JP2025111342A - Connecting fitting set and connecting method - Google Patents

Abstract

[Problem] To provide a connecting fitting set that enables efficient connection of steel pipes and reinforcing bar cages used in constructing cast-in-place piles without using welding.
[Solution] A connecting fitting set 1 for connecting a steel pipe and a reinforcing bar cage used in constructing cast-in-place piles, comprising a fitting main body 10 attached to the opening edge of the steel pipe, and a rod-shaped joint 50 for connecting the fitting main body 10 to the main reinforcement of the reinforcing bar cage, the rod-shaped joint 50 having a fastening section 52 at one end that allows the fitting main body 10 to be fastened to align with the steel pipe, and an overlapping section 55 at the other end that allows it to be fixed in an overlapping state with the main reinforcement of the reinforcing bar cage, the fitting main body 10 having an insertion section 11 that can be fitted into the opening edge of the steel pipe, an insertion section 13 into which the fastening section 52 of the rod-shaped joint 50 can be inserted, and a fixing section 16 for fixing the steel pipe to the insertion section 11 by applying a pressing force to the steel pipe when fitted into the insertion section 11.
[Selected Figure] Figure 1

Description

The present invention relates to a metal connector set and a connection method, and more specifically to a metal connector set for connecting steel pipes and reinforcing bar cages used in constructing cast-in-place piles, and a connection method for connecting steel pipes and reinforcing bar cages using the metal connector set.

At construction sites, a common method of building structures is to drive piles into the ground to form pile foundations that support the structure, in order to increase the structure's earthquake resistance. One method of building pile foundations is using cast-in-place piles, and one such type of cast-in-place pile is a cast-in-place steel-pipe concrete pile, which uses a steel pipe at the pile head.

FIG. 9 is a side cross-sectional view that schematically shows an example of a conventional cast-in-place steel pipe concrete pile.
The cast-in-place steel pipe concrete pile 80 has a lower reinforced concrete section 82 in which a reinforcing bar cage 81 is arranged, and an upper steel pipe concrete section 84 in which a steel pipe 83 is arranged, and is structured so that it is connected to the columns and foundation beams of the structure via a pile head joint (also called a footing) 85 at the top of the steel pipe concrete section 84.

A joint 86 is constructed below the steel pipe concrete section 84, connecting the steel pipe 83 and the reinforcing bar cage 81. Conventionally, the work of connecting the steel pipe 83 and the reinforcing bar cage 81 to construct the joint 86 has been carried out by on-site welding. The on-site welding work has been carried out, for example, in the following procedure.
First, the reinforcing bar cage 81 is temporarily supported in a casing (not shown) above the pile hole 87, and then the lower part of a steel pipe 83 suspended by a crane or the like is placed over the upper part of the reinforcing bar cage 81 to a predetermined depth.

A connecting rod (flat steel, square steel, etc.) slightly longer than the outer diameter of the steel pipe 83 was then inserted approximately horizontally into the reinforcing bar cage 81 from below the steel pipe 83, and a short rod (short deformed steel bar) was then placed on the outer surface near the bottom end of the steel pipe 83 so that it intersected with the connecting rod and also intersected with the main reinforcement (vertical reinforcement) of the reinforcing bar cage 81. The outer surface near the bottom end of the steel pipe 83 was then welded to the short rod, the intersections between the short rod and the connecting rod, and the intersections between the connecting rod and the main reinforcement of the reinforcing bar cage 81 by on-site welding.

As another connection method, the following Patent Document 1 discloses a method in which a joint rebar is welded to the welded section on the inner surface of a steel pipe near its lower end, and then the upper end of the reinforcing bar cage and the joint rebar protruding downward from the steel pipe are overlapped at the top of the pile hole to form a lap joint between the joint rebar of the steel pipe and the upper end of the reinforcing bar cage, and then the steel pipe and the reinforcing bar cage are erected together to a specified depth into the pile hole.

[Problem to be solved by the invention]
As described above, in the joint portion 86 that connects the steel pipe 83 and the reinforcing bar cage 81, when the steel pipe 83 and the reinforcing bar cage 81 are joined by on-site welding using the connecting rod, the short rod, or the joint reinforcing bar, it is necessary to secure highly skilled welders on-site to ensure construction quality, and there is also the problem that the welding work takes time, resulting in poor work efficiency.

In addition, the "Highway Bridge Specifications and Commentary" (November 2017, Japan Road Association) stipulates that direct welding to the main reinforcement bars, which are the main components of the reinforcing bar cage, should not be used, as welding may result in defects such as a reduction in the cross-sectional area of the reinforcing bars. In recent years, there has been a demand for a method of connecting the steel pipes and reinforcing bar cages used in the construction of cast-in-place piles without welding.

JP 2015-121040 A

Means to solve the problem and their effects

The present invention was developed in consideration of the above-mentioned problems, and aims to provide a connecting hardware set and connecting method that allows the efficient connection of steel pipes and reinforcing bar cages used in constructing cast-in-place piles without the use of welding.

In order to achieve the above object, the connecting fitting set (1) according to the present invention comprises:
A connecting fitting set for connecting a steel pipe and a reinforcing bar cage used to construct a cast-in-place pile,
a metal fitting body attached to the opening edge portion of the steel pipe;
a rod-shaped joint for connecting the metal fitting body and the main reinforcement of the reinforcing bar cage,
The rod-shaped joint is
a fastening portion on one end of the metal fitting body that can be fastened in accordance with the position of the steel pipe;
An overlapping portion is provided on the other end side that can be fixed in a state overlapping with the main reinforcement of the reinforcing bar cage,
The overlapping portion and the main reinforcement of the reinforcing bar cage can be fixed with a reinforcing bar fixing metal fitting,
The metal fitting body is
a fitting portion that can be fitted into the opening edge portion of the steel pipe;
an insertion portion into which the fastening portion of the rod-shaped joint can be inserted;
The device is characterized by having a fixing portion for fixing the steel pipe to the fitting portion while applying a pressing force to the steel pipe when fitted into the fitting portion.

With the above-mentioned connecting fitting set (1), by using the fitting body having the fitting portion, the insertion portion, and the fixing portion, and the rod-shaped joint having the fastening portion and the overlapping portion, the work of connecting the steel pipe and the reinforcing bar cage can be performed efficiently without using welding.

The connecting fitting set (2) according to the present invention is the above connecting fitting set (1),
the metal fitting body includes a pair of plate-like members arranged opposite to each other and a tubular member that constitutes the insertion portion,
the fitting portions are configured by notches formed at opposing positions of the pair of plate-like members,
the tubular member is disposed between the pair of plate-like members in parallel with the depth direction of the notch portion,
the fixing portion includes a nut fixed to each outer surface of the pair of plate-like members and a set screw that can be threaded onto the nut,
The nut is fixed in a direction that allows the setscrew to be threaded in a direction perpendicular to the depth direction of the notch.

With the above-mentioned connecting fitting set (2), the fitting body can be easily attached to the fastening portion of the rod-shaped joint, and the fitting portion, which is composed of the notches formed at opposing positions on the pair of plate-shaped members, can be easily fitted into the opening edge of the steel pipe, thereby improving the efficiency of the connecting work. Furthermore, the nut and set screw that constitute the fixing portion allow the fitting body to be firmly and reliably fixed to the opening edge of the steel pipe.

The connecting fitting set (3) according to the present invention is the above connecting fitting set (2),
The notch is characterized in that a locking portion is formed in the notch portion so as to be able to lock onto an annular protrusion formed on the inner surface of the steel pipe.

With the above-mentioned connecting fitting set (3), the locking portion formed in the notch can be locked onto the annular protrusion formed on the inner surface of the steel pipe, allowing the fitting body to be more firmly and securely fixed to the opening edge of the steel pipe, thereby improving the effectiveness of preventing the connected reinforcing bar cage from shifting out of position.

Furthermore, the connecting fitting set (4) of the present invention is characterized in that, in the connecting fitting set (2) or (3) described above, the tubular members are arranged on both sides of the cutout portion.

According to the above connecting fitting set (4), the tubular members are arranged on both sides of the cutout portion, so that the fitting body can be used when connecting the reinforcing bar cage at the bottom of the steel pipe, and when connecting the reinforcing bar cage at the top of the steel pipe.
That is, the metal fitting main body can be attached to the edge of the lower opening of the steel pipe, the fastening portion of the rod-shaped joint can be inserted into the tubular member and fastened, and the overlapping portion of the rod-shaped joint can be fixed in a state where it overlaps with the main reinforcement bars of the reinforcing bar cage. Alternatively, the metal fitting main body can be attached to the edge of the upper opening of the steel pipe, the fastening portion of the rod-shaped joint can be inserted into the tubular member and fastened, and the overlapping portion of the rod-shaped joint can be fixed in a state where it overlaps with the main reinforcement bars of the reinforcing bar cage.

The connecting fitting set (5) according to the present invention is the above connecting fitting set (1),
the metal fitting body includes a plate-like member having a substantially L-shaped notch and a tubular member that constitutes the insertion portion,
a tip end of a short side of the notch portion of the plate-like member and one side surface of the tubular member are fixed together in a state in which a long side of the notch portion and one side surface of the tubular member face each other,
the fitting portion is formed by the notch portion and one side surface of the tubular member,
the fixing portion includes nuts fixed to both side surfaces of the tubular member in a direction parallel to an extension direction of the short sides of the notched portion, and set screws that can be threaded onto the nuts,
The nut is fixed in a direction that allows the setscrew to be threaded in a direction perpendicular to the extension direction of the long side of the notch.

With the above-mentioned connecting fitting set (5), the fitting body can be easily attached to the fastening portion of the rod-shaped joint, and the fitting portion formed by the approximately L-shaped cutout and one side of the tubular member can be easily fitted into the opening edge of the steel pipe, improving the efficiency of the connecting work. Furthermore, the nut and set screw that constitute the fixing portion allow the fitting body to be firmly and securely fixed to the opening edge of the steel pipe. Furthermore, by using the plate-shaped member with the approximately L-shaped cutout for the fitting body, the weight and cost of the fitting body can be reduced.

The connecting fitting set (6) according to the present invention is the above connecting fitting set (5),
The metal fitting body is
The tubular member further includes a reinforcing member fixed to the other side opposite to the one side,
The nut is fixed to the tubular member and the reinforcing member.

With the above-mentioned connecting fitting set (6), the nuts fixed to both sides of the tubular member are firmly attached to the tubular member and the reinforcing member, thereby increasing the mounting strength of the nuts and enabling the steel pipe fitted into the fitting portion to be firmly fixed with the setscrew threaded into the nuts.

The connecting fitting set (7) according to the present invention is the above connecting fitting set (5) or (6),
The notch is characterized in that a locking portion is formed in the notch portion so as to be able to lock onto an annular protrusion formed on the inner surface of the steel pipe.

With the above-mentioned connecting hardware set (7), the locking portion formed in the notch can be locked onto the annular protrusion formed on the inner surface of the steel pipe, allowing the hardware body to be more firmly and securely fixed to the opening edge of the steel pipe, thereby improving the effectiveness of preventing the connected reinforcing bar cage from shifting out of position.

The connecting fitting set (8) according to the present invention is any one of the connecting fitting sets (1) to (7),
The rod joint is
The steel pipe is made of a steel bar bent according to the difference between the outer diameter or inner diameter and the cage diameter of the reinforcing bar cage,
The fastening portion is
One end of the steel bar is configured with a threaded portion,
A pair of nuts for positioning and fastening the metal fitting body can be screwed onto the threaded portion.

According to the above connecting fitting set (8), the rod-shaped joint is made of a steel bar that has been bent in accordance with the difference between the outer diameter or inner diameter of the steel pipe and the cage diameter of the reinforcing bar cage, so that the fastening portion of the rod-shaped joint can be positioned close to the steel pipe and the overlapping portion can be positioned close to the main reinforcement of the reinforcing bar cage.
Furthermore, since the fastening portion is composed of the threaded portion and the set of nuts is configured to be able to be screwed onto the threaded portion, the fastening position of the metal fitting body inserted into the threaded portion can be easily adjusted with the set of nuts.

The connecting fitting set (9) according to the present invention is the above connecting fitting set (8),
A slip prevention bar is fixed to the other end of the steel bar that becomes the overlapping portion to prevent misalignment of the connection position with the main bar of the reinforcing bar cage,
The overlapping portion and the anti-slip bars are configured so that they can be fixed to the main bars of the reinforcing bar cage with the reinforcing bar fixing metal fittings.

With the above-mentioned connecting fitting set (9), the anti-slip bar is fixed to the other end of the steel bar that forms the overlapping portion, so the overlapping portion and the main reinforcement of the reinforcing bar cage can be firmly fixed together with the reinforcing bar fixing fitting.

The connecting fitting set (10) according to the present invention is any one of the connecting fitting sets (1) to (7),
The rod joint is
The steel pipe is made of a steel bar bent according to the difference between the outer diameter or inner diameter and the cage diameter of the reinforcing bar cage,
The fastening portion is
The steel bar is configured by a screw member attached to one end side thereof,
A pair of nuts for positioning and fastening the metal fitting body can be screwed onto the screw members.

According to the above connecting fitting set (10), the rod-shaped joint is made of a steel bar that has been bent in accordance with the difference between the outer diameter or inner diameter of the steel pipe and the cage diameter of the reinforcing bar cage, so that the fastening portion of the rod-shaped joint can be positioned close to the steel pipe and the overlapping portion can be positioned close to the main reinforcement of the reinforcing bar cage.
Furthermore, since the fastening portion is formed by the screw member and the set of nuts is configured to be able to be screwed onto the screw member, the fastening position of the metal fitting main body inserted into the screw member attached to one end side of the steel bar can be easily adjusted with the set of nuts.

The connecting fitting set (11) according to the present invention is the above connecting fitting set (10),
The steel bar is made of a deformed steel bar,
The overlapping portion at the other end of the steel bar is configured to be fixable to the main reinforcement of the reinforcing bar cage with the reinforcing bar fixing metal fittings.

With the above-mentioned connecting fitting set (11), the steel bars are made of deformed steel bars, so the overlapping portion at the other end of the steel bars and the main reinforcement of the reinforcing bar cage can be firmly fixed together with the reinforcing bar fixing fittings.

A connecting method (12) according to the present invention is a method for connecting a steel pipe and a reinforcing bar cage using any of the above connecting metal fitting sets (1) to (11),
After temporarily receiving the reinforcing bar cage in the casing at the top of the pile hole, the overlapping portion of the rod-shaped joint is overlapped on the main reinforcement of the reinforcing bar cage, and the rod-shaped joint is attached to the main reinforcement with a reinforcing bar fixing metal fitting;
a step of inserting the insertion portion of the metal fitting body into the fastening portion of the rod-shaped joint attached to the main reinforcement and temporarily fastening the metal fitting body to the fastening portion with the fitting portion facing upward;
A process of covering the lower part of the steel pipe with the reinforcing bar cage up to a predetermined fixing position;
a step of positioning and fastening the metal fitting body to the fastening portion with the fitting portion of the metal fitting body fitted into the lower opening edge portion of the steel pipe;
and fixing the steel pipe to the fitting portion while applying a pressing force to the steel pipe with the fixing portion of the metal fitting body.

According to the above-mentioned connection method (1), by using the connection fitting set, which includes the fitting body having the fitting ...

The connecting method (2) according to the present invention is a method for connecting a steel pipe and a reinforcing bar cage using the connecting metal fitting set (1),
The method includes a step of temporarily receiving the steel pipe in a casing at the top of the pile hole, and then erecting the reinforcing bar cage into the steel pipe,
The erection process is
a step of overlapping the overlapping portion of the rod-shaped joint with the main reinforcement of the reinforcing bar cage and attaching the rod-shaped joint to the main reinforcement with a reinforcing bar fixing metal fitting;
a step of attaching the rod-shaped joint to the main reinforcement, and then erecting the reinforcing bar cage into the steel pipe, and when the fastening portion of the rod-shaped joint is positioned at the upper opening edge of the steel pipe, inserting the insertion portion into the fastening portion of the rod-shaped joint with the fitting portion of the metal fitting main body facing downward, and positioning and fastening the metal fitting main body to the fastening portion with the fitting portion fitted into the upper opening edge of the steel pipe;
and fixing the steel pipe to the fitting portion while applying a pressing force to the steel pipe with the fixing portion of the metal fitting body.

According to the above-mentioned connection method (2), by using the connection fitting set, which includes the fitting body having the fitting fitting portion, the insertion portion, and the fixing portion, and the rod-shaped joint having the fastening portion and the overlapping portion, the work of connecting the upper part of the steel pipe and the upper part of the reinforcing bar cage can be performed efficiently without using welding.

1 is a front view showing a state before assembly of a connecting fitting set according to embodiment (1) of the present invention. FIG. FIG. 2 is a right side view of FIG. 1. 10 is a side view illustrating an example of a work procedure for connecting a steel pipe and a reinforcing bar cage used to construct a cast-in-place pile using a connecting fitting set according to embodiment (1). FIG. 10A and 10B are diagrams showing the general configuration of the metal fitting body constituting the connecting metal fitting set according to embodiment (2), where (a) is a front view, (b) is a right side view, (c) is a left side view, and (d) is a plan view. FIG. 11 is a front view showing the state before assembly of the connecting fitting set according to the embodiment (3). FIG. 6 is a right side view of FIG. 5 . 10 is a side view illustrating an example of a work procedure for connecting a steel pipe and a reinforcing bar cage used to construct a cast-in-place pile using a connecting fitting set according to embodiment (3). FIG. 10A to 10C are diagrams showing the schematic configuration of the metal fitting body constituting the connecting metal fitting set according to embodiment (4), where (a) is a front view, (b) is a right side view, and (c) is a plan view. FIG. 1 is a side cross-sectional view schematically showing an example of a conventional cast-in-place steel pipe concrete pile.

Embodiments of the connecting fitting set and connecting method according to the present invention will be described below with reference to the drawings. The embodiments described below are preferred examples of the present invention, and therefore include various technically desirable limitations. However, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

Fig. 1 is a front view showing a state before assembly of a connecting fitting set 1 according to a first embodiment of the present invention. Fig. 2 is a right side view of Fig. 1.
The connecting fitting set 1 is for connecting a steel pipe 83 used in constructing a cast-in-place pile to a reinforcing bar cage 81 (see Figure 3), and includes a fitting body 10 attached to the lower opening edge of the steel pipe 83, and a rod-shaped joint 50 for connecting the fitting body 10 to the main reinforcement 81a of the reinforcing bar cage 81 (see Figure 3).

The rod-shaped joint 50 has a fastening portion 52 at one end (upper end) that allows the metal fitting body 10 to be fastened in alignment with the steel pipe 83, and an overlapping portion 55 at the other end (lower end) that can be fixed in an overlapping state with the main reinforcement 81a of the reinforcing bar cage 81; the overlapping portion 55 and the main reinforcement 81a of the reinforcing bar cage 81 can be fixed with a reinforcing bar fixing metal fitting 70 (see Figure 3).

The rod-shaped joint 50 is composed of round steel (steel bar) 51 that has been bent into a shape (also called a reducer shape) in which both ends are offset parallel to each other according to the difference between the outer diameter of the steel pipe 83 and the cage diameter of the reinforcing bar cage 81.
The fastening portion 52 of the rod-shaped joint 50 is configured to include a threaded portion 53 formed by threading one end of the round steel 51, and is configured so that a set of nuts consisting of a lower nut 54a and an upper nut 54b for positioning and fastening the metal fitting main body 10 can be screwed onto the threaded portion 53.

At the overlapping portion 55 of the rod-shaped joint 50, a slippage prevention bar 56 is fixed to the round steel bar 51 to prevent misalignment of the connection position with the main reinforcement 81a of the reinforcing bar cage 81. The slippage prevention bar 56 is made, for example, of a deformed steel bar with approximately the same diameter as the round steel bar 51. The round steel bar 51 and slippage prevention bar 56 at the overlapping portion 55 are configured to be fixed to the main reinforcement 81a of the reinforcing bar cage 81 with reinforcing bar fixing hardware 70.

The metal fitting body 10 includes an insertion portion 11 that can be inserted into the lower opening edge of the steel pipe 83, an insertion portion 13 into which the threaded portion 53 that constitutes the fastening portion 52 of the rod-shaped joint 50 can be inserted, and a fixing portion 16 that fixes the steel pipe 83 to the insertion portion 11 by applying a pressing force to the steel pipe 83 when it is inserted into the insertion portion 11.

More specifically, the metal fitting body 10 includes a pair of plate-like members 12 arranged opposite each other and a tubular member 14 that constitutes the insertion portion 13, and the fitting portion 11 is composed of a roughly U-shaped cutout portion 12a formed at an opposing position of the pair of plate-like members 12.
A tubular member 14 and a reinforcing plate 15 are provided between the pair of plate-like members 12. The tubular member 14 is provided parallel to the depth direction of the notch 12a and positioned outside the steel pipe 83 when fitted into the fitting portion 11. The reinforcing plate 15 is provided parallel to the depth direction of the notch 12a and positioned opposite the tubular member 14 across the notch 12a. The pair of plate-like members 12 are made of, for example, steel plate, and the thickness of the steel plate is appropriately set depending on specifications such as required strength. The tubular member 14 is made of, for example, a small-diameter steel pipe with a length of approximately 100 mm to 150 mm, and the reinforcing plate 15 is made of, for example, a rectangular flat steel having the same width as the diameter of the tubular member 14. The tubular member 14 and the reinforcing plate 15 are fixed to the pair of plate-like members 12 by, for example, welding.

The notched portions 12a that make up the fitting portion 11 are formed with locking portions 12b that can lock onto annular protrusions (also called ribs) 83a (see Figure 3) formed on the inner surface of the steel pipe 83. The locking portions 12b are formed at intervals similar to the spacing between the protrusions 83a of the steel pipe 83. The shape of the locking portions 12b is triangular when viewed from the front, but is not limited to this shape and may be formed into other shapes that can lock onto the protrusions 83a of the steel pipe 83. The notched portions 12a and locking portions 12b are formed, for example, by laser cutting the steel plate that makes up the plate-like member 12.

The fixing portion 16 includes nuts 17 fixed to the outer surfaces of the pair of plate-like members 12 , and set screws 18 that can be threaded onto these nuts 17 .
The nuts 17 are fixed in a direction that allows the set screws 18 to be threaded in a direction perpendicular to the depth direction of the cutout portions 12 a. There is no particular limit to the number of nuts 17 attached, but it is preferable to provide nuts in two or more locations on the outer surfaces of each of the pair of plate-like members 12 in order to increase the fixing force with the steel pipe 83.

The set screw 18 is, for example, a hexagon socket set screw (also known as a hollow set screw). Set screws 18 are available with a variety of tip shapes (concave point, flat point, pointed point, rod point, double point, etc.), but it is preferable to use a set screw with a pointed tip to increase the fixing force with the steel pipe 83.

Next, with reference to Figure 3, an example of a work procedure for connecting a steel pipe 83 and a reinforcing bar cage 81 used to construct a cast-in-place pile using the connecting fitting set 1 according to embodiment (1) will be described.
Figure 3 shows an example of a method (cover-type connection method) for connecting a reinforcing bar cage 81 and a steel pipe 83 in a state where the lower part of a steel pipe 83 is placed over the upper part of the reinforcing bar cage 81 that constitutes the reinforced concrete portion at the bottom of a cast-in-place steel pipe concrete pile.

FIG. 3(a) shows a state in which a reinforcing bar cage 81 is erected in a casing 88 placed in a pile hole, and the upper part of the reinforcing bar cage 81 is supported at the opening of the casing 88 using a receiving jig (not shown).
The reinforcing bar cage 81 is composed of a number of main reinforcements 81a arranged in the central axis direction on the circumference, a number of hoop reinforcements 81b that are approximately perpendicular to the main reinforcements 81a, and a number of reinforcing rings 81c that contact the main reinforcements 81a from the inside of the reinforcing bar cage 81 and are fixed at their intersections with the main reinforcements 81a.

After the reinforcing bar cage 81 is temporarily placed in the opening of the casing 88 above the pile hole, the overlapping portion 55 at the lower end of the rod-shaped joint 50 is overlapped with the main reinforcement 81a of the reinforcing bar cage 81, as shown in Figure 3(b), and the rod-shaped joint 50 is attached to the main reinforcement 81a using a reinforcing bar fixing bracket 70. At this time, the overlapping portion 55 of the rod-shaped joint 50 is positioned on the circumference of the reinforcing bar cage 81, which is formed by multiple main reinforcement bars 81a, overlapping the side of the main reinforcement bars 81a. Furthermore, the overlapping position of the overlapping portion 55 of the rod-shaped joint 50 and the main reinforcement bars 81a of the reinforcing bar cage 81 is adjusted so that the position of the threaded portion 53 at the upper end of the rod-shaped joint 50 is near the position of the lower end opening of the steel pipe 83 (the specified fixing position) when the steel pipe 83 is placed over the reinforcing bar cage 81 in a subsequent process. Additionally, multiple rod-shaped joints 50 are arranged at predetermined intervals around the circumference of a reinforcing bar cage 81 formed from numerous main reinforcements 81a. The predetermined intervals are designed appropriately taking into account the size (diameter, perimeter length) and weight of the reinforcing bar cage 81, etc.

The reinforcing bar fixing hardware 70 is composed of a U-bolt 71, a plate 72 with a through hole formed therein that can be inserted into the threaded tip portion of the U-bolt 71, and a nut 73 that can be screwed onto the threaded tip portion of the U-bolt 71.
To install the reinforcing bar fastening fitting 70, the main reinforcement 81a and the overlapping portion 55 are overlapped as described above, and then the U-bolt 71 is fitted between the main reinforcement 81a and the overlapping portion 55. Then, the plate 72 and nut 73 are attached to the U-bolt 71 and the nut 73 is tightened. At this stage, it is not necessary to tighten the nut 73 firmly; it is sufficient to tighten the nut 73 just enough so that the main reinforcement 81a and the overlapping portion 55 do not come loose.

After temporarily fastening the overlapping portion 55 to the main reinforcement 81a, the lower nut 54a is screwed onto the threaded portion 53 on one end of the rod-shaped joint 50. The lower nut 54a may be pre-threaded onto the threaded portion 53. Then, the tubular member 14 of the metal fitting body 10 is inserted into the threaded portion 53 of the rod-shaped joint 50 with the notched portion 12a facing upward, and the metal fitting body 10 is inserted into the threaded portion 53, so that the metal fitting body 10 is supported by the lower nut 54a screwed onto the threaded portion 53, as shown in Figure 3(c).

Next, as shown in Figures 3(c) and (d), a steel pipe 83 suspended by a crane or the like is placed over the main reinforcement 81a of the reinforcing bar cage 81 up to the specified fixed position (joint length) marked on the main reinforcement 81a. At this time, as shown in Figure 3(d), the lower end opening of the steel pipe 83 is somewhat fitted into the notched portion 12a of the metal fitting body 10 supported by the rod-shaped joint 50.

Then, while adjusting the height of the lower nut 54a threaded onto the threaded portion 53 of the rod-shaped joint 50, the metal fitting body 10 is positioned so that the locking portion 12b formed in the cutout portion 12a of the metal fitting body 10 is locked onto the protrusion 83a formed on the inside of the steel pipe 83, as shown in Figures 3(d) and (e).

After the position adjustment of the metal fitting body 10 using the lower nut 54a is completed, the upper nut 54b is screwed onto the threaded portion 53 of the rod-shaped joint 50, and the metal fitting body 10 is fastened (fixed) to the threaded portion 53 using this pair of upper and lower nuts 54a, 54b, as shown in Figures 3(e) and 3(f).
Furthermore, the setscrew 18 threaded onto the nut 17 constituting the fixing portion 16 of the metal fitting body 10 is threaded toward the outer circumferential surface of the steel pipe 83, with the tip of the setscrew 18 firmly pressing against the outer circumferential surface of the steel pipe 83, thereby fixing the metal fitting body 10 and the steel pipe 83. The nut 73 of the reinforcing bar fixing metal fitting 70, which temporarily fastens the main reinforcement 81a to the overlapping portion 55, is also retightened, thereby fixing the main reinforcement 81a to the rod-shaped joint 50. The reinforcing bar fixing metal fitting 70, the pair of nuts 54a, 54b, the setscrew 18, etc. can be installed using an electric tool such as an impact wrench.

After all of the connecting fitting sets 1 arranged around the circumference of the reinforcing bar cage 81 have been used to connect the main reinforcement bars 81a of the reinforcing bar cage 81 to the steel pipes 83, the connected steel pipes 83 and reinforcing bar cage 81 are lifted up, the support jig (not shown) for the reinforcing bar cage 81 arranged on top of the casing 88 is removed, and the cage is then erected into the pile hole.

The connecting fitting set 1 according to the above-described embodiment (1) uses a fitting body 10 having an inserting portion 21, an inserting portion 13, and a fixing portion 16, and a rod-shaped joint 50 having a fastening portion 52 and an overlapping portion 55, allowing the work of connecting a steel pipe 83 and a reinforcing bar cage 81 to be carried out efficiently without the use of welding.

In addition, the tubular member 14 of the metal fitting body 10 can be easily attached to the fastening portion 52 (threaded portion 53) of the rod-shaped joint 50, and the fitting portion 11, which is composed of the notches 12a formed at opposing positions on the pair of plate-shaped members 12, can be easily fitted into the lower opening edge of the steel pipe 83, improving the efficiency of the connection work. Furthermore, the nut 17 and set screw 18 that make up the fixing portion 16 allow the metal fitting body 10 to be firmly and securely fixed to the lower opening edge of the steel pipe 83.

The locking portion 12b is formed in the notch 12a of the metal fitting body 10, allowing the locking portion 12b to be engaged with the annular protrusion 83a formed on the inner surface of the steel pipe 83. This allows the metal fitting body 10 to be more firmly and securely fixed to the lower opening edge of the steel pipe 83, thereby improving the prevention of misalignment of the connected reinforcing bar cage 81.

Furthermore, since the rod-shaped joint 50 is made of round steel 51 that has been bent according to the difference between the outer diameter of the steel pipe 83 and the cage diameter of the reinforcing bar cage 81, the fastening portion 52 of the rod-shaped joint 50 can be positioned close to the steel pipe 83, and the overlapping portion 55 can be positioned close to the main reinforcement 81a of the reinforcing bar cage 81.
Furthermore, the fastening portion 52 is composed of a threaded portion 53, and a pair of upper and lower nuts 54a, 54b are configured to be able to be screwed onto the threaded portion 53, so that the fastening position of the metal fitting body 10 inserted into the threaded portion 53 can be easily adjusted with the pair of upper and lower nuts 54a, 54b.
In addition, since a slip prevention bar 56 is fixed to the other end of the round steel 51, which forms the overlapping portion 55 of the rod-shaped joint 50, the overlapping portion 55 and the main bar 81a of the reinforcing bar cage 81 can be firmly fixed with a reinforcing bar fixing bracket 70.

Furthermore, according to the method of connecting a steel pipe 83 and a reinforcing bar cage 81 using the connecting fitting set 1 according to embodiment (1) described with reference to Figure 3, by using the connecting fitting set 1 which includes a fitting body 10 having an inserting portion 11, an inserting portion 13, and a fixing portion 16, and a rod-shaped joint 50 having a fastening portion 52 and an overlapping portion 55, the work of connecting the lower part of the steel pipe 83 and the upper part of the reinforcing bar cage 81 can be performed efficiently without using welding.

Note that while the cast-in-place pile shown in Figure 3 was constructed using a steel pipe 83 with a protrusion 83a formed on the inside, the connecting fitting set 1 can also be used to connect a steel pipe 83 without a protrusion 83a formed on the inside to a reinforcing bar cage 81.

Figure 4 shows the schematic configuration of the fitting body 20 that constitutes the connecting fitting set 1A according to embodiment (2), with (a) being a front view, (b) being a right side view, (c) being a left side view, and (d) being a plan view. The rod-shaped joint that constitutes the connecting fitting set 1A according to embodiment (2) is configured in the same way as the rod-shaped joint 50 of the connecting fitting set 1 according to embodiment (1) (see Figures 1 and 2), so it is designated by the same reference numeral and its description will be omitted here.

The metal fitting body 20 constituting the connecting metal fitting set 1A according to the embodiment (2) is attached to the lower opening edge of the steel pipe 83.
The metal fitting body 20 is configured to include an insertion portion 21 that can be inserted into the lower opening edge of the steel pipe 83, an insertion portion 23 into which the fastening portion 52 of the rod-shaped joint 50 can be inserted, and a fixing portion 26 for fixing the steel pipe 83 to the insertion portion 21 by applying a pressing force to the steel pipe 83 when it is inserted into the insertion portion 21.

More specifically, the metal fitting main body 20 includes a plate-like member 22 having a substantially L-shaped cutout 22a, and a tubular member 24 that constitutes the insertion portion 23, and the tip of the short side of the cutout 22a of the plate-like member 22 is fixed to one side of the tubular member 24 with the long side of the cutout 22a of the plate-like member 22 facing one side of the tubular member 24. The cutout 22a and one side of the tubular member 24 form a substantially U-shaped fitting portion 21.
The metal fitting body 20 also includes a reinforcing member 25 fixed to the other side of the tubular member 24 opposite to the side to which the plate-like member 22 is fixed. The plate-like member 22 is made of a steel plate, and the thickness of the steel plate is set appropriately according to specifications such as the required strength. The tubular member 24 is made of a thin steel pipe approximately 200 mm to 250 mm in length, and the reinforcing member 25 is made of a strip-shaped flat steel whose width is approximately the same as the diameter of the tubular member 24 and whose length is shorter than that of the tubular member 24.

The notched portion 22a constituting the fitting portion 21 has locking portions 22b formed therein that can lock onto the annular protrusions 83a (see Figure 3) formed on the inner surface of the steel pipe 83. The locking portions 22b are formed at intervals similar to the spacing between the protrusions 83a of the steel pipe 83. The shape of the locking portions 22b is a sharp triangle, but is not limited to this shape and may be formed into other shapes that can lock onto the protrusions 83a of the steel pipe 83. The notched portion 22a and the locking portions 22b are formed, for example, by laser cutting the steel plate that constitutes the plate-like member 22.

The fixing portion 26 is composed of nuts 27 fixed to both side surfaces of the tubular member 24 and both side surfaces of the reinforcing member 25 in a direction parallel to the extension direction of the short side of the cutout portion 22a, and set screws 28 that can be screwed into these nuts 27.
The nut 27 is fixed in a direction that allows the set screw 28 to be threaded in a direction perpendicular to the extension direction of the long side of the notched portion 22 a. There is no particular limit to the number of nuts 27 attached, but it is preferable to provide nuts at two or more locations on both side surfaces of the tubular member 24 in order to increase the fixing force with the steel pipe 83.

The set screw 28 is, for example, a hexagon socket set screw. It is preferable to use a set screw 28 with a pointed tip to increase the fixing force to the steel pipe 83.

The procedure for connecting the steel pipe 83 and reinforcing bar cage 81 used to construct a cast-in-place pile using the connecting fitting set 1A according to embodiment (2) is substantially the same as the procedure shown in Figure 3, and therefore will not be described here.

The connecting fitting set 1A according to the above-described embodiment (2) uses a fitting body 20 having an inserting portion 21, an inserting portion 23, and a fixing portion 26, and a rod-shaped joint 50 (see Figures 1 and 2) having a fastening portion 52 and an overlapping portion 55, so that the work of connecting the steel pipe 83 and the reinforcing bar cage 81 can be performed efficiently without welding, just as with the connecting fitting set 1 according to the above-described embodiment (1).

The tubular member 24 of the metal fitting body 20 can be easily attached to the fastening portion 52 (threaded portion 53) of the rod-shaped joint 50, and the fitting portion 21 formed by the approximately L-shaped cutout portion 22a and one side of the tubular member 24 can be easily fitted into the lower opening edge of the steel pipe 83, improving the efficiency of the connecting work. Furthermore, the nut 27 and set screw 28 that make up the fixing portion 26 allow the metal fitting body 20 to be firmly and securely fixed to the lower opening edge of the steel pipe 83. Furthermore, by using a plate-like member 22 having a substantially L-shaped cutout portion 22a as the metal fitting body 20, the metal fitting body 20 can be made lighter and less expensive than the connecting metal fitting set 1 according to embodiment (1).

The locking portion 22b is formed in the notch 22a of the metal fitting body 20, allowing the locking portion 22b to be engaged with the annular protrusion 83a formed on the inner surface of the steel pipe 83. This allows the metal fitting body 20 to be more firmly and securely fixed to the lower opening edge of the steel pipe 83, thereby improving the prevention of misalignment of the connected reinforcing bar cage 81.

Furthermore, according to the method of connecting a steel pipe 83 and a reinforcing bar cage 81 using the connecting fitting set 1A according to embodiment (2), by using the connecting fitting set 1A which includes the fitting body 20 having the fitting portion 21, the insertion portion 23, and the fixing portion 26, and the rod-shaped joint 50 having the fastening portion 52 and the overlapping portion 55, the work of connecting the lower part of the steel pipe 83 and the upper part of the reinforcing bar cage 81 can be performed efficiently without welding, just as when using the connecting fitting set 1 according to embodiment (1) described above.

Fig. 5 is a front view showing a state before assembly of a connecting fitting set 1B according to a third embodiment of the present invention. Fig. 6 is a right side view of Fig. 5.
Cast-in-place concrete steel pipe piles include those in which the lower part of a steel pipe 83 is partially placed over the upper part of a reinforcing cage 81 as shown in Figure 3, i.e., those having a steel pipe concrete section 84 of a non-reinforced concrete structure in which the reinforcing cage 81 is not inserted into the steel pipe 83, as well as those having a steel pipe concrete section 84 of a reinforced concrete structure in which the reinforcing cage 81 is inserted into the steel pipe 83.

The connecting fitting set 1B of embodiment (3) is intended to connect a steel pipe 83 and a reinforcing bar cage 81 used to construct a cast-in-place steel pipe concrete pile 80 having a steel pipe concrete section 84 of the steel pipe reinforced concrete structure.
The connecting fitting set 1B includes a fitting body 30 that is attached to the upper opening edge of the steel pipe 83, and a rod-shaped joint 60 for connecting the fitting body 30 to the main reinforcement 81a at the upper part of the reinforcing bar cage 81 inserted into the steel pipe 83.

The rod-shaped joint 60 has a fastening portion 63 at one end (upper end) that allows the metal fitting body 30 to be fastened in alignment with the steel pipe 83, and an overlapping portion 66 at the other end (lower end) that can be fixed in an overlapping state with the main reinforcement 81a of the reinforcing bar cage 81. The overlapping portion 66 and the main reinforcement 81a of the reinforcing bar cage 81 can be fixed with a reinforcing bar fixing metal fitting 70 (see Figure 7).

The rod joint 60 is configured to include a deformed steel bar 61 that has been bent into a shape (also called a reducer shape) in which both ends are offset parallel to each other in accordance with the difference between the inner diameter of the steel pipe 83 and the cage diameter of the reinforcing bar cage 81. One end (upper end) of the deformed steel bar 61 is formed with a threaded portion 61a for threading a connecting nut 62, and the other end (lower end) forms an overlapping portion 66.
The fastening portion 63 includes a threaded rod 64 attached to the threaded portion 61a on one end side of the deformed steel bar 61 with a connecting nut 62, and is configured so that a set of nuts consisting of a lower nut 65a and an upper nut 65b for positioning and fastening the metal fitting main body 30 can be screwed onto the threaded rod 64.

The metal fitting body 30 includes an insertion portion 31 that can be fitted into the upper opening edge of the steel pipe 83, an insertion portion 33 into which the threaded rod 64 that constitutes the fastening portion 63 of the rod-shaped joint 60 can be inserted, and a fixing portion 36 that fixes the steel pipe 83 to the insertion portion 31 by applying a pressing force to the steel pipe 83 when it is fitted into the insertion portion 31.

More specifically, the metal fitting body 30 includes a pair of plate-like members 32 arranged opposite each other and a tubular member 34 that constitutes the insertion portion 33, and the fitting portion 31 is composed of a cutout portion 32a that is approximately inverted U-shaped and formed at an opposing position between the pair of plate-like members 32.
A tubular member 34 and a reinforcing plate 35 are provided between the pair of plate-like members 32. The tubular member 34 is disposed parallel to the depth direction of the cutout portion 32a and at a position that allows it to be positioned inside the steel pipe 83. The reinforcing plate 35 is disposed parallel to the depth direction of the cutout portion 32a and at a position that faces the tubular member 34 across the cutout portion 32a. The pair of plate-like members 32 are made of, for example, steel plate, and the thickness of the steel plate is appropriately set depending on specifications such as required strength. The tubular member 34 is made of, for example, a small-diameter steel pipe with a length of approximately 100 mm to 150 mm, and the reinforcing plate 35 is made of a rectangular flat steel having a width equal to the diameter of the tubular member 34. The tubular member 34 and the reinforcing plate 35 are fixed to the pair of plate-like members 32 by, for example, welding.

The notch 32a that constitutes the fitting portion 31 has locking portions 32b formed therein that can engage with annular protrusions 83a (see Figure 7) formed on the inner surface of the upper opening of the steel pipe 83. The locking portions 32b are formed at intervals similar to the spacing between the protrusions 83a of the steel pipe 83. The shape of the locking portions 32b is a sharp triangle, but is not limited to this shape and may be formed into other shapes that can engage with the protrusions 83a of the steel pipe 83. The notch 32a and locking portions 32b are formed, for example, by laser cutting the steel plate that constitutes the plate-shaped member 32.

The fixing portion 36 includes nuts 37 fixed to the outer surfaces of the pair of plate-like members 32 , and set screws 38 that can be threaded onto the nuts 37 .
The nuts 37 are fixed in a direction that allows the set screws 38 to be threaded in a direction perpendicular to the depth direction of the cutout portions 32 a. There is no particular limit to the number of nuts 37 attached, but it is preferable to provide nuts at two or more locations on the outer surfaces of each of the pair of plate-like members 32 in order to increase the fixing force with the steel pipe 83.

The setscrew 38 is, for example, a hexagon socket setscrew. It is preferable to use a setscrew 38 with a pointed tip.

Next, with reference to Figure 7, an example of a work procedure for connecting a steel pipe 83 and a reinforcing bar cage 81 used to construct a cast-in-place pile using a connecting fitting set 1B according to embodiment (3) will be described.
Figure 7 illustrates a case where a reinforcing bar cage 81 is inserted into a steel pipe 83 that constitutes the upper steel pipe concrete portion of a cast-in-place steel pipe concrete pile, and the upper part of the reinforcing bar cage 81 is connected to the upper opening edge of the steel pipe 83 (through-type connection method).

Figure 7(a) shows the state midway through the process of erecting a steel pipe 83 into a casing 88 placed in a pile hole, with the top of the steel pipe 83 temporarily supported at the opening of the casing 88 using a receiving jig (not shown), and then erecting a reinforcing bar cage 81 into the steel pipe 83.

As shown in Figure 7(a), the reinforcing bar cage 81 is inserted into the steel pipe 83 until the upper part of the reinforcing bar cage 81 remains above the steel pipe 83, and the reinforcing bar cage 81 is then suspended. Next, as shown in Figure 7(b), the overlapping portion 66 of the rod-shaped joint 60 is overlapped with the main reinforcement 81a at the top of the reinforcing bar cage 81, and the rod-shaped joint 60 is attached to the main reinforcement 81a with a reinforcing bar fixing bracket 70. At this time, the overlapping portion 66 of the rod-shaped joint 60 is arranged overlapping to the side of the main reinforcement 81a so that it is located on the circumference formed by the multiple main reinforcement bars 81a.

The overlap position between the overlapping portion 66 of the rod-shaped joint 60 and the main reinforcement 81a of the reinforcing bar cage 81 is adjusted so that when the reinforcing bar cage 81 is further inserted into the steel pipe 83 in a subsequent process and the threaded rod 64 of the rod-shaped joint 60 is positioned at the edge of the upper opening of the steel pipe 83, a predetermined length of the main reinforcement 81a remains above the steel pipe 83. Furthermore, multiple rod-shaped joints 60 are arranged at predetermined intervals around the circumference of the reinforcing bar cage 81, which is formed by a large number of main reinforcement bars 81a. The predetermined intervals are designed appropriately taking into account the size (diameter, outer perimeter) and weight of the reinforcing bar cage 81, etc.

The reinforcing bar fixing hardware 70 can be installed in the same manner as the connecting hardware set 1 according to embodiment (1) described above, but in this embodiment, the main reinforcement 81a and the overlapping portion 66 are firmly fixed together with the reinforcing bar fixing hardware 70 at this stage.

After fixing the overlapping portion 66 to the main reinforcement 81a with the rebar fixing bracket 70, a lower nut 65a is threaded onto the threaded rod 64 at one end of the rod-shaped joint 60, and the tubular member 34 of the bracket body 30 is inserted into the threaded rod 64 of the rod-shaped joint 60 with the notch 32a facing downward. The bracket body 30 is then inserted onto the threaded rod 64, and the bracket body 30 is supported by the lower nut 65a threaded onto the threaded rod 64, as shown in Figure 7(c).

Next, as shown in Figures 7(c) and (d), the reinforcing bar cage 81, suspended by a crane or the like, is further inserted into the steel pipe 83, so that the upper opening edge of the steel pipe 83 is fitted into the notch 32a of the metal fitting body 30, which is inserted into the threaded rod 64 of the rod-shaped joint 60.

Then, while adjusting the height of the lower nut 65a threaded onto the threaded rod 64 of the rod-shaped joint 60, the metal fitting body 30 is positioned so that the locking portion 32b formed in the cutout portion 32a of the metal fitting body 30 is locked onto the protrusion 83a formed on the inside of the steel pipe 83, as shown in Figures 7(e) and (f).

After the position adjustment of the metal fitting body 30 using the lower nut 65a is completed, the upper nut 65b is screwed onto the threaded rod 64 of the rod-shaped joint 60, and the metal fitting body 30 is fastened (fixed) to the threaded rod 64 using this pair of upper and lower nuts 65a, 65b, as shown in Figures 7(e) and 7(f).
Furthermore, the set screw 38 threaded onto the nut 37 constituting the fixing portion 36 of the metal fitting body 30 is screwed toward the outer peripheral surface of the steel pipe 83, and the tip of the set screw 38 is brought into a state where it is strongly pressed against the outer peripheral surface of the steel pipe 83, thereby fixing the metal fitting body 30 and the steel pipe 83 together.

After all of the connecting fitting sets 1B arranged around the circumference of the reinforcing bar cage 81 have been used to connect the main reinforcement bars 81a of the reinforcing bar cage 81 to the steel pipes 83, the connected steel pipes 83 and reinforcing bar cage 81 are lifted up, the support jig (not shown) for the steel pipes 83 arranged at the top of the casing is removed, and the pile is then erected into the pile hole.

The connecting fitting set 1B according to the above-described embodiment (3) uses a fitting body 30 having an inserting portion 31, an inserting portion 33, and a fixing portion 36, and a rod-shaped joint 60 having a fastening portion 63 and an overlapping portion 66, so that the work of connecting the steel pipe 83 and the reinforcing bar cage 81 that constitute the steel pipe concrete portion of a steel pipe reinforced concrete structure can be performed efficiently without welding.

In addition, the tubular member 34 of the metal fitting body 30 can be easily attached to the fastening portion 63 (threaded rod 64) of the rod-shaped joint 60, and the fitting portion 31, which is composed of the notches 32a formed at opposing positions on the pair of plate-shaped members 32, can be easily fitted into the upper opening edge of the steel pipe 83, improving the efficiency of the connection work. Furthermore, the nut 37 and set screw 38 that make up the fixing portion 36 allow the metal fitting body 30 to be firmly and securely fixed to the upper opening edge of the steel pipe 83.

The locking portion 32b is formed in the notch 32a of the metal fitting body 30, allowing the locking portion 32b to be engaged with the annular protrusion 83a formed on the inner surface of the steel pipe 83. This allows the metal fitting body 30 to be more firmly and securely fixed to the upper opening edge of the steel pipe 83, thereby improving the prevention of misalignment of the connected reinforcing bar cage 81.

Furthermore, since the rod-shaped joint 60 is composed of a deformed steel bar 61 that has been bent according to the difference between the inner diameter of the steel pipe 83 and the cage diameter of the reinforcing bar cage 81, the fastening portion 63 of the rod-shaped joint 60 can be positioned inside the steel pipe 83, and the overlapping portion 66 can be positioned close to the main reinforcement 81a of the reinforcing bar cage 81.
Furthermore, the fastening portion 63 is formed of a threaded rod 64 attached to one end of the deformed steel bar 61 with a connecting nut 62, and a pair of upper and lower nuts 65a, 65b are configured to be able to be screwed onto the threaded rod 64, so that the fastening position of the metal fitting main body 30 inserted into the threaded rod 64 can be easily adjusted with the pair of upper and lower nuts 65a, 65b.
Furthermore, since the overlapping portion 66 of the rod-shaped joint 60 is made of the deformed steel bar 61, the overlapping portion 66 and the main reinforcement 81a of the reinforcing bar cage 81 can be firmly fixed together with the reinforcing bar fixing metal fittings 70.

Furthermore, according to the method of connecting a steel pipe 83 and a reinforcing bar cage 81 using the connecting fitting set 1B according to embodiment (3) described with reference to Figure 7, by using the connecting fitting set 1B, which includes a fitting body 30 having an inserting portion 31, an inserting portion 33, and a fixing portion 36, and a rod-shaped joint 60 having a fastening portion 63 and an overlapping portion 66, the work of connecting the upper part of the steel pipe 83 that constitutes the steel pipe concrete portion of a steel pipe reinforced concrete structure to the reinforcing bar cage 81 can be performed efficiently without welding.

In addition, in the connecting fitting set 1B according to the above-described embodiment (3), it is also possible to use the rod-shaped joint 50 (see Figures 1 and 2) instead of the rod-shaped joint 60, and in the connecting fitting sets 1 and 1A according to the above-described embodiments (1) and (2), it is also possible to use the rod-shaped joint 60 (see Figures 5 and 6) instead of the rod-shaped joint 50.

8A and 8B are diagrams showing the schematic configuration of the metal fitting body 40 constituting the connecting metal fitting set 1C according to embodiment (4), where (a) is a front view and (b) is a right side view. Note that components having the same functions as those of the metal fitting body 10 of the connecting metal fitting set 1 according to embodiment (1) shown in Figures 1 and 2 are given the same reference numerals, and their explanations will be omitted.
Furthermore, the rod-shaped joint that constitutes the connecting fitting set 1C according to embodiment (4) can be the rod-shaped joint 50 of the connecting fitting set 1 according to embodiment (1), or the rod-shaped joint 60 of the connecting fitting set 1B according to embodiment (3), so a description of this will be omitted here.

The connecting hardware set 1 according to the above-mentioned embodiment (1) had the function of attaching the hardware body 10 to the lower opening edge of the steel pipe 83 that constitutes the steel pipe concrete portion of the steel pipe unreinforced concrete structure, thereby connecting the steel pipe 83 to the reinforcing cage 81. The connecting hardware set 1B according to the embodiment (3) had the function of attaching the hardware body 30 to the upper opening edge of the steel pipe 83 that constitutes the steel pipe concrete portion of the steel pipe reinforced concrete structure, thereby connecting the steel pipe 83 to the reinforcing cage 81.
The connecting fitting set 1C of embodiment (4) combines the functions of both the connecting fitting set 1 of embodiment (1) and the connecting fitting set 1B of embodiment (3).

The metal fitting body 40 includes a pair of plate-like members 42 arranged opposite each other and two tubular members 44, 45 that form the insertion portion 43, and the fitting portion 41 is composed of an approximately U-shaped cutout portion 42a formed at an opposing position between the pair of plate-like members 42.
Two tubular members 44 and 45 are disposed between the pair of plate-like members 42 in parallel with the depth direction of the notched portion 42a and at positions facing each other across the notched portion 42a.
The plate-like member 42 is made of a steel plate, and the thickness of the steel plate is set appropriately according to specifications such as the required strength. The two tubular members 44, 45 are each made of a small-diameter steel pipe with a length of approximately 100 mm to 150 mm. The two tubular members 44, 45 are fixed to the pair of plate-like members 42 by, for example, welding.
The notched portion 42 a is formed with a locking portion 42 b that can be locked onto an annular protrusion 83 a formed on the inner surface of the steel pipe 83 .

The fixing portion 46 includes nuts 47 fixed to the outer surfaces of the pair of plate-like members 42 , and set screws 48 that can be threaded onto the nuts 47 .
The nuts 47 are fixed in a direction that allows the set screws 48 to be threaded in a direction perpendicular to the depth direction of the cutout portions 42 a. There is no particular limit to the number of nuts 47 attached, but it is preferable to provide nuts in two or more locations on the outer surfaces of each of the pair of plate-like members 42 in order to increase the fixing force with the steel pipe 83.

The set screw 48 is, for example, a hexagon socket set screw. It is preferable to use a set screw 48 with a pointed tip to increase the fixing force to the steel pipe 83.

In the metal fitting body 40 constituting the connecting metal fitting set 1C according to embodiment (4), tubular members 44, 45 are disposed on both sides of the notched portion 42a of the pair of plate-like members 42.
Therefore, when connecting the steel pipe 83 and the reinforcing bar cage 81 by attaching the fitting body 40 to the lower opening edge of the steel pipe 83, as in the case of the connecting fitting set 1 of embodiment (1), the connecting work can be performed using the same procedure as the work procedure described using Figure 3.
That is, the metal fitting body 40 can be used with the notched portion 42a facing upward, and the threaded portion 53 (threaded rod 64) of the fastening portion 52 (63) of the rod-shaped joint 50 (60) can be inserted into one of the tubular members 44 located on the outside of the steel pipe 83.

Furthermore, when the steel pipe 83 and the reinforcing bar cage 81 are connected by attaching the fitting body 40 to the upper opening edge of the steel pipe 83, as in the case of the connecting fitting set 1B according to embodiment (3), the connecting work can be carried out using the same procedure as that described using Figure 7.
That is, the metal fitting body 40 can be used with the notched portion 42a facing downward, and the threaded rod 64 (threaded portion 53) of the fastening portion 63 (52) of the rod-shaped joint 60 (50) can be inserted into the other tubular member 45 located inside the steel pipe 83.

According to the connecting fitting set 1C relating to the above-mentioned embodiment (4), the tubular members 44, 45 are arranged on both sides of the cutout portion 42a of the fitting body 40, so that the fitting body 40 can be used when connecting to the reinforcing bar cage 81 at the bottom of the steel pipe 83, and when connecting to the reinforcing bar cage 81 at the top of the steel pipe 83. This means that one type of fitting body 40 can be used for two types of construction methods, thereby increasing versatility.
The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the above-described embodiment (1), the pair of plate-like members 12 and the tubular member 14 that make up the metal fitting body 10 are formed as separate members, but they do not necessarily have to be formed as separate members, and the metal fitting body may be formed from a single member in which the fitting portion 11 and the insertion portion 13 are formed.

1, 1A, 1B, 1C Connecting fitting set 10, 20, 30, 40 Fitting body 11 Fitting portion 12 Pair of plate-shaped members 12a Cutout portion 12b Locking portion 13 Insertion portion 14 Tubular member 15 Reinforcing plate 16 Fixing portion 17 Nut 18 Set screw 21 Fitting portion 22 Plate-shaped member 22a Cutout portion 22b Locking portion 23 Insertion portion 24 Tubular member 25 Reinforcing member 26 Fixing portion 27 Nut 28 Set screw 31 Fitting portion 32 Pair of plate-shaped members 32a Cutout portion 32b Locking portion 33 Insertion portion 34 Tubular member 35 Reinforcing plate 36 Fixing portion 37 Nut 38 Set screw 41 Fitting portion 42 Pair of plate-shaped members 42a Cutout portion 42b Locking portion 43 Insertion portions 44, 45 Tubular member 46 Fixing portion 47: Nut 48: Set screw 50: Rod joint 51: Round steel 52: Fastening portion 53: Threaded portion (threaded portion)
54a Lower nut, 54b Upper nut (one set of nuts)
55 overlapping portion 56 slip prevention bar 60 rod-shaped joint 61 deformed steel bar (steel bar)
61a Threaded portion 62 Connecting nut 63 Fastening portion 64 Threaded rod (screw member)
65a Lower nut, 65b Upper nut (one set of nuts)
66 overlapping portion 70 reinforcing bar fixing metal fittings 71 U-bolt 72 plate 73 nut 80 cast-in-place steel pipe concrete pile 81 reinforcing bar cage 81a main reinforcement 81b hoop reinforcement 81c reinforcing ring 82 reinforced concrete portion 83 steel pipe 83a protrusion portion 84 steel pipe concrete portion 85 pile head joint portion (footing)
86 Joint portion 87 Pile hole 88 Casing

Claims (13)

A connecting fitting set for connecting a steel pipe and a reinforcing bar cage used to construct a cast-in-place pile,
a metal fitting body attached to the opening edge portion of the steel pipe;
a rod-shaped joint for connecting the metal fitting body and the main reinforcement of the reinforcing bar cage,
The rod-shaped joint is
a fastening portion on one end thereof that enables the metal fitting body to be fastened in alignment with the position of the steel pipe;
An overlapping portion is provided on the other end side that can be fixed in a state overlapping with the main reinforcement of the reinforcing bar cage,
The overlapping portion and the main reinforcement of the reinforcing bar cage can be fixed with a reinforcing bar fixing metal fitting,
The metal fitting body is
a fitting portion that can be fitted into the opening edge portion of the steel pipe;
an insertion portion into which the fastening portion of the rod-shaped joint can be inserted;
a fixing portion for fixing the steel pipe to the fitting portion by applying a pressing force to the steel pipe when fitted into the fitting portion. the metal fitting body includes a pair of plate-like members arranged opposite to each other and a tubular member that constitutes the insertion portion,
the fitting portions are configured by notches formed at opposing positions of the pair of plate-like members,
the tubular member is disposed between the pair of plate-like members in parallel with the depth direction of the notch portion,
the fixing portion includes a nut fixed to each outer surface of the pair of plate-like members and a set screw that can be threaded onto the nut,
2. The connecting fitting set according to claim 1, wherein the nut is fixed in an orientation that allows the setscrew to be threaded in a direction perpendicular to the depth direction of the notch. The connecting fitting set according to claim 2, characterized in that the notch has a locking portion formed therein that can be engaged with an annular protrusion formed on the inner surface of the steel pipe. The connecting fitting set according to claim 2, characterized in that the tubular members are arranged on both sides of the notch. the metal fitting body includes a plate-like member having a substantially L-shaped notch and a tubular member that constitutes the insertion portion,
a tip end of a short side of the notch portion of the plate-like member and one side surface of the tubular member are fixed together in a state in which a long side of the notch portion and one side surface of the tubular member face each other,
the fitting portion is formed by the notch portion and one side surface of the tubular member,
the fixing portion includes nuts fixed to both side surfaces of the tubular member in a direction parallel to an extension direction of the short sides of the notched portion, and set screws that can be threaded onto the nuts,
2. The connecting fitting set according to claim 1, wherein the nut is fixed in an orientation that allows the setscrew to be threaded in a direction perpendicular to the extension direction of the long side of the notch. The metal fitting body is
The tubular member further includes a reinforcing member fixed to the other side opposite to the one side,
6. The connecting fitting set according to claim 5, wherein the nut is fixed to the tubular member and the reinforcing member. The connecting fitting set according to claim 5, characterized in that the notch has a locking portion formed therein that can be engaged with an annular protrusion formed on the inner surface of the steel pipe. The rod joint is
The steel pipe is made of a steel bar bent according to the difference between the outer diameter or inner diameter and the cage diameter of the reinforcing bar cage,
The fastening portion is
One end of the steel bar is configured with a threaded portion,
The connecting fitting set according to any one of claims 1 to 7, characterized in that a set of nuts for positioning and fastening the fitting body can be screwed onto the threaded portion. A slip prevention bar is fixed to the other end of the steel bar that becomes the overlapping portion to prevent misalignment of the connection position with the main bar of the reinforcing bar cage,
9. The connecting fitting set according to claim 8, wherein the overlapping portion and the anti-slip bars are configured to be fixed to the main bars of the reinforcing bar cage with the reinforcing bar fixing fittings. The rod joint is
The steel pipe is configured to include a steel bar bent according to the difference between the outer diameter or inner diameter of the steel pipe and the cage diameter of the reinforcing bar cage,
The fastening portion is
The steel bar is configured by a screw member attached to one end side thereof,
The connecting fitting set according to any one of claims 1 to 7, characterized in that a set of nuts for positioning and fastening the fitting body can be screwed onto the screw members. The steel bar is made of a deformed steel bar,
The connecting fitting set according to claim 10, characterized in that the overlapping portion on the other end side of the steel bar is configured to be fixable to the main reinforcement of the reinforcing bar cage with the reinforcing bar fixing fitting. A method for connecting a steel pipe and a reinforcing bar cage using the connecting metal fitting set according to claim 1,
After temporarily receiving the reinforcing bar cage in the casing at the top of the pile hole, the overlapping portion of the rod-shaped joint is overlapped on the main reinforcement of the reinforcing bar cage, and the rod-shaped joint is attached to the main reinforcement with a reinforcing bar fixing metal fitting;
a step of inserting the insertion portion of the metal fitting body into the fastening portion of the rod-shaped joint attached to the main reinforcement and temporarily fastening the metal fitting body to the fastening portion with the fitting portion facing upward;
A process of covering the lower part of the steel pipe with the reinforcing bar cage up to a predetermined fixing position;
a step of positioning and fastening the metal fitting body to the fastening portion with the fitting portion of the metal fitting body fitted into the lower opening edge portion of the steel pipe;
and fixing the steel pipe to the fitting portion while applying a pressing force to the steel pipe with the fixing portion of the metal fitting body. A method for connecting a steel pipe and a reinforcing bar cage using the connecting metal fitting set according to claim 1,
The method includes a step of temporarily receiving the steel pipe in a casing at the top of the pile hole, and then erecting the reinforcing bar cage into the steel pipe,
The erection process is
a step of overlapping the overlapping portion of the rod-shaped joint with the main reinforcement of the reinforcing bar cage and attaching the rod-shaped joint to the main reinforcement with a reinforcing bar fixing metal fitting;
a step of attaching the rod-shaped joint to the main reinforcement, and then erecting the reinforcing bar cage into the steel pipe, and when the fastening portion of the rod-shaped joint is positioned at the upper opening edge of the steel pipe, inserting the insertion portion into the fastening portion of the rod-shaped joint with the fitting portion of the metal fitting main body facing downward, and positioning and fastening the metal fitting main body to the fastening portion with the fitting portion fitted into the upper opening edge of the steel pipe;
and fixing the steel pipe to the fitting portion while applying a pressing force to the steel pipe with the fixing portion of the metal fitting body.