JP2003301459A - Method and device for removing existing pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device, which reduce noise and vibrations and allow the efficient removal of an existing pile. <P>SOLUTION: The existing pile 9 is removed by means of a hammer glove 31 while being crushed by erecting a casing tube 5 by a rotary press-in device 1 for being generally used for an all-casing construction method. In the method and the device, the casing tube 5 is erected so that the existing pile 9 can be deviated from a center of the casing tube 5. A falling and folding device is fixed to a lower end of a grip mechanism 10 for locking a driving rod 20, whose lower end is equipped with a falling and folding blade 21, to an inner peripheral surface of the casing tube 5. The falling and folding device is suspended by a crane so as to be inserted into the casing tube 5. Subsequently, the blade 21 is rotated by being pressed into the central part of the casing tube 5 by the device 1, so that the existing pile 9 can be made to fall and folded. The fallen and folded existing pile 9 is discharged by means of the hammer glove 31. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing an existing pile, and more particularly to a method for installing and removing a casing tube so as to surround the existing pile.

[0002]

2. Description of the Related Art In construction such as redevelopment of urban areas and replacement of bridges, generally, concrete piles or steel pipe piles are constructed by building a casing tube around an existing pile with a rotary press-fitting device used in the all-casing method. The existing piles have been removed.

In this method, as shown in FIG. 5, a casing tube is built so as to surround an existing pile, a hammer mug 41 suspended from a crawler crane 40 is dropped to crush the existing pile, and the fragments are discharged together with earth and sand. is doing. However, in the case of this method, it takes time to crush the existing piles and it may be difficult to crush them. Therefore, generally, a heavy weight (chisel) is hung on the crawler crane 40 and dropped to drop the existing piles. It is crushed and discharged at the hammer mug 41.

[0004]

However, in such a conventional means, since a ton of chisel of several tons is allowed to fall freely on the existing pile, a large shock or vibration is generated and noise is a problem. In addition, when the existing pile has a reinforcing bar, the reinforcing bar may be entangled with the hammer mug when discharged by the hammer mug, or the shell of the hammer mag may be caught between the existing pile and the casing tube, so that the hammer mag cannot be pulled up.

Therefore, an object of the present invention is to provide a method and apparatus for removing existing piles efficiently with less noise and vibration.

[0006]

In order to achieve the above object, the present invention employs the following means. That is, in a method of installing a casing tube with a rotary press-fitting device so as to surround the existing pile and removing the existing pile, after installing the casing tube so that the existing pile is off the center, the bottom end is provided with a folding blade. The folding device fixed to the lower end of the grip mechanism that locks the drive rod with the inner peripheral surface of the casing tube is hung by a crane and inserted into the casing tube, and the folding blade is press-fitted with a rotary press-fitting device. The feature is that the existing piles that have been folded are discharged by a hammer mug.

According to the present invention, an existing pile is collapsed to a proper length by a folding device and removed. Since the collapsed blades are pressed into the center of the casing tube, the existing piles should not be located in the center when installing the casing tube.

The folding device has a grip mechanism to which a drive rod having folding blades is fixed. The structure of the grip mechanism is not particularly limited as long as it can be locked to the inner peripheral surface of the casing tube. In addition, the folding blade must be shaped so that it can be easily pressed into the ground.

A specific structure of the folding device is, as described in claim 3, a grip mechanism which expands in a radial direction and engages with an inner peripheral surface of a casing tube, and a grip mechanism attached to a lower end of the grip mechanism. Therefore, it is desirable that the drive rod has a plurality of folding blades protruding in the radial direction of the casing tube and tapering in the lower end direction.

The folding blades are provided symmetrically on the drive rod. Generally, two sheets should be provided in the direction of 180 degrees, but when there are three existing piles, three sheets are provided every 120 degrees. When the existing pile is folded down, the drive rod is bent and easily tilted. When the drive rod tilts, the pressure contact force between the pressure contact member of the grip mechanism and the inner peripheral surface of the casing tube becomes small, and slippage occurs.

Therefore, as described in claim 4, it is preferable that a stabilizer having an inner diameter of the casing tube and a slight gap is fixedly provided on the upper side and the lower side of the grip mechanism to limit the inclination of the drive rod. Further, when the earth and sand are hard, the resistance at the time of press-fitting the folding blade is large, so it is desirable to loosen the earth and sand around the existing piles in advance. This means is a casing tube having spiral ribs attached to the inner peripheral surface thereof, as described in claim 2, and is built up by a rotary press-fitting device before press-fitting the folding blade to dust the surrounding earth and sand. Good. Moreover, it is advisable to press fit the casing tube while swinging it in small steps. Furthermore, if an excavation bit is attached to the lower end of the folding blade, press fitting becomes easier.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. First, an apparatus for carrying out the method for removing an existing pile will be described. FIG. 1 shows the entire structure of a device for removing an existing pile, and shows a state in which a casing tube 5 is built by a rotary press-fitting device 1 and a folding device is press-fitted into the casing tube 5.

The rotary press-fitting device 1 includes an elevating frame 2 connected to elevating cylinders 4 provided at four corners of a base frame 3.
The lifting frame 2 is provided with a casing tube 5
A rotating frame having a tapered hole through which is inserted is rotatably supported. A chuck cylinder connected to the upper frame 7 inserts a wedge member between the casing tube and the tapered hole to fasten the rotating frame and the casing tube 5.

In the installation, the casing tube 5 is held in the ground while being rotated by the motor 8 while the casing tube 5 is being held by the rotating frame, and the elevating cylinder 4 is lowered to rotate the casing tube 5 while rotating it. The casing tube 5 has a drill bit 5a fixed to the lower end thereof, and a spiral rib 5b attached to the inner periphery of the lower part thereof.

The folding device comprises a grip mechanism 10 and a drive rod 20 having a folding wing 21 fixed to the lower portion thereof. The upper end of the drive rod 20 is fixed to the lower end of the grip mechanism 10. The folding device is suspended by the crawler crane 30 via the swivel joint 27. 2
5 is a joint and 26 is a swivel link.

The grip mechanism 10 is, as shown in FIG.
An upper connecting member 12 in which a shaft 11 is fixedly mounted on a lower portion, a lower connecting member 13 into which the shaft 11 is slidably fitted, a plurality of pressure contact members 14 in pressure contact with the inner peripheral surface of the casing tube 5, and an upper connecting member. It is composed of links 15a, 15b and 15c for connecting the material 12 and the lower connecting material 13 to the pressure contact member 14. 2 shows a state where the pressure contact member 14 is locked to the inner peripheral surface of the casing tube 5 in the left half and a state where the pressure contact member 14 is separated from the inner peripheral surface of the casing tube 5 in the right half. Shows.

The link 15a is attached so as to be inclined downward from the upper connecting member 12, and the links 15b and 15c are attached so as to be inclined upward from the lower connecting member 13.
A joint 25 is fixed to the upper end of the upper connecting member 12, and is connected to a swivel joint 27 via a swivel link 26. Further, a stabilizer 18a having blades having a slight gap with the inner peripheral surface of the casing tube 5 fixed to four positions on the circumference is attached to the side of the upper end of the upper connecting member 12. Further, a flange 13a for mounting the drive rod 20 is fixedly provided on the bottom of the lower connecting member 13.

The driving rod 20 has a cylindrical shape, and the upper end of the flange 2 is attached to the flange 13 of the grip mechanism 10.
0a, and the folding blade 21 is fixed to the lower part. Reference numeral 18b is a stabilizer, which is similar to the stabilizer 18a. Two folding wings 21 are provided symmetrically,
In this embodiment, they are integrated and have a substantially rhombic shape as a whole. The lower end portion has a shape that is pointed downward. Further, a plurality of mounting holes 21 a for fixing the excavation bit 22 are provided at the lower end of the folding blade 21.

When the folding device is suspended in the casing tube 5, the lower connecting member 1 of the grip mechanism 10 is used.
3, the weights of the drive rod 20 and the folding blades 21 open the space between the upper connecting member 12 and the lower connecting member 13,
Since the inclination angles of 5a to 15c are increased, the pressure contact member 14
Is in a reduced state (state on the right side of FIG. 2). Therefore, the inside of the casing tube 5 can be freely moved up and down.

When the folding device is grounded at the bottom of the hole, the upper connecting member 12 is lowered by its own weight to reduce the distance between the upper connecting member 12 and the lower connecting member 13 as shown on the left side of FIG.
The pressure contact member 14 is expanded so that 5a to 15c become horizontal. As a result, the pressure contact member 14 is in pressure contact with the inner peripheral surface of the casing tube 5.

Next, a method of removing the existing pile by the device constructed as described above will be described with reference to FIG. First, the rotary press-fitting device 1 is installed at a position where the existing pile 9 is buried. In this case, the existing pile 9 should not be located at the center of the casing tube 5. When there are multiple existing piles 9, the casing tube 5 is placed in the center between the existing piles 9.
Position the center of.

For example, in the case where there are two existing piles 9, FIG.
As shown in (a), set the center of the casing tube 5 to 2
It is installed so as to be located in the center between the existing piles 9 of the book. Then, the casing tube 5 is pushed in while being rotated by the rotary press-fitting device 1. At this time, the earth and sand in the casing tube 5 are loosened by the spiral rib 5b attached to the lower portion of the casing tube 5.

After the casing tube 5 is built once deep in the ground, it is pulled up to near the upper end of the existing pile 9. Next, Hammaglab 3 hung on a crawler crane
1 is inserted into the casing tube 5, and as shown in FIG. 4B, the earth and sand are discharged until the head of the existing pile 9 comes out.

Next, the folding device is suspended by the crawler crane, inserted into the casing tube 5, and lowered so that the direction of the folding blades 21 is substantially perpendicular to the existing piles 9. When the tip of the folding blade 21 comes into contact with the ground, the pressure contact member 14 of the grip mechanism 10 expands and comes into pressure contact with the inner peripheral surface of the casing tube 5.

Next, the tubing device 1 press-fits the casing tube 5 onto the existing pile 9 while swinging it in small steps at an angle within a range where the folding blades 21 do not hit. The folding wings 21 are
As shown in FIG. 4C, the casing tube 5 is integrated with the casing tube 5 to loosen the earth and sand and push it in while loosening it. When the ground is hard, a plurality of excavation bits 22 are attached to the lower end of the folding blade 21.

When the excavation blade 21 is pushed to an appropriate depth, the press-fitting of the casing tube 5 is stopped and the casing tube 5 is gradually rocked at a large angle. As a result, the folding blade 21 comes into contact with the existing pile 9 and makes it fall. Finally, by rotating the entire circumference, the reinforcing bars and the like inside the existing pile 9 can be completely cut.

When the folding blade 21 is rotated, the drive rod 20 tends to incline due to the resistance of the earth and sand or the existing pile 9, but it is restricted by the stabilizers 18a and 18b.
Therefore, the pressure contact force of the pressure contact member 14 locked to the inner peripheral surface of the casing tube 5 is prevented from weakening.

Next, as shown in FIG. 4D, the folding device is pulled up to suspend the hammer mug 31, and the folded existing pile 9 is discharged together with the earth and sand. After discharging the existing piles and soil for the length of the casing tube 5,
The casing tube 5 is added to the upper end of the casing tube 5, and the above work is repeated to remove the entire existing pile 9.

[0029]

As described above, according to the existing pile removing apparatus of the present invention, the casing tube is installed so that the existing pile is displaced from the center, and then the drive rod having the folding blade at the lower end is mounted on the casing tube. The folding device, which is fixed to the lower end of the grip mechanism that locks to the inner peripheral surface of the, is hung by a crane and inserted into the casing tube. Since the piles are folded and the existing piles that have been folded are discharged by the hammer mug, the existing piles can be cut and removed with a certain length, and work efficiency is good. Moreover, it is particularly effective for removing existing piles in urban areas without generating noise as in the conventional method in which existing piles are crushed by a chisel and discharged by a hammer mug.

[Brief description of drawings]

FIG. 1 is an overall view of an apparatus for implementing an existing pile removing method of the present invention.

FIG. 2 is a side view showing details of the grip mechanism.

FIG. 3 shows the details of the same folding wing, where (a) is a front view and (b) is a side view.

FIG. 4 is a state diagram showing a method for removing the existing pile.

FIG. 5 is a schematic diagram showing a state in which existing piles are removed by a conventional crawler crane equipped with a grab hammer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating press-fitting device 2 ... Elevating frame 3 ... Base frame 4 ... Elevating cylinder 5 ... Casing tube 5a ... Excavation bit 5b ... Rib 7 ... Upper frame 8 ... Motor 9 ... Existing pile 10 ... Grip mechanism 11 ... Shaft 12 ... Top connection Material 13 ... Lower connecting material 13a ... Flange 14 ... Press contact member 15a ... Link 15b, 15c ... Link 18a, 18b ... Stabilizer 20 ... Drive rod 20a ... Flange 21 ... Folding blade 21a ... Mounting hole 22 ... Drilling bit 25 ... Joint 26 Swivel link 27 Swivel joint 30 Crawler crane 31 Hammaglab

Claims (4)

[Claims] 1. A method of removing a pre-existing pile by installing a casing tube with a rotary press-fitting device so as to surround the pre-existing pile. A folding device fixed to the lower end of a grip mechanism that locks a drive rod equipped with blades on the inner peripheral surface of a casing tube is suspended by a crane and inserted into the casing tube, and the folding blades are rotated and press-fitted. A method for removing existing piles, which comprises press-fitting and rotating the piles to collapse the existing piles and discharging the collapsed existing piles with a hammer mug. 2. A spiral rib for loosening earth and sand is attached to the inner peripheral surface of the casing tube, and the rib is installed by a rotary press-fitting device before press-fitting the folding blade. How to remove existing piles. 3. A grip mechanism which expands in the radial direction and engages with the inner peripheral surface of the casing tube, and a plurality of grip mechanisms which are attached to the lower end of the grip mechanism and project in the radial direction of the casing tube and whose lower end direction is tapered. The folding device for performing the method for removing an existing pile according to claim 1, characterized in that it comprises a driving rod having a folding blade fixed to a lower end thereof. 4. The folding device according to claim 3, wherein stabilizers having a slight gap with the inner peripheral surface of the casing tube are fixedly provided on the upper side and the lower side of the grip mechanism.