JP2001288746A - Existing pile crushing and removing method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of conveniently and easily removing the existing pile at a reduced working space and its device in work for rebuilding such as building or the like by destroying a footing structure. SOLUTION: The head end section of the existing pile P is crowned with a casing 2 connected to a kelly bar 8 to dig the circumference of the existing pile P with an excavation edge 13 wile rotating the casing, at the same time, the existing pile P is crushed with a drill head 25, crushed pieces are pushed upward of the inside of the casing 2 with spiral blades 28, and when a portion aside for an required depth is dug, cutting edges 16 and 16 of cutters 15 and 15 are pushed against vertical reinforcement inside of the existing pile P to cut off while continuing the rotation of the casing 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for crushing and removing existing piles, and more particularly to a method for breaking and rebuilding an old building or other basic structure.
The present invention relates to a method and an apparatus for easily removing an existing pile with a small working space and easily.

[0002]

2. Description of the Related Art With the increasing number of works for destroying and rebuilding basic structures such as aging buildings, it has become necessary to remove existing piles and place new ones. ing. Existing piles are cast-in-place piles with reinforced cages or PC
It is a concrete pile and it is not easy to remove it because it is cast deep underground.

[0003] For example, in order to remove an existing pile, a tower that is longer than the existing pile is erected near the existing pile, a pulley is arranged at the top of the tower, and a wire rope is wrapped around the tower. Connected to the head of the pile, wound the other end of the wire rope around the drum of the hoist fixed to the ground,
It is rare that an existing pile is easily and easily pulled out of the ground by a removal device that drives a hoist to wind a wire rope around a drum.

[0004] Therefore, the excavator is driven to vibrate the existing pile while the exciter is attached to the head of the existing pile and the pulling force of the wire rope is applied. The need to minimize frictional resistance with
Various devices are required for implementation. Therefore, a large work space for installing these devices is required.

[0005]

However, the removal device using the above-mentioned tower is subject to various restrictions depending on the structure and condition of the existing pile, and its practicality is regarded as a problem.
In addition, there are various difficult problems such as the necessity of securing the safety of the drawing work such as a wire rope cutting accident, and the like, so that it is not practical. Furthermore, it is virtually impossible to remove existing piles in narrow places where large vehicles cannot pass or enter because there is no work space.

On the other hand, in the method of excavating and breaking an existing pile, a special device having a remarkable effect for excavating the soil around the existing pile has not been developed yet. In addition to this, the excavation and destruction and excavation removal steps are required, which increases the size and complexity of the work, requires a large work space, and is inefficient.

Accordingly, an object of the present invention is to provide an apparatus that can easily and quickly remove an existing pile.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention solves the above-mentioned problem by fitting a bottomed cylindrical body to the head end of an existing pile and rotating the existing pile around the bottom of the existing pile. While drilling down with the drilling blade provided at the lower end, the existing pile is crushed with the drill head with spiral blades provided at the shaft core of the bottomed cylindrical body, and the crushed pieces are crushed inside the bottomed cylindrical body with spiral blades When pushing up and digging down to the required depth, the cutting blade of the cutter provided inside the bottomed cylindrical body is pressed against the reinforcing bar in the existing pile to cut while continuing to rotate the bottomed cylindrical body. The present invention provides a method for crushing and removing existing piles.

According to this method, the existing pile is crushed sequentially from the head end portion into the bottomed cylindrical body, and even the reinforcing bars in the existing pile can be cut and removed as a series of steps. Moreover,
Since the bottomed cylindrical body can be made small and compact, the work vehicle needs to be a small heavy machine instead of a large heavy machine, and therefore a small work space is sufficient.

In addition, while the bottomed cylindrical body is fitted to the head end of the existing pile and rotated, the periphery of the existing pile is dug down by a cutting blade provided at the lower end of the bottomed cylindrical body. When the existing pile is crushed by a drill head with a spiral blade provided on the shaft core of the cylindrical body, the crushed pieces are pushed upward inside the bottomed cylindrical body by the spiral blade, and are dug down by a required depth, and While continuing to rotate the bottom cylindrical body, the cutting blade of the cutter provided inside the bottomed cylindrical body is pressed against the reinforced cage in the existing pile and cut, and the cut reinforced cage is placed in the casing with the cutting blade of the cutter. Provided is a method for crushing and removing an existing pile, characterized in that a casing is pulled up while being held and a cutting blade is retracted on the ground to discharge a reinforcing cage.

According to this method, the existing pile can be crushed sequentially from the head end in the cylindrical body having the bottom, and even the reinforcing bars in the existing pile can be cut and removed as a series of steps. Moreover,
Since the bottomed cylindrical body can be made small and compact, the work vehicle needs to be a small heavy machine instead of a large heavy machine, and therefore a small work space is sufficient. Furthermore, the steel cage in the existing pile can be discharged to the outside of the underground hole while being housed in the casing.

[0012] Then, a casing of a required depth to be fitted to the head end of the existing pile, a connecting portion of a rotary drive shaft connected to the upper bottom with the upper end of the casing closed, and a casing in the casing connected to the upper bottom. A housing extending in a predetermined length in the axial direction of the housing, a cutter disposed in the housing so as to be able to advance and retreat toward the inner peripheral surface of the casing, and a cutter connected to the lower end of the housing and extending in the axial direction at the axial center of the casing. There is provided an existing pile crushing and removing device comprising a drill shaft extending at a predetermined length and a drill head with a spiral blade detachably attached to a lower end portion of the drill shaft.

[0013] According to this device, the casing is fitted to the exposed head end of the existing pile and driven to rotate, whereby the head end can be crushed by the drill head with the spiral blades, and the existing pile can be crushed by the cutter. Rebar can be cut. In addition, the steel cage can be pulled up from the underground hole and discharged while being housed in the casing. In addition, since the casing can be made small and compact, it is sufficient for the work vehicle to be a small heavy machine instead of a large heavy machine, and therefore a small work space is sufficient.

Further, in the cutter, a pair of hydraulic cylinders are juxtaposed in a point symmetric arrangement on an inner bottom portion of a housing, and a cutting blade is detachably attached to a piston rod of each of the hydraulic cylinders. The present invention provides an existing pile crushing and removing apparatus characterized in that the piles are horizontally held in the diametric direction toward the inner peripheral surface of the casing. Therefore, since the reinforcing bar in the existing pile can be cut by the operation of the cutter under the hydraulic control, the crushing of the head end becomes easy.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 is a front view of the existing pile crushing and removing apparatus 1, FIG. 2 is a sectional view taken along line AA, FIG. 3 is a plan view, and FIG. 4 is a sectional view taken along line BB of FIG. In the figure, reference numeral 2 denotes a casing as a bottomed cylindrical body. The casing 2 is formed of a cylindrical body that fits into the head of the existing pile P. The upper part is open and has an annular flange portion 3 on the inner peripheral edge, and the lower part is open so that the existing pile P can be fitted. Engagement projections 4 are formed on the upper surface of the flange 3 at regular intervals in the circumferential direction. Casing 2
Is a suitable depth that is convenient for transporting even a small truck as a single unit. A through hole 10 is appropriately formed on the outer peripheral surface of the upper part of the casing 2 as a pit, and a window hole 11 is formed in a lower part thereof so as to face each other in the diameter direction.
The window hole 11 is formed in the lower part 2b formed by dividing the casing 2 into two parts and connected by an upper part 2a and a band 12. Also,
Excavating blades 13 are fixed to the lower end of the casing 2 at regular intervals in the circumferential direction. The excavating blade 13 is a well-known one that can excavate earth and sand and rocks.

An upper bottom 6 having engaging recesses 5 for engaging with the engaging convex portions 4 of the flange 3 formed on the peripheral portion at regular intervals is placed on the flange portion 3 and fastened and fixed with bolts 7. Upper bottom 6
A connecting portion 9 of a rotary drive shaft (Kelly bar) 8 is provided at the center of the upper surface of the. A housing 14 having an oval cross section is connected to the center of the lower surface of the upper bottom 6 and extends in a predetermined length in the axial direction. A pair of cutters 15 are fixed to the bottom 23 of the housing 14 in a point-symmetric arrangement. The cutting blades 16 and 16 are disposed so as to be able to move forward and backward toward the inner peripheral surface of the casing 2 diametrically opposite each other. Therefore, as shown in FIG. 5, openings 17, 17 facing the cutters 15, 15 are formed on the arc-shaped side wall of the housing 14.
Are opened opposite to each other in the diameter direction. Cutter 15
A partition wall 18 is disposed horizontally at the upper part of the partition wall, and a reinforcing part 14a connected to the connecting part 9 is formed in a cross-shaped cross section at the upper part of the partition wall 18, and the parts other than the openings 17, 17 are closed and partitioned. The upper part from the wall 18 is formed in a closed room space.

As shown in FIGS. 2 and 4, the cutters 15, 15 have hydraulic cylinders 19, 19 arranged in a point-symmetrical arrangement on a bottom 23 in the housing 14, and one end thereof is connected to the bottom 23 by a bracket 20. The cutting blade 16 is detachably attached to the free end of the piston rod 21 at the other end. Guides 22 and 22 for guiding the movement of the cutting blade 16 are fixed to the bottom 23 of the housing 14 so as to face each other. The cutting blade 16 has a wedge shape and its cutting edge is positioned horizontally. This cutting edge is the casing 2
The maximum stroke for moving back and forth toward the inner peripheral surface of the existing pile P is sufficient for the radius length up to the outer diameter of the existing pile P. If there is a difference in the diameter of the existing pile P, the maximum movement stroke of the cutting blade 16 must be changed.
6 so that the piston rod 21 can be replaced with a longer one.
It is removable.

At the lower end of the housing 14, a drill shaft 24 extends in the axial direction by a predetermined length, and a drill head 25 is detachably connected to the drill shaft 24 by a lock portion 26. The lock portion 26 is provided in the window 1 of the casing 2.
1 through which the drill head 25 can be detached from the window hole 11. The drill head 25 is provided with a drill 27 at the tip, and a shaft 29 in which two spiral blades 28, 28 are spirally wound on top of each other in a diametrically opposed manner. A plurality of digging blades 30 are attached to the lower end of the spiral blade 28.

A construction example of the existing pile crushing and removing apparatus 1 according to the above configuration will be described. As shown in FIG.
In the ground surface E, the underground hole Q is excavated to a predetermined depth with a backhoe or an excavation bucket so that at least the head end of the existing pile P is exposed, and the earth retaining hole is retained in the underground hole Q. Of the earth retaining casing 31 is inserted.

Next, the existing pile crushing and removing apparatus 1 is lowered and inserted into the earth retaining casing 31. The casing 2 is connected via a connecting portion 9 to a lower end of a rotary drive shaft 8 such as a kelly bar which engages with a rotary drive 34 suspended from a crane 33 of the working vehicle 32. The work vehicle 32 has the advantage of requiring only a small heavy machine, and therefore does not require much work space.

As shown in FIG. 6 (B), when the casing 2 is fitted to the head end of the existing pile P with its axis aligned and the rotary drive shaft 8 is driven to rotate by the rotary drive 34, the casing 2 is rotated. Rotate. The excavating blade 13 attached to the lower end of the casing 2 excavates earth and sand around the outer periphery of the existing pile P, and
Digging in the longitudinal direction of the above to separate the existing pile P from the surrounding earth and sand. Further, the drill 27 of the drill head 25 crushes the head end to disassemble, and the crushed pieces are pushed up inside the casing 2 by the spiral blades 28, 28. Since the housing 14 has an oval cross section, the crushed pieces pushed up are accommodated in a space having a predetermined volume formed between the flat side surface and the casing 2. In addition, the excavating blade 30 and the spiral blade 2
Reinforced basket 50 in a range not exceeding 8, 28 (FIGS. 2, 4)
And concrete adhering to the casing 2
Is housed in a space between the inner peripheral surface of the housing and the housing.

After the required length of the head end is crushed by the drill head 25, as shown in FIG.
The zero vertical streak 51 reaches the flange 3 of the casing 2 and the casing 2 does not advance. Therefore, the hydraulic cylinder 1
When the piston rods 21, 21 are pushed out by driving the cutting blades 5, 15, the cutting blades 16, 16 are guided by the guides 22, 22 and protrude from the openings 17, 17 toward the inner peripheral surface of the casing 2. 4 and the casing 2 is rotating, so that the cutting edge of the cutting blade 16 cuts the longitudinal streak 51 assembled in the longitudinal direction of the rebar cage 50 as shown in FIG. The vertical streaks 51 move so as to be pressed against the inner peripheral surface of the casing 2 by the cutting edge of the cutting blade 16, but the inner peripheral surface of the casing 2 prevents the vertical streaks, thereby enabling effective cutting.

After the cutters 15 rotate to cut all the vertical stripes 51, the cutting blades 16
When the rotation of the rotary drive shaft 8 is stopped and pulled upward, and the existing pile crushing and removing device 1 is pulled up from the underground hole Q in a state where it is extended to the inner peripheral surface near the maximum stroke, the rebar cage 5
The horizontal streak 52 of 0 (see FIG. 4, but omitted in FIG. 2) is pulled up while being held in the casing 2 by being caught by the cutting blades 16, 16. Therefore, when the cutters 15, 15 are operated on the ground E to retract the cutting blades 16, 16 into the openings 17, 17, the reinforcing bar 50 in the casing 2 loses support and falls to the ground. In addition, underground hole Q
The crushed pieces in the inside are carried out to the ground E by a well-known excavation bucket or the like.

Next, as shown in FIG. 6 (C), the existing pile crushing and removing device 1 is inserted into the underground hole Q again, and the bentonite solution 40 is injected into the underground hole Q, and the same as above. The existing pile P is completely crushed and removed while repeating the above operation. The bentonite solution 40 is pumped from a water tank provided on the ground (not shown). Thus, the complete removal of the existing pile P is completed. However, there is a case where the diameter of the existing pile P has a large or small difference. In such a case, the same operation as described above is performed by replacing the casing with another casing having a different diameter.

The casing 2 is replaced by placing an upper bottom 6 on which the engaging concave portion 5 engages with the engaging convex portion 4 of the flange portion 3 of the casing 2 on the flange portion 3 and fastening and fixing the upper bottom 6 with bolts 7. Therefore, only the casing 2 is changed by attaching and detaching the bolt 7. The casing 2 is large and small in advance, and the flanges are formed with engaging projections 4 with which the engaging recesses 5 are to be engaged. Also, if the diameter of the casing 2 is large, the moving stroke of the cutting blade 16 of the cutter 15 may not reach the vertical streaks 51 of the rebar cage 50.
Replace 5 and 15 with the prepared long ones.

The underground hole Q after completion of the crushing and removing work of the existing pile P is provided with a hook 42 at the lower end of the rotary drive shaft 8 with a hook 42 as shown in FIGS. 4
1 and inserted into the underground hole Q to collect the bentonite solution 40 in the water tank,
Inject 3. Finally, as shown in FIG. 7 (C), the backfill work is completed by pulling out the earth retaining casing 31.

[0027]

According to the present invention described above, the entire pile can be removed while crushing the existing pile sequentially from its head end, so that all the mechanical work is safe, convenient, easy and quick. Piles can be removed. In addition, the casing has a diameter that is almost the same as the diameter of the existing pile,
Since it is sufficient to have the required depth, the entire device is extremely small and compact, so the work equipment is small and heavy.Therefore, there is no need for a large work space. Can be crushed and removed.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a side view of a main part of a housing in a casing.

6 (A) to 6 (C) are explanatory diagrams of an example of an existing pile crushing and removing construction. FIG.

FIGS. 7A to 7C are explanatory diagrams of a backfilling operation after the existing pile crushing and removing work.

[Explanation of symbols]

 P: Existing pile Q: Underground hole 1 ... Existing pile crushing and removing device 2 ... Casing 3 ... Flange part 4 ... Engagement convex part 5 ... Engagement concave part 6 ... Upper bottom 7 ... Bolt 8 ... Rotary drive shaft (Kelly bar) 9 ... Connecting part 10 ... Through hole 11 ... Window hole 12 ... Band 13 ... Drilling blade 14 ... Housing 15 ... Cutter 16 ... Cutting blade 17 ... Opening 18 ... Partition wall 19 ... Hydraulic cylinder 20 ... Bracket 21 ... Piston rod 22 ... Guide 23 ... Bottom part 24 ... Drill shaft 25 ... Drill head 26 ... Lock part 27 ... Drill 28 ... Spiral blade 29 ... Shaft 30 ... Drilling blade 31 ... Soil retaining casing 50 ... Reinforcing cage 51 ... Vertical streak 52 ... Transverse streak

Claims (4)

[Claims] 1. A bottomed cylindrical body is fitted to the head end of an existing pile and rotated down while excavating the periphery of the existing pile with a cutting blade provided at the lower end of the bottomed cylindrical body. When the existing pile is crushed by a drill head with a spiral blade provided on the shaft core of the cylindrical body, the crushed pieces are pushed upward inside the bottomed cylindrical body by the spiral blade, and are dug down by a required depth, and A method for crushing and removing an existing pile, characterized in that a cutting blade of a cutter provided inside the bottomed cylindrical body is pressed against a reinforcing bar in an existing pile to cut the pile while continuing to rotate the bottom cylindrical body. 2. A bottomed cylindrical body is fitted to the head end of an existing pile and rotated down while excavating the periphery of the existing pile with a cutting blade provided at the lower end of the bottomed cylindrical body. When the existing pile is crushed by a drill head with a spiral blade provided on the shaft core of the cylindrical body, the crushed pieces are pushed upward inside the bottomed cylindrical body by the spiral blade, and are dug down by a required depth, and While continuing to rotate the bottom cylindrical body, the cutting blade of the cutter provided inside the bottomed cylindrical body is pressed against the reinforced cage in the existing pile and cut, and the cut reinforced cage is placed in the casing with the cutting blade of the cutter. A method for crushing and removing existing piles, wherein the casing is lifted while being held, and the rebar cage is discharged by retracting the cutting blade on the ground. 3. A casing having a required depth to be fitted to a head end of an existing pile, a connecting portion of a rotary drive shaft connected to an upper bottom having a closed upper end of the casing, and a casing connected to the upper bottom. A housing extending in a predetermined length in the axial direction of the housing, a cutter disposed in the housing so as to be able to advance and retreat toward the inner peripheral surface of the casing, and a cutter connected to the lower end of the housing and extending in the axial direction at the axial center of the casing. An existing pile crushing and removing device comprising a drill shaft extending at a predetermined length and a drill head with a spiral blade detachably attached to a lower end portion of the drill shaft. 4. A cutter has a pair of hydraulic cylinders arranged side by side in a point-symmetric arrangement on an inner bottom portion of a housing, and a cutting blade is detachably attached to a piston rod of each of the hydraulic cylinders. The existing pile crushing and removing apparatus according to claim 3, wherein the piles are held horizontally in a diametric direction toward the inner peripheral surface of the casing.