JPS6192214A - Method of pulling out pile - Google Patents

Abstract

PURPOSE:To easily pull out a pile, by a method wherein, after a pile is edge-cut through excavation of a casing auger having a screw blade, the pile is pulled off together with the auger through reversing of the auger as refiling with soil is effected from the outer side of the auger. CONSTITUTION:With a casing auger 3 being rotated, the auger is lowered by excavation to a level lower than that of the lower end of a pile 2. A wire rope 16 is connected to the pile 2, and the rope 16 is secured to a wire securing tool 13 of the auger 3. With the rotation of the auger 3 being reversed, earth 18, discharged resulting from edge cutting excavation, is guided to the interior of the auger 3 from the outside of the auger 3, and the earth 18 in the hole 17 is consolidated to be raised. Further, when the auger 3 is raised by reversing, the pile 2 connected to the rope 16 is raised together with the auger and pulled out from a ground.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a drawing method for foundation piles, and particularly to a drawing method using a screw casing.

[Prior art and its problems]

Architectural structures generally consist of an above-ground building and an underground foundation, and in particularly large structures, column-shaped foundation piles may be buried beneath the foundation to stabilize the structure. This has been done traditionally. □ Therefore, when building a new structure on land after demolishing an old building structure, pulling out the foundation piles as described above is an essential foundation work process.

However, the conventional method of pulling out foundation piles,
The construction method used is to drive a tubular casing around the outer circumference of the pile, cut the edge of the pile fence from the ground, and then either handle the pile or pull it out together with the casing.

However, in the case of the method of pulling out only the Mira pile, it is necessary to remove the soil between the casing and the pile, and in the case of the method of pulling out the pile together with the casing, it is necessary to remove the soil from the casing after pulling out the casing. A process for extracting the piles was required, and both the former and the latter processes required a lot of time and labor.

In addition, aged piles are prone to breakage, so there is a problem that the lower end of the pile is left underground during the anti-pulling process.Furthermore, according to the above construction method, it is necessary to fill in the holes after the pile is pulled out. First, simply filling in earth and sand would not consolidate the soil, which could lead to ground subsidence and a decrease in ground strength.

[Purpose of the invention]

In view of this, the present invention uses a casing auger with screw blades to cut the edge of a pile by digging the auger, and then rotates the auger in the opposite direction to increase the earth pressure at the bottom of the pile and push the pile up. As a result, the process is simpler than the conventional construction method, it does not take much time to pull out the piles, it can be pulled out reliably without damaging the piles, and the holes can be backfilled at the same time as the piles are pulled out. This was done for the purpose of providing a method for pulling out piles.

[Summary of the invention]

In order to achieve the above object, the present invention uses a casing auger provided with screw blades around the hollow body to edge-cut the pile and the ground around it over the entire length of the pile, and then The wire ropes are connected and fixed by a wire fixture above the casing auger, and then the casing auger is reversed and the earth and sand discharged by the edge cutting is backfilled from the outside of the casing auger. This construction method is characterized by the fact that the piles are pulled out together with the auger.

[Embodiments of the invention]

The present invention will be explained below with reference to embodiments shown in FIGS. 1 to 5.

First, as shown in Figure 1 (a), the ground! Dig out the head of the existing pile 2 that has been driven into 81 as a foundation pile, and install the pile 2 (
Attach a casing auger 3 with an inner diameter larger than ¥ to the drilling machine and dig into the ground around the pile 2? A1. excavate.

Here, the drilling machine is a working machine 5 having a tower 4 as shown in FIG. 2, and a top sheave 6 is provided at the top of the tower 4. The wire 7 has one end fixed to the hoisting machine on the work machine 5 side, and the other end fixed to the top sheave 6.
It is connected to the drive unit 8 via. This drive section 8 is made up of a motor, a motor, a speed reducer, etc., and is connected to the casing auger 3 provided at the bottom via a connector 9.

FIG. 3 schematically shows only the casing auger 3 and the drive section 8. The casing auger 3 has a predetermined length, and a screw blade 10 is screwed over the entire length on the outer periphery. A gear 11 provided directly connected to the motor 8 and a gear 12 provided on the outer periphery of the upper part of the casing auger 3 mesh with each other to cause forward and reverse rotation.

Further, the wire fixture 13 is provided on the upper part of the casing auger 3, similarly to the drive section 8.

Further, near the lower end of the casing auger 3, screw blades 14 of an appropriate length are provided on the inner side in the same direction as the outer blades.

Here, 15 is a bearing between the wire fixture 13 and the casing auger 3.

However, as shown in FIG. 1(a), the casing auger 3
The excavation is stopped when the tip of the auger 3 descends to a position somewhat deeper than the lower end of the pile 2.

Next, wire rope 1 is attached to stake 2 as shown in Figure 1(b).
6 and the wire loaf 16 is fixed to the wire fixture 13.

At this time, the means for connecting 716 at the wire port may be any method, such as pushing the wires 0-116 with a stick or the like after cutting the edge, or installing the rope 16 in advance in the casing gear 3. .

The other end of the wire row 116 is fixed by passing it through a sheave or the like that can stop the rotation at any time.

After connecting the stake 2 to the wire row 116 in this way,
When the casing auger 3 is rotated in the opposite direction as shown in FIG. 1 (C), the earth and sand discharged by edge cutting is guided from the outside of the casing auger 3 to the hole 17 in the auger 3, and the earth and sand in the hole 17 is consolidated. be and rise.

When the casing auger 3 rises due to reverse rotation, the piles 2 connected by the wire rope 16 also rise together and come out of the ground.

At this time, the earth and sand in the hole 17 is consolidated while being pressurized by the lower end of the pile 2, and gradually rises.

In this case, it is also possible to strengthen the ground by using soil from the outside of the casing auger 3 to backfill the holes 17 in the auger 3 with mortar with a poor mix.

After using the pile 2, remove the wire fixture 13 and take out the pile 2 from the inside of the casing auger 3 to complete the pile cutting work, and then use the auger 3 to remove the pile 2 as shown in Figure 1(d). The hole 17 thus formed is completely filled with earth and sand 18.

FIG. 5 shows another embodiment, and the difference from FIG. 1(a) is that a wire loaf 16 is connected to the pile 2, and a working machine other than the working machine of the casing auger 3, such as a crane 19, etc. It does not show the case where it is suspended and gradually pulled up.

In this case as well, in exactly the same way as above, first, the casing auger 3 is used to excavate deeper than the bottom end of the pile 2 and the side of the pile 2 is edged, and then the casing auger 3 is rotated in the opposite direction to raise the pile 2. Trim the bottom edge completely.

Next, the wire rope 16 is connected to the pile 2 and the crane 1
9 and pulled out by crane 19. At this time, the driving source for lifting the crane 19 holding the pile 2 and the driving source for lifting the casing auger 3 are separate, so if the lifting speed of the casing auger 3 is faster than the lifting speed of the pile 2. The earth and sand returned to the hole 17 in the auger 3 by the screw blade 14 in the casing auger 3 is returned to the pile 2.
The soil is pressed against the tip of the pile 2, slowing its rise, and the soil acts to push up the tip of the pile 2, resulting in more compaction.

Then, while returning the discharged earth and sand to the hole 17° in the same manner as described above, the casing auger 3 is reversed to compact the earth and sand in the hole 17, and the casing auger 3 is removed. In this case, the pile may be used first using a crane.

The casing auger 3 used in the pile method according to the present invention may have screw blades 10 on the outer periphery of the casing. For example, as shown in FIG. Feather 1
4 or in which the excavating blade 20 and screw blade 21 at the tip of the casing auger 3 face inward as shown in Fig. 4, the consolidation effect can be further enhanced, and the inner screw The blades apply an upper limit force to the pile when rotating in the forward direction, that is, when digging, and the reaction force is used to generate the driving force for the casing auger.
- [Effect of the invention] As explained above, the casing auger used in the pile method according to the present invention excavates when it rotates in the forward direction, and sends earth and sand below the casing auger when it rotates in the reverse direction, compacting the earth and sand in the hole in the casing auger. The fluidity of the earth and sand is brought to a high pressure state to give the pile an upward force, so the pile is pushed up from the lowest end, so even long piles can be handled easily, and there is no risk of breakage. After the pile is pulled out, the hole is filled with earth and sand, poorly mixed mortar, etc., so the strength of the ground does not decrease.In addition, the pile pulling and hole filling are done at the same time, making the work easier and reducing the work time. It has many effects such as being shortened.

[Brief explanation of the drawing]

Figure 1 shows the working process of the pile method according to the present invention, (a) is a cross-sectional view during edge cutting and digging work, (b) is a cross-sectional view while connecting the wire rope to the pile and wire fixture, ( C) is a cross-sectional view of the pile and casing auger being pulled up simultaneously;
d) is a cross-sectional view of the ground after pile removal work, Figure 2 is an external side view of each hole, Figure 3 is an enlarged view of the screw auger used in the method of the present invention, and Figure 4 is a diagram of the screw auger. In other embodiments, (a) and (b) are different cross-sectional views of the cut plane,
(C) is a plan view, and FIG. 5 is a sectional view of another embodiment of the construction method of the present invention. DESCRIPTION OF SYMBOLS 1... Ground, 2... Pile, 3... Casing auger, 10... Screw blade, 13... Wire fixture, 16... Wire rope, 19... Crane. Applicant's agent Kiyoshi Inomata b 1 Shiku G) (b) (c)
(d) Bi 3 Koku 54 Figure (0) (b) (C)

Claims (1)

[Claims] 1. After the pile and the ground around it are edge-trimmed over the entire length of the pile using a casing auger provided with screw blades around the hollow body, a wire rope is connected to the pile. Then, this wire rope is fixed by a wire fixing device above the casing auger, and then the casing auger is reversed and the earth and sand discharged by the edge cutting is backfilled from the outside of the casing auger, and the pile is fixed together with the casing auger. A pile extraction method characterized by the fact that the piles are pulled out. 2. In the pulling operation after completing the edge cutting of the pile, the pile is lifted with a work machine provided separately from the casing auger,
2. The pile extraction method according to claim 1, wherein the earth and sand discharged by the edge cutting is introduced into the hole by reversing the casing auger and is backfilled while being compacted.