Reinforcing steel bar cage and manufacturing method

Abstract

To provide a reinforcing steel bar cage and a manufacturing method, which enable transport in large numbers even by a vehicle with a small loading space and which allows a completed reinforcing steel bar cage to be manufactured relatively easily and accurately on site.SOLUTION: A reinforcing steel bar cage 1 is placed in a surrounding space S formed around a pile head 21 of a foundation pile 2 buried in the ground, and a hardened body cast into the surrounding space S hardens over time to form a reinforcing steel bar hardened body part of the pile head 21. The reinforcing steel bar cage 1 is large enough to be horizontally spaced apart from an outer circumferential surface of the pile head 21 and positioned around the outer circumferential surface, and is provided with surrounding reinforcement bars 10 that form a reinforcement form that becomes higher in the height direction of the pile head 21, while forming a transport form in which the height is reduced. The surrounding reinforcement bars 10 are, for example, composed of spiral reinforcement bars 12.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a reinforcing steel cage for reinforcing the head portion of a foundation pile and a manufacturing method for manufacturing a completed reinforcing steel cage on site using this reinforcing steel cage.

Background Art

[0002] Conventionally, a construction method has been put into practical use in which the surrounding ground of a foundation pile using a precast pile is excavated and the head portion of the pile is reinforced using a brittle material such as concrete. In such a construction method, as the horizontal displacement of the foundation pile increases during a great earthquake or the like, large stresses are generated inside the reinforcing body around the foundation pile, and as a result, it is considered that cracks and damage occur.

[0003] Patent Document 1 discloses a steel cage for reinforcing the head portion of a foundation pile. This steel cage is formed in a cylindrical cage shape from, for example, a plurality of bar-shaped main reinforcing bars extending in the axial direction and ring-shaped hoop reinforcing bars arranged in a horizontal plane. And a guiding fitting for aligning the axial centers of the foundation pile and the steel cage is arranged in this steel cage. This guiding fitting is composed of an annular member having an inner diameter slightly larger than the outer diameter of the foundation pile and a position holding member for holding this annular member at the central position of the steel cage.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, since such a steel bar cage has a bulky cylindrical shape and is transported to the site, it is necessary to use a vehicle with a large loading space, which has the drawback of high transportation costs. On the other hand, transporting the constituent materials of the steel bar cage to the site and fabricating the steel bar cage from scratch at the site is inefficient. In addition, there is a risk of occurrence of reinforcement errors, etc., so separate efforts are required to ensure the construction quality such as reinforcement inspection.

[0006] In view of the above circumstances, an object of the present invention is to provide a reinforcing steel bar cage and a manufacturing method thereof that can be transported in large numbers even by a vehicle with a small loading space and that can relatively easily and accurately fabricate a completed reinforcing steel bar cage at the site.

Means for Solving the Problem

[0007] The reinforcing steel bar cage according to the present invention is arranged in a surrounding space formed around the head portion of a foundation pile embedded in the ground, and is a reinforcing steel bar cage that forms a hardened body portion of the reinforcing steel bars for the head portion of the pile by a hardened body that hardens over time and is placed in the surrounding space, It has a size that is spaced horizontally from the outer peripheral surface of the head portion of the foundation pile and is located around the outer peripheral surface, and is provided with surrounding bars that form a reinforcement time form that becomes higher in the height direction of the head portion while forming a transportation time form in which this height is lowered.

[0008] With the above configuration, the surrounding bars form a reinforcement time form that becomes higher in the height direction of the head portion while forming a transportation time form in which this height is lowered. Therefore, it is possible to transport a large number even by a vehicle with a small loading space. In addition, by setting the surrounding bars to the reinforcement time form at the site, a completed reinforcing steel bar cage can be relatively easily and accurately fabricated at the site.

[0009] The surrounding reinforcement bars may have a spiral portion whose height increases by pulling the uppermost portion and the lowermost portion of the surrounding reinforcement bars away from each other. According to this, by contracting or expanding the spiral portion, the conveyance form and the reinforcement form can be easily formed in the surrounding reinforcement bars.

[0010] The spiral portion may be wound such that its size gradually decreases from the uppermost portion to the lowermost portion. According to this, in the conveyance form, the annular portion of the lower spiral portion is accommodated inside the annular portion of the upper spiral portion, so that the height of the conveyance form can be made lower.

[0011] Alternatively, the surrounding reinforcement bars may be composed of a plurality of annular reinforcement bars connected by a string-like member, and the string-like member extends in the direction of gravity and the annular reinforcement bars are separated from each other to form the reinforcement form. According to this, by lifting the uppermost annular reinforcement bar upward at the site, the plurality of lower annular reinforcement bars are connected by the string-like member due to gravity and the height increases, while in a state where the uppermost annular reinforcement bar is not lifted, a conveyance form in which the upper and lower adjacent annular reinforcement bars are close to each other and the height is reduced is formed.

[0012] The plurality of annular reinforcement bars may be smaller in size as they are lower. According to this, in the conveyance form, the lower annular reinforcement bar can be accommodated inside the upper annular reinforcement bar, so that the height of the conveyance form can be made lower.

[0013] A regulating portion may be provided inside at least the uppermost portion of the surrounding reinforcement bar, contact the outer peripheral surface of the pile head portion, and regulate the horizontal movement of the uppermost portion. According to this, the labor for manufacturing the regulating portion at the site can be eliminated.

[0014] The above-mentioned regulating part may be composed of a plurality of straight reinforcing bars that form a grid pattern in plan view, with the head part of the pile passing through the four side parts on the central side of the grid and the outer peripheral surface of the head part of the pile approaching the central side of each side of the four side parts. According to this, even when there are protrusions on the outer peripheral surface of the head part of the foundation pile, the protrusions can be passed through on the diagonal line of the four side parts. In addition, since a grid is formed by a plurality of straight reinforcing bars, it is easy to manufacture, and the strength of the reinforcing bar hardened body part formed around the head part of the pile can also be improved.

[0015] Moreover, the manufacturing method according to the present invention is a manufacturing method of manufacturing a completed reinforcing bar cage on site using a reinforcing bar cage in which the surrounding bars have spiral parts, and transporting the reinforcing bar cage to the site in the above-mentioned transport form, and applying a load to pull the uppermost part and the lowermost part of the spiral part away from each other at the site, thereby forming the surrounding bars into the above-mentioned reinforcement form.

[0016] In this manufacturing method, longitudinal bars may be attached from the uppermost part to the lowermost part of the surrounding bars in the above-mentioned reinforcement form. Here, in a structure where the completed reinforcing bar cage is in a form without attaching the longitudinal bars, cracking on the surface of the reinforcing bar hardened body part can be suppressed.

[0017] Moreover, the manufacturing method according to the present invention is a manufacturing method of manufacturing a completed reinforcing bar cage on site using a reinforcing bar cage having a plurality of annular bars connected by the above-mentioned string-like members, and transporting the reinforcing bar cage to the site in the above-mentioned transport form, and suspending the other lower annular bars by the above-mentioned string-like members in a state of supporting the annular bar that is the uppermost part among the plurality of annular bars of the surrounding bars at the site, thereby forming the surrounding bars into the above-mentioned reinforcement form, and attaching longitudinal bars from the uppermost part to the lowermost part of the surrounding bars.

Effects of the Invention

[0018] Regarding the reinforcing cage for the pile head of the foundation pile of the present invention, by forming the peripheral bars of this reinforcing cage into the transportation form, it is possible to transport a large number even with a vehicle having a small loading space. Also, by forming the above peripheral bars into the reinforcement form at the site, the effect that the completed reinforcing cage can be manufactured relatively easily and accurately at the site is achieved.

Brief Description of the Drawings

[0019]

Figure 1

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Embodiments for Carrying Out the Invention

[0020] (Embodiment 1) Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In Fig. 1, a completed reinforcing cage A prepared on-site using a reinforcing cage 1 is disposed in the surrounding space S around the pile head 21 of a foundation pile 2 composed of a ready-made pile such as a circular steel pipe buried in the ground. It is shown that a hardened body (not shown) such as concrete or mortar placed in the surrounding space S forms a reinforced rebar hardened body portion of the pile head 21. In the example shown in Fig. 1, the reinforcement form of the reinforcing cage 1 coincides with the above-mentioned completed reinforcing cage A.

[0021] The reinforcing cage 1 has a peripheral reinforcement 10. This peripheral reinforcement 10 has a size that is horizontally spaced from the outer peripheral surface of the pile head 21 of the foundation pile 2 and is located around the outer peripheral surface. As shown in Fig. 2(A), while forming a transportation form that is lowered in the height direction of the pile head 21, as shown in Fig. 2(B), it forms the above-mentioned reinforcement form with an increased height.

[0022] In this embodiment, the peripheral reinforcement 10 has, for example, an annular reinforcement 11 at the uppermost side, an annular reinforcement 11 at the lowermost side, and a spiral portion 12 connecting these annular reinforcements 11, 11.

[0023] Each annular reinforcement 11 is made of a bar processed into an annular shape and is manufactured with a diameter spaced from the peripheral surface of the pile head 21 of the foundation pile 2. The diameter of the annular reinforcement 11 at the uppermost side is made larger than the diameter of the annular reinforcement 11 at the lowermost side.

[0024] Each annular bar 11 is attached with a restricting portion 13 that contacts the outer peripheral surface of the pile head portion 21 and restricts the horizontal movement of the annular bar 11. The restricting portion 13 is composed of, for example, four straight reinforcing bars 13a. These four straight reinforcing bars 13a are located inside each annular bar 11 and both ends thereof are welded to the annular bar 11. Two sets of two straight reinforcing bars 13a that are parallel to each other are positioned at 90-degree different directions from each other, thereby forming a cross shape in plan view. And, the central side four-side portions of the cross shape are located at the central position of the annular bar 11, the pile head portion 21 passes through the inside of these four-side portions, and the outer peripheral surface of the pile head portion 21 is close to each side of the four-side portions.

[0025] The upper end portion of the spiral portion 12 is welded to the annular bar 11 that is the uppermost side portion, and the lower end portion of the spiral portion 12 is welded to the annular bar 11 that is the lowermost side portion. The spiral portion 12 is formed by spirally winding a reinforcing bar such that the size (diameter) gradually decreases from the uppermost side portion to the lowermost side portion, and by pulling the uppermost side portion and the lowermost side portion away from each other, the height of the spiral portion 12 can be increased.

[0026] In a method of manufacturing the completed reinforcing cage A on-site using such a reinforcing cage 1 having the peripheral bars 10 with the spiral portion 12, the reinforcing cage 1 is transported to the site in the above-described transport form, and at the site, a load for pulling the uppermost side portion and the lowermost side portion of the spiral portion 12 away from each other is applied using a machine or manually to form the peripheral bars 10 into the above-described reinforcing form. As the above-described machine, a manual lifter that raises and lowers a lift claw with a rotating handle can be used. The annular bar 11 that is the lowermost side portion is hooked on the leg side of this manual lifter, the annular bar 11 that is the uppermost side portion is hooked on the side of the lift claw, and by raising this lift claw, the spiral portion 12 can be formed into the above-described reinforcing form.

[0027] In this way, in the reinforcing steel cage 1, while the peripheral bars 10 form a reinforced shape that is higher in the height direction of the pile head portion 21, they also form a transport shape in which this height is reduced. Therefore, it is possible to transport a large number of them even with a vehicle having a small loading space. Further, by setting the peripheral bars to the above-described reinforced shape on-site, the completed reinforced steel cage A can be manufactured on-site relatively easily and accurately.

[0028] Next, a method for reinforcing the pile head portion 21 of the foundation pile 2 using the reinforced shape (completed reinforced steel cage A) of the reinforcing steel cage 1 will be described with reference to FIGS. 3 to 7. In the following, the reinforced shape (completed reinforced steel cage A) of the reinforcing steel cage 1 may be simply referred to as the reinforcing steel cage 1.

[0029] As shown in FIGS. 3(A) and 3(B), the foundation pile 2 is buried in the ground. This burying work can be performed by driving or rotary pressing the foundation pile 2 using a heavy machine. Next, a cylindrical peripheral space S is formed around the pile head portion 21 of the foundation pile 2. The formation of the peripheral space S is performed by rotating a boring rotary tool 5 having a boring screw while being supported by a heavy machine around a tubular body that is externally fitted to the pile head portion 21 to excavate the soil around the pile head portion 21. Note that the excavation of the peripheral space S may be performed first, and then the construction of burying the foundation pile 2 from the bottom surface of the peripheral space S may be performed.

[0030] On the outer peripheral surface of the pile head portion 21, for example, four cage support protrusions 21a for locking the four side portions of the cross in the straight bar 13a of the annular bar 11 of the uppermost portion are welded and fixed at 90-degree intervals in the same horizontal plane (in the case of two, at 180 degrees). In the foundation pile 2 used in this embodiment, for example, two casting tips 21b are welded at 180-degree intervals in the same horizontal plane on the outer peripheral surface at a position above the cage support protrusion 21a, and two cage support protrusions 21a overlap and are positioned with respect to the two tips 21b in plan view.

[0031] Next, as shown in FIGS. 4(A) and 4(B), the lifted reinforcing steel cage 1 is gradually lowered, and the pile head portions 21 are passed through the four side portions of the cross-shaped portion of the well of the reinforcing steel cage 1. At this time, the two tips 21b and the four cage support protrusions 21a are positioned on the diagonal lines of the four side portions of the cross-shaped portion of the well in the straight bars 13a of the annular bar 11 at the lowermost side portion, and the annular bar 11 at the lowermost side portion is positioned below the four cage support protrusions 21a.

[0032] Then, as also shown in FIG. 5, the operator manually rotates the reinforcing steel cage 1 by 45 degrees in the horizontal plane, and as also shown in FIG. 6, each central side of the four side portions of the cross-shaped portion of the well of the annular bar 11 at the uppermost side portion is supported by the four cage support protrusions 21a. In terms of design, since the separation height from the bottom surface of the surrounding space S for the cage support protrusions 21a of the embedded foundation pile 2 is set to be a certain distance higher than the height of the reinforcing steel cage 1, when the uppermost annular bar 11 is supported by the four cage support protrusions 21a, the reinforcing steel cage 1 is in a floating state from the bottom surface of the surrounding space S.

[0033] Next, as also shown in FIGS. 7(A) and 7(B), with the reinforcing steel cage 1 floating from the bottom surface of the surrounding space S, a hardened body CC such as concrete or mortar is placed. Thereby, a reinforcing steel bar hardened body portion RC is produced around the pile head portion 21.

[0034] In this way, by placing the hardened body CC with the reinforcing steel cage 1 floating from the bottom surface of the surrounding space S of the pile head portion 21, it is possible to appropriately ensure the covering of the hardened body CC on the lower side portion of the reinforcing steel bar hardened body portion RC produced around the pile head portion 21.

[0035] In the above-described reinforcement method, the four cage support protrusions 21a were welded and fixed to the outer peripheral surface of the pile head 21, but it is not limited to this. The four cage support protrusions 21a may be provided so as to be position-adjustable in the height direction of the foundation pile 2. According to this, even when the foundation pile 2 buried in the ground is stuck up due to the ground hardness, by lowering the height position of the four cage support protrusions 21a, the lower end of the reinforcing cage 1 can be floated from the bottom surface of the surrounding space S by a certain distance.

[0036] Such a position-adjustable cage support protrusion 21a may be provided with a strong magnet that is magnetically adhered to the foundation pile 2 which is a steel pipe pile. In the four cage support protrusions 21a made of this magnet, in order to avoid the mutual 90-degree interval not being maintained during position adjustment, the four cage support protrusions 21a may be connected to each other in an annular shape so as to be integrally position-adjusted. Further, while forming a vertical groove on the outer peripheral surface of the pile head 21, a vertical convex portion guided by the vertical groove is formed on the back surface of the cage support protrusion 21a, and the cage support protrusion 21a may be guided in the height direction of the pile head 21.

[0037] The above four cage support protrusions 21a may not be welded to the foundation pile 2 in advance, but may be fixed to the outer peripheral surface of the foundation pile 2 by on-site welding after checking the situation of the foundation pile 2 buried in the ground.

[0038] Also, as shown in FIGS. 8(A) and 8(B), the reinforcing cage 1 may be suspended from the upper end of the pile head 21 by the four suspension tools 6 hooked to the upper end of the pile head 21, so that the reinforcing cage 1 floats from the bottom surface of the surrounding space S. The hooking of the suspension tool 6 to the upper end of the pile head 21 is performed manually by an operator. Then, in this way, with the reinforcing cage 1 floating from the bottom surface of the surrounding space S, the hardened body CC is placed, and after the placed hardened body CC has hardened to a certain extent, all or part of the suspension tool 6 is recovered.

[0039] The suspension tool for suspending the reinforcing steel bar cage 1 from the upper end of the pile head 21 is not limited to the above structure. For example, hooking parts (hooks, clips, etc.) may be provided at both the upper and lower ends of the wire, the lower hooking part is hooked on the reinforcing steel bar cage 1, and the upper hooking part is hooked on the upper edge of the pile head 21. In such a suspension tool, after the placed hardened body CC has solidified to a certain extent, for example, the wire above the hardened body CC may be cut, the wire inside the hardened body and the lower hooking part may be left, and only the upper hooking part and a part of the wire may be recovered.

[0040] When cutting the upper end of the pile head 21 due to the pile 2 buried in the ground getting stuck high due to the ground hardness, in the suspension tool shown above, the length of the wire (connection part) does not particularly need to be adjustable. On the other hand, when not cutting the upper end of the pile head 21 when the above-mentioned high sticking occurs, it is better to use a suspension tool with an adjustable wire (connection part) length. This length adjustment can be performed using, for example, a commercially available wire stopper that fixes the wire with the screwing pressure of a bolt, or a member such as a wire lock.

[0041] Here, according to the reinforcement method using the above-mentioned reinforcing steel bar cage 1 (completed reinforcing steel bar cage A), the pile head 21 and the reinforcing steel bar hardened body part RC are integrated, and the occurrence of cracks and damage in the reinforcing steel bar hardened body part RC due to the reinforcement effect of the reinforcing steel bar cage 1 can be suppressed.

[0042] The completed reinforcing steel bar cage B shown in FIGS. 9(A) and 9(B) is fabricated on-site by placing the longitudinal bars 14 inside the peripheral part of the reinforcing steel bar cage 1 in the form during reinforcement and connecting these longitudinal bars 14 to the circular bars 11, 11 and the spiral part 12 with wire ties or the like. In this example, four longitudinal bars 14 are arranged at positions inside the circular bars 11, 11 and the spiral part 12 at intervals of, for example, 90 degrees, but it is not limited to such a form.

[0043] Further, in the above example, since the spiral portion 12 is wound such that its size gradually decreases from the uppermost portion to the lowermost portion, in the above-described conveyance form, the annular portion of the lower spiral portion 12 can be accommodated inside the annular portion of the upper spiral portion 12, and the height of the above-described conveyance form can be reduced. However, the present invention is not limited to such a configuration example. Even if the spiral portion 12 is wound with a constant size from the uppermost portion to the lowermost portion, the distance between adjacent spiral portions in the vertical direction becomes narrow, so the height of the above-described conveyance form can be reduced.

[0044] Moreover, when the spiral portion 12 is wound such that its size gradually decreases from the uppermost portion to the lowermost portion, there is no particular problem even in a case where the peripheral wall of the surrounding space S peels off and the bottom side becomes narrow. Also, even if the reinforcing rebar hardened body portion RC has an inverted frustum shape, there is an advantage that the amount of the hardened body CC used can be reduced while exhibiting strength comparable to that of a cylindrical shape. In other words, if the surrounding space S is formed in an inverted frustum concave shape (see the virtual line in FIG. 8(B)), the excavation becomes easier, and if the same amount of the hardened body CC is used, the strength of the reinforcing rebar hardened body portion RC may be improved.

[0045] (Embodiment 2) Hereinafter, other embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 10 shows a completed reinforcing rebar cage C fabricated on-site using the reinforcing rebar cage 1A of the embodiment.

[0046] The peripheral bars 10A of the reinforcing rebar cage 1A are spaced horizontally from the outer peripheral surface of the pile head portion 21 of the foundation pile 2 and have a size that positions them around the outer peripheral surface. And as shown in FIG. 11(A), the peripheral bars 10A form a conveyance form in which the height of the reinforcing rebar cage 1A is reduced, while as shown in FIG. 11(B), they form a reinforcing form in which the height of the reinforcing rebar cage 1A is increased. Further, as shown in FIG. 11(C), the completed reinforcing rebar cage C is fabricated from the reinforcing rebar cage 1A in the reinforcing form.

[0047] The peripheral bars 10A of the reinforcing steel bar cage 1A, for example, include an annular bar 11 at the uppermost side that is separated from each other, an annular bar 11 at the lowermost side, and annular bars 11 in the middle section. The three (or more) annular bars 11 are smaller in size toward the lower side.

[0048] The adjacent annular bars 11 vertically among these three annular bars 11 are connected by a string-shaped member 111 made of a wire, a resin string, or the like. Due to gravity, the three annular bars 11 can approach each other to form the above-described conveyance form with a reduced height. That is, the reinforcing steel bar cage 1A can be conveyed to the site in the above-described conveyance form. On the other hand, at the site, by, for example, hooking the annular bar 11 at the uppermost side on the lift claws of the manual lifter and lifting it, the two lower annular bars 11 are separated vertically by gravity, and the peripheral bars 10A can form the above-described reinforcement form with an increased height.

[0049] The completed reinforcing steel bar cage C is produced at the site by applying the vertical bars 14 to the inner side of the periphery of the reinforcing steel bar cage 1A in the above-described reinforcement form and connecting the vertical bars 14 to the three annular bars 11 with binding wires or the like.

[0050] In the configuration of this Embodiment 2, a restricting portion 13 is also attached to the annular bar 11 in the middle section, but the restricting portion 13 may not be attached. Also, the four vertical bars 14 are arranged, for example, at 90-degree intervals at positions inside the three annular bars 11, but the arrangement is not limited to such a form. Further, in the completed reinforcing steel bar cage C, the string-shaped member 111 may be removed or left in place.

[0051] In the above-described Embodiments 1 and 2, the peripheral bars 10 and 10A have a frustum shape such as an inverted frustum with a smaller size toward the lower side, but are not limited thereto, and the peripheral bars 10 and 10A may have a cylindrical shape such as a cylindrical shape with the same diameter on the upper and lower sides.

[0052] The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiments within the same scope or an equivalent scope of the present invention.

Explanation of Reference Numerals

[0053] 1: Reinforcing steel cage 1A: Reinforcing steel cage 2: Foundation pile 5: Drilling and rotating tool 6: Hoisting tool 10: Peripheral bars 10A: Peripheral bars 11: Circular bars 12: Spiral part 13: Regulation part 13a: Straight reinforcing bar 14: Vertical bars 21: Pile head 21a: Cage support protrusion 21b: Chip 111: String-like member A: Completed reinforcing steel cage B: Completed reinforcing steel cage C: Completed reinforcing steel cage CC: Hardened body RC: Reinforced steel hardened body part S: Peripheral space

Claims

1. A reinforcing steel cage that is disposed within a surrounding space formed around the head portion of a foundation pile embedded in the ground, and forms a reinforcing steel body portion for the head portion of the pile by a hardened body that hardens over time and is cast within the surrounding space, wherein: it has a size that is horizontally spaced from the outer peripheral surface of the head portion of the foundation pile and is located around the outer peripheral surface, and forms a reinforcing shape that becomes higher in the height direction of the head portion, while forming a transport shape in which this height is reduced, and is provided with surrounding bars. A reinforcing steel cage characterized by this.

2. The reinforcing steel cage according to claim 1, wherein the surrounding bars have a spiral portion that increases in height by pulling apart the uppermost side portion and the lowermost side portion of the surrounding bars from each other. A reinforcing steel cage characterized by this.

3. The reinforcing steel cage according to claim 2, wherein the spiral portion is wound such that its size gradually decreases from the uppermost side portion to the lowermost side portion. A reinforcing steel cage characterized by this.

4. The reinforcing steel cage according to claim 1, wherein the surrounding bars are composed of a plurality of annular bars connected by a string-like member, and the string-like member extends in the direction of gravity and the annular bars are spaced apart from each other to form the reinforcing shape. A reinforcing steel cage characterized by this.

5. The reinforcing steel cage according to claim 4, wherein the plurality of annular bars are smaller in size toward the lower side. A reinforcing steel cage characterized by this.

6. In the reinforcing steel cage according to any one of claims 1 to 5, it is provided inside at least the uppermost side portion of the surrounding bars, contacts the outer peripheral surface of the head portion of the pile, and has a restricting portion that restricts the horizontal movement of the uppermost side portion. A reinforcing steel cage characterized by this.

7. The reinforcing steel cage according to claim 6, wherein the restricting portion forms a cross shape in plan view, and the head portion of the pile passes through the inner sides of the four sides on the central side of the cross shape, and the outer peripheral surface of the head portion approaches the central side of each side of the four sides, and is composed of a plurality of straight steel bars. A reinforcing steel cage characterized by this.

8. A manufacturing method for manufacturing a completed reinforcing steel cage on site, using the reinforcing steel cage according to claim 2 or claim 3, wherein the reinforcing steel cage is transported to the site in the transport shape, and at the site, a load is applied in a direction that pulls the uppermost side portion and the lowermost side portion of the spiral portion apart from each other, thereby forming the surrounding bars into the reinforcing shape. A manufacturing method characterized by this.

9. In the manufacturing method according to claim 8, a longitudinal bar is attached from the uppermost part to the lowermost part of the peripheral bars in the reinforced form. A manufacturing method characterized by this.

10. A manufacturing method of manufacturing a completed reinforced steel bar cage on-site using the reinforced steel bar cage according to claim 4 or claim 5, wherein the reinforced steel bar cage is transported to the site in the above-described transportation form, and at the site, with the uppermost annular bar among the plurality of annular bars of the peripheral bars being supported, the other lower annular bars are suspended by the string-like members to form the peripheral bars in the above-described reinforced form, and a longitudinal bar is attached from the uppermost part to the lowermost part of the peripheral bars. A manufacturing method characterized by this.

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