JP2013108266A - Rotational driving device for spiral reinforcement steep pipe friction pile and screw-in penetration method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational driving device in which a spiral reinforcement steel pipe friction pile that is one of screw-in steel pipe piles is buried underground by penetrating it into the ground, and a screw-in penetration method employing the same.SOLUTION: A rotational driving device for spiral reinforcement steel pipe pile comprises a steel pipe ring having an inner diameter larger than an outer diameter of a spiral reinforcement steel pipe pile, a screw member threaded to a screw part provided in the steel pipe ring at equal intervals, and a nut which is threaded into the screw member at an outer circumferential side of the steel pipe ring to fix the screw member to the steel pipe ring. The screw member has such a length as to be threaded from the outer circumferential side of the spiral reinforcement steel pipe pile through the steel pipe ring, brought into contact with an outer circumference of a pile body of the spiral reinforcement steel pipe pile, and threaded to the steel pipe ring by the nut. A length of the screw member protruding from the steel pipe ring of the rotational driving device for spiral reinforcement steel pipe pile is adjusted to bring the screw member into contact with the outer circumference of the pile body of the spiral reinforcement steel pipe pile, and the steel pipe ring is rotated by matching the steel pipe ring with an axial center of the spiral reinforcement steel pipe pile.

Description

  The present invention relates to a rotary drive device that penetrates and embeds a screw-type steel pipe pile into the ground and a screw-in penetration method using the same, and relates to an apparatus suitable for a spiral reinforced steel pipe friction pile that is one of screw-type steel pipe piles.

  A screw-type steel pipe pile is fed into the ground by the screw action of a member attached along the tip of the steel pipe or the outer peripheral surface of the pile when the steel pipe is rotated. Proposals have been made to attach a wing or to a steel pipe having a length corresponding to the depth in the foundation and spirally wound a steel plate or a reinforcing bar having a constant width (for example, Patent Document 1).

  If screwed steel pipe piles are used as foundation piles, it can be constructed with low vibration, low noise, no soil removal, and after embedding, the support force is obtained by the members attached to the steel pipe piles for screwing, It is frequently used for the foundation work of structures in the civil engineering field.

  When the screwed steel pipe pile is rotated and embedded in the ground, a rotary drive device (for example, Patent Document 2) having a function of gripping the steel pipe and rotating the pile without causing the core misalignment is used.

  Among foundation pile structures, composite piles of soil cement pillars and steel pipe piles are used to replace steel pipe piles with mortar and concrete for cost-effective soil cement. After that, because of the labor involved in embedding the steel pipe pile, a construction method using a screwed steel pipe pile as the steel pipe pile has been proposed for the purpose of improving the construction efficiency and construction cost.

  Patent Document 3 relates to a method of jointly placing a steel pipe pile and a soil cement column. When a steel pipe pile with an excavating stirring blade is embedded in the soil, the steel pipe is excavated and stirred with the blade attached to the tip of the pile. A method is described in which cement milk is spouted from the discharge port provided near the wing of the steel pipe, and the periphery of the steel pipe pile is made of soil cement, so that the steel pipe pile is buried and the soil cement pillar is created simultaneously on the same machine. .

  Patent Document 4 relates to a method for building a soil cement composite pile. When a soil cement column is first drilled by injecting solidified material with a drilling / stirring rod, the compressive strength of the solidified material changes depending on the depth of the drilled hole. The bottom of the soil cement column is made of soil cement using a solidified material with high compressive strength, and a spiral wing is provided at the tip for at least one turn to rotate and advance the steel pipe pile that prevents pile misalignment with respect to the drilling hole. It is described that a spiral blade is embedded in a portion having high compressive strength in the soil cement column.

JP 63-114719 A JP 2000-170164 A JP 2008-175039 A Japanese Patent No. 2731806

  However, the screw-type steel pipe pile used in Patent Documents 3 and 4 has a complicated structure in order to provide a discharge port in the case of Patent Document 3, and in the case of Patent Document 4 in order to lengthen the spiral wing at the tip, In either case, the cost as a core material increases, and the construction cost cannot be sufficiently reduced.

  In addition to the steel pipe pile with excavation stirring blades used in Patent Documents 3 and 4, the screw-in type steel pipe pile is an inexpensive spiral reinforced steel pipe pile (spiral rebar) spirally wound around the outer periphery of the steel pipe. It may be called a type steel pipe friction pile).

  However, since the helical reinforcing bar wound around the outer circumference of the steel pipe is difficult to be gripped by the rotary drive device, and the core misalignment is liable to occur, in the construction methods such as Patent Documents 3 and 4, It is difficult to substitute for a screw-in type steel pipe pile provided at the tip. In the case of the rotary drive device described in Patent Document 2, the rotational torque of the drive motor is transmitted to the cylindrical members attached to the inside and outside of the steel pipe piles that are used depending on the hardness of the soil to be penetrated. The cylindrical member is not attached to the outside of the pile.

  Then, this invention aims at providing the rotational drive apparatus for spiral reinforced steel pipe piles provided with the misalignment prevention function which can embed a spiral reinforced steel pipe pile in the ground, preventing misalignment. .

The object of the present invention can be achieved by the following means.
1. A rotary drive device having a misalignment prevention function for screwing and penetrating a spiral reinforced steel pipe pile into the ground or soil cement without causing misalignment, and a steel pipe ring having an inner diameter larger than the outer diameter of the spiral reinforced steel pipe pile, A screw member that is screwed into a screw portion provided at equal intervals in the steel pipe ring; and a nut that is screwed to the screw member on an outer peripheral side of the steel pipe ring and fixes the screw member to the steel pipe ring. The member has such a length that the steel pipe ring is threaded from the outer peripheral side of the steel pipe ring to contact the outer peripheral portion of the pile body of the spiral reinforced steel pipe pile and is screwed to the steel pipe ring by the nut. Rotation drive device for spiral steel reinforced steel pipe piles having a misalignment prevention function.
2.1 Adjusting the length of the screw member protruding from the steel pipe ring of the rotary drive device for the helical rebar steel pipe pile according to 2.1, contacting the outer periphery of the pile body of the helical rebar steel pipe pile, and the steel pipe ring Threaded penetration of spiral reinforced steel pipe piles that are embedded in the ground or soil cement without rotating the steel pipe ring and aligning the spiral reinforced steel pipe piles after aligning the axis of the spiral reinforced steel pipe piles Construction method.

  According to the present invention, it is possible to embed a spiral reinforced steel pipe friction pile in the ground without causing misalignment, which is extremely useful industrially.

It is a figure explaining the composite pile of a soil cement pillar and a steel pipe pile, (a) is a side view, (b) shows a top view. BRIEF DESCRIPTION OF THE DRAWINGS The figure explaining the structure of the rotational drive apparatus for helical rebar type steel pipe piles concerning this invention. The figure explaining the screw-in construction method which inserts a spiral reinforced steel pipe pile in a soil cement pillar by the rotational drive apparatus for helical reinforced steel pipe piles concerning this invention.

  According to the present invention, the helical rebar type steel pipe pile rotary drive device is adjusted by the length of the screw member threaded through the steel pipe ring so that the rotation center of the device and the pile core of the steel pipe pile coincide with each other, and the screw member is spiral It is characterized by screwing steel pipe piles into the ground or soil cement columns by moving along the reinforcing bars.

  FIG. 1 is a diagram for explaining an example of a composite pile composed of a soil cement column and a spiral reinforced steel pipe pile suitable for application of the present invention, where (a) is a side view and (b) is a plan view. 1 is composed of a soil cement column 2 and a spiral reinforcing bar type steel pipe pile having a spiral reinforcing bar 3 spirally attached to the outer periphery of a pile body 4 made of steel pipe and screwed into the soil cement pillar 2 in the right-handed direction. .

  FIG. 2 is a plan view of a rotational drive device for a helical reinforcing steel pipe pile (hereinafter referred to as a rotational drive device) according to an embodiment of the present invention, and FIG. 3 is a side view thereof and the helical reinforcing steel pipe pile is screwed into the ground. The state of penetration is shown schematically.

  The illustrated rotary drive device 5 uses a steel pipe ring 6 having an inner diameter larger than the outer diameter of the spiral reinforced steel pipe pile as a rotary drive member. The steel pipe ring 6 receives rotational torque from a drive system (not shown). The outer diameter of the spiral reinforcing steel pipe pile is the outer diameter in a state where the spiral reinforcing bar 3 is attached. In the steel pipe ring 6, only the inner diameter is defined, and other dimensions and shapes are appropriately selected according to the material so as to ensure the rigidity to transmit the rotational torque to the spiral reinforced steel pipe pile. However, the outer diameter of which part of the steel pile pile is placed on the hard ground outside the soil cement column 2 so as not to cause misalignment that occurs when the pile axis of the steel pipe pile is tilted from the vertical direction when screwing the steel reinforced steel pipe pile. It is preferable that

  The steel pipe ring 6 has a plurality of screw holes at equal intervals, and the screw member 7 is threaded. The figure shows a state in which the screw member 7 is threaded through the screw hole. The screw member 7 is fixed to the steel pipe ring 6 by a nut 8. In the figure, the nut 8 fixes the screw member 7 on the outer peripheral side of the steel pipe ring 6, but may be further fixed on the inner peripheral side of the steel pipe ring 6. It is preferable that the nut 8 is a double nut because it can be fixed without loosening.

  The length of the screw member 7 protrudes from the inner peripheral side of the steel pipe ring 6 and is in contact with the outer peripheral portion of the steel pipe 4 which is the pile main body of the spiral reinforced steel pipe pile, the length where the nut 8 is screwed, and the screw member 7. The total length of the gripping portions for rotating the. The material and the outer diameter of the screw member 7 are appropriately selected so that the rigidity capable of transmitting the rotational torque of the steel pipe ring 6 to the pile body 4 via the helical rebar 3 can be secured.

  The number of screw holes provided in the steel pipe ring 6 is such that the center of rotation of the steel pipe ring 6 coincides with the pile core, and when the steel pipe ring 6 is rotated, misalignment between the steel pipe ring 6 and the pile body 4 is facilitated. It is preferable to use at least three so as not to occur.

  In the case where the helical reinforcing steel pipe pile is screwed and penetrated into the soil cement column 2 by the rotary driving device according to the present invention, first, the screw member 7 and the helical reinforcing bar 3 are not brought into contact with each other so that they are inside the steel pipe ring 6 of the screw member 7. Adjust the protruding length. Then, the steel pipe ring 6 is appropriately rotated so that the screw member 7 protruding from the steel pipe ring 6 contacts the pile body 4 while avoiding the helical rebar 3.

  Next, the center of rotation of the steel pipe ring 6 coincides with the axis of the pile core spiral reinforced steel pipe pile, and the screw member 7 protrudes to the inside of the steel pipe ring 6 so that the tip of the screw member 7 is in contact with the pile body 4. Adjust the length. At this time, when the steel pipe ring 6 is rotated, the screw member 7 can be rotated along the pile wall of the pile body 4 so that the pile wall is not subjected to pressure so as not to be scratched. The nut 8 is screwed through the screw hole and fixed to the steel pipe ring 6 with the length.

  Thus, when the length which protrudes inside the steel pipe ring 6 of the screw member 7 is adjusted and the steel pipe ring 6 is rotated, the rotation center of the steel pipe ring 6 and the axial center of the pile core spiral reinforced steel pipe pile coincide with each other Thus, the tip of the screw member 7 is hung on the helical rebar 3, and the rotational torque of the steel pipe ring 6 is transmitted to the pile core helical rebar type steel pipe pile.

  As shown in FIG. 3, when screwing and penetrating a spiral reinforced steel pipe pile by turning it clockwise, it is attached so that the helical rebar 3 becomes the right thread of the steel pipe pile, and the steel pipe ring 6 is rotated counterclockwise. . A screw member 7 that hangs on the spiral reinforcing bar 3 screws the spiral reinforcing bar type steel pipe pile into the soil cement column 2 and penetrates it.

  When the spiral reinforced steel pipe pile is screwed and penetrated into the soil cement column 2, if the head of the spiral reinforced steel pipe pile is pressurized, the rotational torque of the spiral reinforced steel pipe pile decreases. Furthermore, the length that the spiral reinforced steel pipe pile penetrates into the soil cement column 2 by pressurization and the length that the spiral reinforced steel pipe pile penetrates by rotation (pitch when the spiral reinforced steel pipe pile is a right-hand thread) ) Is preferably adjusted so that the rotational torque is further reduced.

  According to the present invention, by controlling the rotational speed of the steel pipe ring 6 and the insertion speed of the pile body 4 of the spiral reinforcing steel pipe pile, the rotational angle is close to the angle of attachment of the helical rebar 3 to the pile body 4. It can be embedded, and good adhesion can be obtained between the soil cement pillars.

  According to the present invention, there is an advantage that the steel pipe ring 6 having a certain size can be applied to a spiral reinforcing steel pipe pile having various diameters. In actual construction, the pile body 4 varies in a wide range from φ89.1 (mm) to φ600 (mm), but the length of the screw member is adjusted even if the steel pipe ring 6 is set to a portable level of φ400 (mm). By doing so, it becomes possible to apply.

  According to the rotary drive device according to the present invention, the helical reinforcing bar type steel pipe pile even in the ground where the resistance is higher than that of the soil cement column by adjusting the rotational torque of the steel pipe ring and the vertical pressure applied to the helical reinforcing bar type steel pipe pile. Can be screwed and penetrated without causing misalignment.

DESCRIPTION OF SYMBOLS 1 Composite pile 2 Soil cement pillar 3 Spiral rebar 4 Pile body 5 Rotation drive device 6 Steel pipe ring 7 Screw member 8 Nut

Claims (2)

  A rotary drive device having a misalignment prevention function for screwing and penetrating a spiral reinforced steel pipe pile into the ground or soil cement without causing misalignment, and a steel pipe ring having an inner diameter larger than the outer diameter of the spiral reinforced steel pipe pile, A screw member that is screwed into a screw portion provided at equal intervals in the steel pipe ring; and a nut that is screwed to the screw member on an outer peripheral side of the steel pipe ring and fixes the screw member to the steel pipe ring. The member has such a length that the steel pipe ring is threaded from the outer peripheral side of the steel pipe ring to contact the outer peripheral portion of the pile body of the spiral reinforced steel pipe pile and is screwed to the steel pipe ring by the nut. Rotation drive device for spiral steel reinforced steel pipe piles having a misalignment prevention function.   Adjusting the length of the screw member projecting from the steel pipe ring of the rotary drive device for the helical rebar type steel pipe pile according to claim 1, contacting the outer periphery of the pile body of the helical rebar type steel pipe pile, and the steel pipe ring Threaded penetration of spiral reinforced steel pipe piles that are embedded in the ground or soil cement without rotating the steel pipe ring and aligning the spiral reinforced steel pipe piles after aligning the axis of the spiral reinforced steel pipe piles Construction method.