Pole reinforcement method

Abstract

The purpose of the present invention is to provide a pole reinforcement method capable of restoring the strength of a hollow metal pole while ensuring safety and reducing time and cost.　A pole reinforcement method according to the present invention is a method for reinforcing a pole 10 in a state where a cable 20 is suspended on the pole 10 that is metal and hollow. The pole reinforcement method is characterized by comprising: holding, with a heavy machine 50 or the like, a pole upper part 10u, which is the part above a cutting location Z where the pole 10 is to be cut (step S01); cutting the pole 10 at the cutting location Z (step S02); moving the pole upper part 10u within a movable range of the cable 20 to reveal a cut opening C of a pole lower part 10l, which is the part below the cutting location Z (step S03); inserting a reinforcement member 35 into the cut opening C of the pole lower part 10l (step S14); and moving the pole upper part 10u to the original position to connect the cut opening C of the pole lower part 10l and the lower end of the pole upper part 10u via the reinforcement member 35 (step S15).

Description

Pole reinforcement method

[0001] The present disclosure relates to a method for restoring strength to a hollow metal pole on which a wire such as a cable is installed.

[0002] FIG. 1 is a diagram illustrating a pole 10 on which a wire object such as a cable 20 is installed. In FIG. 1, GL is the ground surface. Such a pole 10 may have reduced strength due to deterioration X, such as deterioration, damage, or corrosion, at the bottom of the pole near the ground surface GL. If the pole 10 is made of concrete, the strength of the pole can be restored with the wire object still installed using the method described in Non-Patent Document 1.

[0003] "Establishment of Utility Pole Reinforcement Technology Without Excavation at Ground Level," NTT R&D Times, No. 43 (February 2005), https: / / www.rd.ntt / as / times / 043 / 01 / index.html (accessed June 16, 2023)

[0004] However, the method of Non-Patent Document 1 requires workers to work at high altitudes, and ensuring safety has been an issue.

[0005] Furthermore, when the pole 10 is made of hollow metal, the method of Non-Patent Document 1 cannot be adopted, and when a deteriorated portion X occurs in the pole, the pole is often replaced by rebuilding. Replacing a pole by rebuilding requires many construction operations, such as: (1) the process of repairing the excavated hole associated with pole reconstruction (backfilling with soil, compacting, restoring the road surface, etc.), and (2) the process of moving the wire object to the pole after reconstruction. In other words, there is a problem that when a deteriorated portion X occurs in a hollow metal pole, it takes time and costs to deal with it.

[0006] Therefore, in order to solve the above problems, the present invention aims to provide a pole reinforcement method that can restore the strength of hollow metal poles while ensuring safety and reducing time and costs.

[0007] In order to achieve the above object, the pole reinforcing method according to the present invention involves cutting a hollow metal pole and reconnecting the cut portion with a reinforcing member.

[0008] Specifically, the pole reinforcing method of the present invention is a method for reinforcing a metal hollow pole having a cable strung across it, and is characterized by: holding the upper part of the pole, which is above the cutting point where the pole will be cut; cutting the pole at the cutting point; moving the upper part of the pole within the movable range of the cable to reveal a cut opening in the lower part of the pole, which is below the cutting point; inserting a reinforcing member into the cut opening in the lower part of the pole; and moving the upper part of the pole to its original position and connecting the cut opening in the lower part of the pole and the lower end of the upper part of the pole via the reinforcing member.

[0009] This method involves cutting the portion close to the ground and inserting the reinforcing member through the cut portion, eliminating the need to work at high altitudes and ensuring work safety. Furthermore, this work does not require rebuilding the pole, eliminating the need for steps (1) and (2) described above, reducing the time and cost required to address deterioration. Therefore, the present invention provides a pole reinforcement method that can restore the strength of hollow metal poles while ensuring safety and reducing time and costs.

[0010] In detail, the reinforcing member has a male thread shape with an open head and a hollow neck portion, and the reinforcing member is inserted by inserting the neck portion into the cut opening of the pole lower portion, and the connection via the reinforcing member is made by inserting the lower end of the pole upper portion into the head of the reinforcing member. Therefore, a liquid fixing material that fixes the pole lower portion and the reinforcing member can be injected from the head of the reinforcing member to fix them together.

[0011] Here, in order to reduce the amount of fixing material used, it is preferable that the neck portion of the reinforcing member has a partition plate that separates the cavity at any position in the central axis direction, and a window opened on the side of the neck portion, closer to the head side than the partition plate.

[0012] The above inventions can be combined as much as possible.

[0013] The present invention can provide a pole reinforcement method that can restore the strength of hollow metal poles while ensuring safety and reducing time and costs.

[0014] FIG. 1 is a diagram illustrating a pole on which a wire object is installed. FIG. 2 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 3 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 4 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 5 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 6 is a diagram illustrating a pole shape. FIG. 7 is a diagram illustrating a shape of a reinforcing member used in the pole reinforcing method according to the present invention. FIG. 8 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 9 is a diagram illustrating a pole reinforcing method according to the present invention. FIG. 10 is a diagram illustrating a pole reinforcing method according to the present invention.

[0015] The following description of the preferred embodiments of the present invention will be given with reference to the accompanying drawings. The preferred embodiments described below are examples of the present invention, and the present invention is not limited to the preferred embodiments. In this specification and the drawings, components having the same reference numerals are intended to represent the same components.

[0016] 2 to 5 are diagrams illustrating the steps of a pole reinforcement method according to this embodiment. This pole reinforcement method reinforces a hollow, metal pole 10 with a cable 20 strung across it, and includes the steps of: holding an upper pole portion 10u above a cutting point Z where the pole 10 will be cut, using heavy machinery 50 or the like (Step S01); cutting the pole 10 at the cutting point Z (Step S02); moving the upper pole portion 10u within the movable range of the cable 10 to reveal a cutting opening C in a lower pole portion 10l below the cutting point Z (Step S03); inserting a reinforcing member 30 into the hollow portion of the lower pole portion 10l through the cutting opening C (Step S04); and covering the lower end of the upper pole portion 10u with a protruding portion 30a, which is a part of the reinforcing member 30 protruding from the cutting opening C in the lower pole portion 10l (Step S05).

[0017] This will be explained in more detail. [Step S01] Support the upper part of the pole 10 with heavy equipment 50 or the like ( FIG. 2 ). [Step S02] While the upper part of the pole 10 is supported with heavy equipment 50 or the like, cut the lower part of the pole 10 at the cut section Z. In this step, the pole 10 is divided into an "upper pole part 10u" and a "lower pole part 10l" ( FIG. 2 ). [Step S03] Retract the upper pole part 10u with the cable 20 still attached ( FIG. 3 ). This step reveals a cut opening C, which is the cut section Z of the lower pole part 10l. [Step S04] Insert the reinforcing member 30 through the cut opening C of the lower pole part 10l ( FIG. 4 ). Then, fill the gap between the lower pole part 10l and the reinforcing member 30 with cement or the like to secure the lower pole part 10l and the reinforcing member 30 together. [Step S05] With the cable 20 attached to the pole upper part 10u, the lower end of the pole upper part 10u is moved above the reinforcing member 30 (above the cut opening C of the pole lower part 10l) (FIG. 4).The pole upper part 10u is then inserted into the upper part (protruding part 30a) of the reinforcing member 30 and fixed therein (FIG. 5).

[0018] The reinforcing member 30 is introduced into the hollow metal pole 10 to reinforce it, so that the strength loss due to the deteriorated portion X in the lower part of the pole can be restored. In this case, steps (1) and (2) (see above) of the conventional pole replacement renovation can be eliminated, thereby reducing time and costs.

[0019] FIG. 6 is a diagram illustrating the shape of the pole 10. The pole 10 has a truncated cone shape in which the outer and inner diameters decrease from bottom to top. FIG. 7 is a diagram illustrating the shape of the reinforcing member 30. The reinforcing member 30 has a tapered shape in which the protruding portion 30a fits into the hollow of the pole upper portion 10u. The reinforcing member 30 is composed of a straight pipe portion and a tapered portion (protruding portion 30a). The reinforcing member 30 may also be hollow. As shown in FIG. 6, since the pole 10 has a truncated cone shape, the diameter of the straight pipe portion is equal to or smaller than the inner diameter of the cut end C. The tapered portion is shaped to fit into the lower end of the pole upper portion 10u that is to be placed over it. The tapered portion fits into the lower end of the pole upper portion 10u, fixing the pole upper portion 10u to the pole lower portion 10l.

[0020] 8 to 11 are diagrams illustrating the steps of a pole reinforcement method according to this embodiment. This pole reinforcement method reinforces a hollow metal pole 10 having a cable 20 strung across it, and includes the steps of: holding an upper pole portion 10u above a cutting point Z where the pole 10 will be cut, using heavy machinery 50 or the like (Step S01); cutting the pole 10 at the cutting point Z (Step S02); moving the upper pole portion 10u within the movable range of the cable 20 to reveal a cutting opening C in a lower pole portion 10l below the cutting point Z (Step S03); inserting a reinforcing member 35 into the cutting opening C in the lower pole portion 10l (Step S14); and moving the upper pole portion 10u to its original position and connecting the cutting opening C in the lower pole portion 10l to the lower end of the upper pole portion 10u via the reinforcing member 35 (Step S15).

[0021] A more detailed description will be given. Steps S01 to S03 are the same as those described in the first embodiment. [Step S01] This step is shown in FIG. 8 and is the same as step S01 described in the first embodiment. [Step S02] This step is shown in FIG. 8 and is the same as step S02 described in the first embodiment. [Step S03] This step is shown in FIG. 9 and is the same as step S03 described in the first embodiment. [Step S14] The reinforcing member 35 is inserted from the cut opening C of the pole lower portion 10l (step S14a in FIG. 9). The reinforcing member 35 of this embodiment has a male-screw structure with an open head 35a and a hollow neck 35b extending to the tip. Inserting the reinforcing member 35 means inserting the neck 35b into the cut opening C of the pole lower portion 10l. Then, a fixing material 37 such as mortar is poured into the head 35a of the reinforcing member 35 and filled to fix the pole lower portion 10l and the reinforcing member 35 together (step S14b in FIG. 10). [Step S15] With the cable 20 attached to the pole upper portion 10u, the lower end of the pole upper portion 10u is moved above the reinforcing member 30 (above the cut opening C of the pole lower portion 10l) (step S15a in FIG. 10). Then, the pole upper portion 10u is inserted into the head portion 35a of the reinforcing member 35 (step S15b in FIG. 11). In this embodiment, the connection via the reinforcing member is achieved by inserting the lower end of the pole upper portion 10u into the head portion 35a of the reinforcing member 35. [Step S16] Finally, a fixing material 37 such as mortar that fixes the pole upper portion 10u to the reinforcing member 35 is injected through the gap between the head portion 35a of the reinforcing member 35 and the lower end of the pole upper portion 10u, thereby fixing the pole upper portion 10u to the reinforcing member 35 (step S16 in FIG. 11).

[0022] The reinforcement member 35 is introduced into the deteriorated portion X of the hollow metal pole 10 to reinforce it, thereby recovering the strength loss caused by the deteriorated portion X of the pole. In this case, steps (1) and (2) (see above) of the conventional pole replacement renovation are not required, thereby reducing time and costs.

[0023] 12A and 12B are diagrams illustrating the structure of the reinforcing member 35. Fig. 12A is an external view of the reinforcing member 35, and Fig. 12B is a cross-sectional view illustrating the interior of the reinforcing member 35. The reinforcing member 35 has a male-screw-like structure in which the head 35a is open and the head 35a is hollow up to the tip of the neck 35b. The neck 35b has a partition plate 35d that separates the hollow at an arbitrary position T in the central axis direction, and a window 35c that is opened in a side surface of the neck 35b, closer to the head 35a than the partition plate 35d.

[0024] The window 35c has the following function: when the fixing material 37 is injected from the head 35a, the fixing material 37 flows outward from the window 35c, and the space in the neck portion 35b beyond the position T is not filled with the fixing material 37. In other words, the window 35c can reduce the amount of fixing material 37 used by the amount corresponding to the space in the neck portion 35b beyond the position T.

[0025] Although the partition plate 35d is shown as a flat disk in FIG. 12, it may be shaped like a truncated cone so that the fixing material 37 can flow out smoothly from the window 35c.

[0026] In the case of the reinforcing member 30 of the first embodiment, a manufacturing error in the inner diameter of the pole upper portion 10u may make it difficult to fit the pole upper portion 10u and the pole lower portion 10l together, making it impossible to connect them. On the other hand, in the case of the reinforcing member 35 of the second embodiment, the lower end of the pole upper portion 10u is simply inserted into the head portion 35a, so that the pole upper portion 10u and the pole lower portion 10l can be connected together even if there is a manufacturing error in the inner diameter of the pole upper portion 10u.

[0027] 10: Pole 10u: Upper part of pole 10l: Lower part of pole 20: Cable 30: Reinforcing member 30a: Protruding part 35: Reinforcing member 35a: Head part 35b: Lower part of neck 37: Fixing material 50: Heavy machinery

Claims

1. A method of reinforcing a hollow metal pole with a cable strung across it, comprising: holding an upper part of the pole that is above a cutting point; cutting the pole at the cutting point; moving the upper part of the pole within the movable range of the cable to reveal a cut opening in the lower part of the pole that is below the cutting point; inserting a reinforcing member into the cut opening in the lower part of the pole; and moving the upper part of the pole to its original position and connecting the cut opening in the lower part of the pole with the lower end of the upper part of the pole via the reinforcing member.

2. The pole reinforcing method according to claim 1, characterized in that the reinforcing member is a male thread with an open head and a hollow neck portion extending to the tip, the reinforcing member is inserted by inserting the neck portion into the cut opening of the pole lower portion, and the connection via the reinforcing member is made by inserting the lower end of the pole upper portion into the head of the reinforcing member.

3. A pole reinforcing method according to claim 2, characterized in that a liquid fixing material that fixes the lower part of the pole and the reinforcing member is poured from the head of the reinforcing member.

4. A threaded reinforcing member with an open head and a hollow neck down to the tip.

5. A reinforcing member as described in claim 4, characterized in that the neck portion has a partition plate that separates the cavity at an arbitrary position in the central axis direction, and a window opened on the side of the neck portion, closer to the head portion than the partition plate.

Images