Electric pole fixing jig and method for reinforcing earthquake resistance of electric pole

Abstract

To provide a construction method for earthquake resistant reinforcing work of an electric pole capable of safely and quickly cutting a plastic hinge part including a PC steel wire.SOLUTION: A wire saw device 5 for cutting an object by rotationally driving a wire saw is rotationally driven by the wire saw device 5 in a state of being fixed to the PC electric pole EP by using an electric pole fixing tool 1, and a plastic hinge part including a PC steel wire C1 part of the PC electric pole EP is cut.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a method for performing earthquake-resistant reinforcement work on PC electrification poles and a pole fixing jig for fixing a wire saw device to a PC electrification pole. [Background technology]

[0002] In the Great East Japan Earthquake that occurred in 2011, railway structures also suffered significant damage, and in particular, unexpected horizontal loads were applied to PC electrification poles erected on railway viaducts, causing the concrete to collapse, leading to the PC electrification poles exhibiting brittle fractures and the risk of contact with running trains, creating safety issues. There was also the problem that the collapse of PC electrification poles was a factor in the length of time it took for railway operations to resume.

[0003] Therefore, a seismic reinforcement method was proposed in which a steel pipe unit with rebar welded to the outside of the PC electrification pole was installed, the gap between the steel pipe unit and the PC electrification pole was filled with non-shrinkage mortar, and the PC steel wires of the PC electrification pole were cut at the middle of the steel pipe unit to give the PC electrification pole deformation capacity.In this way, by carrying out seismic reinforcement work on the PC electrification pole, it became possible for the PC electrification pole to absorb earthquake energy through deformation of the rebar.

[0004] For example, Patent Document 1 discloses a column fixing structure 1 for fixing a column 5, the lower part of which is embedded in a foundation 4 and in which column reinforcing wires 7 are arranged vertically inside the column 5, to the foundation 4, the column fixing structure 1 comprising a lower reinforcing section 20 provided at the lower part of an outer periphery 5X of the column 5, an upper reinforcing section 40 provided on the outer periphery 5X above the lower reinforcing section 20, an intermediate reinforcing section 30 provided on the outer periphery 5X of the column 5 between the lower reinforcing section 20 and the upper reinforcing section 40, and a plurality of repair reinforcing wires L, the lower ends of which are located above the foundation 4 and connected to the lower reinforcing section 20 and the upper ends of which are connected to the upper reinforcing section 40, and the column reinforcing wires 7 are separated at a vertical position P of the intermediate reinforcing section 30 (see paragraphs

[0020] to

[0047] of the specification of Patent Document 1 and Figures 1 to 8 of the drawings, etc.).

[0005] However, in the seismic reinforcement work for PC electrification poles that construct the column fixing structure 1 described in Patent Document 1, it was necessary to install half-split steel pipe units, each with its entire circumference split in half, on the outside of the PC electrification pole. In this case, because the gap between the PC electrification pole and the wall parapet is narrow, about 65 mm, there was a problem in that it was difficult to move the steel pipe unit, which weighs about 100 kg even when split in half, by prying it with a crowbar or the like and installing it in the specified position.

[0006] In particular, there was a risk of hands getting caught when installing steel pipe units in narrow gaps, and the work took longer than expected during the limited hours at night when trains were not running, meaning that the earthquake-resistant reinforcement work could not be completed within the allotted time.

[0007] Furthermore, after combining the halves of the steel pipe units into a circular shape, when pouring the non-shrink mortar, a gap forms between the lower steel pipe unit and the ground, requiring work to fill the gap beforehand. However, as mentioned above, the gap is narrow, making it difficult to work properly, resulting in the problem of the filled non-shrink mortar leaking. While it was possible to fill the gap between the lower steel pipe unit and the ground with urethane foam, it took time for the urethane foam to harden, which resulted in the problem of it taking a long time to complete the filling of the non-shrink mortar.

[0008] Therefore, the applicant of the present application proposed a construction jig and construction method for earthquake-resistant reinforcement work on utility poles, as described in Patent Document 2. Patent Document 2 discloses a construction method for earthquake-resistant reinforcement work on utility poles, in which a construction jig for earthquake-resistant reinforcement work is used to rotate and install a reinforcing steel pipe unit in a narrow gap without having to lift it manually by running the reinforcing steel pipe unit on a ring rail using guide rollers while hanging it from a hanger member (see claim 6 in the scope of claims of Patent Document 2, paragraphs

[0059] to

[0082] of the specification, Figures 1 to 7 of the drawings, etc.).

[0009] In the construction method for earthquake-resistant reinforcement of utility poles described in Patent Document 2, a wire saw is inserted into the fully-contained vinyl spiral pipe of the middle steel pipe unit of an earthquake-resistant reinforcement steel pipe unit, and the non-shrinkage mortar and PC steel wire are cut at a predetermined cutting position to form a plastic hinge. However, the surface of the reinforcement steel pipe unit is curved with a small radius of curvature, making it difficult to secure the wire saw device. Therefore, currently, the wire saw driver is secured with a nylon sling or similar to secure the wire saw during cutting. However, this can sometimes shift due to weight or vibration during the cutting operation, which can lead to serious accidents such as wire saw cutting.

[0010] To solve this problem, it is possible to drill holes in the concrete slab of the platform near the utility pole and fix the drive unit, but this would require drilling holes in the finished surface of the slab outside the construction area, and would also create problems such as the wire saw route becoming complicated and the difficulty of fixing the driven pulley, etc. Furthermore, if the floor near the utility pole is made of steel plate or a gutter cover and not a concrete slab, fixing the unit would not be possible. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-83745 [Patent Document 2] Patent No. 7303363 Summary of the Invention [Problem to be solved by the invention]

[0012] Therefore, the present invention was devised in consideration of the above-mentioned problems, and its purpose is to provide a construction method for earthquake-resistant reinforcement work on utility poles that can safely and quickly cut plastic hinge parts, including PC steel wires. [Means for solving the problem]

[0013] The construction method for earthquake-resistant reinforcement work on utility poles according to claim 1 is a construction method for earthquake-resistant reinforcement work on utility poles in which a reinforcing steel pipe unit is installed on the outside of an existing PC electrification pole to reinforce it, and is characterized in that a wire saw device that rotates and cuts an object is fixed to the PC electrification pole using a pole fixing jig, and the wire saw is rotated by the wire saw device to cut the plastic hinge portion, including the PC steel wire of the PC electrification pole.

[0014] The utility pole fixing jig of claim 2 is a utility pole fixing jig that fixes a wire saw device that cuts the plastic hinge portion, including the PC steel wire, of an existing PC electrification pole to the PC electrification pole in earthquake-resistant reinforcement work in which a reinforcing steel pipe unit is installed on the outside of the PC electrification pole to reinforce the pole, and is characterized in that it comprises a jig plate that is arc-shaped in plan view and spaced a predetermined distance from the outer peripheral surface of the PC electrification pole, and a nut that fixes the wire saw, and bolt insertion holes are drilled at the end of the jig plate to bolt to the reinforcing steel pipe unit, and the bolt insertion holes are elongated holes for length adjustment. [Effects of the Invention]

[0015] According to the inventions of claims 1 and 2, the wire saw device is fixed to the PC pole using a utility pole fixing jig, so the wire saw device can be fixed quickly and reliably in a short time. Furthermore, the wire saw is rotated and driven while the wire saw device is fixed to the steel pipe unit to cut the plastic hinge portion including the PC steel wire, so the plastic hinge portion can be cut safely and quickly. Furthermore, because the wire saw device is fixed to the steel pipe unit, the positions of the bolts and reinforcing bars in the steel pipe unit remain unchanged, so the reinforcing bars can be cut without being damaged by the wire of the wire saw. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view that schematically shows an overview of the seismic reinforcement work for an existing PC electrification pole and a seismic reinforcement structure reinforced with seismic steel pipe units. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, showing the upper and lower earthquake-resistant reinforcement structures. [Figure 3] FIG. 3 is a cross-sectional view taken along line BB in FIG. 1, showing the earthquake-resistant reinforcement structure in the middle section. [Figure 4] FIG. 4 shows the rear part of the upper steel pipe unit (lower steel pipe unit), where (a) is a plan view and (b) is a side view. [Figure 5] FIG. 5 shows a front part of the upper steel pipe unit (lower steel pipe unit), where (a) is a plan view and (b) is a side view. [Figure 6] FIG. 6 shows a utility pole fixing jig according to an embodiment of the present invention, where (a) is a front development view and FIG. 6(b) is a plan view. [Figure 7] FIG. 7 is a diagram showing the same utility pole fixing jig, where (a) is a front view and (b) is a right side view. [Figure 8] FIG. 8 is a horizontal cross-sectional view showing the state in which the utility pole fixing jig is attached along the outer periphery of the earthquake-resistant reinforcement steel pipe unit, taken horizontally near the interrupted steel pipe unit. [Figure 9] FIG. 9 is a front view showing the state in which the utility pole fixing jig is attached along the outer periphery of the earthquake-resistant reinforcement steel pipe unit. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of a method for performing seismic reinforcement work on a utility pole and a utility pole fixing jig according to the present invention will be described in detail with reference to the drawings.

[0018] First, using Figures 1 to 5, we will explain the seismic reinforcement steel pipe unit 10 that seismically reinforces an existing PC electrification pole EP in seismic reinforcement work for a utility pole. Figure 1 is a perspective view that schematically shows an overview of the seismic reinforcement work for an existing PC electrification pole EP and a seismic reinforcement structure 100 reinforced with the seismic reinforcement steel pipe unit 10. Also, Figure 2 is a cross-sectional view taken along line AA in Figure 1, showing the upper and lower seismic reinforcement structures 100, and Figure 3 is a cross-sectional view taken along line BB in Figure 1, showing the middle seismic reinforcement structure 100.

[0019] As shown in Figure 1, the seismic reinforcement work for utility poles according to the present invention involves installing seismic reinforcement steel pipe units 10 around the periphery of existing PC utility poles EP, which have been erected on a railway viaduct as a foundation F1, and filling the gaps S1 between them with non-shrinkage mortar M1 to integrate and reinforce the poles, thereby constructing a seismic reinforcement structure 100. The dashed-dotted line in Figure 1 indicates the position of the wall parapet WB.

[0020] The PC electrification pole EP is assumed to be a PC electrification pole with a diameter of 400 mm, and as described in the Background Art section, although it is reinforced with internal PC steel wires PC1, there is a risk that the concrete will collapse due to the input of unexpected horizontal loads such as those caused by a major earthquake, causing the PC electrification pole EP to undergo brittle failure. For this reason, in the electric pole earthquake reinforcement work according to the present invention, as will be described in detail later, the PC electrification pole EP is reinforced with earthquake-resistant reinforcement steel pipe units 10 with reinforcing bars welded to the outer periphery, and then the PC steel wires PC1 are cut with a wire saw device 5. As a result, the earthquake-resistant reinforcement structure 100 is configured so that the reinforcing bars of the earthquake-resistant reinforcement steel pipe units 10 undergo plastic deformation, absorbing input energy during a major earthquake and preventing brittle failure.

[0021] This earthquake-resistant reinforcement steel pipe unit 10 is made of steel such as general structural rolled steel plate (SS400) that has been treated with anti-rust treatment such as hot-dip galvanizing, and as shown in Figure 1, it comprises an upper steel pipe unit 11, a middle steel pipe unit 12, and a lower steel pipe unit 13. In addition, a plurality of reinforcing bars 14 are welded to the outer periphery of these upper steel pipe unit 11 and lower steel pipe unit 13, and protective steel material 15 is also attached to prevent deformation at the welded joints or their boundaries of the reinforcing bars, which are weak points in terms of strength, when the reinforcing bars 14 deform into a dogleg when absorbing earthquake energy.

[0022] In addition, in the earthquake-resistant reinforcement work for utility poles according to the present invention, a mortar injection hole IN and a mortar discharge confirmation hole OUT are drilled which communicate with the internal cavity EPa of the PC utility pole EP, and the internal cavity EPa is also reinforced by injecting and filling it with non-shrinkage mortar M2.

[0023] The upper steel pipe unit 11 and the lower steel pipe unit 13 are a pair of vertically symmetrical components connected by multiple (eight in the illustrated embodiment) reinforcing bars 14. Therefore, in the following, the lower steel pipe unit 13 will be described as being substituted for the upper steel pipe unit 11 by only using the reference numeral, and a detailed description will be omitted.

[0024] (Upper steel pipe unit, lower steel pipe unit) As shown in Figures 4 and 5, the upper steel pipe unit 11 (lower steel pipe unit 13) is divided into two parts: a rear part 11a (13a) on the wall parapet WB side and a front part 11b (13b) on the track side, so that it can be installed in the narrow gap between the wall parapet WB. Figure 4 shows the rear part 11a (13a) of the upper steel pipe unit 11 (lower steel pipe unit 13), where (a) is a plan view and (b) is a side view. Figure 5 shows the front part 11b (13b) of the upper steel pipe unit 11 (lower steel pipe unit 13), where (a) is a plan view and (b) is a side view.

[0025] As shown in Figure 4(a), the rear part 11a (13a) of the upper steel pipe unit 11 (lower steel pipe unit 13) is a member based on a cylindrical body 110 (130) that has been bent from a steel material such as a 9 mm thick general structural rolled steel plate (SS400) into a half-cylinder shape with an inner surface curvature radius of 245 mm.

[0026] 4(a) and 4(b), five lifting holes h1 are drilled along the edge of the upper end of the cylindrical body 110 (130) to insert shackles for lifting with the construction jig of Patent Document 1. The lifting holes h1 in this embodiment have a diameter of 10 mm.

[0027] Furthermore, as shown in Figures 4(a) and 4(b), the cylindrical body 110 (130) has a plurality of bolt holes 112 (eight in the illustrated embodiment) for bolting to the cylindrical body 111 (131) of the front part 11b (13b). Nuts 113 for threading onto M20 bolts are welded to the inner peripheral surface of the cylindrical body 110, which is inside the bolt holes 112. Therefore, the upper steel pipe unit 11 (lower steel pipe unit 13) can be easily joined to the front part 11b (13b) and the rear part 11a (13a) in a short time by simply screwing an M20 bolt into the bolt hole 115 from the outside of the cylindrical body 111 of the front part 11b (13b) described below.

[0028] 4(a) and 4(b), a 10 mm high spacer 114 (134) is provided above the center line of the inner circumferential surface of the cylindrical body 110 (below the center line of the inner circumferential surface of the cylindrical body 130) to protrude therefrom. This spacer 114 (134) is made of a 16 mm thick flat steel bar.

[0029] 4(a) and 4(b), reinforcing bars 14 made of D25 (SD390) deformed steel bars are welded to the outer periphery of the cylindrical body 110. The reinforcing bars 14 are 900 mm long, and both longitudinal ends are welded within 200 mm of their top and bottom ends. However, the middle section of the reinforcing bars 14 is not fixed but is left free, and this free section undergoes plastic deformation during an earthquake to absorb the input energy.

[0030] 4(a), the reinforcing bar 14 is firmly fixed by K-flare welding to the flat bar 14a within a range of 200 mm from the end, with the flat bar 14a being 4.5 mm thick and 200 mm long, used as a spacer, slightly lifted from the outer surface of the cylindrical body 110. The welded portion is integrated with the cylindrical body 110, which is a reinforcing steel plate, and by being spaced from the cylindrical body 110 by the thickness of the flat bar 14a, the free, unwelded portion is prevented from coming into contact with the cylindrical body 110 during plastic deformation of the reinforcing bar 14, which would impair its energy absorption performance.

[0031] On the other hand, as shown in Figure 5(a), the front part 11b (13b) of the upper steel pipe unit 11 (lower steel pipe unit 13) is a member having as its base a cylindrical body 111 (131) which is bent from a steel material such as a 9 mm thick general structural rolled steel plate (SS400) into a half-cylindrical shape with an inner surface curvature radius of 254 mm.

[0032] Also, as shown in Figures 5(a) and 5(b), three lifting holes h1, each 10 mm in diameter, are drilled along the edge of the upper end of this cylindrical body 111 (130), similar to the cylindrical body 110.

[0033] (Middle steel pipe unit) As shown in Figure 3, the middle steel pipe unit 12 is a separate component from the upper steel pipe unit 11 and the lower steel pipe unit 13 so that it can be opened when cutting the PC steel wire PC1 with the wire saw device 5 as described below, and is a component based on a cylindrical body 120 (121) that has been bent from a steel material such as a 4.5 mm thick general structural rolled steel plate (SS400) into a half-cylindrical shape with an inner surface curvature radius of 245 mm.

[0034] Furthermore, as shown in Fig. 3, the cylindrical body 120 of the rear part 12a is provided with a plurality of bolt holes for bolting to the cylindrical body 121 of the front part 12b, so that the front part 12b and the rear part 12a can be bolted together. Fig. 3 is a cross-sectional view taken along line BB in Fig. 1, showing the middle-stage earthquake-resistant reinforcement structure 100. Reference numeral 14 denotes the reinforcing bar 14 described above.

[0035] [Utility pole fixing jig] Next, a utility pole fixing jig 1 according to an embodiment of the present invention will be described with reference to Figures 6 and 7. Figure 6 shows the utility pole fixing jig 1 according to an embodiment of the present invention, with (a) being a front development view and Figure 6(b) being a plan view. Also, Figure 7 shows the utility pole fixing jig 1, with (a) being a front view and (b) being a right side view.

[0036] As shown in Figures 6 and 7, the utility pole fixing jig 1 of this embodiment includes a jig plate 2 that is arc-shaped in plan view and spaced a predetermined distance from the outer peripheral surface of the steel pipe unit 10, and a nut 3 that fixes the wire saw device 5 described below, and has the function of fixing the wire saw device 5 to the steel pipe unit 10 during utility pole earthquake reinforcement work (see also Figures 8 and 9).

[0037] The jig plate 2 is made of a 6 mm thick steel plate such as general structural rolled steel plate (SS400), and as shown in Figure 6(a), it consists of a 75 mm wide upper band plate portion 21 in the shape of a band, a similarly 75 mm wide lower band plate portion 22 in the shape of a band, and a 260 mm wide central plate portion 23 that connects these upper band plate portion 21 and lower band plate portion 22 vertically, and the shape before bending is an H-shaped steel plate as a whole when viewed in a front unfolded view.

[0038] As shown in Figure 6(b), this jig plate 2 is made from a steel plate that is H-shaped in a front unfolded view and is bent into a semi-cylindrical shape in a plan view with an inner diameter R1 = 294 mm so that it can be attached along the outer periphery of the earthquake-resistant reinforcement steel pipe unit 10 from the outside of the earthquake-resistant reinforcement steel pipe unit 10 attached to the PC electrification pole EP (see also Figure 8).

[0039] Furthermore, bolt insertion holes 21a, 21a are drilled at the left and right (horizontal) ends of the upper band plate portion 21, through which M20 bolts are inserted to connect the front part 11b (12b) and rear part 11a (12a) of the upper steel pipe unit 11 or middle steel pipe unit 12 of the earthquake-resistant reinforcement steel pipe unit 10, and bolt insertion holes 22a, 22a are drilled at the left and right (horizontal) ends of the lower band plate portion 22, through which M20 bolts are inserted to connect the front part 13b and rear part 13a of the lower steel pipe unit 13. These bolt insertion holes 21a, 21a and bolt insertion holes 22a, 22a are elongated holes so that their lengths can be adjusted depending on the installation state of the earthquake-resistant reinforcement steel pipe unit 10.

[0040] A through hole 23a is drilled slightly above the center of the central plate portion 23, 161 mm from the upper end of the upper band plate portion 21 and 214 mm from the lower end of the lower band plate portion 22, and an M14 nut 3 for fixing the wire saw device 5 is welded to the outer peripheral surface of the front side facing the track.

[0041] Next, the use state of the utility pole fixing jig 1 will be described with reference to Figures 8 and 9. Figure 8 is a horizontal cross-sectional view taken horizontally near the middle steel pipe unit 12 to show the state in which the utility pole fixing jig 1 is attached along the outer periphery of the earthquake-resistant reinforcement steel pipe unit 10, and Figure 9 is a front view showing the state in which the utility pole fixing jig 1 is attached along the outer periphery of the earthquake-resistant reinforcement steel pipe unit 10.

[0042] As shown in Figure 8, the utility pole fixing jig 1 is attached from the outside of the earthquake-resistant reinforcement steel pipe unit 10 along the outer periphery of the earthquake-resistant reinforcement steel pipe unit 10 so that the inner circumferential surface of the jig plate 2 abuts against the reinforcing bars 14. Then, M20 bolts that connect the front and rear parts of the earthquake-resistant reinforcement steel pipe unit 10 are inserted into the bolt insertion holes 21a, 22a of the upper band plate portion 21 and the lower band plate portion 22, and the utility pole fixing jig 1 is fixed to the earthquake-resistant reinforcement steel pipe unit 10 by bolting.

[0043] As shown in Figure 9, the bolt insertion holes 21a of the upper band plate portion 21 are fixed to the middle steel pipe unit 12, and the bolt insertion holes 22a of the lower band plate portion 22 are fixed to the lower steel pipe unit 13. However, as shown by the dashed double-dashed lines in Figure 1, there are two locations, one above and one below, that are cut by the wire saw device 5, so the wire saw device 5 is bolted to the earthquake-resistant reinforcement steel pipe unit 10 via the utility pole fixing jig 1 using nuts 3 while adjusting the position appropriately. Of course, since the fixing position of the wire saw device 5 to be used will differ, it is not limited to the illustrated form, and the bolt insertion holes 21a of the upper band plate portion 21 may also be fixed to the upper steel pipe unit 11.

[0044] [Construction method for earthquake-resistant reinforcement of utility poles] Next, a construction method for earthquake-resistant reinforcement of utility poles according to an embodiment of the present invention will be described with reference to Figures 1 to 5. The description will be given taking as an example a case where an existing PC electricity pole EP is reinforced with the above-mentioned earthquake-resistant reinforcement steel pipe unit 10. However, it is assumed that construction will be carried out using the construction jig described in Patent Document 2 (not shown), but since the present invention is an invention related to a utility pole fixing jig, description of the construction jig will be omitted.

[0045] <Advance preparation> As a preparatory step for carrying out the method for seismic reinforcement of utility poles according to this embodiment, the type of foundation F1 on which the existing PC utility pole EP, which is the target of the seismic reinforcement work, is erected, the presence or absence of obstacles, in particular the presence or absence of a wall parapet and the distance between the wall parapet WB and the PC utility pole EP, are checked in advance. Of course, if there are any splices or other objects that will hinder the work, they should be removed before construction begins.

[0046] (Electrification pole drilling process) Next, the electrification pole drilling process is carried out to drill holes for injecting non-shrinkage mortar M2 into the internal cavity EPa in the electrification pole interior filling mortar pouring process described below (see Figures 1 and 2). Specifically, a drilling machine is fixed to the PC electrification pole EP, and mortar injection holes IN and mortar discharge confirmation holes OUT are drilled from the outer surface of the PC electrification pole EP, which communicate with the internal cavity EPa (see Figure 1).

[0047] <Process for pouring mortar to fill the interior of an electricity pole> As shown in Figures 1 to 3, in the construction method for seismic reinforcement work of utility poles according to this embodiment, a mortar pouring process for filling the interior cavity EPa with non-shrinkage mortar M2 is carried out using the mortar injection holes IN and mortar discharge confirmation holes OUT drilled (drilled) in the PC utility pole EP in the previous process.

[0048] Specifically, non-shrinkage mortar is filled from the top end of the earthquake-resistant reinforcement steel pipe unit 10 up to 1D (diameter of the PC electrification pole EP) above.

[0049] <Seismic reinforcement steel pipe unit installation process> Next, in the construction method for earthquake-resistant reinforcement work on utility poles according to this embodiment, an earthquake-resistant reinforcement steel pipe unit installation process is carried out in which the aforementioned earthquake-resistant reinforcement steel pipe unit 10 is installed in a predetermined position relative to the PC electrification pole EP to be reinforced.

[0050] <Steel pipe unit mortar filling process> Next, as shown in Figures 1 to 3, in the construction method for utility pole earthquake reinforcement work according to this embodiment, a steel pipe unit mortar filling process is carried out in which non-shrinkage mortar M1 is filled into the gap S1 between the earthquake reinforcement steel pipe unit 10 installed on the outer periphery of the existing PC electricity pole EP and the PC electricity pole EP.

[0051] <Plastic hinge cutting process> Next, the compressive strength of the non-shrinkage mortar M1 poured in the steel pipe unit mortar filling process was 24 N / mm 2 After that, in the construction method for earthquake-resistant reinforcement of utility poles according to this embodiment, a wire saw of the wire saw device 5 is inserted into the fully-contained vinyl spiral pipe 12c of the middle steel pipe unit 12 of the earthquake-resistant reinforcement steel pipe unit 10, and the non-shrinkage mortar M1, M2 and the PC steel wire PC1 are cut at the cutting position indicated by the two-dot chain line in Figure 1, thereby performing a plastic hinge cutting step to form a plastic hinge portion.

[0052] At this time, in the construction method for earthquake-resistant reinforcement of utility poles according to this embodiment, as described above, the utility pole fixing jig 1 is attached from the outside of the earthquake-resistant reinforcement steel pipe unit 10 so that the inner peripheral surface of the jig plate 2 abuts against the reinforcing bars 14. Then, M20 bolts that connect the front part and rear part of the earthquake-resistant reinforcement steel pipe unit 10 are inserted into the bolt insertion holes 21a, 22a of the upper band plate portion 21 and the lower band plate portion 22, and the utility pole fixing jig 1 is fixed to the earthquake-resistant reinforcement steel pipe unit 10 by bolting.

[0053] In this way, in this process, the wire saw device 5 is bolted to the earthquake-resistant reinforcement steel pipe unit 10 firmly attached to the PC electricity pole EP via the utility pole fixing jig 1, eliminating the need to fasten and secure the wire saw device 5 with a nylon sling or the like. This eliminates the risk of the wire saw device becoming misaligned due to weight or vibration during the cutting work, as occurs in conventional methods of earthquake-resistant reinforcement work on utility poles, and reliably prevents serious accidents such as wire saw cutting accidents and damage to rebar caused by the wire saw.

[0054] In addition, with the wire saw device 5 fixed to the PC electrification pole EP, the wire saw is rotated and driven by the wire saw device 5 to cut the plastic hinge portion shown by the dotted line in Figure 1, including the PC steel wire PC1, so that the plastic hinge portion can be cut safely and quickly.

[0055] <Process for filling cut areas with non-shrinkage mortar> Next, a non-shrinkage mortar filling process is carried out to fill the gaps in the plastic hinge sections cut in the plastic hinge section cutting process with non-shrinkage mortar. Specifically, an injection pipe, an air vent pipe, etc. are installed, and non-shrinkage cement milk is injected and filled. Once this process is completed and the mortar has hardened and attained a predetermined strength, the seismic reinforcement work for a utility pole according to the present embodiment is completed, in which the existing PC utility pole EP is reinforced with the above-mentioned seismic reinforcement steel pipe unit 10.

[0056] According to the execution method for utility pole earthquake-resistant reinforcement work and the utility pole fixing jig 1 for the wire saw device 5 according to the present embodiment described above, the wire saw device 5 is fixed to the PC electrification pole EP using the utility pole fixing jig 1, so that the wire saw device 5 can be fixed quickly and reliably in a short time. Furthermore, the wire saw is rotationally driven to cut the plastic hinge portion including the PC steel wire PC1 with the wire saw device 5 fixed to the PC electrification pole EP via the utility pole fixing jig 1, so not only can the plastic hinge portion be cut safely and quickly, but accidents in which the reinforcing bars are damaged by the wires of the wire saw can also be reliably prevented.

[0057] The above has described in detail the method for performing seismic reinforcement work on utility poles and the utility pole fixing jig 1 of the wire saw device 5 according to an embodiment of the present invention, but the above-mentioned and illustrated embodiments are merely specific embodiments for carrying out the present invention. Therefore, the technical scope of the present invention should not be interpreted as being limited by these embodiments. [Explanation of symbols]

[0058] 100: Earthquake-resistant reinforced structure 10: Earthquake-resistant reinforcement steel pipe unit 11: Upper steel pipe unit h1: Lifting hole 11a, 13a: Back parts 11b, 13b: Front parts 110, 111, 130, 131: Cylindrical body 112,132:Bolt holes 113: Nut 114,134:Spacer 115,135:Bolt holes 12: Middle steel pipe unit 12a: Back part 12b: Front part 13c: Fully compressed vinyl spiral tube 13: Lower steel pipe unit 14: Reinforced concrete 14a: Flat bar 15: Protective steel material 1: Utility pole fixing jig 2: Jig plate 21: Upper band plate part 21a: Bolt insertion hole 22: Lower band plate part 22a: Bolt insertion hole 23: Center plate 23a: Through hole 3: Nut 5: Wire saw device EP: PC electrification pole EPa: internal cavity PC1: PC steel wire S1: Gap WB: Wall parapet F1:Fundamentals IN: Mortar injection hole OUT: Mortar discharge confirmation hole M1, M2: Non-shrinkage mortar

Claims

1. A construction method for seismic reinforcement of electric poles in which a reinforcing steel pipe unit is installed on the outside of an existing PC electrification pole to reinforce it, A wire saw device that rotates and drives a wire saw to cut an object is fixed to the PC electrification pole using a pole fixing jig, and the wire saw is rotated by the wire saw device to cut the plastic hinge portion including the PC steel wire of the PC electrification pole. A construction method for earthquake-resistant reinforcement of utility poles characterized by the above.

2. In a seismic reinforcement work for a utility pole in which a reinforcing steel pipe unit is installed on the outside of an existing PC utility pole to reinforce the pole, a wire saw device that cuts a plastic hinge portion including the PC steel wire of the PC utility pole is fixed to the PC utility pole. A jig plate having an arc shape in a plan view and spaced a predetermined distance from the outer peripheral surface of the PC electrification pole, and a nut for fixing the wire saw device, Bolt insertion holes for bolting to the reinforcing steel pipe unit are drilled at the end of the jig plate, The bolt insertion hole is an elongated hole for length adjustment. A utility pole fixing jig characterized by the above.

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