Method and apparatus for erecting suspension bridge structures

Abstract

The present invention provides a suspension bridge suspension structure erection method and suspension structure erection device that can reduce the weight of the erection device itself. [Solution] A pair of first suspension members 40, whose upper ends are connected to the end beam portion 21 of the erection device body 20, are arranged on both sides of the main cable 3 perpendicular to the bridge axis. A second suspension member 50, connected to the lower end of each first suspension member 40 and extending perpendicular to the bridge axis, is connected to the suspension structure 5 before erection. The suspension structure 5 is lifted to the erection position by each suspension member 40, 50. As a result, the load of the heavy suspension structure 5 is not applied to the central beam portion 22 of the erection device body 20, and the strength of the central beam portion 22 of the erection device body 20 can be reduced. Furthermore, the second suspension member 50 is moved inward perpendicular to the bridge axis to a position where contact with the hanger cable 4 can be avoided. As a result, each suspension member 40, 50 does not come into contact with the hanger cable 4 and can pass alongside the hanger cable 4 without obstruction.

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for erecting a suspension structure of a suspension bridge for lifting and erecting a suspension structure such as a supplementary stiffening girder in a suspension bridge erected over a river, a strait or the like.

Background Art

[0002] Generally, a suspension bridge erected over a river, a strait or the like is composed of a plurality of main towers arranged at intervals in the bridge axis direction, a main cable spanned between the main towers, a plurality of hanger cables arranged at intervals in the bridge axis direction, and a suspension structure such as a supplementary stiffening girder suspended from the main cable by each hanger cable.

[0003] When erecting such a suspension bridge, after spanning the main cable between the main towers, a plurality of suspension structures divided in the bridge axis direction are transported on water by a pontoon or the like below the main cable, and are lifted to the erection position by an erection apparatus installed on the main cable (see, for example, Patent Documents 1 and 2).

[0004] The erection apparatus includes an erection apparatus main body extending in the direction perpendicular to the bridge axis across the main cables arranged on both end sides in the direction perpendicular to the bridge axis, and is configured to lift the suspension structure by a suspension member suspended from the erection apparatus main body, and is adapted to move in the bridge axis direction by traveling on the main cable to lift other suspension structures.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, in the aforementioned erection device, when moving along the main cable in the bridge axis direction, the suspension members suspended from the erection device body are positioned at a location perpendicular to the bridge axis relative to the main cable so as not to interfere with the hanger cable. As a result, the suspension load of the suspended structure is transmitted to the main cable via the erection device body.

[0007] As a result, in the erection device itself, the loading point, which is the suspension position of the suspended structure, and the reaction support point located on the main cable are separated in a direction perpendicular to the bridge axis. Therefore, a bending moment is generated in the erection device itself due to the suspension load of the suspended structure. For this reason, the bending strength of the erection device itself needs to be increased, but in order to increase the strength, the erection device itself must be made larger, which increases the weight of the erection device itself accordingly.

[0008] In other words, an increase in the weight of the erection device itself affects the required capacity of equipment used for installing and moving the erection device, such as the tower crane used for assembling and disassembling the erection device, and the tower winch used to move the erection device along the main cable. In particular, in suspension bridges where the main cables are spaced far apart, the erection device itself becomes even larger and heavier, which can sometimes limit the equipment capacity for the entire suspension bridge erection project.

[0009] This invention has been made in view of the above-mentioned problems, and its objective is to provide a suspension bridge suspension structure erection method and suspension structure erection device that can reduce the weight of the erection device itself. [Means for solving the problem]

[0010] To achieve the above objective, the present invention provides a method for erecting a suspension structure for a suspension bridge, comprising main cables arranged on both sides perpendicular to the bridge axis of the suspension bridge, a plurality of hanger cables spaced apart from each other in the bridge axis direction, and a suspension structure suspended from the main cables by each hanger cable, wherein the erection device has an erection device body formed to extend perpendicular to the bridge axis across each of the main cables, and is installed on the main cables so as to be movable in the bridge axis direction, and a pair of first suspension members, whose upper ends are connected to the ends of the erection device body perpendicular to the bridge axis, are arranged on both sides perpendicular to the bridge axis of the main cable, and each The suspension structure before erection is connected to a second suspension member, which is connected to the lower end of the first suspension member and extends perpendicular to the bridge axis. The suspension structure is then lifted to the erection position by each suspension member, and after connecting the suspension structure to the hanger cable suspended from the main cable, the connection between the lower end of the first suspension member on the outside perpendicular to the bridge axis and the second suspension member is released. The second suspension member, which is connected to the first suspension member on the inside perpendicular to the bridge axis, is moved inward perpendicular to the bridge axis to a position where contact with the hanger cable can be avoided when moving in the bridge axis direction. The erection device with each suspension member connected is then moved along the main cable to the erection position of the next suspension structure.

[0011] Furthermore, in order to achieve the above objective, the present invention provides a suspension structure erection device for erecting a suspension structure for a suspension bridge, comprising main cables arranged on both sides perpendicular to the bridge axis of the suspension bridge, a plurality of hanger cables spaced apart from each other in the bridge axis direction, and a suspension structure suspended from the main cables by each hanger cable, wherein the erection device body is formed to extend perpendicular to the bridge axis across each of the main cables and is installed on the main cables so as to be movable in the bridge axis direction, and the main cables perpendicular to the bridge axis The device comprises a pair of first suspension members positioned on both sides, with their upper ends connected to the end of the erection device body perpendicular to the bridge axis, and second suspension members connected to the lower ends of each first suspension member and extending perpendicular to the bridge axis, to which the suspension structure before erection is connected. The second suspension member, which is disconnected from the lower end of the first suspension member on the outside perpendicular to the bridge axis and connected to the suspension member on the inside perpendicular to the bridge axis, is configured to be movable perpendicular to the bridge axis to a position where contact with the hanger cable can be avoided during movement in the bridge axis direction.

[0012] As a result, a pair of first suspension members, whose upper ends are connected to the end of the erection device body perpendicular to the bridge axis, are positioned on both sides of the main cable perpendicular to the bridge axis, and the suspension structure before erection is connected to a second suspension member that is connected to the lower end of each first suspension member and extends perpendicular to the bridge axis. Therefore, the load of the heavy suspension structure is not applied to the center of the erection device body perpendicular to the bridge axis, and the strength of the center of the erection device body perpendicular to the bridge axis can be reduced accordingly. Furthermore, after the hanger cable suspended from the main cable is connected to the suspension structure, the connection between the lower end of the first suspension member on the outside in the direction perpendicular to the bridge axis and the second suspension member is released, and the second suspension member, which is connected to the first suspension member on the inside in the direction perpendicular to the bridge axis, is moved inward in the direction perpendicular to the bridge axis to a position where contact with the hanger cable can be avoided when moving in the direction of the bridge axis. As a result, when the erection device with each suspension member suspended is moved along the main cable to the erection position of the next suspension structure, each suspension member does not come into contact with the hanger cable and passes to the side of the hanger cable without obstruction. [Effects of the Invention]

[0013] According to the present invention, since the load of the suspension structure, which is a heavy object, is not applied to the center of the erection device body in the direction perpendicular to the bridge axis, a bending moment due to the suspension load of the suspension structure does not occur throughout the entire erection device body as in the conventional method, and the strength of the erection device body can be reduced accordingly. As a result, the structure of the erection device body can be simplified and its weight can be significantly reduced, so the required capacity of equipment used for the installation and movement of the erection device, such as the tower crane used for assembling and disassembling the erection device body and the tower winch used for moving the erection device along the main cable, can be reduced, improving constructability and reducing costs. In particular, even when the spacing between the main cables is wide, the weight increase of the erection device body can be suppressed, which is extremely advantageous in the erection of such wide suspension bridges. Furthermore, when moving the erection device, from which each suspension member is suspended, along the main cable to the erection position of the next suspended structure, each suspension member does not come into contact with the hanger cable and can pass alongside the hanger cable without obstruction. Therefore, even in an erection method in which a suspended structure is lifted by a second suspension member connected to a pair of first suspension members arranged on both sides of the main cable, the erection device can be easily moved along the main cable without the suspension members interfering with the hanger cable. [Brief explanation of the drawing]

[0014] [Figure 1] Schematic side view of a suspension bridge showing one embodiment of the present invention. [Figure 2] Schematic front view of the suspension bridge [Figure 3] Front view of the main components of the suspension structure erection device. [Figure 4] Plan view of the second suspension member [Figure 5] Plan view of the second suspension member showing the movable part extended. [Figure 6] Side view of a suspension structure erection device showing the suspension structure erection process. [Figure 7] Side view of a suspension structure erection device showing the suspension structure erection process. [Figure 8] Front view of the main parts of the suspension structure erection device showing the suspension structure erection process. [Figure 9] Side view of a suspension structure erection device showing a suspension structure erection process [Figure 10] Front view of the main part of a suspension structure erection device showing a suspension structure erection process [Figure 11] Front view of the main part of a suspension structure erection device showing a suspension structure erection process [Figure 12] Side view of a suspension structure erection device showing a suspension structure erection process

Embodiment for Carrying Out the Invention

[0015] Figs. 1 to 12 show an embodiment of the present invention, and show a method and a device for erecting a suspension structure of a suspension bridge for lifting and erecting the suspension structure of the suspension bridge.

[0016] The suspension bridge 1 shown in the figure includes a main cable 3 spanned between main towers 2, and is configured to suspend a suspension structure 5 composed of a supplementary steel girder or the like by a plurality of hanger cables 4 connected to the main cable 3. In this embodiment, one main cable 3 is provided on each of both ends in the direction perpendicular to the bridge axis, and two hanger cables 4 are used at one hanging position.

[0017] Each main cable 3 is arranged one by one on one end side and the other end side in the direction perpendicular to the bridge axis, and a plurality of annular suspension fittings 6 for suspending each hanger cable 4 are attached to each main cable 3. Further, the suspension fitting 6 is provided with a connecting portion 6a to which the upper end of the hanger cable 4 is connected.

[0018] Connecting portions 4a and 4b are provided at the upper end and the lower end of each hanger cable 4, respectively, and the connecting portion 4b on the lower end side is connected to the suspension structure 5 side.

[0019] The suspension structure 5 has a first connecting part 5a to which the lower end of the hanger cable 4 is connected, and a second connecting part 5b to which the erection device 10, which will be described later, is connected. Two first connecting parts 5a are provided at one suspension position of the hanger cable 4, and a second connecting part 5b is provided between each of the first connecting parts 5a.

[0020] The erection device 10 used in the suspension structure erection method of this embodiment comprises an erection device body 20 formed to extend in a direction perpendicular to the bridge axis, a pair of traveling units 30 that support the erection device body 20 and can travel on the main cable 3, a pair of first suspension members 40 arranged on both sides of the main cable 3 in a direction perpendicular to the bridge axis and each having its upper end connected to the erection device body 10, second suspension members 50 connected to the lower end of each first suspension member 40 and to which the suspension structure 5 before erection is connected, and connecting members 60 that connect the second suspension members 50 arranged on both sides of the main cable 3 in a direction perpendicular to the bridge axis of the suspension bridge 1, and is installed across each main cable 3 on both sides in a direction perpendicular to the bridge axis as shown in Figure 2.

[0021] The erection device body 20 consists of end beam sections 21 positioned above each main cable 3, and a central beam section 22 of a truss structure extending perpendicular to the bridge axis between each end beam section 21. The end beam sections 21 are formed such that the central side in the longitudinal direction is higher than the end sides. Connecting sections 21a are provided at both ends in the longitudinal direction of the end beam section 21 to which the upper ends of the first suspension members 40 are connected, and the central side in the longitudinal direction of the end beam section 21 is rotatably connected to the traveling unit 30.

[0022] The traveling unit 30 comprises a unit body 31 positioned on the main cable 3, and wheels 32 that engage with the main cable 3 are provided at multiple locations along the longitudinal direction of the unit body 31 on the lower surface of the unit body 31. In addition, a rotatable support portion 31a is provided on the upper surface of the unit body 31 to which the end beam portion 21 of the erection device body 20 is rotatably connected, and the erection device body 20 is supported by the rotatable support portion 31a so that it is always horizontal due to its own weight.

[0023] Each first suspension member 40 consists of a strand jack 41 that is suspended from the end beam portion 21 of the erection device body 20 so as to be rotatable in a direction perpendicular to the bridge axis, and a strand 42 that lifts the suspension structure 5 by the strand jack 41, and is arranged so that the distance between it and the main cable 3 is equal.

[0024] The strand jack 41 is a well-known jacking device used for lifting and lowering heavy objects. It has a well-known configuration in which the strand 42 is continuously extended and retracted by repeatedly gripping and releasing the strand 42 while moving one of a pair of upper and lower clamping mechanisms (not shown) capable of gripping the strand 42 up and down with a hydraulic device. The upper end of the strand jack 41 is rotatably connected to the connecting portion 21a of the erection device body 20 in a direction perpendicular to the bridge axis.

[0025] The strand 42 consists of multiple PC steel wires, and its lower end is provided with a connecting portion 42a that connects to the suspension structure 5. The upper end of the strand 42 is wound onto a winding portion 43, which is a well-known strand winding device, and the winding portion 43 is positioned on the upper surface of the unit body 31 above the main cable 3.

[0026] The second suspension member 50 is made of a beam-shaped steel material extending perpendicular to the bridge axis, and each longitudinal end is provided with a connecting portion 51 to which the lower end of the strand 42 is connected, and a connecting portion 52 is provided in the longitudinal center to which it is connected to the suspension structure 5. The second suspension member 50 is also provided with a pair of widthwise movable portions 53, one end of which is rotatably connected to one longitudinal end of the second suspension member 50 (inward in the direction perpendicular to the bridge axis of the suspension bridge 1). By rotating the movable portions 53 and extending them toward the inward direction perpendicular to the bridge axis of the suspension bridge 1, the center of gravity G of the second suspension member 50 can be moved in the direction perpendicular to the bridge axis. In this case, a weight 53a is provided on the other end of each movable portion 53, and when each movable portion 53 is extended, the center of gravity G of the second suspension member 50 moves downward to the connecting portion 51 with the first suspension member 40 on the inward side perpendicular to the bridge axis.

[0027] The connecting member 60 consists of a strand jack 61 with one end connected to one of the second suspension members 50 perpendicular to the bridge axis, and a strand 62 with one end connected to the other of the second suspension members 50 perpendicular to the bridge axis, and the strand jack 61 is used to pull the two second suspension members 50 together. In this case, the strand jack 61 is connected to the connecting portion 51 on the inner side of one of the second suspension members 50 perpendicular to the bridge axis, and the strand 62 is connected to the connecting portion 51 on the inner side of the other second suspension member 50 perpendicular to the bridge axis.

[0028] Next, the method for erecting the suspension structure in this embodiment will be described with reference to Figures 6 to 12. In these figures, the process of erecting one of the stiffening girders, which is divided into multiple sections along the bridge axis, as the suspension structure 5 is shown.

[0029] First, as shown in Figure 6, two erection devices 10 are placed on the main cable 3 at intervals in the direction of the bridge axis, and the traveling units 30 are connected to each other by wires 11. In this case, one of the erection devices 10 is connected via wire 12 to a tower top winch (not shown), and the tower top winch moves each erection device 10 along the main cable 3. In addition, hanger cables 4 are suspended from each of the suspension fittings 6 of the main cable 3.

[0030] Here, the suspension structure 5 is transported below the erection site by a work vessel such as a barge (not shown), and the first suspension members 40 of each erection device 10 are connected to two locations on the suspension structure 5 in the bridge axis direction and two locations perpendicular to the bridge axis direction. At this time, the connecting portion 42a of the strand 42 of each first suspension member 40 is connected to the second connecting portion 5b of the suspension structure 5.

[0031] Next, as shown in Figures 6 and 7, the strands 42 are lifted by the strand jacks 41 of each first suspension member 40, thereby lifting the suspension structure 5 to the height of the installation position. At this time, in order to avoid contact with the existing suspension structure 5, the suspension structure 5 is lifted while being displaced by a distance S in the bridge axis direction relative to the end face of the existing suspension structure 5. On the other hand, since the load of the suspension structure 5 is applied to the main cable 3 from each first suspension member 40 via the end beam section 21 and the traveling unit 30 of the erection device body 20, the load of the suspension structure 5 is not applied to the central beam section 22 of the erection device body 20. That is, since the load of the suspension structure 5 is applied from the connection section 21a with each first suspension member 40 to the end beam section 21, the bending moment due to the load of the suspension structure 5 occurs only between the connection sections 21a of the end beam section 21. Furthermore, when lifting the suspension structure 5, the upper end of the strand 42 unwound from the strand jack 41 is wound onto the winding section 43.

[0032] Next, after connecting the lower ends of each hanger cable 4 to the first connecting parts 5a of the suspension structure 5, as shown in Figure 8, the movable part 53 of the second suspension member 50 is extended inward in the direction perpendicular to the bridge axis, releasing the connection between the lower end of the first suspension member 40 on the outside in the direction perpendicular to the bridge axis and the connecting part 51 of the second suspension member 50, and also releasing the connection between the connecting part 52 of the second suspension member 50 and the second connecting part 5b of the suspension structure 5. As a result, the suspension structure 5 is suspended by each hanger cable 4, as shown in Figure 9. At this time, the second suspension member 50 is suspended by one of the first suspension members 40 only at the connecting part 51 on the inside in the direction perpendicular to the bridge axis, but because the center of gravity G moves to the connection position with one of the first suspension members 40 due to the extension of the movable part 53, the second suspension member 50 is kept horizontal without tilting with the connection part 51 with the first suspension member 40 as the pivot point.

[0033] Next, as shown in Figures 10 and 11, the strand jacks 61 of the connecting member 60 pull the second suspension members 50 on both sides perpendicular to the bridge axis together, thereby moving each second suspension member 50 suspended from the first suspension member 40 inward in the direction perpendicular to the bridge axis to a position where contact with the hanger cable 4 can be avoided during movement in the bridge axis direction, which will be described later.

[0034] Subsequently, as shown in Figure 12, each erection device 10 is moved to the next erection position along the main cable 3 by being pulled by the wire 12. At this time, the second suspension member 50 is moved to a position where contact with the hanger cable 4 can be avoided, so that each first suspension member 40 and the second suspension member 50 passes to the side of the hanger cable 4.

[0035] As described above, according to this embodiment, a pair of first suspension members 40, whose upper ends are connected to the end beam portion 21 of the erection device body 20, are arranged on both sides of the main cable 3 perpendicular to the bridge axis, and the suspension structure 5 before erection is connected to a second suspension member 50 which is connected to the lower end of each first suspension member 40 and extends perpendicular to the bridge axis, and the suspension structure 5 is lifted up to the erection position by each suspension member 40, 50. As a result, the load of the heavy suspension structure 5 is not applied to the central beam portion 22 of the erection device body 20, and the strength of the central beam portion 22 of the erection device body 20 can be reduced accordingly.

[0036] In other words, since only the end beam section 21 of the erection device body 20 needs to have the strength to withstand the load of the suspension structure 5, a bending moment due to the suspension load of the suspension structure does not occur throughout the entire erection device body as in the conventional method, and the structure of the erection device body 20 can be simplified and its weight can be significantly reduced. As a result, the required capacity of equipment used for installing and moving the erection device 10, such as the tower crane used for assembling and disassembling the erection device body 20 and the tower winch used for moving the erection device 10 along the main cable 3, can be reduced, thereby improving constructability and reducing costs. In particular, even when the spacing between the main cables 3 is wide, the weight increase of the erection device body 20 can be suppressed, which is extremely advantageous when erecting such wide suspension bridges.

[0037] Furthermore, after connecting the hanger cable 4 suspended from the main cable 3 to the suspension structure 5, the connection between the lower end of the first suspension member 40 on the outer side perpendicular to the bridge axis and the second suspension member 50 is released. At the same time, the second suspension member 50, which is connected to the first suspension member 40 on the inner side perpendicular to the bridge axis, is moved inward perpendicular to the bridge axis to a position where contact with the hanger cable 4 can be avoided when moving in the bridge axis direction. As a result, when moving the erection device 10, from which each suspension member 40 and 50 is suspended, along the main cable to the erection position of the next suspension structure, each suspension member 40 and 50 does not come into contact with the hanger cable 4 and can pass alongside the hanger cable 4 without obstruction. As a result, even in an erection method as in this embodiment, in which a suspended structure 5 is lifted by a second suspension member 50 connected at both longitudinal ends to a pair of first suspension members 40 arranged on both sides of the main cable 3, the erection device 10 can be easily moved along the main cable 3 without the second suspension member 50 interfering with the hanger cable 4.

[0038] In this case, after connecting the hanger cable 4 and the suspension structure 5, the center of gravity G of the second suspension member 50 is shifted to the connection position with the first suspension member 40 on the inside in the direction perpendicular to the bridge axis by making the movable part 53, which is a component of the second suspension member 50, unevenly positioned in the direction perpendicular to the bridge axis. This releases the connection between the lower end of the first suspension member 40 on the outside in the direction perpendicular to the bridge axis and the second suspension member 50. As a result, after releasing the connection between the second suspension member 50 and the other first suspension member 40, the second suspension member 50 does not tilt, and the erection device 10 can be smoothly moved along the main cable 3 while maintaining the horizontal position of the second suspension member 50.

[0039] Furthermore, the second suspension members 50 located on both sides of the suspension bridge 1, on the main cable 3 side perpendicular to the bridge axis, are connected by a connecting member 60. By using the connecting member 60 to pull the second suspension members 50 together, the second suspension members 50 are moved inward in the direction perpendicular to the bridge axis. As a result, both the left and right second suspension members 50 can be moved simultaneously with a single connecting member 60, allowing for efficient work.

[0040] Furthermore, since the first suspension member 40 is constructed using a strand jack 41 that extends and retracts a strand 42 whose lower end is connected to the suspension structure 5, the suspension structure 5 can be easily lifted by the strand jack 42.

[0041] In this case, the winding section 43, which winds up the upper end of the strand 42, is positioned above the main cable 3 and is installed on the running unit 30 on the main cable 3. This has the advantage that the weight of the winding section 43 does not add to the erection device body 20, and the required strength of the erection device body 20 is not increased by the winding section 43.

[0042] Furthermore, the erection device 10 is equipped with a traveling unit 30 that can travel on the main cable 3, and the traveling unit 30 supports the erection device body 20 so that it can rotate around a horizontal axis extending perpendicular to the bridge axis. As a result, the erection device body 20 can be supported by the traveling unit 30 so that it is always horizontal due to its own weight, and even if the erection device 10 is tilted according to the position of the main cable 3 in the longitudinal direction, the first suspension member 40 connected to the erection device body 20 can always be kept in a vertical state. This allows the first suspension member 40 on the inside in the direction perpendicular to the bridge axis to rotate on the vertical plane, so that no horizontal force is applied to the first suspension member 40, and the first suspension member 40 can always rotate smoothly.

[0043] In the above embodiment, a pair of movable parts 53 are shown to be rotatably mounted on the second suspension member 50, but the center of gravity may also be moved by a movable part that is slidably mounted on the second suspension member 50.

[0044] Furthermore, in the above embodiment, one main cable 3 is provided on each end perpendicular to the bridge axis, and two hanger cables 4 are used at each suspension position. However, it is also possible to provide two main cables 3 on each end perpendicular to the bridge axis, or to use one hanger cable 4 at each suspension position.

[0045] Furthermore, the above-described embodiment is just one example of the present invention, and the present invention is not limited to what is described in the above-described embodiment. [Explanation of symbols]

[0046] 1...Suspension bridge, 3...Main cable, 4...Hanger cable, 5...Suspension structure, 10...Erection device, 20...Erection device body, 30...Travel unit, 40...First suspension member, 41...Strand jack, 42...Strand, 43...Winding device, 50...Second suspension member, 53...Movable part, 60...Connecting member.

Claims

1. In a method for erecting a suspension structure for a suspension bridge, the suspension structure comprises main cables arranged on both sides perpendicular to the bridge axis of the suspension bridge, a plurality of hanger cables spaced apart from each other in the direction of the bridge axis, and a suspension structure suspended from the main cables by each hanger cable, The erection device has a main body formed to extend perpendicular to the bridge axis across each of the aforementioned main cables, and is installed on the main cables so as to be movable in the bridge axis direction, A pair of first suspension members, whose upper ends are connected to the end of the erection device body perpendicular to the bridge axis, are arranged on both sides of the main cable perpendicular to the bridge axis, The suspension structure before erection is connected to a second suspension member that is connected to the lower end of each first suspension member and extends perpendicular to the bridge axis, Each suspension member lifts the suspended structure to the installation position, After connecting the hanger cable suspended from the main cable to the suspension structure, The connection between the lower end of the first suspension member on the outer side perpendicular to the bridge axis and the second suspension member is released, The second suspension member, which is connected to the first suspension member located on the inner side perpendicular to the bridge axis, is moved inward perpendicular to the bridge axis to a position where contact with the hanger cable can be avoided during movement in the bridge axis direction. The erection device, with each suspension member connected, is moved along the main cable to the erection position of the next suspension structure. A method for erecting a suspension structure of a suspension bridge, characterized by the features described herein.

2. After connecting the hanger cable and the suspension structure, By displacing a portion of the second suspension member inward in the direction perpendicular to the bridge axis, the center of gravity of the second suspension member is moved to the connection position with the first suspension member inward in the direction perpendicular to the bridge axis. The connection between the lower end of the first suspension member, which is on the outer side perpendicular to the bridge axis, and the second suspension member is released. The method for erecting a suspension structure for a suspension bridge according to feature 1.

3. The second suspension members, which are located on the main cable side on both sides perpendicular to the bridge axis of the suspension bridge, are connected to each other by a connecting member. The second suspension members are moved inward in the direction perpendicular to the bridge axis by pulling the second suspension members together using the connecting member. The method for erecting a suspension structure for a suspension bridge according to feature 1.

4. In a suspension structure erection device for a suspension bridge, which comprises main cables arranged on both sides perpendicular to the bridge axis of the suspension bridge, a plurality of hanger cables arranged at intervals in the direction of the bridge axis, and a suspension structure suspended from the main cables by each hanger cable, The erection device body is formed to extend perpendicular to the bridge axis across each of the aforementioned main cables and is installed on the main cables so as to be movable in the bridge axis direction, A pair of first suspension members are positioned on both sides of the main cable perpendicular to the bridge axis, with their upper ends connected to the end of the erection device body perpendicular to the bridge axis, Each first suspension member is connected to the lower end of a second suspension member, which is formed to extend perpendicular to the bridge axis and to which the suspension structure before erection is connected. The connection between the lower end of the first suspension member on the outer side perpendicular to the bridge axis and the second suspension member, which is connected to the suspension member on the inner side perpendicular to the bridge axis, is released, and the second suspension member is configured to be able to move inward perpendicular to the bridge axis to a position where contact with the hanger cable can be avoided during movement in the bridge axis direction. A suspension bridge suspension structure erection device characterized by the following features.

5. The second suspension member is configured such that its center of gravity can be moved to the connection point with the first suspension member located on the inner side perpendicular to the bridge axis, by distributing some of its components inward in the direction perpendicular to the bridge axis. The suspension structure erection device for a suspension bridge according to feature 4.

6. The second suspension member has a movable part rotatably connected to its inner end perpendicular to the bridge axis, and is formed so that the center of gravity can be moved inward perpendicular to the bridge axis by rotating the movable part and extending it inward perpendicular to the bridge axis. The suspension bridge suspension structure erection device according to feature 5.

7. The suspension bridge is equipped with connecting members that connect the second suspension members, which are respectively located on the main cable side on both sides perpendicular to the bridge axis. The connecting member is formed to move the second suspension members inward in the direction perpendicular to the bridge axis by pulling the second suspension members together. The suspension structure erection device for a suspension bridge according to feature 4.

8. Each of the first suspension members consists of a strand jack that extends and retracts a strand whose lower end is connected to the suspension structure. The suspension structure erection device for a suspension bridge according to feature 4.

9. A winding unit for winding the upper end of the aforementioned strand is positioned above the main cable. The suspension structure erection device for a suspension bridge according to feature 4.

10. The vehicle is equipped with a travel unit that can travel along the aforementioned main cable, The system is configured so that the erection device body is supported by a traveling unit so that it can rotate around a horizontal axis extending perpendicular to the bridge axis. The suspension structure erection device for a suspension bridge according to feature 4.

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