JP6425267B2 - Construction method of rooted foundation using a rotating penetration pile and a rotating penetration pile - Google Patents

Description

  The present invention relates to a rotary penetration pile in which the bearing force (push-in resistance and pull-out resistance) is increased, and to a construction method of a rooted rotary penetration pile using the rotary penetration pile.

  In construction which adopts a pile as a foundation of civil engineering and construction work, in order to increase the bearing capacity of the pile, a method of forming an expanded rooting having a diameter larger than the diameter of the pile at the tip end of the pile is adopted. For example, excavate a hole for a pile whose diameter is the same as the diameter of the pile on the ground using a dedicated drilling device, and then expand the excavation so that the diameter of the hole near the pile tip is about twice the pile diameter. And stir-mix it with the soil on the ground, then pull up the dedicated drilling device from the hole for the pile and allow the pile to enter the hole for the pile before the hardenable fluid hardens, and harden the tip of the pile with the hardenable fluid There is known an expanded rooting method of penetrating and fixing in a mixture of water and earth and sand.

  However, in the above-described expanded rooting construction method, it is difficult to shorten the construction time because it is divided into the drilling process of the hole for the pile and the piling process of laying the pile in the hole for the pile There is a problem that a dedicated device is required.

  In order to solve the above problems, for example, using a rotary penetration pile provided with a spiral wing having an outer diameter twice to three times the pile diameter on the outer periphery of the pile tip portion and provided with a discharge hole of the hardenable fluid The rotational penetration pile is made to penetrate from the ground surface into the ground, and when the tip reaches the support layer in the ground, the spouting of the hardenable fluid from the discharge hole of the rotational penetration steel pipe pile is started. While rotating and moving up and down while repeating normal rotation and reverse rotation, while stirring and mixing earth and sand and hardenable fluid, it was penetrated to the final depth, and a cylindrical shape with the same diameter as the spiral wing was made around the steel pipe pile main body An expanded rooting method for forming a solidified mixture has been proposed (see Patent Document 1). The spiral wing has a role of promoting rotational penetration into the ground and a role of supporting force transmission to the supporting ground. With this construction method, it is possible to form an expanded rooting in the process of making a pile rotate into the ground without requiring a dedicated drilling device, and it is possible to shorten the construction time and reduce the construction cost.

  In addition, as another construction method, a plurality of auxiliary (expanded) excavating blades capable of protruding in the radial direction of the pile from the peripheral edge by appropriately spacing the peripheral edge of the spiral blade provided on the outer periphery of the pile tip along the peripheral direction Using a rotary penetrative pile in which the rotary penetrative pile is placed, this rotary penetrative pile is made to rotationally penetrate from the ground surface into the ground, and when its tip reaches near the upper end of the support layer in the ground, from the discharge hole of the rotary penetrative steel pipe pile Start the jet of the hardenable fluid to the outside, move it up and down while repeating normal rotation and reverse rotation, rotate and penetrate to the final depth while mixing soil and hardenable fluid with stirring, and around the steel pipe pile main body An enlarged rooting method has been proposed for forming a solidified mixture in the form of a column having the same diameter as that of an expanded cutting blade protruding from the periphery of a spiral wing (see Patent Document 2). In this construction method, as in the construction method using the above-mentioned rotary penetration pile, it is possible to form an expanded rooting in the process of making a pile rotate into the ground without requiring a dedicated drilling device, shortening construction time and construction cost In addition, the ground excavating size secured by the spiral wing is increased by the size by which the expanding digging blade protrudes, and the expanded rooting with a larger diameter than in the case of only the spiral wing can be achieved. It is possible to form.

JP, 2013-57194, A JP, 2013-19249, A

  In the former method, it is necessary to provide a spiral blade with a larger diameter in order to increase the bearing capacity of the pile, but doing so bulks when transporting the pile to the construction site and also rotates at the initial stage of rotational penetration into the ground There is a problem that penetration resistance increases.

  In the latter construction method, when making a pile rotate into the ground, the enlarged cutting edge is pushed by the soil around the ground and does not protrude from the peripheral edge of the spiral wing, and fits into the spiral wing, and reverses the rotary penetration pile to move upward. Since the extended cutting edge is pushed out by the soil around the ground and protrudes from the peripheral edge of the spiral wing when moving it, the initial resistance to rotational penetration into the ground is not much different from that of the spiral wing alone, There is a problem that it can not be confirmed in the ground that the extended cutting edge protrudes from the peripheral edge of the spiral wing.

  The present invention makes it possible to increase the bearing capacity of piles and to confirm that the extended cutting edge protrudes from the peripheral edge of the spiral wing in the ground, using the rotary penetration pile and the rotary penetration pile The purpose of the project is to provide a method of construction of a hardened foundation.

  The rotary penetration pile according to claim 1 of the present invention is a pile main body comprising an outer cylinder and an inner cylinder disposed in the tip portion of the outer cylinder in a state where the closed tip is exposed from the outer cylinder. A spiral wing provided along a circumferential surface near the tip of the inner cylinder exposed from the outer cylinder, and an enlarged digging blade provided on the spiral wing so as to be able to project radially outward of the pile main body; And a jet of a hardenable fluid provided on a circumferential surface of the inner cylinder, wherein the outer cylinder rotates the pile main body in a direction opposite to a direction in which the pile body is inserted into the ground. Is configured to be movable in the axial direction by a predetermined distance while rotating with respect to the shaft, and the enlarged digging blade is housed on the peripheral side of the spiral wing when the pile body is rotationally inserted into the ground, and the pile body is The outer cylinder rotates with respect to the inner cylinder when rotating in the direction opposite to the direction in which the rotary penetration is made. The outer cylinder is configured to protrude radially outward of the pile main body from the peripheral edge of the spiral wing, and the outer cylinder is rotated relative to the inner cylinder when the pile main body is rotated in a direction opposite to the rotational penetration direction. It is characterized in that movement by a predetermined distance in the axial direction is used to detect that the enlarged digging blade protrudes outward in the radial direction of the pile main body from the peripheral edge of the spiral wing.

  In the method of construction of a rooted foundation using a rotary penetration pile according to claim 10 of the present invention, the outer cylinder and the inside of the tip portion of the outer cylinder with the closed tip exposed from the outer cylinder And a spiral wing provided along the outer peripheral surface of the inner cylinder near the tip end of the inner cylinder exposed from the outer cylinder, and the spiral wing radially outward of the pile main body And an outlet for a hardenable fluid provided on a circumferential surface of the inner cylinder, the outer cylinder being in a direction to rotationally insert the pile main body into the ground It is configured to be able to move a predetermined distance in the axial direction while rotating with respect to the inner cylinder when it is rotated in the opposite direction to the above, and the enlarged digging blade is used to rotationally insert the pile body into the ground. Of the pile body and rotated in the direction opposite to the direction in which the pile body is inserted. The outer cylinder rotates with respect to the inner cylinder when protruding to project radially outward of the pile main body from the peripheral edge of the helical wing, and the jet port rotates and inserts the pile main body into the ground The circumference of the inner cylinder which is covered by the outer cylinder when being made to rotate, and which is rotated relative to the inner cylinder when it is rotated in the direction opposite to the direction in which the pile body is made to penetrate. Preparation step of arranging a hardenable fluid supply pipe in the pile main body using a rotary penetration pile provided at a surface location, and rotating the pile main body to drive the helical wing to a predetermined depth in the ground The outer cylinder is moved by a predetermined distance in the axial direction with respect to the inner cylinder at the time of the rotational penetration step of rotational penetration to the end and the initial stage of rotation of rotating the pile main body in the direction opposite to the direction of the rotational penetration. Use A confirmation step of confirming that the enlarged excavating blade protrudes outward in a radial direction of the pile main body from a peripheral edge of the spiral wing by rotation of the outer cylinder with respect to the inner cylinder; and after the confirmation step, rotating the pile main body While rotating in the direction opposite to the penetrating direction and pulling up from the predetermined depth to the predetermined position, the curable fluid is supplied from the curable fluid supply pipe through the spout which is not covered by the outer cylinder. And rotating the step of excavating the ground around the spiral blade with the expanding blade, and repeating the step of rotating penetration and the step of rotating pulling between the predetermined position and the predetermined depth. In the meantime, the spiral fluid, the earth and sand excavated by the enlarged cutting blade, and the hardenable fluid ejected from the jet nozzle are stirred and mixed.

  According to the present invention, the bearing capacity of the pile can be increased, and when the pile body is rotated in the direction opposite to the direction in which the pile is rotationally inserted into the ground, the outer cylinder is axially displaced from the inner cylinder by a predetermined distance. Since it is configured to detect that the enlarged cutting blade protrudes radially outward of the pile main body from the peripheral edge of the spiral wing by using movement, the protruding of the enlarged cutting blade is confirmed with a very simple configuration. It is possible.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Example of the rotation penetration pile of this invention, (a) is a schematic perspective view which shows the state which the expansion excavation blade settled in the periphery of a helical wing, (b) is an expansion excavation blade being a peripheral edge of a helical wing. It is a schematic perspective view which shows the state which protruded to the radial direction outer side of a pile main body from them. FIG. 1A is a detailed view of the rotary penetration pile in the state shown in FIG. 1A, where (a) is a partially cut vertical sectional view partially omitted, (b) is a partially omitted plan view, and (c) is an outer cylinder and jet It is a partial side view showing a relation with an exit. It is a detailed view of the rotation penetration pile in the state shown in FIG. 1 (b), (a) is a partially cut vertical sectional view partially omitted, (b) a plan partially omitted, (c) an outer cylinder and a jet It is a partial side view showing a relation with an exit. It is a figure showing a 2nd example of a rotation penetration pile of the present invention, and (a) is a half cutting vertical sectional view in the state where an expansion excavation blade was settled in a peripheral edge of a spiral wing, (b) is partial omission in the same state FIG. Fig. 4 is a view in which the enlarged cutting edge of the rotary penetration pile shown in Fig. 4 protrudes outward in the radial direction of the pile main body from the peripheral edge of the spiral blade, where (a) is a partially cut vertical sectional view with the part omitted in the same state, b) is a partially omitted plan view in the same state. BRIEF DESCRIPTION OF THE DRAWINGS It is process explanatory drawing which shows 1st Example of the construction method of the rooted foundation which uses the rotation penetration pile of this invention, (a) is before the front-end | tip part of a rotation penetration pile reaches the support layer in the ground. (B) shows a state in which the tip of the rotary penetration pile has reached the bottom of the support layer in the ground, and (c) shows the support by rotating the rotary penetration pile in the opposite direction to that in rotational penetration Figure showing a state where pulling is started from the bottom of the layer, (d) shows a state where the rotary penetration pile is pulled to the top of the support layer, (e) shows a state where the tip of the rotary penetration pile returns to the bottom of the support layer FIG. It is a figure which shows 3rd Example of the rotation penetration pile of this invention, (a) is the partially-omitted top view in the state which the expansion excavation blade settled in the peripheral side of a helical wing, (b) is an expansion excavation blade It is the partially omitted top view in the state protruded in the radial direction outer side of a pile main body from the periphery of a helical wing. FIG. 7 shows a first modification of the rotary penetration pile according to the present invention, wherein (a) is a partially omitted plan view in a state in which the enlarged cutting edge is accommodated on the peripheral side of the spiral wing, (b) is the enlarged cutting edge These are the partially omitted top views in the state which protruded to the radial direction outer side of a pile main body from the periphery of a helical wing. 7 is a second modification of the rotary penetration pile of the present invention shown in FIG. 7, wherein (a) is a partially omitted plan view in a state in which the enlarged cutting edge is accommodated on the peripheral side of the spiral blade, (b) is the enlarged cutting edge These are the partially omitted top views in the state which protruded to the radial direction outer side of a pile main body from the periphery of a helical wing. It is a figure showing the 4th example of a rotation penetration pile of the present invention, and (a) is the top view which partially omitted in the state where a penetration part was closed, while an extended excavation blade fits in the peripheral side of a spiral wing. b) is the top view which partially omitted in the state in which the penetration part was opened, while an expansion excavation blade protrudes to the radial direction outer side of a pile main body from the periphery of a helical wing | blade. It is a figure which shows the 5th Example of the rotation penetration pile of this invention, (a) is the top view which partially abbreviate | omitted in the state which the expansion excavation blade settled in the peripheral side of a helical wing, (b) is an expansion excavation blade It is the partially omitted top view in the state protruded in the radial direction outer side of a pile main body from the periphery of a helical wing. 11 is a modification of the rotary penetration pile of the present invention shown in FIG. 11, where (a) is a partially omitted plan view in a state in which the enlarged cutting blade is accommodated on the peripheral side of the spiral blade, (b) is a spiral drawing of the enlarged cutting blade It is the partially omitted top view in the state protruded in the radial direction outer side of a pile main body from the periphery of a wing | blade. It is a figure showing a 6th example of a rotation penetration pile of the present invention, and (a) is a top view partially omitted in the state where a penetration part was closed, while an extended excavation blade fits in the peripheral side of a spiral wing. ) Is a plan view partially omitted in a state in which the penetrating portion is open, while the enlarged drilling blade protrudes radially outward of the pile main body from the peripheral edge of the spiral wing. Explanatory drawing explaining the state from which the excavated earth and sand and the hardenable fluid flow from the one surface side of the spiral wing to the other surface side or the other surface side through the penetration part, (a 11 is an explanatory view of the flow state of excavated earth and sand and the hardenable fluid in the penetration shown in FIG. 7, FIG. 8 or FIG. 11, and (b) is excavated in the penetration shown in FIG. It is explanatory drawing of the flowing state of earth and sand and a hardenable fluid.

  The outline of a first embodiment of the rotary penetration pile of the present invention will be described with reference to FIGS. 1 (a) and 1 (b). The rotary penetration pile A of this embodiment is a steel pipe disposed in the tip portion of the outer cylinder 11 in a state in which the outer cylinder 11 made of steel pipe and the tip closed by the bottom lid 13 are exposed from the outer cylinder 11 In the circumferential direction of the pile main body 10 having the inner cylinder 12 and the spiral blade 20 of approximately one turn provided along the outer peripheral surface of the inner cylinder 12 exposed from the outer cylinder 11 near the tip of the inner cylinder 12 Two expansive drilling blades 30 which can be projected radially outward of the pile main body 10 and arranged with an opening angle of ° and a jet 40 of a hardenable fluid provided on the circumferential surface of the inner cylinder 12 , And a tip digging blade 50 disposed on the bottom lid 13. When the pile body 10 is rotated in the ground in the direction opposite to the direction in which the pile body 10 is rotationally propelled (in the direction of pulling up from the ground), the outer cylinder 11 rotates a predetermined angle with the inner cylinder 12 at the initial stage of rotation Move in the direction (upward by a predetermined distance). From the initial stage of rotation in the direction opposite to the direction of rotational propulsion into the ground, the outer cylinder 11 and the inner cylinder 12 rotate integrally. In the rotary penetration pile A of this embodiment, at the initial stage of rotation, the diameter of the pile main body 10 is increased from the peripheral edge of the spiral wing 20 by using the outer cylinder 11 rotating at a predetermined angle with respect to the inner cylinder 12. Of the outer cylinder 11 by moving the outer cylinder 11 in the axial direction by a predetermined distance with respect to the inner cylinder 12 by the rotation of the outer cylinder 11 with respect to the inner cylinder 12. It detects that it has protruded to the In addition, the outer cylinder 11 is added according to the penetration depth to the ground of the rotational penetration pile A at the time of construction. A hardenable fluid has fluidity at the time of construction and hardens with the passage of time after construction. For example, it is a milk-like one in which cement or a ground solidifying material is dissolved with water, or a mortar in which sand is added thereto. Etc.

  As shown in FIG. 1A, the tip of the outer cylinder 11 is cut in a substantially spiral shape, and the outer peripheral surface of the inner cylinder 12 near the tip is cut away from the outer cylinder 11 via the notch 14. It is exposed. The notch 14 is provided with a step 14a which is engaged with the one end 20a of the spiral blade 20 in the state shown in FIG. Moreover, the recessed part 14b which the inner end part 32a (refer FIG.2 (b)) of the support piece 32 which comprises the expansion cutting blade 30 accommodates is provided.

  As shown in FIGS. 2 (a) and 3 (a), the inside of the inner cylinder 12 is divided into upper and lower two rooms 15a and 15b via a partition plate 15, and the inner wall of the lower room 15b is The jet nozzle 40 is provided, and a receiving pipe 61 for detachably receiving the tip portion of the curable fluid supply pipe 60 in the upper chamber 15a is provided. The lower end of the receiving pipe 61 is connected to a hole 15 c provided in the central portion of the partition plate 15. The curable fluid is supplied from the curable fluid supply pipe 60 to the lower chamber 15 b through the receiving pipe 61 and the hole 15 c, and the curable fluid is spouted from the spout 40 outward in the radial direction of the pile main body 10. A plurality of elastic rings 62 (three in FIG. 2A and FIG. 3A) are disposed on the inner peripheral surface of the receiving pipe 61 at appropriate intervals in the axial direction, and a curable fluid supply pipe is provided. The hardening fluid is prevented from leaking from the gap between 60 and the receiving pipe 61.

  As shown in FIG. 2 (a) and FIG. 3 (a), the inner peripheral surface of the tip end portion of the outer cylinder 11 and the outer peripheral surface of the inner cylinder 12 covered with the inner peripheral surface The threaded portion 16 and the threaded portion 17 having the same pitch are provided, and the inner cylinder 12 is screwed into the tip portion of the outer cylinder 11 via the threaded portions 16 and 17. On the inner peripheral surface of the outer cylinder 11, a stopper 18 is provided at a position near the screw portion 16, and when the outer cylinder 11 moves in the axial direction as the outer cylinder 11 rotates with respect to the inner cylinder 12. The stopper 18 abuts against the screw portion 17 of the inner cylinder 12 so that the outer cylinder 11 can not move further. In this embodiment, the outer cylinder 11 is rotated once with respect to the inner cylinder 12 by the stopper 18 and the outer cylinder 11 is set so as to stop there when it is moved by one pitch in the axial direction.

  The spiral wing 20 has an outer diameter twice to three times the outer diameter of the outer cylinder 11. While the rotary penetration pile A (pile main body 10) is rotated (positively rotated) in the direction to rotationally insert the ground into the ground, the one end 20a of the spiral wing 20 and the step 14a of the notch 14 The stopped state is maintained (see FIG. 1A) to prevent the outer cylinder 11 from rotating relative to the inner cylinder 12. Therefore, while the pile main body 10 is rotated forward and rotationally inserted into the ground, the outer cylinder 11 and the inner cylinder 12 integrally rotate and penetrate into the ground.

  On the other hand, when the pile body 10 is rotated (reversely rotated) in the direction opposite to the direction in which the pile body 10 is inserted into the ground, the outer cylinder 11 makes one rotation with respect to the inner cylinder 12 at the initial stage of the rotation. The retaining stopper 18 prevents movement of the outer cylinder 11 relative to the inner cylinder 12 by more than one pitch, and thereafter the outer cylinder 11 and the inner cylinder 12 are integrated. And rotate and retreat from the ground (pulled up).

As shown in FIG. 2 (a), FIG. 3 (a), etc., the enlarged cutting blade 30 has a cutting blade 31 extending in the axial direction of the pile main body 10 and the cutting blade 31 as the spiral blade 20. And a pair of support pieces 32 to be attached. The pair of support pieces 32 sandwich the surface portion of the spiral wing 20, and the inner end side closer to the inner cylinder 12 is pivotally attached to the spiral wing 20 by a pivot 33 axially penetrating the surface portion of the spiral wing 20. The cutting edge piece 31 is fixed (welded) to the outer end of the peripheral side of the spiral wing 20 of the pair of support pieces 32 . The cutting blade piece 31 swings (rotates) with respect to the spiral wing 20 with the pivot 33 as a fulcrum, and can project radially outward of the pile main body 10 from the peripheral edge of the spiral wing 20.

  When the pile main body 10 is rotated forward to be inserted into the ground, the frictional force of the ground acting on the spiral blade 20 is the expanded cutting blade 30 as shown by the arrow B in FIG. 2 (b). Acts on the peripheral side of the spiral wing 20. For this reason, as shown in FIGS. 2 (b) and 2 (c), in the enlarged cutting blade 30, the inner end portion 32a of the support piece 32 stops in the recess 14b provided in the notch 14 of the outer cylinder 11. The cutting blade 31 is accommodated on the peripheral side of the spiral blade 20. On the other hand, when pulling up the pile main body 10 from the ground in reverse, the frictional force of the ground acting on the spiral blade 20 is as shown by arrow C in FIG. It acts in a direction of pushing radially outward from the peripheral edge of the pile main body 10 from the peripheral edge 20. At the initial stage of the reverse rotation, the outer cylinder 11 is rotated relative to the inner cylinder 12, and the support piece 32 has an outer end portion 32a, as shown in FIGS. 1 (b) and 3 (b). The excavating blade 31 is pushed by the recess 14 b of the notch 14 of the cylinder 11 and rotates around the pivot 33, and the digging blade piece 31 protrudes outward in the radial direction of the pile main body 10 from the peripheral edge of the spiral wing 20. That is, at the initial stage of the reverse rotation, a pushing force from the outer cylinder 11 to the radially outer side of the pile main body 10 acts on the enlarged cutting blade 30. The friction between the ground and the pushing force of the outer cylinder 11 combine to ensure that the cutting edge 31 of the enlarged cutting edge 30 projects outward in the radial direction of the pile body 10.

  When the enlarged excavating blade 30 rotates and enters the ground by rotating the pile main body 10 forward, the enlarged excavating blade 30 is accommodated on the peripheral side of the spiral blade 20, and therefore hardly causes rotational penetration resistance. In addition, when the pile body 10 is reversely rotated in the ground, the cutting blade piece 31 of the enlarged cutting blade 30 protrudes outward in the radial direction of the pile body 10 to enlarge the digging area. Therefore, when the pile main body 10 is repeatedly moved up and down in the ground by rotating forward and reverse repeatedly, it is possible to dig and soften more soil around the spiral blade 20 than in the case of the spiral blade 20 alone.

As shown in FIGS. 1 (a) and 1 (b) etc., a mark 70 is attached by paint or the like on the outer peripheral surface of the curable fluid supply pipe 60 located at the upper end of the pile head of the outer cylinder 11. ing. When the outer cylinder 11 is moved upward in the axial direction by one pitch of the screw portions 16 and 17 with respect to the inner cylinder 12 , the mark 70 is hidden in the pile head of the outer cylinder 11. This is a result of the outer cylinder 11 rotating one turn with respect to the inner cylinder 12, and as described above, the diameter of the pile main body 10 from the peripheral edge of the spiral blade 20 is the enlarged drilling blade 30 by one rotation of the outer cylinder 11. Protrudes outward in the direction. Therefore, by observing that the mark 70 is hidden in the pile head of the outer cylinder 11, it is possible to detect that the enlarged cutting blade 30 protrudes outward in the radial direction of the pile main body 10.

  In this embodiment, when the pile main body 10 is reversely rotated in the ground, the outer cylinder 11 is moved axially upward by one pitch of the screw portions 16 and 17 with respect to the inner cylinder 12 at the initial stage of the rotation. To indicate that the mark 70 is provided on the outer peripheral surface of the hardenable fluid supply pipe 60 in order to detect that the enlarged cutting blade 30 protrudes outward in the radial direction of the pile main body 10 from the peripheral edge of the spiral wing 20 However, it is not limited to this. For example, a change in height of the pile head may be measured by placing a ruler or the like on the upper end of the pile head of the outer cylinder 11 exposed from the ground.

  Although the said spout 40 is comprised, for example from a non-return valve etc., although the hardenable fluid can be spouted to the excavated earth and sand in the ground from the said room 15b, the excavated earth and sand in the ground is a room It has a function to prevent it from flowing into 15b. The jet nozzle 40 is located between one end 20a and the other end 20b of the spiral wing 20 on the circumferential surface of the inner cylinder 12, as shown in FIGS. 1 (b) and 3 (c). The jet nozzle 40 is covered and protected by the outer cylinder 11 (the outer cylinder 11 is closed) as shown in FIG. 1 (a) and FIG. 2 (c) at the time of forward rotation in which the pile body 10 is rotationally inserted into the ground. When the pile body 10 is pulled up from the ground, as shown in FIG. 1 (b) and FIG. 3 (c), it is not covered by the outer cylinder 11 (the outer cylinder 11 opens), and the curable fluid can be jetted It becomes.

  As described above, according to the rotary penetration pile A of the first embodiment, the supporting force can be increased by the enlarged digging blade 30, and the hardenable flow located at the upper end of the pile head of the outer cylinder 11 A mark 70 is attached to a point on the outer peripheral surface of the body supply pipe 60, and by observing the mark 70, the enlarged cutting blade 30 protrudes radially outward of the pile main body 10 from the peripheral edge of the spiral wing 20 in the ground. Can be detected. Further, the mark 70 as a detection means can be easily attached by paint or the like, and the cost can be reduced. Further, when the pile body 10 is reversely rotated in the ground, the outer cylinder 11 rotates relative to the inner cylinder 12 at the initial stage of the rotation, and the enlarged cutting blade 30 is made from the peripheral edge of the spiral wing 20 radially outward of the pile body 10 The extruding force acts, and the extruding force and the frictional force acting on the spiral blade 20 from the ground (see arrow C in FIG. 3B) combine to make the cutting blade 31 radially outward of the pile body 10 It can be made to project reliably. Furthermore, since the spout 40 is covered by the outer cylinder 11 and protected from the earth and sand around the spiral wing 20 when the pile body 10 is rotated forward and rotated into the ground, the spout 40 is configured A general purpose product can be used as a check valve, and cost reduction can be achieved. Furthermore, when the pile main body 10 is reversely rotated in the ground, the outer cylinder 11 is opened, and the hardened fluid supplied from the hardenable fluid supply pipe 60 without any trouble is excavated in the soil around the spiral wing 20 You can spout towards the

  Fig.4 (a), (b), FIG. 5 (a), (b) has shown 2nd Example of the rotation penetration pile of this invention. In the figure, the same reference numerals are given to the same parts as the parts shown in FIGS. 1 (a) and 1 (b), 2 (a), 2 (b) and 2 (c) and 3 (a), 3 (b) and 3 (c). And the detailed description is omitted.

  In the rotary penetration pile Aa of the second embodiment, the mechanism for causing the enlarged excavating blade 30 to protrude outward in the radial direction of the pile main body 10 is different from the rotary penetration pile A of the first embodiment described above, Is the same. The protruding mechanism is composed of a pin 80 provided on the outer cylinder 11 side and a groove 81 provided on the enlarged cutting blade 30 side engaged with the pin 80 in a slidable manner. When the outer cylinder 11 rotates relative to the inner cylinder 12 at the initial stage of reverse rotation, the pin 80 slides in the groove 81 to rotate the enlarged cutting blade 30 about the pivot 33 as a pivot. It projects outward in the radial direction of the main body 10. The pin 80 is attached to a substantially fan-shaped support projection 82 provided on the outer peripheral surface of the tip end portion of the outer cylinder 11 corresponding to the pair of enlarged cutting blades 30 so as to extend in the axial direction of the outer cylinder 11 Be The groove portion 81 is provided in the inner end portion of the support piece 32 on the surface (upper surface) side of the spiral wing 20 of the pair of support pieces 32 so as to extend in the direction of the pivot axis 33.

  When the pile main body 10 is rotated forward to be inserted into the ground, the frictional force of the ground acting on the spiral blade 20 is the expanded cutting blade 30 as shown by the arrow D in FIG. 4 (b). Of the enlarged cutting blade 30 is accommodated on the peripheral side of the spiral blade 20. On the other hand, when pulling up the pile main body 10 from the ground in reverse, the frictional force of the ground acting on the spiral blade 20 is as shown by arrow E in FIG. 5 (b). It acts in a direction of pushing radially outward from the peripheral edge of the pile main body 10 from the peripheral edge 20. At the initial stage of the reverse rotation, the outer cylinder 11 rotates with respect to the inner cylinder 12 and the pin 80 slides in the groove 81 along with the rotation, whereby the enlarged cutting blade 30 is pivoted on the pivot 33 as a fulcrum. A force acts to cause the pile body 10 to project radially outward by rotating it. The enlarged cutting blade 30 has a force of friction from the ground and a force from the outer cylinder 11 transmitted through the pin 80 and the groove 81 to ensure that the cutting blade 31 is on the radially outer side of the pile body 10 Project to

  Similarly to the rotary penetration pile A of the first embodiment described above, the rotary penetration pile Aa of the second embodiment can also increase the supporting force by the enlarged digging blade 30, and observe the mark 70. Thus, it is possible to detect that the enlarged drilling blade 30 protrudes radially outward of the pile main body 10 from the peripheral edge of the spiral wing 20 in the ground. Further, at the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged drilling blade 30 can be reliably protruded to the radially outer side of the pile main body 10.

  In the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged excavating blade 30 is moved from the peripheral edge of the spiral wing 20 by utilizing the rotation of the outer cylinder 11 with respect to the inner cylinder 12. The mechanism for projecting radially outward is not limited to the mechanisms of the two embodiments shown in FIGS. 1 (a) and (b) to 5 (a) and 5 (b).

  Next, with reference to FIGS. 6 (a) to 6 (e), one embodiment of a method of constructing a rooted foundation using the rotary penetration pile of the present invention will be described. In the construction method of the present embodiment, the rotary penetration pile A of the first embodiment shown in FIGS. 1 (a), (b) to 3 (a), (b), (c) is used. In the figure, the same parts as the parts shown in FIG. 1 (a), (b) to FIG. 3 (a), (b) and (c) are assigned the same reference numerals and detailed explanations thereof will be omitted.

  First, the tip portion of the hardenable fluid supply pipe 60 is inserted into the receiving pipe 61 (see, for example, FIG. 2A) before the rotary penetration pile A is rotationally penetrated into the ground. After this preparation process, the process proceeds to the rotational penetration process shown in FIGS. 6 (a) and 6 (b).

  Fig.6 (a) shows the state before the front-end | tip part of rotation penetration pile A reaches | attains the support layer S in the ground in a rotation penetration process. As shown in the figure, the pile main body 10 is rotationally driven (positively rotated) by a ground driving machine (not shown) on which the rotary drive is mounted, and the screwing action (propulsive force) of the spiral wing 20 is utilized. Penetration into the ground. At the time of this rotational penetration, the pile body 10 penetrates while digging the ground while the tip digging blade 50 digging in, so that the pile body 10 smoothly penetrates even when the ground is hard. In addition, when the ground is not very hard, the pile main body 10 can be penetrated into the ground without any trouble even if the tip digging blade 50 is not provided.

  In the rotational penetration step, as shown in FIG. 6 (b), the tip end portion of the pile body 10 is scheduled to locate the lower end of the rooted body F (see FIGS. 6 (c) to 6 (e)) in the support layer S. Continue until it reaches the depth of (bottom of support layer S). When the bottom of the support layer S is reached, a mark 70 is provided by paint or the like on the outer peripheral surface of the hardenable fluid supply pipe 60 located at the upper end of the pile head of the outer cylinder 11. In the rotational penetration process, the enlarged drilling blade 30 is accommodated on the peripheral side of the spiral blade 20 by the frictional force acting on the spiral blade 20 from the soil around the spiral blade 20, and the enlarged drilling blade 30 is a rotational intrusion of the pile body 10 It does not become resistance.

  Since the outer cylinder 11 rotates with respect to the inner cylinder 12 at the initial stage of rotation in which the pile main body 10 is rotated (reversely rotated) in the direction opposite to the rotational penetration after the above-mentioned rotation penetration process, enlargement is performed using this The excavating blade 30 is pushed outward from the peripheral edge of the spiral blade 20 in the radial direction of the pile main body 10, and the outer cylinder 11 is moved in the axial direction by a predetermined distance with respect to the inner cylinder 12 along with this rotation. It is confirmed that the enlarged cutting blade 30 protrudes outward in the radial direction of the pile body 10. That is, in this confirmation step, the excavating blade 30 is moved from the peripheral edge of the spiral wing 20 radially outward of the pile main body 10 by utilizing the movement of the outer cylinder 11 in the axial direction while rotating with respect to the inner cylinder 12. While extruding, it is confirmed that the enlarged drilling blade 30 protrudes radially outward of the pile main body 10. In this embodiment, the mark 70 on the outer peripheral surface of the hardenable fluid supply pipe 60 located at the upper end of the pile head of the outer cylinder 11 located on the ground surface is hidden in the pile head of the outer cylinder 11 It is confirmed that the enlarged cutting blade 30 protrudes outward in the radial direction of the pile main body 10 by observing the (see FIG. 6C).

  In the confirmation step, when the mark 70 on the outer peripheral surface of the hardenable fluid supply pipe 60 is hidden in the pile head of the outer cylinder 11, the enlarged cutting blade 30 is piled from the peripheral edge of the spiral wing 20 by the outer cylinder 11. Since it indicates that it has been projected outward in the radial direction of 10 and that the outer cylinder 11 has opened without covering the spout 40, the rotary pull-up process of pulling up the pile body 10 further in reverse in the support layer S after this confirmation process. Move to In the rotational pulling process, as shown in FIG. 6C, the hardenable fluid is ejected from the ejection port 40 while the pile main body 10 is reversely rotated. The pile body 10 moves upward from the bottom of the support layer S, and excavates the ground around the spiral wing 20 with an enlarged cutting blade 30 projecting radially outward of the pile body 10 in the process of the movement. That is, while carrying out the expanded excavation, the excavated earth and sand and the ejected curable fluid are stirred and mixed.

  The said rotation pulling-up process is performed until the front-end | tip part of the pile main body 10 reaches the planned depth (upper part of the support layer S) where the upper end of the rooted body F is located, as shown in FIG.6 (d). When the tip portion of the pile main body 10 reaches the upper portion of the support layer S, the pile main body 10 is positively rotated, but the positive rotation of the pile main body 10 is performed at the portion of the support layer S already excavated. The frictional force of the ground pressing the blade 30 against the peripheral edge of the spiral wing 20 is weak, and the enlarged cutting blade 30 still protrudes radially outward of the pile body 10. Enlargement drilling and agitation mixing are performed while rotating the pile main body 10 forward in the support layer S. This rotational penetration, expansion drilling and agitation mixing are performed until the tip portion of the pile body 10 reaches the bottom of the support layer S, as shown in FIG. 6 (e).

  When the tip end portion of the pile body 10 reaches the bottom of the support layer S, the process proceeds from the rotational penetration process (see FIG. 6E) to the rotational pulling process (see FIG. 6D). After the rotational penetration process, the pile body 10 is moved up and down a plurality of times in the support layer S by repeating the rotational pull-up process and the expansion drilling and agitation mixing. As a result, the earth and sand excavated by the spiral blade 20 and the enlarged cutting blade 30 are stirred and mixed using the hardenable fluid ejected from the jet 40, the spiral blade 20 and the enlarged cutting blade 30. Although this stirring and mixing varies depending on the properties of excavated earth and sand, and the properties of the hardenable fluid to be used, for example, after the rotation penetration process, the stirring and mixing by the vertical movement of the pile body 10 is repeated ten times.

  As described above, the rooting body F obtained by solidifying the excavated earth and sand in the ground with the hardenable fluid is completed in the support layer S.

  7 (a) and 7 (b) show a third embodiment of the rotary penetration pile of the present invention. In the figure, the same reference numerals are given to the same parts as the parts shown in FIGS. 1 (a) and 1 (b), 2 (a), 2 (b) and 2 (c) and 3 (a), 3 (b) and 3 (c). And the detailed description is omitted.

  In the rotary penetration pile Ab of the third embodiment, a pair of square through holes serving as a through portion that causes the spiral wing 20 to communicate between the one surface side (front surface side) and the other surface side (back surface side) 21 is provided, and this point is different from the rotary penetration pile A of the first embodiment described above, and the other parts are the same. As shown in FIG. 14 (a), when rotating the penetrating penetration pile Ab forward and reversely rotate and moving the tip portion of the pile body 10 up and down a plurality of times within the support layer S (see FIG. 6), Earth and sand excavated by the spiral blade 20 and the enlarged drilling blade 30 through the through hole 21 and the hardenable fluid jetted from the jet nozzle 40 are from the front surface side to the rear surface side of the spiral blade 20 or from the rear surface side to the front surface side Flow to The agitation mixing by the flow of the earth and sand and the hardenable fluid performed through the through holes 21 is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30 so that the agitation mixing of the earth and sand and the hardenable fluid is performed. It becomes possible to form the rooting body F (see FIG. 6) in which soil and soil and a hardenable fluid are uniformly mixed. Incidentally, even in the case of the rotary penetration pile Ab of the third embodiment, the supporting force can be increased by the enlarged digging blade 30 as in the case of the rotary penetration pile A of the first embodiment described above, and the mark 70 (see FIG. By observing 1 (a) or the like), it can be detected that the enlarged cutting blade 30 protrudes from the peripheral edge of the spiral wing 20 to the outside in the radial direction of the pile main body 10 in the ground. Further, at the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged drilling blade 30 can be reliably protruded to the radially outer side of the pile main body 10.

  Fig.8 (a), (b) has shown the 1st modification of the rotation penetration pile Ab of the said 3rd Example. 1 (a), (b), 2 (a), 2 (b), 2 (c), 3 (a), 3 (b), 2 (c), 7 (a), 7 (b). The same reference numerals are given to the same parts as the parts shown in and the detailed description thereof will be omitted.

  In rotation penetration pile Ac of the 1st modification, a pair of notch 21a which notched a part of periphery of said spiral wing 20 is provided as said penetration part. Also in the rotary penetration pile Ac of the first modification, as shown in FIG. 14 (a), the earth and sand excavated by the spiral wing 20 and the expanding digging blade 30 are spouted from the spout 40 through the notch 21a. The curable fluid flows from the front surface side to the back surface side of the spiral blade 20 or from the back surface side to the front surface side, and the stirring and mixing by this flow is added to the stirring and mixing using the spiral blade 20 and the enlarged cutting blade 30. The stirring and mixing of the soil and the hardenable fluid is further facilitated, and it becomes possible to form the rooted body F in which the soil and the hardenable fluid are uniformly mixed.

  Fig.9 (a), (b) has shown the 2nd modification of the rotation penetration pile Ab of the said 3rd Example. 1 (a), (b), 2 (a), 2 (b), 2 (c), 3 (a), 3 (b), 2 (c), 7 (a), 7 (b). The same reference numerals are given to the same parts as the parts shown in and the detailed description thereof will be omitted.

  In the rotary penetration pile Ad of the second modification, the spiral wing 20 is provided with a pair of square through holes 21b as the through portion, and a guide portion 22 is provided on one end side in the long side direction of the through hole 21b. There is. The guide portion 22 is formed, for example, by bending a part of a cut-and-raised portion generated when forming the through hole 21 b at an appropriate angle on the back surface side of the spiral wing 20. As shown in FIG. 14 (b), the guide portion 22 guides the earth and sand excavated by the spiral blade 20 and the enlarged drilling blade 30 and the curable fluid ejected from the jet port 40 to the through hole 21 b, The flow of soil and hardenable fluid from the surface side to the back surface side of the spiral wing 20 or from the back surface side to the surface side through the through holes 21b is smoothened. Also in the rotary penetration pile Ad of the second modification, the agitation mixing by the flow of the soil and the hardenable fluid performed through the through hole 21b is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30, The stirring and mixing of the soil and the hardenable fluid is further facilitated, and it becomes possible to form the rooted body F in which the soil and the hardenable fluid are uniformly mixed.

  Fig.10 (a), (b) has shown 4th Example of the rotation penetration pile of this invention. In the figure, the same reference numerals are given to the same parts as the parts shown in FIGS. 1 (a) and 1 (b), 2 (a), 2 (b) and 2 (c) and 3 (a), 3 (b) and 3 (c). And the detailed description is omitted.

  In the rotary penetration pile Ae of the fourth embodiment, the spiral wing 20 is provided with a pair of square through holes 21c as a through portion for communicating the front surface side and the rear surface side, and the support piece of the enlarged cutting blade 30 The pair of through holes 21c can be opened and closed by means of 32, and this point is different from the rotary penetration pile A of the first embodiment described above, and the other parts are the same. When rotating the penetrating penetration pile Ae forward and reversely rotating to move the tip end portion of the pile body 10 up and down a plurality of times in the support layer S, as shown in FIG. 14A, through the through hole 21c. The earth and sand excavated by the spiral blade 20 and the enlarged drilling blade 30 and the hardenable fluid ejected from the jet nozzle 40 flow from the front surface side to the rear surface side of the spiral blade 20 or from the rear surface side to the front surface side. The agitation mixing by the flow of the earth and sand and the hardenable fluid performed through the through holes 21c is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30, thereby the agitation mixing of the earth and sand and the hardenable fluid is performed. It becomes possible to form the rooting body F in which soil and soil and a hardenable fluid are uniformly mixed. In the fourth embodiment, unlike the third embodiment in which the through hole 21 is also provided, the through hole 21c can be opened and closed by the support piece 32, and the rotation penetration pile Ae is rotated forward to rotate in the ground. At the time of penetration, as shown in FIG. 10A, the through hole 21 c is closed by the support piece 32 of the enlarged cutting blade 30 accommodated on the peripheral side of the spiral wing 20. Therefore, it is possible to prevent the ground reaction force from leaking through the through hole 21c during the rotational penetration, and to prevent the reduction of the rotational propulsive force into the ground due to the provision of the through hole 21c. As shown in FIG. 10 (b), when the through hole 21c is pulled up from the ground by rotating the rotary penetration pile Ae in the reverse direction, the through hole 21c extends in the radial direction of the pile main body 10 from the peripheral side of the spiral wing 20. It is opened by the support piece 32 of the projecting enlarged cutting blade 30. Incidentally, even in the case of the rotary penetration pile Ae of the fourth embodiment, in the same manner as the rotary penetration pile A of the first embodiment described above, the supporting force can be increased by the enlarged digging blade 30, and the mark 70 (see FIG. By observing 1 (a) or the like), it can be detected that the enlarged cutting blade 30 protrudes from the peripheral edge of the spiral wing 20 to the outside in the radial direction of the pile main body 10 in the ground. Further, at the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged drilling blade 30 can be reliably protruded to the radially outer side of the pile main body 10.

  Fig.11 (a), (b) has shown 5th Example of the rotation penetration pile of this invention. In the figure, the same parts as the parts shown in FIG. 4A, FIG. 4B, FIG. 5A, and FIG. 5B are assigned the same reference numerals and detailed explanations thereof will be omitted.

  In the rotary penetration pile Af of the fifth embodiment, the spiral wing 20 is provided with a pair of square through holes 21 d as a through portion for communicating the surface side and the back side with each other, and this point is the above-described fifth Although it differs from the rotation penetration pile Aa of 2 Examples, it is the same about parts other than this. It is the same as the rotation penetration pile Ab of the third embodiment described above in that the through hole 21d is provided. When rotating the penetrating penetration pile Af forward and reversely rotating to move the tip end portion of the pile body 10 up and down a plurality of times in the support layer S, as shown in FIG. 14A, through the through hole 21d. The earth and sand excavated by the spiral wing 20 and the enlarged drilling blade 30 and the hardenable fluid jetted from the jet port 40 flow from the front side to the rear side of the spiral wing 20 or from the rear side to the front side. The agitation mixing by the flow of the earth and sand and the hardenable fluid performed through the through holes 21d is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30, thereby the agitation mixing of the earth and sand and the hardenable fluid is performed. It becomes possible to form the rooting body F in which soil and soil and a hardenable fluid are uniformly mixed. In addition, even in the case of the rotary penetration pile Af of the fifth embodiment, as in the case of the rotary penetration pile A of the first embodiment described above, the supporting force can be increased by the enlarged digging blade 30, and the mark 70 (FIG. By observing, etc.), it can be detected in the ground that the enlarged cutting blade 30 protrudes from the peripheral edge of the spiral wing 20 radially outward of the pile main body 10. Further, at the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged drilling blade 30 can be reliably protruded to the radially outer side of the pile main body 10.

  12 (a) and 12 (b) show modifications of the rotary penetration pile Af of the fifth embodiment. In the figure, the same parts as those shown in FIGS. 4 (a) and 4 (b), 5 (a) and 5 (b) and FIGS. 11 (a) and 11 (b) are indicated by the same reference numerals. Omit.

  In the rotary penetration pile Ag of this modification, the spiral wing 20 is provided with a pair of square through holes 21 e as the through portion, and a guide portion 22 a is provided on one end side in the long side direction of the through holes 21 e. Similar to the guide portion 22 (see FIG. 9), the guide portion 22a may be bent at an appropriate angle on the back surface side of the spiral wing 20, for example, by bending a part of the cut-and-raised portion formed when forming the through hole 21e. It is formed by As shown in FIG. 14 (b), the guide portion 22 a guides the earth and sand excavated by the spiral blade 20 and the enlarged drilling blade 30 and the curable fluid ejected from the jet port 40 to the through hole 21 e. The flow of soil and hardenable fluid from the surface side to the back surface side or from the back surface side to the surface side of the spiral wing 20 through the through holes 21 e is made smooth. Also in the rotary penetration pile Ag of this modification, the agitation mixing by the flow of the earth and sand and the hardenable fluid performed through the through hole 21e is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30, Agitation mixing with the hardenable fluid is further facilitated, and it becomes possible to form the rooted body F in which earth and sand and the hardenable fluid are uniformly mixed.

  13 (a) and 13 (b) show a sixth embodiment of the rotary penetration pile of the present invention. In the figure, the same parts as the parts shown in FIG. 4A, FIG. 4B, FIG. 5A, and FIG. 5B are assigned the same reference numerals and detailed explanations thereof will be omitted.

  In the rotary penetration pile Ah of the sixth embodiment, the spiral wing 20 is provided with a pair of substantially circular cutouts 21f as a penetrating portion for communicating the front surface side and the rear surface side, and the enlarged cutting edge The pair of notches 21f can be opened and closed by the support pieces 32 of 30. This point is different from the rotary penetration pile Aa of the second embodiment described above, and the other parts are the same. It is the same as the rotary penetration pile Ae of the fourth embodiment described above in that the notch 21f is configured to be openable and closable by the support piece 32. As shown in FIG. 14A, when moving the tip end portion of the pile main body 10 up and down a plurality of times in the support layer S by rotating the rotary penetration pile Ah forward and reversely, as shown in FIG. The earth and sand excavated by the spiral blade 20 and the enlarged drilling blade 30 and the hardenable fluid ejected from the jet nozzle 40 flow from the front surface side to the rear surface side of the spiral blade 20 or from the rear surface side to the front surface side. The agitation mixing by the flow of the soil and the hardenable fluid performed through the notch 21f is added to the agitation mixing using the spiral blade 20 and the enlarged cutting blade 30, the agitation mixing of the sediment and the hardenable fluid is performed. It becomes possible to form the rooting body F in which soil and soil and a hardenable fluid are uniformly mixed. In the sixth embodiment, unlike the fifth embodiment in which the through hole 21d is similarly provided, the notch 21f can be opened and closed by the support piece 32, and the rotation penetration pile Ah is rotated forward to rotate in the ground. At the time of penetration, as shown in FIG. 13A, the notch 21 f is closed by the support piece 32 of the enlarged cutting blade 30 which is accommodated on the peripheral side of the spiral wing 20. For this reason, during rotational penetration, it is possible to prevent the ground reaction force from leaking through the notch 21f, and to prevent the reduction in rotational propulsive force into the ground due to the provision of the notch 21f. As shown in FIG. 13 (b), when the notch portion 21 f rotates the rotary penetration pile Ah in reverse and pulls it out of the ground, the notch portion 21 f is in the radial direction of the pile main body 10 from the peripheral side of the spiral wing 20. It is opened by the support piece 32 of the projecting enlarged cutting blade 30. In addition, even in the rotary penetration pile Ah of the sixth embodiment, the supporting force can be increased by the enlarged digging blade 30 in the same manner as the rotary penetration pile A of the first embodiment described above, and the mark 70 (see FIG. By observing 1 (a) or the like), it can be detected that the enlarged cutting blade 30 protrudes from the peripheral edge of the spiral wing 20 to the outside in the radial direction of the pile main body 10 in the ground. Further, at the initial stage of rotation in which the pile main body 10 is reversely rotated, the enlarged drilling blade 30 can be reliably protruded to the radially outer side of the pile main body 10.

  The rotary penetration pile of the present invention includes a rotary penetration pile A shown in FIG. 1 (a) etc., a rotary penetration pile Aa shown in FIG. 4 (a) etc., a rotary penetration pile Ab shown in FIG. 7 (a) etc. a) rotational penetrating pile Ac shown in FIG. 9A etc., rotational penetrating pile Ae shown in FIG. 10A etc., rotational penetrating pile Af shown in FIG. 11A, FIG. It is not limited to the rotation penetration pile Ag shown to (a) etc., and the rotation penetration pile Ah etc shown to FIG. 13 (a) etc. FIG.

  Moreover, in the construction method of the rooted foundation using the rotary penetration pile of the present invention, when the rotary penetration pile A shown in FIG. 1 (a), (b), etc. is used (FIGS. ), But the invention is not limited thereto. For example, a rotary penetration pile Aa shown in FIG. 4 (a) etc., a rotary penetration pile Ab shown in FIG. 7 (a) etc., FIG. 8 (a) etc. 9 (a) etc., a rotary penetration pile Ae shown in FIG. 10 (a) etc., a rotary penetration pile Af shown in FIG. 11 (a), FIG. 12 (a) A rotary penetration pile Ag shown in FIG. 13 or a rotary penetration pile Ah shown in FIG. 13A or the like may be used.

  For example, when using the rotary penetration pile Ab shown in FIG. 7 (a) etc., when moving the tip portion of the pile body 10 up and down in the support layer S (between a predetermined position and a predetermined depth) (the rotation During the repetition of the penetration process and the rotational pulling process), the stirring and mixing by the flow of the earth and sand and the hardenable fluid performed through the through hole 21 is the stirring and mixing using the spiral blade 20 and the enlarged cutting blade 30 In addition, stirring and mixing of the soil and the hardenable fluid is further facilitated, and it is possible to form the root compact F in which the soil and the hardenable fluid are uniformly mixed.

  The construction method of a rooted foundation using the rotary penetration pile and the rotary penetration pile according to the present invention is applied to the case of improving the pushing support force and the pull-out support force without increasing the outer diameter of the spiral blade. .

A, Aa Rotary penetration pile Ab, Ac Rotary penetration pile Ad, Ae Rotary penetration pile Af, Ag Rotary penetration pile Ah Rotary penetration pile S Support layer F Rooted body 10 Pile body 11 Outer cylinder 12 Inner cylinder 13 Bottom cover 20 Spiral wing 21 through hole 21a notch portion 21b through hole 21c through hole 21d through hole 21e through hole 21f notch portion 22 guide portion 22a guide portion 30 enlarged excavating blade 40 jet port 60 curable fluid supply pipe 70 mark 80 pin 81 groove portion

Claims (11)

A pile body comprising: an outer cylinder; and an inner cylinder disposed in a tip portion of the outer cylinder in a state where the closed tip is exposed from the outer cylinder;
A helical wing provided along an outer peripheral surface of the inner cylinder near the tip end of the inner cylinder exposed from the outer cylinder;
An enlarged drilling blade provided on the spiral wing so as to be able to project radially outward of the pile body;
And a jet of a hardenable fluid provided at a circumferential surface portion which is openably and closably covered by the outer cylinder of the inner cylinder,
The outer cylinder is movable in the axial direction by a predetermined distance while rotating at a predetermined angle with respect to the inner cylinder when the pile main body is rotated in a direction opposite to the direction in which the pile body is inserted into the ground.
The enlarged cutting blade is housed on the peripheral side of the spiral blade when the pile body is rotationally inserted into the ground, and is rotated in the direction opposite to the direction in which the pile body is rotated. Protruding radially outward of the pile main body from the peripheral edge of the spiral wing by means of the outer cylinder which rotates in the opposite direction,
When the outer cylinder is moved in the axial direction relative to the inner cylinder when the pile main body is rotated in the direction opposite to the direction in which the rotary penetration is made, the enlarged cutting blade is a peripheral edge of the spiral wing The rotary penetration pile characterized by detecting that it protruded to the diameter direction outside of the above-mentioned pile body from the above. In the rotary penetration pile according to claim 1,
Screws having the same pitch as the pitch of the spiral blade are provided on the inner peripheral surface of the tip end portion of the outer cylinder and the outer peripheral surface of the inner cylinder, and the inner cylinder is placed inside the tip portion of the outer cylinder A rotary penetration pile characterized by being screwed into one. In the rotary penetration pile of the foundation pile according to claim 1 or 2,
The jet nozzle is provided between the end portions of the spiral blade on the circumferential surface of the inner cylinder, and when the pile main body is rotationally penetrated into the ground, is covered by the outer cylinder to cause the pile main body to rotationally penetrate. The rotary penetration pile characterized in that when rotating in the direction opposite to the direction, the outer cylinder rotates with respect to the inner cylinder and is not covered by the outer cylinder. In the rotary penetration pile according to claim 2 or 3,
When the outer cylinder is rotated relative to the inner cylinder and moved in the axial direction by a predetermined pitch by rotating the pile main body in the direction opposite to the direction in which the pile is inserted into the ground, the outer cylinder relative to the inner cylinder The rotary penetration pile characterized by having provided the stopper which stops movement. In the rotation penetration pile according to any one of claims 1 to 4,
The rotary digging pile characterized in that the enlarged digging blade is provided so as to be able to pivot with respect to the spiral wing. In the rotary penetration pile according to claim 5,
The enlarged digging blade is pushed and rotated by the outer cylinder rotating with respect to the inner cylinder when rotating the pile main body in the direction opposite to the direction in which the rotary penetration is made, from the peripheral edge of the spiral wing The rotary penetration pile characterized by protruding to the radial direction outer side of the said pile main body. In the rotary penetration pile according to claim 5,
The outer cylinder is provided with a pin parallel to the axial direction of the outer cylinder, and the end of the enlarged cutting blade is provided with a groove portion in which the pin is slidably engaged.
When the enlarged excavation blade rotates the pile main body in the direction opposite to the direction in which the rotary penetration is performed, the pin moves in the groove along with the outer cylinder rotating with respect to the inner cylinder. A rotary penetration pile characterized by rotating and protruding radially outward of the pile main body from the peripheral edge of the spiral wing. In the rotary penetration pile according to claim 5,
The rotary penetration pile characterized by providing the penetration part which makes the one side and the other side communicate on the said spiral wing. In the rotary penetration pile according to claim 8,
The enlarged digging blade includes a support piece slidably provided relative to the spiral blade, and a digging piece provided at an outer end of the support piece and extending in the axial direction of the pile body.
The penetration portion is closed by the support piece when the pile body is rotationally penetrated into the ground, and is opened by the support piece when the pile body is rotated in the direction opposite to the rotation penetration direction. Thus, the rotary penetration pile characterized in that it is configured to be able to open and close using the support piece. It is a construction method of a rooted foundation using a rotating penetration pile,
A pile body comprising: an outer cylinder; and an inner cylinder disposed in a tip portion of the outer cylinder in a state where the closed tip is exposed from the outer cylinder;
A helical wing provided along an outer peripheral surface of the inner cylinder near the tip end of the inner cylinder exposed from the outer cylinder;
An enlarged drilling blade provided on the spiral wing so as to be able to project radially outward of the pile body;
And a jet of a hardenable fluid provided at a circumferential surface portion which is openably and closably covered by the outer cylinder of the inner cylinder,
The outer cylinder moves a predetermined distance in the axial direction while rotating at a predetermined angle with respect to the inner cylinder when rotating the pile main body in the direction opposite to the direction in which the pile body is inserted into the ground.
The enlarged cutting blade is housed on the peripheral side of the spiral blade when the pile body is rotationally inserted into the ground, and is rotated in the direction opposite to the direction in which the pile body is rotated. Protruding radially outward of the pile main body from the peripheral edge of the spiral wing by means of the outer cylinder which rotates in the opposite direction,
The jet nozzle is covered by the outer cylinder when the pile body is rotationally inserted into the ground, and the outer cylinder is rotated relative to the inner cylinder when the pile body is rotated in the direction opposite to the rotational insertion direction. Use a rotating penetration pile,
A step of preparing a hardenable fluid supply pipe on the pile body;
A rotational penetration process in which the pile body is rotated and penetrated into the ground to a predetermined depth by the propulsive force of the spiral blade;
In the initial stage of rotation in which the pile main body is rotated in the direction opposite to the direction in which the rotary penetration is made, the outer cylinder is moved relative to the inner cylinder by a predetermined distance while rotating with respect to the inner cylinder. A confirmation step of confirming that the blade protrudes outward in the radial direction of the pile main body from the peripheral edge of the spiral wing;
After the confirmation step, while the pile main body is rotated in the direction opposite to the direction in which the rotary penetration is made and pulled up from the predetermined depth to the predetermined position, the curable fluid supply pipe is not covered by the outer cylinder And b) a rotary pull-up step of excavating the ground around the spiral blade by the enlarged cutting blade while spouting the hardenable fluid through a spout.
While repeating the rotational penetration process and the rotational pulling process between the predetermined position and the predetermined depth, the earth and sand excavated by the spiral wing and the enlarged digging blade and the hardenability ejected from the jet nozzle are repeated. A method of constructing a rooted foundation using a rotary penetration pile, characterized in that the mixture is stirred and mixed with a fluid. It is a construction method of a rooted foundation using a rotating penetration pile,
A pile body comprising: an outer cylinder; and an inner cylinder disposed in a tip portion of the outer cylinder in a state where the closed tip is exposed from the outer cylinder;
A helical wing provided along an outer peripheral surface of the inner cylinder near the tip end of the inner cylinder exposed from the outer cylinder;
A penetrating portion communicating the one surface side of the spiral wing with the other surface side;
An enlarged drilling blade provided on the spiral wing so as to be able to project radially outward of the pile body;
And a jet of a hardenable fluid provided at a circumferential surface portion which is openably and closably covered by the outer cylinder of the inner cylinder,
The outer cylinder moves a predetermined distance in the axial direction while rotating at a predetermined angle with respect to the inner cylinder when rotating the pile main body in the direction opposite to the direction in which the pile body is inserted into the ground.
The enlarged cutting blade is housed on the peripheral side of the spiral blade when the pile body is rotationally inserted into the ground, and is rotated in the direction opposite to the direction in which the pile body is rotated. Protruding radially outward of the pile main body from the peripheral edge of the spiral wing by means of the outer cylinder which rotates in the opposite direction,
The jet nozzle is covered by the outer cylinder when the pile body is rotationally inserted into the ground, and the outer cylinder is rotated relative to the inner cylinder when the pile body is rotated in the direction opposite to the rotational insertion direction. Use a rotating penetration pile,
A step of preparing a hardenable fluid supply pipe on the pile body;
A rotational penetration process in which the pile body is rotated and penetrated into the ground to a predetermined depth by the propulsive force of the spiral blade;
In the initial stage of rotation in which the pile main body is rotated in the direction opposite to the direction in which the rotary penetration is made, the outer cylinder is moved relative to the inner cylinder by a predetermined distance while rotating with respect to the inner cylinder. A confirmation step of confirming that the blade protrudes outward in the radial direction of the pile main body from the peripheral edge of the spiral wing;
After the confirmation step, while the pile main body is rotated in the direction opposite to the direction in which the rotary penetration is made and pulled up from the predetermined depth to the predetermined position, the curable fluid supply pipe is not covered by the outer cylinder And b) a rotary pull-up step of excavating the ground around the spiral blade by the enlarged cutting blade while spouting the hardenable fluid through a spout.
While repeating the rotational penetration process and the rotational pulling process between the predetermined position and the predetermined depth, the earth and sand excavated by the spiral wing and the enlarged digging blade and the hardenability ejected from the jet nozzle are repeated. The fluid is stirred and mixed, and excavated by the spiral blade and the enlarged cutting blade from the one surface side of the spiral blade to the other surface side or the other surface side from the one surface side through the penetration portion. A method of constructing a rooted foundation using a rotary penetrable pile, characterized in that the deposited soil and the hardenable fluid are made to flow and be stirred and mixed.