JP6422192B2 - Pile removal method - Google Patents

Description

The present invention relates to a method for pulling out an existing pile buried in the ground when rebuilding a building structure or the like.

  Building structures such as buildings and condominiums have piles embedded in the ground to support the load. When rebuilding these building structures, it is necessary to remove the embedded existing piles. Conventionally, in order to remove an existing pile, the existing pile is crushed and taken out, or the existing pile is pulled out with a wire and removed.

  Patent Document 1 discloses a method in which a cylindrical casing is embedded around an existing pile, a gripping claw provided at the tip of the casing is engaged with the tip of the existing pile, and then the existing pile is pulled out by pulling up the casing. Have been described.

Patent Document 1: JP 2009-46876 A

However, the thing of patent document 1 had the problem that big force was required in order to pull out an existing pile with a casing, and the apparatus tends to enlarge.

This invention solves the said problem and makes it a subject to extract an existing pile with small force.

In order to solve the above problems, the present invention is a pile drawing method for drawing an existing pile, a preparation step of preparing a cylindrical casing that joins a plurality of divided casings and has a gripping claw at the lowermost end. ,
A casing embedding step of embedding the casing in the ground so as to be located around the existing pile;
An uppermost divided casing removing step of removing the uppermost divided casing from the casing;
Pile pulling step of pulling out the existing pile while leaving the casing in the ground,
A casing pulling process for pulling out the casing ,
Pile pulling characterized in that, when it is determined that the remaining part of the existing pile remains in the casing after the pile pulling step, a gripping claw advancement step is performed to advance the gripping claw into the cylinder of the casing. The construction method is provided.

With this configuration, the load is light by pulling out the existing pile while leaving the casing, and can be pulled out with a small force. In addition, when it is judged that the remaining part of the existing pile remains in the casing, the gripping claw is advanced into the cylinder and the casing is pulled out, so that the existing pile can be completely removed without leaving the remaining part of the existing pile in the ground. Can be pulled out.

  With the pile drawing method of the present invention, an existing pile can be pulled out with a small force.

It is a figure explaining the preparation process in Example 1 of this invention. It is a figure explaining the casing embedding process and the holding nail advance process in Example 1 of this invention. It is a figure explaining the upper division | segmentation casing removal process and the pile drawing-out process in Example 1 of this invention. It is a figure explaining the casing extraction process in Example 1 of this invention. It is a figure explaining the first half of the pile remainder part extraction in Example 2 of this invention. It is a figure explaining the second half of the pile remainder part extraction in Example 2 of this invention.

  The pile drawing method in Example 1 of this invention is demonstrated with reference to FIGS. FIG. 1 is a diagram for explaining a preparation process in Embodiment 1 of the present invention. FIG. 2 is a diagram for explaining a casing embedding process and a gripping claw advancement process according to the first embodiment of the present invention. Drawing 3 is a figure explaining the upper division casing removal process and pile extraction process in Example 1 of the present invention. FIG. 4 is a diagram illustrating a casing drawing process in Embodiment 1 of the present invention.

  In the first embodiment, first, a preparation step is executed to join a plurality of divided casings 1 and a cylindrical casing 2 having a gripping claw at the lowermost end is prepared. More specifically, as shown in FIG. 1, a telescopic crawler pile remover 3 that can be moved by a caterpillar and is easy to assemble is prepared. This telescopic crawler pile remover 3 includes a casing 2 in which five divided casings 1 are joined. Each of the divided casings 1 is joined with a bolt, and a gripping claw 4 is provided at the lowermost end portion of the lowermost divided casing 1 so as to be advanced or retracted into the cylinder of the casing 2.

  In addition, in Example 1, although the number of the division | segmentation casings 1 was five, it is not necessarily limited to this, It can change suitably for convenience, such as the length of the existing pile. For example, it may be 4 or less, or 6 or more. What is necessary is just to expose the front-end | tip of the existing pile P when the uppermost division | segmentation casing 1 in the casing 2 embedded deeply from the front-end | tip of the existing pile mentioned later at least is removed.

  An existing pile P is buried in the ground. The existing pile P is approximately 150 mmφ to 500 mmφ in diameter and 6 m to 22 m in length, and the material is cement (PC pile), pine (pine pile), steel pipe (steel pipe pile), or the like. The casing 2 is selected according to the diameter and length of the existing pile. That is, a casing 2 having an inner diameter larger than the diameter of the existing pile P and a length longer than the length of the existing pile P is prepared. The existing pile P is excavated so that its tip can be seen.

  Next, a casing embedding step for embedding the casing 2 in the ground so as to be positioned around the existing pile P is executed. As shown in FIG. 2A, the casing 2 is positioned and lowered around the existing pile P, and the casing 2 is buried in the ground while rotating as shown in FIG. 2B. And as shown in FIG.2 (c), if the lowest end of the casing 2 is embedded below the lowest end of the existing pile P, embedding will be complete | finished.

  Next, a gripping claw advancement step is performed in which the gripping claw 4 provided at the lowermost end of the casing 2 is advanced into the cylinder of the casing 2 to be engaged with the tip of the existing pile P. That is, when the casing 2 is embedded, the gripping claw 4 has been withdrawn from the cylinder of the casing 2, and is advanced into the cylinder in the gripping claw advancement process after the completion of the embedding. As a result, the gripping claws 4 are spread in the cylinder of the casing 2, and the existing pile P can be pulled out by pulling up the casing 2. FIG. 5 (a-1) shows a state where the gripping claws 4 are retracted from the casing cylinder by broken lines, and FIG. 5 (a-2) shows a state where the gripping claws 4 are advanced by broken lines. When the gripping claw 4 is advanced and positioned in the cylinder of the casing 2, the supporting member of the gripping claw 4 is pushed in by hydraulic pressure, and when the gripping claw 4 is moved away from the cylinder of the casing 2, the hydraulic pressure is released. Then, the support member of the gripping claw 4 may be pulled up.

  Subsequently, the uppermost divided casing is removed by removing the bolt that joins the uppermost divided casing 1 and the lower divided casing to the uppermost divided casing. 1 is pulled upward (see FIG. 3A). Next, a wire engagement process is performed and the wire 5 is engaged above the existing pile P (refer FIG.3 (b)). And the wire 5 is pulled up and the pile extraction process which extracts the existing pile P is performed with the casing 2 left in the ground (see FIG. 3C). The extracted existing pile P is gently lowered onto the ground (see FIG. 3D).

  In addition, in Example 1, although it was set as the structure which pulls out the existing pile P by engaging a wire with the existing pile P, it is not necessarily limited to this, It can change suitably for convenience. For example, you may comprise so that the upper end part of the existing pile P may be hold | gripped and pulled out with a chuck | zipper.

  Here, in the pile drawing process in Example 1, the load to be pulled up is relatively small and can be pulled out with a small force by pulling out only the existing pile P while leaving the casing 2 in the ground. For example, when pulling out the casing 2 and the existing pile P at the same time, the casing 2 and the existing pile P must be pulled out with a large force, which may require a large device and a large space.

  Finally, a casing pulling process is executed to pull out the casing 2 embedded in the ground. For this reason, the uppermost divided casing 1 pulled up earlier is joined to the divided casing 1 located below it again with bolts (see FIG. 4A). At that time, since the gripping claws 4 at the lowermost end of the casing 2 are advanced as described above, when the remaining portion of the pile remains, the remaining portion of the pile can be taken out simultaneously by pulling out the casing 2. That is, when the existing pile P is bent or broken, the remaining part of the pile may remain in the casing 2. The rest of can be completely removed from the ground.

  In the above description, the gripping claw advancement step is performed after the casing embedding step and before the uppermost divided casing removal step, but can be appropriately changed depending on the convenience of the process. For example, the casing drawing step The gripping claw advancement process may be executed immediately before That is, a gripping claw advancement process for advancing the gripping claws 4 into the cylinder of the casing 2 may be executed between the casing embedding process and the casing drawing process.

Thus, in Example 1, it is a pile drawing method for pulling an existing pile, a preparation step of joining a plurality of divided casings and preparing a cylindrical casing having a gripping claw at the lowermost end;
A casing embedding step of embedding the casing in the ground so as to be located around the existing pile;
An uppermost divided casing removing step of removing the uppermost divided casing from the casing;
Pile pulling step of pulling out the existing pile while leaving the casing in the ground,
A casing pulling process for pulling out the casing,
After the casing embedding step to the casing pulling step, a gripping claw advancing step is performed in which the gripping claw is advanced into the cylinder of the casing. By pulling the pile, the load is light and the existing pile can be pulled out with a small force. Moreover, the existing pile can be completely pulled out without leaving the remaining part of the existing pile in the ground by moving the gripping claw into the cylinder of the casing and pulling out the casing.

  The second embodiment is different from the first embodiment in that the gripping claw advancement step is executed when it is determined that the remaining portion of the existing pile remains in the casing after the pile drawing step. The pile drawing method in Example 2 is demonstrated with reference to FIG. 5, FIG. FIG. 5 is a diagram for explaining the first half of the pile remaining portion extraction in the second embodiment of the present invention. FIG. 6 is a diagram for explaining the latter half of the pile remaining portion extraction in the second embodiment of the present invention.

  In Example 2, when it is judged that the remaining part of the existing pile P remains in the casing 2 after the pile drawing process, the gripping claw advancement process is executed. That is, after the pile drawing process, when the length of the extracted existing pile P is shorter than planned, it is determined that the remaining portion of the existing pile P remains in the casing 2 and the holding claw advancement process is executed. In Example 2, it was determined that the remaining part of the existing pile P remains when the length of the existing pile P is shorter than planned, but the present invention is not necessarily limited to this, and can be changed as appropriate for convenience. is there. For example, the weight of the existing pile P may be measured, and it may be determined that the remaining portion of the existing pile P remains when it is lighter than planned.

Specifically, a gripping claw advancement process is performed in which the uppermost divided casing 1 that has been pulled up is joined to the divided casing 1 positioned below it again with bolts, and the gripping claws 4 are advanced into the cylinder of the casing 2. At that time, when the remaining portion of the existing pile P remains in the casing 2, the gripping claws 4 engage with the remaining portion of the existing pile P. Then, the casing 2 is pulled out while the gripping claws 4 of the casing 2 are advanced into the cylinder of the casing 2 (see FIGS. 5A to 5C). Thereby, the remaining part of the existing pile P remaining in the casing 2 can be pulled out, and the existing pile P can be completely removed.

FIG. 5A-1 shows a state in which the gripping claws 4 are retracted, and FIG. 5A-2 shows a state in which the gripping claws 4 are advanced into the cylinder of the casing 2. FIG. When the gripping claw 4 is advanced and positioned within the cylinder of the casing 2, the support member of the gripping claw 4 is pushed in by hydraulic pressure, and when the gripping claw 4 is withdrawn from the cylinder of the casing 2, the hydraulic pressure is released. Then, the support member of the gripping claw 4 may be pulled up.

  If it is determined that the remaining portion of the existing pile P does not remain in the cylinder of the casing 2 after the pile drawing process, the gripping claws 4 may be retracted and the casing 2 may be pulled out. Thereby, there is little load of the soil concerning the holding nail | claw 4, and the casing 2 can be pulled out with small force.

In the second embodiment, the hydraulic pressure is used for the advancement and withdrawal of the gripping claws 4, but the present invention is not necessarily limited to this, and can be appropriately changed for convenience. For example, a mechanism for moving the gripping claw 4 forward and backward by forward and reverse rotation of the casing 2 without depending on the hydraulic pressure may be provided. In that case, when the gripping claw 4 is advanced and positioned in the cylinder of the casing 2, the casing 2 is reversed, and when the gripping claw 4 is withdrawn from the cylinder of the casing 2, the casing 2 can be rotated forward. That's fine.

  Next, the rest of the existing pile P is lowered on the ground. Specifically, as shown in FIG. 6A, the gripping claws 4 are retracted and the remaining portion of the existing pile P is dropped and landed at a place where the remaining portion of the existing pile P is lowered. And the remainder of the existing pile P is lowered | hung to the ground by pulling up the casing 2 (refer FIG.6 (b)).

  As described above, in Example 2, the gripping claw advancement step is performed when it is determined that the remaining portion of the existing pile remains in the casing after the pile drawing step, thereby efficiently removing the existing pile. The remaining portion can be removed, and the existing pile can be completely pulled out without the remaining portion of the existing pile remaining in the ground.

The pile drawing method in the present invention can be widely used in the field of existing pile drawing.

1: Divided casing 2: Casing 3: Telescopic crawler pile remover 4: Grip claw 5: Wire P: Existing pile

Claims (1)

A pile drawing method for drawing an existing pile, a preparation step of joining a plurality of divided casings and preparing a cylindrical casing having a gripping claw at the lowermost end;
A casing embedding step of embedding the casing in the ground so as to be located around the existing pile;
An uppermost divided casing removing step of removing the uppermost divided casing from the casing;
Pile pulling step of pulling out the existing pile while leaving the casing in the ground,
A casing pulling process for pulling out the casing ,
Pile pulling characterized in that, when it is determined that the remaining part of the existing pile remains in the casing after the pile pulling step, a gripping claw advancement step is performed to advance the gripping claw into the cylinder of the casing. Construction method.

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