JP2001226967A - Pull-out pretreatment method for embedded pile and equipment therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently remove a pile in response to the state of driving of a pile by excavating the vicinity of the pile with an excavating casing with a cutter and, at the same time, excavating the surroundings with a screw auger and then excavating the vicinity of the target pile. SOLUTION: By using two-shaft drive type earth auger machine 20, an excavating casing 4 equipped with a cutter 4d capable of excavating the vicinity of a target pile A is attached to tip of one of the shafts, an auger screw 5 is arranged to the other shaft, ground in the vicinity of a pile A is cut by the excavation casing 4, at the same time, excavation and earth removal are performed by an adjacent auger screw 5, the vicinity of the pile A is excavated to the required depth thereby making the pull-out of the pile A easier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pre-pulling pre-pulling method for buried piles which can be efficiently pulled out and removed during foundation work or the like of a building and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, a large number of foundation piles have been driven into a building in order to strengthen the foundation thereof. Prefabricated piles such as concrete piles are mainly used as such foundation piles. However, in order to construct a new building by dismantling and removing an old building due to aging of the building, remodeling of the city area, or zoning, etc., or constructing a large building, the foundation pile of the old building was constructed. Hinders Therefore, it is necessary to remove old foundation piles.

In order to remove such a pile, unlike at the time of driving the pile, it is necessary to overcome the earth pressure acting on the pile and to remove the pile, so that a large operating force is required. Therefore, conventionally, as shown in FIG. 3, for example, after excavating a large number of holes 50 around a buried foundation pile A to expose the head a of the pile A, the pile A is exposed. A chain or a wire rope is wound around the head part a, and a part thereof is pulled up by a lifting machine (for example, a crawler crane) to pull out the pile.

[0004] Alternatively, a casing provided with a number of cutters at a tip capable of excavating around the pile is rotated to excavate around the pile to loosen it, exposing the pile head, and then using a wire rope or the like as in the above example. A method of tying the exposed head of a pile and pulling it out with a crane is also used.

[0005]

However, in the above-described method of excavating a large number of holes around the pile to expose the head of the pile, the above-mentioned method of processing is performed in the ground acting on the pile. There is a problem that the side pressure is large, a large force must be applied to the drawing, and the preparation requires a lot of trouble and labor, resulting in poor working efficiency.

Furthermore, in places where the ground is soft or where the foundation has been firmly finished, the used foundation pile is deeply driven. For this reason, if a large number of holes are drilled around the pile to extract the pile, more work and a very strong pulling force are required, and the workability is further reduced. Therefore, there is a problem that the construction period required for removing the piles is prolonged and the construction cost is increased, which impairs economic efficiency.

Also, in the method of excavating around the pile with a casing with a cutter and loosening the pile before pulling it out, it is difficult to excavate too deep due to high resistance during excavation. Since the workability is low and a lot of labor is required, a lot of costs are required, and there is a problem that economic efficiency is impaired and this is not preferable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to excavate around a pile to be removed with a drilling casing with a cutter and at the same time to excavate the vicinity with a screw auger. An object of the present invention is to provide a method for pre-pulling pre-pulling of buried piles and a device for excavating around the piles and efficiently removing the piles according to the driving state of the piles.

[0009]

Means for Solving the Problems and Functions / Effects In order to achieve the above-mentioned object, a method for pre-treating a buried pile according to the first invention uses a two-shaft driven earth auger machine. At the same time, drilling is performed by cutting around the target pile with a drilling casing equipped with a cutter at the tip attached to one axis and excavating and excavating with an auger screw attached to the other adjacent axis. It is characterized by excavating and facilitating pulling out of a pile.

According to the method of the present invention for pre-pulling a buried pile, an earth auger is installed such that a drilling casing is positioned around a pile to be removed, and the ground is drilled around the pile by the drilling casing. At the same time as cutting, when the auger screw is dug into the ground at the adjacent position,
The auger screw that excavates and rotates at the adjacent position excavates the excavated soil cut by the excavated casing, thereby facilitating excavation, increasing the excavation speed, and positively performing the excavated soil. Therefore, it is possible to excavate to a deep position to reduce the earth pressure acting on the pile. Therefore, if the earth auger machine is moved to another position after the excavation process, the pile can be easily removed without requiring a strong pulling force for the pile pulling operation by the crane or the like. In addition, there is an advantage that the processing can be performed without applying an extra external force such as vibration, so that there is no possibility of generating pollution. Naturally, there is also an effect that the construction period can be shortened and the construction cost can be reduced.

In the excavation by the excavating casing and the auger screw, the excavation by the auger screw may be advanced to perform the excavation. This has the effect of stabilizing the cutting posture of the excavation casing with respect to the ground, and enabling the auger screw to quickly excavate and discharge the excavated soil by the cutter at the tip of the excavation casing, thereby promoting the effect of promoting the work.

Next, a digging apparatus for pre-pulling of a buried pile according to a second invention applied to carrying out the first invention is provided with a tip at one end of a two-axis driving device of an earth auger machine. An excavating casing equipped with a cutter and capable of excavating around the pile is attached, and an auger screw is connected to the other axis, and the excavating casing and the auger screw can keep their axes parallel to each other near the tip. The auger screw is provided with a stop, and the tip of the auger screw is set to be longer so that advanced drilling can be performed from the drilling casing.

According to the present invention, there is provided an excavating apparatus for pre-pulling of a buried pile, wherein an auger screw and an excavator are provided which guide a driving device vertically along a leader of an earth auger machine and which are respectively attached to two shafts connected to the driving device. By driving the casing and surrounding the pile in which the excavating casing is buried, excavation is first started to the adjacent part of the pile by the tip cutter of the auger screw, so that the tip of this auger screw leads. After the excavation is started, the excavation casing is used to excavate the periphery of the pile while excavating. By doing so, the excavated portion of the excavated casing is guided to the portion excavated by the auger screw to positively discharge the soil, so that the pile can be cut and excavated around the pile without difficulty.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, referring to the drawings, a concrete embodiment of a method for pre-pulling of a buried pile according to the first invention based on a drilling device for pre-pulling of a buried pile to be carried out will be described. It will be explained while doing.

FIG. 1 shows an embodiment of an excavating apparatus used in a pre-pulling method of a buried pile.

The excavator 1 is driven biaxially by a drive unit 2 of an earth auger machine having a well-known structure, and can be guided up and down by a leader supported by a base machine (not shown). An excavating casing 4 having an aperture capable of receiving a target buried pile and an auger screw 5 are connected in parallel to output shafts 3a and 3b of a two-shaft power distribution device 3 directly connected to the two, and both rotate simultaneously. It is made to be driven.

The excavating casing 4 is configured such that an intermediate casing 4b having the same diameter can be connected to a base casing 4a connected to one output shaft 3a of the biaxial power distribution device 3 by a joint 6a at a top thereof. Casing 4
A plurality of cutters 4d are distributed and provided at the tip of c, and the cutter 4d at the tip cuts the ground around the pile A to excavate. For connection of the intermediate casing 4b, for example, as shown in the figure, a hook-shaped notch 4e is provided at one end of the casing, and a projection 4f engaging with the hook-shaped notch 4e is provided at the other end. At the connection portion, the protrusion 4f of the other casing is engaged with the notch 4e of the other casing to rotate in the anti-rotation direction, and then the stopper 4g is provided to sequentially connect and excavate to a deep portion. Have been able to.

In the vicinity of the cutter 4d at the tip end of the excavating casing 4, the output shaft 3a of the two-shaft power distribution device 3 passes through the input shaft 4s connected via the joint 6a and extends along the outer surface. A water supply pipe 7 is provided. An appropriate amount of water is supplied to the cutting portion by the water supply pipe 7 to facilitate excavation. In addition, the water supply pipe 7 having a predetermined length is previously attached to the side surface of the intermediate casing 4b, and is connected by a hose 7a at a connecting point.

The auger screw 5 is connected to the other output shaft 3b of the two-shaft power distribution device 3 by a joint 6b so as to rotate in the same direction as the excavating casing 4, and a screw cutter 5b is connected to the tip. The screw cutter 5 b is configured to be longer than the tip of the excavating casing 4. The screw auger 5 is connected at an intermediate portion by a well-known means like a conventional one, so that it can be excavated to a required depth. The shaft 5a of the auger screw 5 is formed as a hollow shaft so that water can be supplied to the distal end of the screw cutter 5b at the distal end, and water is supplied from the output shaft 3b of the two-shaft power distribution device 3 through the joint through the inside thereof. It has become.

The excavating casing 4 and the auger screw 5 are configured so that their axes are held in parallel by a steadying mechanism 8 at the distal ends thereof.
As the steadying mechanism 8, for example, a rotatable receiving portion 8a is provided on the outer periphery of the tip excavating casing 4c, and is wound around the shaft portion 5a of the auger screw 5 and is wound around the receiving portion 8a of the tip excavating casing 4c. A band-shaped supporting member 8b is used which is connected at a middle portion between the supporting members by a bolt 8c or the like and can be shaped. Note that the steady rest mechanism 8 is formed so as to be bulky so as not to hinder the excavation during excavation. Reference numeral 9 in the figure denotes internal pressure release in the excavating casing 4. Reference numeral 10 denotes a rotating mechanism for changing the directions of the two axes, which is rotated around the output shaft of the driving device 2 by a worm speed reducer so that the directions of the excavating casing 4 and the auger screw 5 can be changed.

In order to perform a pre-processing operation for pulling out the buried pile A using the excavating apparatus 1 configured as described above, as shown in FIG. , The base machine 2 of the well-known earth auger machine 20
The excavator 1 guided and supported by the leader 22 is attached to the lower part of the driving device 2 guided by the leader 22 by installing the leader 22 supported by the leader 1 at a position near the embedded pile A to be pulled out. The excavating casing 4 suspended by operating the rotating mechanism 10 is set at a position where the buried pile A can be fitted.

Next, the drive unit 2 is activated, and the excavating casing 4 and the auger screw 5 are rotated to contact the excavated ground. Then, since the auger screw 5 is longer than the tip of the excavating casing 4, the screw cutter 5b at the tip thereof excavates the ground first and leads. When the screw cutter 5b of the auger screw 5 slightly excavates and digs the ground, the cutter 4d at the tip of the excavating casing 4 excavates the ground and cuts around the pile A. It should be noted that the wire rope 23 suspending the driving device 2 is gradually extended by operating the hoist 24 as the excavation is promoted, and the driving device 2 is lowered.

When the excavation is started in this way, water is supplied to the excavation casing 4 and the excavation portion of the auger screw 5 through the respective water supply pipes so that the excavation conditions of the screw cutters 5b and 4d are improved. As the excavation progresses, the excavation portion on the excavation casing 4 side and the excavation portion formed by the auger screw 5 are adjacent to each other, so that both excavation portions communicate with each other at the adjacent portion.
Then, the excavated soil on the side of the excavating casing 4 which is not provided with the positive soil discharging means is retained. However, the auger screw 5 which discharges the excavated earth upward by the screw blades is subjected to advanced excavation. Since the excavated soil is discharged first to create a gap in the communication portion, the excavated soil on the side of the excavating casing 4 is sent out through the communication portion, so that the auger screw 5 functions to assist the discharge of the excavated soil. As a result, it is possible to promote the excavation of the excavating casing 4 and increase the efficiency.

When the periphery of the pile A, which has been dug to the required depth and is buried, is exposed, the excavation is stopped and the driving device 2 is operated together with the drive unit 2 to move the excavating casing 4 and the auger screw 5 on the ground. Then, the base machine 21 is operated to move to the next pile processing position.

In this way, the buried pile A is largely exposed, and in the next pile removal operation, a wire rope or a chain is wound around the pile head, and a lifting device such as a crane is used. Use a heavy machine to pull up and remove. At this time, since the pile A buried is reduced in the portion buried in the ground, the lateral pressure in the ground is reduced and the traction force required for pulling can be reduced. The processing can be performed without forcing the driving device provided in the above.

Therefore, when the driving length of the buried pile is known in advance, the digging depth of the digging casing should be excavated as deep as possible in accordance with the driving depth (pile length). The pulling force at the time of pulling out the pile can be reduced. When excavating deeply, the intermediate casing 4
b and auger screw 5 are successively added,
It will be possible to excavate deep. In this case, the earth removal can be performed by the auger screw 5 as described above, so that the excavation by the excavation casing 4 does not interfere.

As described above, according to the present embodiment, even if the pile is deeply driven, the pre-treatment can be easily performed and the pull-out operation can be simplified, so that the pile as a whole can be used for redevelopment work or the like. The removal of the foundation pile can be performed efficiently, and as a result, the removal of the pile can be performed economically.

Further, as a drilling device for carrying out the method for pre-pulling a buried pile according to the present invention, if a conventional two-axis drive type driving device is employed in an earth auger machine, an auger screw is used for one of the shafts. By attaching the excavating casing to one of the shafts, the desired construction method can be performed without making a major change, and the apparatus can be simplified, so that there is an effect of being economical.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of an excavator used in a pre-pulling pre-pulling method for buried piles.

FIG. 2 is a diagram illustrating an excavation mode of a pile removal pretreatment.

FIG. 3 is a diagram showing a conventional pile removal pre-processing work mode.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 excavating device 2 drive device 3 two-axis power distribution device 4 excavating casing 4 d cutter attached to tip of excavating casing 5 auger screw 5 b screw cutter 6 a, 6 b joint 7 water supply pipe 8 steady rest mechanism 10 rotation mechanism 20 earth auger machine 21 Base machine 22 Leader 23 Wire rope 24 Hoist A Pile

Claims (3)

[Claims] 1. Using a two-axis driven earth auger machine, one of the shafts is provided with a drilling casing having a cutter at a tip capable of drilling around a target pile, and the other shaft is provided with an auger screw. Arranging, cutting the ground around the pile with the excavating casing and simultaneously excavating and discharging with an adjacent auger screw, excavating around the pile to a required depth, and facilitating pulling out of the pile. Pre-pulling method for buried piles. 2. The method according to claim 1, wherein the digging is advanced by digging with the auger screw when digging with the digging casing and the auger screw. 3. An earth auger machine has a biaxial drive device having a cutter provided at one end thereof with a cutter at its tip and capable of excavating around a pile, and an auger screw connected to the other shaft. The excavation casing and the auger screw are provided with a steady rest that can keep their axes parallel to each other in the vicinity of the extremity, and the auger screw has its extremity set to be longer than the excavation casing so that advanced excavation can be performed. An excavating device for pre-pulling underground piles.