JP6502915B2 - Connection method of steel pipe piles - Google Patents

Description

  The present invention relates to a method of connecting steel pipe piles that can connect the lower steel pipe pile and the upper steel pipe pile that is externally fitted to the lower steel pipe pile by an operation from one side.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2001-64959) can firmly hold a lower end of the lower pile with a hydraulic machine or the like without damaging the upper end, and further screw the lower end of the upper pile to the upper end of the lower pile. Provided is a steel pipe pile, a lower pile and an internal thread unit member capable of easily attaching the internal thread unit member to the upper end portion of the lower main body pipe without damaging the lower pile head when coupling and coupling together And the tube portion of the inner peripheral screw in which the unit member attached to the upper end portion of the lower pile main body tube is firmly fitted inward of the upper end peripheral wall of the lower pile main body tube, and this cylindrical portion The projection is integrally connected to the upper end portion of the lower pile main body pipe and has an overhang portion projecting to the upper end face side of the peripheral wall of the lower pile main body pipe, and is integrally joined with the lower pile main body pipe by welding.

  Patent Document 2 (Japanese Patent Application Laid-Open No. 2001-64962) can solve the problem that occurs when connecting upper and lower piles by on-site welding or a screw type unit, and further reduce the mechanical load on the bolt. It is possible to firmly connect the upper and lower piles with a small number of bolts, and prevent the connection between the lower pile and the upper pile from protruding largely outward, thereby smoothly penetrating the ground. To provide a steel pile having a structure capable of connecting the end plates to be connected to the pile ends, the connecting plates, and the connecting plates such that the connecting plates are spaced in a predetermined dimension in the end plate or pile axial direction. Disclosed is a unit member made of one having a connecting foot, which bolt-joins upper and lower piles.

  In patent document 3 (Japanese Patent Application Laid-Open No. 2003-105755), different diameter steel pipe piles can be easily connected by screw unit members to shorten the construction time, and advanced welding technology is not required, and it is not influenced by weather. An upper screw provided at the upper end of the lower steel pipe pile, which provides a unit structure between different diameter steel pipe piles that can be constructed and can exhibit stable unit performance where stress can be transmitted smoothly from the upper steel pipe pile to the lower steel pipe pile. A fitting portion having an inner diameter larger than the outer diameter of the lower steel pipe pile is formed on the lower surface side of the unit member, and the upper steel pipe pile and the upper screw unit member are fitted with the upper end of the lower steel pipe pile fitted in the fitting portion. A unit structure is disclosed in which an external screw of the lower screw unit member provided at the lower end of the upper steel pipe pile is screwed and connected to the internal screw of the upper screw unit member.

  Patent Document 4 (Japanese Patent Application Laid-Open No. 2008-25156) provides a steel pipe pile of different diameter which can be constructed by a rational and economical joining method of a spread-out pile excellent in earthquake resistance, A piling material for connecting a piling material having a diameter smaller than that, and the first end portion having the same diameter capable of being connected to the piling material having the large diameter, and the same piling material capable of being connected to the piling material having the small diameter A first straight pipe portion and a second straight pipe portion are provided in the longitudinal center direction from each of the first end portion and the second end portion, and a second straight pipe portion is provided from the first straight pipe portion Disclosed is a different diameter steel pipe pile having a diameter-reduced portion whose diameter decreases toward the straight pipe portion.

  When building on soft ground, a pile foundation is generally adopted to support the building. In this case, it is required that the lower steel pipe pile (lower pile) having a cutting blade, a digging claw, and a spiral blade attached to its tip be rotationally propelled by a rotational drive device and installed on the ground. Furthermore, there is known a method in which an upper steel pipe pile (upper pile) is connected to the upper portion of the lower pile, and it is further rotationally propelled to be installed deep in the ground.

  In addition, the steel pipe pile has a role to support the load of the upper structure over a long period of time, and the load (horizontal force) applied to the steel pipe pile from the lateral direction in the part close to the ground generated in a relatively short period of time such as an earthquake. Have a role to This horizontal force decreases as it gets deeper and deeper as it approaches the ground surface, so it is not necessary to form the entire steel pipe pile with the same cross-sectional area. For this reason, the structure of the part near the ground surface increases its projected area, and mainly the part subjected to vertical load only needs to withstand compression and buckling, so the cross-sectional area of the upper pile is large, and the lower pile is cut off. It is desirable in terms of cost to reduce the area.

  Patent Document 4 discloses a different diameter steel pipe pile for connecting a large diameter pile material and a small diameter pile material to correspond thereto. However, as disclosed in Patent Document 1, after installing the lower pile on the ground, in order to weld the lower pile and the different diameter steel pipe pile, and further, the different diameter steel pipe pile and the upper pile on site, There is a problem that good quality welding is difficult when the wind is strong. In particular, when welding different diameter steel pipe piles to the lower pile and when welding the upper pile to the upper end of the diameter steel pipe pile, it is necessary to hold the different diameter steel pipe pile or upper pile located above during welding. However, there is a problem that accuracy control in the vertical direction (verticality) is difficult.

  In order to solve the above problems, the inventor of the present invention can improve not only the steel pipe piles of different or equal diameter but also the verticality at the time of joining and facilitate the joining operation (welding or bolt crimping). In order to provide the steel pipe pile unit structure which can be carried out, the fixing mechanism used by the unit structure indicated by Example 5 of patent documents 5 (JP, 2013-234561, A) was invented.

  The fixing mechanism includes a truncated cone-shaped top portion attached to a frusto-conical lock hole formed through the top and bottom piles in the connecting portion of the top and bottom piles, and a portion engaged with the top portion The head of the fixing bolt is engaged with the mounting recess formed in the frame portion by screwing the fixing bolt into the nut and tightening it, and the peripheral wall of the mounting recess protrudes outward. It is made to fix a top part to a lock hole by making it. By this, the above-mentioned subject can be achieved.

  However, the above-described fixing mechanism has an effect that the construction of the unit can be performed in a place where the welding work can not be performed or a place where the welding work is difficult, and has an effect that the construction time can be shortened. Furthermore, it has the effect of being effective against the force in the compression / extraction / bending direction, but since the peripheral wall of the mounting recess of the top part is deformed and in close contact with the lock hole, remove it once it is used Had the drawback of being difficult.

  Therefore, the applicant has proposed a steel pipe pile unit structure having a fixing mechanism having a detachable structure in Japanese Patent Application No. 2014-175462. In this steel pipe pile unit structure, a truncated cone shaped lock hole having a diameter reduced toward the central direction formed at the connection portion of the lower steel pipe pile and the upper steel pipe pile, and a truncated cone shaped taper lock corresponding to the lock hole Part, a fixed washer part arranged on the inner surface of the steel pipe pile of the taper lock part, a tightening washer part fitted in the fixed washer part to expand the diameter of the fixed washer part, and a fixed washer part And a nut for tightening the high-strength bolt, and rotating the nut to tighten the bolt. Thus, the tightening washer portion is penetrated into the fixed washer portion to expand the diameter, the taper lock is fixed to the lock hole, and the upper steel pipe pile and the lower steel pipe pile are connected. Rukoto in which it becomes possible.

JP, 2001-64959, A Unexamined-Japanese-Patent No. 2001-64962 JP 2003-105755 JP 2008-25156 A JP, 2013-234561, A

  The present invention provides a method of connecting steel pipe piles in which the lower steel pipe pile and the upper steel pipe pile externally fitted to the lower steel pipe pile can be connected by an operation from one side. It is a thing.

Therefore, in the method of connecting steel pipe piles according to the present invention, in order to connect the lower steel pipe pile and the upper steel pipe pile fitted to the lower steel pipe pile, the lower steel pipe pile and the upper steel pipe pile Forming a frusto-conical lock hole in which the small diameter opening at the inner end and the large diameter opening at the outer end communicate with each other at the connecting portion; and a small diameter front end and a large diameter rear end corresponding to the lock hole A tapered lock having a bolt through hole in the central axis direction, and a fixed washer having an outer diameter substantially equal to that of the small diameter opening and being in contact with the small diameter tip of the taper lock And a tightening washer which is fitted into the fixing washer to expand the diameter of the fixing washer, and a fastening means which is disposed through the bolt through hole and tightens the fastening washer to be fitted into the fixing washer. By The taper lock unit which is, that the fixing washer is attached to the lock hole from the large diameter opening side so as to be positioned on the small diameter opening of the locking hole, and, by the tightening means, fixing the clamping washer By inserting the washer into the washer and expanding the diameter of the fixing washer, the fixing washer bites into the periphery of the small diameter opening of the lock hole to fix the taper lock unit in the lock hole. Preferably, the fastening means is constituted by a bolt disposed through the bolt through hole and a nut engaged with the bolt from the outer end of the taper lock.

  Furthermore, the fixing washer has an annular shape and has an outer diameter substantially equal to the small diameter opening of the lock hole, and the inner peripheral surface thereof is reduced in diameter from the side where the tightening washer is mounted to the opposite side An inner tapered surface is formed. Further, correspondingly, the tightening washer is formed with a tapered outer tapered surface corresponding to the tapered surface of the fixed washer, and the outer tapered surface is fixed by being gradually inserted into the fixed washer. In order to push the inner tapered surface of the washer radially outward, the fixing washer is spread and engaged with the small diameter opening peripheral portion of the lock hole, the taper lock unit is fixed to the lock hole, and the inner and outer plates are It is fixed.

  The connecting portion is constituted by an inside cylinder welded and fixed to the upper portion of the lower steel pipe pile, and an outside cylinder welded and fixed to the lower portion of the upper steel pipe pile and externally fitted to the inner cylinder. The lock holes may be formed through the connection portion, and a plurality of lock holes may be uniformly formed around the connection portion. Since the taper lock unit can be fixed to the lock hole as described above by mounting the taper lock unit and tightening the nut in each lock hole formed in this connection portion, the lower steel pipe pile and the upper steel pipe pile are It can be linked. Furthermore, it can be fixed firmly to the rotational moment acting on the inside cylinder and the outside cylinder.

  Further, it is preferable that a rotation fixing prevention portion for fixing the rotation of the bolt is formed at an end of the bolt on which the nut is screwed.

  Since the fixing bolt portion can be firmly fixed by the rotation fixing holding portion, the rotation of the nut is facilitated, and the fixing bolt portion can be easily tightened. Further, the rotation fixing holding portion is held when the nut is rotated, and a groove-like neck portion having a smaller diameter is formed between the rotation fixing holding portion and the bolt, and the rotation torque for rotating the nut Since the neck part is broken when the value of becomes a predetermined value or more, the completion of the tightening operation of the nut can be recognized.

  Furthermore, in the case of releasing the connection between the lower steel pipe pile and the upper steel pipe pile, the taper lock can be easily pulled out by separating the nut from the bolt since the taper lock is tapered. Therefore, the connection between the lower steel pipe pile and the upper steel pipe pile can be easily released.

  According to the present invention, a lock hole having a frusto-conical shape is formed in the connection portion of the lower steel pipe pile and the upper steel pipe pile, and the lower steel pipe pile and the upper die are formed by the frusto-conical taper lock attached to the lock hole. Since the steel pipe piles are connected and fixed, without increasing the diameter of the bolt, the rotational moment, compression force, and tension applied to the connecting portion of the lower steel pipe pile and the upper steel pipe pile by the taper lock having a diameter larger than that of the bolt. Sufficient holding power can be obtained against force, bending force and the like.

It is an explanatory view showing the connection method concerning the example of the present invention. The connection method which concerns on the Example of this invention is shown, (a) shows the state which mounted the taper lock unit, (b) shows the state which affirmed the taper lock unit. It is explanatory drawing which showed the connection method of the steel pipe pile based on the Example of this invention, (a) is a longitudinal direction sectional view, (b) is a horizontal direction sectional view. The state which removed the taper lock unit of this invention is shown, (a) is an attached state, (b) is explanatory drawing which showed the state which removed the taper lock.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The connection method according to the present invention will be described with reference to FIG. 1 and FIG. In this embodiment, the connection portion 5 is formed by the inside cylinder 1 fixed by welding to the upper end of the lower steel pipe pile and the outside cylinder 3 welded and fixed to the lower end of the upper steel pipe pile 2 in advance. Further, the lock hole 4 is provided through the connecting portion 5 formed of the inside cylinder 1 and the outside cylinder 3. The lock hole 4 has a small diameter opening 41 at its inner end and a large diameter opening 42 at its outer end, and its peripheral side surface 43 is tapered.

  Further, the taper lock unit 10 used in the present invention mounted in the lock hole 4 includes the taper lock 11 having a shape corresponding to the lock hole 4. The taper lock 11 has a small diameter front end 11 a having a diameter slightly larger than the diameter of the small diameter opening 41 and a large diameter rear end 11 b having a diameter slightly larger than the diameter of the large diameter opening 42. And an outer peripheral side surface 11c having a taper inclination angle substantially the same as the taper inclination angle of the peripheral side surface 43, and when attached to the lock hole 4, the state slightly protruding outside the lock hole 4 It is what is attached by. Further, a fixed washer 12 is disposed at the small diameter front end portion 11a of the taper lock 11, and a tightening washer 13 for fitting the fixed washer 12 inward to expand the fixed washer 12 in the radial direction, and the tightening washer It is comprised by the fastening means which consists of the bolt 14 and the nut 15 for fastening 13. The nut 15 is disposed at the large diameter rear end 11 b of the taper lock 11 via a washer 17. Further, a rotation fixing holding portion 16 for fixing the bolt 14 from the rotational moment is provided at the nut side end of the bolt 14.

  The fixed washer 12 has an annular shape, and a tapered surface having a predetermined angle is formed on the inner peripheral surface thereof. Further, a tapered surface having a predetermined angle is also formed on the outer peripheral surface of the tightening washer 13, and the outer peripheral surface of the tightening washer 13 is fitted along the inner peripheral surface of the fixed washer 12 to radially outside the fixed washer 12. It is intended to expand in the direction of

  The connection method of the present invention by the lock hole 4 of the above configuration and the taper lock unit 10 will be described below.

  First, at the connecting portion 5 between the inside cylinder 1 fixed by welding to the upper portion of the lower steel pipe pile and the outside cylinder 3 fixed by welding to the lower portion of the upper steel pipe pile 2 and externally fitted to the inside cylinder 1 A plurality of the radially extending lock holes 4 are formed equally in the circumferential direction of the connecting portion.

  The taper lock unit 10 is mounted in the lock hole 4 as shown in FIGS. 1 and 2A. After mounting the taper lock unit 10, the nut 15 is rotated with respect to the bolt 14 and tightened with a dedicated tool in a state of holding the rotary fixing holding portion 16 to fix the tightening washer 13 The taper lock unit 10 is fixed because the lock washer 12 is fitted into the washer 12 to push and spread the fixing washer 12 and to mesh with the peripheral edge of the small diameter opening 41. Further, finally, when the rotational torque of the nut 15 reaches a predetermined value or more, the rotational fixing holder 16 is broken at the neck thereof, and thus the tightening operation of the nut 15 is completed. It is.

  As a result, as shown in FIGS. 3A and 3B, the upper steel pipe pile 2 can be connected to the lower steel pipe pile 1. As a result, the rotational moment to which the upper steel pipe pile 2 is applied can be received by the taper lock 11 of the taper lock unit 10, so that it can be transmitted to the lower steel pipe pile 1.

  Further, the taper lock unit 10 can be separated from the connection portion. For example, as shown in FIG. 4 (a), the taper lock unit 10 fixed to the lock hole 4 releases the inside cylinder 1 and the out as shown in FIG. 4 (b) by disengaging the nut 15 from the bolt 14. Since the taper lock 11 holding between the side cylinder 3 can be easily released, both can be separated.

  The connection method of the present invention comprises an inner side plate defining not only the connection portions of the lower and upper steel pipe piles but also a so-called closed inner space, and an outer side plate disposed on the outer side of the inner side plate. As it can be used in the place where it is connected only by the work from, it is possible to easily perform its assembly and connection, and to easily dismantle what is required to be dismantled. It is possible.

DESCRIPTION OF SYMBOLS 1 inside cylinder 2 upper steel pipe pile 3 outside cylinder 4 lock hole 5 connection part 10 taper lock unit 11a small diameter front end 11b large diameter rear end 11c outer peripheral side 12 fixing washer 13 tightening washer 14 bolt 15 nut 16 rotation fixing holding portion 17 washer 41 small diameter opening 42 large diameter opening 43 surrounding side

Claims (2)

In order to connect the lower steel pipe pile and the upper steel pipe pile externally fitted to the lower steel pipe pile, the small diameter opening at the inner end and the outer side of the connection portion between the lower steel pipe pile and the upper steel pipe pile Forming a frusto-conical lock hole in communication with the end large diameter opening;
A tapered lock having a small diameter tip and a large diameter rear end corresponding to the lock hole and having a bolt through hole in the central axis direction, and a small diameter tip of the taper lock being in contact with the small diameter A fixed washer having an outer diameter substantially equal to the opening and capable of expanding, a tightening washer fitted to the fixed washer to expand the fixed washer, and disposed through the bolt through hole, A taper lock unit configured by a clamping unit configured to clamp a clamping washer so as to be fitted into the stationary washer, the locking hole from the large diameter opening side so that the stationary washer is positioned at the small diameter opening of the locking hole To be attached to the
The fixing washer bites into the periphery of the small diameter opening of the lock hole by inserting the tightening washer into the fixing washer and expanding the diameter of the fixing washer by the tightening means, and the taper lock unit is inserted into the lock hole method of connecting steel Kankui, characterized in that the fixing. The connection portion is characterized by comprising an inside cylinder welded and fixed to an upper portion of the lower steel pipe pile, and an outside cylinder welded and fixed to a lower portion of the upper steel pipe pile and externally fitted to the inner cylinder. The connection method according to claim 1, wherein

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