JP4523851B2 - Drilling equipment for pile removal - Google Patents

Description

  Many piles are buried in the ground for building foundations or ground improvement. However, when rebuilding a building or renovating the ground, Often it is necessary to remove the existing piles) from the ground. The present invention relates to a drilling device used for drilling a ground around an existing pile when removing an existing pile buried in the ground, particularly in the case of a cast-in-place pile (also called a cast-in-place pile). It is powerful.

  Patent Document 1 and Patent Document 2 describe a technique for pulling out an existing pile buried in the ground. In order to drill holes around existing piles in these, an auger machine 102 attached to the leader 101 as shown in FIG. 13 is provided with a spiral blade 104 on the outer peripheral surface and a drilling blade 105 at the lower end. An excavation apparatus 100 configured by connecting cylindrical casings 103 so as to be rotationally driven is used.

  As shown in FIG. 14, the auger machine 102 is driven to lower the casing 103 while rotating, and the ground S around the existing pile P buried in the ground is drilled by the excavation blade 105 at the lower end. To do. Due to the function of the spiral blade 104, the casing 103 sinks below the ground S. At the same time, the soil around the existing pile P scraped by the excavating blade 105 is sequentially conveyed upward by the spiral blade 104 and discharged.

As shown in FIG. 15, when the lower end of the casing 103 reaches the lower end of the existing pile P and the existing pile P becomes separable from the ground S, the wire is hooked on the head of the existing pile P, Pull up with a winch or the like (Patent Document 1), or hold the existing pile P with a plurality of locking claws provided at the lower part of the casing 103 and lift the auger machine 102 to pull it up together with the casing 103 (Patent Document 2) ).
Japanese Patent Publication No. 5-63576 JP 2001-3362 A

  In the case where the existing pile P is a cast-in-place pile (a cast-in-place pile), the outer diameter of the existing pile P may not always be constant depending on the state of the ground S or the like. That is, if there is a locally soft part in the ground S, the part is expanded by the pressure of the poured concrete, and a pile P having a partially expanded bump Q as illustrated in FIG. 16 is formed. . When the periphery of the existing pile P having the bump Q is drilled by the conventional excavator 100 described above, the excavation operation is performed while cutting and crushing the bump Q with the excavation blade 105 at the lower end of the casing 103. However, at that time, a reaction force in a direction indicated by an arrow R in FIG. By the way, the inside of the casing 103 is formed hollow to allow the existing pile P to be inserted, and the inner diameter thereof is set slightly larger than the nominal outer diameter of the existing pile P. Therefore, the ground drilling work around the existing pile P is performed with a slight gap between the outer peripheral surface of the existing pile P and the inner peripheral surface of the casing 103. For this reason, when excavating the bump Q portion of the existing pile P, the posture of the casing 103 is inclined by the reaction force R. When drilling is carried out in a state where the casing 103 is inclined with respect to the axis of the existing pile P, not only the work efficiency is lowered, but the inner peripheral surface of the casing 103 is in contact with the outer surface of the existing pile P, and as a result, the casing There is a problem that 103 is worn and damaged, and the life is remarkably shortened.

  Therefore, it is conceivable that the entire casing 103 is made of a hard material that is not easily worn or damaged even if it contacts the existing pile P made of concrete. The disadvantage is that the cost is very high.

In order to solve the above-mentioned conventional problems, the means adopted by the present invention according to claim 1 is rotated so as to drill around the existing pile piled by a drilling blade provided at the lower end of the cylindrical casing. a drilling device capable of lowering while, above the digging edge of the inner peripheral surface of the device is provided with a drilling direction guide means which surrounds the side peripheral surface of the existing pile, the direction of drilling guide means, the upper and lower casing The rotation axis is set so that it is substantially parallel to the direction axis, and it consists of a plurality of rollers that can rotate freely. The diameter of the virtual inscribed circle that these rollers contact is set larger than the nominal outer diameter of the existing pile. It is the excavation apparatus for pile removal characterized by being made.

In order to solve the above-mentioned conventional problem, the means adopted by the present invention according to claim 2 is rotated so as to drill around the existing pile piled by a drilling blade provided at the lower end portion of the cylindrical casing. The excavation apparatus can be lowered while being provided above the excavation blade on the inner peripheral surface of the apparatus, and excavation direction guide means surrounding the side peripheral surface of the existing pile is provided. Excavation device for pile removal characterized in that it consists of a flange structure extending in the circumferential direction on the inner peripheral surface, and the inner diameter or inscribed circle diameter is set larger than the nominal outer diameter of the existing pile It is.

According to a third aspect of the present invention, the excavation direction guide means may be arranged in two or more rows at intervals in the vertical direction along the axial direction of the casing.

  In the excavating apparatus according to the present invention, since the excavation direction guide means surrounding the side peripheral surface of the existing pile is arranged above the inner peripheral surface, the existing pile has a bump, and when cutting this bump with a drilling blade, Even if an outward force is applied to the lower end, the excavation direction guiding means abuts against the surface of the existing pile, so that the attitude of the excavator can be prevented from tilting. Accordingly, during excavation work, the orientation of the casing is always maintained substantially parallel to the axis of the existing pile to prevent contact between the casing and the existing pile, so that the ground drilling around the existing pile is smoothly advanced. Moreover, since there is no possibility that the casing will be damaged by contact with the existing pile, the life of the casing can be extended. The inner diameter of the excavation direction guide means or the diameter of the inscribed circle is set to be larger than the nominal outer diameter of the existing pile. There is no fear.

  When the excavation direction guide means is composed of a plurality of rollers that are rotatably provided, it hardly interferes with the rotation of the casing when it comes into contact with the existing pile. On the other hand, in the case of a flange structure extending in the circumferential direction on the inner peripheral surface of the casing, the excavation direction guide means can be manufactured at a relatively low cost.

  When the excavation direction guide means is arranged in two or more rows at intervals in the vertical direction along the axial direction of the casing, the excavation direction guide means is placed on the surface of the existing pile when the attitude of the casing is about to be inclined. Since the contact is made at two or more places, the inclination of the casing can be prevented more reliably.

[First Embodiment]
In FIG. 1, the principal part of the excavation apparatus which concerns on this invention is shown. As shown in the figure, the present example is characterized in that the excavation direction guide means 20 is provided on the inner peripheral surface of the excavation head 10 detachably attached to the lower end portion of the cylindrical casing 103. The cylindrical casing 103 has a spiral blade 104 on the outer peripheral surface, and is connected to an auger machine (see FIG. 13) attached to a reader so as to be able to move up and down. .

  The excavation head 10 includes a cylindrical housing 11 attached to the casing 103, an excavation blade 12 attached to the lower end of the housing 11, and excavation direction guide means 20 disposed on the inner peripheral surface of the housing 11. Consists of The housing 11 is formed substantially the same diameter as the casing 103 or slightly larger as shown in the figure, and has an inner diameter that allows at least the existing pile P to be inserted therein. About the excavation blade 12 provided in the lower end of the housing 11, the thing common to the past can be used.

The excavation direction guide means 20 of this example is composed of a plurality of rollers 21 that are rotatably held by a bracket 22 fixed to the inner peripheral surface of the housing 11. The rollers 21 are arranged at regular intervals along the inner peripheral surface of the housing 11, and the respective rotation axes are set so as to be substantially parallel to the axes of the housing 11 and the casing 103. Therefore, these rollers 21 can rotate in accordance with the rotation of the casing 103 when abutting against the existing pile P. In addition, the diameter of the virtual inscribed circle X with which each roller 21 is in contact is the nominal outer diameter of the existing pile P so that the existing pile P inserted inside during the drilling operation and the roller 21 do not normally contact each other. It is set to be slightly larger. When a concrete numerical value is illustrated, when the nominal outer diameter of the existing pile P is about 1000 mm, the diameter of the virtual inscribed circle X may be set to about 1050 to 1100 mm.

  In the present example, the rollers 21 are arranged in two rows at two positions, a position near the excavation blade 12 at the lower end on the inner peripheral surface of the housing 11 and a position slightly apart upward. With this configuration, when an external force is applied to the casing 103 and tries to tilt, the roller 21 comes into contact with the outer peripheral surface of the existing pile P. 103 is excellent in posture stability.

  Since the roller 21 constituting the excavation direction guide means 20 rotates in contact with the existing concrete pile P, it is desirable to use a material excellent in wear resistance (for example, a carbon steel for machine structure S45C). Such a material is more expensive than a material constituting the casing 103 (for example, a general structural rolled steel SS41), but is used not for the entire casing 103 but for only a part of the excavation head 10. Therefore, an increase in manufacturing cost can be suppressed. Further, when the roller 21 is worn out, it can be easily replaced, and only the roller 21 that has been worn out can be replaced, so that the maintenance cost can be kept low.

  In addition, about the material of the housing 11 and the bracket 22 which do not contact the existing pile P, the material equivalent to the casing 103 may be sufficient, but it is also possible to make it the hard material equivalent to the roller 21 or the excavation blade 12 if desired. I do not disturb.

  Next, a procedure for pulling out an existing pile using the excavator constructed as described above will be briefly described. As in the prior art, the excavator 1 according to the present invention is connected to an auger machine 102 that can be moved up and down along a leader 101, as shown in FIG. In addition to the excavator 1, the reader 101 and the auger machine 102 are mounted on, for example, a crawler crane and are movable.

  To pull out the existing pile P, first excavate the ground S using a hydraulic excavator, etc., expose the pile head of the existing pile P buried in the ground, and then place an iron frame around the pile head Reserve space. When the reinforcing bar protrudes from the pile head of the existing pile P, this is cut off with a gas burner or the like. Thereafter, if necessary, an iron plate for preventing the fall is laid at a position where the crawler crane or the like on which the excavator 1 is mounted is stopped. Subsequently, the crawler crane is operated and moved onto the iron plate, and after the excavator 1 is positioned above the existing pile P as shown in FIG. 2, the excavator 1 is lowered together with the auger machine 102, as shown in FIG. Thus, the excavator 1 is put on the pile head of the existing pile P. That is, a part of the existing pile P is inserted into the excavation head 10 of the excavator 1.

  Subsequently, the auger machine 102 is driven to lower the excavator 1 while rotating, and the drilling of the ground S around the existing pile P is started. At this time, it is desirable to reduce the excavation resistance by injecting water or bentonite around the existing pile P according to the property of the ground S. As the excavator 1 rotates, the casing 103 sinks into the ground S by the function of the spiral blades 104 provided on the outer peripheral surface while the ground S is scraped off by the lower excavation blade 12. At the same time, the soil around the existing pile P is sequentially sent upward by the spiral blade 104. When the length of the existing pile P is sufficiently long and the first casing 103 alone does not reach the lower end of the existing pile P, the casing 103 is added and the drilling of the ground S is continued.

  Thus, as shown in FIG. 4, when the excavator 1 reaches the lower end position of the existing pile P and the existing pile P becomes separable from the ground S, the existing pile P is lifted to the ground. This includes means for tying a wire to the head of the existing pile P and pulling it up with a winch, means for holding the existing pile P with a locking claw provided in the casing 103 and lifting the auger machine 102 together with the casing 103, hydraulic chuck The means etc. which hold | grip the side peripheral surface of the existing pile P and push up sequentially are used. Moreover, the construction method which repeats the operation | work which cuts and falls a pile when the length exposed on the ground reaches appropriate length instead of pulling up the whole existing pile P at once is also employable.

  By the way, when the existing pile P is a site-made pile, depending on the situation of the ground S, it may have a bump Q protruding from the side peripheral surface as shown in FIG. When a hole is drilled around the existing pile P, the force in the direction indicated by the arrow R acts on the excavating blade 12 in an attempt to escape to the outside when the excavating blade 12 at the lower end collides with the bump Q. As described above, the casing 103 tends to incline with respect to the axis of the existing pile P. However, in the present invention, the excavation direction guide means 20 composed of a plurality of rollers 21 arranged in two upper and lower rows at appropriate intervals on the inner peripheral surface of the excavation head 10 abuts on the side peripheral surface of the existing pile P (arrow T To prevent the excavation head 10 and the casing 103 from tilting. That is, since the attitude of the excavation head 10 and the casing 103 can always be kept parallel to the existing pile P, there is no possibility that the casing 103 contacts the existing pile P and is damaged. Further, since the attitude of the excavator 1 is stabilized, the work efficiency is good.

  The bump Q of the existing pile P is cut and pulverized by the rotating cutting blade 12. At this time, it is the rotatable roller 21 portion in the excavation direction guide means 20 that contacts the side peripheral surface of the existing pile P. . That is, the excavation direction guide means 20 does not hinder the excavation head 10 and the casing 103 from rotating around the existing pile P.

  Of the excavator 1 according to the present invention, it is usually only the roller 21 that needs to be replaced. However, the excavator 1 is made of a sufficiently hard material that is not easily worn, thereby reducing the number of replacements and maintenance. Can do. On the other hand, the portion other than the roller 21 of the excavation direction guide means 20, the housing 11 of the excavation head 10, the casing 103, and the like do not have a possibility of coming into contact with the existing pile P, and therefore have a low hardness and are relatively inexpensive. It can be made of a material and there is very little need for replacement. Therefore, the present invention has an effect that the cost of parts replacement and maintenance can be remarkably suppressed.

[Second Embodiment]
When the excavation direction guide means 20 according to the present invention is constituted by the rollers 21, it is also conceivable to adopt a structure as shown in FIGS. In this example, a plurality of rollers 21 are rotatably supported by upper and lower brackets 23, 23 and integrated to form a roller unit U (see FIG. 7). On the other hand, the flanges 24 and 24 are fixed to the inner peripheral surface of the housing 11 of the excavation head 10 at an appropriate interval to form a mounting portion for the roller unit U. A protective member 25 is disposed between the flanges 24 and 24 along the inner peripheral surface of the housing 11 as necessary. Furthermore, it is desirable that the protective member 25 be replaceable.

  As shown in FIG. 6 (B), one roller unit U is formed by integrating a number of rollers 21 of about one-third to one-fourth of the entire rollers 21 constituting the excavation direction guide means 20. The bracket 23 that rotatably supports the roller 21 has an arc shape of about a third to a quarter of a circle in a plan view. This is because the roller unit U can be attached to and detached from the mounting portion between the flanges 24 and 24 fixed to the inner peripheral surface of the housing 11. The width dimension of the bracket 23 in a plan view is set smaller than the diameter of the roller 21. That is, when the roller unit U is mounted between the flanges 24, 24, as shown in FIG. 6B, only the roller 21 is the protective member 25 (or the inner peripheral surface of the housing 11) and the side peripheral surface of the existing pile P. The bracket 23 is set so as not to contact these.

  After the roller unit U is disposed between the flanges 24, 24, it is desirable that the roller units U be connected to each other and integrated over the entire circumference. For example, as shown in FIG. 8 (particularly, (B) and (C)), a joining portion 23a is provided at the end edge of the bracket 23 in each roller unit U, and the adjacent brackets 23, 23 are connected to each other by this joining portion 23a. A structure in which the bolts 26, nuts 27, etc. are joined and connected can be considered. By connecting the plurality of arc-shaped roller units U integrally, the roller unit U is not detached from between the flanges 24 and 24.

  In this example, since a plurality of arc-shaped roller units U are arranged between the flanges 24 and 24 and then all are connected and integrated, the flanges 24 and 24 are fixed to the housing 11 in advance. The roller 21 can be mounted. Further, when the roller 21 is worn or damaged, the roller unit U can be easily replaced or repaired by releasing the fastening between the roller units U. Furthermore, since the roller 21 is not fixed to the housing 11, the excavation head 10 can be easily manufactured.

  Consider a case where the ground around the existing pile P having the bump Q (see FIG. 5) is drilled in the excavation apparatus including the excavation direction guide means 20 configured as described above. When the excavating blade 12 collides with the bump of the existing pile P, an external force is applied to the excavating device, but the roller 21 of the excavating direction guide means 20 comes into contact with the side peripheral surface of the existing pile P, and the excavating head 10 and the inclination of the casing 103 are prevented and the posture is properly maintained. At this time, although the excavation head 10 is rotationally driven, the roller 21 in contact with the protective member 25 housed in the housing 11 moves on the side peripheral surface of the existing pile P while rotating. Therefore, even if the roller 21 comes into contact with the existing pile P, there is no possibility of hindering the rotational drive of the excavation head 10 and the casing 103. At this time, the bracket 23 that supports the roller 21 rotates around the existing pile P in the same direction as the excavation head 10 as the roller 21 rotates. That is, the integrated roller unit U rotates in the same direction as the excavation head 10. However, the rotation speed is reduced according to the diameter of the roller 21.

  In the excavation direction guide means 20, it is desirable that the roller 21 in contact with the existing pile P is made of a material having a relatively high hardness (for example, a carbon steel material for machine structure such as S45C). In this example, the roller 21 The protective member 25 is disposed along the inner peripheral surface of the housing 11 in order to prevent the housing 11 from contacting and damaging the housing 11. Further, since the protective member 25 is in contact with the inner peripheral surface of the housing 11, the protective member 25 is made of a material equivalent to or softer than the housing 11 so that the housing 11 is not damaged by the protective member 25. It is desirable. Therefore, the protection member 25 is easily damaged by contact with the hard roller 21, but can be replaced. Therefore, the contact surface with the roller 21 is maintained in an appropriate state by replacing it as necessary. Easy to do.

[Third Embodiment]
The mode of disposing the rollers 21 as the excavation direction guide means 20 in the excavation head 10 is 3 to 4 rows or more with an appropriate interval on the inner peripheral surface of the housing 11 as illustrated in FIG. Is also possible. According to such a configuration, the posture stability of the excavation head 10 and the casing 103 is further improved.

[Fourth Embodiment]
As shown in FIG. 10, the rollers 21 constituting the excavation direction guide means 20 may be arranged on the inner peripheral surface of the housing 11 so as to have a relatively large interval in the circumferential direction and not adjacent in the axial direction. Conceivable. Such a roller arrangement mode is advantageous in that the manufacturing cost can be reduced by reducing the number of rollers 21 used without impairing the posture stability of the excavation head 10 and the casing 103.

[Fifth Embodiment]
As shown in FIG. 11, the excavation direction guide means 20 can be configured by a flange 30 formed on the inner peripheral surface of the housing 11. Since the configuration is simpler than the structure using the roller 21, it can be manufactured at a very low cost. The flange 30 may be divided into a plurality of parts as shown in FIG. Further, as shown in FIG. 12, a configuration in which a plurality of arc-shaped flanges 31 are arranged on the inner peripheral surface of the housing 11 in the circumferential direction is also conceivable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a first embodiment of an excavation apparatus according to the present invention, in which FIG. (A) is a front view of a partial section of the excavation head, and FIG. (B) is a plan sectional view of the excavation head. It is the front view which carried out the partial cross section which shows the excavation apparatus which concerns on this invention attached to the auger machine, and the pile head part of the existing pile currently embed | buried in the ground. It is the front view which carried out the partial cross section which shows the state which covered the excavation apparatus which concerns on this invention attached to the auger machine on the pile head part of the existing pile currently embed | buried in the ground. It is the front view which carried out the partial cross section which shows the condition which drilled to the lower end part of the existing pile currently embed | buried in the ground with the excavation apparatus which concerns on this invention attached to the auger machine. It is the front view which carried out the partial cross section which shows the condition which is cutting the lump of the existing pile currently embed | buried under the ground with the excavation apparatus which concerns on this invention. FIG. 2 shows a second embodiment of the excavating apparatus according to the present invention, in which FIG. (A) is a front view showing a partial section of the excavating head, and FIG. (B) is a plan sectional view of the excavating head (for the flange 24). Half-section). FIG. 6 is a perspective view of a partially sectioned view showing an excavation head housing and a roller unit in an exploded manner, relating to a second embodiment of the excavation apparatus according to the present invention. FIG. 1A is a front cross-sectional view showing a main part of a housing and a roller unit of an excavation head, and FIG. 2B is a main part of the housing and the roller unit. FIG. 4C is a front cross-sectional view showing a joining portion between roller units. It is the front view which carried out the partial cross section of the excavation head which shows 3rd Embodiment of the excavation apparatus which concerns on this invention. It is the front view which carried out the partial cross section of the excavation head which shows 4th Embodiment of the excavation apparatus which concerns on this invention. 5 shows a fifth embodiment of the excavation apparatus according to the present invention, in which FIG. (A) is a front view of a partial section of the excavation head, and FIG. (B) is a plan sectional view of the excavation head. It is a plane sectional view of an excavation head showing a different mode of a 5th embodiment of an excavation device concerning the present invention. It is the front view which carried out the partial cross section which shows the conventional excavation apparatus attached to the auger machine, and the pile head part of the existing pile currently embed | buried under the ground. It is the front view which carried out the partial cross section which shows the state which covered the conventional excavation apparatus attached to the auger machine on the pile head part of the existing pile currently embed | buried under the ground. It is the front view which carried out the partial cross section which shows the condition which drilled to the lower end part of the existing pile currently embed | buried under the ground with the conventional excavation apparatus attached to the auger machine. It is the front view which carried out the partial cross section which shows the condition which is cutting the bump of the existing pile currently embed | buried under the ground with the conventional excavation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Excavator 10 ... Excavation head 11 ... Housing 12 ... Excavation blade 20 ... Excavation direction guide means 21 ... Roller 101 ... Leader 102 ... Auger machine 103 ... Casing 104 ... Spiral blade P ... Existing pile Q ... Cove S ... Ground U ... Roller unit

Claims (3)

A drilling device that can be lowered while rotating around the existing pile piled by a drilling blade provided at the lower end of the cylindrical casing, and is located above the drilling blade on the inner peripheral surface of the device The excavation direction guide means surrounding the side peripheral surface of the existing pile is provided, and the excavation direction guide means has a plurality of rotation axes set so as to be substantially parallel to the vertical axis of the casing. An excavator for pile removal, characterized in that the diameter of a virtual inscribed circle with which these rollers contact is set larger than the nominal outer diameter of the existing pile. A drilling device that can be lowered while rotating around the existing pile piled by a drilling blade provided at the lower end of the cylindrical casing, and is located above the drilling blade on the inner peripheral surface of the device , drilling direction guide means which surrounds the side peripheral surface of the existing pile are provided, the direction of drilling guide means, prior SL and consist flange structures extending to an inner peripheral surface in the circumferential direction of the casing, the inner diameter or inscribed drilling device for piles vent, wherein the diameter of the circle is set to be larger than the nominal outer diameter of the already Sonkui. The excavation apparatus for pile removal according to claim 1 or 2 , wherein the excavation direction guide means is arranged in two or more rows at intervals in the vertical direction along the axial direction of the casing.