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] The upper end of a suspension member 40 supported by an erection device main body 20 is connected to a main cable 3, and the pre-erected suspended structure 5 is connected to the lower end of the suspension member 40, and the suspended structure 5 is lifted to the erection position by the suspension member 40, so that the load of the heavy suspended structure 5 is not applied to the erection device main body 20, and the strength of the erection device main body 20 can be reduced accordingly. Also, the suspension member 40 supported by the erection device main body 20 is moved by a support mechanism 50 to a predetermined position perpendicular to the bridge axis where contact with the hanger cable 4 can be avoided, so the suspension member 40 does not come into contact with the hanger cable 4 when moving in the bridge axis direction, and can pass beside 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 the steps of: 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 to be able to move freely in the direction of the bridge axis; The support mechanism The upper end of the supported hanging member is connected to the main cable, and the hanging structure before installation is connected to the lower end of the hanging member, and the hanging structure is lifted up to the installation position by the hanging member, and the hanger cable suspended from the main cable is connected to the hanging structure, and then the connection between the lower end of the hanging member and the hanging structure is released, and the connection between the upper end of the hanging member and the main cable is released, support mechanism The suspension member supported by the suspension cable is moved in the direction of the bridge axis to a position where it can avoid contact with the hanger cable. By support mechanism The installation device supporting the suspension members is moved perpendicular to the bridge axis, and is moved along the main cable to the installation position of the next suspension structure.

[0011] In order to achieve the above object, the present invention provides a suspension structure erection device for erecting a suspension bridge structure, which comprises 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 movably installed on the main cables in the direction of the bridge axis, and an erection device whose upper end is detachably connected to the main cables. At the same time , bottom side of hanging structure Detachable to Concatenation The suspended structure connected to the lower end is then lifted up to the erection position. It is equipped with a suspension member and a support mechanism that supports the upper end of the suspension member and can move the suspension member, which has been released from connection with the main cable, in a 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.

[0012] As a result, the upper end of the suspension member supported by the erection device main body is connected to the main cable, and the suspended structure before installation is connected to the lower end of the suspension member, so the load of the heavy suspended structure is not applied to the erection device main body, and the strength of the erection device main body can be reduced accordingly. Also, after the hanger cable suspended from the main cable is connected to the suspended structure, the connection between the lower end of the suspension member and the suspended structure is released, and the connection between the upper end of the suspension member and the main cable is released, and the suspension member supported by the erection device main body is moved to a predetermined position perpendicular to the bridge axis where it can avoid contact with the hanger cable. Therefore, when the erection device supporting the suspension member is moved along the main cable to the installation position of the next suspended structure, the suspension member does not come into contact with the hanger cable and passes next to 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 erection device main body, so that bending moment due to the suspended load of the suspended structure does not occur on the erection device main body as in the past, and the strength of the erection device main body can be reduced accordingly. As a result, the structure of the erection device main body can be simplified and significantly reduced in weight, which reduces 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 main 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 main 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 supporting the suspension members 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 suspension members connected to 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] Side view of the suspended structure erection device [Figure 5] A side view of the suspended structure erection device showing the suspended structure erection process [Figure 6] A side view of the suspended structure erection device showing the suspended structure erection process [Figure 7] A front view of the main part of the suspended structure erection device showing the suspended structure erection process [Figure 8] A side view of the suspended structure erection device showing the suspended structure erection process [Figure 9] A front view of the main part of the suspended structure erection device showing the suspended structure erection process DETAILED DESCRIPTION OF THE INVENTION

[0015] 1 to 9 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 suspended structure 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] In this embodiment Erection of suspended structures Used in the method Erection The device 10 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 can run on the main cable 3, a hanging member 40 that is detachably connected at its upper end to the main cable 3 and to which a suspended structure 5 can be connected at its lower end, and a support mechanism 50 that supports the upper end of the hanging member 40 and can move the hanging member 40 in a direction perpendicular to the bridge axis when it has been released from connection with the main cable 3 to a position where it can avoid contact with the hanger cable 4 when moving in the bridge axis direction, and is 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 made of beam-like members with a truss structure, and is formed so that the width and height dimensions at both longitudinal ends are smaller than those at the longitudinal center, and is rotatably supported by each traveling unit 30. In addition, at both longitudinal ends of the erection device main body 20, connecting parts 21 to which the support mechanisms 50 are connected are provided, and each connecting part 21 is formed to extend downward from the erection device main body 20.

[0022] The traveling unit 30 includes a unit body 31 disposed 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 support member 33 that supports the erection device body 20 is provided on the upper surface of the unit body 31. The support member 33 is made up of a beam 33a extending in the longitudinal direction of the unit body 31 and a pair of legs 33b extending diagonally downward from both ends of the beam 33a in the longitudinal direction, and by connecting the lower surface of the beam 33a to the upper surface of the erection device body 20 via a pivot support part 33c, the erection device body 20 is supported so that it is always horizontal due to its own weight.

[0023] The suspension member 40 comprises a suspension fitting 41 attached to the main cable 3, a strand jack 42 detachably suspended from the suspension fitting 41, and a strand 43 that lifts the suspended structure 5 with the strand jack 42.

[0024] The sling 41 is made of a ring-shaped member attached to the outer circumferential surface of the main cable 3 and has a connecting portion 41 a extending downward from the main cable 3 .

[0025] The strand jack 42 is a well-known jack device used for lifting and lowering heavy loads, 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 43 is moved up and down by a hydraulic device, thereby repeatedly gripping and releasing the strand 43 and continuously paying out and repaying the strand 43. In addition, a connecting part 42a that can be detachably connected to the connecting part 41a of the lifting fitting 41 is provided at the upper end of the strand jack 42.

[0026] The strand 43 is made up of a plurality of PC steel wires, and has a connecting portion 43a at its lower end that is connected to the suspended structure 5. The upper end of the strand 43 is adapted to be wound around a winding portion 44 consisting of a well-known strand winding device, and the winding portion 44 is arranged on the upper surface of the unit body 31 so as to be located above the main cable 3. In this case, the upper end of the strand 43 is arranged along a support member 51 of the support mechanism 50, which will be described later, and is wound around the winding portion 44 via the upper surface of the installation device body 20.

[0027] The support mechanism 50 has a support member 51 whose one end is rotatably connected to the erection device main body 20, and a hydraulic jack 52 as a driving means for rotating the support member 51, and the other end of the support member 51 is rotatably connected to the upper end side of the hanging member 40.

[0028] The support member 51 is formed so as to be bent in an L-shape, and one end thereof is connected to the underside of the installation device main body 20 via a rotating support part 51a. In this case, the rotating support part 51a is disposed between the connecting part 21 of the installation device main body 20 and the main cable 3. The other end side of the support member 51 is formed so as to extend toward the main cable 3, and its tip is connected to the connecting part 42a on the upper end side of the strand jack 42.

[0029] The hydraulic jack 52 is a well-known clevis jack, with one end rotatably connected to the lower end of the connecting portion 21 of the erection device main body 20 and the other end rotatably connected to the L-shaped bent portion of the support member 51. The hydraulic jack 52 extends and contracts in the longitudinal direction, thereby rotating the support member 51 around the rotation support portion 51a on one end side of the support member 51 as a fulcrum.

[0030] Next, a method for erecting a suspended structure according to this embodiment will be described with reference to Figures 5 to 9. 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.

[0031] First, as shown in Figure 5, 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.

[0032] Here, the suspended structure 5 is transported below the installation position by a work vessel such as a barge (not shown), and the suspension members 40 of each erection device 10 are 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 jack 42 of each suspension member 40 is connected to the connecting portion 41a on the main cable 3 side, and the connecting portion 43a of the strand 43 is connected to the second connecting portion 5b of the suspended structure 5.

[0033] Next, the strand 43 is pulled up by the strand jacks 42 of each suspension member 40, thereby lifting the suspended structure 5 to the height of the installation position. At that 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 to the main cable 3 via the suspension fittings 41 to which the upper ends of the strand jacks 42 are connected, so the load of the suspended structure 5 is not applied to the erection device main body 20. Furthermore, when lifting the suspended structure 5, the upper end side of the strand 43 paid out from the strand jack 42 is wound up by the winding section 44.

[0034] Next, the lower end of each hanger cable 4 is connected to each first connecting part 5a of the suspended structure 5, and then the connection between the lower end of the strand 43 of the suspension member 40 and the second connecting part 5b of the suspended structure 5 is released as shown in Figure 6. This causes the suspended structure 5 to be supported by each hanger cable 4.

[0035] Next, as shown in Figure 7, the connection between the connecting portion 42a of the strand jack 42 of the suspension member 40 and the connecting portion 41a of the suspension fitting 41 is released. This work is performed by a worker on a scaffold (not shown) located below the main cable 3. Next, the strand jack 42 of the suspension member 40 is moved to a predetermined position perpendicular to the bridge axis by the support mechanism 50. That is, by rotating the support member 51 by the hydraulic jack 52 of the support mechanism 50, the strand jack 42 supported on the other end of the support member 51 is moved to a position where it can avoid contact with the hanger cable 4 when moving in the bridge axis direction, which will be described later.

[0036] Thereafter, as shown in Fig. 8, each erection device 10 is pulled by the wire 12 to move it to the next erection position along the main cable 3. At that time, the strand jacks 42 of the suspending members 40 have been moved by the support mechanisms 50 to positions where they can avoid contact with the hanger cables 4, so that the suspending members 40 supported by the support mechanisms 50 pass beside the hanger cables 4, as shown in Fig. 9.

[0037] As described above, according to this embodiment, the upper ends of the suspension members 40 supported by the installation device main body 20 are connected to the main cables 3, and the pre-erected suspended structure 5 is connected to the lower ends of the suspension members 40, and the suspended structure 5 is lifted up to the installation position by the suspension members 40, so the load of the suspended structure 5, which is a heavy object, is not applied to the installation device main body 20, and the strength of the installation device main body 20 can be reduced accordingly. In other words, since the installation device main body 20 only needs to have strength against the loads of the strand jacks 42 and strands 43 of the suspension members 40, no bending moment due to the suspension load of the suspended structure is generated in the installation device main body as in the conventional case, and the structure of the installation device main body 20 can be simplified and significantly lighter. 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 cable 3, thereby improving workability and reducing costs. In particular, even when the spacing between the main cables 3 is wide, the weight of the erection device main body 20 can be kept down, making it extremely advantageous for erecting such wide suspension bridges.

[0038] Furthermore, after connecting the hanger cables 4 suspended from the main cables 3 to the suspended structure 5, the connection between the lower ends of the hanging members 40 and the suspended structure 5 is released, and the connection between the upper ends of the hanging members 40 and the main cables 3 is released, and the hanging members 40 supported by the erection device main body 20 are moved by the support mechanisms 50 to a predetermined position perpendicular to the bridge axis where contact with the hanger cables 4 can be avoided. Therefore, when the erection device 10 supporting the hanging members 40 is moved along the main cables to the erection position of the next suspended structure, the hanging members 40 do not come into contact with the hanger cables 4 and can pass by the sides of the hanger cables 4 without hindrance. As a result, even in an erection method in which the suspended structure 5 is lifted by the hanging members 40 connected to the main cables 3, the erection device 10 can be easily moved along the main cables 3 without the hanging members 40 interfering with the hanger cables 4.

[0039] In this case, the support mechanism 50 is composed of a support member 51 whose one end is rotatably connected to the erection device main body 20, and a hydraulic jack 52 that rotates the support member 51, and the upper end of the suspension member 40 is connected to the other end of the support member 51.Therefore, by rotating the support member 51, the suspension member 40 can be easily moved in a direction perpendicular to the bridge axis, making it easy to relocate the erection device 10.

[0040] Furthermore, the suspension member 40 is constructed of a strand jack 42 that pays out and repays a strand 43 whose lower end is connected to the suspended structure 5, and the upper end of the strand jack 42 is configured to be detachable from the main cable 3 side, so that the suspended structure 5 can be easily lifted by the strand jack 42 connected to the main cable 3 side.

[0041] In this case, strand 4 3 Since the winding section 44 that winds up the upper end of the main cable 3 is positioned above the main cable 3, the weight of the winding section 44 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 44.

[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 perpendicular to the bridge axis, so that 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 support member 51 attached to the erection device main body 20 can always be kept vertical even if the erection device 10 tilts depending on the position of the main cable 3 in the longitudinal direction. This allows the support member 51 to rotate on a vertical plane, so that no horizontal force is applied to the support member 51, and the support member 51 can always rotate smoothly.

[0043] In addition, the above embodiment shows a support mechanism 50 in which the support member 51 is rotated, but the support member may be slid to move the suspension member 40 in a direction perpendicular to the bridge axis.

[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...Suspension structure, 10...Erection device, 20...Erection device main body, 30...Traveling unit, 40...Suspension member, 42...Strand jack, 43...Strand, 44...Winding device, 50...Support mechanism, 51...Support member, 52...Hydraulic jack.

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 end side of the hanging member supported by the support mechanism provided on the erection device body is connected to the main cable, The suspension structure before erection is connected to the lower end of the suspension member, The suspended structure is lifted to the erection position by the suspension member, After connecting the hanger cable suspended from the main cable to the suspended structure, The connection between the lower end of the hanging member and the hanging structure is released, and Release the connection between the upper end of the hanging member and the main cable, The suspension member supported by the support mechanism is moved in a direction perpendicular to the bridge axis by the support mechanism to a position where contact with the hanger cable can be avoided when moving in the bridge axis direction, The erection device supporting the hanging member is moved along the main cable to the erection position of the next hanging structure. A method for erecting a suspended structure for a suspension bridge.

2. The support mechanism rotates a support member whose one end is rotatably connected to the erection device body and whose other end is connected to the upper end of the suspension member, thereby moving the suspension member in a direction perpendicular to the bridge axis.

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 suspension member whose upper end side is detachably connected to the main cable and whose lower end side is detachably connected to the suspended structure, and which lifts the suspended structure connected to its lower end side to an erection position; The support mechanism supports the upper end of the suspension member and is capable of moving the suspension member, which has been released from connection with the main cable, in the direction perpendicular to the bridge axis to a position where it can avoid contact with the hanger cable when moving in the direction of the bridge axis. A suspension bridge suspension structure erection device characterized by the above.

4. The support mechanism has a support member rotatably connected at one end to the erection device body and a drive means for rotating the support member, and the upper end of the hanging member is connected to the other end of the support member.

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

5. The lower end of the suspension member is a strand jack that feeds and rewinds a strand connected to the suspended structure, and the upper end of the strand jack is configured to be detachable from the main cable.

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

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

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

7. 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.

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