JPH0676690B2 - Pile hole excavation method and equipment for removing existing piles and excavating pile holes for new piles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention removes an existing pile that is buried in the ground and is no longer needed, and excavates a pile hole of a new pile, and a method for excavating the pile hole. Regarding the device.

<Prior Art> As is well known, a large number of piles are formed in the ground for the purpose of constructing a foundation of a building or for ground improvement.

However, when dismantling an old building and constructing a new one in its place, or when newly improving the ground, it is often necessary to remove the old existing piles as an obstacle.

In general, new buildings are larger than old ones, and it is customary to make them taller.Therefore, old existing piles cannot support new buildings sufficiently, and even if old piles are used, Even if it is used as it is as a support pile for a new building, strength deterioration occurs due to the passage of concrete and reinforcing bars for a long time, and it has little utility value,
It is a danger.

<Problems to be Solved by the Invention> Conventionally, in the case of a relatively small-scale existing pile, the surroundings of the existing pile are excavated or extracted by an earthmoving machine to remove the pile, and a new pile hole is excavated. However, in reality, it cannot be removed by large-scale existing piles, or it is gradually removed using an extremely large-scale civil engineering machine over a long period of time.

If the old existing piles cannot be removed by any means, new pile holes will be drilled in places where these piles are avoided, and the design of the entire building will have to be changed, resulting in extremely economical loss. .

<Means for Solving the Problems> Therefore, the present invention is to apply the above-mentioned excavation by attaching a bucket having a chuck mechanism and excavation means to an upper portion of an existing pile that is embedded in the ground while rotating the bucket. By excavating the ground around the upper part of the existing pile by means of expanding the diameter, the existing pile is radially broken by the jet water jetted from the bucket,
The upper part of the broken existing pile is fixed above the broken part of the existing pile by the chuck mechanism to the bucket, the bucket is rotated, and the reaction force is received by the lower part of the existing pile to cut the upper part from the broken part. And a bucket hole excavation method characterized in that the existing pile is removed by removing the existing pile and a bucket with an open lower surface that is attached above the existing pile, and the bucket has a disk-shaped upper surface portion. And a peripheral wall portion that hangs from the upper surface portion. The upper surface portion is provided with a first jet water jetting mechanism that hangs down in a bucket and jets jet water in a downward direction and a lateral direction, and a lower edge of the peripheral wall portion. Is provided with a second jet water injection mechanism for injecting jet water at least in the lateral direction, an excavation means for excavating the periphery of the existing pile is provided, and a chuck mechanism is provided on the peripheral wall portion so that it can be attached to the existing pile. The first and second jet water injection mechanisms and the second jet water injection mechanism substantially break the existing pile in the radial direction, and the excavation means excavates the periphery of the existing pile to open a pile hole for a new pile. The present invention provides a pile hole excavating device characterized by:

<Examples> The present invention will be described in detail below with reference to the examples of the drawings.

The pile hole excavating device 1 according to the present invention has a bucket 2 having an open lower surface which is attached to an upper portion of an existing pile a and is rotatable, and the bucket 2 has a disk-shaped upper surface portion 3 and the upper surface portion. 3 and a peripheral wall portion 4 that hangs down. The upper surface portion 3 is provided with a first jet water jet mechanism 5 that hangs down in the bucket 2 and jets jet water downward and laterally, and jet water is jetted at least laterally at the lower edge of the peripheral wall portion 4. A second jet water jet mechanism 6 for jetting is provided. Further, a chuck mechanism 7 is provided on the peripheral wall portion 4 so that the chuck mechanism 7 can be fixed to the existing pile a, and at the lower edge of the peripheral wall portion 4, excavation means 8 for excavating the ground around the existing pile a is provided.

Explaining a more specific configuration of the excavation device 1 described above,
The upper surface portion 3 has a disk shape, and a cylindrical peripheral wall portion 4 hangs downward from the peripheral edge, and the lower surface is open.

The inner diameter of the peripheral wall portion 4 is substantially equal to the outer diameter d of the existing pile a, and the diameter of the upper surface portion 3 is substantially equal to the diameter D of the pile hole of the new pile.
However, when the casing 9 is used, the casing 9
The wall thickness of is reduced from the diameter of the pile hole.

The peripheral wall portion 4 is provided with a chuck mechanism 7 capable of fixedly fixing the existing pile a. According to the illustrated embodiment, the chuck mechanism 7 is arranged radially at intervals of 90 degrees, which is obtained by dividing the circumference into four parts.
The first pressing member 11 projects inside the bucket 2, and the first pressing member 11 presses the outer peripheral surface of the existing pile a to fix the existing pile a and the bucket 2 in a fixed manner. This first pressing member
The reference numeral 11 is stored in the peripheral wall portion 4 when the cylinder mechanism 10 is not operating.
Does not hinder the rotation of. Further, in the illustrated embodiment, the second pressing member 12 is projected to the outside of the peripheral wall portion 4, and the second pressing member 12 is pressed against the inner surface of the casing 9 inserted into the peripheral portion of the existing pile a so that the casing 9 is And the bucket 2 can be fixedly fixed. Incidentally, it is preferable to form fine unevenness for preventing slippage on the inner surface of each pressing member 11, 12.

Further, in the excavation device 1 described above, the swivel joint 13 is provided at the center of the upper surface portion 3 of the bucket 2, and the swivel joint 13 is provided with the first jet water injection mechanism 5 downward. The first jet water injection mechanism 5 is provided with a downward high-pressure water injection nozzle 15 and a horizontal high-pressure water injection nozzle 16 at the lower end of a high-pressure water pipe 14 which is vertically provided via a packer (not shown). It is a thing. In addition, a second jet having a high-pressure water passage 17 running in the longitudinal direction on the peripheral wall portion 4 of the bucket 2 and a downward high-pressure water jet nozzle 18 and an inward high-pressure water jet nozzle 19 at the lower end of the high-pressure water passage 17. Water injection mechanism 6
Is provided, the high-pressure water jetted from the inward high-pressure water jet nozzle 19 of the second jet water jet mechanism 6 is directed toward the center of the bucket 2, and the high-pressure water jet nozzle 16 of the first jet water jet mechanism 5 is provided. And the high-pressure water jet nozzle 19 of the second jet water jet mechanism 6 are positioned at the same height.

Further, the lower edge of the peripheral wall portion 4 is provided with excavating means 8 for expanding the diameter d of the pile hole of the existing pile a so as to correspond to the diameter D of the new pile. The excavating means 8 has a collar portion 20 extending from the lower edge of the peripheral wall portion 4 as shown in FIGS. 4 to 5, for example.
The through holes 21 are opened at appropriate angular intervals, and the swingable excavation member 22 is made to face the through holes 21 from the lower surface side of the collar portion 20.
That is, a through hole 21 is opened on the radiation of the collar portion 20, a support shaft 23 extending in the radial direction is provided below the through hole 21, and a drilling blade is provided at the tip.
A hook-shaped or mountain-shaped excavation member 22 having 24 is rotatably attached to the support shaft 23. Then, one side of the excavation member 22 is formed longer than the length between the inner edge portion 21 'of the through hole 21 and the support shaft 23, and one side 22a, 22b of the excavation member 22 is formed on the lower surface side of the inner edge portion 21'. It can be locked to. In the illustrated embodiment, the excavating member 22 has a short width, the through holes 21 are provided in parallel so as to correspond to the short excavating member 22, and a gap is provided between the excavating members 22.

On the other hand, when the casing 9 is inserted into the peripheral portion of the existing pile a to protect the wall surface of the pile hole, a high-pressure water channel (not shown) is also formed in the casing 9 and the high-pressure water channel of the high-pressure water channel is formed. It is also possible to provide a high-pressure water jet nozzle at the lower end and to provide a third jet water jet mechanism capable of jetting jet water downward from the high-pressure water jet nozzle.

One embodiment of the concrete configuration of the excavating device 1 according to the present invention is as described above, and the excavating device 1 is used to remove old unnecessary existing piles a buried in the ground and to provide new pile holes. Is established by the following method.

That is, first, the casing 9 is pushed into the peripheral portion of the existing pile a by the tubing device 25. The outline of the tubing device 25 is, as shown in FIGS. 6 to 7, a chuck portion 27 that can be reduced in diameter on a base 26, a jack portion 28 that supports the chuck portion 27 so as to be vertically movable, and a jack portion 28. And a rocking portion 29 for rocking. Chuck part 27 of this tubing device 25
The casing 9 is fastened to the peripheral portion of the existing pile a while the casing 9 is fixedly attached and the jack portion 28 and the swinging portion 29 are used to swing the casing 9. At this time, when the casing 9 provided with the third jet water injection mechanism is used, jet water can be jetted downward from the high-pressure water jet nozzle to excavate the ground of the peripheral wall portion 4.

Then, a pillar material 30 of a civil engineering machine such as a kelly bar of an earth drill machine or a drilling pipe of a reverse machine is connected to the center of the upper surface of the upper surface portion 3 of the bucket 2, and the bucket 2 is suspended by a crane by a wire. The swivel joint 13 is connected to the high-pressure water pipes 14 of the jet water injection mechanisms 5 and 6, and the high-pressure water hose (not shown) of the high-pressure water passage 17 individually, and each jet is provided at the rear end of the high-pressure water hose. An ultra-high pressure water jet device (not shown) capable of controlling jet water is connected to each of the high-pressure water jet nozzles 15, 16, 18, and 19 of the water jet mechanisms 5 and 6. Also, the cylinder mechanism of the chuck mechanism 7
A hydraulic hose extending from a hydraulic mechanism (not shown) is connected to 10.

The above-mentioned ultra-high pressure water jet device has a maximum of 3800
It has the capacity to discharge water at a maximum of 86 liters / minute at a pressure of Kg / cm ² , and it jets from each high-pressure water jet nozzle 15, 16, 18, 19 of each jet water jet mechanism 5, 6. Water becomes extremely high pressure, and concrete and rebar can be cut sufficiently.

Then, the casing 9 is pushed in to remove the earth and sand above the existing pile a, and the bucket 2 suspended in the air is lowered while being rotated in the forward and reverse directions, for example, every 180 degrees by the pillar member 30, and at the same time, the first jet water jet is performed. The high-pressure water jet nozzle 15 of the mechanism 5 jets high-pressure water containing fine granular abrasives downward.

When the high-pressure water is injected from the high-pressure water injection nozzle 15 while rotating the bucket 2 forward and backward and descending at a low speed, a vertical hole b is gradually formed at the center of the existing pile a by the pressure of the high-pressure water.

On the other hand, since the excavation means 8 is provided in the collar portion 20 at the lower edge of the bucket 2, when the bucket 2 rotates, the excavation means 8 excavates the ground around the existing pile a and expands the pile hole. In the excavation by the excavating means 8, when the bucket 2 rotates, the excavating blade 24a on the front side in the rotating direction is pressed by the earth and sand and rotates backward, and the upper surface of the excavating blade 24b on the rear side in the rotating direction passes through the hole. 2
The inner edge portion 21 'of 1 is contacted from below. When the bucket 2 is further rotated in this state, the excavation member 22 cannot rotate any more, and the excavation blade 24a on the front side cuts into the ground. When the excavating blade 24a bites, the earth and sand are pushed up along the upper surface of the excavating blade 24a and discharged through the front half of the through hole 21 to the upper surface of the bucket 2. At this time, since one side 22b of the rear excavating member closes the latter half of the through hole 21, the excavated earth and sand will not return to the pile hole again. Then, when the bucket 2 is reversed, the excavating blade 24b opposite to the above excavates the ground, and one side 22a of the other excavating member closes the latter half of the through hole 21 to hold the earth and sand.

When the above work is repeated, the bucket 2 is gradually attached to the upper side of the existing pile a, and once the packer is placed on the upper surface of the existing pile a, it cannot be further lowered and the collar portion 20
Sediment collects on top of the.

The earth and sand accumulated in the collar portion 20 are pumped upward between the casing 9 and the side wall portion 4, opened on the upper surface portion 3 and accumulated also above the bucket 2 from the discharge port 3 ′.

Therefore, the downward jet of high-pressure water from the high-pressure water jet nozzle 15 of the first jet water jet mechanism 5 is stopped and the first jet water is rotated while rotating the bucket 2 forward and backward every 90 degrees or 180 degrees. High-pressure water containing fine granular abrasives is jetted from the lateral high-pressure water jet nozzles 16 of the jetting mechanism 5 and the high-pressure water jet nozzles 19 of the second jet water jetting mechanism 6 facing the center (FIG. 2). ). The high-pressure water jetted from the high-pressure water jet nozzle 16 of the first jet water jetting mechanism 5 is the existing pile a.
Is horizontally broken from the center to the outer circumference, and the high-pressure water jetted from the high-pressure water jet nozzle 19 of the second jet water jet mechanism 6 horizontally breaks the existing pile a from the outer circumference to the center and the existing pile a. The rebar c near the outer periphery of is cut.

In this state, it may not be possible to sufficiently cut the existing pile a in the lateral direction, so the open upper end of the vertical hole b formed by the first jet water injection mechanism 5 at the center of the existing pile a should be tightly closed with a packer. By injecting high-pressure water from the high-pressure water injection nozzles 15 and 16 to increase the pressure in the cutting portion of the existing pile a with water, the unbroken concrete portion is cut. In this way, the high-pressure water jet nozzle of the first jet water jet mechanism 5
16 and the high-pressure water jet nozzle of the second jet water jet mechanism 6
When the existing pile a is sufficiently ruptured in the radial direction at 19 and the pressure inside the cutting portion is made high, the injection of high-pressure water from each nozzle 16, 19 is stopped, the cylinder mechanism 10 is operated, and the broken portion of the existing pile a is removed. While firmly fixing the outer peripheral surface with the first pressing member 11,
The bucket 2 is firmly fixed to the casing 9 by the second pressing member 12.

When the tubing device 25 is operated to swing the casing 9 in this state, the bucket 2 swings together with the casing 9, but the existing pile a does not swing. Therefore, the strain force generated by the swing of the casing 9 causes the existing pile to swing. By acting on the upper end portion of a, the broken portion is threaded and the upper end portion of the existing pile a is cut. In this case, in particular, the second jet water injection mechanism 6
Rebar c that could not be cut with the high-pressure water jet nozzle 19 of c
Is cut together with the thread cutting of the existing pile a.

Therefore, the concrete portion of the existing pile a and the reinforcing bar c are almost cut by the high-pressure water jet nozzles 16 and 19.
The concrete portion is destroyed by water pressure by making the inside of the cutting of the existing pile a high pressure with water, and the rebar c is also sufficiently cut by rotating the upper end portion of the existing pile a.

By the above-mentioned operation, the fractured part of the existing pile a is entirely cut in the radial direction, so the swing of the tubing device 25 is stopped,
By operating the cylinder mechanism 10 and retracting the second pressing member 12, the casing 6 is removed from the outer periphery of the bucket 2, and the upper portion of the existing pile a where the first pressing member 11 has been cut is fixedly attached to the bucket 4. By raising, the earth and sand accumulated on the upper surface of the bucket 2 can be removed to the ground, and the upper part of the broken portion of the existing pile a can be removed to the ground.

Then, after removing the upper part of the existing pile a, the casing 6 is lowered again by the tubing device 25, and the bucket 2 is lowered in the same manner as above to adhere the casing 2 to the upper portion of the existing pile a. A part of the upper part of the pile a can be cut and removed, and the ground around the existing pile a can be excavated to expand the diameter of the pile hole. By repeating this work in order, the entire length of the existing pile a can be increased from the ground. It is possible to remove and open a large pile hole for a new pile.

According to this embodiment, since the structure of the bucket 2 is simple and the casing 9 is used, the hole wall can be sufficiently protected.

8 to 11 show an embodiment of the excavating device 1 when the tubing device 25 is not used. The excavating device 1 in this embodiment is different from the above-described embodiment in that the bucket 2 rotates by itself. In that it has 31 means.

Explaining the specific configuration of the excavator 1, two hydraulic motors 32, 32 with reduction gears that constitute the rotation means 31 are installed on the upper surface of the upper surface 3 of the bucket 2 so as to face each other in the radial direction.
A downward rotation shaft 33 extending from each hydraulic motor 32 is passed through the upper surface portion 3 to be positioned inside the bucket 2, and a drive gear 35 meshing with an internal gear of the rocking gear 34 is provided at the tip of the rotation shaft 33. Set up. Then, a cylindrical rotating frame 36 provided above the inside of the bucket 2 and a first chuck mechanism 7a are provided inside the rotating frame 36 so as to be rotatable. The rotating frame 36 and the first chuck mechanism
7a is rotatably supported by a shelf plate member 37 installed in the middle of the inner surface of the peripheral wall portion 4, and is supported so that the rotating frame 36 and the first chuck mechanism 7a can freely rotate with respect to the peripheral wall portion 4. To do.

The first chuck mechanism 7a described above is configured so that the cylindrical material is vertically
It consists of divided semi-circular chuck frames 38, and the inner surface of each chuck frame 38 is formed with fine irregularities to prevent slipping
A plurality of vertical strips 39 are formed on the inner surface of 36, and a vertical groove 40 for fitting the vertical strip 39 is formed on the outer surface of each chuck frame 38 so as to correspond to the vertical strip 39, and the first chuck mechanism 7a is compressed. Rotating frame 36 by chuck frame 38 and vertical strip 39 in both diameter and diameter expansion states
At the same time, the first chuck mechanism 7a is configured to be rotatable.
Then, each chuck frame is provided on the upper edge of the first chuck mechanism 7a.
There is provided a first cylinder mechanism 10a for approaching 38 to reduce the diameter of the internal space or to increase the diameter by separating.

Also, the second chuck mechanism 7b described above has substantially the same configuration as the first chuck mechanism 7a described above, and the second chuck mechanism 7b shown in FIGS.
As shown in the figure, it consists of a semi-arcuate chuck frame 41 obtained by vertically dividing a cylindrical material into two parts, and each chuck frame 41 has minute irregularities for slip prevention formed on the inner surface thereof. The vertical groove 42 is formed on the outer surface of each chuck frame 41, and the vertical groove 43 is formed on the outer surface of each chuck frame 41 so as to fit the vertical groove 42. Even in this state, the chuck frame 41 and the vertical strip 42 allow the second chuck mechanism 7b to rotate together with the peripheral wall portion 4. Then, a second cylinder mechanism 10b is provided at the upper edge of the second chuck mechanism 7b to allow the chuck frames 41 to approach each other to reduce the diameter of the internal space or to increase the diameter by separating the inner space, and the second cylinder mechanism 10b is formed at the lower end of the peripheral wall portion 4. The annular receiving member 44 receives the lower edge of the second chuck mechanism 7b.

Further, a collar portion 20 is provided at the lower edge of the bucket 2, through holes 21 are radially formed in the collar portion 20, and each through hole 21 faces the rotatable excavating means 8.

Further, the first jet water jetting mechanism 5 is hung down at the center of the upper surface portion 3, and the first chuck mechanism 7a of the side wall portion 4 and the second
Horizontal high-pressure water jet nozzle 19 between chuck mechanism 7b
The downward high-pressure water jet nozzle 18 is provided at the lower end of the side wall portion 4.

The reference numerals not described in the embodiments of FIGS. 8 to 11 have the same configurations as those of the embodiments of FIGS. 1 to 5, and the description thereof will be omitted.

The following method is used to remove old unnecessary existing piles a buried in the ground by using the excavator 1 of this embodiment and to open a pile hole for a new pile on the spot.

That is, a pillar member 30 of a civil engineering machine such as a kerry bar of an earth drill machine or a trilling pipe of a reverse machine is connected to the center of the upper surface 3 of the bucket 2, and the bucket 2 is connected to a crane (not shown) by a wire 45. Hang on. Then, the high-pressure water pipes of the jet water injection mechanisms 5 and 6 and the high-pressure water hose for each high-pressure water flow path are individually connected to the swivel joint 13, and the jet water injection mechanisms 5 and 6 are provided at the rear end of the high-pressure water hose. An ultra-high pressure water jet device (not shown) capable of controlling the jet water is connected to each of the high pressure water jet nozzles 15, 16, 18, and 19. Also, both hydraulic motors 32, 32 and the first
A hydraulic hose 46 extending from a hydraulic mechanism (not shown) is connected to the cylinder mechanism 10a of the chuck mechanism 7a and the cylinder mechanism 10b of the second chuck mechanism 7b.

When the above-mentioned preparation work is completed, the bucket 2 suspended in the air is lowered by rotating the column member 30 in the forward and reverse directions, for example, every 180 degrees, and at the same time, the high-pressure water injection nozzle 15 of the first jet water injection mechanism 5 is moved. From which high-pressure water containing fine-grained abrasive is jetted. When high-pressure water is injected from the high-pressure water injection nozzle 15 while rotating the bucket 2 in the forward and reverse directions and descending at a low speed, a vertical hole b is gradually formed at the center of the existing pile a due to the pressure of the high-pressure water and the first hole is formed. Jet water injection mechanism 5
Is gradually inserted, and the excavation means 8 provided in the collar portion 20 excavates the ground at the peripheral portion of the existing pile a to expand the diameter of the pile hole, and the bucket 2 gradually sinks into the ground. The high-pressure water injection nozzle 18 provided at the lower end of the bucket 2 may be used to inject high-pressure water downward to excavate the ground on the outer periphery of the existing pile a together with the excavation means 8. And the bucket 2 is the existing pile a
When the packer 47 is placed on the upper surface of the existing pile a, it cannot be further lowered. Therefore, the injection of high-pressure water from the high-pressure water injection nozzle 15 and the high-pressure water injection nozzle 18 is stopped, and the bucket 2 is moved every 90 degrees or 18 degrees.
A fine granular abrasive is contained from each high-pressure water jet nozzle 16 of the first jet water jet mechanism 5 and each high-pressure water jet nozzle 19 of the second jet water jet mechanism 6 while rotating forward and backward at every 0 degrees. High-pressure water is sprayed. The high-pressure water jetted from each high-pressure water jet nozzle 16 is horizontally broken from the center of the existing pile a toward the outer circumference, and the high-pressure water jetted from each high-pressure water jet nozzle 19 is horizontal from the outer circumference of the existing pile a to the center. Along with the breakage, the reinforcing bar c near the outer circumference of the existing pile a is cut.

In this state, it may not be possible to sufficiently cut the existing pile a in the lateral direction, so the open upper end of the vertical hole b formed by the first jet water injection mechanism 5 at the center of the existing pile a is tightly closed by the packer 47. Then, high-pressure water is injected from the high-pressure water injection nozzle 16 to increase the pressure inside the cutting of the existing pile a with water, and the concrete portion which has not been broken is cut. In this way, when the existing pile a is sufficiently ruptured in the high-pressure water jet nozzle 16 and the high-pressure water jet nozzle 19 and the inside of the cutting is made to have a high pressure, the jetting of the high-pressure water from the nozzles 16 and 19 is stopped. Oil is sent under pressure to the cylinder mechanism 10a of the first chuck mechanism 7a and the cylinder mechanism 10b of the second chuck mechanism 7b to reduce the diameters of the first chuck mechanism 7a and the second chuck mechanism 7b, and to break the existing pile a. The outer peripheral surface above the first chuck mechanism
7a is firmly fixed, and the outer peripheral surface of the existing pile a below the broken portion is strongly fixed by the second chuck mechanism 7b.

When both hydraulic motors 32, 32 are driven in this state and the oscillating gear 34 is rotated by the drive gear 35, the oscillating gear 34 causes the rotary frame to rotate.
Since the first chuck mechanism 7a is rotated via 36 but the second chuck mechanism 7b is not rotated, the first chuck mechanism 7a is rotated.
The strain force generated by the rotation of (1) acts on the upper end portion of the existing pile a and is received by the second chuck mechanism 7b, and the broken portion is screwed to cut the upper end portion of the existing pile a. In this case, in particular, a part of the reinforcing bars c that could not be cut by the high-pressure water jet nozzle 19 of the second jet water jet mechanism 6 is cut together with the thread cutting of the existing pile a.

By the above-mentioned operation, the fractured part of the existing pile a is entirely cut in the radial direction, so that the rotation of the oscillating gear 34 is stopped and the oil is supplied to the second cylinder mechanism 10b to supply the second chuck mechanism 7b.
By expanding the diameter of b, it is removed from the outer circumference of the existing pile a, and the first chuck mechanism 7a is fixed to the outer circumference of the existing pile a while the diameter of the first chuck mechanism 7a is reduced.
While the excavated earth and sand are placed on 10 and the upper surface part 3, the upper part of the fractured part of the existing pile a rises together with the bucket 2 to discharge the earth and sand to the ground and remove the upper part of the existing pile a to the ground. it can.

Then, after removing the upper part of the existing pile a, the bucket 2 is lowered again to adhere to the upper part of the existing pile a, and the upper part of the existing pile a is cut and removed by the same operation as described above, and the pile hole The diameter can be increased, and by repeating this operation in order, the entire length of the existing pile a is removed from the ground, and
Expanded pile holes for new piles can be opened on the spot.

According to this embodiment, it is not necessary to insert the casing 9, so that the construction is simple. Further, since the conventional construction machine such as the kelly bar is used and the tubing device 25 is not used, the construction facility is simplified.

FIG. 12 shows still another embodiment of the present invention. In this embodiment, the excavation means 8 provided in the bucket 2 does not collect the earth and sand generated when excavating the ground on the upper surface portion 3, but immediately discharges it to the ground using a sand pump, an air lifter or the like (not shown). It was done like this. Therefore, in this embodiment, the upper surface portion 3 is formed to have the same diameter as the peripheral wall portion 4, and
The lift mud pipe 48 is exposed above the collar 20.

According to this embodiment, since the sand and sand are not accumulated on the bucket 2, quick construction can be performed and the construction period can be shortened. Further, the structure of the bucket 2 can be simplified.

This embodiment can be freely applied to the Benners method and the Benoto method using the casing 9 and the ground drill method and the reverse method not using the casing 9.

Although the structure and method of the device of the present invention have been described based on the embodiment of the drawings, the present invention is not limited to this embodiment and can be implemented in any manner unless the configuration described in the claims is changed. be able to.

<Effects of the Invention> In summary, according to the present invention, a rotatable bucket is attached to the peripheral edge of an existing pile buried in the ground, and the peripheral edge of the existing pile is excavated to expand the diameter of the pile hole. , The upper part of the existing pile is rotated and the existing pile is cut in the radial direction by the jet water so that the existing pile is cut. It can be removed, and at the same time the diameter of the pile hole can be expanded. Therefore, it is not necessary to newly drill a pile hole for a new pile, which simplifies the construction and shortens the construction period. Also,
Since the existing piles can be broken by jet water, there is no pollution due to noise or vibration, and even in residential areas and cities, it is possible to remove existing piles and open pile holes for new piles at the same time, effectively using the land, It is possible to construct a building as designed, which is of high practical value.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a vertical cross-sectional view showing a state at the beginning of excavation, FIG. 2 is a vertical cross-sectional view showing a state in which an existing pile is fractured in a radial direction, and FIG. Is III- in Figure 2
III line sectional view, FIG. 4 is a vertical sectional view of the excavating means, FIG. 5 is a bottom view of the same as above, FIG. 6 is a plan view of the tubing device, FIG. 7 is a front view of the same, and FIG. Longitudinal sectional view of the embodiment,
9 is a plan view of the same as above, FIG. 10 is a sectional view taken along line XX of FIG. 8, FIG. 11 is a sectional view taken along line XI-XI of FIG. 8, and FIG. 12 is a longitudinal sectional view showing still another embodiment. It is a figure. 1 ... excavator, 2 ... bucket, 3 ... top surface, 4 ...
... peripheral wall portion, 5 ... first jet water jetting mechanism, 6 ... second jet water jetting mechanism, 7 ... chuck mechanism, 8 ...
Excavation means.

Claims (2)

[Claims] 1. A bucket having a chuck mechanism and an excavating means is attached to the upper part of an existing pile that is buried in the ground while rotating, and the excavating means surrounds the upper part of the existing pile. The ground is excavated and the diameter is expanded, the existing pile is fractured in the radial direction by the jet water jetted from the bucket, and the upper part of the fractured part of the existing pile is fixed to the bucket by the chuck mechanism, and the bucket is rotated and the A pile hole excavation method, characterized in that the lower part of an existing pile receives the force to cut the upper part from the fractured part, and the upper part of the broken existing pile is lifted together with a bucket to remove the existing pile. 2. A bucket, which is attached to the upper side of an existing pile and has an open lower surface, has a disk-shaped upper surface portion and a peripheral wall portion hung from the upper surface portion, and the upper surface portion has a bucket inside. A first jet water jetting mechanism that hangs down and jets jet water downward and laterally is provided, and a second jet water jetting mechanism that jets jet water at least laterally is provided at the lower edge of the peripheral wall portion. At the same time, an excavating means for excavating the periphery of the existing pile is provided, and a chuck mechanism is provided on the peripheral wall portion so that it can be fixed to the existing pile, and the existing jet water jetting mechanism and the second jet water jetting mechanism are used to install the existing jet pile. A pile hole excavating device, characterized in that a pile is broken substantially in a radial direction, and the periphery of an existing pile is excavated by the excavating means to open a pile hole for a new pile.