Method for assembling steel bar
By assembling the steel bars into an arc-shaped column structure and fixing the main column with U-shaped bolts, the problems of high labor intensity, long time and the main column cannot pass through the frame hole in the traditional reinforcement method are solved, and the reinforcement process is simplified and the efficiency is improved.
Patent Information
- Application Number
- JP2023145105
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-09-07
- Publication Date
- 2025-03-19
AI Technical Summary
In the reinforcement of large structures, traditional methods require the use of cranes to lift and reinforce the main columns multiple times, resulting in high labor intensity, long time and the possibility of the main columns not being able to pass through the frame hole.
The method of using arc-shaped steel bar units is used to assemble the steel bars into arc-shaped columnar structures and fix the main columns with U-shaped bolts, which reduces the difficulty of manufacturing and transportation of the frame and simplifies the reinforcement process.
It effectively reduces labor intensity and construction time, simplifies the reinforcement process, and solves the problem that the rear end of the main column cannot pass through the frame hole.
Smart Images
Figure 2025038472000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a method for assembling reinforcing bars. [Background technology]
[0002] Conventionally, in the reinforcement work of large structures such as the foundation of an onshore wind turbine, a large number of column main bars are lifted one by one by a crane and arranged, and reinforcing bars (hoops) are arranged so as to surround the arranged large number of column main bars. In the reinforcement work in which a large number of column main bars are lifted one by one by a crane and arranged, it takes time and costs, and requires skilled techniques, so that a shortage of human resources can be a problem. In response to this, Patent Document 1 discloses a method of assembling reinforcing bars in which a frame plate having a large number of holes formed in accordance with the intervals between the columns is installed horizontally, the column main bars are inserted and fixed into each of the many holes in the frame plate, and the reinforcing bars are arranged so as to surround the large number of column main bars fixed to the frame plate (see, for example, Patent Document 1). Reinforcing bar units assembled in this way are manufactured, for example, in a factory, transported to the site, and installed at the installation position. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 63-47469 Summary of the Invention [Problem to be solved by the invention]
[0004] However, in the case of a large structure, the frame plates also become large, which poses the problem of the labor required for producing and transporting the frame plates. There is also the problem that the work of passing the column main bars through the holes in the frame plate is large-scale, and requires a lot of labor and time. Also, for example, there is a possibility that the column main bars that have been processed, such as having bent parts at the ends, cannot be passed through the holes in the frame plate.
[0005] Therefore, an object of the present invention is to provide a method for assembling reinforcing bars that can reduce labor and shorten construction time. [Means for solving the problem]
[0006] In order to achieve the above object, the reinforcing bar assembly method of the present invention comprises: an arc-shaped reinforcing bar unit production process for assembling reinforcing bars into a columnar shape having a cross-sectional shape of an arc to produce a plurality of arc-shaped reinforcing bar units; and a connection process for connecting a plurality of the arc-shaped reinforcing bar units in the circumferential direction of the arc to produce a cylindrical reinforcing bar unit, wherein the arc-shaped reinforcing bar unit comprises a plurality of arc-shaped arc-shaped frame portions, a plurality of main reinforcements fixed to the arc-shaped frame portion, and a plurality of reinforcing bars installed on the outer periphery of the plurality of main reinforcements, and the arc-shaped frame portion has a plurality of holes formed at intervals in the circumferential direction into which threaded portions of U-shaped bolts for fixing the main reinforcements are inserted, and the arc-shaped reinforcing bar unit production process comprises connecting a plurality of the arc-shaped frame portions together in a manner such that the central axis of the arc extends in a first horizontal direction. the arc-shaped frame part is temporarily fixed in the first horizontal direction with a gap therebetween in the same orientation with the axis and the outer periphery side facing up; a main reinforcement installation process for fixing the multiple main reinforcements to the outer periphery of the temporarily fixed arc-shaped frame part with a gap therebetween in a direction extending in the first horizontal direction; a reinforcing bar installation process for installing the reinforcing bars on the outer periphery of the multiple main reinforcements fixed to the arc-shaped frame part; and a temporary fixation releasing process for releasing the temporary fixation of the arc-shaped frame part after the reinforcing bar installation process, wherein in the main reinforcement installation process, the main reinforcements are arranged on the outer periphery or inner periphery of the arc-shaped frame part, the threaded portions of the U-shaped bolts are passed through the holes of the arc-shaped frame part, the main reinforcements are sandwiched between the U-shaped bolts and the arc-shaped frame part, and nuts are fixed to the threaded portions of the U-shaped bolts.
[0007] In the present invention, rebars are assembled into a columnar shape with a cross section of an arc to produce an arc-shaped rebar unit, and a plurality of the produced arc-shaped rebar units are connected to produce a cylindrical rebar unit. Therefore, the frame part for fixing the main reinforcement can be an arc-shaped frame part corresponding to the arc of the arc-shaped rebar unit, rather than a single annular frame part corresponding to the cylinder of the cylindrical rebar unit. Therefore, compared to the case where an annular frame part is used, the shape of each frame part (arc-shaped frame part) can be made smaller, the labor required for producing and transporting the frame part can be reduced, and the construction period can be shortened. In the present invention, if the reinforcing bar units are manufactured in advance at a factory or the like, they can be transported to the site and installed in the desired location. This eliminates the need for the conventional work of hoisting the main reinforcement bars with a crane and arranging them on-site, thereby reducing labor and shortening the construction period. In the present invention, since the main reinforcement is fixed to the arc-shaped frame by the U-shaped bolt, it is easier to fix the main reinforcement to the arc-shaped frame compared to the case where the main reinforcement is fixed to the frame by passing it through a hole formed in the frame. Also, in the present invention, even if the main reinforcement cannot be passed through a hole formed in the frame, such as when the end of the main reinforcement is bent, the main reinforcement can be easily fixed to the arc-shaped frame.
[0008] In addition, in the reinforcing bar assembly method of the present invention, in the connecting process, one of the multiple arc-shaped reinforcing bar units is placed on the floor surface with the central axis of the arc extending in the first horizontal direction and the inner periphery facing upward, and another arc-shaped reinforcing bar unit is placed on top of the arc-shaped reinforcing bar unit placed on the floor surface with the central axis of the arc extending in the first horizontal direction and the inner periphery facing downward, and the ends of the arc-shaped frame portions of each of the arc-shaped reinforcing bar units placed above and below are connected to connect the multiple arc-shaped reinforcing bar units into a cylindrical shape.
[0009] With this configuration, the arc-shaped reinforcing bar units that are connected from above can be placed on top of the arc-shaped reinforcing bar units installed on the floor in the same position as when they were manufactured, making it easy to connect the arc-shaped reinforcing bar units to each other. Even in the case of tall reinforcing bar units, the arc-shaped reinforcing bar units are laid flat, so the arc-shaped frame parts can be connected to each other at a low position, making the work easier. Effect of the Invention
[0010] According to the present invention, it is possible to reduce labor and shorten construction time. [Brief description of the drawings]
[0011] [Figure 1] 1 is a cross-sectional view of a structure in which reinforcing bar units are installed, the reinforcing bar units being assembled by a reinforcing bar assembly method according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] This is a horizontal cross section of a reinforcing bar unit. [Figure 4] FIG. [Diagram 5] FIG. 2 is a side view of a column main reinforcement. [Figure 6] FIG. 13 is a diagram showing column main reinforcement fixed to a circular arc-shaped frame portion with a U-shaped bolt. [Figure 7] FIG. [Figure 8] FIG. 13 is a diagram showing the main reinforcement installation process. [Figure 9] FIG. 13 is a diagram showing the state after the main reinforcement installation process is completed. [Figure 10] FIG. 13 is a diagram showing the reinforcing bar installation process. [Figure 11] FIG. [Figure 12] FIG. 4 is a perspective view showing a joint portion of the arc-shaped frame portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] Hereinafter, a method for assembling a reinforcing bar according to an embodiment of the present invention will be described with reference to Figs. The reinforcing bar assembly method according to the present embodiment is a method for assembling reinforcing bars in a large structure, and is a method for assembling a reinforcing bar unit 1 provided in the center of a foundation 13 of an onshore wind turbine shown in FIG. 1. As shown in FIGS. 2 and 3, the reinforcing bar unit 1 is cylindrical and installed with its axis extending vertically. The reinforcing bar unit 1 is manufactured by connecting a first unit 11 and a second unit 12, each of which is made by assembling reinforcing bars into a column shape having a semicircular cross section, into a cylindrical shape. The first unit 11 and the second unit 12 have the same shape. The first unit 11 and the second unit 12 correspond to the "arc-shaped reinforcing bar unit" in the claims. In the explanation of the reinforcing bar unit 1, the first unit 11, and the second unit 12, the direction in which the axis of the reinforcing bar unit 1 extends is referred to as the axial direction, and the direction in which the reinforcing bar unit 1 rotates around the axis is referred to as the circumferential direction. The side facing the axis in the direction perpendicular to the axis (radial direction) (inner side in the radial direction) is referred to as the inner circumference side, and the side facing away from the axis (outer side in the radial direction) is referred to as the outer circumference side.
[0013] Each of the first unit 11 and the second unit 12 has an arc-shaped frame portion 2, a main bar 3, and a reinforcing bar 4. The arc-shaped frame portion 2 is formed in a semicircular arc shape and extends along the circumferential direction of the first unit 11 and the second unit 12. A plurality of arc-shaped frame portions 2 are provided at intervals in the vertical direction. In this embodiment, two arc-shaped frame portions 2 are provided at intervals in the vertical direction. The arc-shaped frame portion 2 is made of steel. The main bars 3 extend in the axial direction of the first unit 11 and the second unit 12, i.e., in the vertical direction, and are fixed in large numbers to the outer periphery of the arc-shaped frame portion 2 at intervals in the circumferential direction. The main bars 3 are fixed to the arc-shaped frame portion 2 by U-shaped bolts 5 (see FIG. 3). The reinforcing bar 4 extends in the circumferential direction of the first unit 11 and the second unit 12 and is provided on the outer periphery of the many main bars 3 fixed to the arc-shaped frame portion 2.
[0014] As shown in FIG. 4, the arcuate frame portion 2 is formed with a plurality of holes 21 over the entire circumferential direction, into which threaded portions 51, 51 of the U-shaped bolt 5 (see FIG. 6) are inserted. As shown in FIG. 5, the main reinforcement 3 has a straight portion 31 extending in a straight line in the vertical direction, an upper bent portion 32 continuing to the upper end of the straight portion 31, and a lower bent portion 33 continuing to the lower end of the straight portion 31. The upper bent portion 32 is bent 180° relative to the straight portion 31. The lower bent portion 33 is bent 90° relative to the straight portion 31. The straight portion 31 of the main reinforcement 3 is disposed on the outer periphery of the arc-shaped frame portion 2. As shown in FIG. 6, the main reinforcement 3 is disposed between the adjacent holes 21, 21 in the arc-shaped frame portion 2. The threaded portions 51, 51 of the U-shaped bolt 5 are inserted into the holes 21, 21 of the arc-shaped frame portion 2 located on both sides of the main reinforcement 3 in the circumferential direction from the outer periphery of the arc-shaped frame portion 2 and penetrate therethrough. The straight portion 31 of the main reinforcement 3 is sandwiched between the middle portion 53 of the U-shaped bolt 5 and the arc-shaped frame portion 2. Nuts 52 are fastened to the threaded portions 51, 51 of the U-shaped bolt 5 from the inner periphery of the arc-shaped frame portion 2, thereby fixing the main reinforcement 3 to the arc-shaped frame portion 2. Both end portions (straight portions) of the U-shape of the U-shaped bolt 5 are referred to as threaded portions 51, 51, and the curved portion between the threaded portions 51, 51 in the middle of the U-shape is referred to as middle portion 53.
[0015] The straight portion 31 of the main reinforcement 3 may be disposed on the inner periphery side of the arc-shaped frame portion 2. In such a case, the threaded portions 51, 51 of the U-shaped bolt 5 are inserted into the holes 21, 21 of the arc-shaped frame portion 2 from the inner periphery side of the arc-shaped frame portion 2, respectively, and the straight portion 31 of the main reinforcement 3 is sandwiched between the middle portion 53 of the U-shaped bolt 5 and the arc-shaped frame portion 2. The main reinforcement 3 is fixed to the arc-shaped frame portion 2 by fastening nuts 52 to the threaded portions 51, 51 of the U-shaped bolt 5 from the outer periphery side of the arc-shaped frame portion 2.
[0016] As shown in Fig. 3, the reinforcing bars 4 are curved in an arc shape with a central angle greater than 180°. The reinforcing bars 4 protrude outward in the circumferential direction from the main bars 3 at the circumferential end positions among the many main bars 3 having at least one end fixed to the arc-shaped frame portion 2. The end positions of the reinforcing bars 4 of the first unit 11 are indicated by reference characters 4a, 4a, and the end positions of the reinforcing bars 4 of the second unit 12 are indicated by reference characters 4b, 4b. The reinforcing bars 4 are provided at intervals in the axial direction of the first unit 11 and the second unit 12, i.e., in the vertical direction.
[0017] The first unit 11 and the second unit 12 are connected at the ends 2a, 2b of their respective arc-shaped frame portions 2 to form a cylindrical reinforcing bar unit 1. The reinforcing bars 4 of the first unit 11 and the reinforcing bars 4 of the second unit 12 are joined by a lap joint 41 in which the respective end sides are overlapped and bound together.
[0018] A method for assembling the reinforcing bar unit 1 will be described. First, the first unit 11 is manufactured (arc-shaped reinforcing bar unit manufacturing process). 7, first unit 11 and second unit 12 are manufactured in such a manner that the axial direction of first unit 11 and second unit 12 is in a first horizontal direction (the direction of arrow A in FIG. 7) rather than in a vertical direction. 7, the two arc-shaped frame portions 2 of the first unit 11 are temporarily fixed to the pedestal 6 (temporary fixing process). The two arc-shaped frame portions 2, 2 are temporarily fixed to the pedestal 6 with a gap therebetween in the first horizontal direction in such a manner that the central axes of the arcs extend coaxially in the first horizontal direction, the outer periphery side is the upper side, and one end 2a1 in the circumferential direction is positioned higher than the other end 2a2. The mount 6 has a first mount 61 for fixing one circumferential end 2a1 of the arc-shaped frame portion 2, a second mount 62 for fixing the other end 2a2, and a third mount 63 for fixing the circumferential middle portion. The first mount 61 is installed at a higher position than the second mount 62. For example, the first frame 61 and the second frame 62 are each made of steel material having the same length as the height dimension of the reinforcing bar unit 1. The first frame 61 and the second frame 62 are each installed in a direction extending in a first horizontal direction. The second frame 62 is installed on the floor of a factory where the reinforcing bar units 1 are manufactured. The first frame 61 is installed at a predetermined height above the factory floor via a height adjustment member 611. The first frame 61 and the second frame 62 are provided with fixing plates 64 that protrude upward and can be used to fix both circumferential ends of the arc-shaped frame portion 2 with fixing tools such as a clamp or a manipulator. The third frame 63 is a columnar steel material whose lower end is supported on the factory floor. The third frame 63 has an upper end on which the middle part in the circumferential direction of the arc-shaped frame portion 2 is placed and fixed.
[0019] Next, the main reinforcement 3 is fixed to the outer periphery of the two arc-shaped frame parts 2 fixed to the frame 6 (main reinforcement installation process). As shown in FIG. 8, the main reinforcement 3 is placed on the outer periphery of the two arc-shaped frame parts 2 fixed to the frame 6, and the main reinforcement 3 is fixed to the arc-shaped frame part 2 with a U-shaped bolt 5. At this time, as shown in FIG. 6, the main reinforcement 3 is placed between the adjacent holes 21, 21 in the arc-shaped frame part 2. The threaded parts 51, 51 of the U-shaped bolt 5 are inserted and penetrated into each of these holes 21, 21 from the outer periphery side of the arc-shaped frame part 2, and the main reinforcement 3 is sandwiched between the middle part 53 of the U-shaped bolt 5 and the arc-shaped frame part 2. Nuts 52, 52 are fastened to the threaded parts 51, 51 of the U-shaped bolt 5 from the inner periphery side of the arc-shaped frame part 2. As shown in FIG. 9, a plurality of main reinforcements 3 are fixed with the U-shaped bolt 5 over the entire circumferential direction of the arc-shaped frame part 2.
[0020] In addition, when the straight portion 31 of the main reinforcement 3 is arranged on the inner side of the arc-shaped frame portion 2, the threaded portions 51, 51 of the U-shaped bolt 5 are inserted into and penetrate the holes 21, 21 from the inner side of the arc-shaped frame portion 2, the main reinforcement 3 is sandwiched between the middle portion 53 of the U-shaped bolt 5 and the arc-shaped frame portion 2, and nuts 52, 52 are fastened to the threaded portions 51, 51 of the U-shaped bolt 5 from the outer side of the arc-shaped frame portion 2.
[0021] Next, reinforcing bars 4 are provided around the multiple main bars 3 fixed to the arc-shaped frame portion 2 (reinforcing bar installation process). As shown in Fig. 10, one circumferential end 4a1 of the reinforcing bars 4 is caused to protrude circumferentially outward from one end 2a1 of the arc-shaped frame portion 2. Because the first frame 61 is located above the floor surface, the workability is improved by causing the end of the reinforcing bars 4 on the first frame 61 side to protrude. The first unit 11 is assembled by arranging the reinforcing bars 4.
[0022] Next, the arcuate frame portion 2 is removed from the mount 6 to release the temporary fixation (temporary fixation releasing step). The first unit 11 removed from the frame 6 is lifted by an overhead crane or the like and temporarily placed in another location. At this time, the first unit 11 is temporarily placed with its axial direction horizontal and its inner circumference side facing upward, as shown in Fig. 11. A support member for supporting the first unit 11 is appropriately installed.
[0023] Next, the second unit 12 is manufactured in the same manner as the first unit 11.
[0024] Next, the first unit 11 and the second unit 12 are connected (connection process). After the manufactured second unit 12 is removed from the frame 6, the second unit 12 is lifted by an overhead crane or the like and moved onto the first unit 11 that is temporarily placed (see FIG. 11). The second unit 12 is moved onto the first unit 11 with the inner circumference side facing downward. With the second unit 12 still in the lifted state by the overhead crane, the end 2a of the arc-shaped frame portion 2 of the first unit 11 and the end 2b of the arc-shaped frame portion 2 of the second unit 12 are connected by a backing plate 23 and a bolt 24 as shown in FIG. 12. As shown in FIG. 3, the reinforcing bars 4 of the first unit 11 and the reinforcing bars 4 of the second unit 12 that overlap each other are tied together by a lap joint 41. In this manner, the reinforcing bar unit 1 is produced.
[0025] The manufactured reinforcing bar unit 1 is transported to the site and installed at the installation location. If the reinforcing bar unit 1 is large and difficult to transport, the first unit 11 and the second unit 12 may be manufactured and transported to the site without being connected, and the first unit 11 and the second unit 12 may be connected at the site.
[0026] Next, the operation and effect of the reinforcing bar assembling method according to this embodiment will be described. In the reinforcing bar assembly method according to this embodiment, the reinforcing bars are assembled into a columnar shape having a cross-sectional shape of a circular arc to produce the first unit 11 and the second unit 12, and the produced second unit 12 and second unit 12 are connected to produce the cylindrical reinforcing bar unit 1. Therefore, the frame part for fixing the multiple main reinforcements 3 can be an arc-shaped frame part 2 corresponding to the arcs of the first unit 11 and the second unit 12, rather than a single annular frame part corresponding to the cylinder of the cylindrical reinforcing bar unit 1. Therefore, compared to the case where an annular frame part is used, the shape of each frame part (arc-shaped frame part 2) can be made smaller, the labor required for producing and transporting the frame part can be reduced, and the construction period can be shortened.
[0027] In the reinforcing bar assembly method according to this embodiment, if the reinforcing bar unit 1 is fabricated in advance at a factory or the like, it is sufficient to transport the reinforcing bar unit 1 to the site and install it at the installation location. This eliminates the need to hoist the main column reinforcement bars with a crane and arrange them on-site, as was previously done, thereby reducing labor and shortening the construction period.
[0028] In the reinforcing bar assembling method according to this embodiment, the main reinforcement 3 is fixed to the arc-shaped frame portion 2 by the U-shaped bolts 5, so the main reinforcement 3 can be fixed to the arc-shaped frame portion 2 more easily than in the case where the main reinforcement 3 is fixed to the frame portion by passing the main reinforcement through holes formed in the frame portion. Also, even in the case where the main reinforcement 3 cannot be passed through holes formed in the frame portion, such as when the ends of the main reinforcement 3 are processed to have upper bends 32 and lower bends 33, as in this embodiment, the main reinforcement 3 can be easily fixed to the arc-shaped frame portion 2.
[0029] In the connecting step of the reinforcing bar assembly method according to the present embodiment, the first unit 11 is placed on the floor with the inner circumferential side facing upward, the second unit 12 is placed on the first unit 11 with the inner circumferential side facing downward, and the ends 2a, 2b of the arc-shaped frame parts 2 of the first unit 11 and the second unit 12 arranged vertically are connected to each other to manufacture a cylindrical reinforcing bar unit 1. This allows the second unit 12 to be connected from above to be placed on the first unit 11 placed on the floor in the same position as when it was manufactured, so that the arc-shaped reinforcing bar units can be easily connected to each other. Furthermore, even in the case of a tall reinforcing bar unit 1, the first unit 11 and the second unit 12 are in a horizontal position, so that the arc-shaped frame part 2 of the first unit 11 and the arc-shaped frame part 2 of the second unit 12 can be connected at a low position, which improves workability.
[0030] Although an embodiment of the reinforcing bar assembly method according to the present invention has been described above, the present invention is not limited to the above embodiment and can be modified as appropriate without departing from the spirit of the present invention. For example, in the above embodiment, the reinforcing bar unit 1 is in the form of a first unit 11 and a second unit 12 connected together, each having a semicircular cross section, but it may also be in the form of three or more arc-shaped reinforcing bar units connected together, each of which is made by assembling reinforcing bars into a columnar shape having an arc cross section. [Explanation of symbols]
[0031] 1 Reinforcement unit 2 Arc-shaped frame 2a,2b end 3 Main reinforcement 4 Reinforcement 5 U-bolt 6 Mounting stand 11 First unit (arc-shaped rebar unit) 12 2nd unit (arc-shaped reinforcing bar unit) 21 Hole 51 Screw part 52 Nut 53 Middle section
Claims
1. a circular-arc reinforcing bar unit manufacturing process for assembling reinforcing bars into a columnar shape having a circular arc cross section to manufacture a plurality of circular-arc reinforcing bar units; A connecting process of connecting a plurality of the arc-shaped reinforcing bar units in a circumferential direction of the arc to produce a cylindrical reinforcing bar unit, The arc-shaped reinforcing bar unit is A plurality of arc-shaped frame portions; A plurality of main reinforcements fixed to the arc-shaped frame portion; A plurality of reinforcing bars are provided on the outer peripheral side of the plurality of main reinforcements, The arc-shaped frame portion has a plurality of holes, into which threaded portions of U-shaped bolts for fixing the main reinforcement are inserted, spaced apart in the circumferential direction; The arc-shaped reinforcing bar unit manufacturing process includes: a temporary fixing process in which the plurality of arc-shaped frame portions are temporarily fixed at intervals in the first horizontal direction in the same orientation with the central axis of the arc extending in the first horizontal direction and the outer circumferential side facing upward; a main reinforcement installation process for fixing the plurality of main reinforcements to the outer periphery of the temporarily fixed arc-shaped frame portion at intervals in a circumferential direction of the arc in a direction extending in the first horizontal direction; a reinforcing bar installation process in which the reinforcing bars are installed on the outer circumferential side of the plurality of main bars fixed to the arc-shaped frame portion; A temporary fixation release process for releasing the temporary fixation of the arc-shaped frame portion after the reinforcing bar installation process, In the main reinforcement installation process, The main reinforcement is disposed on the outer circumferential side or the inner circumferential side of the arc-shaped frame portion, The threaded portion of the U-shaped bolt is passed through the hole portion of the arc-shaped frame portion, and the main reinforcement is sandwiched between the U-shaped bolt and the arc-shaped frame portion. A method of assembling reinforcing bars by fixing a nut to the threaded portion of the U-shaped bolt.
2. In the connecting step, One of the plurality of arc-shaped reinforcing bar units is installed on a floor surface with a central axis of the arc extending in the first horizontal direction and an inner circumferential side facing upward; On the arc-shaped reinforcing bar unit installed on the floor surface, another arc-shaped reinforcing bar unit is placed in such a manner that the central axis of the arc extends in the first horizontal direction and the inner periphery side faces downward; 2. A method for assembling reinforcing bars according to claim 1, wherein the ends of the arc-shaped frame portions of the arc-shaped reinforcing bar units arranged vertically are connected to each other to connect a plurality of the arc-shaped reinforcing bar units into a cylindrical shape.
Citation Information
Patent Citations
Method of construction for preassembly of column reinforcement
JP1988047469A