JPH10195868A - Fastening method for concrete pile, fastening structure and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fasten a concrete pile in a job site simply and quickly, and manufacture the concrete pile with high reliability and simply. SOLUTION: A connecting end 10b of a fastening opening part, the inner part of which is expanded from the connecting end in the cross direction is provided with plural fastening metal fittings A on the outer peripheral surface to be exposed to a connecting surface 1A of a concrete pile 1. At the time of locking the respective ends of a PC bar steel 2 to form the state where tensile stress is applied on the fastening metal fitting and connecting two concrete piles 1, with the connecting ends of the respective fastening metal fittings brought into contact with each other, the connecting surfaces 1A are opposed and pressed to each other, and a fastening element, the section of which is substantially equal to the fastening space is inserted in the fastening space formed by the fastening opening parts of two fastening metal fittings A in such a manner as to be expanded in the cross direction from the connecting ends in both inner parts, thereby fastening plural places of the outer periphery of the connecting part of the concrete piles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete pile fastening method and structure for use in ground improvement and civil engineering foundation construction, and a method for manufacturing the concrete pile.

[0002]

2. Description of the Related Art In the construction of condominiums, buildings or factories, for example, as civil engineering foundation work or for the purpose of improving the ground, the ground is appropriately spaced according to the soil quality, and A concrete pile is driven to an appropriate depth.

[0003] This concrete pile is manufactured at a certain length (standard length) at a factory, and is driven in while being sequentially tightened according to the driving depth at the time of use.

[0004] Fastening between the concrete piles is generally carried out by welding thick metal plates disposed at both ends of the concrete pile to each other. Specifically, at the concrete pile driving site,
In a state where a concrete pile to be driven is set in a driving machine, a lower end thereof is connected to an upper end of a concrete pile already driven, and each metal plate is electrically welded to each other. At this time, as shown in FIG. 8, a so-called notch (squaring) for welding is performed on the peripheral edge 20 a on the connection side of the metal plate 20, and the meat formed by welding is formed of the metal plate. Care was taken not to substantially protrude from the outer periphery.

[0005] However, when the concrete pile is connected by electric welding, there is a possibility that an operator may receive an electric shock in rainy weather, and since the welding cannot be performed in an optimum working posture, the reliability of the welded portion is reduced. Chip. In addition, in the case of this welding operation, cleaning and welding work of the welding location and subsequent slag removal operation are required, so that the driving operation is interrupted for a considerable time, and the expensive driving machine is stopped during that time. It will also be. Furthermore, a welding machine and a power source must be arranged at the site, and preparation for that is required.

In the concrete pile fastening structure described above, one end of PC steel bar is fastened to a metal plate, and the metal plates to be welded are welded to each other at their peripheral edges. PC steel bars
The transmission path of the tensile force is not linear. Therefore, when the tensile force acts, a bending stress acts on the fastening portion, and the strength of the entire concrete pile decreases around the fastening portion.

As another method of fastening a concrete pile, as shown in FIG. 9, as shown in FIG. 9, an end of a concrete pile to be fastened is formed in a band-like concave shape. 21 is formed, and a band 22 made of a thick plate is wound around the concave portion 21 and fastened. In such a case, a large hydraulic device is required to tighten the band. In some cases, play is likely to occur in the fastening portion, and complete fastening may not be performed. Further, in the case of fastening by such a method, as shown in FIG. 9, at the fastening portion, the band protrudes outward in the radial direction, and comes into contact with the surrounding earth and sand at the time of driving, so that resistance is preferable. Absent.

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation, and a concrete pile fastening method and a fastening structure which can be easily and quickly fastened on site, and which can be manufactured with high reliability and at low cost. And to provide a manufacturing method.

[0009]

According to the first aspect of the present invention, there is provided a method for fastening a concrete pile, comprising the steps of:
A method for longitudinally fastening between PC concrete piles buried in a concrete pile body in a state where a required number of C steel bars are subjected to a tensile stress, wherein the connecting ends of the fastening openings are So that it is exposed on the connection surface
A plurality of fasteners are provided on the outer peripheral surface of the connection portion of the concrete pile, and each end of the PC steel bar is locked and connected so that a state in which a tensile stress acts on the fastener can be formed. The connecting faces of the two concrete piles are made to face and abut with each other, and a fastener approximately equal to the fastening space is inserted into a fastening space formed by the fastening openings of the two fastening fittings that are in contact with each other. A plurality of locations on the outer periphery of the connecting portion are fastened.

The method for fastening a concrete pile according to the second aspect of the present invention is a method for fastening a PC concrete pile embedded in a concrete pile body in a state in which a required number of PC steel bars are tensilely applied in a longitudinal direction. It is a fastening method for fastening between each other in the longitudinal direction, such that the connection end of the fastening opening that is wider in the width direction than the connection end is exposed on the connection surface of the concrete pile,
A plurality of fasteners are provided on the outer peripheral surface of the connection portion of the concrete pile, and each end of the PC steel bar is locked so that a state in which a tensile stress is applied to the fastener is formed, and two concrete members are fixed. When connecting the piles, with the connecting ends of the respective fasteners abutting, the connecting surfaces of the two concrete piles to be connected face and abut, and the fastening openings of the two fasteners that are in contact with each other By inserting a fastener having a cross section substantially equal to the above-mentioned fastening space into the fastening space that is formed, the both inner sides of which extend in the width direction from the connection end, it is confirmed that a plurality of locations on the outer periphery of the connection portion of the concrete pile have been fastened. Features.

The concrete pile fastening structure according to the fourth aspect of the present invention is the concrete pile fastening structure according to the present invention, wherein the PC bars are buried in the concrete pile body in a state where a required number of PC steel bars are subjected to tensile stress in the longitudinal direction. In the longitudinal direction, the connection end of the fastening opening on the connection surface of the concrete pile, so that the connection end of the concrete pile is exposed on the connection surface of the concrete pile, on the outer peripheral surface of the connection portion of the concrete pile, A plurality of fasteners are embedded, and each end of the PC steel bar is locked so that a tensile stress is applied to the fasteners, and the connection surfaces of the two concrete piles to be connected face each other. Abutting and inserting a fastener substantially equal to the fastening space into a fastening space formed by the fastening openings of the two fastening fittings in contact with each other. I, characterized by being configured so as to enter into between the concrete piles.

The concrete pile fastening structure according to the fifth aspect of the present invention is a concrete pile fastening structure for a PC concrete pile embedded in a concrete pile main body in a state in which a required number of PC steel bars are subjected to tensile stress in a longitudinal direction. A fastening structure for fastening the members in the longitudinal direction, wherein a connecting end of a fastening opening whose back is wider in a width direction than a connecting end is exposed on a connecting surface of the concrete pile. A plurality of fasteners are buried on the outer peripheral surface of the connection part of the concrete pile, and each end of the PC steel bar is locked so that a state in which a tensile stress is applied to the fastener is formed. The two concrete piles to be joined face each other and the connecting faces of the concrete piles face each other with the connecting ends of the fasteners abutting. The concrete pile is inserted into a fastening space formed by the fastening openings of the two fitting metal fittings in contact with each other and having a depth that is substantially equal to the above-mentioned fastening space in both sides of the fastening space that extends in the width direction from the connection end. It is characterized in that it is configured to fasten the space.

According to the concrete pile fastening method and the fastening structure constructed as described above, at the time of fastening, the fastening is performed at the fastening openings of the fastening fittings in contact with the two concrete piles to be fastened. Pressing in (or hammering in) the child makes it easy to connect. Moreover, simply press-fit (or drive) the fastener
And the like can be performed with very simple work, so that the work can be performed in a short period of time even by a non-skilled person, and a highly reliable fastening can be performed. In addition, there is no need for equipment for this, and it can be easily implemented even in a site where electricity cannot be supplied, and the site can be selected.

Further, a method for manufacturing a concrete pile according to the invention of claim 9 is the method for manufacturing a concrete pile according to claim 7 or 8, wherein the inside of the casing has an inner shape equal to the outer shape of the concrete pile. And P
While disposing the C-bar in the longitudinal direction, at both ends thereof, the both end surfaces of the casing are provided with a strength plate as a weir except for the fastening opening of the fastening fitting, and the above-mentioned so that the tensile force can be transmitted. A fastening fitting is provided, and the fastening fitting at one end of the PC steel bar is fixed to the anchoring means fixed to the machine side, and the fastening fitting at the other end of the PC steel bar is fastened to a tension device, and thereafter, with the tension device. The method is characterized in that concrete is poured into the casing in a state where a tensile force is applied to the PC bar, and the PC bar is manufactured.

Thus, it is possible to easily and inexpensively manufacture a concrete pile excellent in the workability or functionality.

[0016]

In the concrete pile fastening method according to the first or second aspect of the present invention, as in the third aspect, the connecting end of the fastening opening according to the second aspect is connected to a T-shaped lower end. As a result, when the fastening opening is formed in a substantially T shape, the fastening space is formed in a substantially H shape, and the cross section of the fastener is formed in a substantially H shape, the functional and productivity are improved. In this respect, the configuration is also excellent.

In the concrete pile fastening structure according to the fourth or fifth aspect of the present invention, as in the sixth aspect, the fastening opening of the fourth or fifth aspect has a connecting end of the connecting portion having a T-shape. When the fastening space has a substantially H-shape and the cross-section of the fastener has a substantially H-shape, a configuration excellent in functionality and productivity is achieved. Become.

Further, in the concrete pile fastening structure according to the fifth or sixth aspect, when concrete is poured into the connecting surface according to the fifth or sixth aspect, the concrete is sufficient for positioning the fastener. If a plate having a thickness enough to have strength as a weir is arranged in such a manner that at least the fastening opening of the fastener is exposed from the plate, manufacturing becomes easy and fastening is performed. Helps to accurately and easily position the hardware.

According to a seventh aspect of the present invention, in the concrete pile fastening structure, a first positioning means for positioning is formed at a part of the fastening opening of the seventh aspect, and the connection means is provided. If the positioning second means to be locked to the first positioning means is formed on the plate, the positioning of the fastener on the connection surface is further ensured.

Further, in the method for manufacturing a concrete pile according to the ninth aspect, when the casing according to the ninth aspect is rotated after the concrete is poured, a cylindrical concrete pile is manufactured. Becomes possible.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete pile according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a view showing an entire structure of a concrete pile according to one embodiment of the present invention, FIG. 2 is an enlarged view of a fastening portion of FIG. 1, and FIG. FIG. 4 is an enlarged perspective view of FIG.

In the figure, A is a fastener for fastening a concrete pile, and this fastener A is shown in FIG.
As shown in (b), the fastening opening 10 in which the depth 10a is wider than the connection end 10b in the width direction (refer to the W direction in FIG. 5), that is, in the case of this embodiment, is referred to as a "schematic T-shape (see FIG. In FIG. 2 b, the fastening opening 10 is formed in a substantially T-shape when viewed from the fastening direction (the right end of the fastening is turned down), and the connecting end 10 b of the fastening opening 10 is shown in FIG.
As shown in (a) to (c), the concrete pile 1 (see FIG. 1) is disposed so as to be exposed at the connection surface 1A. Then, as shown in FIG. 5, the fastening opening 10 is inserted in the insertion direction (see FIGS. 1 and 5) of the fastener 11 (see FIG. 4).
(A), (c), an inclined surface 10g that moves away from the connection surface 1A as it goes further in the depth direction (in the direction of the arrow Y) is formed in a wedge hole in which the cross-sectional area of the fastening opening 10 is reduced. . Also, this fastening A is shown in FIG.
As shown in FIG. 5A, a fastener 11 is provided on the opposite side 10j of the fastening opening 10 (to the left in FIG. 5A).
4 (see FIG. 4).
), And a female screw hole 10c for tightening, which is screwed to the male screw of the tightening bolt B, is formed. Further, as shown in FIG. 5, a connecting through hole 10d for engaging one end of the PC steel bar 2 disposed in the concrete pile 1 (see FIG. 1) is shown in FIG. 5 (c). As shown in FIG. 5, on both sides of the fastening opening 10, the fastening element 11 is formed so as to face the fastening direction of the fastener 11 (see the arrow X direction in FIG. 5). Also, as shown in FIG. 5 (c), the same direction is set at the center of the groove 10e of the connecting portion 10A of the fastener A, which is a part of the connecting surface 1A, that is, at the intermediate position of the connecting through-hole 10d. An attachment hole 10f for applying a tensile force is formed so as to face. This attachment hole 10f is used when a tensile force is applied to the PC steel bar 2 in the production of a concrete pile.

As shown in FIG. 6, the fastener A may have a configuration in which one PC bar is connected to one fastener A. This fastener A is also shown in FIG. 5 with a through hole 1 for connection with a PC steel bar 2.
Except that only one 0d is provided, the other configuration is the same. 6, the same components as those in FIG. 5 are denoted by the same reference numerals.

Then, as shown in FIG. 1 or FIGS. 2A to 2C, the fastening fitting A is
Is connected to the concrete pile 1 (see FIG. 1).
Is provided so as to be exposed on the connection surface 1A.

As shown in FIG. 1, the concrete pile 1 is provided with the above-mentioned fasteners A at both ends as described above, and a tensile force is applied to the fasteners A. The ends of the PC steel bars 2 are connected. As shown in FIG. 5B and FIG. 5D which is an enlarged view of the portion, an expanded portion 2a (see FIG.
(See (d)), and the inflated portion 2a is
It is configured to engage with a receiving portion 10k formed continuously with Od, and to be connected so as to receive a tensile force acting on the PC steel bar 2 as described later. However, instead of this, the PC steel bar 2 having a thread formed at the end in the through hole 10d.
May be inserted, and a bolt may be screwed into the male screw and connected.

In this embodiment, as shown in FIG. 1 and FIG. 2, on both ends of the concrete pile 1, donut-shaped plates 3 each having an opening at the center are arranged. At the place where the fastening member A is disposed, a portion corresponding to the connection end portion 10b of the fastening member A (more precisely, a portion closer to the connection surface than the step of the connection portion 10A as shown in FIG. )
Has an opening 3a and a peripheral edge 3b bent 90 degrees to surround the outer periphery of the concrete pile 1. The slab 3 is made of a steel plate (or a stainless steel plate) having a thickness of about 1 to 3 mm, and prevents the outflow of concrete (function as a weir) when manufacturing a concrete pile 1 described later. With concrete pile 1
The connection surface 1A is provided so as to position the fastener A at a predetermined position. Further, it is desirable that the fastener A positioned at a predetermined position is fixed to the slab 3 by spot welding Q (see FIG. 2) or the like.

When the concrete pile 1 arranged as described above is driven in for strengthening the ground, the concrete pile 1 can be sequentially connected as follows. That is, as shown in FIGS. 3 and 4, in the longitudinal direction of the concrete pile 1,
The connection surfaces 1A of the two concrete piles 1 to be connected face and abut each other, that is, the connection ends 10b of the fasteners A provided on the connection surfaces 1A of the two concrete piles 1 face and abut each other. . In this state, as shown in FIG. 4, a fastening space N having a “substantially H shape” (referred to as a substantially H shape when rotated by 90 ° in FIG. 4) is formed.

Then, the fastener 11 shown in FIG. 4 is inserted into the formed fastening space N. This insertion is carried out lightly using a worker's hammer or the like, then the tightening bolt B is inserted into the tightening bolt hole 11a, and the tightening bolt B male screw is inserted into the tightening female screw hole 10c. Screw on
The fastener 11 is fixed to the fastener A so that the fastener 11 is fitted. In such a case, without using a hydraulic device, etc.
An operator can easily and reliably perform the fastening manually. The bolt B also functions as a stopper for the fastener 11.

Although not shown, the fastener 11 may be inserted into the fastener A by using a portable hydraulic device.

When the fastener 11 is inserted into the fastening space N formed around the concrete pile 1 as described above, the two concrete piles 1
Are fastened in a single shape with their axes aligned. And
Since the PC steel bars 2 in each concrete pile 1 are connected linearly via the fasteners A, each of the PC steel bars 2 is connected.
Is transmitted linearly, resulting in a configuration excellent in strength.

By the way, the concrete pile 1 is
It is manufactured through the following steps. That is, first, as shown in FIGS. 7A and 7B, two cylindrical cylinders of a cylindrical reinforcing barge C1 having a slightly larger diameter and a cylindrical reinforcing barge C2 having a smaller diameter. Reinforced palanquin C is formed.

Next, as shown in FIG. 7 (c), a small-diameter reinforcing bar peg C2 is inserted into the large-diameter reinforcing bar peg C1 in a nesting manner, so that the entire length is equal to that of the concrete formwork. 7 (see FIG. 7 (h)). At this time, the slab 3 is disposed on one end face of the slab 3 so that its peripheral edge 3b is located on the outer periphery of the reinforcing bar peg C, and a fastening fitting A is provided in the opening 3a of the slab 3.
Are disposed so that the entire length L of the casing 13 (see FIG. 7 (h)) is inserted into the through hole 10d.
PC steel bar 2 cut shorter to form an expanded portion 2a (see FIGS. 5B and 5D) at the end (the right end in the figure)
Insert At this time, as shown in FIG. 2, the edge of the opening 3a of the plate 3 is engaged with the step of the connecting portion 10A of the fastening member A, and accurate positioning is performed. Then, preferably, in this state, the fastening fitting A is fixed to the barrier plate 3 by spot welding.

Next, as shown in FIG. 7D, the PC bar 2 is inserted until the tip (the left end in the figure) of the PC bar 2 projects from the left end of the reinforcing bar peg C.

Subsequently, as shown in FIG. 7 (e), the end plate 3 on the opposite side (left side in the figure) of the reinforcing bar peg C is shown.
Is disposed so that the tip (the left end in the figure) of the PC bar 2 passes through the opening 3a of the barrier plate 3, and the through hole 10d of the other fastener A is further inserted into the tip of the PC bar 2. (See FIG. 5).

Subsequently, as shown in FIG. 7 (f), the tip of the PC steel bar 2 is attached to the expanded portion 2a (FIG. 7).
(C), see FIG. 5 (d)) to form an inflatable portion 2a at a position shorter than the overall length L of the casing 13 (see FIG. 7 (h)). Then, the fastening fitting A is arranged in a predetermined state with respect to the opening 3a of the siding board 3 later. Then, preferably, in this state, the fastening fitting A is fixed to the barrier plate 3 by spot welding.

Next, as shown in FIG. 7 (g), the mounting holes 10f for the fastening fittings A at both ends of the PC steel bar 2 connected as described above.
5 (a) and (c), an end fitting (end plate) 16 is attached via a connecting bolt 15. Then, one end face metal fitting 16 is anchored to the machine base 17 (fixing metal fitting).
17a, the other end face bracket 16 is connected to a tension device (only a tension portion for performing a tension operation is shown) 18 side, and a tensile force is applied to the PC steel bar 2.

Subsequently, as shown in FIG. 7 (h), the periphery of the reinforcing bar peg C is divided into two parts in a longitudinal direction so that both ends are closed by the slabs 3 (U-shape). Grooved)
While being surrounded by a casing 13, the sol-like cement is poured from a central space portion O of the slab 3 while rotating the casing 13.

Then, the rotation is continued until the cement is substantially set, and the rotation is stopped when the cement is substantially set (the state in which the cement does not flow even if the rotation is stopped), and the solidification of the cement is waited.

Through the above series of steps, a concrete pile capable of performing the above-described simple and highly reliable fastening is manufactured.

The fastener A is a concrete pile 1
This is useful not only in the case of connecting the steel bars but also in the production, when applying a tensile force to the PC steel bar 2.

[0042]

According to the method for fastening a concrete pile according to the present invention, however, there is no need for equipment such as an electric welding machine as in the prior art, and there is no need for consideration of electric leakage even in rainy weather, and furthermore, the skill is improved. Even if it is not a person, it can be fast and easily fastened.

Further, according to the concrete pile fastening structure of the present invention, the connected PC steel bars can be fastened linearly through the fastening fittings, so that the stress can be transmitted smoothly. Since the fastening is performed by a mechanical structure, the fastening can be performed in a highly reliable state. Further, since the fastening portion can be simplified, the fastening structure can be configured at a lower cost than the conventional one.

Furthermore, according to the concrete pile manufacturing method of the present invention, it is possible to easily and inexpensively implement a concrete pile capable of implementing the excellent concrete pile fastening structure and fastening method as described above. it can.

[Brief description of the drawings]

FIG. 1 is a view showing a state before a concrete pile according to one embodiment of the present invention is to be fastened.

FIG. 2 is an enlarged view showing a fastening portion of one concrete pile in FIG. 1, (a) is a side view in which a left half is sectioned, (b) is a view as seen from a connection surface side, (c) FIG. 4 is a partially enlarged view showing a detailed configuration of a fastening end of a fastening fitting of FIG.

FIG. 3 is an enlarged side view showing a fastening state after fastening at a fastening portion shown in FIG. 1;

FIG. 4 is an enlarged perspective view showing a state before fastening at a fastening portion.

5A and 5B are diagrams showing a configuration of the fastening fitting, wherein FIG. 5A is a side view of the fastening fitting, FIG. 5B is a view of the fastening fitting viewed from the direction of arrows bb in FIG. c) is a view of (b) as viewed from the cc direction (connection surface side), and (d) is an expanded portion (see a solid line) of a PC steel bar shown in (b) and a receiving portion of a through hole (see a two-dot chain line) FIG. 2 is an enlarged view of the engagement state of FIG.

6A and 6B are diagrams showing a configuration of a fastener having a configuration different from that of FIG. 5, wherein FIG. 6A is a side view of the fastener and FIG.
The figure seen from the b arrow direction (the fastening part is a side), (c) is the figure which looked at (b) from the cc direction (connection surface side), and (d) is (a) the dd direction. FIG.

FIG. 7 is a diagram showing steps of a method for manufacturing the concrete pile shown in FIG.

FIG. 8 is a view showing a fastening portion fastened by conventional electric welding.

FIG. 9 is a view showing a fastening portion fastened by a conventional band.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Concrete pile 1A ... Connection surface 2 ... PC steel bar 3 ... Seki board 10 ... Fastening opening 11 ... Fastener A ... Fastening fitting N ... Fastening space

Claims (10)

[Claims] 1. A fastening method for fastening longitudinally between PC concrete piles buried in a concrete pile body in a state where a required number of PC steel bars are subjected to a tensile stress in a longitudinal direction, A plurality of fasteners are arranged on the outer peripheral surface of the connection portion of the concrete pile so that the connection end of the fastening opening is exposed on the connection surface, and a state in which a tensile stress acts on the fastener can be formed. So that each end of the PC bar is locked,
The connecting surfaces of the two concrete piles to be connected face each other and abut against each other, and a fastener substantially equal to the fastening space is inserted into a fastening space formed by the fastening openings of the two fastening fittings that are in contact with each other. A method for fastening a concrete pile, comprising fastening a plurality of locations on the outer periphery of a connection portion of the concrete pile. 2. A fastening method for fastening longitudinally between PC concrete piles buried in a concrete pile body in a state where a required number of PC steel bars are subjected to tensile stress in a longitudinal direction, A plurality of fastening fittings are arranged on the outer peripheral surface of the connection portion of the concrete pile so that the connection end of the fastening opening portion whose back is wider in the width direction than the connection end is exposed on the connection surface of the concrete pile. When locking each end of the PC steel bar so that a tensile stress is applied to the fastener, and connecting two concrete piles,
With the connecting ends of the fasteners abutting, face the connecting surface of the two concrete piles to be connected.
By inserting a fastener having a cross section substantially equal to the above-mentioned fastening space, into the fastening space formed by the fastening openings of the two fastening fittings that are in contact with each other and formed in the width direction from both ends in the width direction from the connection end. A method for fastening a concrete pile, comprising fastening a plurality of locations on the outer periphery of a connection portion of the concrete pile. 3. The fastening opening has a substantially T-shape, and the fastening space has a substantially H-shape so that a connection end of the fastening opening is a lower end of the T-shape. Is substantially H-shaped.
Or the method of fastening a concrete pile according to 2. 4. A fastening structure for fastening longitudinally between PC concrete piles embedded in a concrete pile body in a state where a required number of PC steel bars are applied with tensile stress in a longitudinal direction, A plurality of fasteners are buried on the outer peripheral surface of the connection part of the concrete pile so that the connection end of the fastening opening is exposed on the connection face of the concrete pile on the connection face of the concrete pile. Each end of the PC steel bar is locked so that a state in which a tensile stress is applied is formed, and the connection surfaces of two concrete piles to be connected face and abut with each other. The concrete pile is fastened by inserting a fastener substantially equal to the fastening space into the fastening space formed by the portion. Fastening structure of concrete pile to be. 5. A fastening structure for fastening longitudinally between PC concrete piles embedded in a concrete pile main body in a state where a required number of PC steel bars are subjected to tensile stress in a longitudinal direction, A fastening fitting is provided on the outer peripheral surface of the connecting portion of the concrete pile such that the connecting end of the fastening opening, which is wider in the width direction than the connecting end, is exposed on the connecting surface of the concrete pile. A plurality of concrete piles which are to be buried and which are to be connected to each other by locking each end of the PC steel bar so that a tensile stress is applied to the fastener and connecting the two concrete piles to each other. The connecting surfaces of the concrete piles face and abut each other in a state where they are in contact with each other. There the fastening space that has spread in the width direction than the connecting end, by the cross-section is inserted substantially equal fastening element into the fastening space, the fastening structure of the concrete pile, characterized by being configured so as to enter into between the concrete piles. 6. A cross-section of the fastener, wherein the fastening opening has a substantially T-shape and the fastening space has a substantially H-shape such that a connection end of the fastening opening is a lower end of the T-shape. Is substantially H-shaped.
Or the fastening structure of the concrete pile according to 5. 7. A connecting plate having a thickness sufficient for positioning a fastener and providing strength as a weir when concrete is poured into the connection surface, at least a fastening opening of the fastener. 7. The concrete pile fastening structure according to claim 5, wherein the concrete pile is arranged so as to be exposed from the slab. 8. A positioning first means for positioning is formed in a part of said fastening opening, and said second positioning means is formed on said siding plate to be locked by said first positioning means. The concrete pile fastening structure according to claim 7, characterized in that: 9. The method for manufacturing a concrete pile according to claim 7, wherein a PC steel bar is disposed in a longitudinal direction in a casing having an inner shape equal to the outer shape of the concrete pile, and at both ends thereof. A casing plate having strength as a weir except for the fastening opening of the fastening fitting, and the fastening fitting so that a tensile force can be transmitted;
The fastening fitting at one end of the C-bar was fixed to the anchor means fixed to the machine base side, and the fastening fitting at the other end of the PC-bar was fastened to the tensioning device, and then a tensile force was applied to the PC bar by the tensioning device. A method for producing a concrete pile, characterized in that concrete is poured into the casing in a state and is produced. 10. The method according to claim 9, wherein the casing is rotated after pouring concrete.