JPH0320550B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] In recent years, with the increasing density in urban areas, power transmission towers are being constructed in close proximity to existing power transmission lines. Due to the insufficient separation distance between the lines, it becomes necessary to relocate the power transmission lines to a higher position.

The present invention relates to a construction method for increasing the tower height and raising the height of the steel tower under such circumstances.

[Prior art and problems] Conventionally, this type of raising construction method involves installing a beam on a frame structure outside the steel tower and raising the upper beam that supports the upper steel tower with a cylinder, or installing it inside the frame structure. There is a construction method in which the upper part of the steel tower is placed on a lifting platform, raised from below, and the lower part of the steel tower is attached below it (Special Publication No. 32526, 1983).
Special Publication No. 48-26614).

However, these construction methods require a large work site, especially since the framework structure is installed outside the tower, and it is impossible to carry out the raising work in narrow spaces where such land is not available or in cases where it is difficult to secure land. There was a certain drawback.

In addition, since it takes time to assemble the framework, there may be long power outages due to the raising work.
The disadvantage was that it required the construction of a temporary tower for bypass power transmission.

[Means for solving problems]

The present invention solves the above-mentioned drawbacks, and its means are to raise the ground wire along the tower core to the top while sequentially connecting the unit steel pipes using an upper pulley rope attached to the top of the tower body of the existing steel tower. The single-column steel pipe tower, which is constructed by connecting a predetermined number of unit steel pipes, will be temporarily relocated to the arm at the top and raised further from the top to a predetermined height using a lower pulley rope, etc. attached below, and the lowest part of the single-column steel pipe tower will be raised from the top to a predetermined height. The lower end of the unit steel pipe connected to the tower is fixed to the foundation concrete, and after raising the height of the tower, the single-column steel pipe tower is fixedly supported by the opposing side members of the tower, the ground wire is relocated to the single-column steel pipe tower, and an arm is attached. The electric wires from the old arm of the steel tower will be transferred to the arm, and the old arm and the tower body of the old arm portion will be dismantled and removed, and the raised single-column steel pipe tower will be used as the raised steel tower.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is an existing steel tower, and a single column steel pipe tower 2 will be constructed within this steel tower 1.

This single-column steel pipe tower 2 is assembled by the following construction method.

(a) As shown in FIG. 2, the upper pulley 3 is suspended from the top of the tower body of the steel tower 1, and the opposing sap material that gets in the way of work inside the steel tower 1 is removed.

(b) The upper wire rope 5 let out from the winding drum of the upper hoist 4 installed on the ground is hung around the above-mentioned upper pulley 3 via the guide pulley and suspended inside the steel tower 1.

(c) Deliver the required number of unit steel pipes 2a of a predetermined length to the ground within the steel tower 1.

(d) Install guide mechanisms 6 at a location approximately 1/3 below the tower height from the top of the steel tower 1 and where the horizontal member 1a is located, and at a similar location approximately 1/3 above the tower height from the ground. Install.

As shown in FIG. 6, this guide mechanism 6 connects the other ends of four support wire ropes 6c fastened to a frame 6b having a plurality of guide rollers 6a so that the guide rollers 6a are located at the center of the steel tower 1. Fasten it to the four corners of the horizontal member 1a.

(e) Tie the upper end of the carried-in unit steel pipe 2a to the hanging end of the upper wire rope 5, operate the upper hoisting machine 4 to lift the unit steel pipe 2a, and flange-join the next unit steel pipe 2a below it. While passing through the guide roller 6a, the rope is successively connected and lifted up to the winding limit of the upper wire rope 5 (near the top of the tower body).

(f) As shown in Figure 3, two lower pulleys 7 are suspended diagonally from the horizontal member 1a at an appropriate height (approximately 10 m) above the ground of the steel tower 1, and two pulleys are installed on the ground. A single-column steel pipe tower 2 in which the predetermined number of unit steel pipes 2a are connected from the winding drum of the lower winding machine 8.
A lower wire rope 9 is let out to raise the lower wire rope 9, and is hung around the lower pulley 7 via a guide pulley and suspended inside the steel tower 1.

(g) Attach a temporary arm 10 to the arm 1b at the top of the tower body, temporarily relocate the ground wire 11 at the top of the tower to this temporary arm 10, and dismantle and remove the tower top.

(h) Hook the hooks at each end of the lower wire rope 9 to the lower part of the unit steel pipe 2a at the bottom of the single-column steel pipe tower 2 (at this time, remove the upper pulley 3), and operate the lower hoist 8 to Raise the column steel pipe 2 upward from the top of the tower.

(i) Single-column steel pipe tower 2 shall be used to raise the tower to the specified height.
The necessary number of unit steel pipes 2a are added to the lowest end of the unit steel pipe 2a, and the unit steel pipes 2a are fixed to anchor bolts of the foundation concrete 15 cast in advance on the ground.

(j) As shown in Fig. 4, opposite sill members 1c are attached to required locations on the steel tower 1, and the single-column steel pipe tower 2 is fixed to this opposite sill member 1c so as to be located at the tower core.

(k) Relocate the ground wire 11 to the top of the single-column steel pipe tower 2.

(l) Stop the power transmission line on one side, attach each arm 12, 13, and 14 on one side to the single-column steel pipe tower 2, and transfer the electric wires of the old arm to it.

The old arm will be dismantled and removed, and the one-sided power transmission line will be restored.

(m) Perform the same work as in (l) above for the other side's power transmission line.

(n) The tower bodies of the old arms of both transmission lines will be dismantled and removed.

Through the above steps, the raised steel tower shown in FIG. 5 is completed.

〔effect〕

(a) Existing steel towers can be raised safely and quickly within the site.

(b) The tower-shaped steel tower section surrounds the lower part of the lowest arm of the single-column steel pipe tower, and the single-column steel pipe tower is fixedly supported by the opposing sap, so the tower-shaped steel tower section shares the horizontal load. , the single-column steel pipe tower only needs to share the vertical load, and therefore its outer diameter can be small, making it economical.

(c) Since the arm is attached to a small-diameter single-column steel pipe tower, its overhang width can be made smaller than the arm overhang width of the old steel tower section, and less land is needed under the electric wires.

(d) Since turbulence in relation to the wind direction occurs in the tower-shaped steel tower section, rectification is difficult to occur in the single-column steel pipe tower, and the occurrence of vibration can therefore be suppressed.

In addition, in the present invention, the method of raising the height of an existing steel tower has been explained, but as mentioned above, the lower half of a single-column steel pipe tower fixed to the foundation concrete is surrounded by a tower-shaped steel tower, and the steel pipe tower is Supported by opposing saplings, the single-column steel pipe tower takes the vertical load, and the tower-shaped steel tower takes the horizontal load.
It is also possible to apply this to the configuration when constructing a new power transmission tower.

[Brief explanation of the drawing]

Figure 1 is a front view of the existing steel tower, Figures 2 to 4 are explanatory diagrams of an embodiment of the raising method according to the present invention, Figure 5 is a front view after the raising is completed, and Figure 6 is the guide mechanism. FIG. 1...Existing steel tower, 2...Single column steel pipe tower, 2a...
Unit steel pipe, 3... Upper pulley, 4... Upper hoist, 5... Upper wire rope, 6... Guide mechanism, 7... Lower pulley, 8... Lower hoist, 9...
... Lower wire rope, 10 ... Temporary arm, 11
...Ground wire, 12,13,14...Arm, 15...
...Foundation concrete.

Claims (1)

[Claims] 1. Raise the unit steel pipes along the tower core to the top while sequentially connecting them using upper pulley ropes etc. attached to the top of the tower body of the existing steel tower. Temporarily relocate the ground wire to the arm at the top of the tower body, and A single-column steel pipe tower made up of connections is raised from the top of the tower to a specified height using a lower pulley rope attached to the bottom of the tower, and the lower end of the unit steel pipe connected to the bottom of the single-column steel pipe tower is fixed to the foundation concrete. After the work to raise the height of the steel tower, the single-column steel pipe tower was fixed and supported by the opposite side members of the steel tower, the ground wire was relocated to the single-column steel pipe tower, an arm was attached, and the electric wires from the old arm of the steel tower were transferred to the arm. , a method of raising the height of a power transmission tower, which is characterized by dismantling and removing the old arm and the tower body of the old arm part.