JP5482216B2 - Steel tower reconstruction method - Google Patents

Description

  The present invention relates to a steel tower rebuilding method for a steel tower rebuilding work.

  Electricity generated at the power station of the electric power company is transmitted over a long distance through a transmission line stretched over a steel tower built on the ground, and after being transformed at the substation, it is supplied to consumers. A steel tower that stretches a transmission line needs to be rebuilt when it becomes obsolete due to aging, etc., or when the height of the steel tower is insufficient to stretch a transmission line that transmits a large amount of electricity. .

  Reconstruction of the steel tower is done by removing the existing steel tower (hereinafter referred to as the existing steel tower) and reconstructing the steel tower (hereinafter referred to as the steel tower rebuilding work) to install a new steel tower (hereinafter referred to as the new steel tower). Done. At this time, the new steel tower is often installed at the same position as the existing steel tower to be removed, i.e., the original position, due to the existence of existing buildings around the existing steel tower and the wiring of the stretched wires. .

  Naturally, it was necessary to remove the existing steel tower before constructing the new steel tower in its original position. However, when the existing steel tower is removed, there is no longer anything that stretches the transmission line, so there will be a situation in which power transmission is interrupted during the construction period and power transmission areas must be interrupted. Therefore, in order to avoid a long-term power outage, a temporary construction for constructing a temporary steel tower that stretches a transmission line instead of the existing steel tower has been performed (temporary construction method).

  FIG. 13 is a diagram for explaining a temporary construction method as a conventional steel tower rebuilding method. In the temporary construction method, first, as shown in FIG. 13 (a), the temporary foundation 20a of the temporary tower 20 is constructed on the land away from the existing tower 10, and the temporary tower 20 is constructed on the temporary foundation 20a (temporary construction). . Then, as shown in FIG. 13 (b), the transmission line 12 stretched around the existing tower 10 is moved to the temporary tower 20. Then, as shown in FIG.13 (c), the existing steel tower 10 and the old foundation 10a of the existing steel tower 10 are removed.

  When the existing steel tower 10 and its old foundation 10a are removed, as shown in FIG. 13 (d), the new foundation 30a of the new steel tower 30 is constructed on the site (original position) where the existing steel tower 10 has been installed. A new tower 30 is constructed on 30a. Then, as shown in FIG. 13 (e), the transmission line 12 stretched around the temporary tower 20 is moved to the new tower 30. Then, as shown in FIG.13 (f), the temporary steel tower 20 and the temporary foundation 20a are removed, and a steel tower rebuilding construction is completed.

  With the temporary construction method described above, the transmission is interrupted only when the transmission line is transferred from the existing tower 10 to the temporary tower 20 and when the transmission line is transferred from the temporary tower 20 to the new tower 30. Usually, of the two routes of transmission lines, it will be relocated due to a power outage on one route, so the burden on the customer is small. However, when this temporary construction method is carried out, not only the landowner of the land for the construction of the temporary tower 20 obtains the agreement, but also the landowner of the land under the transmission line 12 moved to the temporary tower 20. It was necessary to obtain the consent of the contract, and complicated procedures were required for the contract.

  Moreover, when the power transmission line 12 is moved to the temporary tower 20 in the temporary construction method, the load applied to the steel towers before and after (on both sides of the temporary tower 20) increases. Then, since the strength of such a steel tower is insufficient, it is necessary to reinforce the steel tower and the foundation, and there is a problem that the construction period is prolonged and the cost is increased.

  Furthermore, when the transmission line 12 to be relocated to the temporary tower 20 is an ultra-high-voltage transmission line (extra-high voltage overhead electric wire) that transmits electricity having a voltage of 170 kV or higher, and there is an existing building within a predetermined range from the transmission line 12 There is a restriction by law that the transmission line 12 cannot be laid. In the case of mountainous areas, etc., there are some buildings that do not have buildings, so such restrictions are not a problem. However, in urban areas where buildings are densely populated, it may be difficult to secure land. . In addition, the temporary construction method requires construction of one steel tower even though it is a temporary construction, so it takes a lot of time and money to construct and remove the temporary steel tower 20, leading to a long construction period and an increase in cost. There was also a problem.

  For the above reasons, in recent years, the wrapping method has gradually become widespread instead of the temporary work method. For example, in Patent Document 1, a support structure longer than a brace is attached to an existing steel tower, and a power transmission line is supported by the support structure via a jumper line, and then the new steel tower is wrapped. A method for rebuilding a steel tower for constructing a steel tower is disclosed.

  FIG. 14 is a diagram for explaining a wrapping method as a conventional steel tower rebuilding method. The general wrapping method will be described in more detail. First, the new foundation 50a of the new tower 50 as shown in FIG. 14 (b) at a position shifted from the old foundation 40a of the existing tower 40 shown in FIG. 14 (a). Install. And as shown in FIG.14 (c), the new steel tower 50 is constructed on the new foundation 50a so that the existing steel tower 40 may be wrapped, and it is stretched by the existing steel tower 40 as shown in FIG.14 (d). The power transmission line 42 is moved to the new steel tower 50. Thereafter, the existing tower 40 is removed as shown in FIG. 14 (e) to complete the tower rebuilding work, and the new tower 50 shown in FIG. 14 (f) is completed.

  According to the wrapping method described above, the steel tower can be rebuilt without constructing the temporary tower 20, and therefore, when the transmission line 12 is moved to the construction site of the temporary tower 20 or the temporary tower 20, It eliminates the need for contracting land under the line, and reduces complicated procedures. In addition, the cost required for the temporary steel tower 20 can be reduced, and the work period can be shortened.

JP 2001-112131 A

  According to the wrapping method described above, it was possible to perform the steel tower rebuilding work more efficiently than the temporary construction method. However, referring again to FIG. 14, the new tower 50 itself is contained within the site of the existing tower 40 (hereinafter referred to as the existing site), but the new foundation 50 a provided in the construction of the new tower 50 is outside the existing site. It extends to.

  If the new foundation 50a is installed only temporarily like the temporary tower 20, the land around the existing site may be leased only during the construction period, but the new tower 50 will be used permanently until the next rebuilding. Therefore, the new foundation 50a is also permanently installed in the same manner. For this reason, when the components of the new steel tower 50 extend beyond the existing site as in the case of the enclosing method, the surrounding land where the new foundation 50a protrudes must be purchased or leased as long as the steel tower exists. .

  However, there are many landowners who allow temporary lease land but do not permit sale or semi-permanent lease land, and it is difficult to negotiate for purchase. Also, since the purchase and sale of land is more complicated than the lease of land, the procedure becomes more complicated when buying more land. Furthermore, if there are no existing buildings around the existing site, it is possible to buy more and negotiate, but in areas where there are dense buildings such as urban areas, existing buildings are installed on the land around the existing site. There are many. In this case, there is no room for additional purchase negotiations.

  Therefore, the enveloping method has a problem that it cannot be applied when the new foundation does not fit in the existing site and the land around the existing site cannot be purchased or semipermanently leased. For this reason, even if it is a case where an enveloping method cannot be applied, development of the tower rebuilding method which can perform a tower rebuilding work efficiently is calculated | required.

  In view of such a problem, the present invention can efficiently perform the steel tower rebuilding work even when it is impossible to purchase additional land, and can shorten the construction period and reduce the construction cost. The purpose is to provide a steel tower rebuilding method.

  In order to solve the above problems, the typical structure of the tower reconstruction method according to the present invention is to remove the existing tower over which the transmission line is stretched, and to install the new tower at the position where the existing tower was installed. This is a steel tower rebuilding method used for the steel tower rebuilding work, in which a temporary foundation is constructed around or inside the old foundation, which is the foundation of the existing steel tower, and the lower part of the temporary steel tower is constructed on the temporary foundation. Support the upper part of the tower, remove the lower part of the existing tower and the old foundation of the existing tower, construct the new foundation at the position where the old foundation of the existing tower was installed, and surround the upper part of the existing tower on the new foundation As described above, the new steel tower is constructed, the transmission line is transferred from the existing steel tower to the new steel tower, and the upper part of the existing steel tower and the lower part of the temporary steel tower are removed.

  According to the said structure, the new foundation of a new steel tower can be constructed in the same position as the old foundation of an existing steel tower by temporarily supporting the existing steel tower upper part by a temporary steel tower lower part. Thereby, even if it is not possible to purchase more land, the steel tower rebuilding work can be performed efficiently, and the construction period can be shortened and the construction cost can be reduced.

  In order to solve the above-mentioned problem, another structure of the steel tower rebuilding method according to the present invention is to remove an existing steel tower that stretches a transmission line and to install a new steel tower at a position where the existing steel tower was installed. It is a steel tower rebuilding method used for steel tower rebuilding work, in which a temporary foundation is constructed around or inside the old foundation that is the foundation of the existing steel tower, a temporary steel tower lower part is constructed on the temporary foundation, and an existing steel tower is installed on the lower part of the temporary steel tower. The upper part of the new steel tower was constructed to surround the upper part of the steel tower, the transmission line was transferred from the existing steel tower to the new steel tower, the existing steel tower and the old foundation of the existing steel tower were removed, and the old foundation of the existing steel tower was provided A new foundation is constructed at the location, the lower part of the new tower is built inside the lower part of the temporary tower, the upper part of the new tower is supported by the lower part of the new tower, and the lower part of the temporary tower is removed .

  According to the said structure, the new foundation of a new steel tower can be constructed in the same position as the old foundation of an existing steel tower by temporarily supporting the upper part of a new steel tower by the temporary steel tower lower part. Thereby, even if it is not possible to purchase more land, the steel tower rebuilding work can be performed efficiently, and the construction period can be shortened and the construction cost can be reduced.

  In the case of the above-mentioned multiple steel tower rebuilding methods, even if the area around the extra high voltage overhead cableway of 170 kV or higher is urbanized and it is impossible to construct a temporary tower and relocate the transmission line, As long as the land can be temporarily leased, it can be rebuilt without violating the technical standards for electrical equipment. Moreover, in this steel tower rebuilding method, the electric wire transfer from the existing steel tower to the new steel tower is such that the moving direction of the transmission line is the vertical direction (moving from below to above). For this reason, the load added to the steel tower before and behind the steel tower used as rebuilding object does not increase. This eliminates the need to reinforce the front and rear steel towers and their foundations, thereby solving the problems of longer construction period and cost.

  The temporary foundation described above may be constructed by hitting two or more piles along any two opposing sides of the four sides of the quadrangle whose apex is the old foundation of the existing steel tower. According to such a configuration, when the existing steel tower is viewed from above, among the four sides of the quadrangle whose apex is the old foundation, any two opposing sides, that is, along the upper side and the lower side, or on the left side and the right side Two or more temporary foundations are constructed along. Accordingly, the temporary foundation and the lower part of the temporary tower extend only to one of the land around the existing site, the land adjacent to the upper side and the lower side, or the land adjacent to the left side and the right side. For this reason, it becomes possible to select the positions of the temporary foundation and the lower part of the temporary tower, and even if there are existing buildings on two opposite sides around the existing tower, the advantage that the tower rebuilding work can be performed efficiently There is.

  The temporary foundation described above may be constructed by hitting two or more piles along all four sides of the quadrangle with the old foundation of the existing steel tower as the apex. According to such a configuration, the lower part of the temporary tower is constructed on eight or more temporary foundations provided along the four sides of a quadrangle whose apex is the old foundation of the existing tower. Therefore, since the number of temporary foundations is large, the load applied to one temporary foundation can be reduced, and the stability of the lower part of the temporary steel tower can be improved.

  Said temporary foundation is good to be constructed in the approximate middle point of each of the four sides of the quadrangle with the old foundation of the existing steel tower as the apex. According to such a configuration, the temporary foundation and the lower portion of the temporary steel tower constructed on the temporary foundation are provided in the area of the existing steel tower. Therefore, since they do not extend outside the existing site, it is not necessary to rent the land around the existing site. In addition, since the temporary foundation is provided at approximately the midpoint of each of the four sides of the quadrangle with the old foundation of the existing tower as a vertex, the vertical framework of the lower part of the temporary tower constructed on the temporary foundation is The frame in the vertical direction is disposed at a position rotated approximately 45 °. For this reason, the interference between the lower part of the existing steel tower and the lower part of the temporary steel tower is mitigated, and it becomes possible to improve the working efficiency.

  Said temporary foundation is good to be constructed on the diagonal inside the square which makes the old foundation of an existing steel tower a vertex. According to such a configuration, the temporary foundation and the lower part of the temporary steel tower constructed on the temporary foundation do not interfere with the lower part of the existing steel tower or the lower part of the new steel tower because the lower part of the temporary steel tower is built inside the existing steel tower. Thereby, the temporary steel tower lower part does not interfere with the construction of the lower part of the existing steel tower or the lower part of the new steel tower, and the work efficiency can be increased.

  According to the present invention, there is provided a steel tower rebuilding method capable of efficiently performing steel tower rebuilding work even when it is impossible to purchase additional land, and shortening the construction period and reducing the construction cost. Can be provided.

It is the schematic explaining the steel tower rebuilding method concerning 1st Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 1st Embodiment. It is a flowchart explaining the steel tower rebuilding method concerning 1st Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 2nd Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 2nd Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 3rd Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 3rd Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 4th Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 4th Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 5th Embodiment. It is the schematic explaining the steel tower rebuilding method concerning 5th Embodiment. It is a flowchart explaining the steel tower rebuilding method concerning 5th Embodiment. It is a figure explaining the temporary construction method as a conventional steel tower rebuilding method. It is a figure explaining the wrapping construction method as the conventional steel tower rebuilding method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  In the schematic diagram used in the description of the embodiment, the existing steel tower and the old foundation are indicated by a solid line, the temporary iron tower and the temporary foundation are indicated by an alternate long and short dash line, the new iron tower and the new foundation are indicated by a thick solid line, and a portion to be removed is indicated by a broken line. In the schematic diagrams, (a), (c), (e), and (g) are schematic diagrams of the side surface of the steel tower, and (b), (d), (f), and (h) are schematic diagrams of the top surface of the steel tower.

(First embodiment)
1 and 2 are schematic diagrams for explaining the steel tower rebuilding method according to the first embodiment, and FIG. 3 is a flowchart for explaining the steel tower rebuilding method according to the first embodiment. In the steel tower rebuilding method according to the first embodiment, the root opening of the existing steel tower is expanded by the lower part of the temporary steel tower (hereinafter referred to as the existing widening root opening).

  When rebuilding the existing steel tower 110 by the steel tower rebuilding method according to the first embodiment, first, the temporary foundation 122 is constructed around the old foundation 112 that is the foundation of the existing steel tower 110 as shown in FIG. 1A (step S172). ). Thereby, the temporary foundation 122 is provided around the existing site 102 as shown in FIG. In the present embodiment, the temporary foundation 122 is constructed by hitting two piles along any two opposing sides of the four sides of the quadrangle having the old foundation 112 of the existing tower 110 as a vertex. That is, when the existing steel tower 110 is viewed from above as shown in FIG. 1B, any two opposing sides (in the present embodiment, the left side and the left side) of the four sides of the quadrangle having the old foundation 112 as a vertex. Two temporary foundations 122 are constructed along the right side).

  According to the above configuration, the temporary foundation 122 and the temporary steel tower lower part 120 constructed on the temporary foundation 122 are either the land adjacent to the upper side and the lower side or the land adjacent to the left side and the right side of the land around the existing site 102. Only on one land. For this reason, there exists an advantage that the position of the temporary foundation 122 and the temporary steel tower lower part 120 can be selected in the case where there are existing buildings on two opposite sides around the steel tower.

  In the present embodiment, the temporary foundation 122 is provided on the land adjacent to the left side and the right side of the land around the existing site 102. However, the present invention is not limited to this, and is provided on the land adjacent to the upper side and the lower side. May be. It is preferable to determine which side is provided in consideration of the dominant load of the existing tower 110. In this embodiment, two temporary foundations 122 are provided on one side, but this is not restrictive, and three or more temporary foundations may be provided.

  Next, as shown in FIG.1 (c), the temporary steel tower lower part 120 is constructed on the temporary foundation 122 so that the lower part of the existing steel tower 110 (henceforth the existing steel tower lower part 110b) may be surrounded (step S174). At this time, since the temporary foundation 122 is constructed around the old foundation 112, that is, around the existing site 102 (see FIG. 1B), the temporary tower lower part 120 is also built around the existing tower lower part 110b, As shown in FIG. 1 (d), the temporary foundation 122 and the temporary steel tower lower portion 120 extend outside the existing site 102. However, as will be described later, since the temporary foundation 122 and the lower part of the temporary tower 120 are finally removed, there is no need to purchase additional land around the existing site 102, and it is only necessary to rent the land temporarily. Reconstruction work can be performed.

  When the temporary steel tower lower part 120 is constructed, the existing steel tower 110 and the temporary steel tower lower part 120 are connected, and the upper part of the existing steel tower 110 (hereinafter referred to as the existing steel tower upper part 110a) is supported by the temporary steel tower lower part 120 (step S176). Thereafter, the existing steel tower lower portion 110b is removed as shown in FIGS. 1E and 1F (step S178), and then the old foundation 112 is removed as shown in FIGS. 1G and 1H (step S180). ).

  If the existing steel tower lower part 110b and the old foundation 112 are removed, the new foundation 132 will be constructed in the position where the old foundation 112 was provided as shown to Fig.2 (a) (step S182). And as shown in FIG.2 (c), the new steel tower 130 is constructed on the new foundation 132 so that the existing steel tower upper part 110a may be surrounded (step S184). At this time, as shown in FIG. 2 (b), the new foundation 132 is provided in the position where the old foundation 112 was provided, that is, in the existing site 102. Therefore, the new tower 130 is also installed as shown in FIG. 2 (d). It will be built on the site.

  When the new steel tower 130 is constructed, the transmission line 104 is moved from the existing steel tower 110 to the new steel tower 130 (step S186). Then, as shown in FIGS. 2E and 2F, the existing steel tower upper part 110a is removed (step S188), the temporary steel tower lower part 120 is removed (step S190), and the temporary foundation 122 is land around the existing site 102. (Step S192). Thereby, as shown to FIG.2 (g) and (h), the new steel tower 130 is completed and the said steel tower rebuilding construction is completed.

  As described above, according to the steel tower rebuilding method according to the first embodiment, the temporary steel tower lower part 120 is used to temporarily support the existing steel tower upper part 110a, thereby the same position as the old foundation 112 of the existing steel tower 110. The new foundation 132 of the new steel tower 130 can be constructed. As a result, it is possible to construct the new steel tower 130 at the same position as the existing steel tower 110, and it is possible to efficiently perform the steel tower rebuilding work even if it is not possible to purchase additional land. Therefore, the construction period can be shortened and the construction cost can be reduced. Since only the temporary foundation 122 and the lower part of the temporary tower 120 are temporarily installed during the rebuilding work, the cost and time required for the construction and removal of the upper part of the temporary tower can be reduced. Can be achieved.

(Second Embodiment)
The steel tower rebuilding method according to the second embodiment is an existing enlarged root opening as in the first embodiment, but the piles are struck along all four sides of the quadrangle with the old foundation 112 as a vertex. It differs from the first embodiment in that the foundation 122 is constructed.

  4 and 5 are schematic diagrams for explaining the steel tower rebuilding method according to the second embodiment. In addition, since the procedure of the steel tower rebuilding method of 2nd Embodiment is the same as that of the steel tower rebuilding method of 1st Embodiment, refer FIG. 3 for a flowchart. Moreover, about the element which has the function and structure substantially the same as the component of the steel tower rebuilding method of 1st Embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  When rebuilding the existing steel tower 110 by the steel tower rebuilding method according to the second embodiment, first, the temporary foundation 122 is constructed around the old foundation 112 that is the foundation of the existing steel tower 110 as shown in FIG. 4A (step S172). ). Thereby, the temporary foundation 122 is provided around the existing site 102 as shown in FIG.

  In this embodiment, the temporary foundation 122 is constructed by hitting two piles along all four sides of a quadrangle having the old foundation 112 of the existing tower 110 as a vertex. Therefore, since the load applied to the temporary foundation 122 around one is reduced, the stability of the temporary steel tower lower portion 220 is improved. In the present embodiment, two temporary foundations 122 are provided on one side, but the present invention is not limited to this, and three or more temporary foundations may be provided.

  Next, as shown in FIG.4 (c), the temporary iron tower lower part 220 is constructed on the temporary foundation 122 so that the lower part of the existing iron tower 110 may be surrounded (step S174). Also in this embodiment, since the temporary foundation 122 is constructed around the existing site 102 (see FIG. 4B), as shown in FIG. 4D, the temporary steel tower lower part 220 is also a part of the existing steel tower lower part 110b. It extends to the surroundings. However, since the temporary foundation 122 and the temporary steel tower lower part 220 are finally removed, the steel tower rebuilding work can be performed only by temporarily renting the land around the existing site 102.

  When the temporary steel tower lower part 220 is constructed, the existing steel tower 110 and the temporary steel tower lower part 220 are connected, and the existing steel tower upper part 110a is supported by the temporary steel tower lower part 220 (step S176). Thereafter, the existing steel tower lower part 110b is removed as shown in FIGS. 4E and 4F (step S178), and then the old foundation 112 is removed as shown in FIGS. 4G and 4H (step S180). ).

  Then, as shown in FIG. 5 (a), the new foundation 132 is constructed at the position where the old foundation 112 was provided (step S182), and as shown in FIG. 5 (c), the existing steel tower upper part 110a is surrounded. A new steel tower 130 is constructed on the new foundation 132 (step S184). Also in this case, since the new foundation 132 is provided in the existing site 102 as shown in FIG. 5 (b), the new steel tower 130 is also constructed in the existing site as shown in FIG. 5 (d).

  When the new steel tower 130 is constructed, the transmission line 104 is moved from the existing steel tower 110 to the new steel tower 130 (step S186), and as shown in FIGS. 5E and 5F, the existing steel tower upper portion 110a is removed (step S188). ), The temporary steel tower lower part 220 is removed (step S190), and the temporary foundation 122 is removed from the land around the existing site 102 (step S192). Thereby, as shown to FIG.5 (g) and (h), the new steel tower 130 is completed and the said steel tower rebuilding construction is completed.

  As described above, also in the steel tower rebuilding method according to the second embodiment, the existing steel tower upper part 110a is temporarily supported using the temporary steel tower lower part 220, and the new steel tower is located at the same position as the old foundation 112 of the existing steel tower 110. 130 new foundations 132 can be constructed. Therefore, even if it is not possible to purchase additional land, it is possible to efficiently perform the steel tower rebuilding work, and the construction period can be shortened and the construction cost can be reduced.

(Third embodiment)
In the steel tower rebuilding method according to the third embodiment, the number of temporary foundations 122 is the same as that of the first embodiment, but a pile is struck at each of the substantially midpoints of the four sides of the quadrangle with the old foundation 112 as a vertex. It differs from 1st Embodiment in the point which constructs temporary foundation 122 (existing twist and pile between legs).

  6 and 7 are schematic diagrams for explaining the steel tower rebuilding method according to the third embodiment. In addition, since the procedure of the steel tower rebuilding method of 3rd Embodiment is the same as that of the steel tower rebuilding method of 1st Embodiment, refer FIG. 3 for a flowchart. Moreover, about the element which has the function and structure substantially the same as the component of the steel tower rebuilding method of 1st Embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  When rebuilding the existing steel tower 110 by the steel tower rebuilding method according to the third embodiment, first, as shown in FIG. 6 (a), each of the four sides of the quadrangle having the old foundation 112 which is the foundation of the existing steel tower 110 as a vertex. The temporary foundation 122 is constructed at the midpoint (around or inside the old foundation) (step S172). Thereby, the temporary foundation 122 is provided in the existing site 102 as shown in FIG. Therefore, the temporary steel tower lower part 320 constructed on the temporary foundation 122 is provided in the existing site 102 (in the area of the existing steel tower 110). For this reason, both the temporary foundation 122 and the temporary steel tower lower part 320 can be installed without reaching the existing site 102.

  Next, as shown in FIG.6 (c), the temporary steel tower lower part 320 is constructed on the temporary foundation 122 (step S174). In the present embodiment, since the temporary foundation 122 is provided at substantially the midpoint of each of the four sides of the quadrangle made of the old foundation 112 (see FIG. 6B), the temporary steel tower lower part 320 constructed on the temporary foundation 122 is provided. The vertical frame is disposed at a position obtained by rotating the vertical frame of the existing steel tower 110 by approximately 45 °. Thereby, interference with the existing steel tower lower part 110b and the temporary steel tower lower part 320 is relieved, and it becomes possible to aim at the improvement of work efficiency.

  When the temporary steel tower lower part 320 is constructed, the existing steel tower 110 and the temporary steel tower lower part 320 are connected, and the existing steel tower upper part 110a is supported by the temporary steel tower lower part 320 (step S176). Thereafter, the existing steel tower lower part 110b is removed as shown in FIGS. 6E and 6F (step S178), and then the old foundation 112 is removed as shown in FIGS. 6G and 6H (step S180). ).

  Then, as shown in FIG. 7A, the new foundation 132 is constructed at the position where the old foundation 112 was provided (step S182), and as shown in FIG. 7C, the existing steel tower upper part 110a is surrounded. A new steel tower 130 is constructed on the new foundation 132 (step S184). At this time, since the new foundation 132 is provided in the existing site 102 as shown in FIG. 7B, the new tower 130 is also constructed in the existing site 102 as shown in FIG. 7D. Thereafter, the transmission line 104 is moved from the existing steel tower 110 to the new steel tower 130 (step S186), and as shown in FIGS. 7E and 7F, the existing steel tower upper portion 110a is removed (step S188), and the temporary steel tower lower portion is removed. 320 is removed (step S190).

  If the existing steel tower upper part 110a and the temporary steel tower lower part 320 are removed, the temporary foundation 122 will be removed (step S192). At this time, in this embodiment, since the temporary foundation 122 is constructed in the existing site 102, it is not necessary to remove the whole. Accordingly, only the portion near the ground of the temporary foundation 122 is removed. As a result, the removal work can be simplified, and the time and cost required for the removal work can be shortened, and the construction period can be shortened and the construction cost can be reduced. And as shown in FIG.7 (g) and (h), the new steel tower 130 is completed and the said steel tower rebuilding construction is completed.

  As described above, also in the steel tower rebuilding method according to the third embodiment, the new foundation 132 of the new steel tower 130 is constructed at the same position as the old foundation 112 of the existing steel tower 110 by using the temporary steel tower lower part 320. Can do. Therefore, it is possible to efficiently perform the steel tower rebuilding work without purchasing additional land. Further, in this steel tower rebuilding method, by constructing the temporary foundation 122 at substantially the midpoint of each of the four sides of the quadrangle having the old foundation 112 as a vertex, interference between the existing steel tower lower part 110b and the temporary steel tower lower part 320 is alleviated. The work efficiency can be improved.

(Fourth embodiment)
In the steel tower rebuilding method according to the fourth embodiment, the number of temporary foundations 122 is the same as that of the first embodiment, but the temporary foundation 122 is constructed inside the old foundation 112 and the root of the existing steel tower 110 is formed by the lower part of the temporary steel tower. It differs from the first embodiment in that the opening is reduced (hereinafter referred to as an existing reduced root opening).

  8 and 9 are schematic diagrams for explaining the steel tower rebuilding method according to the fourth embodiment. In addition, since the procedure of the steel tower rebuilding method of 4th Embodiment is the same as that of the steel tower rebuilding method of 1st Embodiment, refer FIG. 3 for a flowchart. Moreover, about the element which has the function and structure substantially the same as the component of the steel tower rebuilding method of 1st Embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  When rebuilding the existing steel tower 110 by the steel tower rebuilding method according to the fourth embodiment, first, as shown in FIGS. 8 (a) and (b), on the diagonal line inside the square with the old foundation 112 of the existing steel tower 110 as the apex, That is, the temporary foundation 122 is constructed inside the old foundation 112 (step S172). Then, as shown in FIGS. 8C and 8D, the temporary steel tower lower portion 420 is constructed on the temporary foundation 122 (step S174). By installing the temporary foundation 122 inside the old foundation 112 in this way, the temporary steel tower lower part 420 is also built inside the existing steel tower lower part 110b, that is, in the existing site 102. Accordingly, interference between the existing steel tower lower part 110b or the newly installed steel tower lower part and the temporary steel tower lower part 420 is alleviated, so that it is possible to increase the work efficiency in removing or constructing them.

  Next, the existing steel tower 110 and the temporary steel tower lower part 420 are connected, and the existing steel tower upper part 110a is supported by the temporary steel tower lower part 420 (step S176). Thereafter, the existing steel tower lower part 110b is removed as shown in FIGS. 8E and 8F (step S178), and then the old foundation 112 is removed as shown in FIGS. 8G and 8H (step S180). ). Then, the new foundation 132 is constructed at the position where the old foundation 112 was provided as shown in FIG. 9A (step S182), and the existing steel tower upper part 110a and the temporary steel tower lower part 420 are shown in FIG. 9C. Is constructed on the new foundation 132 (step S184). Also in this embodiment, since the new foundation 132 is provided in the existing site 102 as shown in FIG. 9 (b), the new steel tower 130 is also constructed in the existing site 102 as shown in FIG. 9 (d).

  When the transmission line 104 stretched over the existing tower 110 is moved to the new tower 130 (step S186), as shown in FIGS. 9E and 9F, the existing tower upper portion 110a is removed (step S188). The temporary steel tower lower part 420 is removed (step S190), and the temporary foundation 122 is removed (step S192). Also in this embodiment, since the temporary foundation 122 is constructed in the existing site 102, only the portion near the ground of the temporary foundation 122 is removed. As a result, the removal work can be simplified, the construction period can be shortened, and the construction cost can be reduced. And as shown in FIG.9 (g) and (h), the new steel tower 130 is completed and the said steel tower rebuilding construction is completed.

  As described above, also in the steel tower rebuilding method according to the fourth embodiment, the new steel tower 130 can be constructed at the same position as the existing steel tower 110 by using the temporary steel tower lower portion 420 provided in the existing site 102. It is possible to improve the efficiency of the steel tower rebuilding work. Further, by constructing the lower part of the temporary tower 420 inside the existing tower 110, the interference between the lower part 110b of the existing tower or the lower part of the new tower and the lower part 420 of the temporary tower is alleviated, and the working efficiency in removing or constructing them is increased. It becomes possible.

(Fifth embodiment)
The steel tower rebuilding method according to the fifth embodiment is the same in the number of temporary foundations 122 as in the first embodiment, but is the first in that the new steel tower is supported by the lower part of the temporary steel tower with the root opening expanded. It is different from the embodiment (hereinafter referred to as a newly established root spread).

  FIGS. 10 and 11 are schematic diagrams for explaining the steel tower rebuilding method according to the fifth embodiment, and FIG. 12 is a flowchart for explaining the steel tower rebuilding method according to the fifth embodiment. Moreover, about the element which has the function and structure substantially the same as the component of the steel tower rebuilding method of 1st Embodiment, description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  When rebuilding the existing steel tower 110 by the steel tower rebuilding method according to the fifth embodiment, first, the temporary foundation 122 is constructed around the old foundation 112 of the existing steel tower 110 as shown in FIGS. 10 (a) and 10 (b). S572). Then, as shown in FIGS. 10C and 10D, the temporary steel tower lower part 520 is constructed on the temporary foundation 122 (step S574), and the new steel tower 110 is newly installed on the temporary steel tower lower part 520 so as to surround the upper part of the existing steel tower 110. An upper part of the steel tower 130 (hereinafter referred to as a new steel tower upper part 130a) is constructed (step S576).

  As described above, since the temporary foundation is provided around the old foundation 112, that is, outside the existing site 102, the temporary steel tower lower part 520 is also provided outside the existing site 102. However, also in this embodiment, since the temporary foundation 122 and the temporary steel tower lower part 520 are removed after construction of the new steel tower 130, the steel tower rebuilding work can be performed only by temporarily renting the land around the existing site 102. Moreover, by constructing only the temporary steel tower lower part 520, costs and time can be reduced as compared with the conventional construction of the entire temporary steel tower, and the efficiency of the steel tower rebuilding work can be improved.

  When the new steel tower upper part 130a is constructed, the transmission line 104 is moved from the existing steel tower 110 to the new steel tower upper part 130a (step S578). Thereafter, the existing tower 110 is removed as shown in FIGS. 10E and 10F (step S580), and the old foundation 112 is removed as shown in FIGS. 10G and 10H (step S582).

  Next, as shown in FIG. 11 (a), the new foundation 132 is constructed at the position where the old foundation 112 was provided (step S584), and as shown in FIGS. 11 (c) and (d), on the new foundation 132. In addition, a lower part of the new steel tower 130 (hereinafter referred to as a new steel tower lower part 130b) is constructed inside the temporary steel tower lower part 520 (step S586). Then, the new tower upper portion 130a and the new tower lower portion 130b are connected, and the new tower upper portion 130a is supported by the new tower lower portion 130b (step S588). At this time, since the new foundation 132 is provided in the existing site 102 as shown in FIG. 11 (b), the new steel tower lower part 130b is also constructed in the existing site 102 as shown in FIG. 11 (d). The steel tower 130 is completed.

  When the new tower 130 is completed, as shown in FIGS. 11E and 11F, the lower part of the temporary tower 520 is removed (step S590), and the temporary foundation 122 is removed from the land around the existing site 102 (step S592). . Thereby, as shown in FIGS. 11 (g) and 11 (h), there is no structure outside the existing site 102, and the steel tower rebuilding work is completed.

  As described above, according to the tower rebuilding method according to the fifth embodiment, the new foundation 132 is placed at the same position as the old foundation 112 by temporarily supporting the upper part 130a of the new tower using the lower part 120 of the temporary tower. It is possible to construct a new steel tower 130 at the same position as the existing steel tower 110. Therefore, even with this tower rebuilding method, even if it is not possible to purchase additional land around the existing site 102, the tower rebuilding work can be carried out efficiently only on leased land, and the construction period can be shortened and the construction cost reduced. Reduction can be achieved. Further, by constructing only the lower part of the temporary tower 520, costs and time can be reduced as compared with the conventional temporary work method, and the efficiency of the rebuilding work of the tower can be improved.

  In addition, in said 5th Embodiment, although the case where the temporary foundation 122 was constructed around the old foundation 112 of the existing steel tower 110 was illustrated, it is not limited to this, and a temporary foundation is constructed in the inside of the old foundation 112. May be. Therefore, the existing twist and inter-leg pile described in the third embodiment can be applied to the case where the new steel tower upper part 130a is supported by the temporary steel tower lower part 520 as in the fifth embodiment.

  As described above, according to the steel tower rebuilding method according to the present embodiment, the area around the existing steel tower to be rebuilt is urbanized, a temporary steel tower is constructed, and the transmission line is moved (the enclosing method is applied). Even if this is not possible, it is necessary to rent the land around the existing steel tower temporarily, and reconstruct the steel tower over which a special high-voltage overhead electric wire of 170 kV or more will be stretched without violating the electrical equipment technical standards. Can be done. In addition, in the steel tower rebuilding method according to the present embodiment, in the wire transfer from the existing steel tower to the new steel tower, the moving direction of the transmission line is the vertical direction (moving from the bottom to the top). The load applied to the front and rear steel towers does not increase. Therefore, it is not necessary to reinforce the front and rear steel towers and the foundations thereof, and it is possible to shorten the construction period and reduce costs.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  The present invention can be used as a steel tower rebuilding method for a steel tower rebuilding work.

DESCRIPTION OF SYMBOLS 102 ... Existing site, 104 ... Transmission line, 110 ... Existing steel tower, 110a ... Existing steel tower upper part, 110b ... Existing steel tower lower part, 112 ... Old foundation, 120 ... Temporary steel tower lower part, 122 ... Temporary foundation, 130 ... New steel tower, 130a ... New steel tower upper part, 130b ... New steel tower lower part, 132 ... New foundation, 220/320/420/520 ... Temporary steel tower lower part

Claims (6)

A tower rebuilding method used for a tower rebuilding work for removing an existing tower over which a transmission line is stretched and installing a new tower at a position where the existing tower was installed,
A temporary foundation is constructed around or inside the old foundation, which is the foundation of the existing steel tower,
Construction of the lower part of the temporary tower on the temporary foundation,
The upper part of the existing steel tower is supported by the lower part of the temporary steel tower,
Removing the lower part of the existing steel tower and the old foundation of the existing steel tower;
Install the new foundation at the position where the old foundation of the existing steel tower was established,
The new tower is constructed so as to surround the upper part of the existing tower on the new foundation,
Relocating the transmission line from the existing tower to the new tower,
A steel tower rebuilding method, wherein an upper part of the existing steel tower and a lower part of the temporary steel tower are removed. A tower rebuilding method used for a tower rebuilding work for removing an existing tower over which a transmission line is stretched and installing a new tower at a position where the existing tower was installed,
A temporary foundation is constructed around or inside the old foundation, which is the foundation of the existing steel tower,
Construction of the lower part of the temporary tower on the temporary foundation,
The upper part of the new steel tower is constructed so as to surround the upper part of the existing steel tower on the lower part of the temporary steel tower,
Relocating the transmission line from the existing tower to the new tower,
Removing the existing tower and the old foundation of the existing tower;
Install the new foundation at the position where the old foundation of the existing steel tower was established,
The lower part of the new steel tower is constructed inside the lower part of the temporary steel tower on the new foundation,
Support the upper part of the new steel tower by the lower part of the new steel tower,
The steel tower rebuilding method, wherein the lower part of the temporary steel tower is removed.   The temporary foundation is constructed by hitting two or more piles along two opposing sides of four sides of a quadrangle having the old foundation of the existing tower as a vertex. Item 3. The tower rebuilding method according to item 1 or 2.   3. The tower building according to claim 1, wherein the temporary foundation is constructed by hitting two or more piles along all four sides of a quadrilateral having the old foundation of the existing tower as an apex. Replacement method.   3. The tower rebuilding method according to claim 1, wherein the temporary foundation is constructed at substantially the midpoint of each of the four sides of a quadrangle having the old foundation of the existing tower as a vertex. 4.   The steel tower rebuilding method according to claim 1, wherein the temporary foundation is constructed on a diagonal line inside a quadrangle having the old foundation of the existing steel tower as a vertex.

Images