JP2022069433A - Construction method of hybrid rotary pile, and pile construction jig - Google Patents

Abstract

To provide a construction method of a hybrid rotary pile and a pile construction jig which can press a hybrid rotary pile into a ground extremely efficiently without applying an excessive torque to a joint portion of a lower pile and an upper pile.SOLUTION: A hybrid rotary pile 1 is rotated to be pressed into a ground using a pile construction jig 6. The hybrid rotary pile 1 is formed of: a lower pile 2 having a blade 5 on an outer periphery of a lower pile body 4 comprising a steel pipe; and an upper pile 3 formed of a shaped steel and joined to an upper end portion of the lower pile 2. The pile construction jig 6 includes: a jig body 9 formed in a cylindrical shape into which the upper pile 3 can be inserted; and an engaging portion 7 provided at a lower end portion of the jig body 9 and engaging with an engaged portion 8 provided at an upper end peripheral portion of the lower pile 2. The engaging portion 7 is hung at both sides of the engaged portion 8 along an outer peripheral face of the lower pile body 4. At a lower end portion of the engaging portion 7, there is provided a hook 7a protruding at a lower end side of the engaged portion 8 in an L-shape in a circumferential direction of the lower pile body 4 along the outer peripheral face of the lower pile body 4.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for constructing a hybrid rotary pile and a pile construction jig used in the method for constructing the pile. When a hybrid rotary pile with shaped steel such as steel is press-fitted while rotating in the ground, the joint between the lower pile and the upper pile should not be adversely affected by excessive rotational force, and during construction. The tilt of the piles that have occurred can be easily corrected.

In the field of construction and civil engineering, a temporary gantry was constructed for the purpose of securing a work space for construction machinery and a space for temporary storage of construction materials prior to the main construction (see FIGS. 11 (a) and 11 (b)). ), At that time, H-shaped steel piles are generally used as gantry piles for temporary gantry.

Further, as ready-made steel piles, a rotary pile (Patent Documents 1 and 2) having one or a plurality of blades on the outer periphery of the tip support portion of a pile body made of steel pipe, and a lower portion having blades on the outer periphery of the tip support portion. A rotary pile (Patent Document 3) is known in which a shaped steel pile such as H-shaped steel is joined to the upper end of a pile (rotary pile) as an upper pile.

In this type of rotary pile, not only the blades have the function of the original excavation blades, but also the blades have the function of resistance blades to the surrounding ground after construction, so that even in the case of an intermediate layer shallower than the original support layer, the lower part Since a certain amount of bearing capacity can be secured by the blades of the pile, the pile length can be shortened, and the amount of waste soil associated with drilling can be suppressed, so future demand is expected.

By the way, this kind of rotary pile is installed on the ground surface along the leader of the pile driver, and is installed in the ground by pushing it into the ground while rotating it by a speed reducer. Especially, the latter rotary pile. Has a problem that the joint between the lower pile and the upper pile is susceptible to the adverse effect of excessive rotational force.

As a method for solving such a problem, for example, Patent Document 3 describes a structural steel pile provided with a structural steel pile having an auger screw at the tip and an externally fitted steel pipe in which the structural steel pile is externally fitted and rotationally dug into the ground. The invention of the built-in device is disclosed.

Briefly, the structural steel pile has the shaft of the August cru and the web of the structural steel integrated, and the tip support plate and rotation stabilizing plate inscribed in the outer fitting steel pipe are fixed to the tip of the structural steel, and the outside. The outer-fitting steel pipe has a structure provided with a rotational force receiver that engages with the fitted steel pipe, while the outer-fitting steel pipe is rotatable by a motor suspended from a pile of a working vehicle at the upper portion thereof, and the above-mentioned lower portion thereof. It engages with the rotational force receiver and conducts the rotational force of the outer-fitting steel pipe to the August cru for rotational excavation, and the rotation diameter of the August cru is still larger than the rotation diameter of the outer-fitting steel pipe. ..

Further, Patent Document 4 discloses an invention of a connection structure between an excavation member used at the tip of a foundation pile and functioning as a foundation of a building and a pipe portion connected to the upper end of the excavation member. ing.

Briefly, the excavation member includes a cylindrical substrate whose lower end is closed, and rotary blades on the outer peripheral surface of the substrate, which rotate about an axis together with the substrate to excavate soil, and the outer periphery of the substrate. The surface is provided with a columnar protrusion that protrudes outward in the radial direction.

The tube body portion includes a tubular tube body and a contact portion protruding downward at the lower end portion of the tube body, and the contact portions intersect with each other to form an L-shaped first extension portion and a first portion. A contact surface having an obliquely upward surface normal is formed at an internal angle formed by intersecting the two stretched portions.

By abutting the protrusion on the contact surface and applying a contact force, the excavation member is pressed against the pipe body portion, so that a gap generated at the joint between the excavation member and the pipe body portion is eliminated. The inflow of earth and sand is prevented from the gap.

Japanese Unexamined Patent Publication No. 2016-079619 JP-A-2015-129386 Japanese Unexamined Patent Publication No. 6-272249 Japanese Patent Application Laid-Open No. 2015-200092

However, in the invention of Patent Document 3, since the rotational force of the motor is transmitted to the screw auger by the clutch mechanism, it may be a structurally complicated and expensive pile building device.

Further, in the invention of Patent Document 4, since the L-shaped contact portion protruding from the lower end portion of the pipe main body is formed only on one side of the protrusion protruding from the outer peripheral surface of the base of the excavation member, the pipe main body. Since only the rotational force in one direction can be transmitted to the excavation member, there is a problem that the excavation member cannot rotate freely in the forward and reverse directions.

The present invention has been made to solve these problems, and in particular, the hybrid rotary pile can be freely rotated in any direction clockwise and counterclockwise, and can be pulled out. It is an object of the present invention to provide a method for constructing a hybrid rotary pile that enables the hybrid rotary pile to be installed at a predetermined depth reasonably and extremely efficiently, and a pile construction jig used for the method for constructing the pile. Is.

The present invention rotates a hybrid rotary pile composed of a lower pile having blades on the outer periphery of a lower pile main body made of a steel pipe and an upper pile formed of shaped steel and joined to the upper end of the lower pile. It is a method of constructing a hybrid rotary pile that is press-fitted while being pressed, and is provided at a jig main body formed in a tubular shape through which the upper pile can be inserted and at the lower end portion of the jig main body, and is provided at the lower end portion of the lower end pile. The pile construction has an engaging portion that engages with the engaged portion provided in the pile, and the engaging portion is vertically installed on both sides of the engaged portion along the outer peripheral surface of the lower pile body. It is characterized by using a stake and including the following steps.
(1) A process in which the lower pile is erected on the ground surface along the leader of the pile driver, and a speed reducer that moves up and down along the leader is connected to the upper end of the lower pile.
(2) A step of operating the speed reducer and press-fitting into the ground along the leader while rotating the lower pile by the speed reducer.
(3) A step of temporarily stopping the speed reducer while leaving a part of the upper end of the lower pile on the ground, and disconnecting the speed reducer from the upper end of the lower pile.
(4) The pile construction jig in which the upper pile is previously charged is set up at the upper end of the lower pile along the leader of the pile driver, and the upper pile and the pile are placed at the upper end of the lower pile. The process of joining the lower ends of construction jigs.
(5) A step of operating the speed reducer and press-fitting the lower pile into the ground together with the upper pile while rotating the lower pile via the pile construction jig.
(6) A step of pulling out only the pile construction jig from the ground after the lower pile and the upper pile are press-fitted to the support layer.

In particular, by suspending the engaging portion of the pile construction jig on both sides of the engaged portion along the outer peripheral surface of the lower pile body, the lower pile can be freely rotated in both clockwise and counterclockwise directions. In addition, the lower end side of the engaged portion protrudes in an L shape in the circumferential direction of the lower pile body along the outer peripheral surface of the lower pile body at the lower end portion of the engaging portion. By providing a hook (horizontal part), the lower pile can be pulled out via a pile construction jig, so that hard ground can be easily excavated, and the lower pile body generated during excavation can be easily excavated. The tilt can also be easily corrected. Further, by rotating the lower pile, it is possible to avoid an excessive rotational force acting on the joint portion between the lower pile and the upper pile.

Further, the inner diameter of the jig main body of the pile construction jig can be externally attached to the upper end portion of the lower pile main body and the engaged portion (the upper end portion of the lower pile main body and the engaged portion can be included). By providing the engaging portion in the inner portion of the jig body, the engaging portion can be easily engaged with the engaged portion of the upper end portion of the lower pile body.

That is, when the lower end of the jig body is externally contacted with the upper end of the lower pile body and the engaged portion, and then the pile construction jig is rotated around the axis, the engaged portion and the gap portion w match. At that position, the engaged portion is automatically inserted between the engaged portions.

When the engaged portion is inserted between the engaging portions, the lower end of the jig body is placed on the uppermost blade attached to the upper end of the lower pile body to construct the pile. The jig can be held at the upper end of the lower pile body and does not fall below the lower pile body. Further, a stopper for receiving the lower end portion of the jig body may be separately attached to the outer peripheral surface of the upper end portion of the lower pile body.

In addition, since the engaging portion is housed in the jig body and does not protrude around the jig body and at the lower end, it does not become a resistor in the hole wall when the hybrid rotary pile is press-fitted. It can be press-fitted into the inside very efficiently. In addition, it is possible to prevent damage to the engaging portion when installing or transporting the pile construction jig.

According to the present invention, when constructing a hybrid rotary pile consisting of a lower pile made of steel pipe and an upper pile made of shaped steel such as H-shaped steel joined to the upper end of the lower pile, the lower pile is rotated. By press-fitting the piles, the joints between the lower pile and the upper pile can be press-fitted into the ground without applying an excessive rotational force.

Further, the engaging portions provided at the lower end of the pile construction jig are vertically installed along the outer peripheral surface of the lower pile pile main body on both sides of the engaged portions provided at the upper end of the lower pile. As a result, the lower pile can be freely rotated in both clockwise and counterclockwise directions, and the lower side of the engaged portion is placed on the lower end of the engaging portion on the outer peripheral surface of the lower pile body. Since a hook that protrudes in an L shape in the circumferential direction of the lower pile body is provided along the above, the lower pile can be pulled out, so that hard ground can be easily dug, and it occurs during excavation. The tilt of the pile can be easily corrected.

It is a front view of the pile construction jig used when the hybrid rotary pile made of a steel pipe and a shaped steel is rotationally press-fitted into the ground, which is one embodiment of the present invention. FIG. (A) is a partially enlarged view of a hybrid rotary pile and a jig for pile construction, and FIG. (B) is a cross-sectional view taken along the line in FIG. (A). It is a front view which shows the state which the lower end part of the pile construction jig is engaged with the lower end part of the lower pile of a hybrid rotary pile. An example of a hybrid rotary pile is illustrated. FIG. (A) is a front view, and FIG. (B) is an enlarged cross-sectional view taken along the line in FIG. (A). Other embodiments of the pile construction jig, FIG. (A) is a partially enlarged view of the hybrid rotary pile and the pile construction jig, and FIG. (B) is a cross-sectional view taken along the line of Ha-ha in FIG. (A). be. It is a front view which shows the state which the lower end part of the pile construction jig is engaged with the lower end part of the lower pile of a hybrid rotary pile. Other embodiments of the pile construction jig, FIG. (A) is a partially enlarged view of the hybrid rotary pile and the pile construction jig, and FIG. (B) is a cross-sectional view taken along the line Nini in FIG. (A). be. It is a front view which shows the state which the lower end part of the pile construction jig is engaged with the lower end part of the lower pile of a hybrid rotary pile. Other embodiments of the pile construction jig, FIG. (A) is a partially enlarged view of the hybrid rotary pile and the pile construction jig, and FIG. (B) is a cross-sectional view taken along the line in FIG. (A). be. FIGS. (A) to (d) are explanatory views showing a construction procedure of a hybrid rotary pile using a pile construction jig. It is a temporary gantry using a hybrid rotary pile as a gantry pile, and FIG. 1A is a partial perspective view and FIG. 3B is a partial plan view.

FIG. 1-9 shows an embodiment of the present invention, in which the rotational force of the speed reducer installed in the pile driver is applied to the hybrid rotary pile when the hybrid rotary pile and the hybrid rotary pile are press-fitted while rotating in the ground. It is an illustration of a pile construction jig to be transmitted to.

In the figure, the hybrid rotary pile 1 is formed of a lower pile 2 and an upper pile 3 joined to the upper end of the lower pile 2, and the lower pile 2 is a lower pile main body 4 made of a steel pipe and the lower pile main body 4. It has one or more blades 5 attached to the outer circumference, and is engaged with an engaging portion 7 formed at the lower end of a pile construction jig 6 to be described later on the upper end outer peripheral surface of the lower pile main body 4. Part 8 is formed.

The engaged portion 8 is formed of a vertically long rectangular parallelepiped steel piece, and the steel piece is attached to the outer peripheral surface of the upper end of the lower pile body 4 by welding or mounting bolts along the pipe axis direction of the lower pile body 4. Further, the lower pile main body 4 is attached at equal intervals (for example, at intervals of 45 ° or 90 °) in the circumferential direction.

Further, the steel piece as the engaged portion 8 is attached so that the upper end side portion (for example, the upper half) projects above the upper end surface of the lower pile body 4 by a predetermined length and is attached to each other in the diameter direction of the lower pile body 4. It is installed facing each other.

The bolted steel piece is removable, and a steel piece having an optimum cross-sectional diameter and length is attached according to the magnitude of the rotational force transmitted to the lower pile 2.

One blade 5 is attached to the tip of the lower pile main body 4, and one or a plurality of blades 5 are attached at equal intervals above the tip. Further, the blades 5 are attached in a disk shape that is continuous for one rotation in the circumferential direction of the lower pile main body 4 or in a spiral shape that is continuous for several rotations in the circumferential direction of the lower pile main body 4.

Further, the blades 5 are attached to the outer peripheral surface of the lower pile body 4 by welding or mounting bolts, and in particular, the bolted blades 5 are removable, and the outer diameter, quantity and / or are according to the bearing capacity of the pile tip formation. By changing the interval, a predetermined supporting force can be obtained even in an intermediate layer shallower than the original supporting layer.

The upper pile 3 is made of shaped steel such as H-shaped steel, I-shaped steel or channel steel, or cross-shaped steel, and is joined to the upper end portion of the lower pile main body 4 by welding or mounting bolts.

Further, the upper pile 3 can be arbitrarily extended in length by adding it according to the depth of the support layer, and the upper pile 3 is made of shaped steel such as H-shaped steel or cross-shaped steel. Therefore, the joining with the lower pile 2 and the joining between the upper piles 3 can be easily joined by welding or joining bolts using the flange and / or the web of the upper pile 3, and further, the upper part can be joined. The pile 3 is erected on the ground as a temporary pillar, and members such as beams and braces can be easily joined by using a flange and / or a web as a joint.

The pile construction jig 6 has a jig main body 9 and a plurality of engaging portions 7 formed at the lower ends of the jig main body 9, and the jig main body 9 is substantially the same as the lower pile main body 4 of the lower pile 2. It is formed of a steel pipe having an outer diameter of the same diameter and an inner diameter through which the upper pile 3 can be inserted.

The engaging portion 7 is formed of a steel piece having a rectangular cross-sectional shape and a vertically long L-shape, and the steel piece is attached to the outer peripheral surface of the lower end portion of the jig body 9 by welding or mounting bolts, and is cured. The tool body 9 is attached at predetermined intervals in the circumferential direction.

Further, each engaging portion 7 is attached so that the lower end side portion (for example, the lower half) protrudes downward from the lower end surface of the jig main body 9 by a certain length, and the two engaging portions 7 are adjacent to each other in the circumferential direction of the jig main portion 9. A pair is formed for each of the engaging portions 7 and 7, and one steel piece is attached to each pair in an inverted L shape.

Further, the hooks (horizontal portions) 7a and 7a at the lower ends are attached so as to face each other and have a gap portion w slightly wider than the lateral width of the engaged portion 8 between the facing hooks 7a and 7a.

Then, at the same time that the pile construction jig 6 is set up in the upper end portion of the lower pile 2, the engaged portions 8 and 8 of the lower pile 2 are between the engaging portions 7 and 7 of each pair and between the hooks 7a and 7a. It is designed to be inserted from the gap w of.

Further, with the engaged portion 8 inserted between the engaging portions 7 and 7 of each pair, the pile construction jig 6 rotates around its axis, and at the same time, is engaged with one of the engaging portions 7 and 7. By engaging (contacting) the engaging portion 8 in the circumferential direction of the pile construction jig 6, the lower pile 2 rotates clockwise or counterclockwise together with the pile construction jig 6. ..

Further, the engaged portion 8 is located on one side of the engaged portions 7,7, and the lower end portion 8a of the engaged portion 8 is engaged (contacted) with one hook 7a of the engaged portions 7,7. By doing so, the lower pile 2 can be pulled up together with the pile construction jig 8.

With such a configuration, the pile construction jig 6 is alternately rotated clockwise and counterclockwise, and raised and lowered while the engaged portion 8 is inserted between the engaging portions 7 and 7. , The lower pile 2 can be rotated clockwise / counterclockwise together with the pile construction jig 6 and can be raised and lowered, thereby applying an excessive rotational force to the joint between the lower pile 2 and the upper pile 3. Without this, the lower pile 2 can be rotationally press-fitted together with the upper pile 3 to a predetermined depth very efficiently.

FIGS. 5 and 6 show other embodiments of the pile construction jig, and each pair of engaging portions 7 and 7 does not have hooks (horizontal portions) 7a and 7a at the lower ends and has a rectangular cross-sectional shape. It can be easily manufactured because it is formed in a simple columnar shape that is continuous along the axial direction of the lower pile 2.

Further, if the end-spreading tapered surfaces 7b and 7b extending in a figure eight shape in the lower end direction are formed to face each other on the facing surfaces of the lower ends of the engaging portions 7 and 7 of each pair, the engaging portions 7, 7 are formed. Even if the gap portion w of 7 is narrow, the engaged portion 8 of the lower pile 2 can be smoothly inserted between the engaging portions 7 and 7.

7 and 8 also illustrate other embodiments of the present invention, in which the jig body 9 of the pile construction jig 6 is the upper end portion and the engaged portion of the lower pile body 4 of the lower pile 2. It has an inner diameter that can be externally attached to 8, and the engaging portions 7 and 7 are formed on the inner peripheral surface of the lower end portion of the jig base 9.

Further, guide ribs 10 are attached between the engaging portions 7 and 7 adjacent to each other in the circumferential direction of the jig main body 9, except for the section of the gap portion W. The guide rib 10 is formed of a steel piece forming an arc along the inner peripheral surface of the jig body 9, and the steel piece is attached at the same level as the hooks 7a, 7a of the engaging portions 7,7. Moreover, it is horizontally attached along the inner peripheral surface of the jig body 9.

FIG. 9 also illustrates another embodiment of the present invention, in which the jig main body 9 of the pile construction jig 6 has an inner diameter that can be externally attached to the lower pile main body 4 and the engaged portion 8 of the lower pile 2. The engaging portions 7 and 7 are formed on the inner peripheral surface of the lower end portion of the jig body 9. Further, the engaging portion 7 does not have the hook 7a, and the engaging portion 7 is formed in a columnar shape in the axial direction of the lower pile main body 4.

Further, guide ribs 10 are attached between the engaging portions 7 and 7 adjacent to each other in the circumferential direction of the jig main body 9, except for the section of the gap portion W. The guide rib 10 is attached at the same level as the lower ends of the engaging portions 7 and 7, and is attached horizontally along the inner peripheral surface of the jig body 9.

In any of the embodiments of FIGS. 7 to 9, since the engaging portions 7 and 7 are mounted in the jig main body 9 and do not protrude to the lower end portion of the jig main body 9, the lower end portion of the pile construction jig 6 is used. It can be easily engaged with the upper end portion of the lower pile 2.

That is, the lower end portion of the jig main body 9 is circumscribed with the upper end portion of the lower pile main body 4 and the engaged portion 8, and the jig main body 9 is rotated around the axis thereof, thereby causing the engaged portion 8 and the gap portion w. The engaged portion 8 is inserted between the engaging portions 7 and 7 at the positions where the positions of the above coincide with each other.

In a state where the lower end portion of the jig body 9 is in contact with the upper end portion of the lower pile body 4 and the engaged portion 8, the hook (horizontal portion) 7a of the engaging portion 7, the guide rib 10 and the engaged portion 8 Since the jig main body 9 does not fall due to the upper end portion coming into contact with the upper and lower portions, the pile construction jig 6 can be freely rotated around the axis at the upper end portion of the lower pile main body 4.

Further, when the engaged portion 8 is inserted between the engaging portions 7 and 7, the lower end portion of the jig main body 9 is placed on the blade 5 attached to the upper end portion of the lower pile main body 4. As a result, the pile construction jig 6 will not fall any further. A stopper (not shown) for receiving the lower end portion of the jig main body 9 may be separately attached to the outer peripheral surface of the upper end portion of the lower pile main body 4.

Further, since the engaging portions 7 and 7 are housed in the jig main body 9 and do not protrude to the lower end portion of the jig main body 9, the engaging portions 7 and 7 are prevented from being damaged when handling the pile construction jig 6. can do.

The pile construction jig 6 thus formed is connected to the speed reducer 12 of the pile driver 11 and moves up and down along the leader 13 together with the speed reducer 12 while being rotated by the speed reducer 12. ( See Figure 10).

Next, a method of constructing a hybrid rotary pile using the pile construction jig 6 of the present invention will be described (see FIGS. 10 (a) to 10 (d)).
(1) First, the lower pile 2 is vertically erected on the ground surface along the leader 13 of the pile driver 11, and the speed reducer 12 is connected to the upper end of the lower pile 2.
(2) Next, the speed reducer 12 is operated, and the lower pile 2 is rotated by the speed reducer 12 and press-fitted into the ground along the leader 13. Then, the speed reducer 12 is temporarily stopped, leaving a part of the upper end portion of the lower pile 2 on the ground, and the speed reducer 12 is temporarily separated from the upper end portion of the lower pile 2.
(3) Next, the pile construction jig 6 prepared by inserting the upper pile 3 into the inside is vertically erected on the upper end of the lower pile 2 along the leader 13. Then, the lower end portion of the upper pile 3 is joined to the upper end portion of the lower pile 2, and the lower end portion of the pile construction jig 6 is engaged with the upper end portion of the lower pile 2.
In this case, at the same time that the pile construction jig 6 is erected at the upper end of the lower pile 2, the engaged portion 8 of the lower pile 2 is hooked 7a between the engaging portions 7 and 7 of the pile construction jig 6. By being inserted from the gap portion w between 7a, the lower end portion of the pile construction jig 6 is engaged with the upper end portion of the lower pile 2. Further, the lower end portion of the upper pile 3 may be joined to the upper end portion of the lower pile main body 4 of the lower pile 2 by welding or by joining a joining plate and a joining bolt.
Even if the upper pile 3 is erected in advance of the upper end portion of the lower pile 2, then the pile construction jig 6 is placed on the upper pile 3, and the lower end portion is engaged with the upper end portion of the lower pile 2. good.

(4) Next, the speed reducer 12 is operated again, and the lower pile 2 is rotated together with the pile construction jig 6 while being press-fitted into the ground together with the upper pile 3. When the lower pile 2 cannot be smoothly press-fitted due to hitting a hard layer during the construction of the lower pile 2, or when the lower pile 2 is tilted at an angle, the pile construction jig 6 is used together with the lower pile 2. The lower pile 2 can be smoothly press-fitted by rotating it clockwise and counterclockwise several times, or by raising and lowering it while rotating it forward and reverse, and the inclination of the lower pile 2 can be easily corrected. can.
(5) Then, if the lower pile 2 and the upper pile 3 can be installed in the predetermined stratum, only the pile construction jig 6 is separated from the upper end of the lower pile 2 and pulled out from the ground to construct the hybrid rotary pile 1. Complete.

The present invention comprises a hybrid rotary pile consisting of a lower pile having blades on the outer periphery of a lower pile body made of steel pipe and an upper pile formed of shaped steel and joined to the upper end of the lower pile. It is possible to rotationally press-fit into the ground extremely efficiently without applying an excessive rotational force to the joint with the pile, and it is possible to easily correct the inclination of the hybrid rotary pile that occurs during construction.

1 Hybrid rotary pile 2 Lower pile 3 Upper pile 4 Lower pile body 5 Blade 6 Pile construction jig 7 Engagement part
7a hook (horizontal part)
7b taper 8 engaged part
8a Lower end 9 Jig body
10 Guide rib
11 Pile driver
12 reducer
13 Leader w Gap

Claims (4)

A hybrid rotary pile consisting of a lower pile having blades on the outer periphery of the lower pile body made of steel pipe and an upper pile formed of shaped steel and joined to the upper end of the lower pile is press-fitted while rotating in the ground. It is a method of constructing a hybrid rotary pile, which is provided at a jig main body formed in a tubular shape through which the upper pile can be inserted, and at the lower end portion of the jig main body, and is provided at the upper end outer peripheral portion of the lower pile. A pile construction jig having an engaging portion that engages with the engaged portion, and the engaging portion is vertically installed on both sides of the engaged portion along the outer peripheral surface of the lower pile body. A method for constructing a hybrid rotary pile, which comprises the following steps.
(1) A process in which the lower pile is erected on the ground surface along the leader of the pile driver, and a speed reducer that moves up and down along the leader is connected to the upper end of the lower pile.
(2) A step of operating the speed reducer and press-fitting into the ground along the leader while rotating the lower pile by the speed reducer.
(3) A step of temporarily stopping the speed reducer while leaving a part of the upper end of the lower pile on the ground, and disconnecting the speed reducer from the upper end of the lower pile.
(4) The pile construction jig in which the upper pile is previously charged is set up at the upper end of the lower pile along the leader of the pile driver, and the upper pile and the pile are placed at the upper end of the lower pile. The process of joining the lower ends of construction jigs.
(5) A step of operating the speed reducer and press-fitting the lower pile into the ground together with the upper pile while rotating the lower pile via the pile construction jig.
(6) A step of pulling out only the pile construction jig from the ground after the lower pile and the upper pile are press-fitted to the support layer. A hybrid rotary pile consisting of a lower pile having blades on the outer periphery of the lower pile body made of steel pipe and an upper pile formed of shaped steel and joined to the upper end of the lower pile is press-fitted while rotating in the ground. It is a pile construction jig used at the time, and is provided at the lower end portion of the jig main body and the upper end outer peripheral portion of the lower pile, which is formed in a tubular shape into which the upper pile can be inserted. It has an engaging portion that engages with the provided engaged portion, and the engaging portion is vertically provided on both sides of the engaged portion along the outer peripheral surface of the lower pile body. Pile construction jig. In the pile construction jig according to claim 2, the lower end side of the engaged portion is placed on the lower end portion of the engaging portion along the outer peripheral surface of the lower pile body in an L shape in the circumferential direction of the lower pile body. A jig for rotating piles, characterized in that a hook that protrudes into the pile is formed. In the pile construction jig according to claim 2 or 3, the jig main body has an inner diameter that can be externally attached to the upper end portion of the lower pile main body and the engaged portion, and the engaging portion is the curing portion. A jig for pile construction, which is characterized by being provided inside the main body of the tool.

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