JP6603356B2 - Pile reinforcement structure construction method and apparatus - Google Patents

Description

  The present invention relates to a construction method and apparatus suitable for construction of a reinforcing structure for a pile of a building.

Pile is often placed on the ground from the standpoint of improving earthquake resistance. In order to secure sufficient support for the building, it is only necessary to increase the number of piles to be placed or to increase the length of the piles. It becomes.
As a result of intensive studies on a simple method that increases the bearing capacity of the pile without cost, the ground around the pile is removed, the pile is exposed, and a reinforcing material such as aggregate is added to the resulting space. Patent Document 1 discloses a pile reinforcing structure in which a reinforcing layer is formed by charging and compacting. By constructing this pile reinforcement structure, the support for the building is significantly improved.
In addition, the lower surface of the building footing or the like is in contact with both the pile and the reinforcing layer.
See Patent Documents 2 and 3 as documents disclosing techniques related to the present invention.

JP 2011-69187 A JP 2009-35927 A JP 2005-61172 A

  In order to spread the use of such a pile reinforcement structure, it is necessary to establish a simple and inexpensive construction method.

This invention aims at provision of the construction method suitable for construction of the above-mentioned pile reinforcement structure.
That is, the first aspect of the present invention is defined as follows.
It is a construction method of a pile reinforcement structure in which a pile is placed on the ground and a reinforcing layer is formed around the pile,
Prepare an auger provided with a cylindrical part larger in diameter than the pile placed and a stirring blade formed on the outer periphery of the cylindrical part, rotate the cylindrical part while extrapolating to the pile, and from the cylindrical part Injecting solidified material such as cement milk around the pile,
The construction method of the pile reinforcement structure characterized by this.

According to the construction method of the first aspect defined in this way, the auger is rotated in a state where the cylindrical portion is extrapolated to the placed pile, so that the pile does not interfere with the rotation of the auger and the auger is used. Work efficiency is improved.
Moreover, since the axis | shaft of a pile and the axis | shaft of an auger correspond, the reinforcement layer formed by rotation of an auger and injection | pouring of a solidification material is formed uniformly in the circumference | surroundings of a pile, and the reinforcement effect by a reinforcement layer is stabilized.

Here, the shape, material, depth and the like of the pile can be arbitrarily selected according to the required strength and the like. This pile is placed in advance in the ground. A pile attachment can be attached to the tip of the auger, and a pile can be attached to the tip of the auger via this attachment and placed on the ground.
Thereafter, the connection between the auger and the pile is released, and the auger tube portion is set so as to be extrapolated to the pile.

The auger includes a cylindrical portion and a stirring blade. The lower end of the tube part is released and is extrapolated to cover the pile. The inner diameter dimension of the cylindrical portion shall be that the solidified material smoothly flows through the space between the cylindrical portion and the pile and is pushed out to the outside while preventing interference between the two when the cylindrical portion is rotated. In addition, it is preferable to push a solidification material outside from between the inner periphery of a cylinder part lower end and a pile from the viewpoint of ensuring strength of a cylinder part and making outflow resistance small.
The solidifying material can be arbitrarily selected according to the strength required for the reinforcing layer.

Rotate the auger in the first direction (forward rotation) to remove the ground around the pile, then inject the solidified material from the auger tube into the removed ground area, rotate the auger and inject Stir the solidified material.
Even when removing the ground around the pile, by extrapolating the tube portion of the auger to the pile, interference of the pile can be avoided at the time of ground removal work, and this work is facilitated. In addition, the ground can be removed evenly around the pile.
Aggregate may be put into the removed ground region in advance, and then the auger may be rotated by injecting solidified material.
Without removing the ground, it is possible to inject a solidified material while stirring the ground around the pile with an auger, and to form a reinforcing layer made of the solidified material and the raw soil around the pile.

The construction method of the pile reinforcement structure of this invention WHEREIN: The removal method of the ground around a pile is shown. In the construction method according to the embodiment of the present invention, a method for filling a solidified material into a space formed around a pile will be described. Similarly, a method for filling the aggregate and the solidified material will be described. FIG. 3 shows a method of filling a solidified material into a space formed around a pile by using an auger of a different type from FIG. 2. A method of filling the aggregate and the solidified material using the auger of a different type from FIG. 3 will be described. In the construction method of other embodiment, the method of inject | pouring a solidification material, stirring the ground around a pile is shown. The method of inject | pouring a solidification material, stirring the ground around a pile using the auger of a different type from FIG.

Hereinafter, the construction method of the pile reinforcement structure of embodiment of invention is shown.
FIG. 1 shows how the ground around the pile 2 placed on the ground 1 is removed by the auger 4. The auger 4 has a cylindrical portion 5 larger in diameter than the pile 2 and a spiral stirring blade 6 formed on the outer peripheral surface thereof. Here, reference numeral 7 denotes a rotating rod that is rotated and moved up and down by a pile driving machine (not shown). Reference numeral 8 denotes a space formed by the auger 4. As shown in the figure, the space 8 is formed uniformly in the horizontal direction around the pile 2 by extrapolating the cylindrical portion 5 of the auger 4 to the pile 2. .
In the above, the rotating rod 7 and the cylinder part 5 are connected inside, and a fluidized solidifying material is injected into the cylinder part 5 from the upper end side of the rotating rod 7.

After removing the ground from the periphery of the pile 2, the solidified material 10 is injected from the rotating rod 7 side, and the solidified material 10 is discharged from the lower end side of the cylindrical portion 5 to fill the space 8. By rotating and moving the auger 4 up and down, the solidified material 10 is stirred and made uniform. Thereby, a reinforcement layer is formed around the pile 2. Since the cylindrical part 5 is extrapolated to the pile 2, not only the agitation of the solidified material 10 is made uniform, but also the position of the auger 4 is stabilized by being guided by the pile 2, so that the peripheral wall of the space 8 is prevented from collapsing. Is done.
In the above, the rotation direction of the auger 4 when stirring the solidified material 10 is preferably opposite to the rotation direction when removing the ground, but the rotation direction of the auger 4 is switched during the work in order to promote stirring. You can also.
FIG. 3 shows an example in which the solidified material 10 is injected and stirred after the aggregate is put into the bottom of the formed space 8.

FIG. 4 shows another type of auger 14. The auger 14 has a configuration in which a pair of rod-shaped stirring blades 16 are provided so as to protrude from the lower end of the cylindrical portion 5. Of course, the shape, formation position, and number of the stirring blades 16 can be arbitrarily selected.
The auger 14 is suitable for stirring the aggregate 12 and the solidified material 10 as shown in FIG.

In the example of FIG. 6, without removing the ground around the pile 2, the tube portion 5 of the auger 4 is extrapolated to the pile 2 and is rotated and moved up and down while stirring the ground around the pile 2. Inject solidification material. Thereby, the ground of the periphery of the pile 2 becomes a reinforcement layer. Also in this operation, the reinforcement layer is uniformly formed around the pile 2 while preventing the interference between the pile 2 and the auger 4.
FIG. 7 shows an example in which an auger 14 of a type in which a stirring blade 14 is provided only at the lower end of the cylindrical portion 5 is used.

  The present invention is not limited to the description of the embodiments of the invention. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

DESCRIPTION OF SYMBOLS 1 Ground 2 Pile 4, 14 Auger 5, Tube part 6, 16 Agitation blade 10 Solidification material 12 Aggregate

The following matters are disclosed.
(1)
An auger provided with a cylindrical portion that is released at the lower end side and extrapolated to a pile placed on the ground and a stirring blade formed on the cylindrical portion, and connected to the upper end side of the auger, into the cylindrical portion A construction device comprising a rotating rod for injecting a solidifying material,
The rotating rod and the cylinder portion communicate with each other inside, and the solidification material is injected from above the pile toward the pile.
(2)
The construction apparatus according to (1), wherein the stirring blade is formed of a spiral plate.
(3)
The construction device according to (1), wherein the stirring blade is a pair of rod-shaped stirring blades protruding from a lower end of the cylindrical portion.

Claims (3)

It is a construction method of a pile reinforcement structure in which a pile is placed on the ground and a reinforcing layer is formed around the pile,
Preparing an auger provided with a cylindrical portion having a diameter larger than the pile placed and a stirring blade formed on an outer periphery of the cylindrical portion, and first extrapolating the cylindrical portion to the pile;
After the first step, the second step of removing the ground around the pile placed by rotating the cylinder part forward while extrapolating the cylinder part to the pile ,
The auger extends from the outer peripheral surface of the cylindrical portion to the edge of the stirring blade more than the radial distance from the peripheral surface of the pile to the inner peripheral surface of the cylindrical portion when the cylindrical portion is extrapolated to the pile. A method for constructing a pile reinforcement structure in which the radial distance is greater .   The construction method according to claim 1, wherein the stirring blade is formed of a spiral plate.   The construction method according to claim 1, wherein the stirring blade is a pair of rod-shaped stirring blades protruding from a lower end of the cylindrical portion.

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