JP2720339B2 - Cable laying method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laying a cable when constructing a suspension bridge or a similar structure having a suspension structure.

[0002]

2. Description of the Related Art In recent years, in a civil engineering structure, there are various methods for constructing a column-free space with a long span. Above all, the long span of the structure by the suspension structure, especially,
In the civil engineering field, as in the case of a suspension bridge, the history is old,
Its usefulness will be clear in the future.

[0003] In general, a suspension bridge is constructed in such a manner that a main cable is laid between tower tops of main tower steel frames, and then a main girder steel frame is laid between main tower steel frames.

That is, as shown in FIG. 7A, after the main tower steel frames 1, 1 are constructed, as shown in FIG. 7B, a pilot wire (main cable pulling wire) 10 is mainly used. The main cable 7 connected to the other end of the pilot wire 10 is developed by bridging one end of the pilot wire 10 with a winch 9 to extend between the tower tops of the tower steel frames 1, 1. Erect between the tower tops, and then
As shown in FIG. 7 (c), the hanger cables 13 are attached to the main cable 7 via hanging hardware, and the main tower steel frames 1, 1 are suspended while being supported by the hanger cables 13.
The main girder steel frame 2 was erected between them.

However, in the above cable laying method, when the main cable 7 is unfolded, as shown in FIG. 7B, the main cable 7 is largely bent downward before and after the top of the tower. In addition to being easily damaged, a large force is required to deploy the main cable 7 (pulling by the pilot wire 10), and the winch 9
It was necessary to install a large-scale device, and it was necessary to attach a complicated guide roller to the top of the tower.

In addition, since the operation of attaching the hanger cable to the main cable 7 and the operation of attaching the hanger cables 13 to the hanger cable are performed at a high place, a complicated temporary structure is required, and the construction period becomes long. There were also difficulties in safety management.

[0007]

When a place to be constructed is to be constructed under bad conditions such as the sea or a deep valley, the above-mentioned conventional method may have to be used. However, for example, in the case of constructing a suspension bridge constructed over a road or a suspension structure similar thereto, it is not always necessary to load a lifting machine such as a crane truck near the main tower steel frame. It is not necessary to adopt the above-mentioned conventional method, and the main girder steel frame can be temporarily supported by temporary supporting columns erected on the ground, so it can be constructed prior to the installation of the main cable It should be.

The present invention has been made in view of the above, and an object of the present invention is to provide a method of laying a cable which can lay a main cable in a short period of time and at low cost and which is advantageous in quality and safety management. To provide.

[0009]

The technical means taken by the present invention to solve the above problems are as follows. That is, the method of erection of the cable according to the present invention is such that, after erection of the main girder steel frame between the main tower steel frames, the main cable is deployed on the main girder steel frame, the hanger cable is attached to the main cable, and then the lifting machine is used. The main cable is lifted to the top of the main tower steel frame.

[0010]

According to the above construction, since the main cable is deployed on the main girder steel frame, the main cable is less bent when the main cable is deployed, and a large force is applied to the deployment of the main cable (pulling by the pilot wire). It does not require a complicated guide roller.

Also, various operations on the main cable, for example, mounting of a hanging hardware for mounting a hanger cable,
Mounting of the hanger cable to the hanging hardware, reworking of the rust prevention processing part of the main cable and the hanger cable, etc. can all be done by working on the main girder steel frame,
Work at height will be significantly reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG.
After constructing, the main girder steel frame 2 is erected between the main tower steel frames 1 and 1 as shown in FIG. 3 is the main tower steel frame 1,
.. Are temporary supports that support the main girder steel frame 2 located outside the main tower steel frames 1 and 1.

The main girder steel frame 2 is erected, for example, as shown in FIG. 3, by suspending a main girder steel unit 2a provided with a temporary support column 3 with a hoisting machine 5 such as a crane truck and connecting it to the main tower steel frame 1. The main girder steel unit 2a with the same temporary support 3
Can be carried out by a method such as adding

Although not shown, the necessary number of temporary columns 3 are previously erected at predetermined intervals on the ground, and thereafter, the main girder steel unit 2a is connected to the main tower steel frame 1 or extended, thereby performing A main girder steel frame 2 may be provided between the main tower steel frames 1 and 1. In any case, the temporary support column 3 is removed when the support of the main girder steel frame 2 becomes unnecessary.

In the case where the span is relatively short or the scale of the main girder steel frame unit 2a is small, as shown in FIG. 4, a temporary suspension wire 6 is suspended from the main tower steel frame 1 and the main girder steel frame is used by the suspension wire 6. The main girder steel frame 2 may be erected while supporting the unit 2a.

Thereafter, FIG. 1 (c) and FIG. 2 (a)
As shown in FIG. 2, the main cable 7 is deployed on the main girder steel frame 2. That is, a drum 8 having a main cable 7 wound on one end side of the main girder steel frame 2 and a winch 9 on the other end side.
The main cable 7 connected to the other end of the pilot wire 10 is deployed on the main girder steel frame 2 by pulling one end of the pilot wire 10 by the winch 9. Reference numeral 7a in FIG. 5 denotes a fixing hardware at the tip of the main cable 7.

The fixing metal 7a at the end of the main cable may be moved on the main girder steel frame 2 by placing it on a trolley. In this embodiment, as shown in FIG. 5, the single pipe 11a is appropriately fixed by a clamp 11b. In addition, the resin pipe 11c is rotatably fitted to the horizontal single pipe 11a and the vertical single pipe 11a connected to both sides thereof to form the runway 11 for the main cable 7, and the fixing is performed. Mounting the hardware 7a on the sled body 12,
Moving on runway 11.

After the main cable 7 has been deployed, the hanging work for attaching the hanger cable to the main cable 7 and the hanger cables 13... Attachment, reworking of the rust-prevention processing section of the main cable 7 and the hanger cables 13.

Thereafter, as shown in FIG. 2 (b) and FIG. 6, the hoist 5
As a result, the main cable 7 is lifted to the top of the main tower steel frames 1 and 1 to fix a predetermined position of the main cable 7 to the saddle 14 at the top of the tower and to fix both ends of the main cable 7 to the main girder steel frame 2. . Numerals 15 are chill holes for gradually feeding out the spare wires 16 connected to both ends of the main cable 7 as the main cable 7 is lifted.

In this state, as shown in FIG.
After fixing the lower ends of the hanger cables 13 to the main girder steel frame 2, the temporary columns 3 are removed.

[0021]

According to the present invention, as described above, since the main cable is deployed on the steel frame of the main girder, when the main cable is deployed, there is little bending of the main cable, and the main cable can be deployed (pulled by the pilot wire). Does not require great power. Therefore, the main cable can be deployed using a relatively small winch, and damage to the main cable can be reduced. Also,
All operations on the main girder, such as attaching the hanging hardware for attaching the hanger cable, attaching the hanger cable to the hanging hardware, and reworking the rust-proofing part of the main cable and hanger cable, etc. , Work at height is significantly reduced. The main cable can be laid in a short period of time and at low cost, which is advantageous in quality and safety management.

[Brief description of the drawings]

FIG. 1 is a process explanatory view of a cable erection method according to the present invention.

FIG. 2 is an explanatory view of a step that follows the step of FIG. 1;

FIG. 3 is an explanatory view of a method of erection of a main girder steel frame.

FIG. 4 is an explanatory diagram of another method of erection of a main girder steel frame.

FIG. 5 is a perspective view of a main part for explaining a step of developing a main cable.

FIG. 6 is a perspective view of a main part illustrating a lifting step of the main cable.

FIG. 7 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1 ... Main tower steel frame 2 ... Main girder steel frame 5 ... Lifting machine 7 ... Main cable 13 ... Hanger cable

Claims (1)

(57) [Claims] After a main girder steel frame is erected between main tower steel frames, a main cable is deployed on the main girder steel frame, a hanger cable is attached to the main cable, and then the main cable is connected to the main girder by a crane. A method of erection of a cable, wherein the cable is lifted to the top of a steel frame.