Method for constructing a structure, spacer, and spacer mechanism

Abstract

To provide a construction method of a structure or the like that can suitably fix a reinforcement cage with spacers.SOLUTION: A caisson type pile is constructed by a step of rotating spacers 1 and abutting them to a reinforcement cage 3 from the state that the spacers 1 rotatably mounted to liner plates 2 are arranged along the liner plates 2 and the reinforcement cage 3 is installed inside the liner plates 2, and a step of placing concrete C inside the liner plates 2. The spacers 1 are rotatably mounted to the liner plates 2 in a vertical plane.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for constructing a structure and a spacer or the like used therefor. [Background technology]

[0002] The caisson foundation of a transmission tower is constructed by assembling rebar in a borehole and pouring concrete into the borehole. In recent years, in order to shorten the construction period, a rebar cage pre-assembled in a factory or the like is sometimes lowered into the borehole by a crane or the like, and then erected. Alternatively, an extendable rebar cage as described in Patent Document 1 can also be used.

[0003] A liner plate that forms the outer periphery of the caisson foundation is provided on the wall of the borehole, and a spacer is placed between the liner plate and the reinforcing bar cage to maintain a constant distance between them and to fix the reinforcing bar cage in the center of the borehole. The spacer can be attached to the reinforcing bar cage, but Patent Documents 2 and 3 also describe attaching the spacer to the liner plate in advance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-186538 [Patent Document 2] Japanese Patent Publication No. 2020-204163 [Patent Document 3] Japanese Patent Application Publication No. 08-27784 Summary of the Invention [Problem to be solved by the invention]

[0005] Reinforced concrete cages are pre-assembled in factories and transported to the site by land transport such as trucks and trailers, but the width of items that can be transported by truck or trailer is restricted by the Road Traffic Act, etc., and when transporting reinforced concrete cages for deep foundations, these restrictions sometimes mean that the cages must be transported without spacers attached.

[0006] In this case, the spacers are attached to the rebar cage just before it is erected, or they are attached at the mouth of the borehole while being lowered into the borehole by a crane, or workers descend into the borehole after the rebar cage has been erected inside the borehole to attach them.However, due to the large number of spacers required, the work takes time and there is a risk of delays in the construction period.

[0007] In this regard, it may be possible to avoid the above problem by attaching a spacer to the liner plate side as in Patent Documents 2 and 3, but both Patent Documents 2 and 3 involve assembling reinforcing bars inside a borehole to form a reinforcing bar cage, and when erecting a prefabricated reinforcing bar cage, there are problems such as interference between the spacer and the reinforcing bar cage.

[0008] The present invention has been made in consideration of the above problems, and aims to provide a method for constructing a structure in which a reinforcing bar cage can be suitably fixed using a spacer. [Means for solving the problem]

[0009] The first invention for solving the above-mentioned problems is a method for constructing a structure that is a vertical member, and an outer periphery having an inner cavity.a step of placing a spacer rotatably attached to the inside of the outer periphery along the outer periphery, with a reinforcing bar cage installed inside the outer periphery, and rotating the spacer to abut against the reinforcing bar cage; and a step of pouring concrete inside the outer periphery after abutting the spacer against the reinforcing bar cage, wherein the spacer has an arch-shaped shape that is convex toward the inside of the outer periphery in a vertical plane, and an upper tip is rotatably attached to the outer periphery within the vertical plane, and the spacer abuts against the reinforcing bar cage by rotating the spacer in the vertical plane around the upper tip. The second invention is a method for constructing a structure that is a vertical member, comprising: and an outer periphery having an inner cavity. a step of placing a spacer rotatably attached to the inside of the outer periphery along the outer periphery, with a reinforcing steel cage installed inside the outer periphery, and rotating the spacer to abut against the reinforcing steel cage; and a step of pouring concrete inside the outer periphery after the spacer has abutted against the reinforcing steel cage, wherein the spacer has upper and lower link portions and a vertical portion rotatably attached to one end of the upper and lower link portions, the other end of the upper and lower link portions is rotatably attached to the outer periphery within a vertical plane, and the upper and lower link portions are rotated within the vertical plane around the other end, causing the spacer to abut against the reinforcing steel cage. The third invention is a method for constructing a structure that is a vertical member, comprising: and an outer periphery having an inner cavity.a step of arranging spacers rotatably attached to the inside of the outer periphery along the outer periphery, with a reinforcing steel cage installed inside the outer periphery, and rotating the spacers to abut against the reinforcing steel cage; and a step of pouring concrete inside the outer periphery after abutting the spacers against the reinforcing steel cage, wherein the spacers have a U-shape in a vertical plane, and upper and lower tips are attached to the outer periphery so as to be rotatable in a horizontal plane, and the spacers abut against the reinforcing steel cage by rotating them in the horizontal plane around the upper and lower tips.

[0010] According to the present invention, spacers are rotatably attached in advance to components that constitute the outer periphery of a structure, such as liner plates, and the position of the reinforcing bar cage is fixed by these spacers. The spacers are deployed from a state in which they are arranged along the outer periphery to abut against the reinforcing bar cage, so they do not interfere with the reinforcing bar cage until then, allowing the reinforcing bar cage to be erected without any problems. Furthermore, by attaching the spacers to the liner plates, there is no need to attach the spacers to the reinforcing bar cage, making it easier and safer to transport the reinforcing bar cage to the site.

[0011] The first invention Space Sa This makes it possible, after erecting the reinforcing bar cage, to raise and lower the wire rods etc. connected to the spacer in advance, and rotate the spacer so that it abuts against the reinforcing bar cage.

[0012] The second invention Space Sa This allows the vertical portion of the spacer to be reliably brought into contact with the reinforcing bar cage.

[0013] The third invention The spacer is , own The weight will not cause it to rotate and the reinforced concrete cage will not come loose.

[0014] The outer periphery is, for example, a liner plate provided on the wall of the borehole. The present invention can be applied to the construction of caisson foundations, etc., in which a liner plate is provided on the wall of a borehole and concrete is poured inside it.

[0015] The fourth invention is a structure having a vertical member. and an outer periphery having an inner cavity. and pouring concrete inside the outer periphery with a reinforcing bar cage installed inside the outer periphery. The spacer is attached to the inside of the outer periphery to fix the position of the reinforcing bar cage inside the outer periphery before pouring the concrete, and is characterized in that it has an arched shape that is convex toward the inside of the outer periphery in a vertical plane, and its upper tip is attached to the outer periphery so as to be rotatable within the vertical plane, so that it can expand from a state that follows the outer periphery to a state that abuts the reinforcing bar cage from the side. The fifth invention is a structure having a vertical member at its outer periphery. and an outer periphery having an inner cavity. and pouring concrete inside the outer periphery with a reinforcing bar cage installed inside the outer periphery, the spacer is attached to the inside of the outer periphery to fix the position of the reinforcing bar cage inside the outer periphery before the concrete is poured, the spacer having upper and lower link portions and a vertical portion rotatably attached to one end of the upper and lower link portions, and the other end of the upper and lower link portions is rotatably attached to the outer periphery so that it can be expanded from a state that is aligned with the outer periphery to a state that is in contact with the reinforcing bar cage. The sixth invention is a method for manufacturing a vertical member structure. and an outer periphery having an inner cavity. and pouring concrete inside the outer periphery with the reinforcing bar cage installed inside the outer periphery. mechanismThe device has a U-shaped configuration in the vertical plane, and the upper and lower ends are attached to the outer periphery so as to be rotatable in the horizontal plane, so that it can be deployed from a state along the outer periphery to a state in contact with the reinforcing bar cage. A spacer and a wire that rotates the spacer until it contacts the reinforcing bar cage. A spacer characterized by mechanism is. [Effects of the Invention]

[0016] The present invention can provide a method for constructing a structure in which a reinforcing bar cage can be suitably fixed using a spacer. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. [Figure 2] FIG. 2 shows a liner plate 2. [Figure 3] A diagram explaining how to construct a deep foundation. [Figure 4] FIG. 2 is a diagram showing spacers 1a and 1b. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0019] [First embodiment] (1. Spacer) 1A and 1B are diagrams showing a spacer 1 according to a first embodiment of the present invention. Fig. 1A is a diagram showing a state in which the spacer 1 is attached to a liner plate 2, and Fig. 1B is a perspective view of the spacer 1.

[0020] As shown in Figure 1(a), the spacer 1 is attached to a liner plate 2 on the wall of a borehole 4, maintains a constant distance between the liner plate 2 and a reinforcing bar cage to be erected in the borehole 4, and fixes the reinforcing bar cage to the center of the borehole 4. In this embodiment, concrete is then poured into the borehole 4 as described below, thereby constructing a caisson foundation for a transmission tower or the like.

[0021] The liner plates 2 are steel members arranged on the periphery of the caisson foundation to retain soil and protect the hole walls. As shown in Figure 2(a), the liner plates 2 are arranged in a line in the circumferential and vertical directions of the borehole 4. The plane of the borehole 4 is circular.

[0022] Each liner plate 2 has a corrugated steel plate 21 with a corrugated vertical cross section. The plane of the corrugated steel plate 21 is arc-shaped, and vertical plates 22 are provided at both ends to join adjacent liner plates 2 in the circumferential direction. The upper and lower ends of the corrugated steel plate 21 serve as horizontal plates 211 to join the upper and lower liner plates 2 together.

[0023] As shown in Figure 2(b), the vertical plates 22 of adjacent liner plates 2 are fastened together using bolts 23 and nuts 24. As shown in Figure 2(c), the horizontal plates 211 of the upper and lower liner plates 2 are fastened together using bolts 26 and nuts 27. This joins the liner plates 2 adjacent to each other in the circumferential direction, and the upper and lower liner plates 2 together.

[0024] As shown in Figure 1(b), the spacer 1 is formed by bending a round piece of steel into a roughly U-shape, and has an overall bow-like shape with bent sections 12, 13 at the top and bottom of a straight section 11. The diameter of the round piece of steel is determined appropriately depending on the number of spacers 1 to be arranged and taking into account the rigidity of the spacer 1, but a diameter of about 6 mm is preferable in terms of workability.

[0025] A pair of left and right straight portions 11 are provided parallel to each other, and a pair of left and right bent portions 12 are also provided parallel to each other so as to extend from the upper end of each straight portion 11. A hole 121 is provided at the tip of each bent portion 12. The tip of each bent portion 12 is wound in a coil shape, and the hole 121 is formed inside the coil. The bent portion 13 is provided in a W shape so as to connect the lower ends of the straight portions 11 together, and a recess 131 is formed in its center.

[0026] The spacers 1 are arranged so that the vertical plates 22 of the circumferentially adjacent liner plates 2 are sandwiched between a pair of bent portions 12, and are attached so as to be rotatable in a vertical plane to bolts 23 that join the upper parts of these vertical plates 22. About five or six liner plates 2 are arranged in a row around the circumferential direction of the borehole 4, and about five or six spacers 1 are provided per row, depending on the number of liner plates 2 in the circumferential direction.

[0027] As shown in Figure 2(d), at the attachment point of the spacer 1, the shaft of the bolt 23 is longer than at other points (see Figure 2(b)), and not only is a nut 24 provided on the tip side of the bolt 23, but a nut 25 is also provided on the head side of the bolt 23.

[0028] The vertical plates 22 of adjacent liner plates 2 in the circumferential direction are fastened together by tightening nuts 24, 25 positioned on either side of these vertical plates 22, but spaces are provided between the head of the bolt 23 and the nut 25, and in the part of the shaft of the bolt 23 protruding from the nut 25, for attaching a spacer 1.

[0029] That is, the tip of the bent portion 12 of the spacer 1 is placed in these spaces, and the shank of the bolt 23 is passed through the hole 121 at the tip of the bent portion 12. This allows the spacer 1 to be rotatably attached to the liner plate 2 in a vertical plane. This embodiment does not require any modification of the liner plate 2, and no special processing or the like is required, which is also preferable in terms of manufacturing the liner plate 2.

[0030] The spacer 1 is arranged along the liner plate 2 due to its own weight, and its bent portion 13 comes into contact with and is locked by the bolt 23 that fastens the lower portions of the vertical plates 22 together, as shown in Fig. 1(a). At this time, the lower portions of the vertical plates 22 are inserted into the recesses 131 of the bent portion 13 (see Fig. 1(b)).

[0031] (2. Construction method of caisson foundation) In this embodiment, as shown in Figure 1(a), spacers 1 are attached when the liner plate 2 is installed, and then wire rods 5 such as wires, chains, reinforcing bars, etc., that are extended downward from the hole opening are connected to the spacers 1. In this embodiment, multiple tiers of spacers 1 are attached at the same horizontal position, and these spacers 1 are connected at different heights to a single wire rod 5.

[0032] Thereafter, as shown in FIG. 3(a), the reinforcing bar cage 3 is lowered by a crane or the like and erected into the borehole 4. The reinforcing bar cage 3 has circumferential reinforcing bars 31 (hoop reinforcing bars) and vertical reinforcing bars 32 (main reinforcing bars). The circumferential reinforcing bars 31 are arranged in multiple rows spaced apart from one another, and the vertical reinforcing bars 32 are attached to the inside of these circumferential reinforcing bars 31. The reinforcing bar cage 3 is pre-assembled in a factory or the like and transported to the site by land transport means such as a truck or trailer, and then inserted into the borehole 4 and installed inside the liner plate 2.

[0033] Thereafter, by pulling the wire 5 up from the hole mouth, multiple spacers 1 in the same horizontal position rotate and rise at the same time, as shown in Figure 3(b), and these spacers 1 unfold, causing their bent portions 13 to laterally abut against the circumferential rebars 31 of the reinforcing bar cage 3. The wire 5 is then fixed in place in the pulled-up position. This causes the distance between the reinforcing bar cage 3 and the liner plate 2 to become constant, and the position of the reinforcing bar cage 3 is fixed in the center of the borehole 4. In this embodiment, in this state, concrete C is poured inside the liner plate 2 as shown in Figure 3(c), thereby constructing a caisson foundation structure.

[0034] As described above, in this embodiment, the spacer 1 is rotatably attached to the liner plate 2 in advance, and after the reinforcing bar cage 3 is erected inside the liner plate 2, the position of the reinforcing bar cage 3 is fixed by the spacer 1. The spacer 1 is arranged along the liner plate 2 when the reinforcing bar cage 3 is erected, and after the reinforcing bar cage 3 is inserted, it unfolds and abuts against the reinforcing bar cage 3, so the spacer 1 does not interfere with the reinforcing bar cage 3 when erecting it and does not hinder the erection of the reinforcing bar cage 3. Furthermore, by attaching the spacer 1 to the liner plate 2 side, there is no need to attach the spacer 1 to the reinforcing bar cage 3, and the dimensions of the reinforcing bar cage 3 do not increase, making it easy and safe to transport the reinforcing bar cage 3 to the site.

[0035] Furthermore, when the spacer 1 is attached to the reinforcing bar cage 3 in advance, it is usually necessary to leave some margin (gap) between the spacer 1 and the liner plate 2 in consideration of ease of construction during erection, and a larger margin is required for large deep foundations. However, in this embodiment, such margin is not necessary, and the error in the erection position of the reinforcing bar cage 3 is reduced to almost zero, and the reinforcing bar cage 3 does not move horizontally after erection.

[0036] Furthermore, in this embodiment, since the spacer 1 can be rotated in a vertical plane, after the reinforcing bar cage 3 has been erected, the wire 5 previously attached to the spacer 1 can be raised and lowered to rotate the spacer 1 and bring it into contact with the reinforcing bar cage 3. In this embodiment, even if the erection of the reinforcing bar cage 3 and the pouring of the concrete C are carried out underwater due to spring water or the like, the spacer 1 can be operated using the wire 5 from the hole opening on the ground.

[0037] However, the present invention is not limited to the above embodiment. For example, the configuration of the spacer 1 is not limited to the above, and it is also possible to form a bow-shaped spacer 1a having a straight portion 11 and curved portions 12 and 13 by bending a steel plate, as shown in the spacer 1a in Fig. 4(a). In this case, too, a hole 121 can be formed at the tip of the curved portion 12, and the shank of a bolt 23 can be passed through this hole to attach the spacer 1a in the same manner as above. The tip of the curved portion 13 is also bent into a W-shape, as above.

[0038] 4(b), it is also possible to form a flat spacer 1b from a single steel plate having a straight portion 11 and curved portions 12, 13. In this case, too, the spacer 1b can be attached in the same manner as above by passing the shank of a bolt 23 through a hole 121 at the tip of the curved portion 12. The spacer 1b can be provided on both sides of the vertical plates 22 of circumferentially adjacent liner plates 2, or can be provided on only one side of the vertical plate 22.

[0039] Furthermore, if the liner plate 2 and spacer 1 corrode in corrosive ground, the corrosion may spread to the reinforcing bar cage 3. Therefore, it is possible to attach a non-metallic part such as a mortar spacer to the part of the spacer 1 that abuts against the reinforcing bar cage 3 (bending part 13), which will prevent corrosion of the reinforcing bar cage 3.

[0040] In this embodiment, the planar surfaces of the borehole 4 and the caisson foundation are circular, but the planar surfaces are not limited to circular shapes. The present invention can also be applied to oval or rectangular shapes. In addition, while this embodiment describes an example of constructing a caisson foundation, the structure to be constructed is not limited to this. For example, with a typical cast-in-place pile, a standpipe may be installed at the mouth of the borehole 4 to prevent landslides near the ground surface. A steel pipe or liner plate larger than the pile diameter is used for the standpipe. In this case, a spacer similar to that used in this embodiment can be used to fix the position of the reinforcing bar cage of the cast-in-place pile.

[0041] Furthermore, depending on the structure, the outer periphery is not limited to a steel liner plate 2 or the like. For example, when constructing a reinforced concrete bridge pier, column, etc., the outer periphery may be a precast buried formwork made of reinforced concrete. In this case, too, when a reinforcing bar cage 3 is installed inside the buried formwork, the present invention can be applied by attaching a spacer 1 to the buried formwork. Also, after the reinforcing bar cage 3 is installed, the buried formwork with the spacer 1 attached in advance can be placed outside the reinforcing bar cage 3. Furthermore, the structure is not limited to vertical members such as caisson foundations, piers, and columns, but may also be a horizontal member.

[0042] Other examples of the present invention will be described below as the second and third embodiments. These embodiments will be described focusing on differences from the first embodiment, and similar features will be denoted by the same reference numerals in the drawings and the like, and a description thereof may be omitted. Furthermore, the configurations described in each embodiment, including the first embodiment, can be combined as necessary.

[0043] [Second embodiment] Figures 5(a) and (b) are diagrams showing the state in which a spacer 10 according to the second embodiment of the present invention is attached to a liner plate 2, and Figures 6(a) and (b) are respectively an oblique view of the spacer 10 and a diagram showing the attachment portion of the spacer 10.

[0044] The spacer 10 of this embodiment differs from the first embodiment in that it includes a link mechanism. That is, in the spacer 10, L-shaped link plates 15, 15 (link portions) are arranged to sandwich the upper end of a vertical plate 14 (vertical portion) from both sides, and the upper end of the vertical plate 14 and one end of the link plates 15, 15 are rotatably connected using bolts 17 and nuts 18. Similarly, L-shaped link plates 16, 16 (link portions) are arranged at the lower end of the vertical plate 14 to sandwich the lower end from both sides, and the lower end of the vertical plate 14 and one end of the link plates 16, 16 are rotatably connected using bolts 17 and nuts 18.

[0045] Holes 151 are provided at the other ends of the link plates 15, 15, and as in the first embodiment, as shown in Figure 6(b), the shanks of the bolts 23 are passed through the holes 151, 151 of the link plates 15, 15 on both sides of the vertical plates 22 of adjacent liner plates 2 in the circumferential direction, so that the link plates 15, 15 are attached to the liner plates 2 so as to be rotatable in the vertical plane.

[0046] Furthermore, in this embodiment, holes 161 are also provided at the other ends of the link plates 16, 16, and as in the example of Figure 6(b), by passing the shanks of the bolts 23 through the holes 161, 161 of the link plates 16, 16 on both sides of the vertical plates 22 of adjacent liner plates 2 in the circumferential direction, the link plates 16, 16 are also attached to the liner plates 2 so that they can rotate in the vertical plane.

[0047] As shown in Figure 5(a), the other ends of the above-mentioned link plates 15, 16 are attached to the upper and lower liner plates 2, which are arranged one row apart, sandwiching the middle liner plate 2 therebetween.

[0048] In this embodiment, by pulling up the wire rods 5 previously attached to the spacers 10 through the hole opening, the spacers 10 rotate and rise as shown in FIG. 5(b), and the spacers 10 unfold so that the vertical plates 14 come into contact with the circumferential reinforcing bars 31 of the cage 3 from the sides, thereby achieving the same effect as in the first embodiment. Also, in this embodiment, it is possible to reliably bring the vertical plates 14 of the spacers 10 into contact with the cage 3. Furthermore, since the vertical plates 14 in FIGS. 5(a) and 5(b) have sufficient length, even if the gap between the upper and lower circumferential reinforcing bars 31 is large, the vertical plates 14 can easily come into contact with the circumferential reinforcing bars 31 when the spacers 10 rise.

[0049] The shape of the spacer 10 is not limited to the example shown in FIG. 6(a). For example, the upper link plate 15 may be replaced with a pair of round steel links 15a as shown in FIG. 6(c). In this case, one end of each link 15a can be wound into a coil shape, with a hole 151 formed inside, and the link can be attached to the shank of a bolt 23, as in the example shown in FIG. 2(d). The other ends of the links 15a are connected in a coil shape, and the connecting portion 152 is placed in a hole 141 in the vertical plate 14. The shank of a bolt 17 can be passed inside the connecting portion 152 to connect the link 15a to the vertical plate 14 with the bolt 17 and nut 18. The same applies to the lower link plate 16.

[0050] The spacer 10 of this embodiment can also be modified to have a shape that functions as a ladder. For example, the spacer 10a in Fig. 7 has bolts 17, etc., that connect the vertical plates 14 and the link plates 15, 16 replaced with cross members 19 that connect adjacent spacers 10a in the circumferential direction, and the vertical plates 14 and the link plates 15, 16 of each spacer 10a are rotatably connected at both ends. The cross members 19 are arc-shaped rods that correspond to the diameter of the reinforcing bar cage 3.

[0051] Spacer 10a is normally arranged along liner plate 2 as shown in Figure 8(a), but link plates 15, 16 have a shape that is the upside-down version of link plates 15, 16 in Figure 6(a), and when used as a ladder, link plates 15, 16 are rotated downward as shown in Figure 8(b). At this time, link plates 15, 16 abut against corrugated steel plates 21 of liner plate 2, stopping the rotation of link plates 15, 16 and fixing spacer 10a in this state. Workers can move up and down by holding onto cross members 19 with their hands or by placing their feet on cross members 19.

[0052] When erecting the reinforcing bar cage 3, the spacer 10a is returned to its initial state shown in Fig. 8(a) beforehand, and after erecting the reinforcing bar cage 3, the link plates 15, 16 are rotated downward again as shown in Fig. 8(c). The vertical plates 14 of the spacer 10a come into contact with the circumferential reinforcing bars 31 of the reinforcing bar cage 3 from the side before the link plates 15, 16 come into contact with the corrugated steel plates 21, thereby maintaining a constant distance between the liner plate 2 and the reinforcing bar cage 3 and fixing the position of the reinforcing bar cage 3 in the center of the borehole 4.

[0053] The link plates 15, 16 can be rotated by connecting wires 5 such as steel rods to the link plates 15, 16 in advance and raising and lowering the wires 5 through holes or the like. When rotating the link plates 15, 16 downward, the wires 5 are simply lowered, and as shown in Figure 8(c), after the vertical plate 14 abuts against the reinforcing bar cage 3, the spacers 10a will not rotate under their own weight and the reinforcing bar cage 3 will not become loose. The cross member 19 can also be provided in the middle of the vertical plate 14, in which case the cross member 19 will not have the function of connecting the vertical plate 14 and the link plates 15, 16.

[0054] [Third embodiment] 9 and 10 are diagrams showing a spacer 100 according to a third embodiment of the present invention. Figures 9(a) and 9(b) are diagrams showing the spacer 100 attached to the liner plate 2, and Figures 10(a) and 10(b) are perspective views of the spacer 100 and diagrams showing the attachment portion of the spacer 100, respectively.

[0055] The spacer 100 of this embodiment differs from the first and second embodiments in that it is attached rotatably within a horizontal plane using bolts 26 that fasten the horizontal plates 211 of the upper and lower liner plates 2 together.

[0056] A plurality of spacers 100 are arranged at intervals in the circumferential direction as shown in Fig. 11. The spacers 100 are also arranged in multiple vertical tiers at intervals of about several meters in the vertical direction.

[0057] 10(a), the spacer 100 is formed by bending a round piece of steel, and has an overall U-shape with horizontal sections 120 and 130 above and below a vertical section 110. At the tips of the horizontal sections 120 and 130, holes are formed inside by winding both ends of the round piece of steel into a coil.

[0058] The upper horizontal portion 120 of the spacer 100 is attached using a bolt 26 that fastens the horizontal plate 211 of the upper liner plate 2 to the horizontal plate 211 of the middle liner plate 2. As shown in FIG. 10(b), this bolt 26 is attached facing upward, and the tip of the shaft of the bolt 26 that protrudes above the nut 27 is passed through a hole at the tip of the horizontal portion 120.

[0059] On the other hand, the lower horizontal portion 130 of the spacer 100 is attached using a bolt 26 that fastens the horizontal plate 211 of the middle liner plate 2 to the horizontal plate 211 of the lower liner plate 2. This bolt 26 is attached facing downward, and the attachment location of the horizontal portion 130 has a configuration that is the upside down of Figure 10(b). That is, the tip of the shaft of the bolt 26 that protrudes below the nut 27 is passed through a hole at the tip of the lower horizontal portion 130.

[0060] This allows the spacer 100 to be attached to the liner plate 2 so as to be rotatable in a horizontal plane. In this embodiment, the spacer 100 is attached when the liner plate 2 is installed, and the reinforcing bar cage 3 is erected in the borehole 4 with the spacer 100 positioned along the liner plate 2 as shown in Figure 9(a).

[0061] Thereafter, the spacer 100 is rotated in a horizontal plane, and as shown in Fig. 9(b), the spacer 100 is unfolded so that the vertical portion 110 comes into contact with the circumferential reinforcing bars 31 of the reinforcing bar cage 3 from the side, thereby achieving the same effect as in the first embodiment. In addition, the spacer 100 will not rotate due to its own weight, causing the reinforcing bar cage 3 to become loose.

[0062] In this embodiment, the spacer 100 is rotated using the wire 5. That is, the wire 5 extending downward from the hole opening is attached to the vertical portion 110 of the spacer 100 via a pulley 6 as shown in FIG. 10(a). By pulling up the wire 5, the spacer 100 rotates in a horizontal plane as shown in FIG. 9(b). Furthermore, as shown in FIG. 11, if multiple spacers 100 arranged at intervals in the circumferential direction are connected with a connecting member 7 such as a string, when one spacer 100 rotates in the above procedure, the other spacers 100 also rotate, and multiple spacers 100 can be rotated simultaneously.

[0063] The spacer 100 is not limited to being formed by bending round steel bars, but may also be formed by bending a steel plate into a U-shape as shown in Figure 12, in which case the spacer 100a can also be attached to the liner plate 2 in the same manner as described above by passing the shank of the bolt 26 through the holes 121a, 131a provided at the tips of the horizontal portions 120, 130.

[0064] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art can conceive of various modifications or alterations within the scope of the technical ideas disclosed herein, and it is understood that these modifications also fall within the technical scope of the present invention. [Explanation of symbols]

[0065] 1, 1a, 1b, 10, 10a, 100, 100a: Spacer 2: Liner plate 3: Reinforced concrete cage 4: Borehole 5:Wire rod C: Concrete

Claims

1. A method of constructing a structure that is a vertical member, comprising: providing a periphery of the structure, the periphery having an internal cavity; A process in which a spacer rotatably attached to the inside of the outer periphery is arranged along the outer periphery, and a reinforcing bar cage is installed inside the outer periphery, and then the spacer is rotated to abut against the reinforcing bar cage; a step of placing the spacer in contact with the reinforcing bar cage, and then pouring concrete inside the outer periphery; and the spacer has an arched shape that is convex toward the inside of the outer periphery in a vertical plane, and an upper tip of the spacer is attached to the outer periphery so as to be rotatable within the vertical plane; A method for constructing a structure, characterized in that the spacer is rotated in a vertical plane around the upper tip, causing the spacer to abut against the reinforcing bar cage.

2. A method of constructing a structure that is a vertical member, comprising: providing a periphery of the structure, the periphery having an internal cavity; A process in which a spacer rotatably attached to the inside of the outer periphery is arranged along the outer periphery, and a reinforcing bar cage is installed inside the outer periphery, and then the spacer is rotated to abut against the reinforcing bar cage; a step of placing the spacer in contact with the reinforcing bar cage, and then pouring concrete inside the outer periphery; and The spacer is The upper and lower links, a vertical portion rotatably attached to one end of the upper and lower link portions; the other end of each of the upper and lower link portions is attached to the outer periphery so as to be rotatable within a vertical plane, A method for constructing a structure, characterized in that the spacer abuts against the reinforcing bar cage by rotating the upper and lower link portions in a vertical plane around the other end.

3. A method of constructing a structure that is a vertical member, comprising: providing a periphery of the structure, the periphery having an internal cavity; A process in which a spacer rotatably attached to the inside of the outer periphery is arranged along the outer periphery, and a reinforcing bar cage is installed inside the outer periphery, and then the spacer is rotated to abut against the reinforcing bar cage; a step of placing the spacer in contact with the reinforcing bar cage, and then pouring concrete inside the outer periphery; and The spacer has a U-shape in a vertical plane, and upper and lower ends are attached to the outer periphery so as to be rotatable in a horizontal plane, A method for constructing a structure, characterized in that the spacer is rotated in a horizontal plane around the upper and lower tips, causing the spacer to abut against the reinforcing bar cage.

4. A spacer for fixing the position of the reinforcing bar cage inside the periphery of a vertical structure before pouring concrete when constructing the structure by a step of providing the periphery with a cavity on the inside and a step of pouring concrete inside the periphery with a reinforcing bar cage installed inside the periphery, the spacer being attached to the inside of the periphery and used to fix the position of the reinforcing bar cage inside the periphery before pouring concrete, A spacer characterized in that it has an arched shape in a vertical plane that convex toward the inside of the outer periphery, and its upper tip is rotatably attached to the outer periphery within the vertical plane, so that it can expand from a state that follows the outer periphery to a state that abuts the reinforcing bar cage from the side.

5. A spacer for fixing the position of the reinforcing bar cage inside the periphery of a vertical structure before pouring concrete when constructing the structure by a step of providing the periphery with a cavity on the inside and a step of pouring concrete inside the periphery with a reinforcing bar cage installed inside the periphery, the spacer being attached to the inside of the periphery and used to fix the position of the reinforcing bar cage inside the periphery before pouring concrete, The upper and lower links, a vertical portion rotatably attached to one end of the upper and lower link portions; The other ends of the upper and lower link portions are rotatably attached to the outer periphery in a vertical plane, so that the spacer can be expanded from a state that is aligned with the outer periphery to a state that is in contact with the reinforcing bar cage.

6. A spacer mechanism for fixing the position of the reinforcing bar cage inside the periphery of a vertical structure before pouring concrete, the spacer mechanism being attached to the inside of the periphery when constructing the structure by a step of providing the periphery with a cavity on the inside and a step of pouring concrete inside the periphery with a reinforcing bar cage installed inside the periphery, a spacer having a U-shape in a vertical plane, with upper and lower ends attached to the outer periphery so as to be rotatable in a horizontal plane, so that the spacer can be expanded from a state following the outer periphery to a state in contact with the reinforcing bar cage; a wire rod that rotates the spacer until it abuts against the reinforcing bar cage; A spacer mechanism comprising:

Images