described with reference to numerical analysis results shown in FIGS. FIG. 3 shows an analytical model (M1) of the adjustable girder-type viaduct of three spans. As for the analysis model, a symbol with “M” added before a member with a symbol is used.

  FIG. 4 shows an analysis result by extracting only the middle portion M142 of the slab M14. FIG. 4A shows a first-order result in the vibration mode, and FIG. 4B shows a second-order result in the vibration mode. As can be seen from these results, a clear amplitude (vibration mode) appears in the middle part M142 of the slab M14 with the existing ramen viaduct M1 as it is.

  On the other hand, FIG. 5 shows an analysis result by extracting only the overhang portions M141 and M141 of the slab M14. FIG. 5A shows a first-order result in the vibration mode, FIG. 5B shows a second-order result in the vibration mode, and FIG. 5C shows a fourth-order result in the vibration mode. Is shown. As can be seen from these results, a clear amplitude (vibration mode) appears in the overhangs M141 and M141 of the slab M14 with the existing ramen viaduct M1 as it is. Here, the broken lines of the overhang portion M141 and the side wall portion M143 indicate the state before the vibration, and the solid lines indicate the state during the vibration.

  Next, a description will be given of effective measures for reducing the vibration of the rigid-frame viaduct 1 in which the above-described vibration mode occurs. FIG. 6 shows the results of a numerical analysis comparing with a configuration in which the rigid-frame viaduct 1 having a normal configuration is used as the “basic” and the rigidity of each member is increased to make it less likely to shake. The results of the numerical analysis are arranged with the horizontal axis representing frequency (Hz) and the vertical axis representing vibration acceleration level (dB).

  FIG. 6A shows a comparison between “basic” and “intermediate slab rigidity 100 times” in which the rigidity of the intermediate portion 142 of the slab 14 is increased by 100 times. FIG. 6B shows a comparison between “extension slab rigidity 100 times” in which the rigidity of the overhang portion 141 of the slab 14 is increased 100 times and “basic”. Further, FIG. 6C shows a comparison between “basic beam” and “longitudinal beam rigidity 100 times” in which the rigidity of the longitudinal beam 12 is increased by 100 times.

  From these analysis results, it can be seen that increasing the rigidity and making it harder to shake can reduce the vibration acceleration level in the range of 4 Hz to 20 Hz. In other words, it can be seen that the ground vibration is dominated by the vibration of about 3 Hz to 10 Hz, and the effect of reducing the ground vibration can be obtained by making each member hard to shake.

  Therefore, in the vibration isolation structure of the rigid-frame viaduct 1 of the present embodiment, the beam receiving members 2 that support the vertical beams 12 from below and the slab receiving members 4 that support the slab 14 from below are arranged. In short, a member that is likely to generate a vibration mode is supported from below, so that the structure is modified to be less likely to shake.

  However, if both ends of the beam receiving member 2 and the slab receiving member 4 are rigidly joined to the respective surfaces of the rigid frame viaduct 1, the rigidity of the rigid frame viaduct 1 is partially increased, and the failure mode was assumed at the time of design. It may be different from something.

  More specifically, if the column 11 and the vertical beam 12 or the vertical beam 12 and the lower surface 14a of the slab 14 are rigidly connected by a diagonal member, the shear span ratio of the column 11 and the vertical beam 12 of the rigid frame viaduct 1 will be described. May be shortened, and the damage position and fracture mode assumed in the design may change from bending fracture to shear fracture. Changes in the form of failure may affect seismic resistance, requiring redesign and reinforcement of other parts. Further, the deformation of the member due to the drying shrinkage or the temperature expansion and contraction of the concrete is restrained, which may cause cracking.

  Therefore, in the vibration isolation structure of the rigid-frame viaduct 1 of the present embodiment, the beam receiving member 2 and the slab receiving member 4 are arranged mainly for the purpose of reducing ground vibration, and the intermediate portion 142 of the slab 14 The horizontal behavior of the protrusion 141 and the vertical beam 12 is not restricted, and only the vertical load is resisted.

  More specifically, the lower beam 21 is fixed to the side surface 112 of the column 11, but the upper end 22 is at least allowed to displace in the bridge axis direction Y with respect to the lower surface 121 of the vertical beam 12. Connect. That is, at least the displacement in the direction extending continuously with the axis of the beam receiving member 2 as the axial force member is not restricted. In addition, they can be connected in a state where displacement in the bridge axis orthogonal direction X is also allowed.

  On the other hand, the lower end 41 of the slab receiving member 4 is fixed to the side surface 122 of the vertical beam 12, but the upper end 42 is connected to the lower surface 14 a of the slab 14 at least in a state where displacement in the bridge axis orthogonal direction X is allowed. . That is, at least the displacement in the direction extending continuously with the axis of the slab receiving member 4 as the axial force member is not restricted. In addition, they can be connected in a state where displacement in the bridge axis direction Y is allowed.

  Therefore, a configuration that is an example of the vibration isolation structure of the rigid-frame viaduct 1 of the present embodiment will be described with reference to FIG. The beam receiving member 2 is bridged so as to be bilaterally symmetrical in a portal space formed by a pair of columns 11, 11 and a vertical beam 12 facing each other in the bridge axis direction Y.

  The upper ends 22, 22 of the pair of beam receiving members 2, 2 are joined to the top jig 3 connected to the lower surface 121 of the longitudinal beam 12 while allowing displacement in the bridge axis direction Y. Further, the lower end 21 of the beam receiving member 2 is fixed to the side surface 112 of the column 11 via the column side jig 6 as an end jig. That is, by arranging a mountain-shaped reinforcing device formed by the top jig 3 and the left and right beam receiving members 2 in the portal space, the vibration (sway) of the vertical beam 12 is suppressed.

  On the other hand, the slab receiving material 4 is stretched in the bridge axis orthogonal direction X in plan view. The upper end 42 of the slab receiving member 4 is joined to the long piece jig 5 which is connected to the lower surface 14a of the slab 14 while allowing displacement in the direction X orthogonal to the bridge axis. The lower end 41 of the slab receiving member 4 is fixed to the side surface 122 of the vertical beam 12 via the lower end jig 7 as an end jig.

  FIG. 7 shows a state in which the long piece jig 5 and the lower end jig 7 for the slab oblique material 4 and the column-side jig 6 for the beam oblique material 2 are attached to the rigid frame viaduct 1. FIG. 8 is a perspective view for explaining a configuration of the column-side jig 6 attached to the side surface 112 of the column 11 on the bridge axis direction Y side.

  The column-side jig 6 includes a rectangular plate-shaped base portion 61 to be brought into contact with the side surface 112, a peripheral wall portion 62 provided along each side of the base portion 61, a bolt member 63 and a nut 64 for fixing to the column 11. It is mainly composed of

  The peripheral wall portion 62 is provided in accordance with the inclination angle of the beam receiving member 2, and accommodates the lower end 21 of the beam receiving member 2 and is joined by welding or the like. The column-side jigs 6 are arranged on both side surfaces 112, 112 on both sides of the column 11, and a plurality of bolt members 63,... Penetrate the column 11 so as to connect the opposing base portions 61. Attached. In this way, the column-side jig 6 is a fixed point whose position does not change with respect to the column 11.

  On the other hand, FIG. 9 shows an enlarged view of the periphery of the joint between the top jig 3 and the beam receiving material 2. The top jig 3 mainly includes the main body 31, an upper flange 311 forming an upper surface, and a lower flange 312 forming a lower surface. For example, the top jig 3 can be made of H-section steel or the like.

  Then, the end plate 221 for closing the upper end 22 of the beam receiving member 2 is brought into contact with the lower flange 312 of the top jig 3, and the two are joined by the bolt 23 and the nut 231. On the other hand, the upper flange 311 side of the top jig 3 has a connection structure in which at least displacement in the bridge axis direction Y is allowed with respect to the lower surface 121 of the vertical beam 12.

  More specifically, a sliding member having a lubricating material 35 such as lubricating oil for further reducing the frictional resistance between the smooth surface plates 34A, 34B is interposed between the smooth surface plates 34A, 34B formed of a tetrafluoroethylene resin plate or the like. The structure is interposed between the lower surface 121 of the vertical beam 12 and the upper flange 311.

  The upper sliding plate 34A of this sliding structure is attached to the lower surface 121 of the longitudinal beam 12, and the lower sliding plate 34B is attached to the upper surface of the upper flange 311. That is, the smooth plate 34B and the upper flange 311 are integrated to form a variable plate.

  The top jig 3 is joined to the longitudinal beam 12 by a plurality of anchor members 33,. That is, the tip of the anchor 33 is embedded in the longitudinal beam 12, and the head of the anchor 33 is passed through the elongated hole 32 formed in the upper flange 311.

  The elongated hole 32 has an oval or elliptical shape extending in the bridge axis direction Y, and the head of the anchor member 33 is fixed to the upper flange 311 by the supporting plate 332 and the nut 331 spanned over the elongated hole 32. (See FIG. 11B). Here, a hole of the same size that is projected and overlapped with the elongated hole 32 is also drilled in the smooth surface plate 34B attached to the upper surface of the upper flange 311.

  When the top jig 3 thus joined to the longitudinal beam 12 tries to move in the bridge axis direction Y, a slip occurs between the smooth surface plates 34A and 34B, and the top jig 3 is restrained within the range of the elongated hole 32. The top jig 3 can be moved without the need. In short, the beam receiving member 2 does not reinforce the corner formed by the column 11 and the vertical beam 12, but is a member that simply supports the vertical beam 12 from below.

  FIG. 10 is a perspective view for explaining the configuration of the lower end jig 7 attached to the side surface 122 of the vertical beam 12. The lower end jig 7 includes a rectangular plate-shaped base portion 71 to be brought into contact with the side surface 122, a peripheral wall portion 72 provided along each side of the base portion 71, a bolt member 73 and a nut 74 for fixing to the vertical beam 12. It is mainly composed of

  The peripheral wall portion 72 is provided in accordance with the inclination angle of the slab oblique member 4, and accommodates the lower end 41 of the slab oblique member 4 and is joined by welding or the like. The lower end jig 7 is disposed on both side surfaces 122, 122 sandwiching the vertical beam 12, and a plurality of bolt members 73,... Penetrate the vertical beam 12 so as to connect the opposing base portions 71, 71. Attach it. In this way, the lower end jig 7 is a fixed point whose position does not change with respect to the vertical beam 12.

  On the other hand, FIG. 11 shows an enlarged view of the periphery of the long piece jig 5 attached to the lower surface 14a of the overhang portion 141 of the slab 14. The same long jig 5 is attached to the lower surface 14 a of the intermediate portion 142 of the slab 14. Here, FIG. 11A is a side view of the long piece jig 5, and FIG. 11B is a top view of the long piece jig 5.

  The long piece jig 5 is mainly configured by a rectangular plate-shaped base portion 51 to be brought into contact with the lower surface 14a, and a peripheral wall portion 54 provided along each side of the base portion 51. The long piece jig 5 has a connection structure that allows at least displacement in the bridge axis orthogonal direction X with respect to the lower surface 14 a of the slab 14.

  Specifically, a sliding member having a lubricating material 56 for further reducing the frictional resistance between the smooth surface plates 34A and 34B such as lubricating oil is interposed between the smooth surface plates 55A and 55B formed of a tetrafluoroethylene resin plate or the like. The structure is interposed between the lower surface 14a of the slab 14 and the base 51.

  The upper sliding plate 55A of this sliding structure is attached to the lower surface 14a of the slab 14, and the lower sliding plate 55B is attached to the upper surface of the base 51. That is, the smooth plate 55B and the base portion 51 are integrated to form a variable plate.

  The long piece jig 5 is joined to the slab 14 by a plurality of anchor members 53,. That is, the tip of the anchor member 53 is embedded in the slab 14, and the head of the anchor member 53 is passed through the elongated hole 52 formed in the base portion 51.

  The elongated hole 52 has an oval or elliptical shape extending in the direction X orthogonal to the bridge axis, and the head of the anchor member 53 is fixed to the base portion 51 by the supporting plate 532 and the nut 531 spanned over the elongated hole 52. Is done. Here, holes of the same size that are projected and overlapped with the elongated holes 52 are also drilled in the smooth surface plate 55 </ b> B attached to the upper surface of the base portion 51.

  When the long piece jig 5 thus joined to the slab 14 tries to move in the direction X orthogonal to the bridge axis, slippage occurs between the smooth surface plates 55A and 55B, and is constrained within the range of the long hole 52. The long piece jig 5 can be moved without the need. In short, the slab oblique material 4 does not reinforce the corner formed by the longitudinal beam 12 and the overhang 141 (or the intermediate part 142), but simply places the overhang 141 or the intermediate part 142 from below. It is a member that only supports.

Next, a method of constructing the vibration-proof structure of the rigid-frame viaduct 1 of the present embodiment will be described.
This vibration-proof structure can be provided in both the new ramen viaduct 1 and the existing ramen viaduct 1. In the present embodiment, a case will be described in which an anti-vibration structure is provided for an existing ramen viaduct 1 in order to reduce ground vibration.

  As shown in FIG. 7, the column-side jig 6 is attached to the side surface 112 of the column 11 facing the bridge axis direction Y with respect to the existing ramen viaduct 1 as shown in FIG. 2. The column-side jigs 6 are arranged on the side surfaces 112, 112 on both sides of the column 11, and are fixed to the columns 11 by connecting the column-side jigs 6, 6 on both sides with bolts 63,. I do.

  On the other hand, the lower end jig 7 is attached to the side surface 122 of the vertical beam 12. The lower end jig 7 is arranged at the span center position and the span 1/4 position of the vertical beam 12 bridged between the columns 11, 11 facing in the bridge axis direction Y in accordance with the position where the slab oblique material 4 is arranged. I do.

  The lower end jigs 7 are arranged on the side surfaces 122, 122 on both sides of the vertical beam 12, and the lower end jigs 7, 7 on both sides are connected to each other by bolts 73,. Fix it. In addition, the long piece jig 5 that is paired with the lower end jig 7 is attached to the lower surface 14 a of the overhang portion 141 and the intermediate portion 142.

  Subsequently, as shown in FIG. 12, the top jig 3 and the beam receiving members 2, 2 are arranged in the portal space formed by the columns 11, 11 and the vertical beams 12 facing each other in the bridge axis direction Y. . The position where the top jig 3 is arranged is the center of the longitudinal beam 12 in the bridge axis direction Y, that is, the center between the spans of the columns 11 and 11 facing the bridge axis direction Y.

  The lower end 21 of the beam receiving member 2 is joined to the column-side jig 6 by welding. Further, the top jig 3 is joined to the lower surface 121 of the longitudinal beam 12 by the anchor member 33. Therefore, a plurality of anchor members 33,... Passing through the plurality of elongated holes 32 project toward the inside of the vertical beam 12 above the top jig 3.

  Further, as shown in FIG. 13, the slab oblique members 4 are arranged in the bridge axis direction Y at intervals of １ ／ of the span length between the columns 11, 11. With such an arrangement, the peak of the vibration mode can be suppressed.

  The lower end 41 of the slab receiving member 4 is housed in the peripheral wall 72 of the lower end jig 7 and joined by welding. Further, the upper end 42 of the slab receiving member 4 is accommodated in the peripheral wall portion 54 of the long piece jig 5 and joined by welding. A plurality of anchor members 53,... Passing through the plurality of long holes 52 project above the long piece jig 5 toward the inside of the slab 14.

Next, the operation of the vibration isolating structure of the rigid-frame viaduct 1 of the present embodiment will be described.
The anti-vibration structure of the rigid-frame viaduct 1 according to the present embodiment configured as described above is installed in a state where the beam receiving member 2 supporting the vertical beam 12 is allowed to be displaced in the bridge axis direction Y. The slab receiving member 4 supporting the projecting portion 141 and the intermediate portion 142 of the slab 14 projecting in the bridge axis orthogonal direction X is installed in a state where displacement in the bridge axis orthogonal direction X is allowed.

  For this reason, occurrence of ground vibration can be reduced without lowering the original seismic performance of the existing ramen viaduct 1. In other words, by supporting the vertical beam 12 and the projecting portion 141 and the intermediate portion 142 of the slab 14 projecting therefrom from below so as not to sway, the vibration of 10 Hz or less, which is a frequency band dominant in the vibration level, is reduced. can do. Further, since the beam receiving member 2 and the slab receiving member 4 are installed so as not to restrict the deformation of the member due to the drying shrinkage of the concrete and the expansion and contraction of the temperature, the negative influence of the installation can be minimized.

  If the ground vibrations can be suppressed by such simple reinforcement, studies are being made for speeding up the running speed of a train such as a Shinkansen running on a track laid on the slab 14 of the ramen viaduct 1. Even in such a case, it is possible to make a plan that suppresses an increase in ground vibration along the railway.

  That is, the installation of such a beam receiving member 2 or a slab receiving member 4 is performed by connecting the top jig 3 or the long piece jig which is connected while allowing displacement in the bridge axis direction Y or the bridge axis orthogonal direction X. 5 can be easily implemented.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes that do not depart from the gist of the present invention may be made in the present invention. Included in the invention.
For example, the structure of the rigid-frame viaduct 1 described in the above embodiment is an example, and the present invention is not limited to this. Any form such as an adjustment girder-type rigid-frame viaduct, an overhang-type rigid-frame viaduct, and a beam-slab-type rigid-frame viaduct is possible. The present invention can also be applied to ramen viaducts.

1: ramen viaduct 11: pillar 111: upper end 112: side surface 12: vertical beam 121: lower surface 122: side surface 14: slab 14a: lower surface 141: overhang portion 142: intermediate portion 2: beam receiving member 21: lower end 22: upper end 3: Top jig 32: Long hole 33: Anchor material 34A: Smooth plate 34B: Smooth plate 35: Lubricant 4: Slab oblique material 41: Lower end 42: Upper end 5: Long piece jig 52: Long hole 53: Anchor Material 54: Peripheral wall portion 55A: Smooth surface plate 55B: Smooth surface plate 56: Lubricant 6: Column side jig 62: Peripheral wall portion 63: Bolt material 7: Lower end jig 72: Peripheral wall portion 73: Bolt material X: Bridge axis orthogonal direction Y: Bridge axis direction

Claims (7)

A vibration isolation structure of a rigid-frame viaduct having a slab extending from the vertical beam in a direction orthogonal to the bridge axis, with the upper ends of the columns arranged at intervals in the bridge axis direction being connected by a vertical beam,
A beam receiving member whose lower end is fixed to a side surface of the column and whose upper end is connected to a lower surface of the vertical beam at least in a state of allowing displacement in the bridge axis direction,
A lower end is fixed to a side surface of the vertical beam, and an upper end is provided with a slab receiving member which is connected to a lower surface of the slab at least while allowing displacement in a direction orthogonal to the bridge axis. The anti-vibration structure of the ramen viaduct. In the portal space formed by the pair of pillars and the vertical beams facing each other in the bridge axis direction, the beam receiving members whose lower ends are fixed to the side surfaces of the respective columns are paired. Are located,
The upper end of the pair of beam receiving members is joined to a top jig connected to the lower surface of the longitudinal beam at least in a state of allowing displacement in the bridge axis direction. Item 4. The vibration-damping structure of the ramen viaduct according to Item 1.   The upper end of the slab receiving member is joined to a long piece jig which is connected to the lower surface of the slab at least in a state of allowing displacement in a direction orthogonal to the bridge axis. Or the vibration damping structure of the ramen viaduct according to 2. The top jig includes a smooth plate fixed to the lower surface of the vertical beam, a variable plate to which an upper end of the beam receiving member is joined, and an anchor material penetrating these.
A plurality of elongated holes extending in the bridge axis direction are provided on the variable plate that is superimposed on the smooth surface plate with a small frictional resistance, and the anchor material is passed through the long hole and fixed to the variable plate. The vibration damping structure for a rigid-frame viaduct according to claim 2, wherein The long piece jig includes a smooth plate fixed to the lower surface of the slab, a variable plate to which an upper end of the slab receiving member is joined, and an anchor material penetrating these.
A plurality of elongated holes extending in a direction orthogonal to the bridge axis are provided on the variable plate which is superimposed on the smooth surface plate with a small frictional resistance, and the anchor material is passed through the long hole and is fixed to the variable plate. The vibration damping structure of a rigid-frame viaduct according to claim 3, wherein   Lower ends of the beam oblique members or the slab oblique members are arranged on both sides of the column or the vertical beam, and lower ends of both sides are connected by bolts penetrating the columns or the vertical beams. The vibration damping structure of a rigid-frame viaduct according to any one of claims 1 to 5, characterized in that:   The lower end of the beam receiving member or the slab receiving member is joined to an end jig provided with a peripheral wall portion surrounding the lower end, 7. Anti-vibration structure of ramen viaduct.