JP2006077388A - Pile burying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pile burying method capable of easily burying, at low cost, foundation piles capable of developing firm support forces. <P>SOLUTION: This pile burying method comprises the steps of burying a casing and a tip head in the ground while rotating in the state of the tip head 1 having an outwardly expanding blade body 3 at the lower end of a cylindrical casing 19 detachably fitted to the lower end of the cylindrical casing 10, inserting a reinforcement member (reinforcement cage R) in the casing, throwing a pre-cured concrete (readymixed concrete C) in the casing, and extracting the casing from the ground in the released state of the installation of the tip head. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pile embedding method, and more particularly, to a pile embedding method capable of inexpensively and easily embedding a foundation pile capable of exhibiting a strong support force.

Conventionally, pile burying methods such as the pre-boring method and the Nakabori method have a problem in that since a large amount of excavated soil is discharged, the ground is loosened and the bearing capacity of the pile is reduced. Moreover, in addition to a large amount of excavated earth and sand, a large amount of industrial waste in the slime treatment is discharged, and the costs for storage, transportation, treatment and the like are high.
Then, the method of screwing the pile which provided the spiral blade in the outer periphery into the ground as a conventional pile embedding method which solves the said problem is known (for example, refer patent documents 1-3).
However, in Patent Documents 1 to 3, the pile is pushed into the ground while rotating, so in a relatively long pile, the return to the pile is caused by the frictional force of the soil, and the pile is damaged. As a result, the support capacity of the foundation pile may be reduced.

Here, as a conventional pile burying method, a rotating rod is connected to a propulsion head (tip head) rotatably supported at the lower end of the pile, and the pile is returned non-rotatingly while rotating the propulsion head by the rotating rod. There is known one that is embedded in the ground while suppressing the moment (see, for example, Patent Documents 4 and 5).
However, in Patent Documents 4 and 5, in order to rotatably support the propulsion head at the lower end of the pile, it is necessary to provide a large number of rolling members on the propulsion head, and the propulsion head itself becomes expensive and further rotates. In addition to the driving means for rotating the rod, it is necessary to provide clamping means for clamping the upper end of the pile, and the construction is expensive as a whole.

JP 59-85028 A JP-A-7-292666 JP 2002-339353 A JP 2002-81059 A JP 2003-147770 A

  As described above, the present invention has been made in view of the above-described present situation, and an object of the present invention is to provide a pile embedding method capable of embedding and constructing a foundation pile capable of exhibiting a strong support force at low cost.

The present invention is as follows.
1. In the state where the tip head having a wing body extending outward is detachably attached to the lower end portion of the cylindrical casing, the casing and the tip head are embedded in the ground while rotating,
Next, a reinforcing member is inserted into the casing,
Then, put the uncured concrete inside the casing,
Then, the pile burying method characterized by pulling out the casing from the ground in a state where the mounting of the tip head is released.
2. (1) A plurality of divided casings are connected in the axial direction to form a cylindrical divided casing connected body, and a wing body extending outward is provided at the lower end of the divided casing on the lowermost end side of the divided casing connected body. With the tip head detachably attached, the split casing coupling body and the tip head are embedded in the ground while rotating,
Next, (2) a reinforcing member is inserted into the divided casing connector,
Next, (3) after putting the uncured concrete at least inside the split casing on the lowest end side, in a state where the mounting of the tip head is released, the split casing coupling body is moved upward, The split casing on the uppermost end side is pulled out from the ground and separated from the split casing connecting body,
Then, (4) The pile burying method characterized by repeatedly performing the above (3) as necessary to pull out the divided casing coupling body from the ground.
3. A step of embedding in the ground while rotating the casing and the tip head in a state where the tip head having a wing body extending outward is detachably attached to the lower end of the cylindrical casing;
A step of introducing a solidifying material into the casing embedded in the ground;
Inserting a pile into the interior of the casing embedded in the ground;
And a step of pulling out the casing from the ground in a state where the mounting of the tip head is released.
4). 2. The step of inserting the pile body is performed after the step of adding the solidifying material. The pile burying method described.
5. 2. The step of inserting the solidified material and the step of pulling out the casing are performed simultaneously after the step of inserting the pile body. The pile burying method described.
6). 2. When the casing is pulled out from the ground, the solidified material leaked from the lower end portion of the casing is stirred by the stirring portion formed at the lower end portion of the casing. To 5. The pile burying method according to any one of the above.
7). 2. The solidified material is cement milk. To 6. The pile burying method according to any one of the above.
8). 2. The pile as described above, wherein the pile body is a concrete hollow pile. To 7. The pile burying method according to any one of the above.

According to the pile embedding method of the present invention, the tip head remaining at a predetermined depth position in the ground and the hardened concrete are combined, and the peripheral ground on the outer peripheral side of the hardened concrete is solidified to be strong. Can provide a foundation pile that is capable of exerting sufficient support. Moreover, pile embedding work can be completed in a shorter time using a pile embedding machine capable of supporting a long casing in a suspended manner.
According to another pile embedding method of the present invention, the tip head remaining at a predetermined depth position in the ground and the hardened concrete are combined, and the peripheral ground on the outer peripheral side of the hardened concrete is solidified. It is possible to provide a foundation pile that can exert a strong supporting force. Moreover, the pile embedding work can be performed at a lower cost by using a small and simple pile embedding machine that can support the divided casing near the ground surface.
According to still another pile burying method of the present invention, the solidified material joins the tip head and the pile body left at a predetermined depth position in the ground, and solidifies the peripheral ground on the outer peripheral side of the pile body. It is possible to provide a foundation pile that can exhibit a strong support force.
Moreover, when the process of inserting the said pile body is performed after the process of throwing in the said solidification material, a foundation pile can be constructed more simply and rapidly.
Further, when the step of inserting the solidified material and the step of pulling out the casing are performed at the same time after the step of inserting the pile body, the peripheral ground on the outer peripheral side of the pile body is solidified more firmly and uniformly. Can do.
Moreover, when the said solidification material leaked from the lower end part of this casing is made to stir by the stirring part formed in the lower end part of this casing when pulling out the said casing from underground, the surrounding ground on the outer peripheral side of a pile body Can be more uniformly hardened in the axial direction.
Moreover, when the said pile body is a hollow pile made from concrete, a pile can be formed with a cheaper hollow pile.

(Embodiment 1)
The pile embedding method according to the first embodiment includes an embedding process, an insertion process, an input process, and a drawing process described below.

As long as the above “embedding step” is a step of embedding in the ground while rotating the casing and the tip head with the tip head attached to the lower end of the casing, the embedding form, timing, etc. are particularly It doesn't matter. This embedding process is usually performed using a pile embedding machine capable of supporting a long casing in a suspended manner.
As long as the said casing is cylindrical, the material, size, etc. will not be ask | required in particular. This casing is usually a single long object. Examples of the casing include one or a combination of two or more of metal (for example, steel), concrete, and resin.
As long as the tip head has a wing that extends outward, the structure, shape, etc. are not particularly limited. This wing body can be composed of, for example, one or more plate-like members. Examples of the plate member include a spiral plate shape, an inclined plate shape, a horizontal plate shape, a curved plate, and a corrugated plate. Further, the tip head can be detachably attached to the lower end portion of the casing. Examples of the attachment / detachment mode include locking, screwing, fitting, clamping, welding, adhesion, and the like.

As long as the “insertion step” is a step of inserting a reinforcing member into the casing, its insertion form, timing, etc. are not particularly limited.
Examples of the reinforcing member include a reinforcing bar member (for example, a reinforcing bar cage), a steel pipe, and the like. The size of the reinforcing member usually corresponds to the axial length of the casing.

As long as the “input step” is a step of supplying concrete before hardening into the casing, its input form, timing, etc. are not particularly limited.
The amount of concrete input usually corresponds to the size of the internal space of the casing.
In addition, although the above-mentioned "concrete before hardening" usually indicates ready-mixed concrete, it may be concrete mixed by an operator at a construction site. This also applies to the following description.

  As long as the “drawing step” is a step of pulling out the casing from the ground in a state where the tip head is not mounted, the drawing form, timing, etc. are not particularly limited. This extraction process can be extracted while rotating the casing, for example. In this case, when the casing is pulled out from the ground, it is preferable to stir the uncured concrete leaked from the lower end portion of the casing by the stirring portion formed at the lower end portion of the casing. Thereby, the surrounding ground of the outer peripheral side of the concrete after hardening can be hardened more uniformly.

(Embodiment 2)
The pile embedding method according to the second embodiment includes an embedding step (1), an insertion step (2), an input / separation step (3), and a drawing step (4) described below.

In the “embedding step (1)”, the split casing coupling body and the tip head are rotated while the tip head is attached to the lower end portion of the split casing on the lowermost end side of the split casing coupling body. As long as it is a process of embedding in, the embedding form, timing, etc. are not particularly limited. This embedding process is usually performed using a pile embedding machine (a so-called all-swivel machine or the like) that can support the divided casing near the ground surface.
As long as the divided casing coupling body is formed by coupling a plurality of divided casings in the axial direction, the number and size of the coupling are not particularly limited. The material and size of the divided casing are not particularly limited. Examples of the connection form of the divided casings include locking, screwing, fitting, clamping, welding, and adhesion. Moreover, as this division | segmentation casing, 1 type, or 2 or more types of combinations made from metal (for example, steel), concrete, resin, etc. can be mentioned, for example.
As long as the tip head has a wing that extends outward, the structure, shape, etc. are not particularly limited. This wing body can be composed of, for example, one or more plate-like members. Examples of the plate member include a spiral plate shape, an inclined plate shape, a horizontal plate shape, a curved plate shape, and a corrugated plate shape. Moreover, this front-end | tip head can be detachably mounted | worn with respect to the lower end part of the division | segmentation casing of the lowest end side of the said division | segmentation casing coupling body. Examples of the attachment / detachment mode include locking, screwing, fitting, clamping, welding, adhesion, and the like.

  In the embedding step (1), for example, first, [a] with the tip head detachably attached to the lower end of the split casing, the split casing and the tip head are rotated while the tip head is rotated. Next, (b) connect the other divided casing to the upper end side of the divided casing to form a divided casing connected body, and embed it in the ground while rotating the divided casing connected body and the tip head, [C] The step [b] may be repeated as necessary.

As long as the “insertion step (2)” is a step of inserting a reinforcing member into the divided casing coupling body, its insertion form, timing, etc. are not particularly limited.
The reinforcing member can be, for example, a rebar cage. Moreover, the magnitude | size of this reinforcement member respond | corresponds to the axial direction length of a division | segmentation casing coupling body normally.

In the above "input / separation step (3)", after the uncured concrete is introduced into at least the lowermost end of the divided casing, the divided casing coupling body is moved upward in a state where the mounting of the tip head is released. As long as it is a step of moving toward the uppermost side and pulling out the uppermost divided casing from the ground and separating it from the divided casing coupling body, its charging form, separation form, timing, etc. are not particularly limited. In this charging / separating step, for example, the divided casing coupling body can be moved upward while rotating. In this case, when the divided casing coupling body is pulled out from the ground, the uncured concrete leaked from the lower end portion of the divided casing is stirred by the stirring portion formed at the lower end portion of the lowermost split casing. It is preferable. Thereby, the surrounding ground of the outer peripheral side of the concrete after hardening can be hardened more uniformly.
The input amount of the concrete can correspond to the size of the internal space of one of the divided casings, for example.

As long as the “drawing step (4)” is a step of pulling out the divided casing coupling body from the ground by repeating the charging / separating step (3) as necessary, the drawing form, timing, etc. are not particularly limited. Absent. This extraction process can be extracted while rotating the divided casing coupling body, for example. In this case, when the divided casing coupling body is pulled out from the ground, the uncured concrete leaked from the lower end portion of the divided casing is stirred by the stirring portion formed at the lower end portion of the lowermost split casing. It is preferable. Thereby, the surrounding ground of the outer peripheral side of the concrete after hardening can be hardened more uniformly.
In addition, "as needed" means responding to the number of connected divided casing connected bodies. For example, when the number of connected divided casings is two, the charging / separating step (3) is repeated once, and when the number of connected divided casings is three, the charging is performed. -Separation process (3) will be repeated twice.

(Embodiment 3)
The pile embedding method according to the third embodiment includes an embedding process, an input process, an insertion process, and a drawing process described below.

As long as the above “embedding step” is a step of embedding in the ground while rotating the casing and the tip head with the tip head attached to the lower end of the casing, the embedding form, timing, etc. are particularly It doesn't matter. This embedding process is usually performed using a pile embedding machine capable of supporting a long casing in a suspended manner.
As said casing, the form demonstrated with the pile embedding method which concerns on the said Embodiment 1 is applicable, for example.
For example, the form described in the pile embedding method according to the first embodiment can be applied as the tip head.

As long as the “input step” is a step of supplying a solidified material into the casing embedded in the ground, its input form, timing, etc. are not particularly limited.
Examples of the solidifying material include cement milk, mortar, and an adhesive. From the viewpoint of being inexpensive and easy to handle, the solidifying material is preferably cement milk.

As long as the “insertion step” is a step of putting a pile into the casing embedded in the ground, its insertion form, timing, etc. are not particularly limited.
The pile body can be, for example, a hollow pile. Examples of the hollow pile include one or a combination of two or more of concrete, metal (such as steel), and resin. From the viewpoint of being inexpensive and easy to handle, the hollow pile is preferably made of concrete.

  As long as the “drawing step” is a step of pulling out the casing from the ground in a state where the tip head is not mounted, the drawing form, timing, etc. are not particularly limited. This extraction process can be extracted while rotating the casing, for example. In this case, when the casing is pulled out from the ground, it is preferable to stir the solidified material leaked from the lower end portion of the casing by the stirring portion formed at the lower end portion of the casing. This stirring part can protrude outward from the outer peripheral surface of the lower end part of a casing, for example.

  Here, the execution order, timing, etc. of the above-described steps are not particularly limited. For example, [1] a form in which the step of inserting the pile body is performed after the step of introducing the solidified material, and [2] a step of inserting the pile body. Thereafter, a mode in which the step of feeding the solidified material is performed, and [3] a mode in which the step of feeding the solidified material and the step of inserting the pile body are performed at the same time can be mentioned.

  In the case of the above [1] mode, for example, the charging step is a step of charging a predetermined amount of the solidified material into the casing embedded in the ground, and the inserting step is a predetermined amount of the solidified material. It can be a step of inserting the pile body into the inside of the casing in which is put. Thereby, construction of a foundation pile can be implemented more simply and rapidly using one casing.

In the case of the above [2] mode, for example, after the step of inserting the pile body, the step of feeding the solidified material and the step of pulling out the casing can be performed simultaneously. Thereby, a solidification material can be spread uniformly between the inner peripheral side of a casing and the outer peripheral side of a pile body, and the surrounding ground of the outer peripheral side of a pile body can be hardened more firmly and uniformly.
Note that “performed at the same time” means that the casing is pulled out while the solidifying material is being added, regardless of whether the start and end times of each step coincide or not.

In the case of the above [2] form, for example, it can be constructed using a casing comprising a lower casing and an upper casing connected to the upper end of the lower casing and capable of injecting solidified material from the lower end thereof. In this case, the embedding step is, for example, a step of embedding in the ground while rotating the tip head together with the lower casing and the upper casing in a connected state with the tip head attached to the lower end portion of the lower casing. Can be. Moreover, the said insertion process can be a process of inserting the said pile body inside this lower casing in the state which separated the upper casing from the lower casing embedded in the ground, for example. In addition, the charging step is, for example, a step of charging the solidified material injected from the lower end of the upper casing into the lower casing in a state where the upper casing is connected to the lower casing embedded in the ground. Can be. Moreover, the said extraction process can be a process of extracting the connected upper casing and lower casing from the ground in a state where the mounting of the tip head is released, for example.
From the viewpoint of workability of the foundation pile, after the insertion step, with the upper casing connected to the lower casing embedded in the ground, the tip head is rotated again together with the connected lower casing and upper casing. It is preferable to further include a re-embedding step for embedding in the ground.
In addition, the said upper casing can have the cylinder provided in the inside and to which a solidification material is supplied, for example, and the injection nozzle member connected to the lower end side of this cylinder. This cylinder can be provided, for example, so as to be rotatable inside the upper casing and to be extendable and contractable in the axial direction. Thereby, while being able to rotationally press-fit a casing using the existing pile embedding machine, a solidification material can be suitably injected from an upper casing.

  The pile burying method according to the third embodiment can further include, for example, a fixing material charging step. As long as the fixing material charging step is a step of charging the fixing material into the hollow pile (pile body) after the casing is pulled out from the ground, the charging mode, timing, and the like are not particularly limited. Examples of the fixing material include mortar and concrete. By providing this charging step, the tip head and the pile can be more firmly coupled.

  In addition, the said front-end | tip head used with the pile embedding method which concerns on the above-mentioned Embodiment 1-3 provides the wing | blade body which spreads outward on the outer peripheral surface of a cylindrical main body, and is a cylindrical casing ( Or a split casing; the following is omitted), and a tip end head for a foundation pile embedded in the ground, which is provided on the main body and can be engaged with and disengaged from a locked portion provided on the casing. The locking portion and the locked portion can be embedded in the ground while the casing and the tip head are swung by the locking portion and the locked portion. By unlocking the part, the casing can be pulled out from the ground while leaving the tip head in the ground at a predetermined depth, and the wing body has an annular plate having an inner diameter that can be externally fitted to the main body. Divided in the radial direction and identical A plurality of divided plates disposed in a plane, each of the plurality of divided plates being connected to the horizontal portion and the first bent bent upward toward one divided end side; A second bent portion that is continuous with the horizontal portion and bent downward on the other split end side, and in the divided plates adjacent to each other among the plurality of divided plates, The first bent portion and the other second bent portion may be close to each other.

In the tip head, for example, a reinforcing portion may be provided on the upper surface of the bottom wall portion of the main body. Thereby, the front-end | tip head located in the predetermined depth position in the ground and a hollow pile (for example, a steel pipe pile, a PC pile, a cast-in-place concrete pile, etc.) can be combined more firmly. As said reinforcement part, a reinforcing bar part, a steel pipe part, etc. can be mentioned, for example.
In the tip head, for example, the locking portion is a convex portion provided on the upper peripheral surface side of the main body and protruding in the radial direction, and the locked portion is located above the lower end edge of the casing. The protrusion can be inserted into and removed from the notch by the relative movement of the tip head and the casing in the axial direction. The pile embedding method according to claim 1 or 2. Thereby, the attachment / detachment mechanism of the casing and the tip head can be configured with a simpler structure. From the viewpoint of connectivity between the two, it is preferable that a plurality of the convex portions and the cutout portions are provided at equal pitch intervals along the circumferential direction.
In the tip head, for example, the dividing plate may be formed by dividing the annular plate in the radial direction at equal pitch intervals along the circumferential direction. Thereby, the support force with respect to the ground can be improved more.
In the tip head, for example, the bottom wall portion of the main body may be provided with a protruding portion that protrudes downward. As a result, guided excavation can be performed by the protruding portion, and excavation performance can be further improved.

  In addition, from the viewpoints of excavability (thrust) and biting force, the bending angles of the first and second bent portions are set to substantially the same value, and the value is 5 to 30 degrees, more preferably 7 to 27 degrees, particularly 10 to 10. It is preferably 25 degrees. Moreover, the said protrusion part can consist of 1 or 2 or more board | plate materials, for example. Examples of the shape of the plate material include a planar shape, a curved shape, a wave shape, a bent shape, and the like.

Hereinafter, the present invention will be specifically described with reference to the drawings.
(1) Configuration of Tip Head The tip head 1 according to this embodiment will be described. As shown in FIGS. 1 to 3, the tip head 1 includes a cylindrical main body 2, a wing body 3 provided on the outer peripheral surface of the main body 2, and a convex portion 4 provided on the upper end of the main body 2. (Exemplified as a “locking portion” according to the present invention) and a flat plate-like projecting portion 5 provided at the lower end portion of the main body 2 and projecting sharply toward the tip.

The main body 2 has a disk-like bottom wall portion 2a and a peripheral wall portion 2b that rises upward from the periphery of the bottom wall portion 2a and is open upward (see FIG. 3).
The wing body 3 has two divided plates 3a and 3b formed by dividing an annular plate having an inner diameter that can be fitted onto the main body 2, that is, an inner diameter substantially equal to the outer diameter of the main body 2, into two in the radial direction. ing. Each of these divided plates 3a and 3b is disposed in the same horizontal plane. Each of the divided plates 3a and 3b includes a horizontal portion 7, a first bent portion 8 that is continuous with the horizontal portion 7 and bent upward on one divided end side, and downward on the other divided end side. And a second bent portion 9 bent in the direction. And between these division boards 3a and 3b, one 1st bent part 8 and the other 2nd bent part 9 are adjoining.

  Four convex portions 4 are provided on the upper outer peripheral surface of the main body 2 at equal pitch intervals (90 degree intervals) along the circumferential direction. Each of these convex portions 4 protrudes in the centrifugal direction from the outer periphery of the main body 2. Further, each convex portion 4 can be engaged with and disengaged from a notch portion 11 (illustrated as “locked portion” according to the present invention) formed at the lower end portion of the cylindrical casing 10.

  Four notches 11 are formed on the inner peripheral side of the lower end of the casing 10 at equal pitch intervals (90-degree intervals) along the circumferential direction. Each of these notches 11 is formed by cutting away from the lower end edge of the casing 10 upward. Each notch 11 has an axial length that is set to a value greater than the axial length of the convex portion 4, and a circumferential width that is greater than the circumferential width of the convex portion 4. Is set to Further, each notch portion 11 is provided with a hook piece 12 extending in the circumferential direction so as to narrow the insertion opening of the convex portion 4.

  Here, when the tip head 1 and the casing 10 are moved relative to each other in the axial direction with their respective axes aligned, the protrusion 4 of the tip head 1 is inserted into the notch 11 of the casing 10. Escape. Then, when the casing 10 is rotated in a predetermined direction (clockwise) in a state where the convex portion 4 is inserted into the cutout portion 11, the convex portion 4 and the cutout portion 11 are laterally locked, and the casing 10. And the tip head 1 is swung around (see FIG. 3). In addition, even if the tip head 1 moves downward due to its own weight in a state in which the rotation is stopped, the convex portion 4 of the tip head 1 comes into contact with the hook portion 12, so that the tip head 1 falls off from the casing 10. Is prevented. Then, when the casing 10 is rotated in a predetermined direction (counterclockwise) and moved downward with the leading end head 1 positioned, the convex portion 4 escapes from the cutout portion 11, and the leading end head 1 and the casing 10. Will be disengaged.

Example 1
(2) Pile embedding method Next, the pile embedding method which concerns on Example 1 is demonstrated. In this pile burying method, the tip head 1 and the casing 10 are used.

  First, as shown in FIG. 4 (a), the protrusion 4 of the tip head 1 is inserted into the notch 11 of the casing 10, that is, the tip head 1 is attached to the lower end of the casing 10. The casing 10 is pushed downward while rotating clockwise by a lower pile embedding machine (not shown). Then, the leading end head 1 is swung together with the casing 10 by the locking of the convex portion 4 and the notch portion 11. As a result, as shown in FIG. 4B, the tip head 1 and the casing 10 are embedded in the ground.

  Next, as shown in FIGS. 4C and 4D, a reinforcing bar R (illustrated as “reinforcing member” according to the present invention) is inserted into the casing 10. Next, as shown in FIG. 4 (e), a predetermined amount of ready-mixed concrete C is put into the casing 10.

  Thereafter, as shown in FIG. 4 (f), the casing 10 is moved upward while rotating counterclockwise with respect to the tip head 1. Then, the convex part 4 escapes from the notch part 11, the mounting state of the tip head 1 with respect to the casing 10 is released, and the casing 10 is moved upward while the tip head 1 remains at a predetermined depth position in the ground. Moved. At this time, the ready-mixed concrete C leaks from the lower end opening part of the casing 10 and flows into the excavation hole. After that, as shown in FIG. 4G, the casing 10 is completely pulled out from the ground, and the foundation pile is completed by hardening the ready-mixed concrete C.

(3) Effects of Example 1 As described above, in the present Example 1, the lower end portion of the pile body (concrete) and the tip head 1 are firmly connected by the hardening of the ready-mixed concrete C, and the outer peripheral side of the pile body is Since the foundation pile is formed by firmly solidifying the surrounding ground, even if a strong external force is applied due to an earthquake, wind pressure, etc., an extremely strong support force can be exhibited. Moreover, the pile embedding work can be completed in a shorter time using a pile embedding machine that can support the casing 10 that is a long object in a suspended manner.

(Example 2)
(4) Pile embedding method Next, a pile embedding method according to the second embodiment will be described. In this pile burying method, the tip head 1 and a plurality of divided casings described below are used.

  As shown in FIG. 5, the split casings 20 a to 20 d have joint portions 21 on both end sides in the axial direction. By this joint part 21, the divided casings 20a to 20d can be connected in the axial direction to form a divided casing coupling body 22 (see FIG. 6). The split casing 20a is formed shorter than the other split casings 20b to 20d. Further, the split casing 20a has the joint portion 21 only on the upper end side, and has the cutout portion 11 having the same configuration as that of the casing of the first embodiment on the lower end side.

  First, as shown in FIG. 6A, in a state where the convex portion 4 of the tip head 1 is inserted into the cutout portion 11 of the split casing 20a, that is, in a state where the tip head 1 is attached to the lower end portion of the split casing 20a. The split casing 20a is pushed downward by the all-swivel type pile embedding machine 40 while being rotated clockwise. Then, the leading end head 1 is swung together with the divided casing 20 a by the locking of the convex portion 4 and the notch portion 11. As a result, the tip head 1 and the divided casing 20a are embedded in the ground. Next, another divided casing 20b is connected to the upper end side of the divided casing 20a to form a divided casing connecting body 22, and the divided casing connecting body 22 and the tip head 1 are embedded in the ground while rotating. And the said effect | action is repeated as needed and all the division | segmentation casings 20a-20d are embedded in the ground.

  Next, as shown in FIG. 6B, a reinforcing bar R (illustrated as a “reinforcing member” according to the present invention) is inserted into the divided casing coupling body 22.

Subsequently, as shown in FIG.6 (c), the ready concrete C is thrown into the inside of the division | segmentation casings 20a and 20b. Thereafter, the divided casing coupling body 22 is moved upward with respect to the leading end head 1 while rotating counterclockwise. Then, the convex part 4 escapes from the notch part 11, the mounting state of the tip head 1 with respect to the split casing 20a is released, and the split casing coupling body remains with the tip head 1 left at a predetermined depth position in the ground. 22 is moved upward. At this time, the ready-mixed concrete C leaks from the lower end opening part of the divided casing 20a and flows into the excavation hole. Thereafter, the uppermost split casing 20 d is pulled out from the ground and separated from the split casing coupling body 22.
And as shown in FIG.6 (d), the said effect | action is repeatedly performed as needed. As a result, as shown in FIG. 6E, all the divided casings 20a to 20d are pulled out from the ground.

(5) Effect of Example 2 As described above, in the present Example 2, the lower end portion of the pile body (concrete) and the tip head 1 are firmly connected by the hardening of the ready-mixed concrete C, and the outer peripheral side of the pile body is Since the foundation pile is formed by firmly solidifying the surrounding ground, even if a strong external force is applied due to an earthquake, wind pressure, etc., an extremely strong support force can be exhibited. Moreover, the pile embedding work can be performed at a lower cost by using the all-swivel type pile embedding machine 40 capable of supporting the divided casings 20a to 20d which are shorter than the casing 10.

(Example 3)
(6) Pile embedding method Next, a pile embedding method according to the third embodiment will be described. In this pile burying method, the tip head 1 and the casing 10 are used.

  First, as shown in FIG. 7 (a), the protrusion 4 of the tip head 1 is inserted into the notch 11 of the casing 10, that is, the tip head 1 is attached to the lower end of the casing 10. The casing 10 is pushed downward while rotating clockwise by a lower pile embedding machine (not shown). Then, the leading end head 1 is swung together with the casing 10 by the locking of the convex portion 4 and the notch portion 11. As a result, as shown in FIG. 7B, the tip head 1 and the casing 10 are embedded in the ground.

  Next, as shown in FIG. 7C, a predetermined amount of cement milk M (illustrated as “solidifying material” according to the present invention) is put into the casing 10. Next, as shown in FIG. 7 (d), a concrete hollow pile P (illustrated as a “pile” according to the present invention) is inserted into the casing 10. It is assumed that the lower end of the hollow pile P is closed. Then, as shown in FIG.7 (e), the cement milk M will spread uniformly in the axial direction on the outer peripheral side of the hollow pile P inside the casing 10.

  Thereafter, as shown in FIG. 7 (f), the casing 10 is moved upward while rotating counterclockwise with respect to the tip head 1. Then, the convex part 4 escapes from the notch part 11, the mounting state of the tip head 1 with respect to the casing 10 is released, and the casing 10 moves upward while the tip head 1 remains at a predetermined depth position in the ground. To do. At this time, the cement milk M leaks from the opening at the lower end of the casing 10 and flows into the excavation hole. Thereafter, as shown in FIG. 7G, the casing 10 is completely pulled out from the ground, and the foundation pile is completed by hardening the cement milk M.

(7) Effects of Example 3 As described above, in Example 3, the cement milk M is hardened so that the lower end portion of the hollow pile P and the leading end head 1 are firmly connected, and the periphery on the outer peripheral side of the hollow pile P. Since the ground is solidified and the foundation pile is formed, even if a strong external force is applied due to an earthquake, wind pressure, etc., an extremely strong support force can be exhibited.

Example 4
(8) Pile embedding method Next, a pile embedding method according to the fourth embodiment will be described. In this pile burying method, the tip head 1 and the casing 60 described below are used.

  As shown in FIGS. 21 and 22, the casing 60 has a lower casing 60a and an upper casing 60b connected to the upper end of the lower casing 60a. The upper casing 60 b includes a cylindrical body 62 and a plurality of injection nozzle members 63 connected to the lower end portion of the cylindrical body 62. Accordingly, a solidifying material, which will be described later, supplied to the cylindrical body 62 from above is injected from the plurality of injection nozzle members 63 and introduced into the lower casing 60a (see the arrow in FIG. 21). . The cylindrical body 62 has a double cylindrical structure, and is provided so as to be rotatable inside the upper casing 60b and extendable and contractable in the axial direction. Further, the lower end portion of the lower casing 60a has substantially the same configuration as the lower end portion of the casing 10 described above, and the notch portion 11 is formed.

  First, as shown in FIG. 23 (a), as shown in FIG. 23 (b), the axial center of the tip head 1 and the casing 60 (the connected lower casing 60a and upper casing 60b) are aligned. The convex portion 4 of the tip head 1 is inserted into the cutout portion 11 of the lower casing 60a, that is, the tip head 1 is attached to the lower end portion of the lower casing 60a. Next, the casing 60 is pushed downward while rotating clockwise by a suspended pile embedding machine (not shown). Then, the leading end head 1 is swung together with the casing 60 by the locking of the convex portion 4 and the notch portion 11. As a result, as shown in FIG. 23 (c), the tip head 1 and the casing 60 are embedded in the ground.

  Next, as shown in FIG. 23 (d), the upper casing 60b is separated from the lower casing 60a embedded in the ground. Thereafter, as shown in FIG. 23 (e), the PC pile 65 (illustrated as “pile body” and “hollow pile” according to the present invention) is inserted into the lower casing 60 a opened upward. Next, as shown in FIG. 23 (f), the upper casing 60b is connected to the lower casing 60a. Next, as shown in FIG. 23 (g), the casing 60 and the tip head 1 are embedded to a predetermined depth in the ground while being swung around again.

  Next, as shown in FIG. 23 (h), cement milk (illustrated as “solidifying material” according to the present invention) is supplied to the cylindrical body 62 constituting the upper casing 60b. Then, the cement milk is injected from the injection nozzle member 63 and is introduced between the inner peripheral side of the lower casing 60a and the outer peripheral side of the PC pile 65 (see FIG. 21). Then, as shown in FIG. 23 (i), the casing 60 is moved upward while rotating the casing 60 counterclockwise with respect to the leading end head 1 while continuing the injection (injection) of the cement milk. Then, the convex part 4 escapes from the notch part 11, the mounting state of the tip head 1 with respect to the casing 60 is released, and the casing 60 moves upward while the tip head 1 remains at a predetermined depth position in the ground. To do. At this time, cement milk leaks from the lower end opening of the casing 60 and flows into the excavation hole on the outer peripheral side of the PC pile 65. Thereafter, as shown in FIG. 23 (j), the casing 60 is completely pulled out from the ground, and the foundation pile is completed by hardening of the cement milk.

(9) Effects of Example 4 As described above, in Example 4, the lower end portion of the PC pile 65 and the tip head 1 are firmly connected by hardening of the cement milk, and the peripheral ground on the outer peripheral side of the PC pile 65 is used. Since the foundation pile is formed by firmly solidifying, even if a strong external force is applied due to an earthquake or wind pressure, an extremely strong support force can be exhibited.

  In addition, in this invention, it can be set as the Example variously changed within the range of this invention according to the objective and use, without being restricted to the said Examples 1-4. That is, in the third and fourth embodiments, when the casings 10 and 60 are pulled out from the ground (see FIGS. 7 (g) and 23 (j)), the casings 10 and 60 are moved upward while being rotated. The cement milk M leaked from the lower end portion of the casing 10, 60 may be stirred by the stirring portion 30 (for example, a protrusion, a spiral blade, an annular portion, etc.) formed at the outer periphery of the lower end of the 10, 60. Good. Thereby, the cement milk M can be spread uniformly on the surrounding ground.

  In the first to fourth embodiments, the convex portion 4 is provided on the outer peripheral side of the main body 2 of the tip head 1, but the present invention is not limited to this. For example, as shown in FIG. The convex portion 4 may be provided on the inner peripheral side. Moreover, although the square bar-shaped convex part 4 was illustrated in the present Examples 1-3, it is not limited to this, For example, as shown in FIG. Furthermore, in the first to third embodiments, the notch portion 11 is provided on the inner peripheral side of the casing 10 (or the split casing 20a) having a uniform outer diameter in the axial direction. As shown in FIG. 9, the enlarged diameter portion 10 a may be provided at the lower end portion of the casing 10, and the cutout portion 11 may be provided on the inner peripheral side of the enlarged diameter portion 10 a. Furthermore, the notch portion 11 may be provided in the tip head 1 and the convex portion 4 may be provided in the casing 10.

  Further, in the first to fourth embodiments, the attaching and detaching mechanism between the tip head 1 and the casing 10 is configured by the convex portion 4 and the notch portion 11 that can be engaged with and disengaged from each other. However, the present invention is not limited thereto. As shown, the attaching / detaching mechanism may be configured by the frame portion 32 and the convex portion 33 that can be engaged and disengaged with each other. Furthermore, you may make it comprise an attachment / detachment mechanism by a pair of meshing tooth part which can mutually be engaged / disengaged.

  Further, in the first to fourth embodiments, the protruding portion 5 that is a single flat plate pointed toward the tip is exemplified, but the present invention is not limited to this, and for example, a plurality of concave portions are provided on the tip side of the flat plate to protrude. A protrusion 5a (see FIG. 11 (a)), a protrusion 5b made of one rectangular flat plate (see FIG. 11 (b)), or a protrusion having two substantially triangular flat plates arranged at predetermined intervals. 5c (see FIG. 11 (c)) or a protruding portion 5d (see FIG. 11 (d)) in which two rectangular flat plates are arranged at a predetermined interval. Further, the pair of curved portions is formed as a planar substantially Z-shaped protruding portion 5e (see FIG. 12) formed by connecting the flat portions intersecting with each curved portion, or the pair of flat portions intersects with each flat plate portion. A planar substantially Z-shaped projecting portion 5f (see FIG. 13) connected by a flat plate portion, a projecting portion 5g (see FIG. 14) in which a pair of curved plates are provided at a predetermined interval, or a pair of flat plates Or projecting portions 5h (see FIG. 15) provided side by side at a predetermined interval, or a pair of curved plates as projecting portions 5i (see FIG. 16) provided side by side through a central axis (or central hole), A pair of flat plates may be the protruding portions 5j (see FIG. 17) that are provided side by side through a central axis (or central hole).

  Further, in the distal end head 1 according to the first to fourth embodiments, for example, as shown in FIGS. 18 and 19, a plurality of reinforcing bars 35 are crossed and fixed appropriately on the upper surface of the bottom wall portion 2 a (for example, electric A reinforcing bar portion 36 (exemplified as a “reinforcing portion” according to the present invention) formed by welding and screw fixing may be provided. Thereby, in the pile embedding method according to Examples 1 and 2 (a mode in which ready-mixed concrete is introduced into the casing), the lower end portion of the hardened concrete pile and the tip head 1 are more firmly coupled (FIG. 18). reference). Moreover, in the pile embedding method according to Examples 3 and 4 (a configuration in which a hollow pile such as a steel pipe pile or a PC pile is inserted inside the casing), after the casing is pulled out from the ground, a mortar is placed inside the hollow pile P, If a fixing material such as concrete is introduced, the lower end portion of the hollow pile P and the tip head 1 are more firmly coupled to each other by the hardening of the fixing material (see FIG. 19). In particular, if an annular pulling resistance plate 37 having an inner diameter smaller than the inner diameter of the hollow pile P is appropriately fixed to the lower end surface of the ready-made hollow pile P (for example, electric welding fixing, screw fixing, etc.), Stronger resistance can be demonstrated.

  In the first to fourth embodiments, the wing body 3 of the tip head 1 is exemplified by the two divided plates 3a and 3b having the horizontal portion 7 and the first and second bent portions 8 and 9. For example, the wing body may be constituted by one or two or more spiral plates (see FIG. 20), an inclined plate, and the like. Moreover, it is good also as a wing body which consists of a division board formed by dividing an annular plate into three or more.

  It is applied as a construction method for rotary press-fit foundation piles. In particular, it is suitably used as a method for constructing foundation piles such as buildings such as medium- and low-rise houses or small-scale structures.

It is a side view which shows the separation state of the front-end | tip head and casing which concern on a present Example. It is an II arrow directional view of FIG. It is a side view which shows the mounting state of the front-end | tip head and casing which concern on a present Example. It is explanatory drawing for demonstrating the pile embedding method which concerns on the present Example 1. FIG. It is explanatory drawing for demonstrating the division | segmentation casing which concerns on the present Example 2. FIG. It is explanatory drawing for demonstrating the pile embedding method which concerns on the present Example 2. FIG. It is explanatory drawing for demonstrating the pile embedding method which concerns on the present Example 3. FIG. It is explanatory drawing for demonstrating the other form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the other form of the protrusion part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the further another form of the latching | locking part of a front-end | tip head. It is explanatory drawing for demonstrating the other form of a front-end | tip head. It is explanatory drawing for demonstrating the form of the front-end | tip head further. It is explanatory drawing for demonstrating the other form of the wing | blade body of a front-end | tip head. It is explanatory drawing for demonstrating the casing (a cylindrical member is a shortened state) used with the pile embedding method of the present Example 4. It is explanatory drawing for demonstrating the casing (a cylindrical member is an expansion | extension state) used with the pile embedding method of the present Example 4. It is explanatory drawing for demonstrating the pile embedding method of the present Example 4.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1; Tip head 10,60; Casing, 20a-20d; Split casing, 22; Split casing coupling body, 60a; Lower casing, 60b; Upper casing, 65: PC pile, C: Ready-mixed concrete, M: Cement milk, P: hollow pile, R: rebar cage.

Claims (8)

In the state where the tip head having a wing body extending outward is detachably attached to the lower end portion of the cylindrical casing, the casing and the tip head are embedded in the ground while rotating,
Next, a reinforcing member is inserted into the casing,
Then, put the uncured concrete inside the casing,
Then, the pile burying method characterized by pulling out the casing from the ground in a state where the mounting of the tip head is released. (1) A plurality of divided casings are connected in the axial direction to form a cylindrical divided casing connected body, and a wing body extending outward is provided at the lower end of the divided casing on the lowermost end side of the divided casing connected body. With the tip head detachably attached, the split casing coupling body and the tip head are embedded in the ground while rotating,
Next, (2) a reinforcing member is inserted into the divided casing connector,
Next, (3) after putting the uncured concrete at least inside the split casing on the lowest end side, in a state where the mounting of the tip head is released, the split casing coupling body is moved upward, The split casing on the uppermost end side is pulled out from the ground and separated from the split casing connecting body,
Then, (4) The pile burying method characterized by repeatedly performing the above (3) as necessary to pull out the divided casing coupling body from the ground. A step of embedding in the ground while rotating the casing and the tip head in a state where the tip head having a wing body extending outward is detachably attached to the lower end of the cylindrical casing;
A step of introducing a solidifying material into the casing embedded in the ground;
Inserting a pile into the interior of the casing embedded in the ground;
And a step of pulling out the casing from the ground in a state where the mounting of the tip head is released.   The pile embedding method according to claim 3, wherein a step of inserting the pile body is performed after the step of adding the solidifying material.   The pile embedding method according to claim 3, wherein the step of inserting the solidifying material and the step of pulling out the casing are performed simultaneously after the step of inserting the pile body.   The said solidification material leaked out from the lower end part of this casing is stirred by the stirring part formed in the lower end part of this casing when pulling out the said casing from underground. Pile burying method.   The pile embedding method according to any one of claims 3 to 6, wherein the solidifying material is cement milk.   The pile embedding method according to any one of claims 3 to 7, wherein the pile body is a hollow pile made of concrete.

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