JP6144086B2 - Steel pipe pile joint structure - Google Patents

Description

  The present invention relates to a steel pipe pile joint structure for connecting a lower pile and an upper pile.

  Patent Document 1 (Japanese Patent Laid-Open No. 2001-64959) can be firmly gripped with a hydraulic machine or the like without damaging the upper end portion of the lower pile, and the lower end portion of the upper pile is screwed to the upper end portion of the lower pile. Providing steel pipe piles, lower piles and female threaded joint members that can easily attach female threaded joint members to the upper end of the lower pile main body pipe without damaging the lower pile head when connecting together The joint member attached to the upper end portion of the lower pile main body pipe fits inwardly of the upper end peripheral wall of the lower pile main body tube, and this cylindrical portion. It has an overhanging portion that is integrally connected to the upper end portion of the lower pile body and projects to the upper end surface side of the peripheral wall of the lower pile main body pipe, and is joined and integrated 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 the upper and lower piles are connected by field welding or a screw-type joint, and can reduce the mechanical burden on the bolt. Yes, the upper and lower piles can be firmly connected with a small number of bolts, and the joint between the lower and upper piles is prevented from overhanging outwards and smoothly penetrates into the ground. Steel piles with a structure that can be connected to the ends of the piles, connecting plates, and connecting the plates to the end plate or pile axis direction so that the plates are spaced with a predetermined size and spacing. Disclosed are joint members made of members having legs to be connected and bolted to upper and lower piles using these joint members.

  Patent Document 3 (Japanese Patent Application Laid-Open No. 2003-105755) is capable of easily connecting different diameter steel pipe piles with threaded joint members to shorten the construction time, without requiring advanced welding technology, and without being influenced by the weather. An upper screw provided at the upper end of the lower steel pipe pile that can be constructed and provides a joint structure between different diameter steel pipe piles that can exhibit stable joint performance that can transmit stress 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 joint member, and the lower steel pipe pile and the upper screw joint member are fitted in the fitting portion with the upper end portion of the lower steel pipe pile inserted. Is disclosed, and a joint structure is disclosed in which a male screw of a lower screw joint member provided at a lower end portion of an upper steel pipe pile is screwed and fastened to a female screw of an upper screw joint member.

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

JP 2001-64959 A JP 2001-64962 A JP 2003-105755 A JP 2008-25156 A

  When building on soft ground, pile foundations are generally used to support the building. In this case, since it is required to dig deeply, the lower steel pipe pile (lower pile) with a cutting blade, excavation claw, and spiral blade attached to the tip is rotated and propelled by a rotary drive device and installed on the ground. Furthermore, an upper steel pipe pile (upper pile) is connected to the upper part of this lower pile, and it is further rotated and propelled to install deeply in the ground.

  Steel pipe piles have a role to support the load of the superstructure over a long period of time and resist the load (horizontal force) applied to the steel pipe pile from the side in a portion near the ground that occurs in a relatively short time such as an earthquake. Have a role to play. Since this horizontal force becomes larger and deeper as it is closer to the ground surface, it is not necessary to form the entire steel pipe pile with the same cross-sectional area. For this reason, the structure close to the ground surface has a large projected area, and the part that receives vertical load only has to withstand compression and buckling. 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 corresponding to this and a smaller-diameter pile material. 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, or the different diameter steel pipe pile and the upper pile in the field, There is a problem that it is difficult to weld with good quality in strong winds. Especially when welding different diameter steel pipe piles to the lower pile, and when welding upper piles to the upper end of the diameter steel pipe piles, it is necessary to hold the different diameter steel pipe piles or upper piles that are positioned above during welding However, there is a problem that accuracy control in the vertical direction (verticality) is difficult.

  From the above, the present invention is not limited to steel pipe piles of different diameters or the same type, and can improve the verticality at the time of joining and can easily perform joining work (welding or bolt crimping). It is to provide a joint structure.

  Therefore, the steel pipe pile joint structure according to the present invention is a steel pipe pile joint structure for connecting the lower steel pipe pile first installed on the ground and the upper steel pipe pile connected to the upper end of the lower steel pipe pile. A cylindrical lower pile special portion integrally joined to the upper end of the lower steel pipe pile and having the same outer diameter as the lower steel pipe pile, An outer fitting portion having an inner diameter substantially equal to the outer diameter of the lower pile special portion, and an upper end fixing portion having an inner diameter substantially equal to the outer diameter of the lower end portion of the upper steel pipe pile in order to externally fit to the lower end portion of the upper steel pipe pile The lower pile of the upper pile special part and the outer peripheral part of the lower pile special part that are externally fitted to the lower pile special part are fixed by a fixing means. .

  The fixing means is preferably welding.

  With this, for example, a cutting blade, excavation claw, and spiral claw are attached to the tip, and the lower pile special provided at the upper end of the lower steel pipe pile that is rotationally propelled and installed in the ground by a rotary drive device The upper steel pipe pile can be easily mounted and fixed to the lower steel pipe pile by fitting the upper pile special part on the upper part to the outer part and welding and fixing the lower edge periphery to the outer peripheral surface of the lower pile special part. It is. In this case, the lower steel pipe pile and the lower pile special part, and the upper steel pipe pile and the upper pile special part can be welded and fixed at the factory, and when attaching the upper steel pipe pile to the lower steel pipe pile, Since the upper pile special portion is externally fitted to the lower pile special portion, the verticality can be maintained, so that welding (fixing) at the site is facilitated.

  Furthermore, the fixing means includes a first through-hole penetrating the lower pile special portion in the radial direction, and a nut portion welded and fixed to an inner peripheral surface of the lower pile special portion corresponding to the first through-hole. The second through-hole penetrating to the position corresponding to the first through-hole of the lower pile special portion and the first through-hole and the second through-hole are penetrated when the upper steel pipe pile is mounted. It is desirable to be constituted by bolts arranged.

  Thereby, an upper steel pipe pile and a lower steel pipe pile can fix the upper pile special part of an upper steel pipe pile, and the lower pile special part of a lower steel pipe pile by bolt crimping | compression-bonding. In the case of bolt crimping, workability is improved because no special technique is required unlike welding.

  Moreover, the truncated cone-shaped 1st through-hole which penetrates the said lower pile special part to radial direction, and the truncated cone-shaped 2nd through-hole which penetrates the said upper pile special part corresponding to this 1st through-hole When the upper pile special part is mounted on the lower pile special part, the lower pile special part and the upper pile special part are penetrated by the first through hole and the second through hole. The inside of the pile special part and the upper pile special part is formed with a continuous truncated cone-shaped mounting hole having a small diameter and the outside having a large diameter, and the fixing means has an inner small diameter corresponding to the truncated cone-shaped mounting hole. A top portion having a truncated cone shape having a portion and an outer large-diameter portion, having a through hole in the axial direction and an annular peripheral wall having a tapered inclined surface defining a concave mounting recess in the inner small-diameter portion; A head that fits into a mounting recess in the peripheral wall and deforms the peripheral wall outward; A fixing bolt constituted by a rod having a male thread cut through the through-hole of the screw and a rotation holding portion for fixing the rod, and the fixing bolt screwed into the fixing bolt and rotated. It is desirable that the head is constituted by a nut that allows the head to be inserted into the mounting recess.

  As a result, when the upper pile special part is attached to the lower pile special part, a frustoconical attachment hole is formed by the first and second through holes of the lower pile special part and the upper pile special part, and fixed to this. Insert the top part with the bolt and nut attached, fix the rotation holding part and rotate the nut, and the head of the fixing bolt goes into the mounting recess of the top part. Since the surrounding wall is spread outward by the penetration of the head, the frame portion of the fixing means can be fixed to the mounting hole. In addition, this allows the lower pile special part and the upper pile special part to be fixed firmly and strongly with the top part having a diameter larger than that of the bolt. is there.

  It is desirable that the lower pile special portion is formed thicker than the lower steel pipe pile.

  Thereby, a deformation | transformation of a lower pile special part can be prevented with respect to the rotational force for twisting and propelling a lower steel pipe pile.

  As described above, according to the present invention, the upper pile special portion formed at the lower end of the upper steel pipe pile is externally or internally fitted and fixed to the lower pile special portion formed at the upper end of the lower steel pipe pile. As a result, it is possible to improve the verticality at the time of joining, because it is a built-in type, it is possible to prevent the upper steel pipe pile from overturning, and because it has a double pipe structure, the strength can be increased, the upper pile Since the special part and the lower pile special part can be joined to the upper steel pipe pile and the lower steel pipe pile by welding at the factory, respectively, it is possible to achieve effects such as being able to be securely fixed by welding.

  In addition, when the upper pile special part is attached to the lower pile special part, a mounting hole having a truncated cone shape is formed, and the truncated cone shaped frame part of the fixing means is inserted into the attachment hole to form the lower pile special part. Since the upper pile special part is fixed, it can be fixed by a piece with a larger diameter than the bolt without increasing the diameter of the bolt, so the fixing force between the lower pile special part and the upper pile special part is improved. It is something that can be done.

It is explanatory drawing of the steel pipe pile joint structure which concerns on Example 1 of this invention, (a) is the partial front view, (b) is sectional drawing. It is sectional drawing of the upper pile special part of the steel pipe pile joint structure which concerns on Example 1 of this invention. It is sectional drawing of the lower pile special part of the steel pipe pile joint structure which concerns on Example 1 of this invention. It is sectional drawing of the steel pipe pile joint structure which concerns on Example 2 of this invention. (A) is sectional drawing of the upper pile special part of the steel pipe pile joint structure which concerns on Example 2 of this invention, (b) is a cross section of the lower pile special part of the steel pipe pile joint structure which concerns on Example 1 of this invention. FIG. (A) is a front view of the steel pipe pile joint structure which concerns on Example 3 of this invention, (b) is sectional drawing of the steel pipe pile joint structure which concerns on Example 3 of this invention. It is sectional drawing of the steel pipe pile joint structure which concerns on Example 4 of this invention. (A) is sectional drawing of the upper pile special part of the steel pipe pile joint structure which concerns on Example 4 of this invention, (b) is the bottom pile special part of the steel pipe pile joint structure which concerns on Example 4 of this invention. It is sectional drawing. (A) is side sectional drawing of the steel pipe pile joint structure which concerns on Example 5 of this invention, (b) is a plane sectional view of the steel pipe pile joint structure which concerns on Example 5 of this invention. These are explanatory drawings which showed the mounting state of the steel pipe pile joint structure which concerns on Example 5 of this invention. It is explanatory drawing of the fixing means of the steel pipe pile joint structure which concerns on Example 5 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  The steel pipe pile joint structure 1 which concerns on Example 1 of this invention is for welding and fixing the upper steel pipe pile 4 to the lower steel pipe pile 2, as shown in FIG. In the first embodiment, the upper steel pipe pile 4 has a large-diameter portion 41 having a large upper cross-sectional area so as to have a large cross-sectional area in the ground surface portion, and a reduced-diameter portion that has been reduced in diameter to join the lower steel pipe pile 2 The upper pile special portion 5 is provided at the lower end portion 43 of the reduced diameter portion 42.

  As shown in FIG. 2, the upper pile special portion 5 has an upper end fixing portion 53 fitted on the lower end portion 43 of the reduced diameter portion 42 of the upper steel pipe pile 4 and an outer fit on the lower steel pipe pile 2. It is comprised by the external fitting part 52 for performing, and is fixed to the said upper steel pipe pile 4 with the welding 7. FIG. The fixing work by the welding 7 is performed in a factory. This simplifies on-site work. Moreover, the internal diameter of this upper pile special part 5 is a thing substantially equal to the outer diameter of the lower steel pipe pile 2 mentioned below.

  For example, a cutting blade, an excavation claw, a spiral blade or the like is attached to the lower end (not shown) of the lower steel pipe pile 2, and the lower steel pipe pile 2 is installed on the ground by being twisted and propelled by a rotary drive device or the like. Is.

  After the lower steel pipe pile 2 is installed, the upper steel pipe pile 4 can be placed on the lower steel pipe pile 2 so that the upper pile special portion 5 of the upper steel pipe pile 4 is fitted on the upper end of the lower steel pipe pile 2. Furthermore, since the lower end portion 43 of the upper steel pipe pile 4 and the upper end portion 21 of the lower steel pipe pile 2 can be brought into contact with each other, the verticality of the lower steel pipe pile 2 and the upper steel pipe pile 4 can be easily obtained. It is. Moreover, since the lower steel pipe pile 2 is inserted in the upper pile special part 5, since the upper steel pipe pile 4 can be hold | maintained easily, the outer periphery of the lower end peripheral part 51 of the upper pile special part 5, and the lower steel pipe pile 2 It is possible to easily perform welding 8 as a fixing means between the surface 22 and the surface 22.

  The steel pipe pile joint structure 1A according to the second embodiment of the present invention shown in FIGS. 4 and 5 is characterized in that the fixing means is not by welding but by bolt crimping. Note that, in the following embodiments, the same configurations and the portions having the same effects are denoted by the same reference numerals, and description thereof is omitted.

  Moreover, in the steel pipe pile joint structure 1A which concerns on Example 2 of this invention, as shown in FIG.5 (b), since it pressure-bolts, the lower pile special part formed thicker than the lower steel pipe pile 2 3 is provided at the upper part of the lower steel pipe pile 2 and fixed at the factory by welding 6. As a result, the strength of the bolt crimping portion can be improved.

  The inner peripheral surface of the lower pile special portion 3 includes a first through hole 32 that penetrates the lower pile special portion 3 in the radial direction, and an inner circumference of the lower pile special portion 3 that corresponds to the first through hole 32. A nut portion 33 fixed to the surface 37 by a weld 34 is formed, and the upper pile special portion 5 has a second penetrating to a position corresponding to the first through hole 32 of the lower pile special portion 3. Through holes 54 are formed, and when the upper steel pipe pile 4 is mounted, bolts 35 are mounted through the first through holes 32 and the second through holes 54, and the bolts 35 are screwed into the nut portions 33. Thus, the upper steel pipe pile 4 can be mounted and fixed to the lower steel pipe pile 2.

  In this case, since the lower pile special portion 3 and the upper pile special portion 5 are bolted, frictional resistance between the outer peripheral surface 31 of the lower pile special portion 3 and the inner peripheral surface 55 of the upper pile special portion 5 is generated. The joining force between the lower steel pipe pile 2 and the upper steel pipe pile 4 can be improved.

  As shown in FIG. 6, the steel pipe pile joint structure 1B according to Example 3 of the present invention has the same configuration as the steel pipe pile joint structure 1A according to Example 2, but the upper steel pipe pile structure 4A has a uniform cross-sectional area. Is different in that it has a cylindrical shape with the same diameter. Also in this case, since the upper pile special part 5 can be welded and carried into the upper steel pipe pile 4A at the factory, the shape of the upper steel pipe piles 4 and 4A can be changed flexibly according to the work process. is there.

  In Examples 2 and 3, although fixed by bolt crimping, after fixing by bolt crimping, the gap between the lower peripheral edge 51 of the upper pile special part 5 and the outer peripheral surface of the lower pile special part 3 is further increased. It may be made to weld.

  As shown in FIGS. 7 and 8, the steel pipe pile joint structure 1C according to the fourth embodiment of the present invention has an outer surface that is substantially equal to the inner diameter of the lower steel pipe pile 2 in order to fit into the lower steel pipe pile 2. An upper portion having an inner fitting portion 5 having a diameter and an upper end fixing portion 53 having an outer diameter substantially equal to the inner diameter of the lower end portion 43 of the upper steel pipe pile in order to be fitted into the lower end portion 43 of the upper steel pipe pile 4. A pile special portion 5A is provided.

  Thus, as shown in FIG.7 and FIG.8, the steel pipe pile joint structure 1B which concerns on Example 4 of this invention is the top with respect to the steel pipe pile joint structure 1 of Example 1 shown by FIG. The pile special portion 5 </ b> A is not fitted to the reduced diameter portion 42 of the upper steel pipe pile 4 but is fitted inside. In this case, as shown in FIG. 8A, the upper pile special portion 5A and the reduced diameter portion 42 are transported to the site with the welded portion 11 applied at the factory, and the upper pile special portion 5A is lowered at the site. Inserted into the side steel pipe pile 2, the upper end portion 21 of the lower steel pipe pile 2 and the lower end portion 43 of the reduced diameter portion 42 are brought into contact with each other, and welding 10 is further performed here to fix both. .

  As described above, according to the present invention, the upper pile special portions 5 and 5A are fixed to the lower ends of the upper steel pipe piles 4 and 4A by external fitting or internal fitting by factory welding, and the lower steel pipe pile 2 or Since the lower pile special part 3 extended and fixed to the upper end of the lower steel pipe pile by factory welding can be internally or externally fitted to the upper pile special part 5 and fixed by welding or bolt crimping, In addition to improving the properties, the double-pipe structure can increase the strength at the joint.

  A steel pipe pile joint structure 1D according to Example 5 of the present invention is a modification of the steel pipe pile joint structure 1A according to Example 2 described above. Conventionally, the bolt diameter used in the steel pipe pile joint structure must be thickened according to the load applied to the steel pipe pile joint structure, but the number of bolt diameters is limited, so increase the number. However, there is an upper limit to increasing the number.

  Therefore, the steel pipe pile joint 1D according to the fifth embodiment of the present invention is characterized in that a special fixing mechanism 100 is provided as a fixing means, as shown in FIGS. 9A and 9B, for example. To do. In this Example 5, in order to fix between the lower pile special part 3 and the upper pile special part 5, the four fixing mechanisms 100 arrange | positioned every 90 degree | times are provided.

  In order to arrange the fixing mechanism 100, in the steel pipe pile joint structure 1D according to the fifth embodiment, as shown in FIG. 10, the first through hole 34A penetrating the lower pile special portion 3 in the radial direction is provided. A frustoconical shape that is formed in a truncated cone shape and that has a second through hole 54A that passes through the upper pile special portion 5 corresponding to the first through hole 34A and that is continuous with the first through hole 34A. When the upper pile special part 5 is attached to the lower pile special part 3, the lower pile special part 3 and the upper pile special part are formed by the first through hole 34A and the second through hole 54A. A continuous frustoconical mounting hole 90 having a small diameter on the inside and a large diameter on the outside of the lower pile special portion 3 and the upper pile special portion 5 is formed.

  As shown in FIG. 11, the fixing mechanism 100 includes a frame portion 101 having a truncated cone shape having an inner small diameter portion 101a and an outer large diameter portion 101b corresponding to the frustoconical mounting hole 90, and a frame portion 101. The fixing bolt 102 is fixed to the fixing bolt 102, the nut 103 is screwed onto the fixing bolt 102, and the washer 104 is disposed between the nut 103 and the top part 101.

  The top part 101 has a through hole 101c through which the rod 102b of the fixing bolt 102 passes in the axial direction, and the inner small diameter part 101a has a tapered inclined surface 101e defining a concave mounting recess 101d on the inner side. An annular peripheral wall 101f is provided.

  The fixing bolt 102 has a head 102a that fits into the mounting recess 101d in the peripheral wall 101f and deforms the peripheral wall 101f outward, and a male screw that is inserted through the through hole 101c of the top part 101. Rod 102b and a rotation holding portion 102c for fixing the rod 102b. The rotation holding portion 102c can be removed after the work is finished.

  With the above configuration, the upper pile special portion 5 is attached to the lower pile special portion 3, and the positions of the first through hole 34A of the lower pile special portion 3 and the second through hole 54A of the upper pile special portion 5 are aligned. In this way, a frustoconical mounting hole 90 is formed. In the fifth embodiment, four mounting holes 90 are formed. In order to fix the lower pile special portion 3 and the upper pile special portion 5, the top portion 101 is attached to the attachment hole 90 in the attachment hole 90. At this time, since the mounting hole 90 and the top part 101 are formed in a truncated cone shape having a small front end and a large rear end, there is an advantage that the mounting of the fixing mechanism 100 is easy.

  After mounting the fixing mechanism 100, by holding the rotation holding portion 102c and tightening the nut 103, the head 102a of the fixing bolt 102 enters the mounting recess 101d of the top portion 101 along the tapered inclined surface 101e. Therefore, the peripheral wall 101f is deformed outward. As a result, the fixing mechanism 100 is firmly fixed to the mounting hole 90, so that the lower pile special portion 3 and the upper pile special portion 5 can be firmly fixed. Moreover, since both are fixed by the top part 101 larger than a bolt diameter, the load concerning a connection part can fully be received.

  As described above, the steel pipe pile joint structure 1D according to the fifth embodiment of the present invention has an effect that the fixing mechanism 100 can be easily mounted and sufficient strength can be imparted to the joint portion.

1, 1B, 1C, 1D Steel pipe pile joint structure 2 Lower steel pipe pile 3 Lower pile special part 4, 4A Upper steel pipe pile 5, 5A Upper pile special part 6, 7, 8 Welding 32, 32A First through hole 33 Nut Part 34 Welding 35 Bolt 43 Lower end part 52 Outer fitting part 53 Upper end fixing part 54, 54A Second through hole 90 Mounting hole 100 Fixing mechanism 101 Frame part 102 Fixing bolt 103 Nut

Claims (2)

A steel pipe pile joint structure for connecting a lower steel pipe pile first installed on the ground and an upper steel pipe pile connected to the upper end of the lower steel pipe pile, and is integrated with the upper end of the lower steel pipe pile. And a cylindrical lower pile special portion having the same outer diameter as the lower steel pipe pile, and an inner diameter substantially equal to the outer diameter of the lower pile special portion for external fitting to the lower pile special portion The upper pile special portion comprising an outer fitting portion and an upper end fixing portion having an inner diameter substantially equal to the outer diameter of the lower end portion of the upper steel pipe pile in order to fit to the lower end portion of the upper steel pipe pile, In the steel pipe pile joint structure in which the lower end portion of the upper pile special portion and the outer peripheral portion of the lower pile special portion that are externally fitted to the lower pile special portion are fixed by fixing means ,
Constructed by a frustum-shaped first through hole penetrating the lower pile special portion in the radial direction and a frustum-shaped second through hole penetrating the upper pile special portion corresponding to the first through hole When the upper pile special part is mounted on the lower pile special part, the lower pile special part penetrates the lower pile special part and the upper pile special part by the first through hole and the second through hole. Forming a continuous frustoconical mounting hole having a small diameter on the inside and a large diameter on the inside of the upper pile special part,
The fixing means has a truncated cone shape having an inner small diameter portion and an outer large diameter portion corresponding to the frustoconical mounting hole, has a through hole in the axial direction, and has a concave mounting recess in the inner small diameter portion. A top part having an annular peripheral wall having a tapered slope on the inside, a head that fits into a mounting recess in the peripheral wall and deforms the peripheral wall to the outside, and a male inserted through the through hole of the top part A fixing bolt composed of a threaded rod and a rotation holding part for fixing the rod, and a screw that is screwed into the fixing bolt and rotated to fit the head of the fixing bolt into the mounting recess. A steel pipe pile joint structure characterized by comprising a nut to be inserted. The steel pipe pile joint structure according to claim 1, wherein the lower pile special portion is formed to be thicker than the lower steel pipe pile.

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