JP2002322646A - Method and device for removing existing pile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for removing an existing pile at a low cost by building a casing around the existing pile for dissolving compaction of wrap around earth in the outer circumference part. SOLUTION: The casing 7 turned by an auger machine 6 is constructed of a lower casing 7a, in which a cutter is arranged in the tip while a screw 7as is arranged in the outer circumference, an upper casing 7b arranged above the lower casing, a casing 7c arranged above the upper casing 7b and having a screw 7cs, and a casing 7d arranged above the casing 7c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an existing pile, for example, a steel pipe pile or a PC pile (precast), which is buried in the ground after a building on the ground is destroyed when rebuilding a building or a factory. The present invention relates to a method for removing a concrete pile and a device used for the method.

[0002]

2. Description of the Related Art When a building on the ground is removed by redevelopment of a city or the like and a new building is to be built on the former site, an existing pile of a previous building becomes an obstacle.

[0003] Therefore, various proposals have been made as a method of removing the pile, and as one of the methods, a casing is press-fitted into an outer peripheral portion of an existing buried pile to cut off the pile and the ground, and then the pile is pulled out. The removal method is used. Japanese Patent Application Laid-Open (JP-A) No. 58-5 is a first technology group of the method.
Japanese Patent No. 41277, Japanese Patent Application Laid-Open No. 2000-144735, and Japanese Patent Publication No. 5-63576 describe, as a second technology group, Japanese Patent Application Laid-Open Nos. 2001-3362 and 2001-3363. There are things.

The first technology group uses a device in which a helical screw is attached to the outer peripheral portion of a casing over the entire length of the casing, and the second technology group uses a device in which a helical screw is mounted. A device attached to only the lower end of the outer peripheral portion of the casing is used.

[0005]

The first technology group has an excellent ability to discharge earth and sand around the outer periphery of the casing and has low excavation resistance. However, since the screw is attached over the entire length of the casing, there is a disadvantage that the cost is increased.

In the second technology group, since a spiral screw is provided only at the lower end of the casing, the cost is low, but there is a difficulty in discharging the earth and sand, and it becomes impossible to set up during construction. Sometimes. This is because only the lower end of the casing has a screw, so the excavated earth and sand guided by the screw can only be pushed up or moved upward by the earth and sand created from below above the screw (the part without the screw). This is because earth and sand having low fluidity, for example, sand and gravel, have a high resistance when moving upward, so that they are compacted, causing an increase in the rotational resistance of the casing. In particular, a problem is likely to occur when a long casing is installed. Even if it does not become impossible to construct, the excavation of the earth and sand excavated by the cutter at the tip of the casing is poor, so clogging occurs between the cutters,
There is a possibility that a situation where the casing does not enter even though the rotation resistance is low may occur.

SUMMARY OF THE INVENTION In view of the above problems, the present invention solves the consolidation state of earth and sand which has wrapped around the outer periphery of a casing, reduces the rotational resistance, enables the installation of a long casing, and reduces the manufacturing cost. It is an object of the present invention to provide a method for removing a pile and an apparatus therefor.

[0008]

According to a first aspect of the present invention, there is provided a method for removing an existing pile, comprising: a rotary drive; and an actuator for vertically moving the rotary drive. An elevating device comprising a guide, a lower casing having a plurality of cutters at a tip thereof, and a plurality of spiral screws provided on an outer peripheral surface, and an upper portion provided on an upper portion of the lower casing and connected to the rotary drive device A first casing consisting of a casing and a first casing, the first casing being rotationally press-fitted so as to surround an existing pile buried in the ground with a cutter at the tip of the first casing; A second casing having a plurality of spiral screws on an outer peripheral surface is connected to an upper casing of one casing, and the second casing is connected to the rotary drive device. And then press-fitted again, at least the first and second casings surrounded the existing pile around the entire length thereof to release the restraint of the existing pile from the ground, and the first and second casings were pulled out. Later, the existing piles will be removed.

According to a second aspect of the present invention, there is provided a rotary drive device, a lifting / lowering device comprising an actuator for vertically moving the rotary drive device and a guide, an upper end connected to the rotary drive device, and a plurality of lower ends provided at the lower end. A casing provided with a cutter, and provided with a plurality of helical screws intermittently provided at predetermined intervals on the outer peripheral surface thereof at predetermined intervals over the longitudinal direction thereof. Rotating press-fit so as to surround the periphery of the existing pile buried in, wrapping around the entire length of the existing pile with the casing over the entire length to release the constraint of the existing pile to the ground, and pulling out the casing after removing the casing. It is to be removed.

According to a third aspect of the present invention, high-pressure water is injected from a tip of the casing.

According to a fourth aspect of the present invention, an apparatus for removing an existing pile according to the present invention comprises a rotary drive, an actuator for moving the rotary drive up and down, and a guide. An elevating device, a lower casing provided with a plurality of cutters at the tip and provided with a plurality of spiral screws on the outer peripheral surface, and an upper casing provided at an upper portion of the lower casing and connected to the rotary drive device. It comprises a first casing and a second casing connected to an upper casing of the first casing and having a plurality of spiral screws on an outer peripheral surface.

According to a fifth aspect of the present invention, there is provided a rotary driving device, a lifting and lowering device including an actuator for vertically moving the rotary driving device and a guide, an upper end connected to the rotary driving device, and a lower end provided with a plurality of rotary driving devices. A casing provided with a cutter and provided with a plurality of spiral screws intermittently provided at predetermined intervals on an outer peripheral surface thereof in a longitudinal direction thereof.

According to a sixth aspect of the present invention, the rotary driving device comprises an auger machine, the actuator comprises a winch and a wire rope, and the guide comprises a reader and a guide rail of the reader.

According to a seventh aspect of the present invention, the casing includes:
It has a jet port for injecting high-pressure water from the lower end.

The invention according to claim 8 is the one in which a plurality of holes are formed in a portion of the casing other than where the screw is provided.

According to a ninth aspect of the present invention, a high-pressure water pipe is provided in a portion of the casing other than the portion where the screw is provided so as to be inclined in the rotation direction of the casing.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a method and an apparatus for removing an existing pile according to the present invention will be described with reference to FIGS. FIG. 1 is an overall view of an existing pile removing device, FIG. 2 is an enlarged top view of the removing device, and FIG. 3 is an explanatory diagram illustrating a method for removing an existing pile according to the present embodiment.

As shown in FIG. 1, the removing device is held in a vertical posture via a revolving unit 2 mounted on a traveling unit 1, a front frame 3 and a back stay 4 mounted on the revolving unit 2. A pile driving machine A including a leader 5 and a casing 7 described below which is moved up and down along the leader 5 of the pile driving machine A.
An auger machine 6 as a rotary drive device, and an excavator that is rotatably connected to a lower portion of the auger machine 6 and excavates around a pile 100 buried in the ground to cut an edge between the pile 100 and the ground. And a casing 7 to which a plurality of ground excavation cutters 11 are attached.

The auger machine 6 is supported by a guide rail 5a of the reader 5 so as to be able to move up and down, and is suspended by a wire rope 9 looped around a top sheave 8 attached to the top of the reader 5. The wire rope 9 is moved up and down along the leader 5 by winding or unwinding the wire rope 9 with a winch 10 provided on the revolving unit 2. Here, the casing 7 has a lower casing 7a in which a plurality of cutters 11 are attached to a lower end, and a plurality of spiral screws 7as attached to an outer peripheral side of a lower end, and an upper casing 7b without a screw, which is located above the lower casing 7a. Further, a casing 7c to which a plurality of spiral screws 7cs are attached is located above the casing 7c, and a casing provided with screws at intervals such as a casing 7d without a screw is located further above the casing 7c. .

Here, the lower casing 7a and the upper casing 7b constitute a first casing 7A, and the casing 7c and the casing 7d constitute a second casing 7B.

When the discharged soil has no fluidity or when the ground is hard, a high pressure is applied to a tip nozzle 13 (see FIG. 4) of the casing 7 through a swivel joint 12 attached between the casing 7 and the auger machine 6. Spout water. In the present embodiment, a pipe (not shown) of high-pressure water is mounted vertically in the casing 7b without a screw. Reference numeral 12a denotes a detent for the swivel joint 12, which moves up and down along the guide rail 5a.

Next, a method of removing the existing pile 100 using the removal device having the above-described configuration will be described with reference to FIG.

First, when the wire rope 9 of the winch 10 provided on the revolving unit 2 is drawn out, the auger machine 6 suspended by the wire rope 9, the swivel joint 12,
The first casing 7A descends. When the tip of the first casing 7A descends to a position where it contacts the ground, the auger machine 6
The first casing 7A is rotated by the drive of, and the ground is excavated by the cutter 11 attached to the tip. At this stage, due to the length of the reader 5, the second casing 7B with the screw 7cs is not yet attached to the first casing 7A, and only the first casing 7A is in a state. Then, as shown in FIG. 3A, the first casing 7A is excavated and lowered so as to surround the periphery of the existing pile 100. At this time, the earth and sand created by the excavation is discharged to the inner peripheral side and the outer peripheral side of the first casing 7A. The earth and sand discharged to the outer peripheral side is guided by the spiral screw 7as and moves upward. As the first casing 7A digs, the amount of earth and sand increases, and the earth and sand on the outer peripheral side is sequentially sent upward.
However, the soil gradually moves upward due to the consolidation, so that the soil cannot move smoothly. Therefore, the cutter 11 attached to the tip of the first casing 7A is in a clogged state, and the excavation efficiency is significantly reduced. When this occurs, as shown in FIG. 3B, the second casing 7B with the screw 7cs is connected. When the second casing 7B is excavated and lowered in this state, the compacted earth and sand on the outer peripheral portion of the second casing 7B near the ground can be rubbed and loosened by the screw 7cs. Further, when the entire casings 7A and 7B are raised and lowered, soil and sand above the outer peripheral side of the lower casing 7a can be loosened. Through such a process, the process finally reaches FIG. Then the casing 7A, 7B
If the existing pile 100 is a steel pipe pile, it is pulled out with a vibro hammer.

In the case where the ground is not fluid, such as a gravel layer, a high-pressure water generator (not shown) separately installed on the ground
The high-pressure water is supplied from a hose 14a through a hose 14a, and is discharged from a nozzle 13 at the tip of the lower casing 7a via a swivel joint 12 and a pipe 14b disposed in the casing 7. The pipe 14b of the casing 7 is vertically arranged where there is no screw, and is disposed along the lower surface of the screw where there is a screw.

As a result, the ground excavated by the cutter 11 is loosened, and not only the excavation resistance is reduced, but also the excavated earth and sand is fluidized and the mobility is improved. When the casing 7 is installed at a large depth where the casing 7 is long, the movement resistance of the earth and sand on the outer peripheral side also increases, so that the earth and sand on the outer peripheral side of the casing 7 is gradually compacted. However, when the soil reaches the casing 7cs with the upper screw, the compacted soil is loosened and forcibly discharged upward.

In the above-described embodiment, the second casing 7B is connected to the upper portion of the first casing 7A. However, depending on the length (excavation depth) of the existing pile 100, the second casing 7B The second casing 7B may be further added to the upper part, and the first casing 7A may be replaced with a lower casing 7a, an upper casing 7b, and a casing 7A.
c, 7d.

Next, a second embodiment will be described with reference to FIGS. FIG. 4 is a partially enlarged view of a casing 70 according to the second embodiment, and FIG. 5 is a sectional view taken along line aa of FIG.

The components having the same structure as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

In the drawing, a casing 70a has a plurality of cutters 11 attached to the lower end thereof and a plurality of spiral screws 7as attached to the outer peripheral side of the lower end.
And a screwless casing 70b positioned above it, a casing 70c further mounted with a plurality of spiral screws 7cs, and a screwless casing 7 positioned further above
As shown by d, it is composed of a casing provided with several screws intermittently at predetermined intervals.

A high-pressure water pipe 140b is provided between the screw 7as and the screw 7cs of the casing 70, and the pipe 140b is a pipe 14b of the above-described embodiment.
Unlike the case b, the casing 70 is attached such that the upper part is delayed with respect to the lower part when the casing 70 is rotated, that is, when the casing 70 is rotated. The pipe 140b is protected by a protective material 150 such as an angle material. The nozzle 13 at the tip of the casing 70a has the same structure as the casing 7.
In the place where the screw of the casing 70 is not provided, the hole 70
e are drilled at intervals.

Next, a situation in which the casing 70 is erected using the casing 70 having the above configuration will be described. Excavation is performed by the cutter 11 attached to the tip of the casing 70a, and the excavated earth and sand is discharged above the outer peripheral portion of the casing 70, as in the case of the casing 7 described above. Here, the casing 70b
Is moved upward while being compacted. However, the earth and sand reaching the hole 70e formed in the casing 70b passes through the casing 70 through the hole 70e.
b can be moved from the outer circumference to the inner circumference or from the inner circumference to the outer circumference. That is, since the rotational resistance of the casing 70 is the sum of the respective resistances on the outer peripheral side and the inner peripheral side, the holes 70e balance the earth and sand discharge resistance on the outer peripheral side and the inner peripheral side, and the rotational resistance on one side becomes extremely high. Can be prevented. Further, since the protection member 150 of the pipe 140b is attached at an angle, the effect of stirring the earth and sand and the rotation resistance can be reduced. Casing 70
When the casing 70b is pulled out, the inside of the casing is in a vacuum state and the pulling resistance is increased.
Since the holes are provided, the vacuum state can be prevented.

In this embodiment, the first casing can be constituted by the casing 70a and the casing 70b, and the second casing can be constituted by the casing 70c and the casing 70d.

In the above-described embodiment, the removal device in which the casings 7 and 70 are attached to the pile driving machine A has been described. However, the all-casing construction machine described in Japanese Patent Application Laid-Open No. 2000-144735 has Can be attached to form a removal device.

[0034]

As described above, in the method for removing an existing pile according to the present invention, the casing is mounted on the ground by providing a screw at a distance from the lower end portion of the outer periphery of the long casing and above. When the rotary press-fitting is performed, the earth and sand guided to the outer peripheral side of the casing among the earth and sand generated by the cutter is not compacted upward, so that clogging of the cutter and rotation resistance of the casing can be reduced. Further, the cost can be reduced as compared with the case where the screw is provided over the entire length of the casing.

In addition to the above-described casing structure, by injecting high-pressure water from the nozzle at the tip of the casing, clogging of the cutter and rotational resistance of the casing can be further reduced.

Further, in the apparatus for removing an existing pile according to the present invention, a removing method having the above-mentioned effects can be realized. By inclining the water pipe in the rotation direction, it is possible to balance the rotational resistance between the outer peripheral side and the inner peripheral side of the casing, to prevent vacuum inside the casing when the casing is pulled out, and to reduce the pulling force.

[Brief description of the drawings]

FIG. 1 is an overall view of an existing pile removing device according to a first embodiment of the present invention.

FIG. 2 is an enlarged side view of the upper part of the removing device in FIG.

FIG. 3 is an explanatory view showing a method for removing an existing pile using the existing pile removing device of the present invention.

FIG. 4 is a configuration diagram of a casing in a second embodiment of the existing pile removal device of the present invention.

FIG. 5 is a sectional view taken along line aa of FIG. 4;

[Explanation of symbols]

 6; Auger machine 7, 70; Casing 7a; Lower casing 7b; Upper casing 7c, 7d, 70a to 70d; Casing 7as, 7cs; Screw 7A; First casing 7B; Second casing 11; Cutter 13; Tip nozzle 14b; 140b; piping 70e; hole 100; existing pile A; pile driver

Continued on the front page (72) Inventor Hiroshi Kusumi 2-5-1 Koraku, Bunkyo-ku, Tokyo F-term in Hitachi Construction Machinery Co., Ltd. (reference) 2D050 AA03 AA06 AA07 AA16 CB23 DA03 DA05 DB05

Claims (9)

[Claims] 1. A rotary driving device, a lifting and lowering device including an actuator for vertically moving the rotary driving device and a guide, a plurality of cutters at a tip, and a plurality of spiral screws provided on an outer peripheral surface. Buried in the ground with a cutter at the tip of the first casing, using a device composed of a lower casing that is provided and an upper casing provided on the lower casing and connected to the rotary drive device. The first casing is rotationally press-fitted so as to surround the circumference of the existing pile, and a second casing having a plurality of spiral screws on an outer peripheral surface is connected to an upper casing of the first casing. (2) The casing is connected to the rotation drive device and rotationally press-fitted again, and at least the first and second casings cover the entire circumference of the existing pile over the entire length. A method for removing an existing pile, wherein the existing pile is released after removing the first and second casings by surrounding the existing pile to release the restraint from the ground. 2. A rotary driving device, a lifting and lowering device comprising an actuator for raising and lowering the rotary driving device up and down, and a guide; an upper end connected to the rotary driving device; A casing provided with a plurality of helical screws intermittently provided at predetermined intervals over the surface in a longitudinal direction thereof, using an existing device embedded in the ground with a cutter at the tip of the casing. It is characterized by rotating press-fitting so as to surround the periphery of the pile, surrounding the existing pile with the casing over its entire length to release the constraint on the ground of the existing pile, and removing the existing pile after removing the casing. How to remove existing piles. 3. The method for removing an existing pile according to claim 1, wherein high-pressure water is injected from a tip of the casing. 4. A rotary drive device, a lift device comprising an actuator for raising and lowering the rotary drive device up and down, and a guide, a plurality of cutters provided at a tip, and a plurality of spiral screws provided on an outer peripheral surface. A first casing comprising a lower casing, an upper casing provided on an upper portion of the lower casing and connected to the rotary drive device, and a plurality of spiral-shaped outer peripheral surfaces connected to the upper casing of the first casing. An apparatus for removing an existing pile, comprising: a second casing having a screw. 5. A rotary driving device, a lifting and lowering device comprising an actuator for raising and lowering the rotary driving device up and down, and a guide; an upper end connected to the rotary driving device; A casing provided with a plurality of spiral screws intermittently provided at predetermined intervals on a surface thereof in a longitudinal direction thereof. 6. The removal device for an existing pile according to claim 4, wherein the rotary drive device comprises an auger machine, the actuator comprises a winch and a wire rope, and the guide comprises a leader and a guide for the leader. An existing pile removal device comprising a rail. 7. The existing pile removing device according to claim 3, wherein said casing is provided with a spout for injecting high-pressure water from a lower end. Removal equipment. 8. The existing pile removing device according to claim 3, wherein a plurality of holes are formed in the casing at positions other than where the screws are provided. Pile removal equipment. 9. The removal device for an existing pile according to claim 7, wherein a high-pressure water pipe is provided at a portion of the casing other than where the screw is provided so as to be inclined in a rotation direction of the casing. Removal equipment for existing piles.