JP2018119385A - Sc pile having axial reinforcement, method for manufacturing sc pile having axial reinforcement, and method for exposing axial reinforcement of sc pile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate handling at the time of conveyance and construction and to facilitate exposure of axial reinforcement 10 after the construction.SOLUTION: There is provided an SC pile in which a reinforcement cage 60 is embedded in a concrete part 64 on the outer peripheral side of a steel pipe 1. In the reinforcement cage 60, a shape of annularly arranged axial reinforcement 10 is retained by an upper end plate 20, a partition plate 30 and a guide plate 40, and the upper end plate 20 and the partition plate 30 are connected to each other with a PC steel bar 50. The arranged axial reinforcement 10 is covered with a coated pipe 16 arranged between the upper end plate 20 and the partition plate 30, and the upper end 11 is made to positioned in a first reinforcement insertion hole 24 of the upper end plate 20 and is detachably and temporarily fixed to the upper end plate 20 with a screw fixture 55. The axial reinforcement 10 is arranged striding over a planned cut position 7 of the steel pipe 1, and the partition plate 30 is arranged directly above the planned cut position 7 (b). An SC pile 65 is used in a state where the screw fixture 55 is removed, and the first reinforcement insertion hole 24 is exposed (a).SELECTED DRAWING: Figure 1

Description

  The present invention relates to an SC pile having an axial rebar characteristic of the structure of the reinforcing bar cage, a manufacturing method of the SC pile having an axial reinforcing bar characteristic of the assembly of the reinforcing bar cage including the axial reinforcing bar, and embedded at the time of construction. It is related with the exposure method of the axial reinforcement of SC pile which exposes an axial reinforcement from SC pile.

In general, a ready-made pile buried in the vicinity of the ground uses a concrete pile (so-called SC pile) covered with a steel pipe in order to strengthen the horizontal strength. In addition, since the ready-made pile made from concrete was manufactured by centrifugal molding in order to make concrete dense, the structure of the reinforcing steel cage which ensures shape retention property becomes important on manufacture.
In addition, when supporting a building with a foundation pile buried in the ground, when using a concrete ready-made pile as the foundation pile, the axial rebar (structural rebar) constituting the ready-made pile and the lower end of the building ( It was necessary to fix the structural reinforcement of the footing).

In this case, in one method, the axial rebar is projected upward from the upper end of the ready-made pile in advance, and after burying the ready-made pile, the rebar is connected to the upper end of the axial rebar and connected to the structural rebar of the building. (Patent Document 3).
In another method, the upper end of the axial reinforcing bar of the ready-made pile is covered with a protective cylinder to form the ready-made pile in a non-concrete state. The upper end part of concrete was pulled out with the protection cylinder material, and the upper end part of the axial direction reinforcement of a ready-made pile was exposed (patent documents 1 and 2).
Moreover, in the case of the said other method, it is necessary to fix a protection cylinder material and an axial rebar to an upper side end plate, and in the case of patent document 1 (no steel pipe in an upper end part), the outer end part of an axial rebar The threaded portion was formed on the end plate, and the threaded portion was protruded from the end plate, and a nut was screwed onto the threaded portion to fix the axial rebar to the upper end plate. In addition, in the case of Patent Document 2 (with a steel pipe at the upper end), an auxiliary plate having a protrusion is attached from the outside of the upper end plate, the protrusion is inserted into the covering cylinder member, and the axial rebar and the covering cylinder member are end It was inserted into the plate hole and fixed.

JP 2010-196251 A JP 2010-255394 A JP 2011-111848 A

In the above one method, since the axial rebar protrudes from the upper end plate of the ready-made pile, the axial rebar exposed and protruding from the end plate is obstructive at the time of manufacturing for centrifugal molding or embedment in the ground. There were problems that were difficult to handle. In other methods, the auxiliary plate protrudes from the upper end plate.
Further, when the concrete outer periphery of the upper end of the ready-made pile is cut by the above-mentioned method, the steel plate is exposed to the remaining part, so that there is a problem that it is difficult to fix with the concrete footing to be constructed thereafter. It was.

  The present invention solves the above-mentioned problems by using SC piles, with the upper end of the axial rebar positioned below the upper surface of the upper end plate and the partition plate positioned above the planned cutting position of the steel pipe.

That is, the invention of this SC pile is configured as follows in the SC pile formed by fixing the upper end plate and, if necessary, the lower end plate on the upper and lower sides of the steel pipe and forming a concrete portion having a hollow portion in the steel pipe. It is SC pile provided with the axial rebar characterized by this.
(1) The steel pipe was divided into an upper part and a lower part at a predetermined cutting position along the outer periphery at a predetermined height in the axial direction.
(2) Across the planned cutting position of the steel pipe, axial rebars are annularly arranged at the upper and lower parts, and a donut-shaped partition plate is provided above the planned cutting position in the length direction of the steel pipe. The axial rebars are penetrated through the partition plate.
(3) A fixing portion is formed at the upper end of the axial rebar, and the upper end of the axial rebar is positioned below the upper surface of the upper end plate.
(4) The fixing portion of the axial rebar is detachably attached to a fixture that is detachably attached to the upper end plate.
(5) Each of the axial rebars was covered with a reinforcing bar covering material disposed between the partition plate and the upper end plate.
(6) The upper end plate and the partition plate are connected by a plate connecting member disposed substantially parallel to the axial rebar.
(7) The upper end plate, the partition plate, the axial reinforcing bar partially covered with the reinforcing bar covering material, and the plate connecting member constitute a reinforcing bar cage, and the reinforcing bar cage is embedded in the concrete portion. It was.

Moreover, in the invention of the SC pile, the SC pile is provided with an axial rebar characterized by the following configuration.
(1) A threaded portion was formed at the upper end of the axial rebar, the first rebar insertion hole was formed in the upper end plate, and the upper end of the threaded portion was positioned within the first rebar insertion hole.
(2) A nut portion of a screw fixture locked on the upper surface side of the upper end plate was inserted into the first rebar insertion hole, and detachably screwed into the screw portion.
(3) A second rebar insertion hole was formed in the partition plate to penetrate the axial rebar.
(4) The upper end of the hollow reinforcing bar covering material was brought into contact with the upper end plate, and the lower end was brought into contact with the partition plate, so that the upper and lower sides of the covering material were substantially sealed.

Moreover, in the invention of the SC pile, the SC pile is provided with an axial rebar characterized by the following configuration.
(1) The lower surface of the partition plate was positioned directly above the planned cutting position.
(2) Below the planned cutting position, a guide plate is provided in parallel with the partition plate, and an axial rebar is passed through the guide plate, and the guide plate is placed at a predetermined position of the steel pipe on the outer periphery of the guide plate. In order to keep it at a constant value, a spacer arranged along the inner periphery of the steel pipe was attached.
(3) On the upper surface of the partition plate, a covering material locking recess was formed around the second reinforcing bar insertion hole, and the lower surface of the reinforcing bar covering material was positioned.

Further, the invention of the manufacturing method is a method of manufacturing a SC pile by placing a reinforcing steel cage provided with an axial reinforcing bar in a steel pipe having a predetermined cutting position in the axial direction, injecting concrete, and performing centrifugal molding. And it is a manufacturing method of SC pile provided with the axial direction rebar characterized by being constituted as follows.
(1) The rebar cage structure is configured as follows as follows.
(a) An upper end plate and a partition plate are juxtaposed along the axial direction, the axial rebar is passed through the partition plate, and the upper end of the axial rebar is positioned within the thickness of the upper end plate.
(b) The rebar covering material arranged between the upper end plate and the partition plate covered the axial rebar.
(c) The upper end plate and the partition plate are connected by a plate connecting member that maintains a predetermined interval.
(2) A rebar cage is inserted from the upper end side of the steel pipe, the upper end plate is welded and fixed to the upper end of the steel pipe, and the partition plate is positioned closer to the upper end side than the planned cutting position of the steel pipe.
(3) Subsequently, a fixing tool is attached from the upper surface side of the upper end plate, and the fixing portion on the upper end side of the axial rebar is detachably held.
(4) Subsequently, the concrete is poured into the steel pipe and cured, and after the concrete is solidified, the fixture is removed to form the SC pile.

Moreover, in the invention of the manufacturing method, it is a manufacturing method of an SC pile provided with an axial reinforcing bar, which is configured as follows.
(1) The rebar cage structure was constructed as follows.
(a) A first reinforcing bar insertion hole is formed in the upper end plate and a second reinforcing bar insertion hole is formed in the partition plate in accordance with the position of the axial reinforcing bar, and the axial reinforcing bar is arranged on the guide plate arranged below the partition plate. Accordingly, a rebar insertion notch opened in the radial direction was formed, and a threaded portion was formed at the tip of the axial rebar.
(b) The axial rebar is inserted into the second rebar insertion hole of the partition plate, locked to the rebar insertion notch of the guide plate, and the upper end of the screw portion of the axial rebar is connected to the upper end plate of the upper end plate. It was located in the single rebar insertion hole.
(2) Subsequently, the rebar cage is disposed in the steel pipe, the guide plate is disposed near the center in the steel pipe, and the lower end portion of the axial rebar is disposed at a predetermined position.
(3) Subsequently, a screw fixture is inserted into the first rebar insertion hole from above the upper end plate, and the screw fixture is locked to the upper surface of the upper end plate, and the screw fixture and the shaft The screw part of the directional reinforcing bar is screwed and temporarily fixed.
(4) Subsequently, the concrete is poured into the steel pipe and cured, and after the concrete is solidified, the fixture is removed to form the SC pile.

Further, the invention of the method for exposing reinforcing bars is to connect the lower end of the SC pile to the upper end of the lower pile made of a predetermined number of ready-made piles to expose the axial direction embedded in the SC pile as follows. It is the exposure method of the axial reinforcement of the SC pile characterized.
(1) A concrete part having a hollow part is formed in a steel pipe, and a reinforcing bar cage in which the axial reinforcing bars arranged in an annular shape in the concrete part are retained by an upper end plate and a partition plate is embedded as follows. The SC pile structure was configured.
(a) The steel pipe was divided into an upper part and a lower part at a predetermined cutting position along the outer periphery at a predetermined height in the axial direction.
(b) The axial rebar is disposed across the planned cutting position of the steel pipe, and the partition plate is positioned above the planned cutting position of the steel pipe.
(c) The axial rebar is disposed at a position where the upper end of the axial rebar does not protrude above the upper surface of the upper end plate in the axial direction, and the outer periphery thereof is a rebar covering disposed between the upper end plate and the partition plate. The structure was covered with a material.
(2) At the construction site, the SC pile is buried by connecting to the lower pile by a normal method.
(3) In the SC pile, the outer periphery of the steel pipe and the concrete part is cut at the planned cutting position, and the upper part of the steel pipe and the upper part of the concrete part are pulled out together with the upper end plate and the partition plate, and When the reinforcing bar covering material is left, the reinforcing bar covering material is pulled out.
(4) As described above, the upper part of the axial rebar and the upper surface of the remaining concrete part are exposed.

Further, in the invention of the above-described method for exposing a reinforcing bar, the present invention is the method for exposing an axial reinforcing bar of an SC pile, which is configured as follows.
(1) The SC pile structure was constructed as follows.
(a) The axial rebar has a structure in which the upper end is positioned within the thickness of the upper end plate and is not connected to the upper end plate.
(b) The upper end of the plate connecting member is connected to the upper end plate, and the upper end of the plate connecting member is configured not to protrude above the upper surface of the upper end plate in the axial direction.
(c) The partition plate is connected to the lower end portion of the plate connection reinforcing bar, and the lower surface of the partition plate is positioned in the vicinity of the planned cutting position of the steel pipe.
(2) When the steel pipe is pulled out, the partition plate is pulled out together with the upper end plate and the plate connecting rebar.

In the present invention, since the upper end of the axial rebar is located below the upper surface of the upper end plate, there is no protrusion upward from the upper end plate, and the normal pile driving means can be used without special measures. Can be buried. Moreover, since there is no protrusion upward from an upper end plate, the special curing which protects a protrusion in the case of SC pile conveyance is unnecessary, and the conveyance work of SC pile can be simplified.
In addition, because the partition plate is positioned above the planned cutting position of the steel pipe, it is easy to manufacture by reinforcing the steel bar cage with the partition plate when manufacturing the SC pile, and when the SC pile is embedded, the cutting position is clear become. Furthermore, since the partition plate is removed when the SC pile is embedded, the concrete surface of the SC pile is exposed, and the fixing of the footing to the SC pile is enhanced.

In the SC pile according to the present invention, (a) is a plan view and (b) is a front view of a reinforcing bar used. It is an upper end plate used for the SC pile of this invention, (a) is an enlarged plan view of the upper end plate, (b) is an enlarged vertical sectional view of the upper end plate, and (c) is an enlarged view showing the attachment of the axial rebar on the upper end plate. A longitudinal sectional view is shown. It is a partition plate used for the SC pile of this invention, (a) is an enlarged plan view of a partition plate, (b) represents the enlarged longitudinal cross-sectional view showing the attachment of a partition plate and an axial rebar. It is a guide plate used for the SC pile of this invention, (a) represents an enlarged plan view of the guide plate, and (b) represents a partially enlarged plan view of the guide plate. (A)-(d), (f) is the longitudinal cross-sectional view which represented the procedure which assembles the reinforcing bar cage (SC pile) of this invention, (e) is a state of (d), and cut | disconnects at a different angle. The schematic longitudinal cross-sectional view showing only the PC steel bar is shown. (A)-(d) is the schematic longitudinal cross-sectional view showing the construction procedure of SC pile of this invention.

  Embodiments of the present invention will be described with reference to the drawings.

1. Manufacture of SC pile 65

(1) The SC pile 65 is configured by embedding a reinforcing bar 60 in a concrete portion 64 formed in the steel pipe 1 (FIG. 1B). The rebar cage 60 is disposed between the upper end plate 20, the partition plate 30, and the guide plate 40, the axial rebars 10 and 10 disposed so as to penetrate or lock these, and the partition plate 30 and the upper end plate 20. A plate connecting material (PC steel bar 50), a covering pipe 16, and the like, and the axial rebars 10 and 10 are fixed to the upper end plate 20 by a screw fixture 55. In the following, the SC pile 65 is generally manufactured with the axis of the steel pipe 1 lying in a substantially horizontal state. However, in each member, when the SC pile 65 is embedded at the building construction site, The lower side is the lower surface and the upper side is the upper surface.

(2) The member used for this manufacturing method is configured as follows.

    (A) The steel pipe 1 is formed with an inner diameter D01 and an outer diameter D02, and the steel pipe 1 is placed at a distance (height) L0 position from the upper end 2 (the upper surface 21 of the upper end plate 20) in the axial direction (height direction). A scheduled cutting position 7 for cutting the steel pipe 1A and the steel pipe 1B is set. The planned cutting position 7 can be displayed in advance on the outer peripheral surface (not shown).

(B) A threaded portion 13 is formed by threading the upper end 11 side with an axial reinforcing bar 10 (for example, a deformed reinforcing bar) having a length L1. The threaded portion 13 of the axial rebar 10 is formed with a diameter smaller than the minimum axial diameter of the axial rebar 10 via a stepped portion 14 that gradually decreases in diameter from the lower side (FIG. 2C). In the steel pipe 1 of the SC pile 65, a plurality of the axial rebars 10 and 10 are annularly arranged at equal intervals along a circle having a diameter D0. Although the step portion 14 has a structure in which the diameter gradually decreases, the step portion 14 in which the small diameter of the screw portion 13 is formed immediately from the shaft diameter can be formed (not shown).
Moreover, although the thread part 13 was formed in the upper end 11 side of the axial direction reinforcing bar 10, it replaces with the thread part 13 and can also employ | adopt another latching structure (not shown).

    (C) Further, the reinforcing bar covering material used is made of a hard PVC pipe having an inner diameter larger than the maximum outer diameter of the axial reinforcing bar 10 and is referred to as a covering pipe 16. The length of the covering pipe 16 is set corresponding to the planned cutting position 7. The coated pipe 16 is a member for preventing the concrete from adhering to the axial rebars 10 and 10 from being fixed in the concrete portion 64 during the manufacture of the SC pile, and the axial rebar after the construction of the SC pile 65. Any material can be used as long as it can be easily removed from 10.

(D) The upper end plate 20 is made of a donut-shaped steel plate having an inner diameter D1 and an outer diameter D2 (D01 <D2 ≦ D02), and corresponds to the axial rebars 10 and 10 that are annularly arranged at equal intervals of the diameter D0. Thus, the first reinforcing bar insertion holes 24, 24 are formed (FIG. 2). That is, the inner diameter D1 <D0 <the outer diameter D2. Further, a washer having an inner diameter D6 (the outer diameter of the screw portion 13 of the axial rebar 10 <D6 <the maximum outer diameter of the axial rebar 10), that is, a step of the axial rebar 10 so as to cover the outer periphery of the first rebar insertion hole 24. A first washer 26 that can be locked to the portion 14 is prepared (FIG. 2C).
The first washer 26 can be fixed to the lower surface 22 of the upper end plate 20 in advance by welding or the like (not shown). The first washer 26 can be fitted and fixed in advance to the lower surface side of the first reinforcing bar insertion hole 24 by adjusting the outer diameter to the diameter of the first reinforcing bar insertion hole 24 and forming the inner diameter as D6. (Not shown). Further, without opening the first rebar insertion hole 24 downward, a bottom portion can be formed on the lower surface 22 side of the upper end plate 20, and a hole having a diameter D6 can be formed at the bottom portion. 26 is not required (not shown).

(E) Further, the partition plate 30 has a donut shape having an inner diameter D1 and an outer diameter D3 (D3 <D01 so long as it is smaller than the inner diameter D01 of the steel pipe 1 so that it can be inserted into the steel pipe 1 without trouble). The second rebar insertion holes 34 and 34 are formed corresponding to the axial rebars 10 and 10 that are made of a steel plate and are annularly arranged at equal intervals of the diameter D0 in the same manner as the upper end plate 20. The second reinforcing bar insertion hole 34 is formed to be slightly larger than the outer diameter of the covering pipe 16 to be used. A second washer 36 having an inner diameter D7 (maximum outer diameter of the axial rebar 10 <D7 <inner diameter or outer diameter of the coated pipe) is fitted and fixed to the lower surface side of the second reinforcing bar insertion hole 34 (FIG. 3B). . In this case, the second washer 36 and the partition plate 30 are fixed so that the covering pipe 16 does not move until the concrete is placed, and is easily separated when the partition plate 30 is removed during construction. It is fixed with strength. Further, here, a locking recess 35 of the covering pipe 16 is formed by the outer peripheral side of the second rebar insertion hole 34 and the upper surface of the second washer 36 (the outer peripheral side of the opening of the inner diameter D7).
Further, fixed reinforcing bars 37 and 37 having a predetermined length arranged in an annular shape are erected at a substantially right angle on the upper surface 31 of the partition plate 30 and fixed by welding (FIG. 3). The fixing reinforcing bars 37 and 37 serve as so-called anchor bars, and are provided in order to maintain the integrity of the concrete portion 64 (64A) of the SC pile 65 and the partition plate 30.

    (F) The guide plate 40 is made of a donut-shaped steel plate having an inner diameter D4 (inner diameter D1 <D4 of the partition plate 30 or the like) and an outer diameter D5 (D5 <outer diameter D01 of the steel pipe 1). The third rebar insertion hole 44 is formed corresponding to the axial rebars 10 and 10 that are annularly arranged at equal intervals of the diameter D0 (FIG. 4). The third rebar insertion hole 44 is formed with a diameter that allows the axial rebar 10 to be inserted, and forms a communication portion 45 that opens toward the outer periphery so that the axial rebar 10 can be inserted from the outer peripheral side. (FIG. 4B). Therefore, the guide plate 40 has a U-shaped cutout shape from the outer peripheral edge of the donut shape toward the center side.

(G) A PC steel rod 50 is used as the plate connecting member, and the upper end portion 51 of the PC steel rod 50 is fixed to the upper end plate 20 and the lower end portion 52 is fixed to the partition plate 30. For example, an enormous portion (header processing) is formed on the upper end portion 51 of the PC steel bar 50, and a screw portion is formed on the lower end portion 52 (not shown). Corresponding to the configuration of the PC steel rod 50, the upper end plate 20 is formed with a locking hole (header hole) for locking the enormous portion within the thickness of the upper end plate 20, and the partition plate 30 is formed of PC steel. A through hole into which the rod 50 can be inserted is formed (not shown). In this case, the screw portion of the lower end portion 52 and the partition plate 30 are fixed by a nut from the lower side of the lower surface 32 of the partition plate 30. Alternatively, the screw portion (lower end portion 52) of the PC steel rod 50 is fixed to the partition plate 30 with two nuts from both the upper side of the upper surface 31 and the lower side of the lower surface 32 of the partition plate 30 so as to sandwich the partition plate 30. (Not shown).
As the plate connecting material, sufficient compressive strength and rigidity without bending are maintained so that the distance between the upper end plate 20 and the partition plate 30 is kept constant until the concrete is placed, and the upper end plate 20 is applied during construction. At the same time, a material other than the PC steel rod 50 (such as a shape steel or a resin material) can be used as long as it has a tensile strength that allows the partition plate 30 to be pulled out integrally.

(H) A screw fixture 55 is used as a fixture, and the screw fixture 55 is larger than the nut portion 56 above the nut portion 56 and a nut portion 56 that can be screwed into the screw portion 13 of the axial rebar 10. It comprises a head 57 having a diameter (FIG. 2C). The nut portion 56 has an outer diameter that can be inserted into the first rebar insertion hole 24 of the upper end plate 20, and the head portion 57 has a flat hexagonal shape and is larger in diameter than the first rebar insertion hole 24.
When a locking structure other than the screw portion 13 is employed on the upper end 11 side of the axial rebar 10, a fixture having locking means instead of the nut portion 56 is employed (not shown).

(3) Next, a procedure for assembling the reinforcing bar car 60 (configuration and manufacturing method of the reinforcing bar car 60) will be described (FIG. 5).

    (A) The partition plate 30 and the guide plate 40 are arranged in parallel at a predetermined interval, the axial rebars 10 are inserted into the second rebar insertion holes 34 of the partition plate 30, and the lower end of the axial rebar 10 Is inserted into the third rebar insertion holes 44, 44 from the outer peripheral side of the guide plate 40, and the partition plate 30 and the guide plate are attached to the axial rebar 10 (FIG. 3 (b), FIG. 4 (b)). All the axial rebars 10 and 10 are attached to the partition plate 20 and the guide plate 30 (FIG. 5A). In addition, the position of the partition plate 30 in the axial direction of the axial rebars 10 and 10 is determined by the preset scheduled cutting position 7 (that is, L0).

    (B) After (A) or simultaneously with (A), a holding steel material (bundling wire, wire, thin reinforcing bar, etc.) is wound around the axial reinforcing bars 10 and 10 from the outer peripheral side of the guide plate 40, and the axial reinforcing bars 10, 10 is temporarily fixed so as not to move in the radial direction from the third reinforcing bar insertion holes 44, 44 (not shown).

    (C) Subsequently, the covered pipe 16 is covered from the upper end 11 side of each axial rebar 10, 10, the lower end 18 of the covered pipe 16 is inserted into the second through hole 34 of the partition plate 30, and the second washer 36. It is made to contact | abut to the upper surface of (FIG.3 (b)). In this state, the positions of the upper ends 11 and 11 of the axial rebars 10 and 10 are substantially aligned, the first washer 26 is put on the screw portion 13 of each axial rebar 10, and the first washer 26 is locked to the stepped portion 14. (FIG. 5B, FIG. 2C).

    (D) Subsequently, the upper end plate 30 is brought closer from the upper end 11 side of the axial rebars 10, 10, and the threaded portion (upper end portion) 13 of each axial rebar 10 is moved to the first rebar insertion portions 24, 24 of the upper end plate 20. The first washers 26 and 26 are inserted into contact with the lower surface 22 of the upper end plate 20 (FIGS. 5C and 2C). In this state, the threaded portion 13 of the axial rebar 10 (or even the upper portion of the stepped portion 14) is in the first rebar insertion hole 24, and the upper end 11 of the axial rebar 10 (the upper end of the threaded portion 13) is It fits in the 1st reinforcement insertion hole 24, and does not protrude from the upper surface 21 of the upper end board 20 (FIG.2 (c)).

(E) Subsequently, in this state, the third washer 27 is attached to the outer periphery of the nut portion 56 of the screw fixture 55 from the upper surface 21 side of the upper end plate 20, and the nut portion 56 is inserted into the first rebar insertion 24. Then, the nut portion 56 is screwed into the screw portion 13 of the axial rebar 10 (FIG. 5C). In this state, the upper end 11 side of the axial rebars 10 and 10 is fixed to the upper end plate 20.
In this state, the upper end 17 of the covering pipe 16 is in contact with the lower surface of the first washer 26 (the lower surface 22 of the upper end plate 20) (FIG. 2C), and the lower end 18 of the covering pipe 16 is the partition plate 30. 3 is in contact with the upper surface of the second washer 36 (FIG. 3B), the movement of the covered pipe 16 in the vertical direction is restricted, and the lower end 18 of the coated pipe 16 is the second rebar insertion hole of the partition plate 30. The movement of the covering pipe 16 in the direction perpendicular to the vertical direction is also restricted. Therefore, the upper end plate 20 and the partition plate 30 can maintain a constant interval. Moreover, the upper end 17 and the lower end 18 of the covering pipe 16 are substantially sealed, and concrete (mortar) can be prevented from entering the inside of the covering pipe 16.

    (F) After (E) or at the same time as (E), a ring reinforcing bar 46 formed in an arc shape is fixed to the outer peripheral side of the guide plate 40, and the guide plate 40 and the axial reinforcing bars 10, 10 are To fix. Also, spacers 47 and 47 for holding the guide plate 40 (that is, the axial rebars 10 and 10) at a predetermined position (center of the steel pipe 1) are fixed to the guide plate 40 (FIGS. 5D and 4B). )).

    (G) After (E) or at the same time as (E), the lower end 52 side (screw portion side) of the PC steel rod 50 is inserted from the locking hole (not shown) of the upper end plate 20. Subsequently, in a state where the enormous portion (upper end 51 side) of the PC steel rod 50 is locked in the locking hole, the threaded portion on the lower end 52 side of the PC steel rod 50 is protruded from the through hole of the partition plate 30, A nut is screwed and fastened to the threaded portion, and the PC steel bars 50 and 50 are fixed to the upper end plate 20 and the partition plate 30 (FIGS. 5E, 2C, and 3B). Therefore, the PC steel bars 50 and 50 can firmly prevent the gap between the upper end plate 20 and the partition plate 30 from being opened.

    (H) The rebar cage 60 is configured as described above (FIGS. 5 (f) and 1 (b)).

    (I) Subsequently, the lower end side (guide plate 40 side) of the reinforcing bar 60 is inserted from the upper end 2 side of the steel pipe 1, and the upper end plate 20 of the reinforcing bar 60 is fixed to the upper end 2 of the steel pipe 1 by welding. In this state, the lower surface 32 of the partition plate 30 of the rebar cage 60 is located slightly above (several millimeters to several centimeters) above the planned cutting position 7 of the steel pipe 1. It is desirable that the lower surface 32 of the partition plate 30 of the reinforcing bar 60 is located above the planned cutting position 7 of the steel pipe 1 and as close to the planned cutting position 7 as possible.

    (J) Then, the lower end plate 62 matched with the upper end plate (not shown) of the lower pile 67 to be connected is welded and fixed to the lower end 3 of the steel pipe 1 (FIG. 5 (f)).

(K) Subsequently, concrete is poured into the steel pipe 1 by a normal method. At this time, the set distance between the upper end plate 20 and the partition plate 30 can be maintained.
Moreover, SC pile 65 will be comprised if predetermined curing is carried out. A concrete portion 64 having a hollow portion corresponding to the inner diameter D1 of the upper end plate 20 is formed on the inner surface 5 side of the steel pipe 1 (FIGS. 2 (a) and 3 (a)), and the rebar cage 60 is placed in the concrete portion 64. It is buried (FIG. 1 (b)).

2. Construction of SC pile 65 (exposure method of axial rebar 10)

(1) The SC pile 65 is shipped with the screw fixtures 55, 55 removed from the upper end plate 20, and is transported to the construction site. Accordingly, the first reinforcing bar insertion hole 24 is exposed from the upper surface 21 of the upper end plate 20 (FIGS. 1A and 2C), and the upper end 11 of the axial reinforcing bars 10 and 10 is lower than the upper surface 21 of the upper end plate 20. In this SC pile 65, no protrusions are generated upward from the upper surface 21 of the upper end plate 20 because the upper end portion 51 (enlarged portion) of the PC steel rod 50 is within the thickness of the upper end plate 20. Therefore, it is easy to handle the SC pile 65 during transportation from the factory to the building construction site, movement within the building construction site, or construction. Therefore, at the construction site, construction can be performed in the same manner using the same equipment as a normal SC pile.

(2) With a normal construction method, the lower pile 67 and the SC pile 65 connected in a predetermined number are constructed simultaneously with excavation of the pile hole or after excavation of the pile hole. The SC pile 65 is attached to the upper end of the lower pile 67 (FIG. 6A). At this time, when used in the so-called digging method, since there is no protrusion from the upper surface 21 of the upper end plate 20 of the SC pile 65, a normal pile driving machine (Fig. Excavation can be performed with an excavation rod (not shown) while holding the SC pile 65.
In this state, the planned cutting position 7 (partition plate 30) of the SC pile 65 is located above the ground 70 (FIG. 6A).

(3) Subsequently, at the height of the planned cutting position 7 of the steel pipe 1 of the SC pile 65, the outer peripheral side of the steel pipe 1 and the concrete portion 64 is cut with a cutter or the like (FIG. 6B). As described above, this cutting position (scheduled cutting position 7) is located below the lower surface 32 of the partition plate 30. The steel pipe 1 is separated into a steel pipe 1A above the scheduled cutting position 7 and a steel pipe 1B below.

(4) Subsequently, when the steel pipe 1A of the SC pile 65 is pulled upward above the cutting position (scheduled cutting position 7), the upper part 64A of the SC pile 65 (the upper part 1A of the steel pipe 1, the upper end plate 20, the partition plate) 30, the covering pipe 16, the upper part 64 </ b> A of the concrete part 64), and the lower part 64 </ b> B of the SC pile 65 (the lower part 1 </ b> B of the steel pipe 1, the guide plate 40, the lower part 64 </ b> B of the concrete part 64) is left together with the lower pile 67 ( FIG. 6 (c)). At this time, the covering pipes 16 and 16 are usually not included in the SC pile 65A and are left on the axial rebars 10 and 10 (FIG. 6C).
At this time, since the upper end plate 20 and the partition plate 30 are connected by the PC steel bars 50 and 50, and the fixing rebar 37 is fixed to the partition plate 30, by pulling up the steel pipe 1A and the upper end plate 20, The upper part 64A of the concrete part 64 and the partition plate 30 are surely separated and removed together with the SC pile 65A.

(5) Subsequently, the remaining covered pipes 16 and 16 are removed from the axial rebars 10 and 10 (FIG. 6D). As a result, the upper part of the axial rebars 10 and 10 is exposed above the cutting position (scheduled cutting position 7). Therefore, the exposed axial rebar is fixed on the reinforcing bar of the footing, concrete is placed, and the SC pile 65 is fixed. A footing integrated with the lower portion 65B is constructed (not shown).
At this time, the partition plate 30 is removed and the upper surface 64a of the lower portion 64B of the concrete portion 64 is exposed (FIG. 6D), so that the integrity of the footing and the SC pile 65B is enhanced.

(6) In the above, when the SC pile 65A is separated (FIG. 6 (c)), all or part of the covered pipe 16 is removed from the axial rebars 10 and 10 together with the SC pile 65A. There is also.

1 Steel pipe 1A Upper part of steel pipe (removal side)
1B Lower part of steel pipe (remaining side)
2 Upper end of steel pipe 3 Lower end of steel pipe 4 Outer surface of steel pipe 5 Inner surface of steel pipe 7 Planned cutting position of steel pipe 10 Axial rebar 11 Upper end of axial rebar 12 Axial rebar lower end 13 Axial rebar thread 14 Axial rebar thread Step 16 Covered pipe (rebar covering material)
16A Upper part of the coated pipe 16B Lower part of the coated pipe 17 Upper end of the coated pipe 18 Lower end 20 of the coated pipe Upper end plate 21 Upper surface of the upper end plate 22 Lower surface of the upper end plate 24 First reinforcing bar insertion hole 26 of the upper end plate First washer 27 of the upper end plate Second washer 30 of upper end plate Partition plate 31 Upper end of partition plate 32 Lower end of partition plate 34 Second reinforcing bar insertion hole 35 of partition plate Retaining recess 36 of second reinforcing bar insertion hole First washer 37 of partition plate Fixing reinforcing bar of partition plate 40 Guide plate 41 Guide plate upper surface 42 Guide plate lower surface 44 Guide plate third rebar insertion hole 45 Third rebar insertion portion communication portion 46 Guide plate ring rebar 47 Guide plate spacer 50 PC steel rod (plate connecting member )
51 Upper end portion of PC steel bar 52 Lower end portion of PC steel bar 55 Screw fixing tool (fixing tool)
56 Nut portion 57 of the screw fixture 57 Head portion 58 of the screw fixture Third washer 60 of the upper end plate 60 Rebar cage 62 Lower end plate 64 Concrete portion 64A Upper portion of the concrete portion (removal side)
64B Lower part of concrete part (remaining side)
64Ba Top surface of lower part of concrete part 65 SC pile 65A Upper part of SC pile (removal side)
Lower part of 65B SC pile (remaining side)
67 Lower pile 70 Ground

Claims (7)

In the SC pile formed by fixing the upper end plate and, if necessary, the lower end plate on the upper and lower sides of the steel pipe and forming a concrete portion having a hollow portion in the steel pipe, the axial rebar is configured as follows. SC pile with
(1) The steel pipe was divided into an upper part and a lower part at a predetermined cutting position along the outer periphery at a predetermined height in the axial direction.
(2) Across the planned cutting position of the steel pipe, axial rebars are annularly arranged at the upper and lower parts, and a donut-shaped partition plate is provided above the planned cutting position in the length direction of the steel pipe. The axial rebars are penetrated through the partition plate.
(3) A fixing portion is formed at the upper end of the axial rebar, and the upper end of the axial rebar is positioned below the upper surface of the upper end plate.
(4) The fixing portion of the axial rebar is detachably attached to a fixture that is detachably attached to the upper end plate.
(5) Each of the axial rebars was covered with a reinforcing bar covering material disposed between the partition plate and the upper end plate.
(6) The upper end plate and the partition plate are connected by a plate connecting member disposed substantially parallel to the axial rebar.
(7) The upper end plate, the partition plate, the axial reinforcing bar partially covered with the reinforcing bar covering material, and the plate connecting member constitute a reinforcing bar cage, and the reinforcing bar cage is embedded in the concrete portion. It was. The SC pile provided with the axial rebar according to claim 1, which is configured as follows.
(1) A threaded portion was formed at the upper end of the axial rebar, the first rebar insertion hole was formed in the upper end plate, and the upper end of the threaded portion was positioned within the first rebar insertion hole.
(2) A nut portion of a screw fixture locked on the upper surface side of the upper end plate was inserted into the first rebar insertion hole, and detachably screwed into the screw portion.
(3) A second rebar insertion hole was formed in the partition plate to penetrate the axial rebar.
(4) The upper end of the hollow reinforcing bar covering material was brought into contact with the upper end plate, and the lower end was brought into contact with the partition plate, so that the upper and lower sides of the covering material were substantially sealed. The SC pile provided with the axial rebar according to claim 1, which is configured as follows.
(1) The lower surface of the partition plate was positioned directly above the planned cutting position.
(2) Below the planned cutting position, a guide plate is provided in parallel with the partition plate, and an axial rebar is passed through the guide plate, and the guide plate is placed at a predetermined position of the steel pipe on the outer periphery of the guide plate. In order to keep it at a constant value, a spacer arranged along the inner periphery of the steel pipe was attached.
(3) On the upper surface of the partition plate, a covering material locking recess was formed around the second reinforcing bar insertion hole, and the lower surface of the reinforcing bar covering material was positioned. A method of manufacturing a SC pile by placing a rebar cage with an axial rebar in a steel pipe with a predetermined cutting position in the axial direction, injecting concrete, and centrifugally forming it. The manufacturing method of SC pile provided with the axial direction reinforcement characterized by comprising.
(1) The rebar cage structure is configured as follows as follows.
(a) An upper end plate and a partition plate are juxtaposed along the axial direction, the axial rebar is passed through the partition plate, and the upper end of the axial rebar is positioned within the thickness of the upper end plate.
(b) The rebar covering material arranged between the upper end plate and the partition plate covered the axial rebar.
(c) The upper end plate and the partition plate are connected by a plate connecting member that maintains a predetermined interval.
(2) A rebar cage is inserted from the upper end side of the steel pipe, the upper end plate is welded and fixed to the upper end of the steel pipe, and the partition plate is positioned closer to the upper end side than the planned cutting position of the steel pipe.
(3) Subsequently, a fixing tool is attached from the upper surface side of the upper end plate, and the fixing portion on the upper end side of the axial rebar is detachably held.
(4) Subsequently, the concrete is poured into the steel pipe and cured, and after the concrete is solidified, the fixture is removed to form the SC pile. The manufacturing method of the SC pile provided with the axial rebar of Claim 4 characterized by comprising as follows.
(1) The rebar cage structure was constructed as follows.
(a) A first reinforcing bar insertion hole is formed in the upper end plate and a second reinforcing bar insertion hole is formed in the partition plate in accordance with the position of the axial reinforcing bar, and the axial reinforcing bar is arranged on the guide plate arranged below the partition plate. Accordingly, a rebar insertion notch opened in the radial direction was formed, and a threaded portion was formed at the tip of the axial rebar.
(b) The axial rebar is inserted into the second rebar insertion hole of the partition plate, locked to the rebar insertion notch of the guide plate, and the upper end of the screw portion of the axial rebar is connected to the upper end plate of the upper end plate. It was located in the single rebar insertion hole.
(2) Subsequently, the rebar cage is disposed in the steel pipe, the guide plate is disposed near the center in the steel pipe, and the lower end portion of the axial rebar is disposed at a predetermined position.
(3) Subsequently, a screw fixture is inserted into the first rebar insertion hole from above the upper end plate, and the screw fixture is locked to the upper surface of the upper end plate, and the screw fixture and the shaft The screw part of the directional reinforcing bar is screwed and temporarily fixed.
(4) Subsequently, the concrete is poured into the steel pipe and cured, and after the concrete is solidified, the fixture is removed to form the SC pile. An axial rebar of an SC pile characterized by connecting the lower end of an SC pile to the upper end of a lower pile consisting of a predetermined number of ready-made piles and exposing the axial direction embedded in the SC pile as follows. Exposure method.
(1) A concrete part having a hollow part is formed in a steel pipe, and a reinforcing bar cage in which the axial reinforcing bars arranged in an annular shape in the concrete part are retained by an upper end plate and a partition plate is embedded as follows. The SC pile structure was configured.
(a) The steel pipe was divided into an upper part and a lower part at a predetermined cutting position along the outer periphery at a predetermined height in the axial direction.
(b) The axial rebar is disposed across the planned cutting position of the steel pipe, and the partition plate is positioned above the planned cutting position of the steel pipe.
(c) The axial rebar is disposed at a position where the upper end of the axial rebar does not protrude above the upper surface of the upper end plate in the axial direction, and the outer periphery thereof is a rebar covering disposed between the upper end plate and the partition plate. The structure was covered with a material.
(2) At the construction site, the SC pile is buried by connecting to the lower pile by a normal method.
(3) In the SC pile, the outer periphery of the steel pipe and the concrete part is cut at the planned cutting position, and the upper part of the steel pipe and the upper part of the concrete part are pulled out together with the upper end plate and the partition plate, and When the reinforcing bar covering material is left, the reinforcing bar covering material is pulled out.
(4) As described above, the upper part of the axial rebar and the upper surface of the remaining concrete part are exposed. It is comprised as follows, The exposure method of the axial reinforcement of the SC pile of Claim 6 characterized by the above-mentioned.
(1) The SC pile structure was constructed as follows.
(a) The axial rebar has a structure in which the upper end is positioned within the thickness of the upper end plate and is not connected to the upper end plate.
(b) The upper end of the plate connecting member is connected to the upper end plate, and the upper end of the plate connecting member is configured not to protrude above the upper surface of the upper end plate in the axial direction.
(c) The partition plate is connected to the lower end portion of the plate connection reinforcing bar, and the lower surface of the partition plate is positioned in the vicinity of the planned cutting position of the steel pipe.
(2) When the steel pipe is pulled out, the partition plate is pulled out together with the upper end plate and the plate connecting rebar.

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