JP2009068295A - Elevated structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an elevated structure so constructed that energy absorbing members absorb energy and thus a main structure mainly receives a dead load and a live load, to prevent the destruction of joint parts between the energy absorbing member and the main structure. <P>SOLUTION: The elevated structure comprises the rigid-frame main structure made of reinforced concrete and having a plurality of bridge piers 114, and beams 112 and bridge girders 115 mounted on the bridge piers, the energy absorbing members 130 skewingly extending from the bridge piers and each having one end connected to one bridge pier of the main structure and the other end connected to one of the other bridge pier, the bridge girder and the beam of the main structure, and adapted to be expanded in the longitudinal direction for absorbing energy input from the outside, the joint parts 134 provided at the ends of the energy absorbing members for abutting on or coming close to the main structure, and movement constraining members installed on the main structure for constraining the movement of the joint parts while each coming close to or abutting on one end of the joint part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an elevated structure, and more particularly to an elevated structure suitable for application to a viaduct.

  Viaducts (elevated structures) are used for railways and highways such as the Shinkansen, and many continuous piers, and continuous girder bridges consisting of beams and bridge girders connecting between the piers are often used. . For the viaduct, a reinforced concrete (RC) ramen structure as shown in FIG. 1 is often applied. Hereinafter, this viaduct is referred to as RC ramen viaduct. FIG. 1 is a side view showing a conventional RC ramen viaduct. As shown in FIG. 1, the viaduct 10 includes a bridge pier 14 having a foundation 16 and a pile 18 fixed to the ground, a beam 12 and a bridge girder 15 formed integrally with the pier 14.

  The conventional RC ramen viaduct is designed so that there is no earthquake damage by designing the main structure consisting of piers, beams, and bridge girders to stay within the elastic range during small and medium earthquakes. On the other hand, in the event of a large earthquake, the conventional RC ramen viaduct prevents the collapse of the RC ramen viaduct by plasticizing the robustly designed main structure.

  However, if the RC ramen viaduct is plasticized during a large earthquake, the RC ramen viaduct will cause damage due to cracks in the concrete, peeling or falling off of the cover concrete, and yielding of the reinforcing bars. Therefore, with the conventional RC ramen viaduct, there is a risk that it will be difficult to continue using the RC ramen viaduct after an earthquake, and there is a risk that the repair cost and the repair period will increase.

  In addition, since Japan is an earthquake-prone area, the load at the time of the earthquake is dominant in the conventional RC ramen viaduct seismic design. For this reason, the size of the main structure is determined by the earthquake, and the main structure of the RC ramen viaduct is a very thick and strong member in order to keep the main structure elastic even in the event of a large earthquake. Therefore, the RC ramen viaduct pillar member proportion has a shape in which the aspect ratio of the member may be 1: 4 or less, and shear fracture is likely to occur. In addition, it is not possible to construct an RC ramen viaduct economically with thick members.

  Further, even if the shear failure of the RC rigid frame viaduct is prevented, the bending moment becomes the maximum at the end of a member such as a bridge pier or a bridge girder in the rigid frame RC rigid frame viaduct. Therefore, after plasticization of the end portion of the member has started due to the occurrence of a large earthquake, strain concentrates on the plasticized portion of the end portion as the deformation progresses. Moreover, since the deformed portion brings about rapid amplification of strain, the RC ramen viaduct rebar may be broken.

  FIG. 2 is a graph showing the relationship between horizontal deformation of RC ramen viaduct and horizontal seismic force. In FIG. 2 (b), the vertical axis represents the load and the horizontal axis represents the amount of deformation, and the inside of the curve represents the seismic energy absorption. As shown in FIG. 2B, the seismic energy absorption amount of the RC ramen viaduct is small and shows a behavior with little attenuation. In addition, the RC ramen viaduct has many horizontal deformations.

  The main structure is an important member that should continue to bear the dead load and live load after the earthquake. However, if a large earthquake causes deformation due to shear failure or bending moment as described above and damage to the RC ramen viaduct, it cannot be used during the investigation or repair work. Therefore, since the economic and social impacts are enormous, it is necessary to construct the RC ramen viaduct so that damage caused by the earthquake is reduced as much as possible.

  Then, this invention is made | formed in view of the said problem, The place made into the objective of this invention is that the main structure receives a dead load and a live load mainly, when an energy absorption member absorbs energy. It is an object of the present invention to provide a new and improved elevated structure which has a structure and can prevent the breakage of the joint between the energy absorbing member and the main structure.

  In order to solve the above problems, according to one aspect of the present invention, there is provided a main structure having a rigid frame structure having a plurality of bridge piers, beams and bridge girders erected on the pier, and made of reinforced concrete. One end is connected to one pier of the main structure, and the other end is connected to one of the other piers, bridge girders and beams of the main structure. An energy absorbing member that expands and contracts to absorb energy input from the outside, a joint provided at or near the end of the energy absorbing member, and a joint near or against one end of the joint. There is provided an elevated structure including a movement restraining member installed in a main structure that comes into contact with and restrains movement of a joint portion.

  With such a configuration, the main structure has a plurality of bridge piers and beams and bridge girders built on the pier, and is a rigid frame structure made of reinforced concrete, and the energy absorbing member extends so as to be inclined with respect to the pier. One end is connected to one pier of the main structure, and the other end is connected to one of the other piers, bridge girders and beams of the main structure, and expands and contracts in the longitudinal direction from the outside. Absorbs the input energy, the joint is provided at the end of the energy absorbing member, and abuts or approaches the main structure, and the movement restraining member approaches or abuts one end of the joint. It is installed in the main structure. The energy absorbing member is, for example, a damper. The energy input from the outside is, for example, earthquake energy.

  The joint is installed at a corner formed by one surface of a pier and one surface of a beam or a bridge girder, one end of the joint is close to or abuts the movement restraining member, and the other end of the joint is on the main structure. The movement of the joint portion may be restrained by approaching or abutting.

  The above-mentioned pier has a foundation projecting in a substantially horizontal direction at the bottom, and the joint portion is installed at a corner formed by one surface of the pier and one surface of the foundation, and one end portion of the joint portion is close to or against the movement restraining member. The other end portion of the joint portion may be in contact with or in contact with the main structure to restrain movement of the joint portion.

  The joint may be installed on one surface of a beam or a bridge girder, and opposite ends of the joint may be close to or abut on the movement restraining member to restrain the movement of the joint.

  The joint portion may be at least partially fixed to the main structure.

  The energy absorbing member may be a damper member in which a maximum value of a possible axial force is limited.

  The proof stress of the movement restraining member may be larger than the maximum axial force that can occur in the energy absorbing member.

  The energy absorbing member may be an elastic-plastic hysteresis damper, an oil damper, a viscoelastic damper, or a friction damper.

  The energy absorbing member may be arranged in a direction orthogonal to the bridge axis direction. The energy absorbing member may be arranged in a direction parallel to the bridge axis direction.

  The lower portions of the plurality of adjacent piers may not be connected but may be separated from each other.

  When the earthquake occurs, the energy absorbing member may absorb the seismic energy, and the seismic load received by the main structure may be reduced as compared with the case where the energy absorbing member is not installed.

  When the earthquake occurs, the main body structure may be adjusted so as to be deformed within the elastic deformation range by the energy absorbing member absorbing the seismic energy.

  According to the present invention, when the energy absorbing member absorbs energy, the main structure is configured to mainly receive a dead load or a live load, and the destruction of the joint between the energy absorbing member and the main structure is prevented. Can do.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

(First embodiment)
First, the viaduct 100 according to the first embodiment of the present invention will be described. FIG. 3 is a cross-sectional view taken along a plane orthogonal to the bridge axis direction showing the viaduct according to the present embodiment.

  The viaduct 100 according to the present embodiment is an example of an elevated structure, and is applied to railways, highways, and the like. The viaduct 100 is, for example, a continuous girder bridge including a plurality of bridge piers 114 that are erected continuously, and a beam 112 and a bridge girder 115 that connect the piers 114. The viaduct 100 is provided with a damping member 130 and can absorb external force such as seismic energy.

  The pier 114, the beam 112, and the bridge girder 115 mainly bear a dead load and a live load applied to the viaduct 100. Hereinafter, the pier 114, the beam 112, and the bridge girder 115 are collectively referred to as a main structure. The main structure of the viaduct 100 is a rigid frame structure made of reinforced concrete (RC) and is integrally formed. Since the viaduct 100 of the present embodiment is provided with the vibration damping member 130, it is possible to reduce the seismic force and the amount of energy absorbed by the main structure.

  The bridge piers 114 are erected as a pair (two spans are one span) in a direction orthogonal to the bridge axis direction. In the viaduct 100, a plurality of pairs of piers 114 are continuously provided in the bridge axis direction.

  The upper part of the bridge pier 114 is connected to the beam 112 and the bridge girder 115, and the lower part of the bridge pier 114 is connected to a foundation 116 formed to project substantially horizontally. The foundation 116 is fixed to the ground, and for example, a direct foundation such as a footing foundation or a pile foundation provided with a pile 118 as shown in FIG. 3 can be applied.

  The foundations 116 of the pair of bridge piers 114 erected in a direction perpendicular to the bridge axis direction may be separated from each other as shown in FIG. 3, or may be connected although not shown. When the foundations 116 are separated from each other, the cross section in the direction perpendicular to the bridge axis direction of the main structure of the viaduct 100 is configured to be open on the lower side as shown in FIG. On the other hand, when the foundations are connected to each other, the cross section in the direction perpendicular to the bridge axis direction of the main structure of the viaduct 100 has a closed configuration.

  The beam 112 is provided on the upper part of a pair of bridge piers 114 standing in a direction perpendicular to the bridge axis direction. Moreover, the bridge girder 115 is provided on the upper part of the bridge pier 114 which stood continuously in the bridge axis direction.

  The floor slab 120 is extended on the upper surface of the beam 112 and the bridge girder 115 as the superstructure of the viaduct 100 in the bridge axis direction. For example, tracks and roads are provided on the upper surface of the floor slab 120.

  The damping member 130 is an example of an energy absorbing member, and is, for example, a linear member that can expand and contract in the long axis direction. A damper member capable of absorbing seismic energy when seismic energy is input to the viaduct 100 can be applied to the damping member 130. The damping member 130 has a property of absorbing seismic energy from a small deformation, and for example, an elastic-plastic hysteresis damper, an oil damper, a viscoelastic damper, a friction damper, or the like can be applied. When the viaduct 100 vibrates, the damping member 130 absorbs the seismic energy input to the viaduct 100 by causing the compression force and the tensile force to act alternately.

  The damping member 130 extends so as to be inclined with respect to the pier 114 as shown in FIG. One end of the damping member 130 is installed at a corner portion formed by the side surfaces of the pier 114 and the foundation 116, and the other end is installed at a corner portion formed by the side surfaces of the pier 114 and the beam 112. Two damping members 130 may be installed crossing each other as shown in FIG. At this time, the two damping members 130 are arranged orthogonal to the bridge axis direction. Depending on the design of the viaduct 100, the damping member 130 can be provided on any one pair of bridge piers 114 among a plurality of bridge piers 114 that are continuously provided in the bridge axis direction.

  When the damping member 130 is, for example, an elastoplastic hysteresis damper, a friction damper, or the like, and the maximum value (upper limit) of the axial force that can occur is clear, the damping member 130 is combined with a joining structure described later. In addition, it is possible to prevent the joint portion between the damping member 130 and the main structure from being destroyed by an unexpected large earthquake.

  Next, with reference to FIG. 4, the joint part of the damping member 130 and the main structure will be described. FIG. 4 is a side view showing a joint portion at a corner constituted by the side surface of the pier and the upper surface of the foundation according to the present embodiment.

  The joint structure at the corner where the bridge pier 114 and the foundation 116 intersect includes a joint 134 and a movement restraining member 144, and the joint 134 has a structure in which movement is restrained by the movement restraining member 144. For example, a technique disclosed in Japanese Patent Application Laid-Open No. 2006-177135 can be applied to the bonding structure.

  The joining portion 134 is connected to each of the first joining plate 136 joined to the side surface of the pier 114, the second joining plate 137 placed on the foundation 116, and the first joining plate 136 and the second joining plate 137. The gusset plate 138 is welded in an orthogonal direction. A damping member 130 is connected to the gusset plate 138 via a splice plate 132 by a connecting bolt.

  The first bonding plate 136 and the second bonding plate 137 of the bonding portion 134 are merely placed on the side surface of the pier 114 or the upper surface of the foundation 116, and are not fixed with an adhesive or the like.

  The movement restraining member 144 is made of, for example, a rectangular steel plate having a predetermined thickness and size (area). The movement restraining member 144 is fixed to the side surface of the bridge pier 114 or the upper surface of the foundation 116 in proximity to or in contact with the distal end portion of the first joining plate 136 or the second joining plate 137. The movement restraining member 144 is fixed to the pier 114 or the foundation 116 with an adhesive 145 such as an epoxy resin adhesive. In order to receive the horizontal force which acts on the front-end | tip part of the 1st joining plate 136 or the 2nd joining plate 137 in the edge part 146 of the movement restraining member 144, the end surface of the 1st joining plate 136 or the 2nd joining plate 137 and the movement restraining member 144 They are preferably installed at the same level. However, since the height is different by the thickness of the adhesive 145, a spacer 147 made of a metal plate is preferably fixed to the lower surface of the end 146 of the movement restraining member 144 as shown.

  Accordingly, a vertical force and a horizontal force act on the first joining plate 136 and the second joining plate 137 of the joining portion 134 due to the tensile force acting on the damping member 130 when the earthquake occurs. The normal force is received by the movement restraining member 144 and received by the pier 114 via the first joining plate 136. On the other hand, the horizontal force is received by the movement restraining member 144 and received by the foundation 116 via the first joining plate 136. As described above, the bonding structure of the present embodiment is controlled by applying a shearing force to the two plates (first bonding plate 136 and second bonding plate 137) fixed by the adhesive 145 such as an epoxy dendritic adhesive. It has a mechanism that resists the pulling force of the vibrating member 130 with the resultant force of two reaction forces.

  The post-installed anchor 149 is driven on the pier 114 or the foundation 116, passes through the spacer 147, protrudes from the upper surface of the tip 146 of the movement restraining member 144, and is fixed by the nut 148. The post-installed anchor 149 has a moment at the tip of the first joint plate 136 or the second joint plate 137 when a vertical force acts on the first joint plate 136 or when a horizontal force acts on the second joint plate 137. The upward force at the time of acting can be suppressed, and the trouble that the tip 146 of the movement restraining member 144 is turned up can be reliably prevented.

  The post-installed anchor 149 is a chemical anchor, a mechanical anchor, or the like. When the post-installed anchor 149 is a chemical anchor, a hole is drilled in the pier 114 or the foundation 116, and a capsule containing, for example, a two-component mixed fixability liquid is accommodated in the hole, and a bolt is inserted into the capsule. The two liquids are mixed and solidified, and the bolt is fixed to the pier 114 or the foundation 116. When the post-installed anchor 149 is a mechanical anchor, the tip is expanded with a bolt and fixed to the pier 114 or the foundation 116. The post-construction anchor 149 and the nut 148 are not necessarily provided, and the joining structure may be a structure without the post-construction anchor 149 and the nut 148. At this time, when the main structure is an existing structure and the damping member 130 is newly installed, the joining structure of the present embodiment does not need to scrape the existing structure or open a hole. There is no noise or vibration.

  The stiffening rib 150 is provided on the upper surface near the tip 146 of the movement restraining member 144. The stiffening rib 150 prevents the distal end 146 of the movement restraining member 144 from bending locally due to an upward force acting on the distal end 146 of the movement restraining member 144. The height, width, and number of the stiffening ribs 150 are set to ensure rigidity. The stiffening rib 150 is not necessarily provided, and the joining structure may be a structure without the stiffening rib 150.

  According to the joint portion 134 of the present embodiment, the vertical force or the horizontal force applied to the joint portion 134 by the tensile force of the damping member 130 can be received by the bridge pier 114 or the foundation 116, and the shear force of the adhesive 145 can be received. Can do. Therefore, the local tensile force does not act on the concrete like the conventional joint structure on the pier 114 or the foundation 116, and the problem that the pier 114 or the foundation 116 is damaged can be solved.

  Furthermore, although a compression force may act on the damping member 130, the first joining plate 136 or the second joining plate 137 of the joining portion 134 is an end portion on the opposite side to the side where the movement restraining member 144 is disposed. In contact with the pier 114 or the foundation 116. Therefore, when the damping member 130 receives a compressive force, the force acting on the joint 134 can be transmitted to the bridge pier 114 or the foundation 116 as a supporting pressure.

  When the above-described joint structure is applied to a general brace material instead of the vibration damping member 130 having the energy absorption performance as in the present embodiment, when the seismic energy is input, the brace material has a compressive force. Causes buckling, and for example, deforms into a "<" shape. Further, even if a tensile force is applied to the buckled brace material, it does not return to a linear shape as in the original shape, and a bent deformation remains. Therefore, when an external force is continuously input as in an earthquake, a bending moment due to P-Δ acts on both ends of the brace material, and an eccentric force acts on the movement restraining member 144 of the joint structure. And since the shear stress applied to each of the movement restricting member 144 and the main structure is not uniform, the shear strength (for example, adhesion strength) of the movement restricting member 144 is lowered.

  On the other hand, when the joining structure is applied to the damping member 130 as in the present embodiment, the damping member 130 has an energy absorption performance that prevents buckling, and thus the joining structure by bending deformation of the end portion of the member as described above. The eccentric load does not act. Therefore, according to the present embodiment, it is possible to prevent the joint structure from being destroyed when an earthquake occurs.

  Further, when the damping member 130 is, for example, an elastoplastic hysteresis damper, a friction damper, or the like, and the maximum value (upper limit) of the axial force calculated assuming the maximum possible earthquake is clear, the damping member 130 is When the vibration member 130 and the bonding structure of the present embodiment are combined, even if a large earthquake occurs, the axial force generated in the vibration damping member 130 is limited, so that the bonding structure of the present embodiment is not destroyed. The yield strength of the structure can be determined. That is, since there is a limit to the force generated at the end of the damping member 130 for any level of earthquake, the joint structure of this embodiment can absorb the seismic energy indefinitely without breaking. It becomes like this.

  For example, when an elastoplastic hysteresis damper is applied as the damping member 130, the horizontal proof stress of the joint structure, in particular the movement restraining member 144, is greater than the maximum axial force of the elastoplastic hysteresis damper (the limit proof strength that can be held to the maximum). It is good to set so that it becomes. Even if the input energy approaches the maximum axial force, the elastic-plastic history damper can continue to hold the axial force due to its performance. On the other hand, when the horizontal strength of the joint structure reaches the maximum strength, brittle fracture occurs. Therefore, in order to prevent the joint structure from reaching the maximum proof stress, the horizontal proof stress of the joint structure, particularly the movement restraining member 144, is set to be larger than the maximum axial force (maximum proof stress that can be held to the maximum) of the elastic-plastic hysteresis damper. As a result, destruction of the joint structure can be prevented.

  In the above description, the joint portion 134 at the corner portion constituted by the side surface of the pier 114 and the upper surface of the foundation 116 has been described. However, the joint portion 134 is formed at the corner portion constituted by the side surface of the pier 114 and the lower surface of the beam 112. The same applies to the case where it is provided, or the case where it is provided at the corner composed of the side surface of the pier 114 and the lower surface of the bridge girder 115.

  As described above, according to the present embodiment, as shown in FIG. 5A, the viaduct 100 of the present embodiment has characteristics that combine the deformation characteristics of the vibration damping member 130 and the deformation characteristics of the main structure. ing. In addition, since the viaduct 100 of the present embodiment uses the characteristics of the damping member 130, the amount of seismic energy absorbed is large as shown in FIG. 5B, and as a result, horizontal deformation can be reduced. FIG. 5 is a graph showing the relationship between horizontal deformation and horizontal seismic force of the viaduct 100 according to this embodiment.

  This embodiment can reduce the earthquake response acceleration and the earthquake response displacement of the viaduct 100 when the damping member 130 absorbs the earthquake energy. As a result, the main structure of the viaduct 100 is adjusted to be deformed within the elastic deformation range when an earthquake occurs, and the main structure can be kept cracked even after the earthquake occurs. Therefore, the viaduct 100 of this embodiment can significantly reduce the earthquake damage of the main structure.

  Moreover, since the damping member 130 can absorb the seismic energy and reduce the seismic response acceleration and seismic response displacement of the viaduct 100, the seismic force and energy absorption received by the main structure can be greatly reduced. . Therefore, members such as the pier 114 and the beam 112 of the main structure can be made thin. Therefore, the viaduct 100 according to the present embodiment can be economically constructed, and shear breakage is less likely to occur because the bridge pier 114 as a pillar is thin.

  Further, since the main structure member is thin, the elastic deformation range is larger than that of the RC rigid frame viaduct where the damping member 130 is not installed, and the viaduct 100 of the present embodiment has an effect of delaying plasticization of the main structure. . In addition, since the main structure member is thin, the rigidity and proof stress of the main structure are reduced, so that the seismic load received by the main structure is reduced. As a result, the earthquake energy can be concentrated on the damping member 130 when an earthquake occurs. Therefore, the function can be separated between the main structure and the damping member 130. That is, the main structure has a cross section that is safe against dead loads or live loads, and the vibration damping member has a size that is safe against earthquake energy, so that the division of roles can be clarified.

  In addition, after the earthquake occurs, the damping member 130 remains deformed and residual deformation occurs, and even if the viaduct 100 remains inclined, the main structure is not damaged by the earthquake, so Residual deformation can be eliminated by removing the damping member 130 from the joint portion 134 by utilizing a restoring force (an effect of returning elasticity). Therefore, according to this embodiment, it is possible to restore the viaduct 100 having the original structural performance by installing the damping member 130 again.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  In the above-described embodiment, the case where the damping member 130 is installed in the direction orthogonal to the bridge axis direction has been described, but the present invention is not limited to such an example. For example, as shown in FIG. 6, the damping member 130 may be disposed in a direction parallel to the bridge axis direction. FIG. 6 is a cross section cut along a plane parallel to the bridge axis direction showing a modified example of the viaduct according to the present embodiment. At this time, the damping member 130 is joined to the main structure at a corner portion constituted by the pier 114 and the foundation 116 and at a corner portion constituted by the pier 114 and the bridge girder 115. In addition, in FIG. 6, the example in which the 2nd joining plate 162 of the junction part 134 is joined to the foundation | substrate 116 with the post-installation anchors 160, such as a chemical anchor, is shown.

  Further, in the embodiment shown in FIG. 3 and the modification shown in FIG. 6, the damping member 130 is a corner constituted by the pier 114 and the foundation 116, a corner constituted by the pier 114 and the beam 112, or the pier 114 Although an example in which the main structure is joined at the corner portion constituted by the bridge girder 115 is shown, the present invention is not limited to such an example. For example, as shown in FIG. 7, one end of the damping member 130 may be joined to the bridge girder 115 at an intermediate portion of the bridge girder 115. At this time, the vibration damping member 130 is joined to the bridge girder 115 by a joint portion including the joining plate 336 and the movement restraining member 344. FIG. 7 is a cross-section cut along a plane parallel to the bridge axis direction showing a modified example of the viaduct according to the present embodiment. Although not shown, when the damping member 130 is disposed in a direction orthogonal to the bridge axis direction, one end of the damping member 130 may be joined to the beam 112 at an intermediate portion of the beam 112.

  In the modification example described with reference to FIGS. 6 and 7, the example in which the damping member 130 is installed on all the structural surfaces surrounded and formed by the one bridge girder 115 and the two bridge piers 114 is described. The present invention is not limited to this example. For example, the viaduct may include both a structural surface where the damping member 130 is installed and a structural surface where the damping member 130 is not installed.

It is a side view which shows the conventional RC ramen viaduct. It is a graph which shows the relationship between horizontal deformation and horizontal seismic force of the conventional RC ramen viaduct. It is sectional drawing cut | disconnected by the surface orthogonal to the bridge-axis direction which shows the viaduct concerning the 1st Embodiment of this invention. It is a side view which shows the junction part in the corner comprised from the side surface of the bridge pier of the same embodiment, and the upper surface of a foundation. It is a graph which shows the relationship between the horizontal deformation of a viaduct and horizontal seismic force which concerns on the same embodiment. It is the cross section cut | disconnected by the surface parallel to the bridge-axis direction which shows the example of a change of the viaduct concerning the embodiment. It is the cross section cut | disconnected by the surface parallel to the bridge-axis direction which shows the example of a change of the viaduct concerning the embodiment.

Explanation of symbols

100 viaduct 112 beam 114 bridge pier 115 bridge girder 116 foundation 118 pile 120 floor slab 130 damping member 132 splice plate 134 joint 136 first joint plate 137 second joint plate 144 movement restraining member 150 stiffening rib

Claims (13)

A main structure of a ramen structure having a plurality of bridge piers and beams and bridge girders constructed on the pier, and made of reinforced concrete;
Extending obliquely with respect to the pier, one end is connected to the pier of one of the main structures, and the other end is the other pier of the main structure, the bridge girder And an energy absorbing member that is connected to any of the beams and absorbs energy input from outside by expanding and contracting in the longitudinal direction;
A joint provided at an end of the energy absorbing member, in contact with or close to the main structure;
A movement restraining member installed in the main structure that restrains the movement of the joining portion in proximity to or in contact with one end of the joining portion;
An elevated structure characterized by comprising: The joint is installed at a corner formed by one surface of the pier and one surface of the beam or the bridge girder,
One end portion of the joint portion is close to or abuts on the movement restraining member, and the other end portion of the joint portion is close to or abuts on the main structure to restrain the movement of the joint portion. The elevated structure according to claim 1. The pier has a foundation projecting in a substantially horizontal direction at the bottom,
The joint is installed at a corner constituted by one surface of the pier and one surface of the foundation,
One end portion of the joint portion is close to or abuts on the movement restraining member, and the other end portion of the joint portion is close to or abuts on the main structure to restrain the movement of the joint portion. The elevated structure according to claim 1 or 2. The joint is installed on one side of the beam or the bridge girder,
The elevated structure according to any one of claims 1 to 3, wherein both opposite ends of the joint portion approach or abut against the movement restraining member and restrain the movement of the joint portion. .   The elevated structure according to claim 1, wherein at least a part of the joint is fixed to the main structure.   The elevated structure according to claim 1, wherein the energy absorbing member is a damper member in which a maximum value of a possible axial force is limited.   The elevated structure according to any one of claims 1 to 6, wherein a proof stress of the movement restraining member is larger than a maximum axial force that the energy absorbing member can occur.   The elevated structure according to claim 1, wherein the energy absorbing member is an elastic-plastic hysteresis damper, an oil damper, a viscoelastic damper, or a friction damper.   The elevated structure according to claim 1, wherein the energy absorbing member is disposed in a direction orthogonal to the bridge axis direction.   The elevated structure according to claim 1, wherein the energy absorbing member is disposed in a direction parallel to the bridge axis direction.   The elevated structure according to any one of claims 1 to 10, wherein lower portions of the plurality of adjacent piers are not connected but are separated from each other.   When an earthquake occurs, the energy absorbing member absorbs seismic energy, and the seismic load received by the main structure is reduced compared to a case where the energy absorbing member is not installed. The elevated structure according to any one of claims 1 to 11.   13. The structure according to claim 1, wherein the main structure is adjusted to be deformed within an elastic deformation range when the energy absorbing member absorbs seismic energy when an earthquake occurs. The elevated structure described.

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