JP7598144B2 - Winged steel pipe pile installation device and method for installing a winged steel pipe pile - Google Patents

Description

This disclosure relates to a winged steel pipe pile installation device and a method for installing a winged steel pipe pile.

When constructing a building, pile foundations may be installed in the ground using the rotary press-in method. In rotary press-in methods using steel pipe piles, it is known that an effective method is to attach fins (wings) to the end of the steel pipe pile facing the ground in order to make it easier to press in by rotation during construction and to increase the bearing capacity of the ground after construction. It is also known that the fins and a thin-diameter steel pipe pile are separately inserted into the ground to create a steel pipe pile with wings.

Patent Document 1 describes a method for installing steel pipe piles with wings that improve the bearing capacity of the ground. The casing used in this method is composed of a casing body which is a hollow tube, a first fin fixedly attached to the outer periphery of the ground side end of the casing body, a second fin detachably engaged with the bottom surface of the ground side end of the casing body so as to cover its opening, and at least one hook mechanism for detachably engaging the second fin with the casing body. The publication discloses two examples of the hook mechanism.

The hook mechanism of the first example is composed of a base portion attached to the underside of the surface of the first fin, and a claw portion provided at the tip of the base portion that engages the second fin. When the casing is rotated and pressed into the ground by the rotary pressing method, the claw portion of the hook mechanism automatically engages with the second fin due to the forward rotation, and when the casing is rotated in the reverse direction to be pulled out above ground, the claw portion of the hook mechanism automatically disengages from the second fin.

The hook mechanism of the second example is composed of a first arm supported on a fulcrum inside the casing body so as to be rotatable in the vertical direction, a second arm articulated to the outer end of the first arm and extending to the outside of the casing body, and a claw provided at the tip of the second arm for engaging the second fin. When the casing is rotary-pressed into the ground by the rotary press-in method, and when the casing is rotated in the reverse direction midway through and pulled out for some reason, the second fin engaged by this hook mechanism rotates in the same direction as the casing body. The inner end of the first arm of the hook mechanism is positioned so that the circumferential portion of the steel pipe pile comes into contact with the small diameter steel pipe pile when the steel pipe pile is guided by the protruding portion protruding from the center of the second fin. When the casing reaches a predetermined position in the ground and the steel pipe pile is inserted into the hollow part of the casing body, the circumferential part of the steel pipe pile pushes the inner end of the first arm of the hook mechanism, lifting the second arm and releasing the claw part from the second fin.

JP 2013-151850 A

In the first example of the casing hook mechanism described in Patent Document 1, the base is attached to the underside of the surface of the first fin and extends toward the second fin (fin), so when the casing body (casing) is rotated in the opposite direction to the pressing-in direction, the base may interfere with the blade on the opposite side of the second fin, causing the hook mechanism to interfere with the rotation of the casing. In the second example of the casing hook mechanism described in Patent Document 1, the inner end of the first arm of the hook mechanism is positioned so that the circumferential part of the small diameter steel pipe pile comes into contact with the inner end of the first arm of the hook mechanism in order to detach the casing body (casing) from the second fin (fin). This can result in a complex structure.

Therefore, the present disclosure aims to provide a winged steel pipe pile installation device and a winged steel pipe pile installation method that can detach the casing from the fin with a simple structure without interfering with the rotation of the casing.

In order to solve the above problem, the winged steel pipe pile installation device of the first aspect of the present invention comprises a hollow tubular casing that extends in a predetermined direction and defines a pile insertion space into which a steel pipe pile can be inserted, a hook member that is provided on the outer circumferential surface of one end of the casing on one side in the predetermined direction and is supported on the casing so as to be tiltable about a predetermined hook rotation axis, a central portion that covers one side opening on one side of the casing, a pile connection portion that protrudes from the central portion to the other side in the predetermined direction and is connectable to the steel pipe pile, and a wing-like portion that extends outward from the central portion, and is supported detachably on the casing via the hook member, and the hook member has a normal position in which it extends from the hook rotation axis side toward the radially outward side of the casing and an avoidance position in which the tip side of the hook member is positioned on at least one side of the other side in the predetermined direction and the first rotation direction of the casing from the normal position. When the casing is rotated in the first rotation direction with the center of the fin covering the one side opening of the casing, the hook member in the normal position is in an engaged state in which the wing-like portion of the fin is engaged, and when the casing is rotated in a second rotation direction opposite to the first rotation direction, the hook member in the normal position is in an engaged state in which the wing-like portion of the fin is disengaged. When the casing is rotated in the second rotation direction opposite to the first rotation direction, the hook member in the engaged state rotates in the first rotation direction in conjunction with the rotation of the casing in the first rotation direction, and when the casing is rotated in the released state, the hook member does not rotate even when the casing is rotated in the second rotation direction. When the hook member in the released state comes into contact with the wing-like portion of the fin when the casing is rotated in the second rotation direction, the hook member in the released state is tilted from the normal position to the avoidance position around the hook rotation axis by the force from the fin.

The second aspect of the present invention is the winged steel pipe pile installation device of the first aspect described above, in which the wing-like portion of the fin in the engaged state is inclined with respect to a plane perpendicular to the rotation axis of the casing so that the end on the first rotation direction side is positioned closer to the one side of the specified direction than the end on the second rotation direction side, and the hook rotation axis of the hook member extends from the other side of the specified direction toward the first rotation direction of the one side of the specified direction when viewed from the radial direction of the casing, and is inclined with respect to the rotation axis of the casing.

The third aspect of the present invention is a winged steel pipe pile installation device according to the first or second aspect, in which the hook member has an arm portion that extends radially outward from the casing side in the normal position, and a claw portion that bends from the tip of the arm portion to the one side in the predetermined direction, and the end of the claw portion of the hook member on the one side in the predetermined direction and on the second rotation direction in the normal position is inclined with respect to the edge of the one side in the predetermined direction and the edge of the claw portion on the second rotation direction.

The fourth aspect of the present invention is a winged steel pipe pile installation device according to any one of the first to third aspects, in which the pile connection portion of the fin is formed in a cylindrical shape that allows the insertion of the end of the steel pipe pile on one side in the specified direction, and the inner circumferential surface of the casing has a large diameter region extending from the one side opening to the other side in the specified direction, and a small diameter region formed with a smaller diameter than the large diameter region and extending from the large diameter region to the other side in the specified direction, the large diameter region on the inner circumferential surface of the casing defines a space that allows the insertion of the pile connection portion of the fin, and the diameter of the small diameter region on the inner circumferential surface of the casing is formed to be equal to or smaller than the inner diameter of the pile connection portion.

The fifth aspect of the present invention is a winged steel pipe pile installation device according to any one of the first to fourth aspects, comprising a rotation confirmation member that is inserted into the pile insertion space from the other side in the predetermined direction of the casing and is removably supported on the other end of the steel pipe pile in the predetermined direction when inserted into the pile insertion space, and the other end of the rotation confirmation member in the predetermined direction is exposed from the pile insertion space of the casing to the other side in the predetermined direction when the rotation confirmation member is supported on the steel pipe pile, and the rotation confirmation member supported on the steel pipe pile rotates when the steel pipe pile rotates and does not rotate when the steel pipe pile does not rotate.

The sixth aspect of the present invention is a method for installing a winged steel pipe pile using the winged steel pipe pile installation device of any one of the first to fourth aspects, and includes a rotary pressing process for rotating the casing and the fin in the locked state in the first rotation direction to rotary press the pile into the ground, a connection process for stopping the rotation after the fin reaches a desired position, inserting the steel pipe pile from the other side of the casing into the pile insertion space, and connecting the steel pipe pile to the pile connection part of the fin, and an extraction process for rotating the casing in the second rotation direction while leaving the fin and the steel pipe pile in place, and extracting the pile from the ground.

The seventh aspect of the present invention is a method for installing a winged steel pipe pile using the winged steel pipe pile installation device of the fifth aspect, and includes a rotary pressing step in which the casing and the fin in the locked state are rotated in the first rotation direction to rotary press the pile into the ground; a connection step in which, after the fin reaches a desired position, the rotation is stopped, and the steel pipe pile is inserted into the pile insertion space from the other side of the casing and connected to the pile connection part of the fin; a confirmation step in which the rotation confirmation member is inserted into the pile insertion space from the other side of the casing and attached to the steel pipe pile, and then the casing is rotated in the second rotation direction to confirm that the fin will not rotate even if the casing is rotated; and a withdrawal step in which the casing is rotated in the second rotation direction while leaving the fin and the steel pipe pile in place, and withdrawn from the ground.

According to the present disclosure, the casing can be detached from the fin with a simple structure without interfering with the rotation of the casing.

1 is an external view of a winged steel pipe pile installation device according to an embodiment of the present invention. FIG. 4A to 4C are diagrams showing the process of manufacturing a fin, in which (a) shows the state after making a cut, (b) shows the state before bending, and (c) shows the state after bending. FIG. 4 is an external view of a casing and a hook member. FIG. 4 is an external view of FIG. 3 as viewed from a direction IV. 13 is a perspective view of the hook member and the fin in an engaged state, seen from below. FIG. 5A is an explanatory diagram of a hook member showing a state where it is separated from the wing-like portion of the fin, FIG. 5B is a state where it is abutted against the upper surface of the wing-like portion, and FIG. 5C is a state where it is tilted. FIG. 2 is a perspective view from above showing the connection portion between the casing, the fin, and the steel pipe pile. FIG. 13 is an external view of the casing with the confirmation rod inserted therein. FIG. 1 is an explanatory diagram of a method for installing a winged steel pipe pile according to one embodiment of the present invention, in which (a) shows the state in which the fin has been rotated and pressed into the desired position, and (b) shows the state in which the casing is being pulled out.

One embodiment of the present invention will be described below with reference to the drawings. In each drawing, UP indicates the upward direction. In each drawing, CL1 indicates the rotation axis (shaft center) of the casing 20, and CL2 indicates the hook rotation axis (shaft center) of the hook member 30. In addition, the specified direction will be described as the up-down direction, with one side of the specified direction being the lower side and the other side of the specified direction being the upper side.

1 is an external view of a winged steel pipe pile installation device 1 according to one embodiment of the present invention. FIG. 2 is a diagram showing the manufacturing process of the fin 10, where (a) shows the state after the incision is made, (b) shows the state before bending, and (c) shows the state after bending. FIG. 3 is an external view of the casing 20 and the hook member 30. FIG. 4 is an external view of FIG. 3 as viewed from the IV direction. FIG. 5 is a perspective view from below of the hook member 30 and the fin 10 in the engaged state. FIG. 6 is an explanatory diagram of the hook member 30, where (a) shows the state separated from the wing-like portion 12 of the fin 10, (b) shows the state abutting against the upper surface 14 of the wing-like portion 12, and (c) shows the state tilted. FIG. 7 is an oblique view from above showing the connection portion of the casing 20, the fin 10, and the steel pipe pile 50. FIG. 8 is an external view of the casing 20 with the confirmation rod 40 inserted. Figure 9 is an explanatory diagram of a method for installing a winged steel pipe pile according to one embodiment of the present invention, where (a) shows the state in which the fin 10 has been rotated and pressed into the desired position, and (b) shows the state in which the casing 20 has been pulled out. Note that the hook member 30 is not shown in Figure 7.

As shown in FIG. 1, the winged steel pipe pile installation device 1 according to this embodiment is a device for installing winged steel pipe piles in the ground, which serve as pile foundations when constructing a building. When installing a winged steel pipe pile in the ground, first, the fins 10 (wings) are installed in the ground, and then the steel pipe pile 50 is connected to the fins 10 installed in the ground (see FIG. 9(b)). In other words, the winged steel pipe pile is composed of the fins 10 and the steel pipe pile 50 connected to the fins 10.

The steel pipe pile 50 has the smallest possible diameter within a range that can obtain a predetermined bearing capacity after construction, and has a connection portion 50a at the lower end (see Figures 7 and 9 (b)). The connection portion 50a is provided with a protrusion 51 that protrudes from the outer circumferential surface of the connection portion 50a. The protrusion 51 is supported by the steel pipe pile 50 in a state in which it is biased from the radial inside to the radial outside of the steel pipe pile 50. The protrusion 51 is pressed from the radial outside and retracts radially inward against the biasing force, and when the input of force from the radial outside is no longer applied, it is biased from the radial inside and protrudes radially outward. The steel pipe pile 50 is not particularly limited as long as it has an outer diameter R2 that can be inserted into the casing 20 and can maintain its strength after construction, but for example, a single pipe can be used as a suitable example.

The winged steel pipe pile installation device 1 according to this embodiment includes a fin 10 for burying in the ground, a hollow tubular casing 20 extending in the vertical direction, a hook member 30 for engaging the fin 10, and a confirmation rod (rotation confirmation member) 40 for confirming the rotation of the fin 10. In the following description, the first rotation direction is the direction in which the casing 20 is rotated during excavation (in this embodiment, the clockwise direction when viewed from above), and the second rotation direction is the direction opposite to the first rotation direction (in this embodiment, the direction opposite to the clockwise direction when viewed from above).

As shown in Figures 1 and 2, the fin 10 has a generally square central portion 11 that abuts against the bottom surface of the lower end portion (one end portion) 20a of the casing 20 and covers the lower end opening (one side opening) 20b (see Figure 7) of the casing 20, four wing-like portions 12 extending outward from each of the four sides of the central portion 11, and a cylindrical pile connection portion 13 that is integrally provided approximately in the center of the central portion 11. The central portion 11 and the four wing-like portions 12 of the fin 10 are formed from a single plate-like member 16 as described below (see Figure 2 (a)).

The central portion 11 of the fin 10 is formed in a plate shape that intersects with a predetermined direction (the up-down direction in this embodiment). As described below, when the fin 10 is attached to the casing 20 and locked, the central portion 11 intersects with the rotation axis CL1 of the casing 20 (see FIG. 1).

The cylindrical pile connection portion 13 of the fin 10 is positioned approximately in the center of the upper surface of the central portion 11 and protrudes upward. The pile connection portion 13 defines a space 15 that is open upward. The space 15 of the pile connection portion 13 is formed to a size that allows the insertion of the connection portion 50a of the steel pipe pile 50. The pile connection portion 13 is provided with an opening 13a that radially connects the inner space 15 to the outside. The opening 13a of the pile connection portion 13 is formed to a size that allows the protrusion portion 51 (see Figure 7) of the steel pipe pile 50 to be engaged. When the connection portion 50a of the steel pipe pile 50 is inserted into the space 15 of the pile connection portion 13, the protrusion 51 of the steel pipe pile 50 is pressed radially inward and retracted by contacting the pile connection portion 13, and when it reaches the position of the opening 13a of the pile connection portion 13, it is biased from the radially inner side and protrudes radially outward, and is engaged with the opening 13a of the pile connection portion 13. This connects the steel pipe pile 50 and the fin 10. When the steel pipe pile 50 and the fin 10 are connected, the relative rotation of the steel pipe pile 50 and the fin 10 is restricted by the engagement between the protrusion 51 of the steel pipe pile 50 and the opening 13a of the pile connection portion 13.

The four wing-like portions 12 of the fin 10 are formed by alternately bending upward and downward with respect to the central portion 11. Specifically, the first wing-like portion 12a is bent upward with respect to the central portion 11, the second wing-like portion 12b adjacent to the first wing-like portion 12a is bent downward with respect to the central portion 11, the third wing-like portion 12c located diagonally from the second wing-like portion 12b is bent downward with respect to the central portion 11, and the fourth wing-like portion 12d adjacent to the third wing-like portion 12c is bent upward with respect to the central portion 11 (see Figs. 2(b) and 2(c)). In other words, the diagonally positioned wing-like portions 12 are bent in the same direction, that is, the first and fourth wing-like portions 12a and 12d are both bent upward with respect to the central portion 11, and the second and third wing-like portions 12b and 12c are both bent downward with respect to the central portion 11. Each wing-like portion 12 is inclined with respect to the central portion 11 so that the end portion on the first rotation direction (the direction shown by the white arrow in FIG. 2(c)) side is located lower than the end portion on the second rotation direction (the opposite direction to the white arrow in FIG. 2(c)). That is, each wing-like portion 12 is inclined with respect to a plane perpendicular to the rotation axis CL1 of the casing 20 so that the end portion on the first rotation direction side is located lower than the end portion on the second rotation direction side when the fin 10 is attached to the casing 20 in a locked state as described later. The shape of the fin 10 is not limited to the shape described here, and for example, the central portion 11 does not have to be square, and may be any shape as long as it can cover the lower end opening 20b of the casing 20. The wing-like portion 12 does not have to be a shape obtained by bending a rectangle obliquely, and may be a fan shape or a ring shape, and the number of wing-like portions may be appropriately determined. The material from which the fins 10 are made may be metal (e.g., steel) or polyvinyl chloride, and an appropriate material may be selected taking into account the material of the casing 20.

As shown in Figures 3 to 7, the casing 20 is a hollow tubular (cylindrical in this embodiment) member, and defines a pile insertion space 21 into which a steel pipe pile 50 can be inserted. A plurality of cutting blades 22 are spirally provided on the outer peripheral surface 61 of the casing 20. As shown in Figure 7, the inner peripheral surface 23 of the casing 20 has a large diameter region 23a that extends upward continuously from the lower end opening 20b, and a small diameter region 23b that extends upward from the large diameter region 23a. The inner diameter r1 of the large diameter region 23a of the inner peripheral surface 23 of the casing 20 is slightly larger than the outer diameter R1 of the pile connection portion 13 of the fin 10. In other words, the large diameter region 23a of the inner peripheral surface 23 of the casing 20 defines a space 24 that allows the pile connection portion 13 of the fin 10 to be inserted. The vertical length L1 of the large diameter region 23a of the inner peripheral surface 23 of the casing 20 is set to be equal to or larger than the vertical length L2 of the pile connection portion 13 (slightly longer than the vertical length L2 of the pile connection portion 13 in this embodiment). The small diameter region 23b of the inner peripheral surface 23 of the casing 20 is formed to be smaller than the large diameter region 23a. The inner diameter (diameter) r2 of the small diameter region 23b of the inner peripheral surface 23 of the casing 20 is formed to be equal to or smaller than the inner diameter r3 of the pile connection portion 13 of the fin 10 (in this embodiment, the same size as the inner diameter r3 of the pile connection portion 13). The inner diameter r2 of the small diameter region 23b of the inner peripheral surface 23 of the casing 20 and the inner diameter r3 of the pile connection portion 13 are larger than the outer diameter R2 of the steel pipe pile 50. In this embodiment, a plurality of cutting blades 22 are provided on the outer peripheral surface 61 of the casing 20, but this is not limited thereto. For example, a spiral cutting blade 22 that is continuous from top to bottom may be provided. Alternatively, the cutting blade 22 may not be provided on the outer peripheral surface 61 of the casing 20. In this embodiment, the casing 20 has a cylindrical shape, but as long as it has a hollow cylindrical shape, the outer shape of the cross section of the casing 20 is not limited to a circle. For example, the outer shape of the cross section of the casing 20 may be a square. The material forming the casing 20 may be made of metal (for example, steel) or polyvinyl chloride. The strength of the polyvinyl chloride casing 20 is slightly lower than that of a casing 20 made of a steel pipe, for example, but it is sufficient to select a material that is suitable for the ground conditions at the construction site.

As shown in Figures 3 to 5, a hook support portion 25 is fixedly provided at the lower end portion 20a of the casing 20. In this embodiment, two hook support portions 25 are provided. The two hook support portions 25 are provided on both sides of the casing 20 in a direction intersecting with the rotation axis CL1, and protrude radially outward from the outer peripheral surface 61 of the casing 20. The hook support portion 25 has an upper plate portion 25a, a lower plate portion 25b, and a connecting plate portion 25c. The upper plate portion 25a and the lower plate portion 25b are plate portions that intersect with the up-down direction and are arranged spaced apart from each other vertically. The upper plate portion 25a and the lower plate portion 25b are inclined with respect to a plane perpendicular to the rotation axis CL1 of the casing 20 so that the end portion on the first rotation direction side is located higher than the end portion on the second rotation direction side. The connecting plate portion 25c is a plate portion that connects the ends of the upper plate portion 25a and the lower plate portion 25b on the second rotation direction side. The upper plate portion 25a, the lower plate portion 25b, and the connecting plate portion 25c define a space 29 into which the hook member 30 can be inserted. The space 29 of the hook support portion 25 is opened to the radial outside of the casing 20 and to the first rotation direction side. As shown in Fig. 5, in this embodiment, a portion where the lower end edge of the connecting plate portion 25c and the end edge of the lower plate portion 25b on the second rotation direction side intersect is chamfered to form an inclined surface 28 that is inclined with respect to the surface 26 on the second rotation direction side of the connecting plate portion 25c and the lower surface 27 of the lower plate portion 25b. The hook support 25 is positioned at a height where it does not come into contact with (does not interfere with) the wing-like portion 12 of the fin 10 (the first and fourth wing-like portions 12a and 12d in this embodiment) even when the casing 20 is rotated with the bottom surface of the lower end portion 20a of the casing 20 in contact with the upper surface of the center portion 11 of the fin 10.

3 to 6, the hook member 30 is a member that detachably engages the casing 20 and the fin 10, and is supported on the casing 20 (hook support portion 25 in this embodiment) so as to be tiltable around the hook rotation axis CL2. In this embodiment, two hook members 30 are provided. The hook member 30 is tiltable around the hook rotation axis CL2 between a normal position (the position of the hook member 30 shown in Figures 6(a) and 6(b)) extending radially outward from the hook rotation axis CL2 side of the casing 20, and an avoidance position (the position of the hook member 30 shown in Figure 6(c)) in which the tip side of the hook member 30 is positioned above the normal position and at least in one direction of the first rotation direction (in this embodiment, above and in the first rotation direction). The hook rotation axis CL2 of the hook member 30 is a rotation axis that is perpendicular to the upper plate portion 25a and the lower plate portion 25b of the hook support portion 25, and when viewed from the radial direction of the casing 20, it extends from the upper side toward the lower side in the first rotation direction and is inclined with respect to the rotation axis CL1 of the casing 20 (see Figures 4 and 5). In the following description, the directions related to the hook member 30 indicate the directions in the normal position unless otherwise specified. In addition, the radial direction in the description of the hook member 30 indicates the radial direction of the casing 20.

The hook member 30 integrally has an arm portion 31 extending radially outward from the hook rotation axis CL2 side of the casing 20, and a claw portion 32 that is bent downward and folded back from the tip of the arm portion 31. The arm portion 31 is formed in a plate shape that intersects with the up-down direction of the plate thickness that can be inserted into the space 29 of the hook support portion 25, and is inserted into the space 29 of the hook support portion 25. The arm portion 31 is supported by the upper plate portion 25a and the lower plate portion 25b of the hook support portion 25 so that it can tilt around the hook rotation axis CL2. The claw portion 32 is folded back downward from the radially outer edge of the arm portion 31. As shown in FIG. 5, the portion where the lower end edge (edge on one side in a predetermined direction) 34 of the claw portion 32 intersects with the edge 35 in the second rotation direction is chamfered to form an inclined surface 33 (curved surface in this embodiment) inclined with respect to the lower end edge 34 of the claw portion 32 and the edge 35 in the second rotation direction of the claw portion 32. That is, the lower end (inclined surface 33) of the claw portion 32 in the second rotation direction is inclined with respect to the lower end edge 34 of the claw portion 32 and the edge 35 in the second rotation direction of the claw portion 32. In the normal position of the hook member 30, the arm portion 31 extends radially outward from the hook rotation axis CL2 side, and in the avoidance position of the hook member 30, the arm portion 31 extends upward in the first rotation direction from the hook rotation axis CL2 side. The hook member 30 can be tilted along the lower surface of the upper plate portion 25a and the upper surface of the lower plate portion 25b of the hook support portion 25 around the hook rotation axis CL2. That is, the tip side (claw portion 32 side) of the hook member 30 can be tilted from the normal position to an upper avoidance position in the first rotation direction, centered on the hook rotation axis CL2. The upper plate portion 25a and the lower plate portion 25b of the hook support portion 25 are inclined so that the end portion on the second rotation direction side is located lower than the end portion on the first rotation direction side, so that the arm portion 31 of the hook member 30 is positioned in the normal position by its own weight when not subjected to an external force.

When the fin 10 is engaged with the casing 20 side by the hook member 30, the casing 20 is rotated in the first rotation direction with the pile connection portion 13 of the fin 10 inserted from the lower end opening 20b of the casing 20 into the space 24 defined by the large diameter region 23a of the inner circumferential surface 23. When the pile connection portion 13 of the fin 10 is inserted from the lower end opening 20b of the casing 20 into the space 24 defined by the large diameter region 23a of the inner circumferential surface 23, the lower end opening 20b of the casing 20 is covered by the center portion 11 of the fin 10. In other words, when the fin 10 is engaged with the casing 20 side by the hook member 30, the casing 20 is rotated in the first rotation direction with the center portion 11 of the fin 10 covering the lower end opening 20b of the casing 20. When the casing 20 is rotated in the first rotation direction, the claw portion 32 of the hook member 30 in the normal position automatically engages the wing portion 12 of the fin 10 to enter the engaged state (see Figs. 1 and 5). In this embodiment, the claw portion 32 of the hook member 30 in the engaged state engages the first and fourth wing portions 12a and 12d located above the central portion 11. In the engaged state, the bottom surface of the lower end portion 20a of the casing 20 abuts against the upper surface of the central portion 11 of the fin 10, and the lower end opening 20b of the casing 20 is covered by the central portion 11 of the fin 10. When the casing 20 is rotated in the first rotation direction, the fin 10 in the engaged state rotates in the first rotation direction in conjunction with the rotation of the casing 20. To release the engagement of the fin 10 by the hook member 30, the casing 20 is rotated in the second rotation direction from the engaged state. When the casing 20 is rotated in the second rotation direction from the locked state, the claw portion 32 of the hook member 30 in the normal position automatically disengages from the wing-like portion 12 of the fin 10, and the fin 10 is released from the locked state on the casing 20 side (see FIG. 6(a)). That is, the fin 10 is detachably supported on the casing 20 via the hook member 30. When the casing 20 is further rotated in the second rotation direction and the hook member 30 in the unlocked state in the normal position abuts against the upper surface 14 of the wing-like portion 12 of the fin 10 (see FIG. 6(b)), the tip side (claw portion 32 side) of the hook member 30 is tilted from the normal position to the upper avoidance position in the first rotation direction around the hook rotation axis CL2 by the force from the wing-like portion 12 of the fin 10 (see FIG. 6(c)). That is, in the unlocked state, the fin 10 does not rotate even if the casing 20 is rotated in the second rotation direction. In this embodiment, two hook members 30 are provided, but this is not limited to this, and one or three or more hook members 30 may be provided, taking into consideration the ground conditions, the shape of the fin 10, etc.

As shown in FIG. 8, the confirmation rod 40 is a rod-shaped member for confirming the rotation of the fin 10, and is inserted into the pile insertion space 21 (see FIG. 7) from the upper end opening 20c (the opening 20c on the other side in a predetermined direction) of the casing 20. The lower end 40a of the confirmation rod 40 inserted into the pile insertion space 21 of the casing 20 is removably connected to the upper end 52 of the steel pipe pile 50 in the pile insertion space 21. The connection between the confirmation rod 40 and the steel pipe pile 50 means a state in which the confirmation rod 40 is rotatably connected to the steel pipe pile 50 when the steel pipe pile 50 rotates. For example, the lower end surface of the confirmation rod 40 may be placed on the upper end surface of the steel pipe pile 50, and when the steel pipe pile 50 rotates, the confirmation rod 40 may rotate by friction. When the confirmation rod 40 and the steel pipe pile 50 are connected, the confirmation rod 40 is supported from below by the steel pipe pile 50. In this embodiment, the lower end 40a of the confirmation rod 40 is formed thin so that it can be inserted into the inner diameter part of the upper end 52 of the steel pipe pile 50. By pulling the confirmation rod 40 upward from the casing 20, the lower end 40a of the confirmation rod 40 can be removed from the upper end 52 of the steel pipe pile 50. When the confirmation rod 40 is inserted into the pile insertion space 21 from the upper end opening 20c of the casing 20 and the lower end 40a of the confirmation rod 40 is inserted into the inner diameter part of the upper end 52 of the steel pipe pile 50 and attached, the confirmation rod 40 is supported by the steel pipe pile 50 from below. The length L3 from the upper end of the steel pipe pile 50 to the upper end of the confirmation rod 40 in the state where the steel pipe pile 50 is inserted into the pile insertion space 21 of the casing 20 and connected to the fin 10 is set to be longer than the length L4 from the upper end of the steel pipe pile 50 to the upper end opening 20c of the casing 20. That is, the upper end of the confirmation rod 40 is exposed upward from the pile insertion space 21 of the casing 20 with the lower end 40a of the confirmation rod 40 supported by the upper end 52 of the steel pipe pile 50. A head 41 that protrudes in a direction intersecting the axial direction is provided at the upper end of the confirmation rod 40. The length of the head 41 in the direction intersecting the axial direction is set so that it protrudes radially outward from the outer shape of the casing 20 when the confirmation rod 40 is inserted into the pile insertion space 21 of the casing 20. The confirmation rod 40 supported by the steel pipe pile 50 rotates when the steel pipe pile 50 rotates with the rotation of the fin 10, and does not rotate when the fin 10 and the steel pipe pile 50 do not rotate.

Next, a method for installing a winged steel pipe pile according to one embodiment of the present invention will be described with reference to Figures 7 to 9. The method for installing a winged steel pipe pile is a construction method for installing a winged steel pipe pile (fin 10 and steel pipe pile 50) that serves as a pile foundation in the ground using a winged steel pipe pile installation device 1 in order to improve the ground. Note that the hook member 30 is not shown in Figure 7. Also, the multiple cutting blades 22 of the casing 20 are not shown in Figure 9.

First, the upper end of the casing 20 is connected to a rotary press-in device (not shown) mounted on heavy equipment (not shown). That is, the casing 20 is driven to rotate by the rotary press-in device of the heavy equipment. Then, with the pile connection portion 13 of the fin 10 inserted from the lower end opening 20b of the casing 20 into the space 24 defined by the large diameter region 23a of the inner circumferential surface 23, the casing 20 is rotated in the first rotation direction to bring the fin 10 into an engaged state in which it is engaged with the casing 20 side by the hook member 30. In the engaged state, the bottom surface of the lower end portion 20a of the casing 20 abuts against the upper surface of the central portion 11 of the fin 10, and the lower end opening 20b of the casing 20 is covered by the central portion 11 of the fin 10. This is the preparation step.

Based on the above configuration and preparatory actions, the winged steel pipe pile is installed using the winged steel pipe pile installation device 1 according to the following method.

The installation method for the winged steel pipe pile according to this embodiment includes a rotary pressing process, a connection process, a confirmation process, and a pull-out process.

First, as shown in FIG. 9(a), the casing 20 and fins 10 in the locked state are rotated in the first rotational direction to be rotary-pressurized into the ground (rotary pressurization process).

Next, after the fin 10 reaches the desired position, the rotation of the casing 20 is stopped, and the steel pipe pile 50 is inserted into the pile insertion space 21 from the upper end opening 20c on the upper side of the casing 20, and the connection part 50a of the steel pipe pile 50 is connected to the pile connection part 13 of the fin 10 (connection process). In this embodiment, with the steel pipe pile 50 connected to the pile connection part 13 of the fin 10, the relative rotation between the steel pipe pile 50 and the fin 10 is restricted by the engagement between the protrusion part 51 of the steel pipe pile 50 and the opening 13a of the pile connection part 13.

8, the confirmation rod 40 is inserted into the pile insertion space 21 from the upper end opening 20c on the upper side of the casing 20, and the lower end 40a of the confirmation rod 40 is attached to the upper end 52 of the steel pipe pile 50. Then, the casing 20 is rotated in the second rotation direction to confirm that the fin 10 does not rotate even when the casing 20 is rotated (confirmation process). The worker can confirm that the confirmation rod 40 does not rotate by visually checking the upper end (e.g., head 41) of the confirmation rod 40. This allows the worker to confirm that the casing 20 and the fin 10 are detached. At this time, when the casing 20 is rotated in the second rotation direction, the claw portion 32 of the hook member 30 in the normal position automatically detaches from the wing portion 12 of the fin 10, and the engagement of the fin 10 to the casing 20 side is released and the release state is reached (see FIG. 6(a)). When the casing 20 is further rotated in the second rotation direction, and the hook member 30 in the released state in the normal position abuts against the upper surface 14 of the wing-like portion 12 of the fin 10 (see FIG. 6(b)), the tip side (claw portion 32 side) of the hook member 30 tilts from the normal position to the avoidance position on the upper side in the first rotation direction around the hook rotation axis CL2 due to the force from the wing-like portion 12 of the fin 10 (see FIG. 6(c)). In other words, the avoidance position is a position that avoids the rotation trajectory of the wing-like portion 12 of the fin 10. The confirmation rod 40 may be pulled out of the casing 20 after it is confirmed that the fin 10 is not rotating, or it may be automatically removed in the pulling process as described below.

Next, as shown in FIG. 9(b), the casing 20 is rotated in the second rotation direction and pulled out from the ground (pulling-out process) while leaving the fins 10 and the steel pipe piles 50 (steel pipe piles 50 connected to the fins 10) in the ground. During this pulling-out process, soil is backfilled into the excavation hole formed in the rotary pressing process while rotating the casing 20 in the second rotation direction. When the casing 20 is rotated in the second rotation direction and moved upward, the upper end of the casing 20 is caught on the head 41 of the confirmation rod 40, so that the confirmation rod 40 is automatically removed in the pulling-out process. The pulled-out casing 20 can be reused.

As a result, the fin 10 left in the ground and the small diameter steel pipe pile 50 connected to it act as a steel pipe pile with wings.

In the winged steel pipe pile installation device 1 and winged steel pipe pile installation method configured as described above, when the casing 20 is rotated in a first rotation direction with the pile connection portion 13 of the fin 10 inserted into the lower end opening 20b of the casing 20, the hook member 30 provided on the outer peripheral surface 61 of the lower end 20a of the casing 20 engages the wing-like portion 12 of the fin 10, and when the casing 20 is rotated in a second rotation direction, the hook member 30 engages the fin 10, and releases the engagement of the fin 10. In this way, the casing 20 can be detached from the fin 10 with a simple structure in which the hook member 30 is provided on the outer peripheral surface 61 of the lower end 20a of the casing 20 and the casing 20 is rotated in the second rotation direction.

When the casing 20 is rotated in the second rotation direction, the hook member 30 in the released state in the normal position abuts against the upper surface 14 of the wing-like portion 12 of the fin 10, and the tip side of the hook member 30 tilts around the hook rotation axis CL2 due to the force from the wing-like portion 12 of the fin 10 to an avoidance position located above the normal position and at least one side of the first rotation direction (upward and in the first rotation direction in this embodiment). In this way, even if the hook member 30 in the released state abuts against the upper surface 14 of the wing-like portion 12 of the fin 10 when the casing 20 is rotated in the second rotation direction, the hook member 30 in the normal position tilts in a direction that deflects the force from the fin 10 (upward and at least one side of the first rotation direction), so the hook member 30 does not interfere with the rotation of the casing 20.

In addition, the wing-like portion 12 of the fin 10 is inclined with respect to a plane perpendicular to the rotation axis CL1 of the casing 20 so that the end on the first rotation direction side is located lower than the end on the second rotation direction side in the locked state, so that the wing-like portion 12 of the fin 10 can excavate in the rotary press-in process. In addition, the hook rotation axis CL2 of the hook member 30 extends from the upper side toward the lower side in the first rotation direction when viewed from the radial direction of the casing 20, and is inclined with respect to the rotation axis CL1 of the casing 20, so that when the hook member 30 in the released state abuts against the upper surface 14 of the wing-like portion 12 of the fin 10, the hook member 30 can be tilted in a direction to deflect the force from the fin 10.

In addition, an inclined surface 33 is provided on the lower end of the claw portion 32 of the hook member 30 in the second rotation direction. The inclined surface 33 of the claw portion 32 is inclined with respect to the lower edge 34 of the claw portion 32 and the edge 35 of the claw portion 32 in the second rotation direction. Therefore, when the hook member 30 in the released state abuts against the upper surface 14 of the wing-like portion 12 of the fin 10, since the lower end of the claw portion 32 in the second rotation direction is the inclined surface 33, it is possible to prevent the claw portion 32 from getting caught on the upper surface 14 of the wing-like portion 12, and the hook member 30 can be tilted smoothly.

In addition, the hook support portion 25 is positioned at a height position where it does not come into contact with the wing-like portion 12 of the fin 10, even when the casing 20 is rotated with the bottom surface of the lower end portion 20a of the casing 20 in contact with the upper surface of the central portion 11 of the fin 10. Therefore, the hook support portion 25 does not interfere with the wing-like portion 12 of the fin 10 when the casing 20 is rotated in the second rotation direction, and therefore does not impede the rotation of the casing 20.

Therefore, according to this embodiment, the casing 20 can be detached from the fin 10 with a simple structure without interfering with the rotation of the casing 20.

In addition, the portion where the lower end edge of the connecting plate portion 25c of the hook support portion 25 and the edge of the lower plate portion 25b on the second rotation direction side intersect is chamfered, and forms an inclined surface 28 that is inclined with respect to the surface 26 on the second rotation direction side of the connecting plate portion 25c and the lower surface 27 of the lower plate portion 25b. Therefore, even if the wing-shaped portion 12 of the fin 10 is deformed (for example, deformed upward due to the force from the soil below) and the hook support portion 25 abuts against the wing-shaped portion 12 of the fin 10 when the casing 20 is rotated in the second rotation direction, the portion where the lower end edge of the connecting plate portion 25c of the hook support portion 25 and the edge of the lower plate portion 25b on the second rotation direction side intersect is an inclined surface 28, so that it is possible to prevent the hook support portion 25 from getting caught on the upper surface 14 of the wing-shaped portion 12.

The inner circumferential surface 23 of the casing 20 has a large diameter region 23a that extends upward from the lower end opening 20b, and a small diameter region 23b that extends upward from the large diameter region 23a. The large diameter region 23a of the inner circumferential surface 23 of the casing 20 defines a space 24 that allows the insertion of the pile connection portion 13 of the fin 10, and the inner diameter (diameter) r2 of the small diameter region 23b of the inner circumferential surface 23 of the casing 20 is formed to be equal to or smaller than the inner diameter r3 of the pile connection portion 13 of the fin 10. Therefore, after the fin 10 reaches the desired position, the rotation of the casing 20 is stopped, and the steel pipe pile 50 is inserted into the pile insertion space 21 from the upper end opening 20c on the upper side of the casing 20, and the connection portion 50a of the steel pipe pile 50 is easily inserted into the pile connection portion 13 of the fin 10 in the connection process.

In addition, the lower end 40a of the confirmation rod 40 inserted into the pile insertion space 21 of the casing 20 is connected to the upper end 52 of the steel pipe pile 50 in the pile insertion space 21, so that the confirmation rod 40 rotates when the steel pipe pile 50 rotates and does not rotate when the steel pipe pile 50 does not rotate. Therefore, by inserting the confirmation rod 40 into the pile insertion space 21 from the upper end opening 20c on the upper side of the casing 20 and connecting the lower end 40a of the confirmation rod 40 to the upper end 52 of the steel pipe pile 50, it is possible to confirm that the fin 10 does not rotate even when the casing 20 is rotated in the second rotation direction. Therefore, in the extraction process, when the casing 20 is rotated in the second rotation direction and extracted from the ground, the fin 10 and the steel pipe pile 50 can be reliably left in the ground.

In this embodiment, the lower end 40a of the confirmation rod 40 for checking the rotation of the fin 10 is formed thin so that it can be inserted into the inner diameter of the upper end 52 of the steel pipe pile 50, but this is not limited to this, and the shape of the lower end 40a of the confirmation rod 40 can be various shapes that can be connected to the upper end 52 of the steel pipe pile 50.

In addition, in this embodiment, the upper end of the confirmation rod 40 is provided with a head 41 that protrudes in a direction intersecting the axial direction, but this is not limited to this, and the upper end of the confirmation rod 40 can be configured to make it easy to visually check the rotation of the confirmation rod 40 (for example, a pattern written on the surface of the confirmation rod 40).

In addition, in this embodiment, a confirmation rod 40 is provided as a rotation confirmation member to confirm that the fin 10 does not rotate when the casing 20 is rotated in the second rotation direction, but the confirmation rod 40 does not have to be provided. In addition, the installation method for the winged steel pipe pile according to this embodiment includes a confirmation process, but if the confirmation rod 40 is not provided, the confirmation process does not have to be included.

In addition, in this embodiment, a protrusion 51 is provided on the connection portion 50a of the steel pipe pile 50, and an opening 13a in which the protrusion 51 can be engaged is provided on the pile connection portion 13 of the fin 10, and the connection portion 50a of the steel pipe pile 50 and the pile connection portion 13 of the fin 10 are connected in a state in which the relative rotation between the steel pipe pile 50 and the fin 10 is restricted, but this is not limited to this. Various configurations can be applied to the connection mode between the connection portion 50a of the steel pipe pile 50 and the pile connection portion 13 of the fin 10.

In addition, in this embodiment, in order to facilitate the insertion of the steel pipe pile 50 into the pile connection portion 13 of the fin 10, a large diameter region 23a and a small diameter region 23b are provided on the inner peripheral surface 23 of the casing 20, and the inner diameter (diameter) r2 of the small diameter region 23b is formed to be equal to or smaller than the inner diameter r3 of the pile connection portion 13 of the fin 10, but this is not limited to this. For example, the inner diameter r3 of the pile connection portion 13 of the fin 10 may be made larger than the outer diameter of the casing 20, and the lower end portion 20a of the casing 20 may be inserted into the pile connection portion 13 of the fin 10.

In addition, in this embodiment, an inclined surface 33 is provided at the lower end of the claw portion 32 of the hook member 30 in the second rotation direction, and is inclined relative to the lower edge 34 of the claw portion 32 and the edge 35 of the claw portion 32 in the second rotation direction. However, for example, if there is no concern about the claw portion 32 getting caught on the upper surface 14 of the wing-like portion 12, the inclined surface 33 does not need to be provided.

In addition, in this embodiment, an inclined surface 28 is provided at the portion where the lower end edge of the connecting plate portion 25c of the hook support portion 25 intersects with the end edge of the lower plate portion 25b in the second rotation direction, but the inclined surface 28 does not have to be provided.

In addition, in this embodiment, the hook member 30 is configured with an arm portion 31 and a claw portion 32, but this is not limited thereto, and the hook member 30 may have any shape that is in an engaged state when the casing 20 is rotated in a first rotation direction and in an released state when the casing 20 is rotated in a second rotation direction.

In addition, in this embodiment, the tip side of the hook member 30 is tilted from the normal position to an avoidance position upward in the first rotation direction, but the tilt direction and avoidance position are not limited to this, and it is sufficient that the tip side of the hook member 30 is tilted to an avoidance position located at least on one side of the upward and first rotation direction. For example, the tip side of the hook member 30 may be tilted from the normal position to an avoidance position upward, or the tip side of the hook member 30 may be tilted from the normal position to an avoidance position in the first rotation direction. In other words, the avoidance position may be a position avoided from the rotation trajectory of the wing-like portion 12 of the fin 10 by the force received from the wing-like portion 12.

The present invention has been described above based on the above embodiment, but the present invention is not limited to the contents of the above embodiment, and can be modified as appropriate without departing from the scope of the present invention. In other words, all other embodiments, examples, and operational techniques made by those skilled in the art based on this embodiment are naturally included in the scope of the present invention.

1: Winged steel pipe pile installation device 10: Fin 11: Central portion 12: Wing-like portion 13: Pile connection portion 20: Casing 20a: Lower end portion (one end portion) of casing
20b: Lower end opening of the casing (one side opening)
21: Pile insertion space 23: Inner peripheral surface 23a: Large diameter region 23b: Small diameter region 24: Space 30: Hook member 31: Arm portion 32: Claw portion 33: Inclined surface 34: Lower edge of claw portion (edge on one side in a predetermined direction)
35: Edge of the claw portion in the second rotation direction 40: Confirmation bar (rotation confirmation member)
50: Steel pipe pile 61: Outer casing surface

Claims (7)

A hollow tubular casing extending in a predetermined direction and defining a pile insertion space into which a steel pipe pile can be inserted;
a hook member provided on an outer peripheral surface of one end of the casing in the predetermined direction and supported by the casing so as to be tiltable about a predetermined hook rotation axis;
A fin having a central portion covering one side opening of the one side of the casing, a pile connection portion protruding from the central portion to the other side in the predetermined direction and connectable to the steel pipe pile, and a wing-like portion extending outward from the central portion, and the fin is detachably supported on the casing via the hook member;
The hook member is tiltable about the hook rotation shaft between a normal position in which the hook member extends from the hook rotation shaft side toward the radial outside of the casing and an avoidance position in which a tip side of the hook member is located on at least one side of the other side in the predetermined direction and the first rotation direction of the casing from the normal position,
When the casing is rotated in the first rotation direction with the central portion of the fin covering the one side opening of the casing, the hook member in the normal position is in an engaged state in which the wing-like portion of the fin is engaged, and when the casing is rotated in a second rotation direction opposite to the first rotation direction, the hook member in the normal position is in an engaged state in which the wing-like portion of the fin is released from the engaged state,
In the locked state, the fins rotate in the first rotation direction in association with the rotation of the casing in the first rotation direction, and in the released state, the fins do not rotate even when the casing is rotated in the second rotation direction,
A winged steel pipe pile installation device in which, when the hook member in the released state abuts against the wing-like portion of the fin when the casing is rotated in the second rotation direction, the force from the fin causes the hook member to tilt from the normal position to the avoidance position around the hook rotation axis. the wing-like portion of the fin in the locked state is inclined with respect to a plane perpendicular to the rotation axis of the casing such that an end portion of the wing-like portion of the fin in the first rotation direction is disposed on the one side in the predetermined direction relative to an end portion of the fin in the second rotation direction;
The winged steel pipe pile installation device of claim 1, wherein the hook rotation axis of the hook member extends from the other side of the specified direction toward the first rotation direction of the one side of the specified direction when viewed from the radial direction of the casing, and is inclined with respect to the rotation axis of the casing. the hook member has an arm portion that extends radially outward from the casing side in the normal position, and a claw portion that is bent from a tip of the arm portion toward the one side in the predetermined direction,
A winged steel pipe pile installation device as described in claim 1 or claim 2, wherein the end of the claw portion of the hook member on one side in the specified direction and on the second rotation direction in the normal position is inclined with respect to the edge of the claw portion on one side in the specified direction and the edge of the claw portion in the second rotation direction. The pile connection portion of the fin is formed in a cylindrical shape that allows insertion of the end portion of the steel pipe pile in the predetermined direction,
an inner circumferential surface of the casing has a large diameter region extending from the one side opening to the other side in the predetermined direction, and a small diameter region formed to have a smaller diameter than the large diameter region and extending from the large diameter region to the other side in the predetermined direction,
The large diameter region of the inner circumferential surface of the casing defines a space that allows insertion of the pile connection portion of the fin,
The winged steel pipe pile installation device according to claim 1 , wherein a diameter of the small diameter region of the inner circumferential surface of the casing is formed to be equal to or smaller than an inner diameter of the pile connection portion. A rotation confirmation member is provided which is inserted into the pile insertion space from the other side in the predetermined direction of the casing and is removably supported on the other end of the steel pipe pile in the predetermined direction in a state where the steel pipe pile is inserted into the pile insertion space,
The other end of the rotation confirmation member in the predetermined direction is exposed to the other side in the predetermined direction from the pile insertion space of the casing with the rotation confirmation member supported by the steel pipe pile,
A winged steel pipe pile installation device as described in any one of claims 1 to 4, wherein the rotation confirmation member supported by the steel pipe pile rotates when the steel pipe pile rotates and does not rotate when the steel pipe pile does not rotate. A method for installing a winged steel pipe pile using the winged steel pipe pile installation device according to any one of claims 1 to 4,
a rotary press-in process of rotating the casing and the fins in the engaged state in the first rotation direction to rotary-press them into the ground;
A connection process in which, after the fin reaches a desired position, the rotation is stopped, the steel pipe pile is inserted into the pile insertion space from the other side of the casing, and the steel pipe pile is connected to the pile connection portion of the fin;
and an extraction process of rotating the casing in the second rotation direction and extracting it from the ground while leaving the fin and the steel pipe pile in place. A method for installing a winged steel pipe pile using the winged steel pipe pile installation device according to claim 5,
a rotary press-in process of rotating the casing and the fins in the engaged state in the first rotation direction to rotary-press them into the ground;
A connection process in which, after the fin reaches a desired position, the rotation is stopped, the steel pipe pile is inserted into the pile insertion space from the other side of the casing, and the steel pipe pile is connected to the pile connection portion of the fin;
A confirmation process in which the rotation confirmation member is inserted into the pile insertion space from the other side of the casing and attached to the steel pipe pile, and then the casing is rotated in the second rotation direction to confirm that the fin does not rotate even when the casing is rotated;
and an extraction process of rotating the casing in the second rotation direction and extracting it from the ground while leaving the fin and the steel pipe pile in place.