JP6761168B2 - Manufacturing method of concrete pile and concrete pile - Google Patents

Description

The present disclosure relates to concrete piles and methods for manufacturing concrete piles.

Off-the-shelf concrete piles generally have a hollow cylindrical shape. Some concrete piles are called concrete piles with outer shell steel pipes (SC piles). SC piles contain concrete and have a cylindrical pile body having a hollow part and the outer peripheral surface of the pile body. It is composed of an outer shell steel pipe that covers it (see, for example, Patent Document 1).

Japanese Patent No. 5265447

In the case of a hollow cylindrical concrete pile, when it is deformed by the action of bending moment or shearing force, the concrete peels off from the inner peripheral surface of the pile body, and the bending strength and shearing strength sharply decrease. There is a problem that it is easy. This problem can occur not only in ordinary concrete piles but also in SC piles.
In view of the above circumstances, an object of at least one embodiment of the present invention is to provide a concrete pile and a method for manufacturing a concrete pile having improved bending strength and shear strength.

(1) The concrete pile according to at least one embodiment of the present invention is
A cylindrical pile body that contains concrete and has a hollow part,
A metal exfoliation suppression wall arranged in the hollow portion of the pile main body and curved along the inner peripheral surface so as to be in contact with the inner peripheral surface of the pile main body.
Equipped with a,
The exfoliation suppression wall has a substantially cylindrical shape, has an outer diameter larger than the inner diameter of the inner peripheral surface of the pile main body in the free state, and has a diameter reduced in the pile main body from the free state. the inner peripheral surface of the pile body portion to bias radially outward of the pile body portion that has been elastically contacts.

According to the above configuration (1), the metal peeling prevention wall is arranged in the hollow portion of the pile main body and is in contact with the inner peripheral surface of the pile main body. Therefore, when the pile body is deformed by a bending moment or a shearing force acting on the pile body, the peeling suppression wall prevents a part of the pile body from peeling off from the inner peripheral surface of the pile body. Will be done. As a result, according to the above configuration (1), the bending proof stress and the shearing proof stress can be improved as compared with the conventional case.
Then, according to the above configuration (1), the peeling suppression wall is elastically in contact with the inner peripheral surface of the pile main body so as to urge the pile main body outward in the radial direction. For this reason, even when the pile body is deformed, it is possible to prevent a gap from being formed between the inner peripheral surface of the pile body and the peeling suppression wall, and the peeling suppression wall prevents a part of the pile body from peeling off. It can be surely suppressed. As a result, according to the above configuration (1), the bending proof stress and the shearing proof stress can be improved as compared with the conventional case.

(2) In some embodiments, in the above configuration (1),
An outer shell steel pipe that covers the outer peripheral surface of the pile body is further provided.

The concrete pile having the above configuration (2) is a concrete pile with an outer shell steel pipe provided with an outer shell steel pipe. Concrete piles with outer shell steel pipes have higher bending strength and shear resistance than ordinary concrete piles due to having outer shell steel pipes, but from the inner peripheral surface of the pile body due to the metal peeling prevention wall. By suppressing the peeling of a part of the pile main body, the bending strength and the shearing strength can be improved as compared with the conventional case.

(3) In some embodiments, Oite to the above configuration (1) or (2),
The peeling suppression wall has a first portion and a second portion that is located at a position different from the first portion in the axial direction of the pile main body portion and is thicker than the first portion.

According to the above configuration ( 3 ), by arranging the second portion, which is thicker than the first portion, in the region where a larger bending moment or shearing force is applied, the pile body is in the region where a larger bending moment or shearing force is applied. It is possible to prevent a part of the portion from peeling off. As a result, according to the above configuration ( 3 ), the bending proof stress and the shearing proof stress can be improved as compared with the conventional case.

( 4 ) In some embodiments, in any one of the above configurations (1) to ( 3 ),
Further, a diameter reduction suppressing portion capable of suppressing the reduction of the radius of curvature of the peeling suppressing wall is provided.

When the pile body is deformed by bending moment or shearing force, if the force acts from the pile body and the radius of curvature of the wall is reduced, the inner peripheral surface of the pile body and the pile body are suppressed from peeling. There will be a gap between it and the wall. In this regard, according to the above configuration ( 4 ), the diameter reduction suppressing portion suppresses the reduction of the radius of curvature of the peeling suppressing wall, so that a gap is generated between the inner peripheral surface of the pile main body and the peeling suppressing wall. Is suppressed. As a result, the peeling suppression wall can prevent a part of the pile main body from peeling off, and the bending strength and the shearing strength can be improved as compared with the conventional case.

( 5 ) In some embodiments, in the above configuration ( 4 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion projects from the first side edge portion inward in the radial direction of the pile body portion, and is a protrusion capable of contacting the edge of the second side edge portion in the circumferential direction of the pile body portion. Has.

According to the above configuration ( 5 ), since the edge of the second side edge portion abuts on the protrusion, it is possible to suppress the reduction of the radius of curvature of the peeling suppression wall with a simple configuration.

( 6 ) In some embodiments, in the above configuration ( 5 ),
The protrusion has an L-shaped cross section in the cross section of the pile body portion, and forms a recess that can accept the edge of the second side edge portion.

According to the above configuration ( 6 ), since the edge of the second side edge is received in the recess, when the radius of curvature of the exfoliation suppression wall is to be reduced, the edge of the second side edge becomes a protrusion. Be sure to contact. Therefore, the reduction of the radius of curvature of the peeling suppression wall can be reliably suppressed.

( 7 ) In some embodiments, in the above configuration ( 4 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
At least one first engaging portion protruding from the first side edge portion inward in the radial direction of the pile body portion,
With at least one second engaging portion protruding from the second side edge portion toward the radial outer side of the pile body portion,
Have,
The first engaging portion and the second engaging portion are
When the second side edge portion is about to be displaced relative to the first side edge portion so as to reduce the radius of curvature of the exfoliation suppressing wall, the second side edge portion comes into contact with each other and the second side with respect to the first side edge portion. A contact surface that limits the relative displacement of the edges,
When the second side edge portion is about to be displaced relative to the first side edge portion so as to increase the radius of curvature of the exfoliation suppressing wall, the second side edge portion slides with each other and the second side edge portion with respect to the first side edge portion. A sliding surface that allows relative displacement of the side edges,
Have.

According to the above configuration ( 7 ), when the second side edge portion is about to be displaced relative to the first side edge portion so that the radius of curvature of the peeling suppression wall becomes smaller, the first engaging portion and the second engagement portion are engaged. Since the contact surfaces of the joints are in contact with each other, it is possible to suppress the reduction of the radius of curvature of the peeling suppression wall with a simple configuration. It is possible to suppress the reduction of the radius of curvature of the exfoliation suppression wall.
On the other hand, when the second side edge portion is about to be displaced relative to the first side edge portion so that the radius of curvature of the peeling suppression wall becomes large, the sliding surfaces of the first engaging portion and the second engaging portion become By sliding on each other, an increase in the radius of curvature of the exfoliation suppression wall is allowed. As a result, the peeling suppression wall can be brought into contact with the inner peripheral surface of the pile main body with a simple configuration.

( 8 ) In some embodiments, in the above configuration ( 7 ),
The at least one first engaging portion includes a plurality of first engaging portions arranged in the circumferential direction of the pile body portion.
The at least one second engaging portion includes a plurality of second engaging portions arranged in the circumferential direction of the pile body portion.

According to the above configuration ( 8 ), a plurality of first engaging portions and a plurality of second engaging portions arranged in the circumferential direction of the pile main body portion are provided, and the plurality of first engaging portions and the plurality of second engaging portions are provided. Of the second engaging portions, the contact surfaces of the first engaging portion and the second engaging portion, which are appropriately selected, come into contact with each other so that there is no gap with respect to the inner peripheral surface of the pile main body. The exfoliation suppression wall can be brought into contact.

( 9 ) In some embodiments, in the above configuration ( 8 ),
The first engaging portion and the second engaging portion have a cross-sectional shape of a right triangle when viewed in cross section of the pile body portion.

According to the above configuration ( 9 ), the first engaging portion and the second engaging portion have a right-angled triangular cross-sectional shape, and a simple configuration suppresses the reduction of the radius of curvature of the peeling suppression wall. be able to.

( 10 ) In some embodiments, in the above configuration ( 4 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
The first fixing base fixed to the first side edge portion and
A second fixing base fixed to the second side edge,
A bolt extending between the first fixing base and the second fixing base,
It has a diameter reduction suppressing nut that is screwed into the bolt and limits the reduction of the distance between the first fixing base and the second fixing base.

According to the above configuration ( 10 ), peeling is suppressed by a simple configuration by limiting the reduction of the distance between the first fixing base and the second fixing base by using bolts and diameter reduction suppressing nuts. It is possible to suppress the reduction of the radius of curvature of the wall.

( 11 ) In some embodiments, in the above configuration ( 4 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is arranged inside the peeling suppressing wall in the radial direction of the pile body portion so as to be in contact with the peeling suppressing wall, and is composed of a spiral member having a spiral shape.

According to the above configuration ( 11 ), the spiral member having a spiral shape can suppress the reduction of the radius of curvature of the exfoliation suppressing wall with a simple configuration.

( 12 ) In some embodiments, in the above configuration ( 4 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
A bag arranged inside the peeling prevention wall in the radial direction of the pile body, and
With the water filled in the bag,
Have.

According to the above configuration ( 12 ), the bag filled with water can suppress the reduction of the radius of curvature of the exfoliation suppression wall with a simple configuration.

( 13 ) In some embodiments, in any one of the above configurations (1) to ( 12 ),
A reduced diameter portion capable of reducing the radius of curvature of the exfoliation suppressing wall is further provided.

According to the above configuration ( 13 ), the radius of curvature of the peeling suppression wall can be reduced by the diameter reduction portion, and the peeling suppression wall can be easily arranged in the hollow portion of the pile main body portion.

( 14 ) In some embodiments, in the above configuration ( 13 ),
The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The reduced diameter portion is
The first fixing base fixed to the first side edge portion and
A second fixing base fixed to the second side edge,
A bolt extending between the first fixing base and the second fixing base,
A reduced diameter nut screwed into the bolt and capable of reducing the distance between the first fixing base and the second fixing base together with the bolt.
Have.

According to the above configuration ( 14 ), by using bolts and reduced diameter nuts to reduce the distance between the first fixing base and the second fixing base, the peeling prevention wall can be easily configured. The radius of curvature of can be reduced. As a result, according to the above configuration ( 14 ), the peeling suppression wall can be easily arranged in the hollow portion of the pile main body portion.

( 15 ) The method for manufacturing a concrete pile according to at least one embodiment of the present invention is as follows.
A pile body preparation process that prepares a cylindrical pile body that includes concrete and has a hollow part,
A metal substantially cylindrical peeling suppression wall having a first side edge portion and a second side edge portion , which has an outer diameter larger than the inner diameter of the inner peripheral surface of the pile body portion in a free state. The process of preparing the peeling prevention wall and
A diameter reduction step of bending the exfoliation suppressing wall to a reduced state that can be inserted into the hollow portion so that the first side edge portion and the second side edge portion overlap each other.
A restraining step of restraining the peeling suppressing wall so that the peeling suppressing wall maintains the reduced state, and
After the restraint step, an insertion step of inserting the peeling suppression wall in the reduced state into the pile body portion, and
After the insertion step, the restraint of the peeling suppression wall is released, and the peeling suppression wall is urged toward the radial outer side of the pile main body in a state where the diameter is reduced from the free state. The diameter expansion process that elastically contacts the inner peripheral surface of the main body,
To be equipped.

According to the above configuration ( 15 ), the peeling suppression wall is restrained in a reduced state and inserted into the hollow portion of the pile main body, and by releasing the restraint, the peeling is curved so as to be in contact with the inner peripheral surface of the pile main body. The restraining wall can be easily arranged in the hollow portion of the pile main body.
Then, in the concrete pile manufactured by the concrete pile manufacturing method of the above configuration ( 15 ), when the pile main body is deformed by the bending moment or the shearing force, the pile main body is formed from the inner peripheral surface of the pile main body. It is suppressed that a part of the concrete is peeled off. As a result, the bending strength and shearing strength of the concrete pile can be improved as compared with the conventional case.

( 16 ) In some embodiments, in the above configuration ( 15 ),
In the restraining step, both ends of the peeling suppression wall are restrained by the restraining means in the reduced state.
In the insertion step, the peeling suppression wall restrained by the restraining means is inserted into the hollow portion of the pile body portion.
In the diameter expansion step, the restraint of the exfoliation suppressing wall by the restraining means is released.

According to the above configuration ( 16 ), both ends of the peeling suppression wall in the axial direction are restrained by restraining means, and the restrained peeling suppression wall is inserted into the hollow portion of the pile body, so that the peeling suppression wall can be easily inserted. can do. Further, in the diameter expanding step, the peeling suppression wall can be easily brought into contact with the inner peripheral surface of the pile main body by releasing the restraint by the restraining means.

According to at least one embodiment of the present invention, there is provided a method for manufacturing a concrete pile and a concrete pile having improved bending strength and shear strength as compared with the conventional case.

It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on 1st Embodiment of this invention. It is a schematic cross-sectional view along the line II-II in FIG. It is a perspective view which shows typically the peeling prevention wall applied to the concrete pile with the outer shell steel pipe of FIG. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on 2nd Embodiment of this invention. It is a schematic cross-sectional view along the VV line in FIG. It is a perspective view which shows typically the peeling prevention wall applicable to the concrete pile with the outer shell steel pipe which concerns on 3rd Embodiment of this invention. FIG. 6 is a perspective view schematically showing a state in which the peeling suppression wall of FIG. 6 is reduced in diameter. It is the schematic cross-sectional view of the concrete pile with the outer shell steel pipe which concerns on 4th Embodiment of this invention, and the circle in the figure shows a part enlarged. It is the schematic cross-sectional view of the concrete pile with the outer shell steel pipe which concerns on 5th Embodiment of this invention, and the circle in the figure shows a part enlarged. It is the schematic cross-sectional view of the concrete pile with the outer shell steel pipe which concerns on 6th Embodiment of this invention, and the circle in the figure shows a part enlarged. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on 7th Embodiment of this invention. FIG. 5 is a schematic cross-sectional view taken along the line XII-XII in FIG. FIG. 5 is a perspective view schematically showing a diameter reduction suppressing portion applied to a concrete pile with an outer shell steel pipe of FIG. It is a perspective view which shows typically the diameter shrinkage suppressing part applicable to the concrete pile with the outer shell steel pipe which concerns on 8th Embodiment of this invention. FIG. 5 is a cross-sectional view schematically showing a pitch determining member together with the spiral member of FIG. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on 9th Embodiment of this invention. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on tenth embodiment of this invention. It is sectional drawing which shows typically the bag applicable to the concrete pile with the outer shell steel pipe which concerns on 11th Embodiment of this invention. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on the twelfth embodiment of this invention. It is a schematic vertical sectional view of the concrete pile with the outer shell steel pipe which concerns on 13th Embodiment of this invention. It is an enlarged view of a part of the cross section of the concrete pile with the outer shell steel pipe which concerns on 14th Embodiment of this invention. It is a schematic vertical sectional view of the prestressed concrete pile which concerns on 15th Embodiment of this invention. It is a flowchart which shows the schematic procedure of the manufacturing method of the concrete pile which concerns on the 16th Embodiment of this invention. It is a figure for demonstrating an example of a restraint process. It is a figure for demonstrating an example of a restraint process. It is a figure for demonstrating an example of a restraint process. It is a figure for demonstrating an example of a restraint process.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention to this, but are merely explanatory examples. Absent.
For example, expressions that represent relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a state of relative displacement with tolerances or angles and distances to the extent that the same function can be obtained.
For example, expressions such as "same", "equal", and "homogeneous" that indicate that things are in the same state not only represent exactly the same state, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the state of existence.
For example, an expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion or chamfering within a range where the same effect can be obtained. The shape including the part and the like shall also be represented.
On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions that exclude the existence of other components.

[First Embodiment]
FIG. 1 is a vertical cross-sectional view schematically showing the configuration of a concrete pile with an outer shell steel pipe (hereinafter, also referred to as SC pile) 1a according to the first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. FIG. 3 is a perspective view schematically showing the exfoliation suppression wall 3a applied to the SC pile 1a.

As shown in FIG. 1, the SC pile 1a has a pile main body portion 5, an outer shell steel pipe 7, a pair of end plates 9, and a peeling suppression wall 3a.
The pile body 5 is made of concrete. The pile body portion 5 has a cylindrical shape and has a hollow portion 11 extending in the axial direction. The hollow portion 11 is a cylindrical cavity and penetrates the pile main body portion 5.

The outer shell steel pipe 7 has a cylindrical shape and covers the outer peripheral surface of the pile main body 5. The outer shell steel pipe 7 is made of metal, for example, a rolled steel material for general structure. The outer shell steel pipe 7 has, for example, an outer diameter of 300 mm or more and 1500 mm or less, and the outer diameter of the outer shell steel pipe 7 corresponds to the outer diameter of the SC pile 1a. Further, the outer shell steel pipe 7 has a wall thickness of, for example, 4.5 mm or more and 25 mm or less.

Each of the pair of end plates 9 has a ring shape and covers both end faces of the pile main body 5. However, the end plate 9 has an opening connected to the hollow portion 11, and the hollow portion 11 is not covered by the end plate 9. The end plate 9 is made of metal, for example, made of rolled steel for general structure. The pair of end plates 9 are welded to both ends of the outer shell steel pipe 7.

The peeling suppression wall 3a is arranged in the hollow portion 11 of the pile main body portion 5 and is curved along the inner peripheral surface 13 so as to be in contact with the inner peripheral surface 13 of the pile main body portion 5. The exfoliation suppression wall 3a is made of metal, for example, a general structural rolled steel material. The material of the peeling suppression wall 3a is not limited to the rolled steel material for general structure, and may be a shape memory alloy or a superelastic alloy.
More specifically, the exfoliation suppression wall 3a is formed by bending a metal plate or cutting a metal tube in the axial direction. Therefore, the peeling suppression wall 3a occupies a part of the hollow portion 11, but the remaining portion of the hollow portion 11 exists inside the peeling suppression wall 3a.

According to the SC pile 1a of the first embodiment described above, the metal peeling suppression wall 3a is arranged in the hollow portion 11 of the pile main body 5 and is in contact with the inner peripheral surface 13 of the pile main body 5. Therefore, when a bending moment or a shearing force acts on the pile main body 5 and the pile main body 5 is deformed, the peeling suppression wall 3a causes a part of the pile main body 5 from the inner peripheral surface 13 of the pile main body 5. Is suppressed from peeling off. As a result, according to the SC pile 1a, the bending strength and the shearing strength can be improved as compared with the SC pile which does not have the peeling suppression wall 3a.

Further, the SC pile 1a of the first embodiment described above has a higher bending strength and shearing strength than a pile made of only concrete, for example, a prestressed concrete pile by having an outer shell steel pipe 7, but is made of metal. By suppressing the peeling suppression wall 3a from peeling a part of the pile main body 5 from the inner peripheral surface 13 of the pile main body 5, the bending strength and the shear strength can be further improved.

Preferably, the peeling suppression wall 3a is elastically in contact with the deformation of the inner peripheral surface 13 of the pile body 5 so as to urge the pile body 5 toward the outside in the radial direction.
In this way, when the peeling suppression wall 3a is elastically in contact with the inner peripheral surface 13 of the pile body 5 so as to urge the pile body 5 outward in the radial direction, the pile body 5 is in contact with the inner peripheral surface 13 of the pile body 5. Even when deformed, it is possible to prevent a gap from being formed between the inner peripheral surface 13 of the pile body 5 and the peeling suppression wall 3a. As a result, the peeling suppression wall 3a can surely prevent a part of the pile main body 5 from peeling off, and the bending strength and the shearing strength can be improved as compared with the conventional case.
The peeling suppression wall 3a is in a free state so that the peeling suppression wall 3a elastically contacts the inner peripheral surface of the pile body 5, that is, when the peeling suppression wall 3a is taken out from the pile body 5, the pile body It has a diameter or radius of curvature larger than the diameter or radius of curvature of the inner peripheral surface 13 of the portion 5.

[Second Embodiment]
FIG. 4 is a vertical cross-sectional view schematically showing the configuration of the SC pile 1b according to the second embodiment of the present invention. FIG. 5 is a schematic cross-sectional view taken along the line VV in FIG.
In the second and subsequent embodiments, configurations different from those of the preceding embodiments will be mainly described, and configurations having the same or similar shapes or functions as those described in the preceding embodiments are shown in the drawings. The same reference numerals are given to omit or simplify the description.
In the SC pile 1b, the peeling suppression wall 3b is used instead of the peeling suppression wall 3a. The peeling suppression wall 3b is located at a position different from that of the first portion 15 in the axial direction of the pile body portion 5 and has a first portion 15 and a second portion 17 that is thicker than the first portion 15. It is different from the wall 3a.

According to the SC pile 1b described above, by arranging the second portion 17 thicker than the first portion 15 in the region where a larger bending moment or shearing force is applied, in the region where a larger bending moment or shearing force is applied. It is possible to prevent a part of the pile main body 5 from peeling off. As a result, according to the SC pile 1b, the bending strength and the shearing strength can be improved as compared with the conventional case.

[Third Embodiment]
6 and 7 are perspective views schematically showing the peeling suppression wall 3c that can be used in place of the peeling suppression walls 3a and 3b. As shown in FIGS. 6 and 7, the exfoliation suppression wall 3c is different from the exfoliation suppression walls 3a and 3b in that it is composed of a spirally extending metal plate.
The peeling suppression wall 3c in FIG. 7 shows a state of being extended in the axial direction of the spiral, and has a gap 19 extending in a spiral shape. On the other hand, the peeling suppression wall 3c of FIG. 6 shows a state of being contracted in the axial direction of the spiral, and does not have the spiral gap 19 as shown in FIG. 7.
With the peeling suppression wall 3c in the state shown in FIG. 6, the inner peripheral surface 13 of the pile body 5 can be covered without a gap.
In the present embodiment, the exfoliation suppression wall 3c has a shape extending in a spiral shape, but the shape is not limited to this, and a ring shape may be used.

[Fourth Embodiment]
FIG. 8 is a schematic cross-sectional view of the SC pile 1c according to the fourth embodiment, and the inside of the circle in the figure is shown schematically by enlarging a part.
The SC pile 1c is different from the SC pile 1a in that it further has a diameter reduction suppressing portion 21 that suppresses the radius of curvature of the peeling suppressing wall 3a from becoming smaller.

When a bending moment or shearing force acts on an SC pile that does not have the diameter reduction suppressing portion 21, a force acts from the pile main body 5 to reduce the radius of curvature of the peeling suppressing wall 3a. If the pile is reduced, a gap is created between the inner peripheral surface 13 of the pile main body 5 and the peeling suppression wall 3a. On the other hand, according to the SC pile 1c having the diameter reduction suppressing portion 21, the reduction of the radius of curvature of the peeling suppressing wall 3a is suppressed, so that there is a gap between the inner peripheral surface 13 of the pile main body 5 and the peeling suppressing wall 3a. Is suppressed. As a result, the peeling suppression wall 3a can prevent a part of the pile main body 5 from peeling off, and the bending strength and the shearing strength can be improved as compared with the conventional case.

As shown in FIG. 8, the peeling suppression wall 3a is provided on the one end side end portion in the circumferential direction of the pile main body portion 5 and extends in the axial direction, and the pile main body portion 5 It has a second side edge portion 25 which is provided at the other end side end portion in the circumferential direction and extends in the axial direction and overlaps with the first side edge portion 23. The diameter reduction suppressing portion 21 projects from the first side edge portion 23 inward in the radial direction of the pile body portion, and the protrusion 27 that can come into contact with the edge of the second side edge portion 25 in the circumferential direction of the pile body portion 5. Has. The protrusion 27 is fixed to the first side edge portion 23.
According to the above configuration, since the first side edge portion 23 and the second side edge portion 25 overlap each other, the inner peripheral surface 13 of the pile main body portion 5 can be covered without a gap by the peeling suppression wall 3a.
Further, according to the above configuration, the edge of the second side edge portion 25 comes into contact with the protrusion 27 in the circumferential direction of the pile body portion 5, so that the radius of curvature of the peeling suppression wall 3a can be determined by a simple configuration. Shrinkage can be suppressed.
In the region where the first side edge portion 23 and the second side edge portion 25 overlap each other in the radial direction of the pile body portion 5, the second side edge portion 25 is inside the first side edge portion 23. positioned.

Preferably, as shown in FIG. 8, the protrusion 27 has an L-shaped cross section in the cross section of the pile body portion 5 and forms a recess that can accept the edge of the second side edge portion 25. are doing.
According to the above configuration, when the edge of the second side edge portion 25 is received in the recess and the radius of curvature of the peeling suppression wall 3a is to be reduced, the edge of the second side edge portion 25 is projected. Be sure to contact. Therefore, the reduction of the radius of curvature of the peeling suppression wall 3a can be reliably suppressed.

[Fifth Embodiment]
FIG. 9 is a schematic cross-sectional view of the SC pile 1d according to the fifth embodiment, and the inside of the circle in the figure is shown schematically by enlarging a part.
The SC pile 1d is different from the SC pile 1c in the configuration of the diameter reduction suppressing portion 21. The diameter reduction suppressing portion 21 of the SC pile 1d has at least one first engaging portion 29 and at least one second engaging portion 31.
The first engaging portion 29 is fixed to the first side edge portion 23 and projects from the first side edge portion 23 inward in the radial direction of the pile body portion 5.
The second engaging portion 31 is fixed to the second side edge portion 25 and projects from the second side edge portion 25 toward the outside of the pile body portion 5 in the radial direction.

Each of the first engaging portion 29 and the second engaging portion 31 has contact surfaces 33, 35 and sliding surfaces 37, 39.
The contact surfaces 33 and 35 come into contact with each other when the second side edge portion 25 is about to be displaced relative to the first side edge portion 23 so that the radius of curvature of the peeling suppression wall 3a becomes smaller, and the contact surfaces 33 and 35 come into contact with each other. Limits the relative displacement of the second side edge 25 with respect to the edge 23.
The sliding surfaces 37 and 39 slide with each other when the second side edge portion 25 is about to be displaced relative to the first side edge portion 23 so that the radius of curvature of the exfoliation suppressing wall 3a becomes large, and the first Allows the relative displacement of the second side edge 25 with respect to the side edge 23.

According to the above configuration, when the second side edge portion 25 tries to be displaced relative to the first side edge portion 23 so that the radius of curvature of the peeling suppression wall 3a becomes smaller, the first engaging portion 29 and the second engaging portion 29 and the second Since the contact surfaces 33 and 35 of the engaging portion 31 are in contact with each other, it is possible to suppress the reduction of the radius of curvature of the peeling suppressing wall 3a with a simple configuration.
On the other hand, when the second side edge portion 25 tries to be displaced relative to the first side edge portion 23 so that the radius of curvature of the peeling suppression wall 3a becomes large, the first engaging portion 29 and the second engaging portion 31 By sliding the sliding surfaces 37 and 39 of the above, the radius of curvature of the exfoliation suppressing wall 3a is allowed to increase. As a result, the peeling suppression wall 3a can be brought into contact with the inner peripheral surface 13 of the pile main body 5 with a simple configuration.

Preferably, as shown in FIG. 9, at least one first engaging portion 29 includes a plurality of first engaging portions 29 arranged in the circumferential direction of the pile body portion 5, and at least one second engaging portion 29. The joint portion 31 includes a plurality of second engaging portions 31 arranged in the circumferential direction of the pile main body portion 5.
According to the above configuration, a plurality of first engaging portions 29 and a plurality of second engaging portions 31 arranged in the circumferential direction of the pile main body portion 5 are provided, and the plurality of first engaging portions 29 and the plurality of first engaging portions 29 are provided. The contact surfaces 33 and 35 of the first engaging portion 29 and the second engaging portion 31 appropriately selected among the second engaging portions 31 of the above are brought into contact with each other, thereby causing the inner circumference of the pile body portion 5 to come into contact with each other. The peeling suppression wall 3a can be brought into contact with the surface without a gap.

Preferably, as shown in FIG. 9, the first engaging portion 29 and the second engaging portion 31 have a right-angled triangular cross-sectional shape when viewed in cross section of the pile body portion 5.
According to the above configuration, the first engaging portion 29 and the second engaging portion 31 have a cross-sectional shape of a right triangle, and the reduction of the radius of curvature of the peeling suppressing wall 3a is suppressed by a simple configuration. be able to.

[Sixth Embodiment]
FIG. 10 is a schematic cross-sectional view of the SC pile 1e according to the sixth embodiment, and the inside of the circle in the figure is shown schematically by enlarging a part.
The SC pile 1e is different from the SC pile 1c in the configuration of the diameter reduction suppressing portion 21. The diameter reduction suppressing portion 21 of the SC pile 1e includes a first fixing base 41, a second fixing base 43, a bolt 45, and a diameter reduction suppressing nut 46.
The first fixing base 41 is fixed to the first side edge portion 23 and projects inward from the first side edge portion 23 in the radial direction of the pile body portion 5.
The second fixing base 43 is fixed to the second side edge portion 25 and projects inward from the second side edge portion 25 in the radial direction of the pile body portion 5.

The bolt 45 extends between the first fixing base 41 and the second fixing base 43.
The diameter reduction suppressing nut 46 is screwed into the bolt 45 and limits the reduction of the distance between the first fixing base 41 and the second fixing base 43.

According to the above configuration, the bolt 45 and the diameter reduction suppressing nut 46 are used to limit the reduction of the distance between the first fixing base 41 and the second fixing base 43, thereby peeling off with a simple configuration. It is possible to suppress the reduction of the radius of curvature of the restraining wall 3a.
Preferably, as shown in FIG. 10, bolt holes 47 and 48 through which the bolts 45 are inserted are formed in the first fixing base 41 and the second fixing base 43, respectively, and the bolt holes 47 and 48 are the first. It has a shape that allows an angle change of the bolt 45 with respect to the fixing base 41 and the second fixing base 43, for example, an elongated hole shape.
The first fixing base 41 and the second fixing base 43 may be formed with slits through which the bolts 45 can be inserted instead of the bolt holes 47 and 48.

[7th Embodiment]
FIG. 11 is a schematic cross-sectional view of the SC pile 1f according to the seventh embodiment, and the inside of the circle in the figure is shown schematically by enlarging a part. FIG. 12 is a schematic cross-sectional view taken along the line XII-XII in FIG. FIG. 13 is a perspective view schematically showing the diameter reduction suppressing portion 21 used for the SC pile 1f.
The SC pile 1f is different from the SC pile 1c in the configuration of the diameter reduction suppressing portion 21. As shown in FIGS. 11 to 13, the diameter reduction suppressing portion 21 of the SC pile 1f is composed of a spiral member 49. The spiral member 49 has a spiral shape extending so as to swivel around the axis of the pile body 5, and is arranged inside the peel suppression wall 3a in the radial direction of the pile body 5 so as to be in contact with the peel suppression wall 3a. Has been done. For example, the spiral member 49 is formed by bending a metal wire rod in a spiral shape.
According to the above configuration, the spiral member 49 having a spiral shape can suppress the reduction of the radius of curvature of the peeling suppression wall 3a with a simple configuration.
Preferably, the spiral pitch P (distance between centers) of the spiral member 49 is 50 mm or more and 300 mm or less.

[8th Embodiment]
FIG. 14 is a perspective view schematically showing a hollow spiral member 51 as a modification of the spiral member 49 of FIG. 13. The spiral member 51 is a tube made of resin or rubber, and is bent in a spiral shape. The inside of the spiral member 51 is filled with atmospheric pressure, preferably a liquid having a pressure higher than atmospheric pressure, such as water or oil. The tube may contain reinforcing fibers.
According to the above configuration, the rigidity of the spiral member 51 can be increased by filling the spiral member 51 with a liquid. Therefore, the spiral member 51 can suppress the reduction of the radius of curvature of the peeling suppressing wall 3a with a simple structure.
The inside of the spiral member 51 may be filled with a curable material such as cement, mortar or grout instead of the liquid. Alternatively, a metal wire, for example, a piano wire may be inserted into the spiral member 51 instead of the liquid. Alternatively, the inside of the spiral member 51 may be filled with fibers or the like.

Preferably, as shown in FIG. 15, a pitch determining member 53 that determines the spiral pitch P of the spiral member 51 is used together with the spiral member 51. The pitch determining member 53 has an extending portion 55 extending in the axial direction of the pile main body portion 5 and a plurality of annular portions 57 provided integrally with the extending portion 55. The plurality of annular portions 57 are provided at equal intervals in the axial direction of the pile main body portion 5. For example, the extending portion 55 and the annular portion 57 are composed of a fiber band.
According to the above configuration, by inserting the spiral member 51 through the plurality of annular portions 57, it is possible to prevent the pitch P of the spiral member 51 from becoming excessive, and the spiral member 51 reduces the radius of curvature of the peeling suppression wall 3a. Can be reliably suppressed.
In FIG. 15, the two pitch determining members 53 are arranged so as to be separated from each other in the diameter direction of the pile body 5, but the number of pitch determining members 53 is not limited to two. There may be one or three or more.
Further, in the present embodiment, the case where the spiral members 49 and 51 having a spiral shape are used has been described, but the present invention is not limited to the spiral shape, and a ring-shaped member may be used.

[9th Embodiment]
FIG. 16 is a schematic vertical sectional view of 1 g of SC pile according to the ninth embodiment. The SC pile 1g is different from the SC pile 1c in the configuration of the diameter reduction suppressing portion 21. As shown in FIG. 16, the diameter reduction suppressing portion 21 of the SC pile 1g is composed of a bag 59 arranged inside the peeling suppressing wall 3a in the radial direction of the pile main body portion 5. The bag 59 is made of a non-stretchable and waterproof material, such as a waterproof cloth. A water supply port 60 that can be closed is attached to the bag 59, and the bag 59 can be filled with a liquid, preferably water, and sealed through the water supply port 60.
The bag 59 is filled with a liquid at atmospheric pressure, preferably at a pressure higher than atmospheric pressure, and the bag 59 can reliably suppress the reduction of the radius of curvature of the exfoliation suppressing wall 3a with a simple configuration. it can.
When the bag 59 is made of a non-stretchable material, the bag 59 before filling with the liquid has slack so that the volume can be expanded by filling with the liquid.

[10th Embodiment]
FIG. 17 is a schematic vertical sectional view of the SC pile 1h according to the tenth embodiment. The SC pile 1h is different from the SC pile 1g in that it has a partition member 61 and a communication pipe 62.
The partition member 61 is provided on one end side of the SC pile 1h so as to cover the opening of the hollow portion 11. The partition member 61 is made of metal, for example, and is fixed to the end plate 9 by welding.
The communication pipe 62 penetrates the partition member 61 and extends over the entire length of the SC pile 1h in the axial direction of the pile body 5.
The bag 59 filled with water is arranged on the outer side in the radial direction of the communication pipe 62, and can come into contact with the peeling prevention wall 3a while surrounding the communication pipe 62.

According to the SC pile 1h described above, when the SC pile 1h is submerged from the partition member 61 side into the pile hole in which the soil cement is accumulated, the partition member 61 prevents the soil cement from flowing into the hollow portion 11. , Soil cement can be flowed upward through the communication pipe 62. Therefore, it is possible to prevent the hollow portion 11 from being filled with the soil cement, and the bag 59 filled with water can be brought into contact with the peeling prevention wall 3a.

[11th Embodiment]
FIG. 18 is a cross-sectional view schematically showing a bag 63 that can be connected to each other as a modification of the bag 59 of FIG.
FIG. 18 shows two bags 63 connected to each other. The bag 63 is provided with a connecting means for connecting the bags 63 to each other. The connecting means can connect the plurality of bags 63 while communicating the insides of the plurality of bags 63 with each other.
Specifically, the connecting means includes a first connecting portion 67 and a second connecting portion 69.
The bag 63 has an opening to which the first connecting portion 67 and the second connecting portion 69 are attached, and is made of, for example, a non-stretchable waterproof material.
The first connecting portion 67 has a hollow cylindrical cylindrical portion 71, a flange portion 73 integrally provided on one end side of the cylindrical portion 71, and a male screw portion 75 provided on the outer peripheral surface of the cylindrical portion 71. The opening edge of the bag 63 is liquid-tightly attached to the collar portion 73, and the cylindrical portion 71 extends outward from the bag 63.

The second connecting portion 69 includes a hollow cylindrical cylindrical portion 77 having an inner diameter larger than the outer diameter of the cylindrical portion 71 of the first connecting portion 67, and a flange portion 79 integrally provided on one end side of the cylindrical portion 77. , Has a female screw portion 81 provided on the inner peripheral surface of the cylindrical portion 77. The opening edge of the bag 63 is liquid-tightly attached to the collar portion 79, and the cylindrical portion 77 extends toward the inside of the bag 63.
The female threaded portion 81 of the second connecting portion 69 is formed so as to be screwable with the male threaded portion 75 of the first connecting portion 67, and when connecting the two bags 63, the second connecting portion 69 of the one bag 63 The male threaded portion 75 of the first connecting portion 67 of the other bag 63 may be screwed into the female threaded portion 81.

According to the above configuration, by connecting the plurality of bags 63, the bags 63 can be arranged inside the peeling suppression wall 3a by the required length in the axial direction of the pile main body 5.
Moreover, according to the above configuration, the cylindrical portion 71 of the first connecting portion 67 extends outward from the bag 63, and the cylindrical portion 77 of the second connecting portion 69 extends toward the inside of the bag 63. When the male threaded portion 75 and the female threaded portion 81 of the second connecting portion 69 are screwed together, the gap between the flange portion 73 of the first connecting portion 67 and the flange portion 79 of the second connecting portion 69 can be reduced. .. That is, when the two bags 63 are connected, the gap between the two bags 63 can be reduced. Therefore, even when a plurality of bags 63 are used, the reduction of the radius of curvature of the peeling suppression wall 3a can be reliably suppressed.

Preferably, each bag 63 has a first connecting portion 67 and a second connecting portion 69. In this case, when the SC pile is installed in the pile hole, which of the first connecting portion 67 and the second connecting portion 69 may be located above in each bag 63. Of the first connecting portion 67 and the second connecting portion 69, the one located at the uppermost position can be used as the water supply port 60. The uppermost of the first connecting portion 67 and the second connecting portion 69 is closed by the lid 85. On the other hand, of the first connecting portion 67 and the second connecting portion 69, the one located at the lowermost position is closed by the plug 83.

Preferably, the first connecting portion 67 or the second connecting portion 69 is provided with a check valve 87. The check valve 87 is arranged so as to allow the flow of water into the bag 63 and prohibit the flow of water from the bag 63 to the outside.
According to the above configuration, after filling the bag 63 with high-pressure water through the water supply port 60, the lid 85 can be easily attached without reducing the pressure in the bag 63.

[12th Embodiment]
FIG. 19 is a schematic vertical sectional view of the SC pile 1i according to the twelfth embodiment. The SC pile 1i is different from the SC pile 1h in that it has a bag 89 made of a stretchable material such as rubber instead of the bag 59, and further has a pressing member 91.
The pressing member 91 is located on the opposite side of the partition member 61, and at least partially covers the opening of the hollow portion 11 on the other end side of the SC pile 1h. The pressing member 91 is made of metal, for example, and is fixed to the end plate 9. The communication pipe 62 penetrates the partition member 61 and the pressing member 91.
According to the above configuration, even if the bag 89 is made of a stretchable material, the partition member 61 and the pressing member 91 prevent the bag 89 from expanding to the outside of the SC pile 1i.

[13th Embodiment]
FIG. 20 is a schematic vertical sectional view of the SC pile 1j according to the twelfth embodiment. The SC pile 1j has a communication pipe 62 penetrating the center of the hollow portion 11 in the radial direction of the pile main body portion 5, and a stretchable or non-stretchable bag body 93 having a hole 95 through which the communication pipe 62 is inserted. In that respect, it differs from the SC pile 1h. The bag body 93 can be expanded into a tube shape by injecting a liquid.
According to the above configuration, since the communication pipe 62 is arranged in the center, the bag body 93 is attached to the peeling suppression wall 3a over the entire circumferential direction of the pile main body portion 5 without being hindered by the communication pipe 62. Can be contacted.

[14th Embodiment]
FIG. 21 is a partial cross-sectional view showing a part of the cross section of the SC pile 1k according to the 14th embodiment. As shown in FIG. 21, the SC pile 1k is different from the SC pile 1e shown in FIG. 10 in that it has a reduced diameter portion 97.
The reduced diameter portion 97 can reduce the radius of curvature of the exfoliation suppressing wall 3a.
According to the SC pile 1k described above, the radius of curvature of the peeling suppression wall 3a can be reduced by the diameter reduction portion 97, and the peeling suppression wall 3a can be easily arranged in the hollow portion 11 of the pile body portion 5. ..

Preferably, the reduced diameter portion 97 includes a first fixing base 41 fixed to the first side edge portion 23, a second fixing base 43 fixed to the second side edge portion 25, and a first fixing base 41 and a second. 2 A bolt 45 extending between the fixing base 43 and a reduced diameter nut 99 screwed into the bolt 45 and capable of reducing the distance between the first fixing base 41 and the second fixing base 43 together with the bolt 45. , Have.
According to the above configuration, the bolt 45 and the reduced diameter nut 99 are used to reduce the distance between the first fixing base 41 and the second fixing base 43, thereby suppressing peeling with a simple configuration. The radius of curvature of the wall 3a can be reduced. As a result, according to the above configuration, the peeling suppression wall 3a can be easily arranged in the hollow portion 11 of the pile main body portion.

Further, according to the above configuration, the diameter reduction suppressing portion 21 can be provided with a simple configuration only by adding the diameter reduction suppressing nut 46.

[15th Embodiment]
FIG. 22 is a schematic vertical sectional view of a prestressed concrete pile (hereinafter, also referred to as a PC pile) 1 m according to the fifteenth embodiment. The PC pile 1m is different from the SC pile 1a in that it does not have the outer shell steel pipe 7 and has a plurality of PC steel rods 101 provided between the end plates 9 and 9.
Even in the PC pile 1 m, the metal peeling suppression wall 3a is arranged in the hollow portion 11 of the pile main body 5 and is in contact with the inner peripheral surface 13 of the pile main body 5. Therefore, when a bending moment or a shearing force acts on the pile main body 5 to deform the pile main body 5, it is possible to prevent a part of the pile main body 5 from peeling off from the inner peripheral surface 13 of the pile main body 5. Will be done. As a result, according to the PC pile 1 m, the bending strength and the shearing strength can be improved as compared with the conventional case.
That is, although the present invention is suitable for SC piles, a cylindrical pile body portion containing concrete and having a hollow portion such as a PC pile, a high-strength prestressed concrete pile (PHC pile), and a reinforced concrete pile (RC pile) is provided. It can be applied to all ready-made concrete piles that have.

[16th Embodiment]
FIG. 23 is a flowchart showing a schematic procedure of a method for manufacturing a concrete pile according to an embodiment of the present invention. The concrete pile manufacturing method shown in FIG. 23 can be used for manufacturing the SC piles 1a to 1k and the PC pile 1m described above.
The method for manufacturing a concrete pile includes a pile body preparation step S1, a peeling suppression wall preparation step S2, a diameter reduction step S3, a restraint step S4, an insertion step S5, and a diameter expansion step S6.
In the pile body portion preparation step S1, a cylindrical pile body portion 5 including concrete and having a hollow portion 11 is prepared.
In the peeling suppression wall preparation step S2, a metal peeling suppression wall 3a having a first side edge portion 23 and a second side edge portion 25 is prepared.
In the diameter reduction step S3, the radius of curvature is reduced until the peeling suppression wall 3a can be inserted into the hollow portion 11 so that the first side edge portion 23 and the second side edge portion 25 overlap each other (hereinafter, this state). Is called the reduced state). In the reduced state, the radius of curvature of the peeling suppression wall 3a is smaller than the radius of curvature of the inner peripheral surface 13 of the pile body 5.
In the restraint step S4, the peeling suppression wall 3a is restrained so that the peeling suppression wall 3a curved in the diameter reduction step S3 maintains the reduced state.
In the insertion step S5, after the restraint step S4, the peeling suppression wall 3a in the reduced state is inserted into the pile body 5.
In the diameter expansion step S6, after the insertion step S5, the restraint of the peeling suppression wall 3a is released, and the peeling suppression wall 3a is brought into contact with the inner peripheral surface of the pile body 5.

According to the above configuration, the peeling suppression wall 3a is restrained in a reduced state and inserted into the hollow portion 11 of the pile body portion 5, and the restraint is released so that the wall 3a is curved so as to be in contact with the inner peripheral surface 13 of the pile body portion 5. The peeling suppression wall 3a can be easily arranged in the hollow portion 11 of the pile main body portion 5.
Then, in the concrete pile manufactured by the method for manufacturing a concrete pile having the above configuration, when the pile main body 5 is deformed by the bending moment or the shearing force, the pile main body is formed from the inner peripheral surface 13 of the pile main body 5. Part of 5 is suppressed from peeling off. As a result, the bending strength and shearing strength of the concrete pile can be improved as compared with the conventional case.

Preferably, in the restraining step S4, both ends of the peeling suppressing wall 3a in the reduced state are restrained by the restraining means, and in the inserting step S5, the peeling suppressing wall restrained by the restraining means is restrained by the pile body portion. It is inserted into the hollow portion, and the restraint of the peeling suppressing wall 3a by the restraining means is released in the diameter expanding step S6.
According to the above configuration, both ends of the peeling suppression wall 3a are restrained by restraining means, and the restrained peeling suppressing wall 3a is inserted into the hollow portion 11 of the pile body portion 5, so that the peeling suppressing wall 3a can be easily inserted. be able to. Further, in the diameter expanding step S6, the peeling suppressing wall 3a can be easily brought into contact with the inner peripheral surface 13 of the pile main body 5 by releasing the restraint by the restraining means.

As the restraining means, the reduced diameter portion 97 shown in FIG. 21 can be used. In this case, if the diameter reduction nut 99 is rotated in the diameter reduction step S3 to bend the peeling suppression wall 3a, the restraint step S4 is also completed at the same time as the diameter reduction step S3 is completed, and the peeling suppression wall 3a is completed by the diameter reduction nut 99. Can be restrained. Then, by rotating the diameter reduction nut 99 in the opposite direction in the diameter expansion step S6, the peeling suppression wall 3a can be easily brought into contact with the inner peripheral surface 13 of the pile body 5.

FIG. 24 is a diagram schematically showing a lever block (registered trademark) 103 together with a cross section of a concrete pile as a restraining means used in the restraining step S4. In FIG. 24, two engaging portions 105 are fixed to the inner surface of the peeling suppression wall 3a, and the hooks of the lever block (registered trademark) 103 are engaged with the engaging portions 105 and 105.
In this case, the radius of curvature of the peeling suppression wall 3a can be easily reduced and restrained by operating the lever block (registered trademark) 103 to bring the engaging portions 105 and 105 closer to each other. Then, in the diameter expansion step S6, the lever block (registered trademark) 103 is operated to move the engaging portions 105 and 105 away from each other, so that the peeling suppression wall 3a easily contacts the inner peripheral surface 13 of the pile body portion 5. Can be made to.

FIG. 25 is a partial cross-sectional view schematically showing a part of a cross section of a concrete pile, and is a diagram for explaining a case where welding is used as a restraining means used in the restraining step S4. In FIG. 25, the first side edge portion 23 and the second side edge portion 25 of the peeling suppression wall 3a are fixed to each other by the welded portion 107, and the peeling suppressing wall 3a is formed by the welded portion 107 as a restraining means. It can be easily restrained. Then, in the diameter expanding step S6, by removing the welded portion 107 with a grinder or the like, the peeling suppressing wall 3a can be easily brought into contact with the inner peripheral surface 13 of the pile main body portion 5.

FIG. 26 is a perspective view schematically showing a peeling suppression wall 3a restrained by a lashing belt 109 as a restraining means.
The lashing belt 109 restrains the peeling suppression wall 3a in a state of surrounding the curved peeling suppression wall 3a from the outside. When the peeling suppression wall 3a is restrained from the outside as in the case of using the lashing belt 109, it is preferable to prepare the peeling suppression wall 3a in advance so as to be longer than the pile main body 5. In this case, in the insertion step S5, the peeling suppression wall 3a is provided on the pile body 5 so that both ends of the peeling suppression wall 3a restrained by the restraining means such as the lashing belt 109 extend from both ends of the pile body 5. insert. Then, after releasing the restraint in the diameter expanding step S6, both ends of the peeling suppression wall 3a extending from the pile main body 5 may be cut and removed.

FIG. 27 is a perspective view schematically showing a cap 111 as a restraining means together with a peeling suppression wall 3a curved in a reduced state by a lashing belt 109.
The cap 111 has a cylindrical shape and is made of, for example, metal. The peeling suppression wall 3a can be restrained by fitting the cap 111 to both ends of the peeling suppression wall 3a in the reduced state. In this case, the lashing belt 109 as a bending means for bending the peeling suppression wall 3a may be removed after the cap 111 is attached to the peeling suppression wall 3a. Then, in the insertion step S5, the peeling suppression wall 3a restrained by the cap 111 is inserted into the hollow portion 11 of the pile body portion 5.
When the cap 111 is used, if the cap 111 can be removed, it is not necessary to prepare the peeling suppression wall 3a so as to be longer than the pile main body 5.
A lever block (registered trademark) can be used in addition to the lashing belt 109 as a restraining means that can bend and restrain the peeling suppressing wall 3a from the outside. Further, as a restraining means capable of restraining the peeling suppressing wall 3a from the outside, a wire, a chain or the like can be used in addition to the cap 111.
Finally, the present invention is not limited to the above-described embodiment, and includes a modification of the above-described embodiment and a combination of these embodiments as appropriate.

1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k Concrete pile with outer shell steel pipe (SC pile)
1m prestressed concrete pile (PC pile)
3a, 3b, 3c Peeling suppression wall 5 Pile body 7 Outer shell steel pipe 9 End plate 11 Hollow part 13 Inner peripheral surface 15 1st part 17 2nd part 19 Gap 21 Shrinkage suppression part 23 1st side edge 25 2nd Side edge 27 Protrusion 29 1st engaging 31 2nd engaging 33, 35 Contact surface 37, 39 Sliding surface 41 1st fixing base 43 2nd fixing base 45 Bolt 46 Shrinkage suppression nut 47, 48 bolt Hole 49, 51 Spiral member 53 Pitch determination member 55 Extending part 57 Circular part 59, 63, 89 Bag 60 Water supply port 61 Partition member 62 Communication pipe 67 First connecting part 69 Second connecting part 71 Cylindrical part 73 Collar part 75 Male screw Part 77 Cylindrical part 79 Flange part 81 Female thread part 83 Plug 85 Lid 87 Check valve 91 Holding member 93 Bag body 95 Hole 97 Reduced diameter part 99 Reduced diameter nut 101 PC steel rod 103 Lever block (registered trademark)
105 Engagement 107 Welding 109 Lashing belt 111 Cap

Claims (16)

A cylindrical pile body that contains concrete and has a hollow part,
A metal exfoliation suppression wall arranged in the hollow portion of the pile main body and curved along the inner peripheral surface so as to be in contact with the inner peripheral surface of the pile main body.
Equipped with a,
The exfoliation suppressing wall has a substantially cylindrical shape, has an outer diameter larger than the inner diameter of the inner peripheral surface of the pile main body in the free state, and has a diameter reduced in the pile main body from the free state. A concrete pile characterized in that it is elastically in contact with the inner peripheral surface of the pile body so as to urge the pile body in the radial direction . The concrete pile according to claim 1, further comprising an outer shell steel pipe that covers the outer peripheral surface of the pile main body. The claim is characterized in that the peeling suppression wall has a first portion and a second portion which is located at a position different from the first portion in the axial direction of the pile main body portion and is thicker than the first portion. The concrete pile according to 1 or 2 . The concrete pile according to any one of claims 1 to 3 , further comprising a diameter reduction suppressing portion capable of suppressing reduction of the radius of curvature of the peeling suppressing wall. The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion projects from the first side edge portion inward in the radial direction of the pile body portion, and is a protrusion capable of contacting the edge of the second side edge portion in the circumferential direction of the pile body portion. The concrete pile according to claim 4 , wherein the concrete pile has. The protrusions claim 5, wherein the sectional shape of the L-shaped in cross-section of the pile body portion to form a recess capable of receiving an edge of the second side edge portion The concrete pile described in. The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
At least one first engaging portion protruding from the first side edge portion inward in the radial direction of the pile body portion,
With at least one second engaging portion protruding from the second side edge portion toward the radial outer side of the pile body portion,
Have,
The first engaging portion and the second engaging portion are
When the second side edge portion is about to be displaced relative to the first side edge portion so as to reduce the radius of curvature of the exfoliation suppressing wall, the second side edge portion comes into contact with each other and the second side with respect to the first side edge portion. A contact surface that limits the relative displacement of the edges,
When the second side edge portion is about to be displaced relative to the first side edge portion so as to increase the radius of curvature of the exfoliation suppressing wall, the second side edge portion slides with each other and the second side edge portion with respect to the first side edge portion. A sliding surface that allows relative displacement of the side edges,
The concrete pile according to claim 4 , wherein the concrete pile has. The at least one first engaging portion includes a plurality of first engaging portions arranged in the circumferential direction of the pile body portion.
The concrete pile according to claim 7 , wherein the at least one second engaging portion includes a plurality of second engaging portions arranged in the circumferential direction of the pile main body portion. The concrete pile according to claim 8 , wherein the first engaging portion and the second engaging portion have a cross-sectional shape of a right triangle when viewed in cross section of the pile main body portion. The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
The first fixing base fixed to the first side edge portion and
A second fixing base fixed to the second side edge,
A bolt extending between the first fixing base and the second fixing base,
The concrete pile according to claim 4 , wherein the concrete pile is screwed onto the bolt and has a diameter reduction suppressing nut that limits the reduction of the distance between the first fixing base and the second fixing base. The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is arranged inside the peeling suppressing wall in the radial direction of the pile body portion so as to be in contact with the peeling suppressing wall, and is composed of a spiral member having a spiral shape. The concrete pile according to claim 4 . The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The diameter reduction suppressing portion is
A bag arranged inside the peeling prevention wall in the radial direction of the pile body, and
With the water filled in the bag,
The concrete pile according to claim 4 , wherein the concrete pile has. The concrete pile according to any one of claims 1 to 12 , further comprising a reduced diameter portion capable of reducing the radius of curvature of the exfoliation suppressing wall. The exfoliation suppression wall
A first side edge portion provided at one end side end portion in the circumferential direction of the pile body portion and extended in the axial direction, and a first side edge portion.
It has a second side edge portion that is provided at the other end side end portion in the circumferential direction of the pile body portion, extends in the axial direction, and overlaps with the first side edge portion.
The reduced diameter portion is
The first fixing base fixed to the first side edge portion and
A second fixing base fixed to the second side edge,
A bolt extending between the first fixing base and the second fixing base,
A reduced diameter nut screwed into the bolt and capable of reducing the distance between the first fixing base and the second fixing base together with the bolt.
The concrete pile according to claim 13 , wherein the concrete pile has. A pile body preparation process that prepares a cylindrical pile body that includes concrete and has a hollow part,
A metal substantially cylindrical peeling suppression wall having a first side edge portion and a second side edge portion , which has an outer diameter larger than the inner diameter of the inner peripheral surface of the pile body portion in a free state. The process of preparing the peeling prevention wall and
A diameter reduction step of bending the exfoliation suppressing wall to a reduced state that can be inserted into the hollow portion so that the first side edge portion and the second side edge portion overlap each other.
A restraining step of restraining the peeling suppressing wall so that the peeling suppressing wall maintains the reduced state, and
After the restraint step, an insertion step of inserting the peeling suppression wall in the reduced state into the pile body portion, and
After the insertion step, the restraint of the peeling suppression wall is released, and the peeling suppression wall is urged toward the radial outer side of the pile main body in a state where the diameter is reduced from the free state. The diameter expansion process that elastically contacts the inner peripheral surface of the main body,
A method for manufacturing a concrete pile, which comprises. In the restraining step, both ends of the peeling suppression wall are restrained by the restraining means in the reduced state.
In the insertion step, the peeling suppression wall restrained by the restraining means is inserted into the hollow portion of the pile body portion.
The method for manufacturing a concrete pile according to claim 15 , wherein in the diameter-expanding step, the restraint of the exfoliation suppressing wall by the restraining means is released.

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