JP2013011136A - Joint of steel pipe pile for building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint of a steel pipe pile for a building which facilitates connecting operations at a construction site and welding operations in a factory, and also allows the size to be reduced.SOLUTION: When steel pipes are inserted into a joint 10 from upper and lower sides, the steel pipes contact to a ring 20, and at the same time, pieces welded on an inner face of each of the steel pipes push an upper stopper 34 and a lower stopper 44. In this state, when the steel pipes are rotated in a rotation and intruding direction with an auger, each of the pieces is stored respectively in an upper piece storage groove 50 and a lower piece storage groove 60, and also the upper stopper 34 and the lower stopper 44 close an upper stopper guide groove 30 and a lower stopper guide groove 40 respectively. The upper stopper guide groove 30 and the lower stopper guide groove 40 extend in upper and lower axial directions of the ring 20. Consequently, a length of the joint 10 and a thickness of the ring 20 can be made small respectively.

Description

  TECHNICAL FIELD The present invention relates to a joint of a steel pipe pile for construction for adding a rotating penetration type steel pipe pile used as a foundation of a building to a required length, and particularly in connection work at a construction site and in a factory. The present invention relates to a joint that can be easily welded and can be reduced in scale.

  A rotary penetration type steel pipe pile for construction is used by extending a steel pipe having a length that can be conveyed to a required length by adding it at a construction site. First, the first steel pipe provided with the blades is gripped with an auger and rotated and penetrated halfway, and then the lower end of the second steel pipe is connected to the upper end of the first steel pipe. Linking work is done at the construction site, but when welding is involved, the work takes time, special skills are required, and work stops in bad weather, affecting the construction period and The cost was increased. A joint has been proposed that does not require welding in the field and can be connected without special equipment by using the rotational force of the auger. In Japanese Patent Laid-Open No. 2003-90034, when a male part 3 and a female part 4 fitted to the upper and lower two piles 1 and 2 are provided and fitted and rotated, the protrusion 7 of the male part 3 becomes the female part 4. A configuration in which the rotation preventing member 8 using a spring is fixed by moving through the groove 6 and closing the inlet through the axial groove portion 6a of the groove 6 and being fitted into the circumferential groove portion 6b. It is disclosed. In Japanese Patent Laid-Open No. 63-40088, the first casing screw 20 and the second casing screw 30 are provided with claws 22a, 22b, 32c, and 32d, respectively, in the outer cylinder fitting holes 42a to 42d of the joint member 40. The structure which fits and is fixed by inserting the detent | locking member 50 is disclosed. The joint of the type described in Japanese Patent Application Laid-Open No. 2003-90034 requires the male part 3 and the female part 4 to be joined to the steel pipe in advance, and is welded to the heavy long steel pipe laid down in the factory over one round. It took a lot of labor to apply, and required special equipment. In addition, these joints must be constructed so that the joint portion between the steel pipes can withstand the compressive stress similar to that of the steel pipe, and the manufacturing cost has been increased.

JP 2003-90034 JP Japanese Unexamined Patent Publication No. 63-40088

  Accordingly, an object of the present invention is to provide a joint for a steel pipe pile for construction that can be easily connected at a construction site and welded at a factory and can be reduced in scale.

  In order to achieve the above object, the present invention uses at least one piece arranged on the inner peripheral surface near the end of a steel pipe to add a steel pipe pile that rotates and penetrates into the ground until an appropriate length is reached. Therefore, it is a joint of a steel pipe pile for construction that connects an upper steel pipe to a lower steel pipe that is at least partially penetrated into the ground, and the size of the diameter is substantially the same as the outer diameter of the steel pipe, The upper end surface of the steel pipe and the lower end surface of the upper steel pipe are respectively arranged on the lower surface and the upper surface of the circular contact plate, and above and below the contact plate, and are substantially the same as the inner diameter of the steel tube. An insertion cylinder portion having an outer peripheral surface having a diameter, and an opening that extends in the axial direction from the upper side to the lower side of the contact plate closer to the center axis than the contact plate and into which the top of the upper steel pipe can be inserted At least one upper stopper guide groove provided at the upper end; The upper stopper guide groove is shifted in the circumferential direction, is closer to the center axis than the abutment plate, extends in the axial direction from the upper side to the lower side of the abutment plate, and can insert the lower steel pipe piece. An upper hole that is movable along the upper stopper guide groove and at least one lower stopper guide groove provided at the lower end, and is biased in a direction toward the opening of the upper stopper guide groove A stopper, a lower stopper that is movable along the lower stopper guide groove, and a circumferential direction that is the same as the rotational penetration direction of the steel pipe pile from the vicinity of the opening of the upper stopper guide groove. When the lower end surface of the steel pipe is in contact with the upper surface of the contact plate, the upper frame storage groove that can store the upper steel pipe frame, and the rotation of the steel pipe pile from the vicinity of the opening of the lower stopper guide groove Intrusion direction and anti And a lower frame storage groove that can be stored in the lower steel pipe when the upper end surface of the lower steel pipe is in contact with the lower surface of the contact plate. A steel pipe pile joint was constructed.

  In order to connect the joint of the steel pipe pile for construction according to the present invention to the upper end of the lower steel pipe in a state where at least a part of the steel pipe pile penetrates into the ground, and the lower end of the upper steel pipe to be added on the upper part, In the simplest case, the connecting cylinder is started by inserting the insertion tube portion below the joint from the upper end opening of the lower steel pipe in a posture in which the central axes of the both are aligned. If the joint is small, it is manually set, and if the joint is large, the joint is suspended from a crane or the like and set at the upper end of the lower steel pipe. At that time, the angle between the lower steel pipe and the joint is adjusted so that the top arranged on the inner peripheral surface near the upper end of the lower steel pipe coincides with the opening of the lower stopper guide groove in the axial direction. And insert. When the joint is lowered, the piece passing through the opening of the lower stopper guide groove advances while pushing up the lower stopper in the lower stopper guide groove. When the upper end surface of the lower steel pipe contacts the lower surface of the contact plate, the joint stops. Since the lower insertion tube portion includes an outer peripheral surface having an outer diameter substantially the same as the inner diameter of the lower steel pipe, the lower steel pipe and the joint are substantially fixed in the radial direction.

  Next, the upper steel pipe is set to the joint. Typically, the upper end of the upper steel pipe is held by the auger, the upper steel pipe is lowered from directly above the joint set at the upper end of the lower steel pipe, and the upper part of the upper steel pipe is inserted above the joint. Insert the tube. Even at this time, the angle between the upper steel pipe and the joint is such that the piece arranged on the inner peripheral surface near the lower end of the upper steel pipe coincides with the opening of the upper stopper guide groove in the axial direction. Is adjusted. As a result, the top passes through the opening of the upper stopper guide groove, advances through the lower stopper guide groove while pushing the upper stopper downward, and when the lower end surface of the upper steel pipe contacts the upper surface of the contact plate, the upper steel pipe Stops. As a result, the upper steel pipe and the joint are fixed in the radial direction.

  When the auger is operated and the upper steel pipe is rotated in the rotational penetration direction of the steel pipe pile with the abutment plate sandwiched between the upper end face of the lower steel pipe and the lower end face of the upper steel pipe, it is attached to the upper steel pipe. The top also rotates in the rotational penetration direction, and enters the upper top storage groove provided continuously in the same circumferential direction as the rotational penetration direction of the steel pipe pile from near the opening of the upper stopper guide groove. As a result, the upper stopper that has been pushed in by the frame slides in the direction toward the opening due to the bias, closes the boundary between the upper frame storage groove and the upper stopper guide groove, and the frame returns to the upper stopper guide groove side. To prevent. The top stopper is covered so that the top is stored in the top storage groove and does not return to the upper stopper guide groove side, so that the upper steel pipe and the joint are in the axial direction (vertical direction) and circumferential direction (center). Fixed in the direction of rotation around the axis).

  Further, when the upper steel pipe is rotated in the rotational penetration direction by the auger, the joint fixed to the upper steel pipe is also rotated in the rotational penetration direction. When the joint rotates in the rotational penetration direction, the frame attached to the lower steel pipe rotates relative to the joint in the circumferential direction opposite to the rotational penetration direction, and the rotational penetration penetrates from near the opening of the lower stopper guide groove. It enters the lower frame storage groove provided continuously in the circumferential direction opposite to the direction. Then, the lower stopper pushed up by the frame falls and the frame cannot return to the upper stopper guide groove side. Thereby, both the joint and the lower steel pipe are fixed in the axial direction and the circumferential direction, and therefore the upper steel pipe and the lower steel pipe are fixed and connected in any of the axial direction, the circumferential direction and the radial direction via the joint. . The above connection procedure is an example. For example, in the case of a small-diameter steel pipe pile for construction, the work until the joint is set on the lower steel pipe and rotated to fix the joint to the lower steel pipe is performed by a construction worker. May be performed manually first, and then the upper steel pipe is set on the joint and the upper steel pipe is rotated by the auger.

  As described above, in the joint of a steel pipe pile for construction according to the present invention, the processing applied to the steel pipe to be connected is only the work of mounting the top on the inner peripheral surface near the end of the steel pipe, and the factory (or the construction site) ) Is easy. And since each stopper guide groove was comprised so that it might extend in the axial direction from the upper direction of a contact plate to the downward direction, the lower end of an upper steel pipe and the upper end of a lower steel pipe can be connected in the very close position. Thereby, the thickness of the contact plate which receives the compressive stress related to the steel pipe pile can be reduced as much as possible. Therefore, the size of the joint is suppressed, and members other than the contact plate do not need high strength. In the joint according to the present invention, the abutting plate is the only part to which compressive stress is applied. Therefore, it is necessary to use a material having high strength such as SS material (rolled steel for general structure) or STK material (carbon steel pipe for general structure). Therefore, the manufacturing cost can be saved by reducing the thickness of the contact plate. The thickness of the abutting plate depends on the scale of the steel pipe pile, but it is sufficient if it can withstand the weight of the joint when the joint is placed on the upper end of the lower steel pipe, for example, about 0.5 to 2.0 cm Is enough. Preferably, the upper stopper guide groove and the lower stopper guide groove have substantially overlapping heights in the axial direction at both ends. By adjusting the positions and lengths of the upper stopper guide groove and the lower stopper guide groove in this way, the size of the joint can be minimized, and in particular, the thickness of the contact plate can be minimized. it can.

  The top is an iron bar formed in a U shape that opens toward the adjacent end of the steel pipe, and may be configured such that welding is performed on the inner portion of the U shape. If welding is performed on the outside of the frame, the outer shape of the frame protrudes and the weld metal rises to the outside, which may cause a problem that it cannot be stored in the frame storage groove or the stopper cannot be returned. If the U-shape of the frame is open toward the adjacent end of the steel pipe, welding work can be performed from the open end of the steel pipe. The contact plate may be formed so that the thickness gradually decreases from the outer edge toward the center. By forming the contact plate in this way, the contact plate receives a larger compressive stress at a portion closer to the inner peripheral surface of the steel pipe. become. Therefore, when a large compressive stress is applied to the steel pipe pile, the deformation and breakage of the end of the steel pipe that is in contact with the contact plate spreading outward in the radial direction is less likely to occur. Further, the abutting plate is separate from other members constituting the joint and can be exchanged, whereby it is possible to deal with steel pipes having different thicknesses. The exchangeable contact plate has, for example, a C-ring shape. Further, the abutment plate may be provided with a cylindrical bag portion projecting from the outer edge in the vertical direction of the upper and lower sides, so that the clearance between the upper and lower steel pipes and the joint (that is, the inner peripheral surface of the steel pipe and the joint) The backlash due to the provision of the clearance between the insertion tube portion and the insertion tube portion can be suppressed.

  As described above, according to the joint of the steel pipe pile for construction according to the present invention, the work at the construction site and the factory is easy, and the scale of the joint is small, so that the work efficiency can be improved and the cost is reduced. Can be reduced.

FIG. 1 is a perspective view showing one embodiment of a joint of a steel pipe pile for construction according to the present invention. FIG. 2 is a perspective view of the joint of the steel pipe pile for construction shown in FIG. 1 viewed from the opposite side. FIG. 3 is a plan view showing a joint of the steel pipe pile for construction shown in FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 5 is a cross-sectional view taken along the line VV in FIG. 6 is a sectional view taken along line VI-VI in FIG. FIG. 7 is a perspective view showing a steel pipe that fits the joint of the steel pipe pile for construction shown in FIG. 1, and shows a shortened length. FIG. 8 is a plan view showing the steel pipe of FIG. 9 (a) and 9 (b) are enlarged cross-sectional views showing a ring in another embodiment of FIG. 1, and the thickness of each member is exaggerated for convenience of explanation of the invention. 10 (a) to 10 (i) are perspective views for explaining a steel pipe connecting process by the joint of FIG. 1, and a part of the steel pipe is omitted.

  Hereinafter, the best mode of the joint of the steel pipe pile for construction concerning the present invention is explained in detail, referring to drawings. The following description is for the purpose of understanding the invention more deeply and is not intended to limit the scope of the claims.

  1-6 shows one Embodiment of the joint of the steel pipe pile for construction which concerns on this invention. In each figure, the joint 10 is used to connect the upper steel pipe to the lower steel pipe penetrated into the ground, leaving the upper end, in order to add the rotary penetration type steel pipe pile until reaching an appropriate length. Is done. A blade is attached to the tip of the lowermost steel pipe, and it penetrates into the ground by rotating the blade. 7 and 8 show steel pipes connected by the joint according to the present embodiment. On the inner peripheral surface near both ends of the steel pipe 70, the steel pipe 70 is welded to the inner peripheral surface at a position shifted by 180 degrees. The welding operation is usually performed at the factory before being carried to the construction site, but it may be performed at the construction site. Each of the tops 72 and 74 is made of a steel bar formed in a U-shape that opens toward the adjacent end of the steel pipe 70, and welding is performed on the U-shaped inner portion. This is because, for example, if the frame is a square plate, if the outer edge of the frame is welded, the outer shape of the frame protrudes and the weld metal rises to the outside. As a result, the frame cannot be stored in the frame storage groove or the stopper cannot be returned. May occur. Further, if the U-shape of each of the tops 72 and 74 is open toward the adjacent end of the steel pipe, the welding operation can be easily performed from the open end of the steel pipe. The tops 72 and 74 are used when the steel pipe pile is rotated and penetrated by an auger (not shown). The joint 10 is made of cast iron.

  A ring 20 is fitted into the ring groove 12 that is intermittently provided around the axial center of the joint 10. The size of the outer diameter of the ring 20 is substantially the same as the outer diameter of the steel pipe 70, and the upper end surface of the lower steel pipe and the lower end surface of the upper steel pipe are in contact with the lower surface and the upper surface, respectively. The ring 20 is a so-called C-ring, and one ring-shaped portion is cut away. Since the ring 20 is made of SS material and has elasticity, the notch is widened, the entire inner diameter is enlarged and the joint 10 is passed through and moved to a position matching the ring groove 12, and then the notch is restored. Thus, the ring groove 12 can be fitted. The cross section of the ring 20 is rectangular, and the upper surface and the lower surface are formed flat in order to abut against the flat end surface of the steel pipe 70 and uniformly support the compressive stress.

  The radial width of the ring 20 protruding from the ring groove 12 is substantially the same as the thickness of the steel pipe 70 connected by the joint 10. In the present embodiment, since the ring 20 can be exchanged, the difference between the inner diameter and the outer diameter of the ring 20 can be appropriately selected according to the wall thickness of the steel pipe 70, and therefore a steel pipe within a certain range. A wall thickness of 70 can be accommodated. In another embodiment, as shown in FIG. 9A, the cross section of the ring 22 is formed such that the axial thickness gradually decreases from the outer edge toward the center. As a result, a larger compressive stress is applied to the portion closer to the inner peripheral surface of the steel pipe 70, and therefore, when a large compressive stress is applied to the steel pipe pile, the deformation of the end of the steel pipe 70 that is in contact with the ring 22 expands radially outward.・ It is hard to break. In yet another embodiment, as shown in FIG. 9B, the ring 24 includes a cylindrical bag portion 26 protruding from the outer edge in the vertical axis direction. The diameter of the inner peripheral surface of the bag portion 26 is substantially equal to the diameter of the outer peripheral surface of the steel pipe 70, thereby suppressing backlash between the joint 10 and the steel pipe 70.

  In the joint 10, the insertion tube portion 14 is disposed above and below the ring 20. The general shape of the joint 10 is a cylindrical shape and has an outer diameter that is substantially the same as the inner diameter of the steel pipe 70 (that is, slightly smaller than the inner diameter of the steel pipe 70 to ensure clearance when the joint 10 is inserted into the steel pipe 70). A portion having a surface corresponds to the insertion tube portion 14. The insertion cylinder part 14 is intermittently arrange | positioned on the outer peripheral surface of the part in which each stopper guide groove | channel which is mentioned later, each frame | top storage groove | channel, etc. are not provided. A portion near the central axis of the joint 10 is hollow, and the upper surface and the lower surface are open.

  An upper stopper guide groove 30 extends in the axial direction from the upper side to the lower side of the ring 20 closer to the center axis than the ring 20. The upper stopper guide groove 30 is provided with an opening 32 at the upper end through which one piece 72 of the upper steel pipe 70 can be inserted. The lower stopper guide groove 40 extends in the axial direction from the upper side to the lower side of the ring 20 closer to the center axis than the ring 20 at a position shifted in the circumferential direction from the upper stopper guide groove 30. An opening 42 into which the frame 72 can be inserted is provided at the lower end. Each stopper guide groove 30, 40 has a ring 20 disposed substantially at the center in the axial direction, and the upper and lower ends in the axial direction are substantially at the same height.

  The upper stopper 34 is movable along the upper stopper guide groove 30 and is urged by a spring 36 in a direction toward the opening 32 of the upper stopper guide groove 30. Both ends of the spring 36 are provided with a hole 16 provided at an end opposite to an end provided with the opening 32 of the upper stopper guide groove 30, and a hole 38 opened at a lower end facing the hole 16 of the upper stopper 34. It is inserted and fixed. As shown in FIG. 3, the width of the upper stopper 34 is slightly smaller than the width of the opening 32 of the upper stopper guide groove 30, so that the upper stopper 34 does not pass through the opening 32.

  The lower stopper 44 is movable along the lower stopper guide groove 40, and the width of the lower stopper 44 is slightly smaller than the width of the opening 42 of the lower stopper guide groove 40. Since the lower stopper 44 is pulled downward due to the attractive force, no spring is provided to urge the lower stopper 44 in the direction toward the opening 42 of the lower stopper guide groove 40, but in other embodiments A spring may be attached to reliably return the lower stopper 44.

  The upper frame storage groove 50 is provided continuously from the vicinity of the opening 32 of the upper stopper guide groove 30 in the same circumferential direction as the rotation penetration direction of the steel pipe pile. The upper frame storage groove 50 can store the frame 72 of the upper steel pipe 70 at a position where the lower end surface of the upper steel pipe 70 is in contact with the upper surface of the ring. That is, the height and width of the upper frame storage groove 50 are It is formed substantially the same as the frame 72. Therefore, the top 72 is inserted into the upper piece storage groove 50 and the upper stopper 34 is returned to the vicinity of the opening 32 of the upper stopper guide groove 30 to prevent the piece 72 from returning toward the upper stopper guide groove 30. Then, the top 72 is fixed in the upper top storage groove 50 and can hardly move relatively in the axial direction and the circumferential direction.

  The lower frame storage groove 60 is provided continuously from the vicinity of the opening 42 of the lower stopper guide groove 40 in the circumferential direction opposite to the rotational penetration direction of the steel pipe pile. The lower frame storage groove 60 can store a lower steel pipe frame 72. When the space between the lower stopper guide groove 40 and the lower stopper 44 is blocked by the lower stopper 44, the frame 72 is fixed in the lower frame storage groove 60. Is done. Of course, in practice, a clearance of a necessary size is provided between each frame 72 and each frame storage groove 50, 60, and there is some backlash, but this is mainly required for steel pipe piles for construction. Since it is a compressive stress, it will be apparent to those skilled in the art that undue strictness is not required for both sizes.

  As shown in FIG. 2, at a position shifted 180 degrees from each stopper guide groove 30, 40 of the joint 10, a piece disposed on the inner peripheral surface of the steel pipe 70 at a position shifted 180 degrees from the piece 72. An L-shaped piece passage groove 16 and an inverted L-shaped piece passage groove 18 are provided so that 74 can proceed without interfering with the connecting operation.

  Next, the operation of the embodiment of FIG. 1 will be described with reference to FIG. In FIG. 10, for the sake of explanation, the lower steel pipe is denoted by reference numeral 80, and the frame attached to the lower steel pipe 80 is denoted by reference numeral 82.

  First, as shown in FIG. 10A, the joint 10 is disposed immediately above the lower steel pipe 80. The lower steel pipe 80 is in a state where its lower part is rotationally inserted into the ground (not shown) and its upper part projects about 1 m above the ground. A blade for rotational penetration is attached to the lower end of the lower steel pipe 80 or a steel pipe connected to the lower side of the steel pipe 80, and is penetrated into the ground by being rotated around an axis line by an auger (not shown). The rotation direction is clockwise in plan view, and this rotation direction is referred to as a rotation penetration direction.

  After the joint 10 is arranged directly above the steel pipe 80 in such a manner that the steel pipe 80 and the central axis coincide with each other and the opening 42 of the lower stopper guide groove 40 and the top 82 are overlapped in the axial direction, The joint 10 is lowered. In FIG. 10A, the top 82 passes through the opening 42, and the upper U-shaped upper end of the top 82 is in contact with the lower end of the lower stopper 44. In addition, the joint 10 in FIG. 10 is small, and has a weight and a size that can be lifted manually by a construction worker, positioned right above the steel pipe 80, lowered, and rotated.

  10B, the joint 10 is lowered, the lower part of the joint 10 is inserted into the steel pipe 80 from the upper end of the steel pipe 80, the lower surface of the ring 20 is in contact with the upper end face of the steel pipe 80, and the joint 10 is Indicates a stopped state. The top 82 enters the lower stopper guide groove 40, and the lower stopper 44 pushed up by the top 82 slides near the upper end of the lower stopper guide groove 40. In this state, the frame 82 and the lower frame storage groove 60 are located at substantially the same height. Since the insertion cylinder part 14 has an outer peripheral surface substantially the same as the diameter of the inner peripheral surface of the steel pipe 80, the joint 10 and the steel pipe 80 are fixed in the radial direction.

  As shown in FIG. 10C, when the joint 10 is rotated in the rotational penetration direction around the axis from the state of FIG. 10B, the piece 82 rotates in the direction opposite to the rotational penetration direction with respect to the joint 10. Therefore, the frame 82 enters the lower frame storage groove 60. When the joint 10 is further rotated, the frame 82 is completely stored in the lower frame storage groove 60 as shown in FIG. At the same time, the lower stopper 44 that has lost its support falls in the lower stopper guide groove 40. FIG. 10E shows a state in which the lower stopper 44 is slid and stopped until it reaches the lower end of the lower stopper guide groove 40. In this state, the upper and lower ends in the axial direction and the left and right sides in the circumferential direction of the top 82 are substantially in contact with the upper and lower ends and the right side of the lower top storage groove 60 and the right side of the lower stopper 44, respectively. Is fixed in the axial direction and the circumferential direction. Although not shown, the piece 84 on the opposite side of the piece 82 that is shifted by 180 degrees passes through the piece passage groove 18 and is located in the back of the inverted L-shaped horizontal passage.

  Next, the upper steel pipe 70 is fixed to the upper part of the fixed joint 10 in which the lower part is inserted into the lower steel pipe 80. As shown in FIG. 10 (f), the upper end of the upper steel pipe 70 is held and suspended by an auger (not shown) and lowered from directly above the joint 10. At that time, the relative angles of the joint 10 and the steel pipe 70 are adjusted so that the axes of the joint 10 and the steel pipe 70 are the same, and the position of the top 72 coincides with the opening 34 of the upper stopper guide groove 30.

  The steel pipe 70 is lowered from the position of FIG. 10 (f) by operating the auger, and the top 72 passing through the opening 34 pushes down the upper stopper 34 against the bias of the spring 36. When the steel pipe 70 is further lowered, the lower end surface of the steel pipe 70 comes into contact with the upper surface of the ring 20 as shown in FIG. At this time, the upper stopper 34 slides until reaching the lower end of the upper stopper guide groove 30, and the top 72 is positioned at the same height as the upper top storage groove 50. The joint 10 and the steel pipe 70 are fixed in the radial direction by the insertion tube portion 14 having an outer peripheral surface substantially the same as the diameter of the inner peripheral surface of the steel pipe 70.

  Subsequently, when the steel pipe 70 is rotated in the rotational penetration direction by operating the auger, the top 72 is also moved in the rotational penetration direction, and enters the upper top storage groove 50 as shown in FIG. When the frame 72 is completely stored in the upper frame storage groove 50, the upper stopper 34 pressed by the frame 72 is pushed up by the spring 36 as shown in FIG. It is slid back to the original position near the opening 32. The upper stopper 34 restricts the movement of the top 72 toward the upper stopper guide groove 30, and thus the relative movement of the joint 10 and the steel pipe 70 in the axial direction and the circumferential direction rotating around the axis is restricted. The The top 74 arranged at a position shifted by 180 degrees from the top 72 moves in the top passage groove 17 and reaches the back of the L-shaped horizontal passage.

  According to the joint 10 according to the present embodiment, the upper steel pipe 70 and the lower steel pipe 80 are connected via the joint 10 through the above-described steps, and are rotated and penetrated by the auger. Accordingly, a steel pipe is further connected to the upper end of the upper steel pipe 70. The processing applied to the steel pipes 70, 80 before the connecting operation is only welding the frames 72, 74, 82, 84. For example, as in the past, the male and female dies of the joint are formed around the open end of the steel pipe. Compared to welding work, it is much easier and can be done in a short time. Of course, it is possible to perform the welding work of the piece at the construction site, but in any case, it is easy and short, and for example, if a guide for determining the welding position of the piece by fitting into the open end of the steel pipe is used, It can be easily and accurately welded. The ring 20 is the only part to which the compressive stress is applied in the joint 10 and is made of SS material, while the other members (except the spring 36) of the joint 10 are made of cast iron. In addition, the ring 20 must use a high-quality steel material that can be used as a structural member of a building such as an STK material or an SM material (rolled steel for welded structure), but other members may be cast iron or cast steel. Although the thickness of the ring 20 depends on the scale of the steel pipe pile, it is sufficient that the weight of the joint 10 can be supported when the joint 10 is placed on the upper end of the lower steel pipe 80, for example, 0.5 to 2.0 cm. About enough.

  Further, according to the joint 10, the upper stopper guide groove 30 and the lower stopper guide groove 40 extend in the axial direction from the upper side to the lower side of the ring 20, and the lower end of the upper steel pipe 70 and the upper end of the lower steel pipe 80 are the ring 20. It is connected at a very close position, with a pinch in between. Therefore, the ring 20 that receives the compressive stress applied to the steel pipe pile has an advantage that the thickness of the ring 20 is reduced as much as possible to reduce the size of the joint 10 as a whole, and members other than the ring 20 do not require high strength. This makes it possible to reduce the size of the joint 10, so that it is possible to improve the working efficiency and reduce the manufacturing and working costs.

  In order to minimize the length of the joint 10 in the axial direction, in the present embodiment, the upper stopper guide groove 30 and the lower stopper guide groove 40 have substantially the same height in the axial direction at both ends. Designed to be If the positions and lengths of the upper stopper guide groove 30 and the lower stopper guide groove 40 are adjusted in this way, the size of the joint can be minimized, particularly between the upper steel pipe 70 and the lower steel pipe 80. Thus, the thickness of the ring 20 supporting the compressive stress can be minimized. Each stopper guide groove 30, 40 has an axial length approximately double that of each stopper 34, 44 and each frame, and the ring 20 is substantially at the center in the axial direction of each stopper guide groove 30, 40. Arrangement is another design that contributes to downsizing. The yield strength against the tensile stress and torsional stress generated in the steel pipe pile can be adjusted by designing the strength of welding of the top 72 and the strength of the top housing grooves 40 and 50 and the stoppers 34 and 44.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it is needless to say that modifications can be appropriately made within the scope of the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Joint 14 Insertion cylinder part 20 Ring 30 Upper stopper guide groove 32 Opening hole 34 Upper stopper 36 Spring 40 Lower stopper guide groove 42 Opening hole 44 Lower stopper 50 Upper top storage groove 60 Lower top storage groove 70 Steel pipe 72, 74 top

Claims (7)

In order to add a steel pipe pile that rotates and penetrates into the ground by using at least one piece arranged on the inner peripheral surface near the end of the steel pipe until it reaches an appropriate length, at least partly penetrates into the ground A steel pipe pile joint for building connecting the upper steel pipe to the lower steel pipe,
The diameter of the diameter is substantially the same as the outer diameter of the steel pipe, and the upper end surface of the lower steel pipe and the lower end surface of the upper steel pipe are respectively circular contact plates that contact the lower surface and the upper surface,
An insertion tube portion that is disposed above and below the contact plate and has an outer peripheral surface having an outer diameter substantially the same as the inner diameter of the steel pipe;
At least one upper stopper guide that is provided near the center axis of the abutment plate and extends in the axial direction from above to below the abutment plate and into which an upper steel pipe piece can be inserted. Groove,
The upper stopper guide groove is shifted in the circumferential direction, is closer to the center axis than the abutment plate, extends in the axial direction from the upper side to the lower side of the abutment plate, and the frame of the lower steel pipe can be inserted. At least one lower stopper guide groove provided with an opening at the lower end;
An upper stopper that is movable along the upper stopper guide groove and is urged in a direction toward the opening of the upper stopper guide groove;
A lower stopper that is movable along the lower stopper guide groove;
When the upper stopper guide groove is continuously provided in the same circumferential direction as the rotational penetration direction of the steel pipe pile from the vicinity of the opening, and the lower end surface of the upper steel pipe is in contact with the upper surface of the contact plate An upper frame storage groove capable of storing the upper steel pipe frame;
When the lower stopper guide groove is continuously provided in the circumferential direction opposite to the rotational penetration direction of the steel pipe pile from the vicinity of the opening, and the upper end surface of the lower steel pipe is in contact with the lower surface of the contact plate A steel pipe pile joint for construction, comprising: a lower frame storing groove capable of storing the lower steel pipe frame. 2. The building steel pipe pile according to claim 1, wherein the top is a U-shaped iron bar that opens toward an adjacent end of the steel pipe, and welding is applied to a U-shaped inner portion. Joint. The steel pipe pile joint for building according to claim 1, wherein the upper stopper guide groove and the lower stopper guide groove have substantially overlapping heights in the axial direction at both ends. The steel pipe pile joint for building according to claim 1, wherein the contact plate is formed so that the thickness gradually decreases from the outer edge toward the center. The said contact plate is a joint of the steel pipe pile for construction of Claim 1 which is a different body from the other member which comprises a joint, and is replaceable. The steel pipe pile joint for building according to claim 5, wherein the contact plate has a C-ring shape. The said contact plate is a joint of the steel pipe pile for construction of Claim 1 containing the cylindrical bag part protruded in the up-down axial direction from the outer edge.