Method and device for erecting a suspended structure for a suspension bridge

Abstract

A method and device for erecting a suspended structure for a suspension bridge that can reduce the weight of the main body of the erection device. [Solution] A pair of first suspension members 40, each connected at its upper end to the end beams 21 of the installation device main body 20, are positioned on both sides of the main cable 3 in the direction perpendicular to the bridge axis, and a suspended structure 5 before installation is connected to second suspension members 50 connected to the lower ends of each first suspension member 40 and extending in the direction perpendicular to the bridge axis, and the suspended structure 5 is lifted to the installation position by each suspension member 40, 50, so that the load of the suspended structure 5, which is a heavy object, is not applied to the central beams 22 of the installation device main body 20, and the strength of the central beams 22 of the installation device main body 20 can be reduced. In addition, because the second suspension member 50 is moved inward in the direction perpendicular to the bridge axis to a position where it can avoid contact with the hanger cable 4, each suspension member 40, 50 does not come into contact with the hanger cable 4 and can pass alongside the hanger cable 4 without hindrance.

Description

[Technical Field]

[0001] The present invention relates to a method and device for erecting a suspended structure for a suspension bridge, for hoisting and erecting a suspended structure such as a stiffening girder in a suspension bridge to be erected over a river, a strait, or the like. [Background technology]

[0002] Generally, a suspension bridge erected over a river, strait, etc. is composed of a number of main towers spaced apart in the bridge axis direction, a main cable stretched between the main towers, a number of hanger cables spaced apart in the bridge axis direction, and a suspension structure such as a steel beam suspended from the main cable by each hanger cable.

[0003] When erecting such a suspension bridge, a main cable is stretched between the main towers, and then multiple suspension structures divided in the bridge axis direction are transported on water below the main cable using a barge or similar, and the suspension structures are then lifted to their erection position using an erection device installed on the main cable (see, for example, Patent Documents 1 and 2).

[0004] In addition, the erection device has an erection device main body that extends perpendicular to the bridge axis across main cables arranged on both ends perpendicular to the bridge axis, and is configured to lift suspended structures using hanging materials suspended from the erection device main body, and by running on the main cables, moves in the bridge axis direction to lift other suspended structures. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 50-9938 [Patent Document 2] Japanese Patent Application Publication No. 60-88705 Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned erection device, when the device moves in the bridge axis direction along the main cable, the hanging material suspended from the device body is positioned at a position offset perpendicular to the bridge axis relative to the main cable so that it does not interfere with the hanger cable, and therefore the hanging load of the suspended structure is transmitted to the main cable via the device body.

[0007] As a result, in the erection device body, the loading point, where the suspended structure is suspended, and the reaction support point located on the main cable are separated in the direction perpendicular to the bridge axis, so a bending moment due to the suspended load of the suspended structure occurs in the erection device body. For this reason, it is necessary to increase the bending strength of the erection device body, but in order to increase the strength, the erection device body must be made larger, which increases the weight of the erection device body accordingly.

[0008] In other words, an increase in the weight of the erection device itself affects the required capacity of the equipment used to set up and move the erection device, such as the tower-top crane used to assemble and dismantle the erection device, and the tower-top winch used to move the erection device along the main cable.In particular, for suspension bridges where the spacing between the main cables is wide, the erection device itself becomes even larger and heavier, which can cause problems such as restrictions on the equipment capacity for the entire suspension bridge erection work.

[0009] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a method and device for erecting a suspended structure for a suspension bridge that can reduce the weight of the main body of the erection device. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the present invention provides a method for erecting a suspension structure for a suspension bridge, which includes main cables arranged on both sides of the suspension bridge in the direction perpendicular to the bridge axis, 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 method comprising: using an erection device body formed to extend across each of the main cables in the direction perpendicular to the bridge axis, and which is installed on the main cables so as to be movable in the direction of the bridge axis; connecting the upper ends of first suspension members arranged in pairs on both sides of each main cable in the direction perpendicular to the bridge axis to the end sides of the erection device body in the direction perpendicular to the bridge axis; and connecting one second suspension member connected to the lower ends of the pair of first suspension members arranged on one side of the main cable in the direction perpendicular to the bridge axis and extending in the direction perpendicular to the bridge axis; The suspended structure before installation is connected to the other second suspension member that is connected to the lower end of a pair of first suspension members arranged on the main cable side and extends in a direction perpendicular to the bridge axis, and the suspension structure is lifted to the installation position using each suspension member, and the hanger cables suspended from each main cable are connected to the suspended structure. After that, the second suspension members are connected to each other using connecting members, the connection between the lower end of the first suspension member on the outside in the direction perpendicular to the bridge axis and each second suspension member is released, and the second suspension members are pulled together using the connecting members, so that the second suspension members connected to the first suspension member on the inside in the direction perpendicular to the bridge axis are moved inward in the direction perpendicular to the bridge axis to a position where they can avoid contact with the hanger cable when moving in the bridge axis direction, and the installation device in which the second suspension members are connected to each other with connecting members is moved along the main cable to the installation position of the next suspended structure.

[0011] Furthermore, in order to achieve the above-mentioned object, the present invention provides a suspension structure erection device for erecting a suspension bridge structure comprising main cables arranged on both sides of the suspension bridge in the direction perpendicular to the bridge axis, 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 device comprising: an erection device main body formed to extend across each of the main cables in the direction perpendicular to the bridge axis and installed on the main cables to be movable in the direction of the bridge axis; first suspension members arranged in pairs on both sides of each main cable in the direction perpendicular to the bridge axis, with their upper ends connected to the end side of the erection device main body in the direction perpendicular to the bridge axis; one second suspension member connected to the lower ends of the pair of first suspension members arranged on one side of the main cable in the direction perpendicular to the bridge axis and formed to extend in the direction perpendicular to the bridge axis; and a second suspension member connected to the lower end of the pair of first suspension members arranged in the direction perpendicular to the bridge axis and formed to extend in the direction perpendicular to the bridge axis, and a connecting member connecting the second suspension members so that they can be pulled together in the direction perpendicular to the bridge axis.The suspension structure before installation is connected to each second suspension member, and the suspension structure is lifted up to the installation position using each suspension member, and the hanger cables suspended from each main cable are connected to the suspension structure.After that, the second suspension members are connected together using the connecting member, and the connection between the lower end of the first suspension member on the outside in the direction perpendicular to the bridge axis and each second suspension member is released, and the second suspension members are pulled together using the connecting member, so that each second suspension member connected to the first suspension member on the inside in the direction perpendicular to the bridge axis can be moved inward in the direction perpendicular to the bridge axis to a position where it can avoid contact with the hanger cables when moving in the bridge axis direction.

[0012] As a result, a pair of first suspension members, whose upper ends are connected to the end sides of the installation device main body in the direction perpendicular to the bridge axis, are positioned on both sides of the main cable in the direction perpendicular to the bridge axis, and the suspension structure before installation is connected to the second suspension members that are connected to the lower ends of each first suspension member and extend in the direction perpendicular to the bridge axis.As a result, the load of the heavy suspension structure is not applied to the central side of the installation device main body in the direction perpendicular to the bridge axis, and it is possible to reduce the strength of the central side of the installation device main body in the direction perpendicular to the bridge axis. Furthermore, after the hanger cable suspended from the main cable is connected to the suspended 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 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 it can avoid contact with the hanger cable when moving in the bridge axis direction.As a result, when the erection device hanging each suspension member is moved along the main cable to the erection position of the next suspended structure, the each suspension member does not come into contact with the hanger cable and passes alongside the hanger cable without hindrance. [Effects of the Invention]

[0013] According to the present invention, the load of the heavy suspended structure is not applied to the center of the erection device body in the direction perpendicular to the bridge axis, so that bending moment caused by the suspended load of the suspended structure is not generated throughout the entire erection device body as in the conventional case, and the strength of the erection device body can be reduced accordingly. This simplifies the structure of the erection device body and achieves a significant weight reduction, thereby reducing the required capacity of equipment used to install and move the erection device, such as the tower-top crane used to assemble and dismantle the erection device body and the tower-top winch used to move the erection device along the main cable, thereby improving workability and reducing costs. In particular, since the weight of the erection device body can be suppressed even when the main cables are spaced widely apart, this is extremely advantageous for erecting such wide suspension bridges. Furthermore, when the erection device with each suspension member suspended is moved along the main cable to the erection position of the next suspended structure, the suspension members do not come into contact with the hanger cable and can pass alongside the hanger cable without any hindrance. 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 drawings]

[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 part of the suspended structure erection device [Figure 4] Plan view of the second hanging member [Figure 5] FIG. 10 is a plan view of the second suspending member showing the movable portion extended; [Figure 6] A side view of a suspended structure erection device showing the suspended structure erection process [Figure 7] A side view of a suspended structure erection device showing the suspended structure erection process [Figure 8] A front view of the main part of the suspended structure erection device showing the suspended structure erection process [Figure 9] A side view of a suspended structure erection device showing the suspended structure erection process [Figure 10] A front view of the main part of the suspended structure erection device showing the suspended structure erection process [Figure 11] A front view of the main part of the suspended structure erection device showing the suspended structure erection process [Figure 12] A side view of a suspended structure erection device showing the suspended structure erection process DETAILED DESCRIPTION OF THE INVENTION

[0015] 1 to 12 show one embodiment of the present invention, and show a method and device for erecting a suspended structure of a suspension bridge by hoisting it up.

[0016] The suspension bridge 1 shown in the figure is equipped with a main cable 3 stretched between main towers 2, and is configured to suspend a suspended structure 5 consisting of a steel beam or the like by a plurality of hanger cables 4 connected to the main cable 3. In this embodiment, each of the main cables 3 is suspended in the direction perpendicular to the bridge axis. (horizontal) The figure shows a structure in which hanger cables 4 are provided on both ends and two hanger cables 4 are used at each hanging position.

[0017] Each main cable 3 is arranged one at each end in the direction perpendicular to the bridge axis, and multiple annular hanging fittings 6 are attached to each main cable 3 to hang each hanger cable 4. The hanging fittings 6 also have connecting parts 6a to which the upper ends of the hanger cables 4 are connected.

[0018] Each hanger cable 4 is provided with connecting portions 4a, 4b at its upper and lower ends, respectively, and the connecting portion 4b on the lower end side is adapted to be connected to the suspended structure 5 side.

[0019] The suspended structure 5 has a first connecting portion 5a to which the lower end of the hanger cable 4 is connected, and a second connecting portion 5b to which the erection device 10 described later is connected, and two first connecting portions 5a are provided at one hanging position of the hanger cable 4, and a second connecting portion 5b is provided between each of the first connecting portions 5a.

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

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

[0022] The traveling unit 30 comprises a unit body 31 placed on the main cable 3, and wheels 32 that engage with the main cable 3 are provided on the underside of the unit body 31 at multiple locations in the longitudinal direction of the unit body 31. In addition, a rotation support part 31a to which the end side beam part 21 of the erection device body 20 is rotatably connected is provided on the upper surface of the unit body 31, and the erection device body 20 is supported by the rotation support part 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 side beam portion 21 of the erection device main body 20 so that it can rotate freely in a direction perpendicular to the bridge axis, and a strand 42 that lifts the suspended structure 5 using the strand jack 41, and is arranged so that the distances from the main cable 3 are equal to each other.

[0024] The strand jack 41 is a well-known jack device used for lifting and lowering heavy objects, and has a well-known configuration in which one of a pair of upper and lower clamp mechanisms (not shown) capable of gripping the strand 42 is moved up and down by a hydraulic device, thereby repeatedly gripping and releasing the strand 42 and continuously paying out and repaying the strand 42. The upper end of the strand jack 41 is connected to the connecting part 21a of the erection device main body 20 so as to be rotatable in a direction perpendicular to the bridge axis.

[0025] The strand 42 is made up of multiple PC steel wires, and at its lower end is provided a connecting part 42a that is connected to the suspended structure 5. The upper end of the strand 42 is adapted to be wound around a winding part 43 made up of a well-known strand winding device, and the winding part 43 is arranged on the top surface of the unit body 31 so as to be positioned above the main cable 3.

[0026] The second suspension member 50 is made of a beam-shaped steel material extending in the direction perpendicular to the bridge axis, and is provided with connecting parts 51 at both ends of its length to which the lower ends of the strands 42 are connected, as well as a connecting part 52 at the longitudinal center to which it is connected to the suspended structure 5. The second suspension member 50 is also provided with a pair of widthwise movable parts 53, one end of which is rotatably connected to one longitudinal end of the second suspension member 50 (the inner side in the direction perpendicular to the bridge axis of the suspension bridge 1), and is configured so that the center of gravity G of the second suspension member 50 can be moved in the direction perpendicular to the bridge axis by rotating the movable parts 53 and extending them toward the inner side in the direction perpendicular to the bridge axis of the suspension bridge 1. In this case, a weight 53a is provided at the other end of each movable part 53, and when each movable part 53 is extended, the center of gravity G of the second suspension member 50 moves below the connecting part 51 with the first suspension member 40, which is on the inner side in the direction perpendicular to the bridge axis.

[0027] The connecting member 60 consists of a strand jack 61 connected at one end to one of the second suspension members 50 in the direction perpendicular to the bridge axis, and a strand 62 connected at one end to the other second suspension member 50 in the direction perpendicular to the bridge axis, and the strand jack 61 is used to pull the second suspension members 50 together. In this case, the strand jack 61 is connected to the connecting part 51 on the inside of one of the second suspension members 50 in the direction perpendicular to the bridge axis, and the strand 62 is connected to the connecting part 51 on the inside of the other second suspension member 50 in the direction perpendicular to the bridge axis.

[0028] Next, a method for erecting a suspended structure according to this embodiment will be described with reference to Figures 6 to 12. The figures show the process of erecting one of the stiffening girders divided into multiple parts in the bridge axis direction as a suspended structure 5.

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

[0030] Here, the suspended structure 5 is transported below the installation position by a work vessel such as a barge (not shown), and each first suspension member 40 of each erection device 10 is connected to the suspended structure 5 at two locations in the bridge axis direction and two locations perpendicular to the bridge axis. 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 suspended structure 5.

[0031] Next, as shown in Figures 6 and 7, the strands 42 are pulled up by the strand jacks 41 of each first suspension member 40, thereby lifting the suspended structure 5 to the height of the installation position. At this time, to avoid contact with the existing suspended structure 5, the suspended structure 5 is lifted by being displaced a distance S in the bridge axis direction relative to the end face of the existing suspended structure 5. Meanwhile, the load of the suspended structure 5 is applied from each first suspension member 40 to the main cable 3 via the end side beams 21 of the erection device main body 20 and the traveling units 30, so the load of the suspended structure 5 is not applied to the central side beams 22 of the erection device main body 20. In other words, the load of the suspended structure 5 is applied to the end side beams 21 from the connecting parts 21a with each first suspension member 40, so the bending moment due to the load of the suspended structure 5 occurs only between the connecting parts 21a of the end side beams 21. When the suspended structure 5 is lifted, the upper end of the strand 42 unwound from the strand jack 41 is wound around the winding section 43.

[0032] Next, after connecting the lower end of each hanger cable 4 to each first connecting part 5a of the suspended structure 5, the movable part 53 of the second suspension member 50 is extended inward in the direction perpendicular to the bridge axis as shown in Figure 8, and the connection between the lower end of the first suspension member 40 on the outer side in the direction perpendicular to the bridge axis and the connecting part 51 of the second suspension member 50 is released, and the connection between the connecting part 52 of the second suspension member 50 and the second connecting part 5b of the suspended structure 5 is released. As a result, the suspended structure 5 is suspended by each hanger cable 4 as shown in Figure 9. At this time, only the connecting part 51 on the inner side in the direction perpendicular to the bridge axis of the second suspension member 50 is suspended by one of the first suspension members 40, but because the center of gravity G has moved 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 connecting part 51 with the first suspension member 40 as a fulcrum.

[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 it can avoid contact with the hanger cable 4 when moving in the bridge axis direction as described below.

[0034] 12, each installation device 10 is moved to the next installation position along the main cable 3 by being pulled by the wire 12. At that time, since the second suspension member 50 has been moved to a position where it can avoid contact with the hanger cable 4, each of the first suspension member 40 and the second suspension member 50 passes beside the hanger cable 4.

[0035] In this way, according to this embodiment, a pair of first suspension members 40, each connected at its upper end to the end side beam portion 21 of the erection device main body 20, are positioned on both sides of the main cable 3 in the direction perpendicular to the bridge axis, and the suspended structure 5 before erection is connected to a second suspension member 50 connected to the lower end of each first suspension member 40 and extending in the direction perpendicular to the bridge axis, and the suspended structure 5 is lifted up to the erection position by each suspension member 40, 50.As a result, the load of the suspended structure 5, which is a heavy object, is not applied to the central side beam portion 22 of the erection device main body 20, and the strength of the central side beam portion 22 of the erection device main body 20 can be reduced accordingly.

[0036] That is, only the end beams 21 of the erection device main body 20 need to be strong enough to withstand the load of the suspended structure 5, so bending moment due to the suspension load of the suspended structure does not occur throughout the entire erection device main body, as in the past, and the structure of the erection device main body 20 can be simplified and significantly reduced in weight. This reduces the required capacity of the equipment used to install and move the erection device 10, such as the tower-top crane used to assemble and dismantle the erection device main body 20 and the tower-top winch used to move the erection device 10 along the main cables 3, thereby improving workability and reducing costs. In particular, since the weight of the erection device main body 20 can be suppressed even when the interval between the main cables 3 is wide, this is extremely advantageous in erecting such wide suspension bridges.

[0037] Furthermore, after connecting the hanger cable 4 suspended from the main cable 3 to the suspended structure 5, 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 is released, and the second suspension member 50 connected to the first suspension member 40 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 4 can be avoided when moving in the bridge axis direction.Therefore, when the erection device 10 suspending each suspension member 40, 50 is moved along the main cable to the erection position of the next suspended structure, each suspension member 40, 50 does not come into contact with the hanger cable 4 and can pass alongside the hanger cable 4 without hindrance. As a result, even in an installation method such as this embodiment in which the suspended structure 5 is lifted by a second suspension member 50 whose both longitudinal ends are connected to a pair of first suspension members 40 arranged on both sides of the main cable 3, the installation 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 suspended structure 5, the movable part 53, which is a component of the second suspension member 50, is shifted inward in the direction perpendicular to the bridge axis, thereby moving the center of gravity G of the second suspension member 50 to the connection position with the first suspension member 40 on the inside in the direction perpendicular to the bridge axis, and the connection between the lower end side of the first suspension member 40 on the outside in the direction perpendicular to the bridge axis and the second suspension member 50 is released.Therefore, after the connection between the second suspension member 50 and the other first suspension member 40 is released, the second suspension member 50 does not tilt, and the erection device 10 can be moved smoothly along the main cable 3 while maintaining the second suspension member 50 in a horizontal position.

[0039] Furthermore, the second suspension members 50 arranged on both sides of the main cable 3 in the direction perpendicular to the bridge axis of the suspension bridge 1 are connected by connecting members 60, and the second suspension members 50 are moved inward in the direction perpendicular to the bridge axis by pulling the second suspension members 50 together with the connecting members 60. Therefore, the left and right second suspension members 50 can be moved simultaneously with one connecting member 60, allowing work to be carried out efficiently.

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

[0041] In this case, the winding section 43 that winds up the upper end of the strand 42 is positioned above the main cable 3 and is provided on the running unit 30 on the main cable 3, so the weight of the winding section 43 is not added to the erection device main body 20, which has the advantage that the required strength of the erection device main 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 main body 20 so that it can rotate freely around a horizontal axis extending in the direction perpendicular to the bridge axis. Therefore, the erection device main body 20 can be rotatably supported on the traveling unit 30 so that it is always horizontal due to its own weight, and the first suspension member 40 connected to the erection device main body 20 can be kept always vertical even if the erection device 10 tilts depending on the position in the longitudinal direction of the main cable 3. This allows the first suspension member 40 on the inside in the direction perpendicular to the bridge axis to rotate on a 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 rotatably attached to the second hanging member 50, but the center of gravity may also be moved by a movable part that is slidably attached to the second hanging member 50.

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

[0045] The above embodiment is an example of the present invention, and the present invention is not limited to the above embodiment. [Explanation of symbols]

[0046] 1...suspension bridge, 3...main cable, 4...hanger cable, 5...suspended structure, 10...erection device, 20...erection device main body, 30...traveling 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. A method for erecting a suspension structure for a suspension bridge, which includes a main cable arranged on each side of the suspension bridge in the direction perpendicular to the bridge axis, a plurality of hanger cables arranged at intervals in the bridge axis direction, and a suspension structure suspended from the main cable by each hanger cable, The erection device has an erection device body formed to extend in a direction perpendicular to the bridge axis along each of the main cables, and is installed on the main cables so as to be movable in the bridge axis direction. The upper ends of the first suspension members arranged in pairs on both sides of each main cable in the direction perpendicular to the bridge axis are connected to the end sides of the erection device body in the direction perpendicular to the bridge axis, The suspension structure before erection is connected to one second suspension member that is connected to the lower end of a pair of first suspension members arranged on one side of the main cable in the direction perpendicular to the bridge axis and extends in the direction perpendicular to the bridge axis, and to the other second suspension member that is connected to the lower end of the pair of first suspension members arranged on the other side of the main cable in the direction perpendicular to the bridge axis and extends in the direction perpendicular to the bridge axis. The suspended structure is lifted to the erection position by each suspension member, After connecting the hanger cables suspended from each main cable to the suspended structure, The second hanging members are connected to each other by connecting members, The connection between the lower end side of the first suspension member on the outer side in the direction perpendicular to the bridge axis and each second suspension member is released, By drawing the second suspension members together with the connecting members, each second suspension member 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 it can avoid contact with the hanger cable when moving in the bridge axis direction, The erection device in which the second suspension members are connected by the connecting members is moved along the main cable to the erection position of the next suspended structure. A method for erecting a suspended structure for a suspension bridge.

2. After connecting the hanger cable and the suspended structure, By displacing some of the components 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 a connection position with the first suspension member on the inside in the direction perpendicular to the bridge axis, The connection between the lower end of the first suspension member on the outer side in the direction perpendicular to the bridge axis and the second suspension member is released.

2. The method for erecting a suspended structure of a suspension bridge according to claim 1.

3. A suspension structure erection device for erecting a suspension bridge structure includes a main cable arranged on each side of the suspension bridge in the direction perpendicular to the bridge axis, a plurality of hanger cables arranged at intervals in the bridge axis direction, and a suspension structure suspended from the main cable by each hanger cable. an erection device main body formed to extend in a direction perpendicular to the bridge axis across each of the main cables and installed on the main cables so as to be freely movable in the bridge axis direction; a pair of first suspension members arranged on both sides of each main cable in the direction perpendicular to the bridge axis, with their upper ends connected to the end of the erection device body in the direction perpendicular to the bridge axis; a second suspension member connected to the lower end of a pair of first suspension members arranged on one main cable side in the direction perpendicular to the bridge axis and formed to extend in the direction perpendicular to the bridge axis; a second suspension member that is connected to the lower end of the pair of first suspension members arranged on the other main cable side in the direction perpendicular to the bridge axis and is formed to extend in the direction perpendicular to the bridge axis; a connecting member that connects the second suspension members so that they can be pulled together in a direction perpendicular to the bridge axis; The suspension structure before erection is connected to each second suspension member, and the suspension structure is lifted to the erection position by each suspension member, and the hanger cables suspended from each main cable are connected to the suspension structure. After that, each second suspension member is connected to each other by the connecting member, and the connection between the lower end side of the first suspension member on the outside in the direction perpendicular to the bridge axis and each second suspension member is released, and the second suspension members are pulled together by the connecting member, so that each second suspension member connected to the first suspension member on the inside in the direction perpendicular to the bridge axis can be moved inward in the direction perpendicular to the bridge axis to a position where contact with the hanger cables can be avoided when moving in the bridge axis direction. A suspension bridge suspension structure erection device characterized by the above.

4. The second suspension member is configured so that its center of gravity can be moved to a connecting position with the first suspension member on the inside in the direction perpendicular to the bridge axis by distributing some of its components inward in the direction perpendicular to the bridge axis.

4. The suspension structure erection device for a suspension bridge according to claim 3.

5. The second suspension member has a movable part that is rotatably connected to the end on the inside in the direction perpendicular to the bridge axis, and is formed so that the center of gravity can be moved inward in the direction perpendicular to the bridge axis by rotating the movable part and extending it toward the inside in the direction perpendicular to the bridge axis.

5. The suspension structure erection device for a suspension bridge according to claim 4.

6. Each of the first suspension members is a strand jack that feeds and rewinds a strand connected to the suspension structure at its lower end.

4. The suspension structure erection device for a suspension bridge according to claim 3.

7. A winding section for winding the upper end of the strand is disposed above the main cable.

7. The suspension structure erection device for a suspension bridge according to claim 6.

8. a traveling unit capable of traveling on the main cable, The running unit supports the erection device body so that it can rotate freely around a horizontal axis extending perpendicular to the bridge axis.

4. The suspension structure erection device for a suspension bridge according to claim 3.

Images