JP2006207117A - Joining structure of steel pipe pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining structure of a steel pipe pile requiring no welding at site, having excellent reliability, construction efficiency, and workability, requiring less number of parts forming a joined part, and enabling the easy machining of a joint part. <P>SOLUTION: The end part 11 of a first steel pipe pile 1 comprises a plurality of projected parts 11a formed apart from each other in the circumferential direction so as to be projected in its axial direction. The end part 12 of a second steel pipe pile 2 is formed in a roughly complementary shape to the shape of the end part of the first steel pipe pile. A hole of a prescribed shape is formed between the projected parts 11a and 11b of the first and second steel pipe piles adjacent to each other when the end parts of these piles are fitted to each other, and the first steel pipe pile is connected to the second steel pipe pile through a pin member 13 inserted into the hole. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a joining structure of steel pipe piles.

  Currently, the welded joint structure that joins a pair of steel pipe piles by on-site welding occupies most of the steel pipe pile joint structures. In addition, as a non-welded joint structure that does not use on-site welding, a screw-type joint structure, a joint structure that covers and tightens the flange end plate from the outside, etc. have been proposed, but it is rarely used in practice. Is the actual situation. In general, in the case of a steel pipe pile joint structure by field welding, the field welding for joining a pair of steel pipe piles requires several tens of hours, the workability is poor, and the reliability is low. In addition, the welding work is low in workability because it dislikes water and cannot work in rainy weather.

  Also, in recent years, steel pipe piles (called “Tsubasa piles”, etc.) that have a form in which the tip is spread like a screw and can obtain a large support force have been developed and are becoming popular. . The construction method of this type of steel pipe pile is different from the general method of steel pipe pile construction, that is, the Nakabori method using auger, and the screw-like blade at the tip is screwed into the ground by applying a rotational force to the pile (screwing). It is a construction method. Therefore, in this kind of steel pipe pile, it is also possible to pull out the pile once sunk into the ground by applying a reverse rotational force to the pile.

  Based on this technical background, there is a demand for a non-welded joint structure that can be applied to all types of steel pipe piles, including steel pipe piles that have a screw-like shape with blades spread out, and that does not require on-site welding. It was. Therefore, the present applicant has proposed a steel pipe pile joint structure excellent in reliability, workability and workability without requiring on-site welding (see, for example, Patent Document 1).

JP 2004-52333 A

  In the conventional joint structure of steel pipe piles disclosed in Patent Document 1, a joint portion having a relatively complicated shape is attached to the end portion of the steel pipe pile by factory welding, and a plurality of arc-shaped band members and a plurality of fastening members ( Bolts and nuts) are used to connect the joints on site. As a result, in the conventional joint structure of Patent Document 1, the number of members (number of types) constituting the joint portion is relatively large, and the processing of the joint portion is relatively complicated.

  The present invention has been made in view of the above-described problems, and is excellent in reliability, workability, and workability without requiring on-site welding, and has a small number of members constituting the joint portion and the joint portion. It aims at providing the joining structure of the steel pipe pile which is easy to process.

In order to solve the above problems, in the first invention of the present invention, in the structure for joining a pair of steel pipe piles,
The end of the first steel pipe pile has a plurality of convex portions formed at intervals in the circumferential direction so as to protrude in the axial direction thereof,
The end of the second steel pipe pile has a shape substantially complementary to the shape of the end of the first steel pipe pile,
A hole having a predetermined shape is formed between the convex portions adjacent to each other in the fitted state between the end portion of the first steel pipe pile and the end portion of the second steel pipe pile, and a pin member inserted into the hole is interposed therebetween. The first steel pipe pile and the second steel pipe pile are connected to each other.

  According to a preferred aspect of the first invention, a plurality of holes are formed between the convex portions adjacent to each other at intervals in the axial direction. Moreover, it is preferable that the said hole is a circular through-hole extended in a radial direction. In this case, it is preferable that a boundary surface formed between the convex portions adjacent to each other substantially coincides with a plane extending in the axial direction including the central axis of the circular through hole.

  Moreover, according to the preferable aspect of 1st invention, it is preferable to provide the prevention means for preventing that the said pin member falls out of the said hole. In this case, it is preferable that the prevention means has a backing member attached to the inside of the end portion of the first steel pipe pile so as to cover at least a part of the hole. Alternatively, the prevention means is provided on the pin member so as to engage with at least one of an end portion of the first steel pipe pile and an end portion of the second steel pipe pile when the pin member is inserted into the hole. It is preferable to have the engaging member.

  Moreover, according to the preferable aspect of 1st invention, the 1st joint part in which these convex parts were formed was attached to the edge part of the said 1st steel pipe pile by factory welding, and the edge of the said 2nd steel pipe pile It is preferable that the 2nd joint part in which the said some convex part was formed is attached to the part by factory welding. In this case, it is preferable that the first joint portion and the second joint portion have the same shape.

  In the 2nd form of this invention, it is a manufacturing method of the said 1st joint part of a 1st form, and the said 2nd joint part, Comprising: The space | interval is spaced apart in the circumferential direction with respect to the steel pipe for joints which has predetermined | prescribed length. A hole forming step for forming a plurality of holes of the predetermined shape, and the joint steel pipe formed with the plurality of holes in an uneven shape corresponding to a boundary line between the first joint portion and the second joint portion. The manufacturing method characterized by including the cutting process cut | disconnected. In this case, it is preferable to further include a step of cutting the steel pipe to the predetermined length prior to the hole forming step.

  The present invention realizes a steel pipe pile joint structure that is excellent in reliability, workability, and workability without requiring on-site welding, and that has a small number of members constituting the joint part and is easy to process the joint part. be able to. Since the joining structure of steel pipe piles according to the present invention has a configuration capable of sufficiently ensuring the required mechanical performance, all steel pipes including steel pipe piles of a type having a form in which the tip is spread like a blade in a screw shape. Applicable to piles.

  Embodiments of the present invention will be described with reference to the accompanying drawings. Drawing 1 is a figure showing the joining structure of the steel pipe pile concerning the embodiment of the present invention, and is a perspective view showing roughly the composition of the joint part attached to the end of the steel pipe pile. FIG. 2 is a perspective view schematically showing a joined state in which the pin member is attached in a state where the ends of the pair of steel pipe piles shown in FIG. 1 are fitted to each other. 3A and 3B are diagrams for explaining the mounting state of the pin member in FIG. 2, wherein FIG. 3A is a developed side view, and FIG. 3B is a cross-sectional view taken along line AA in FIG. ing.

  In addition, in FIG. 1, since the edge part structure of each steel pipe pile is fundamentally the same, about the part concerning a 2nd steel pipe pile, the reference sign is shown in the parenthesis. Referring to FIG. 1, a pair of steel pipe piles to be joined to each other, that is, the first steel pipe pile 1 and the second steel pipe pile 2, a first joint part 11 and a second joint part 12 are, for example, factory welded ( The welds are respectively attached by reference numerals 21 and 22, respectively.

  The first joint part 11 and the second joint part 12 are both a plurality of convex parts 11a formed at equal intervals in the circumferential direction so as to protrude in the axial direction of the first steel pipe pile 1 and the second steel pipe pile 2. 12a and a plurality of recesses 11b and 12b formed therebetween, respectively. Here, each convex part 11a formed in the 1st joint part 11 and each convex part 12a formed in the 2nd joint part 12 are mutually the same shape, ie, along two sides and the circumferential direction along an axial direction. And has a generally rectangular shape as defined by the two sides.

  Moreover, the 1st joint part 11 and 2nd so that the convex part 11a and recessed part 11b formed in the 1st joint part 11 and the recessed part 12b and convex part 12a formed in the 2nd joint part 12 may mutually fit. The joint portion 12 has a substantially complementary shape. More specifically, the first joint portion 11 and the second joint portion 12 have the same shape. Moreover, in each convex part 11a of the 1st joint part 11, and each convex part 12a of the 2nd joint part 12, it is a semicircle notch part in the position corresponding to the approximate center of the side along the axial direction of a steel pipe. 11c and 12c are formed, respectively.

  These notches 11c and 12c constitute a circular through-hole for accommodating the pin member 13 in the fitted state between the first joint part 11 and the second joint part 12, as will be described later. Become. In this way, the first joint portion 11 and the second joint portion 12 are opposed to each other so that the convex portion 11a and the concave portion 12b of the second joint portion 12 face each other, and the concave portion 11b of the first joint portion 11 and the convex portion 12a of the second joint portion 12 face each other. By positioning the first steel pipe pile 1 and the second steel pipe pile 2 and bringing the first steel pipe pile 1 and the second steel pipe pile 2 relatively close to each other, a fitting state as shown in FIGS. 2 and 3 is obtained. It is done.

  At this time, the front end surface of the convex portion 11a of the first joint portion 11 and the base surface of the concave portion 12b of the second joint portion 12 are in close proximity to each other, and the front end surface of the convex portion 12a of the second joint portion 12 and the first joint portion. 11 is close to the base surface of the recess 11b. Further, the side surface of the convex portion 11a of the first joint portion 11 and the side surface of the convex portion 12a of the second joint portion 12 are close to each other. In the present embodiment, the tip surfaces of the convex portions 11a and 12a and the basal surfaces of the concave portions 12b and 11b, and the side surfaces of the convex portions 11a and the side surfaces of the convex portions 12a are not in contact with a slight gap. Will be described later in connection with the method of manufacturing the first joint portion 11 and the second joint portion 12.

  In the fitting state of the first joint part 11 and the second joint part 12, a circular through-hole is formed by the notches 11c and 12c between the adjacent convex parts 11a and 12a. These circular through holes extend, for example, in the radial direction. Further, the boundary surface formed between the convex portions 11a and 12a adjacent to each other substantially coincides with a plane extending in the axial direction including the central axis of the circular through hole. In the joint structure of the present embodiment, by inserting the pin member 13 as a shear key into each circular through hole, the first joint portion 11 and the second joint portion 12 are connected via the pin member 13. As a result, the 1st steel pipe pile 1 and the 2nd steel pipe pile 2 are connected (joined).

  In manufacturing the first joint portion 11 and the second joint portion 12, for example, a steel pipe that is substantially thicker than the first steel pipe pile 1 and the second steel pipe pile 2 is dimensioned in a predetermined length (see FIG. 3A). A steel pipe for a joint is prepared by cutting it into L1). However, it is also possible to prepare a steel pipe for joints by using an appropriate forming technique or the like without cutting the thick steel pipe. Next, a plurality of circular through holes spaced apart in the circumferential direction are formed in the steel pipe for joint using a drilling means such as a drill.

  Here, the difference between the diameter of the circular through hole and the diameter of the pin member 13 to be inserted is set to a necessary minimum size (for example, 0.5 mm to 1 mm), and the circular shape having a diameter of a desired dimension is set. It is easy to sequentially form the through holes with high accuracy. Finally, the joint steel pipe in which a plurality of circular through-holes are formed is automatically cut into irregularities corresponding to the boundary line between the first joint part 11 and the second joint part 12 using, for example, gas or laser. .

  In this case, a gap of, for example, 2 mm to 3 mm is generated between the first joint portion 11 and the second joint portion 12 in a connected state via the pin member 13 by gas cutting or laser cutting. However, as will be described later, since the force transmission at the joint portion is performed only by the pin member 13 inserted into the circular through hole, there is a gap between the first joint portion 11 and the second joint portion 12. There is no problem. Thus, in this embodiment, the shape of the 1st coupling part 11 and the 2nd coupling part 12 is comparatively simple, The manufacture is also comparatively easy.

  In general, the mechanical performance required in the joint structure of steel pipe piles is compression strength, tensile strength, shear strength, bending moment strength, and rotational torsion strength. In this embodiment, only the pin member 13 inserted into the circular through-hole, that is, the contact between the outer peripheral surface of the pin member 13 and the inner peripheral surface of the notches 11c and 12c formed in the convex portions 11a and 12a. By contact, desired compression strength, desired tensile strength, desired shear strength, desired bending moment strength, and desired rotational torsion strength can be ensured.

  Thus, in this embodiment, the steel pipe pile joint structure is excellent in reliability, workability, and workability without requiring on-site welding, and has a small number of members constituting the joint and easy processing of the joint. Can be realized. As described above, the steel pipe pile joint structure of the present embodiment can sufficiently ensure the required mechanical performance (compression strength, tensile strength, shear strength, bending moment strength, rotational torsion strength). Therefore, the present invention can be applied to all types of steel pipe piles including a steel pipe pile of a type in which the tip has a form in which blades are spread like a screw.

  In particular, in the joint structure of the present embodiment, unlike other joint structures according to the prior art, force is transmitted in a form without eccentricity in the radial direction of the steel pipe, so the additional bending moment in the out-of-plane direction of the steel pipe There is an advantage that substantially does not occur. This point is very advantageous when joining steel pipe piles having a relatively large diameter, that is, large-diameter steel pipe piles.

  Further, in the joint structure of this embodiment, only a relatively high accuracy is required only for the clearance between the circular through hole and the pin member 13, and the accuracy required for other portions is low. There is. In addition, if the above-described manufacturing method relating to the joint portions (11, 12) is employed, it is easy to accurately form a circular through hole having a desired diameter in the pin member 13.

  By the way, in the joint structure of this embodiment, the force along the radial direction of the steel pipe does not act on the pin member 13 when transmitting the force, but the pin member 13 is prevented from falling off from the through hole during construction. It is preferable to provide a prevention means. As a preventing means, as shown in FIG. 4 (a), the first joint portion 11 and / or the second joint portion 12 so as to cover the through hole (in principle, cover at least a part of the through hole). A backing member 31 attached to the inside can be used.

  In this case, for example, after inserting the pin member 13a having a cylindrical shape into the through hole, the first joint portion 11 and / or so as to cover the through hole (in principle, cover at least a part of the through hole). Alternatively, the cover member 32 is attached to the outside of the second joint portion 12. For example, the backing member 31 can be attached by factory welding (the welded portion is indicated by reference numeral 31a), and the cover member 32 can be attached on the spot by, for example, a set bolt (not shown). The pin member 13a having a cylindrical shape is obtained by cutting a steel rod having a circular cross section into a predetermined length, for example.

  Alternatively, as a prevention means, as shown in FIG. 4B, a bolt-shaped pin member 13b having an engagement member 13ba built in the tip can also be used. In this case, when the pin member 13b is inserted into the through-hole, the engaging member 13ba biased by the action of a spring or the like protrudes outward from the cylindrical main body portion of the pin member 13b and the first joint portion 11 and / or the first joint member 13b. While engaging with the two joint portions 12, the head portion 13bb of the pin member 13b substantially abuts against the first joint portion 11 and / or the second joint portion 12.

  In the above-mentioned embodiment, although the 1st joint part 11 and the 2nd joint part 12 have the same shape mutually, it is not limited to this but about the shape of the 1st joint part 11 and the 2nd joint part 12 Various modifications are possible.

  Moreover, in the above-mentioned embodiment, although each convex part 11a formed in the 1st joint part 11 and each convex part 12a formed in the 2nd joint part 12 have a rectangular form as a whole, it is limited to this. Without limitation, various modifications can be made to the form of the convex portions 11a and 12a.

  Moreover, in the above-mentioned embodiment, a steel pipe pile (1,2) and a joint part (11,12) so that the outer surface of a steel pipe pile (1,2) and the outer surface of a joint part (11,12) may correspond substantially. ) And welding. However, without being limited thereto, for example, when the auger Nakabori method is used, the inner surface of the steel pipe pile (1, 2) and the joint portion (11, 12) of the steel pipe pile (1, 2) as shown by the broken line in FIG. The steel pipe piles (1, 2) and the joints (11, 12) can be welded so that the inner side faces substantially coincide. Generally, various modifications are possible for the welding position of the steel pipe pile (1, 2) with respect to the joint portion (11, 12).

  In the above-described embodiment, one circular through hole is formed between the convex portions 11a and 12a adjacent to each other in the fitted state of the first joint portion 11 and the second joint portion 12. Without being limited thereto, various modifications are possible with respect to the shape, form, number, etc. of the holes formed between the convex portions 11a and 12a adjacent to each other. Specifically, a pair of (typically, a plurality of) through holes are provided between the convex portions 11a and 12a adjacent to each other with an interval in the axial direction of the steel pipe, as in the modification examples shown in FIGS. It can also be formed.

  In the modification shown in FIGS. 5-7, in each convex part (11a, 12a) of a joint part (11,12), in the part of the side along the axial direction of a steel pipe, two semicircle-shaped notch parts ( 11c, 12c) are formed at intervals. These semicircular notches (11c, 12c) can be easily obtained by sequentially forming circular through-holes in the joint steel pipe using, for example, a drill according to the above-described manufacturing method. The modified examples shown in FIGS. 5 to 7 are advantageous in transmitting a required large force particularly in a joint structure of steel pipe piles (1, 2) having a large cross-sectional area.

  Moreover, in the above-mentioned embodiment, although this invention is applied with respect to joining of a pair of steel pipe piles, ie, the 1st steel pipe pile 1, and the 2nd steel pipe pile 2, it is not limited to this but three Needless to say, the present invention can be applied to the joining of the steel pipe piles described above.

It is a figure which shows the joining structure of the steel pipe pile concerning embodiment of this invention, Comprising: It is a perspective view which shows schematically the structure of the joint part attached to the edge part of a steel pipe pile. It is a perspective view which shows roughly the joining state which attached the pin member in the state which the edge part of a pair of steel pipe pile shown in FIG. 1 fitted mutually. It is a figure explaining the attachment state of the pin member in FIG. 2, Comprising: (a) is an expansion | deployment side view, (b) has shown sectional drawing along line AA of (a). It is a figure which shows roughly the structure of the prevention means for preventing that a pin member falls out from a through-hole in the joining state of this embodiment. It is a figure which shows the joining structure of the steel pipe pile concerning the modification of this embodiment, Comprising: It is a perspective view which shows schematically the structure of the joint part attached to the edge part of a steel pipe pile. It is a perspective view which shows roughly the joining state which attached the pin member in the state which the edge part of a pair of steel pipe pile shown in FIG. 5 fitted mutually. It is a figure explaining the attachment state of the pin member in FIG. 6, Comprising: (a) is an expansion | deployment side view, (b) has shown sectional drawing along line AA of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st steel pipe pile 2 2nd steel pipe pile 11 1st joint part 12 2nd joint part 11a, 12a Convex part 11b, 12b Concave part 11c, 12c Notch part 13 of convex part 13 Pin member (shear key)
21, 22 Factory welds

Claims (10)

In the structure to join a pair of steel pipe piles,
The end of the first steel pipe pile has a plurality of convex portions formed at intervals in the circumferential direction so as to protrude in the axial direction thereof,
The end of the second steel pipe pile has a shape substantially complementary to the shape of the end of the first steel pipe pile,
A hole having a predetermined shape is formed between the convex portions adjacent to each other in the fitted state between the end portion of the first steel pipe pile and the end portion of the second steel pipe pile, and a pin member inserted into the hole is interposed therebetween. The first steel pipe pile and the second steel pipe pile are connected to each other. The bonding structure according to claim 1, wherein a plurality of holes are formed between the convex portions adjacent to each other with an interval in the axial direction. The joint structure according to claim 1, wherein the hole is a circular through hole extending in a radial direction. The boundary surface formed between the convex portions adjacent to each other substantially coincides with a plane including the central axis of the circular through-hole and extending in the axial direction. Bonding structure. The joining structure according to any one of claims 1 to 3, further comprising prevention means for preventing the pin member from falling out of the hole. The said prevention means has a backing member attached to the inner side of the edge part of the said 1st steel pipe pile so that at least one part of the said hole may be covered, The joining structure of Claim 5 characterized by the above-mentioned. The prevention means is provided in the pin member so as to engage with at least one of an end portion of the first steel pipe pile and an end portion of the second steel pipe pile when the pin member is inserted into the hole. The joining structure according to claim 5, further comprising an engaging member. At the end of the first steel pipe pile, a first joint portion formed with the plurality of convex portions is attached by factory welding,
The second joint portion in which the plurality of convex portions are formed is attached to an end portion of the second steel pipe pile by factory welding, according to any one of claims 1 to 7. Junction structure. The joint structure according to claim 8, wherein the first joint portion and the second joint portion have the same shape. A method for manufacturing the first joint part and the second joint part according to claim 8 or 9,
A hole forming step of forming a plurality of holes having the predetermined shape spaced apart in the circumferential direction with respect to the steel pipe for a joint having a predetermined length;
The manufacturing method characterized by including the cutting process of cut | disconnecting the said steel pipe for joints in which the said several hole was formed to the uneven | corrugated shape corresponding to the boundary line of a said 1st joint part and a said 2nd joint part.

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