JP2004183220A - Pile head joint structure, pile head joint hard ware and its construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pile head joint structure excellent in construction in a site, a joint metal fixture and a construction method capable of having high reliability on tensile force or compressive force acting on an anchor reinforcement and reducing the number of components. <P>SOLUTION: The metal fixture 1 consisting of circular members 1a and 1b is mounted so as to hold a joint section from both sides to the joint section of a pile steel pipe 10. A plurality of U-shaped fitting grooves 3 are formed at a regular interval in the inner circumferential surface of the metal fixture 1, the lower end bending section of the anchor reinforcement 5 is mounted in a state to fit it to the fitting groove 3 to mount the U-shaped anchor reinforcement 5 in the form held between the outer circumferential surface of the butt section and the inner circumferential surface of the metal fixture 1. Furthermore, projection sections 11a and 11b and recess sections 4a and 4b fitted to each other are formed in the outer circumferential surface of the butt section and the inner circumferential surface section of the metal fixture 1, the butt structure can be utilized for positioning the metal fixture 1 or the like, and besides it can be contributed to the transfer of stress in a state to complete the butt joint section. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pile head joint in which a pile head of a pile steel pipe constituting a foundation pile such as a steel pipe pile or a steel pipe concrete pile and a concrete structure such as a footing or a slab located above the pile head are connected via anchoring bars. The present invention relates to a structure, a pile head joint fitting, and a construction method of a pile head joint part.
[0002]
[Prior art]
As one of joining structures between a pile head of a steel pipe pile or a steel pipe concrete pile used as a foundation of a structure and a concrete structure such as a footing, there is a structure in which these are joined via a reinforcing bar or the like.
[0003]
More specifically, as shown in FIG. 7, a reinforcing rod cage system in which a reinforcing rod cage 22 is inserted into a steel pipe 21 at the pile head, and a reinforcing rod 24 is welded to the outer periphery of the steel pipe 21 at the pile head as shown in FIG. There are a beard type, a coupler type in which a screw rebar is fixed with a coupler as a connection device with a screw hole (see Patent Document 1).
[0004]
However, the reinforcing bar cage method has a narrow arrangement space for the reinforcing bars, and the reinforcing bars are densely arranged, resulting in poor workability. Further, since the reinforcing steel is arranged inside the steel pipe, there is a problem that the sectional efficiency with respect to bending is low.
[0005]
Further, the beard bar method has problems in workability and welding quality when welding a reinforcing bar to a steel pipe. The coupler system described in Patent Document 1 also has problems in the workability, weldability, and the like of the coupler and the steel pipe, as in the case of the beard bar system, and also raises the cost due to a dedicated coupler and the like.
[0006]
In order to solve such a problem, the present applicant attaches a connection fitting having an arc-shaped part below to the outer periphery of the pile head of the foundation pile, and as a pile head anchoring stud corresponding to the arc-shaped part of this connection fitting. A pile head joint structure in which a joint reinforcing bar formed in a U-shape is fixed has been developed (see Patent Document 2).
[0007]
In addition, Patent Literature 3 discloses, as a mounting structure for a pile head anchor bar, a structure in which a pile head anchor bar is attached to a band-like connector fixed to an outer peripheral surface of a pile head by welding or a nut. The band-shaped connector is, for example, a ring obtained by dividing a ring into two parts, and fixed by tightening with a high-strength bolt or the like.
[0008]
[Patent Document 1]
Japanese Patent Publication No. 03-054736 [Patent Document 2]
JP 2002-115256 A [Patent Document 3]
JP 2002-146781 A [Patent Document 4]
JP 2002-256552 A
[Problems to be solved by the invention]
As mentioned above, the pile head joint structure of conventional steel pipe piles or steel pipe concrete piles has the problem of tight rebar arrangement due to the arrangement space of anchoring bars, workability, section efficiency against bending, and the cost of using a special coupler. There are various problems to be solved, such as problems of weldability, workability, quality, cost due to increase of steel weight, workability, and fixing effect.
[0010]
Further, the one described in Patent Document 2 using a U-shaped fixing streak has a high reliability with respect to a tensile force acting on the fixing streak, but has a problem of workability due to an increase in the number of parts, and has a problem with other compressive forces. There is a problem of proof stress and difficulty in adjusting the position of the anchoring muscle.
[0011]
Further, in the case of Patent Document 3, it is difficult to perform on-site welding when an anchor bar is welded to a band-like connector, and if it is welded in advance, it becomes inconvenient for transportation and the like. In addition, there is a problem in the resistance to the tensile force and the compressive force acting on the anchor bar including the case where the anchor bar is attached with a nut or the like.
[0012]
The present invention is intended to solve the above-mentioned problems in the prior art, and has high reliability with respect to tensile force and compressive force acting on anchoring muscles, and can reduce the number of parts. It is an object of the present invention to provide a pile head joint structure, a joint fitting, and a construction method which are excellent in quality.
[0013]
[Means for Solving the Problems]
The invention according to claim 1 of the present application joins a pile head of a pile steel pipe constituting a foundation pile and an upper concrete structure via a plurality of anchoring bars extending in the pile axis direction and anchored in the concrete. In the pile head joint structure, a plurality of U-shaped anchoring bars having a bent portion at a lower end are used as the anchoring bars, and the periphery of a ring-shaped mounting bracket attached to an outer peripheral portion or an upper end portion of the pile head is used. The lower end bent portion of the U-shaped fixing stud is fitted and attached to a fitting groove or a fitting hole formed at intervals in the direction.
[0014]
The upper concrete structure referred to here is usually a footing, a slab, a foundation beam, or the like, but is not particularly limited as long as it is a concrete structure to which a pile head is connected, such as when columns are directly connected.
[0015]
As the anchoring bars, for example, those obtained by bending a central portion of a reinforcing bar into a U-shape or the like can be used, but those obtained by bending a wire-shaped bar into a U-shape, and other pile heads and an upper concrete structure A material other than a reinforcing bar may be used as long as the stress can be transmitted between them.
[0016]
In the above configuration, basically, the fixing line is attached by fitting the bent portion of the U-shaped fixing line into the fitting groove or the fitting hole, and the tensile force or the form at the fitting portion Can withstand the compressive force, and the pile steel pipe (steel pipe in case of steel pipe pile, steel pipe filled with concrete in case of steel pipe concrete pile) and the upper concrete structure are joined without welding The problem of workability and quality in the case of welding can be eliminated.
[0017]
Also, there is no need for special hardware such as couplers, and, except for the mounting bracket and the plurality of U-shaped fixing streaks, use the minimum parts for joining these as necessary, or use grout. Inexpensive bonding is possible by reducing the number of components.
[0018]
According to a second aspect of the present invention, in the pile head joint structure according to the first aspect, the ring-shaped mounting member is formed of a plurality of members divided in a circumferential direction, and is attached to an outer peripheral surface of the pile head. It is characterized by the following.
[0019]
When attaching the mounting bracket to the outer peripheral surface of the pile head, the ring-shaped mounting bracket should be divided into two or more than three parts so that it can be attached relatively easily to the outer peripheral surface of the pile head. Can be. Note that, depending on the form, it may not always be necessary to closely contact.
[0020]
In addition, the smaller the number of divisions, the more the number of parts can be reduced, and the number of connection points between the divided members also decreases.
[0021]
According to a third aspect of the present invention, in the pile head joint structure according to the second aspect, the member divided into a plurality in the circumferential direction is formed by binding between connecting portions formed at both ends of the member. It is characterized by being attached to the outer peripheral surface of the head.
[0022]
For example, a connecting portion for bolt connection is provided at an end of a member constituting a ring-shaped mounting bracket, and a tension is introduced in a circumferential direction of the mounting bracket by tightening using a high-strength bolt or the like. It can be tightly fixed to the outer peripheral surface of the pile head using the tension.
[0023]
According to a fourth aspect of the present invention, in the pile head joint structure according to the second or third aspect, the inner and outer peripheral surfaces of the member divided in the circumferential direction and the outer peripheral surface of the pile head are provided with irregularities to be fitted to each other. It is characterized by having.
[0024]
If the contact surface between the inner peripheral surface of the mounting bracket and the pile head is flat, it may be time-consuming to attach the mounting bracket, or it may be displaced even after the mounting, but irregularities that fit together will be formed. By doing so, these irregularities can be used for positioning, and can be used for temporary fixing or temporary support at the time of attachment. Further, after the attachment, a stress transmitting effect in the uneven portion can be obtained.
[0025]
These irregularities may be obtained by, for example, shaving a concave portion on the inner peripheral surface of the member constituting the mounting bracket or the pile head, forming a concave portion in advance at the time of forming the mounting bracket or the pile steel pipe, or forming a steel material on the pile head. Can be formed by winding (for example, fixing by welding or the like) in a ring shape.
[0026]
According to a fifth aspect of the present invention, in the pile head joint structure according to the first, second, third, or fourth aspect, the fitting groove is formed on an inner peripheral surface of the ring-shaped mounting bracket, and the U-shape is provided. Wherein the anchoring stud is sandwiched between the outer peripheral surface of the pile head and the inner peripheral surface of the ring-shaped mounting bracket.
[0027]
When the mounting bracket is mounted on the outer peripheral surface of the pile head, the fitting groove is formed on the inner peripheral surface side of the mounting bracket, and the lower end bent portion of the U-shaped fixing streak is accommodated in the fitting groove. By attaching the mounting bracket to the pile head, it is possible to prevent the U-shaped fixing streaks from coming out of the mounting bracket, and to resist not only the tensile force from the concrete structure side but also the compressive force.
[0028]
The invention according to claim 6 is the pile head joint structure according to claim 1, wherein the ring-shaped mounting bracket is welded to an outer peripheral surface or an upper end of the pile head.
[0029]
If a ring-shaped mounting bracket is welded, a stable pile head can be installed without complicating the on-site work by attaching a U-shaped fixing streak with a limited number of separate parts to this mounting bracket. A joint structure can be obtained.
[0030]
If the ring-shaped mounting bracket is welded to the pile steel pipe by factory welding, on-site welding is not required, and the U-shaped anchoring streak can be attached on-site without welding. It will be easier.
[0031]
The invention according to claim 7 is the pile head joint structure according to claim 1, 2, 3, 4, or 6, wherein the U-shaped fixing streak is attached to the ring-shaped mounting bracket and the ring-shaped mounting bracket. And a cover plate sandwiched therebetween.
[0032]
For example, in the case where the fitting groove is provided on the outer peripheral surface of the mounting bracket, the U-shaped fixing streak cannot be stably held while being fitted in the fitting groove. By providing a cover plate on the metal fitting, a U-shaped fixing streak is sandwiched between the mounting metal and the cover plate to prevent the metal fitting from coming off, and to resist a tensile force and a compressive force.
[0033]
In the invention according to claim 1, when the U-shaped fixing streak is fitted not in the fitting groove but in the fitting hole provided in the mounting bracket, two rising portions at both ends of the U-shaped fixing streak are provided. Into the two fitting holes from below, or if the fixing streaks have deformation followability, insert one end of the fixing streaks into one end of the U-shaped fitting hole and pull out from the other end It is necessary.
[0034]
In the former case, it is possible to resist the pull-out force from the concrete structure, but it cannot resist the compressive force as it is, and therefore, like the cover plate on the outer peripheral surface side, a mounting bracket having a U-shaped fixing streak inserted therein. If a cover plate is attached to the lower surface of the cover plate, it is possible to prevent the fixing streaks from coming off when a compressive force acts on the cover plate and to resist the compressive force.
[0035]
The pile head joint fitting according to claim 8 of the present application is a joint fitting applicable to the pile head joint structure according to claims 1 to 7, and is an outer peripheral portion or an upper end of a pile head of a pile steel pipe constituting a foundation pile. A ring-shaped mounting bracket attached to the portion, and a plurality of U-shaped fixing streaks arranged at intervals in the circumferential direction of the mounting bracket, the lower end bent portion of the U-shaped fixing streaks is It is characterized in that it is adapted to be fitted into a fitting groove or a fitting hole formed in the mounting bracket.
[0036]
The ring-shaped mounting bracket and the U-shaped fixing streaks are as described in the description of the pile head joint structure according to claims 1 to 7.
[0037]
According to a ninth aspect of the present invention, in the pile head joint according to the eighth aspect, the ring-shaped mounting member is formed of a plurality of members divided in a circumferential direction, and a connection portion formed at both ends of the member. It is characterized in that the pile is fixed to the outer peripheral surface of the head portion by binding.
[0038]
The pile head joint fitting according to the ninth aspect is applied to the pile head joint structure according to the third aspect, and the divided members are tied together by using a high-strength bolt or the like to thereby provide a mounting bracket. It can be tightly fixed to the outer peripheral surface of the pile head while introducing tension in the circumferential direction.
[0039]
The construction method of a pile head joint according to claim 10 of the present application is a method of constructing a foundation pile, comprising: a pile head of a pile steel pipe and an upper concrete structure; In the method of constructing a pile head joint portion to be joined via an anchoring bar, the lower end bent portion of the U-shaped anchoring bar serving as the anchoring bar is formed with a gap formed in the circumferential direction of a ring-shaped mounting bracket at intervals. After fitting into the mating groove or the fitting hole and attaching the ring-shaped mounting bracket to the outer peripheral portion or the upper end portion of the pile head, the concrete constituting the concrete structure is poured, and The upper part is fixed in the concrete.
[0040]
Claim 10 provides one of the construction methods for forming the pile head joint structure according to claims 1 to 7, and specifically forms the pile head joint structure according to claims 1 to 7. Various aspects are conceivable for the method.
[0041]
BEST MODE FOR CARRYING OUT THE INVENTION
1 and 2 show one embodiment of the present invention.
[0042]
The ring-shaped mounting bracket 1 constituting the pile head joint bracket is composed of two arc-shaped members 1a and 1b obtained by dividing the ring into two parts, and as shown in FIG. 2, the pile head of the pile steel pipe 10 is sandwiched from both sides. Thus, the connection portions 2 provided at both ends of the members 1a and 1b are bolted together using the bolt holes 2a, so that the connection portions 2 can be attached to the pile head.
[0043]
A plurality of U-shaped fitting grooves 3 are formed at predetermined intervals on the inner peripheral surface of the ring-shaped mounting member 1 composed of the members 1a and 1b. The lower end bent portion of the streak 5 is fitted, and in this state, as shown in FIG. 2 (c), the mounting bracket 1 is attached to the outer peripheral surface of the pile steel pipe 10 so that the U-shaped fitting fitted to the fitting groove 3 is achieved. The anchoring streak 5 is attached in a form sandwiched between the outer peripheral surface of the pile head and the inner peripheral surface of the mounting bracket 1.
[0044]
By filling the fitting groove 3 with a grout material such as mortar or synthetic resin as necessary, the hardening of the fitting groove 3 eliminates backlash of the U-shaped fixing streaks 5 and makes it possible to transmit stress more smoothly. .
[0045]
Further, on the outer peripheral surface of the pile head of the pile steel pipe 10, two steel members are circumferentially attached by welding or the like to form convex portions 11 a and 11 b, and these convex portions are formed on the inner peripheral surface of the mounting bracket 1. Two recesses 4a and 4b are formed at positions corresponding to 11a and 11b, and can be fitted to each other.
[0046]
In this example, as shown in FIG. 2 (a), the recesses 4a and 4b of the mounting bracket 1 are tapered so that the fitting with the projections 11a and 11b is smooth. Thereby, manufacturing dimensional errors can be absorbed.
[0047]
Furthermore, by providing the protrusions 11a and 11b and the recesses 4a and 4b in such a manner that they can be fitted to each other, they can be used for positioning, or can be used for temporary fixing or temporary support during mounting.
[0048]
In addition, since the position of the mounting bracket 1 can be corrected along these fitting portions, the workability in the arrangement of reinforcing bars or the like in the upper concrete structure such as footing can be improved. Stress transmission between the mounting bracket 1 and the pile steel pipe 10 can be achieved.
[0049]
FIG. 3 shows a part in the circumferential direction and a vertical cross section of another embodiment of the joining fitting of the present invention.
[0050]
In this example, not the fitting groove but the fitting hole 3a is formed in the mounting bracket 1, and the U-shaped fixing streak 5 is fitted into the fitting hole 3a from below. In this state, the U-shaped fixing streak 5 may fall off. Therefore, the U-shaped fixing streak 5 may be fixed with a nut 6 as shown in FIG. It is conceivable to attach a cover plate 7 for closing the lower end opening of the fitting hole 3a as shown in FIG.
[0051]
In the drawings, reference numeral 4 corresponds to the concave portions 4a and 4b in the embodiment of FIGS. 1 and 2, and when the convex portion on the pile steel pipe side is one, the concave portion 4 on the mounting bracket 1 side is also one. Article.
[0052]
FIG. 4 shows a further embodiment of the metal joint according to the present invention. In the example of FIG. 3, both ends extending above the U-shaped fixing streak 5 are arranged in the circumferential direction. In the example of No. 4, the case where the both ends extending above the U-shaped fixing streaks 5 are arranged in the radial direction is suitable for the case where it is necessary to increase the number of fixing streaks in the form of double bars.
[0053]
FIG. 5 shows still another embodiment of the joint fitting according to the present invention. The joint fitting 1 to which the plurality of U-shaped fixing streaks 5 are attached is attached to a pile head of a pile steel pipe 10 to which the fitting 1 is attached. A fitting recess 8 corresponding to the entire height is formed, and the mounting bracket 1 is fitted into the fitting recess 8 to be mounted.
[0054]
Also in this case, a ring obtained by dividing the ring into two parts is used as the mounting bracket 1, and the mounting bracket 1 is fixed to the pile head by fastening with bolts or the like, or each member constituting the mounting bracket 1 is directly bolted to the pile head. For example, the mounting method of the mounting bracket 1 is arbitrary.
[0055]
FIG. 6 shows a main part of still another embodiment of the joint fitting according to the present invention, and FIG. 6 (a) shows a ring-shaped fitting 1 completely penetrated into the upper end of the pile steel pipe 10 by welding. FIG. 6B is a cross-sectional view of a case where the fixing is performed by the part 13), and FIG. FIG. 6D is a cross-sectional view when the ring-shaped mounting bracket 1 is fixed to the outer peripheral portion of the pile steel pipe 10 by fillet welding (welded portion 14).
[0056]
In these, a plurality of U-shaped fitting grooves 3 are formed at intervals on the outer peripheral surface side of the mounting bracket 1, and the lower end bent portion of the U-shaped fixing streak 5 is fitted into the fitting groove 3, By pressing the fitting portion with the cover plate 9, the U-shaped fixing streaks 5 are prevented from coming out from the side.
[0057]
As shown in FIG. 6 (c), the cover plate 9 may be one in which the ends of members 9a and 9b obtained by dividing the ring into two are fastened by tightening bolts or the like, or the mounting position of each U-shaped fixing streak 5 Each time, the bolt 12 may be used to fasten to the mounting bracket 1 or the pile steel pipe 10.
[0058]
As described in the embodiment of FIGS. 1 and 2, in each of the above embodiments, the U-shaped fixing streak 5 is provided in the fitting groove 3 or the fitting hole 3 a where the U-shaped fixing streak 5 is fixed. Mortar or a grout material such as resin is used to fill the gap between the U-shaped fixing streaks 5 and the triaxial restraint effect is exerted. Stress transmission.
[0059]
Further, when the nut 6 and the like are omitted by filling the grout material, the labor for tightening the nut 6 becomes unnecessary, and the workability is further improved.
[0060]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, a pile steel pipe and a concrete structure of an upper part can be joined with a small number of parts without welding in principle, and also needing no special joining hardware, stable quality and inexpensive workability. Good pile head joint is obtained.
[0061]
By attaching a U-shaped bent-up fixing metal fitting as a pile head connecting material, high resistance to tensile force can be obtained, and it was fitted and fitted in a U-shaped fitting groove. In this case, a high proof stress can be exhibited not only for the tensile force but also for the compressive force.
[Brief description of the drawings]
FIGS. 1A and 1B show an embodiment of a joint fitting (only a fitting part) according to the present invention, wherein FIG. 1A is a plan view and FIG.
2A is a sectional view taken along line AA of FIG. 1, FIG. 2B is a developed view taken along line BB of FIG. 1, and FIG. 2C is a sectional view of a pile steel pipe of the mounting bracket (two-dot chain line) of FIG. FIG. 3D is a front view showing a form of joining to a pile head, and FIG.
FIGS. 3A and 3B show another embodiment of the joining fitting according to the present invention, wherein FIG. 3A is a perspective view showing a part of the joining fitting, and FIG. 3B is a vertical sectional view thereof.
4A and 4B show still another embodiment of the metal joint in the present invention, wherein FIG. 4A is a perspective view showing a part of the metal joint, and FIG. 4B is a vertical sectional view thereof.
FIGS. 5A and 5B show still another embodiment of the joint fitting according to the present invention, wherein FIG. 5A is a front view showing a part of the joint fitting, and FIG. It is a vertical sectional view shown.
FIG. 6 shows a main part of still another embodiment of the joint fitting according to the present invention, in which (a) shows an embodiment in which the fitting is fixed to the upper end of the pile steel pipe by complete penetration welding. A vertical sectional view, (b) is a front view thereof, (c) is a plan view of a cover plate, and (d) is a vertical sectional view showing an embodiment in which a mounting bracket is fixed to an outer peripheral portion of a pile steel pipe by fillet welding. It is.
7A and 7B show a conventional reinforcing bar cage system, in which FIG. 7A is a horizontal sectional view and FIG. 7B is a vertical sectional view.
8 (a) is a horizontal sectional view, FIG. 8 (b) is a vertical sectional view, and FIG. 8 (c) is an enlarged view of a welded portion of a fixing streak.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Mounting bracket, 1a, 1b ... Component parts of a mounting bracket, 2 ... Connecting part, 2a ... Bolt hole, 3 ... Mating groove, 3a ... Mating hole, 4, 4a, 4b ... Recess, 5 ... U-shaped Anchoring streaks, 6 nuts, 7 cover plates, 8 fitting recesses, 9 cover plates, 10 pile steel pipes, 11a, 11b projections, 12 bolts, 13 welds (complete penetration welding), 14: welded portion (fillet welding), 21: pile steel pipe, 22: steel cage, 23: footing, 24: steel bar, 25: welding

Claims (10)

A pile head joint structure in which a pile head of a pile steel pipe constituting a foundation pile and an upper concrete structure are joined via a plurality of anchoring bars extending in the pile axis direction and anchored in concrete, A plurality of U-shaped fixing streaks having a bent portion at the lower end are used as fixing streaks. A pile head joint structure, wherein a lower end bent portion of the U-shaped fixing streak is fitted and attached to a mating groove or a fitting hole. 2. The pile head joint structure according to claim 1, wherein the ring-shaped mounting member is made of a plurality of members divided in a circumferential direction, and is attached to an outer peripheral surface of the pile head. 3. The said member divided | segmented into the some direction in the circumferential direction is attached to the outer peripheral surface of the said pile head by the connection of the connection part formed in the both ends of this member. Pile head joint structure. The pile head joint structure according to claim 2 or 3, wherein irregularities are formed on an inner peripheral surface of the member divided in a circumferential direction and an outer peripheral surface of the pile head to fit each other. The fitting groove is formed on an inner peripheral surface of the ring-shaped mounting bracket, and the U-shaped fixing streak is formed between an outer peripheral surface of the pile head and an inner peripheral surface of the ring-shaped mounting bracket. The pile head joint structure according to claim 1, 2, 3, or 4, which is sandwiched between the pile heads. The pile head joint structure according to claim 1, wherein the ring-shaped mounting member is welded to an outer peripheral surface or an upper end portion of the pile head. 7. The U-shaped fixing streak is sandwiched between the ring-shaped mounting bracket and a cover plate mounted on the ring-shaped mounting bracket. The pile head joint structure described. A ring-shaped mounting bracket attached to an outer peripheral portion or an upper end portion of a pile head of a pile steel pipe constituting a foundation pile; and a plurality of U-shaped anchoring bars arranged at intervals in a circumferential direction of the mounting bracket. Wherein the lower end bent portion of the U-shaped fixing streak is fitted into a fitting groove or a fitting hole formed in the mounting fitting. The ring-shaped mounting bracket is made of a member divided into a plurality in the circumferential direction, and is fixed to the outer peripheral surface of the pile head by binding between connecting portions formed at both ends of the member. The pile head joint fitting according to claim 8, wherein: In a construction method of a pile head joint portion for joining a pile head of a pile steel pipe constituting a foundation pile and an upper concrete structure through a plurality of anchoring bars extending in the pile axis direction and anchoring in concrete, The lower end bent portion of the U-shaped fixing streak as the fixing streak is fitted in a fitting groove or a fitting hole formed at intervals in a circumferential direction of a ring-shaped mounting bracket, and the ring-shaped mounting stud is formed. After attaching a metal fitting to an outer peripheral portion or an upper end portion of the pile head, concrete forming the concrete structure is cast, and an upper portion of the anchoring bar is anchored in the concrete. Construction method of the department.

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