CN105658876A - Joint structure for steel pipe pile - Google Patents

Abstract

The joint structure of this steel pipe pile is a joint structure of steel pipe piles in which the first steel pipe pile and the second steel pipe pile are coaxially connected, and the closer to the outer block portion of the first steel pipe pile, the outer The thicker the plate thickness of the inlaid valley is formed, the closer it is to the inner section of the second steel pipe pile, the greater the plate thickness of the inlaid valley is formed, and when the inner end is inserted into the outer end In the state where the parts are rotated relative to each other and fitted, the inlay top surface and the opposite surface of the inlay top surface are separated by a predetermined separation distance (D), and the total area of the tension side abutment surface that bears the tension force is as follows The total area is less than or equal to the total area of the area of the outer fitting tip surface bearing the compressive force and the total area of the compression side abutting surface bearing the compressive force.

Description

Joint structure of steel pipe pile

technical field

The present invention relates to a joint structure of a steel pipe pile for connecting a first steel pipe pile and a second steel pipe pile in an axial center direction.

this application claims priority based on Japanese Patent Application No. 2013-252957 for which it applied to Japan on December 6, 2013, The content is used here.

Background technique

Conventionally, as a joint structure connecting the first steel pipe pile and the second steel pipe pile in the axial direction, welded joints and mechanical joints have been used.

The welded joint is obtained by butting the ends of the first steel pipe pile and the second steel pipe pile together and welding them. However, the joint structure of welded joints has difficulty in constructability, and the quality of the welded part and the working time are greatly affected by the site environment and the proficiency of the operator.

Then, as the joint structure of the steel pipe pile excellent in workability, as disclosed by patent document 1 and patent document 2, the joint structure of the steel pipe pile realized by the mechanical joint is proposed.

In the joint structure of steel pipe piles disclosed in Patent Document 1, a first pile and a second pile adjacent to each other in the axial center direction form a pair of outer fitting end portions and inner fitting end portions that can be freely fitted to each other. In addition, an engaging portion and an engaged portion are formed on the outer fitting end portion and the inner fitting end portion, and the engaging portion and the engaged portion are wound around the shaft in a state where the inner fitting end portion is inserted into the outer fitting end portion. The hearts rotate relative to each other and engage with each other.

In the joint structure of steel pipe piles disclosed in Patent Document 1, a separation prevention unit is provided on the engaging portion and the engaged portion to prevent the engaged engaging portion and the engaged portion from being separated from each other. The radial direction of the first pile or the second pile is separated.

In the joint structure of steel pipe piles disclosed in Patent Document 2, a first pile and a second pile adjacent to each other in the axial direction form a pair of outer fitting end portions and inner fitting end portions that can be freely fitted to each other. In addition, a plurality of engaging protrusions and engaged protrusions are formed in the axial direction at the outer fitting end and the inner fitting end, and the engaging protrusions and the engaged protrusions are inserted into the outer fitting end. In a state where the ends are fitted in, they are rotated around the axis and engaged with each other.

In the joint structure of the steel pipe pile disclosed in this patent document 2, in the outer fitting end part, the formation part of the engagement convex part provided on the front end part side is formed more than the engagement convex part provided on the base end part side. The diameter of the forming part of the convex part is large, and the forming part of the engaged convex part provided on the tip part side in the inner fitting end part is formed smaller than the engaged convex part provided on the proximal part side. The diameter of the formation site is small.

prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 11-43937

Patent Document 2: Japanese Patent Application Laid-Open No. 11-43936

Contents of the invention

The problem to be solved by the invention

In the joint structure of the steel pipe pile, the energy transmitted from the engaging part and the engaging convex part to the engaged part and the engaged convex part is transmitted from the base end side to the distal end side of the outer fitting end part and the inner fitting part part. The tensile force is reduced.

However, in the joint structure of the steel pipe pile disclosed in Patent Document 1, although the tensile force transmitted to the engaged portion decreases from the base end side to the distal end side of the outer fitting end portion and the inner fitting end portion, However, the plate thickness of the engaged portion is set to be the same in the axial direction. Therefore, in the joint structure of the steel pipe pile disclosed in Patent Document 1, there is particularly a problem that there are many useless plate thicknesses on the front end side of the outer fitting end and the inner fitting end, and the number of plates is increased more than necessary. Thick and incur cost increases.

On the other hand, in the joint structure of the steel pipe pile disclosed in Patent Document 2, the tensile force transmitted to the engaged convex part is transmitted from the base end side to the distal end side of the outer fitting end part and the inner fitting end part. Accordingly, the plate thickness of the engaged convex portion gradually decreases from the base end side to the tip end side. However, in the joint structure of the steel pipe pile disclosed in this patent document 2, there is a problem that since the plate thickness of the engaged convex part becomes small at the front end side of the outer fitting end part and the inner fitting end part, the outer The compression resistance of the engaged convex portion at the tip side of the fitting end portion and the embedded end portion is lowered, and buckling deformation occurs in the engaged convex portion.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a joint structure of steel pipe piles capable of reducing the plate thickness on the tip side of the outer fitting end and the inner fitting end. While suppressing an increase in material cost, buckling deformation of the thinnest portion on the tip side is prevented.

means of solving problems

The technical scheme of the present invention is as follows.

(1) The 1st aspect of this invention is the joint structure of the steel pipe pile which connected the 1st steel pipe pile and the 2nd steel pipe pile coaxially. The joint structure of the steel pipe pile includes an outer fitting end part provided on the first steel pipe pile, and a plurality of outer fitting parts formed along the extending direction of the first axis of the first steel pipe pile, and an inset end portion provided on the second steel pipe pile and formed with a plurality of inner segment portions along the extending direction of the second axis of the second steel pipe pile, the plurality of outer segment portions Each outer block portion includes: an outer fitting mountain portion protruding in a direction toward the first axis, and a plurality of outer fitting grooves are formed in a circumferential direction centered on the first axis; It is formed between each of the externally embedded mountain portions adjacent to each other; and an externally embedded valley portion is adjacent to each of the externally embedded mountain portions and is formed near the base end side of the first steel pipe pile, so that Each of the plurality of inner segment parts is provided with: a built-in mountain part, which protrudes in a direction away from the second axis, and is formed in a circumferential direction centered on the second axis. a plurality of; embedded grooves formed between the adjacent embedded peaks; and embedded valleys adjacent to each of the embedded peaks and formed near the second steel The base end side of the pipe pile, among the plurality of outer block parts, is closer to the outer block part of the first steel pipe pile, and the plate thickness of the outer embedded valley part is formed to be larger. Among the plurality of inner section parts, the closer to the inner section part of the second steel pipe pile, the greater the plate thickness of the inner valley part is formed. In the state where the outer fitting end is relatively rotated and fitted, the inner front end surface on the front end side of the inner fitting end is separated from the opposite surface of the inner front end surface by a predetermined separation distance D, and the plurality of Among the abutment surfaces between the outer block parts and the plurality of inner block parts, the total area of the stretch side abutment surfaces that bear the tensile force is not more than the following total area, and the total area is The total area of the area of the outer fitting front end surface on the tip side of the outer fitting end portion that bears the compression force and the total area of the compression side abutting surface that bears the compression force.

(2) In the joint structure of steel pipe piles described in (1) above, the total area of the tension-side contact surfaces may be equal to or less than the total area of the compression-side contact surfaces.

(3) In the joint structure of the steel pipe pile described in the above (1) or (2), the embedded mountain portion of the inner segment closest to the tip side of the embedded end may be In the section, when the protrusion height in the direction toward the second axis is defined as h, and the length in the extending direction of the second axis is defined as l, the predetermined separation distance D satisfies the following The formula (A) described above.

D≥(h ² +l ² ) ^0.5 -l...Formula (A)

(4) In the joint structure of steel pipe piles described in any one of (1) to (3) above, the protruding height of the embedded peaks of the plurality of embedded segments may be At least one of the protruding heights of each other and the outer fitting mountain portions of the plurality of outer block portions is substantially the same.

(5) In the joint structure of steel pipe piles described in any one of (1) to (4) above, the opposite surface of the embedded front end surface may be the outer embedded end portion. The outer embedded base end face of the base end side.

(6) In the joint structure of steel pipe piles described in any one of (1) to (4) above, the opposite surface of the embedded front end surface may be the first steel pipe pile end face.

The effect of the invention

According to the joint structure of the steel pipe pile described in the above (1), it has a structure in which, among the plurality of outer block parts, the closer the outer block part of the first steel pipe pile is, the greater the plate thickness of the outer embedded valley part becomes. The larger the value is, and the closer to the inner segment part of the second steel pipe pile among the plurality of inner segment parts, the larger the plate thickness of the embedded valley part is formed. Therefore, compared with the base end side, the plate thickness at the tip side where the transmitted tensile force and compressive force are small is reasonably reduced, so it is possible to prevent an increase in the cost of materials while preventing the most extreme outfitting. Buckling deformation of the thinnest part and the embedded thinnest part.

In addition, according to the joint structure of the steel pipe pile described in the above (1), in a state where the inner fitting end is inserted into the outer fitting end and relatively rotated coaxially to fit, the inner fitting on the front end side of the fitting end is The inlay top face and the opposing face of the inset top face are separated by a predetermined separation distance D. Therefore, it is possible to prevent the compressive force from the facing surface of the inlay distal end surface from being transmitted to the inlay distal end surface, so that buckling deformation of the thinnest inlay portion that is easily deformed when a compressive force acts can be prevented.

Furthermore, according to the joint structure of the steel pipe pile described in the above (1), among the abutment surfaces between the plurality of outer block parts and the plurality of inner block parts, the tension side that bears the tensile force is in contact with each other. The total area of the surfaces is not more than the total area of the area of the outer fitting tip surface on the tip side of the outer fitting end portion bearing the compressive force and the total area of the compression side abutting surface bearing the compressive force. Therefore, even if the compressive force that can be borne by the distal end surface of the outer fitting becomes smaller if the thinnest outer fitting part is buckled and deformed, the compressive force can be overcome by the compression side abutting surface of the remaining segment. Therefore, predetermined compression resistance can be maintained by the entire outer fitting end portion and the entire inner fitting end portion.

According to the joint structure of the steel pipe pile as described in said (2), the total area of a tension side contact surface is less than the total area of a compression side contact surface. Therefore, even if the thinnest outer fitting part is buckled and deformed and the compressive force cannot be borne by the outer fitting distal end surface, the compressive force can be overcome by the compression side abutting surface of the remaining segment. Therefore, predetermined compression resistance can be more reliably maintained by the entire outer fitting end portion and the entire inner fitting end portion.

According to the joint structure of the steel pipe pile described in said (3), separation distance D is set so that said Formula (A) may be satisfied. Therefore, even if the joint structure of the steel pipe pile is bent and deformed, the compressive force from the opposite surface of the embedded tip surface will not be transmitted to the embedded tip surface, so it is possible to more reliably prevent the compression force from being easily deformed. Buckling deformation of the thinnest part of the deformed insert.

According to the joint structure of steel pipe piles described in the above (4), the protrusion heights of the inner ridges in the plurality of inner segments and the protrusion heights of the outer ridges in the outer segments At least one side is substantially the same. Therefore, the machinability of the inner block portion and/or the outer block portion is improved.

According to the joint structure of the steel pipe pile described in the above (5) or (6), it is possible to adopt the outer embedded base end surface or the first steel pipe pile in which the opposite surface of the embedded distal end surface is the base end side of the outer embedded end. The structural design of the end face.

Description of drawings

Fig. 1 is a perspective view showing a joint structure of a steel pipe pile according to one embodiment of the present invention.

Fig. 2 is a view showing the fitting end portion of the joint structure, and is a sectional view when viewed along a section including the axis.

Fig. 3 is a view showing an external fitting end portion of the joint structure, and is a sectional perspective view of a main part.

Fig. 4 is a front view showing an embedded end portion of the joint structure.

Fig. 5 is a view showing an embedded end portion of the joint structure, and is a sectional perspective view of a main part.

Fig. 6 is a perspective view showing a state in which an inner fitting end is inserted into an outer fitting end of the joint structure.

Fig. 7 is a view showing a state in which an inner fitting end is inserted into an outer fitting end of the joint structure and relatively rotated, and is a partially cutaway perspective view.

Fig. 8 is a partial cross-sectional view showing the main part of the joint structure.

Fig. 9 is a partial sectional view showing a first modified example of the joint structure.

FIG. 10 is a partial cross-sectional view for explaining a preferable lower limit value of the separation distance D of the above-mentioned joint structure.

Fig. 11 is a partial sectional view showing a second modified example of the joint structure.

Fig. 12A is a bottom view showing the fitting end of the joint structure.

Fig. 12B is a plan view showing the fitting end of the joint structure.

Fig. 13A is a plan view showing the fitting end of the joint structure.

Fig. 13B is a bottom view showing the fitting end of the joint structure.

Fig. 14 is a cross-sectional view of main parts showing the tensile force acting on the fitting end portion of the joint structure.

Fig. 15 is a sectional view of main parts showing a compressive force acting on the fitting end portion of the joint structure.

Fig. 16 is a sectional view of main parts showing the tensile force acting on the embedded end portion of the joint structure.

Fig. 17 is a sectional view of main parts showing a compressive force acting on the fitting end portion of the joint structure.

Fig. 18A is a sectional view of main parts showing a third modified example of the joint structure.

Fig. 18B is a sectional view of main parts showing a fourth modified example of the joint structure.

Fig. 19 is a sectional view of main parts showing the abutment surface of the fitting end of the joint structure.

Fig. 20 is a sectional view of main parts showing the abutment surface of the fitting end of the joint structure.

detailed description

Hereinafter, the joint structure 7 of the steel pipe pile which concerns on one Embodiment of this invention (Hereinafter, it may be called the joint structure 7 of this embodiment or just the joint structure 7) is demonstrated in detail with reference to drawings.

In addition, in the following description, the direction in which the axial center of the steel pipe pile extends may be referred to as the axial direction Y, the direction perpendicular to the axial direction Y may be referred to as the axial direction X, and the direction around the steel pipe pile The direction of the axis is called the circumferential direction W.

As shown in FIG. 1 , the joint structure 7 of the present embodiment is set to include a first steel pipe pile having a first axis and a substantially circular cross-section among foundation piles or the like of a structure built on the foundation. 1 and a second steel pipe pile 2 having a second axis and having a substantially circular cross-section are connected coaxially (axis direction Y).

To the upper end portion of the first steel pipe pile 1 , the outer fitting end portion 3 in which a plurality of outer fitting segments 4 are formed along the axial direction Y is joined by welding or the like. In the lower end part of the 2nd steel pipe pile 2, the inlay end part 5 in which the some inlay segment parts 6 were formed along the axis direction Y is joined by welding etc. FIG. The outer fitting end portion 3 and the inner fitting end portion 5 have a structure that can be fitted freely with each other.

Each of the plurality of outer block portions 4 formed on the outer insert end portion 3 has an outer insert ridge portion 31 protruding in a direction toward its axis and formed with a plurality of Outer fitting groove portion 32, which is formed between each outer fitting mountain portion 31 adjacent to each other in the circumferential direction W; and outer fitting valley portion 33, which is adjacent to each outer fitting mountain portion 31 and formed near the first The base end side of the steel pipe pile.

In each of the outer block portions 4 , from the viewpoint of fit and workability, the outer fitting groove portion 32 and the outer fitting valley portion 33 are preferably formed with the same plate thickness as shown in FIG. 1 so as to be coplanar with each other.

In the joint structure 7 of the present embodiment, as shown in FIG. 1 , for each of the plurality of outer block portions 4 , four outer fitting ridges are formed at predetermined intervals in the circumferential direction W. part 31, but the present invention is not limited to this configuration.

Each of the plurality of inner segment portions 6 formed at the inner end portion 5 has an inner peak portion 51 protruding in a direction away from its axis, and formed in the circumferential direction W with multiple an embedded groove portion 52, which is formed between each adjacent embedded mountain portion 51 in the circumferential direction W; and an embedded valley portion 53, which is adjacent to each embedded mountain portion 51 and formed near the first 2 The base end side of the steel pipe pile.

In each inner segment 6 , it is preferable that the inner groove 52 and the inner valley 53 are formed with the same plate thickness as shown in FIG. 1 so as to be coplanar with each other from the viewpoint of fit and workability.

In the joint structure 7 of this embodiment, as shown in FIG. 1 , for each of the plurality of inner segment portions 6 , four inner ridges are formed at predetermined intervals in the circumferential direction W. portion 51, but the present invention is not limited to this configuration.

In addition, in the joint structure 7 of this embodiment, as shown in FIG. 1 , four key grooves P for inserting the rotation prevention key are formed in the circumferential direction W, but the key groove may not be formed, and the rotation prevention key is used for the rotation prevention key. Relative rotation after the fitting of the outer fitting end 3 and the inner fitting end 5 is prevented.

In the joint structure 7 of the present embodiment, as shown in FIG. 2 , four stages of the outer fitting portion 4 are formed in the axial direction of the outer fitting end portion 3 . That is, the outer fitting end portion 3 has a first outer fitting portion 41 , a second outer fitting portion 42 , and a third outer fitting portion 43 sequentially from the distal end side to the proximal end side in the axial direction Y of the outer fitting end portion 3 . , and the fourth outer block portion 44 .

In each outer block portion 4 , the thickness of the outer fitting groove portion 32 is set smaller than that of the outer fitting ridge portion 31 , and the outer fitting ridge portion 31 and the outer fitting groove portion 32 are alternately formed in the circumferential direction W. In addition, the outer fitting peaks 31 of the plurality of outer block parts 4 are arranged substantially in a row in the axial direction Y. As shown in FIG.

Similarly, in each of the outer insert segments 4 , the plate thickness of the outer insert valleys 33 is set to be smaller than the plate thickness of the outer insert peaks 31 , and the outer insert peaks 31 and the outer insert valleys 33 are aligned in the axial direction Y. formed alternately.

As shown in FIG. 3 , the thickness of the outer fitting valley portion 33 is formed to be greater as the outer block portion 4 is closer to the base end side of the outer fitting end portion 3 .

That is, the thickness of the outer fillet trough 33 of the first outer block part 41 is formed smaller than the thickness of the outer fillet 33 of the second outer block part 42, and the outer fillet 33 of the second outer block part 42 The plate thickness of the part 33 is formed to be smaller than the plate thickness of the outer insert valley part 33 of the third outer block part 43, and the plate thickness of the outer insert valley part 33 of the third outer block part 43 is formed to be smaller than that of the fourth outer block part. The plate thickness of the inlaid valley portion 33 of the portion 44 is small.

The outer fitting valley portion 33 of the first outer block portion 41 is formed as the thinnest outer fitting portion 30 with the smallest plate thickness in the outer fitting end portion 3 , and is formed in the axial direction of the outer fitting mountain portion 31 of the first outer block portion 41 . On the tip side of the Y, an outer fitting tip surface 34 is formed in a substantially planar shape.

In addition, a fitting excess length portion 45 is formed on the base end side of the fitting valley portion 33 of the fourth fitting portion 44 in the axial direction Y. On the distal end side of the fitting excess length portion 45 , the fitting base end surface 35 is formed over the entire circumference.

In the joint structure 7 of the present embodiment, as shown in FIG. 4 , four stages of the inner block portion 6 are formed in the axial direction Y of the inner end portion 5 . That is, the inset end portion 5 has a first inset segment portion 61, a second inset segment portion 62, and a third inset segment portion sequentially from the distal end side to the proximal end side in the axis direction Y of the inset end portion 5. 63, and the fourth inner block part 64.

In each inner segment 6 , the thickness of the inner groove 52 is set smaller than that of the inner ridge 51 , and the inner ridge 51 and the inner groove 52 are alternately formed in the circumferential direction W. In addition, the embedded mountain portions 51 of the plurality of inner segment portions 6 are arranged substantially in a row in the axial direction Y. As shown in FIG.

Similarly, in each of the embedded segment portions 6, the plate thickness of the embedded valley portion 53 is set to be smaller than the plate thickness of the embedded mountain portion 51, and the embedded mountain portion 51 and the embedded valley portion 53 are aligned in the axial direction Y. Alternately formed.

As shown in FIG. 5 , the thickness of the embedded valley portion 53 is formed to be larger as the inner step portion is closer to the base end side of the embedded end portion 5 .

That is, the plate thickness of the embedded valley portion 53 of the first internally inserted segment portion 61 is formed smaller than the plate thickness of the embedded valley portion 53 of the second internally inserted segment portion 62, and the embedded valley portion of the second internally inserted segment portion 62 The plate thickness of the part 53 is formed to be smaller than the plate thickness of the inlaid valley part 53 of the third inner insert part 63, and the plate thickness of the inlaid valley part 53 of the third inner insert part 63 is formed to be smaller than that of the fourth inner insert segment. The plate thickness of the embedded valley portion 53 of the portion 64 is small.

The inlay valley portion 53 of the first inlay segment portion 61 is formed as the inlay thinnest portion 50 with the smallest plate thickness in the inlay end portion 5 , and is formed in the axial direction of the inlay peak portion 51 of the first inlay segment portion 61 . On the distal end side of the Y, an inset distal end surface 54 is formed in a substantially planar shape.

In addition, on the proximal end side of the fitting valley portion 53 of the fourth fitting portion 64 in the axial direction Y, a fitting extra length portion 65 is formed. On the distal end side of the fitting extra length portion 65 , a fitting base end surface 55 is formed over the entire circumference.

In the joint structure 7 of this embodiment, in order to connect the first steel pipe pile 1 and the second steel pipe pile 2 coaxially, as shown in FIGS. 6 and 7 , the outer fitting end 3 and the inner fitting end 5 fit each other. In addition, FIG. 7 is a perspective view showing a state in which a part of the outer fitting end portion 3 is cut away.

Specifically, first, as shown in FIG. 6 , the inward fitting end 5 attached to the second steel pipe pile 2 is inserted into the outer fitting end 3 attached to the first steel pipe pile 1 . In each inner insert segment 6 , the height of the inner fitting ridge 51 in the direction X perpendicular to the axis is set so that it corresponds to the height in the direction X perpendicular to the axis X of the outer fitting groove 32 at the time of fitting. below the depth. Thereby, it becomes possible to pass the inner fitting mountain part 51 through the outer fitting groove part 32, and it becomes a structure.

Next, as shown in FIG. 7 , in a state where the inner fitting end 5 is inserted into the outer fitting end 3 , the first steel pipe pile 1 and the second steel pipe pile 2 are aligned in the circumferential direction W around the axis. relative rotation. In each inner segment portion 6, the depth of the inner valley portion 53 in the direction X perpendicular to the axis is designed to be the depth of the corresponding outer peak 31 in the direction X perpendicular to the axis X when fitting. above height. This provides a structure in which the outer fitting ridges 31 can be fitted into the inner fitting valleys 53 .

8 is a schematic cross-sectional view of a state in which the fitting end 5 of the joint structure 7 according to this embodiment is inserted into the fitting end 3 and relatively rotated. As shown in FIG. 8 , the joint structure 7 has: the outer fitting tip surface 34 on the tip side of the outer fitting end portion 3; ; the embedded tip surface 54 on the tip side of the embedded end portion 5;

As shown in FIG. 8, in the outer block portions 4 (the first outer block portion 41, the second outer block portion 42, and the third outer block portion 43) except the fourth outer block portion 44 and the In the inner segment parts 6 (the fourth inner segment part 64, the third inner segment part 63, and the second inner segment part 62) other than the inner segment part 61, the axis direction Y of the inner segment part 51 The length on the top is designed to be approximately equal to the length in the axial direction Y of the corresponding outer embedding valley portion 33 when fitting, and the length on the axial direction Y of the outer embedding mountain portion 31 is designed to be approximately equal to The corresponding length in the axial direction Y of the embedded valley portion 53 at the time of fitting. Thereby, the outer fitting peak 31 and the inner fitting peak 51 can be engaged in the axis direction Y. FIG.

On the other hand, in the fourth outer block portion 44 and the first inner block portion 61, as shown in FIG. The length in the Y direction of the axial center is small. As a result, at the inward facing portion 56 , the inward top end surface 54 is separated from the outer inlay base end surface 35 by a predetermined separation distance D (mm), and an inward gap 57 is formed at the inward facing portion 56 .

Fig. 9 is a schematic cross-sectional view showing a joint structure 107 of a steel pipe pile according to a first modified example of the present invention. In this joint structure 107 , the plate thickness of the externally fitted excess length portion 45 is set to be equal to the plate thickness of the externally fitted valley portion 33 of the fourth external block portion 44 . According to this structure, the material cost of the outer fitting end part 3 can be reduced, and the machinability of the outer fitting valley part 33 can be improved, and the manufacturing cost of the outer fitting end part 3 can be reduced.

In the case of this joint structure 107 , the facing surface of the embedded front end surface 54 is the end surface of the first steel pipe pile 1 . Therefore, at the inlay facing portion 56 , the inlay top end surface 54 is separated from its opposite surface, that is, the end face of the first steel pipe pile 1 by a predetermined separation distance D (mm), thereby forming an inlay gap 157 at the inlay facing portion 56 . .

By forming the fitting gaps 57 and 157 , it is possible to prevent the compressive force in the axial direction Y from being transmitted to the fitting tip surface 54 . Therefore, buckling deformation of the thinnest embedded part 50 can be prevented.

The separation distance D (mm) of the embedded gaps 57 and 157 only needs to exceed 0 mm. However, in order to prevent the compressive force in the axial direction Y from being transmitted to the embedded tip surface 54 even when the steel pipe pile is bent and deformed, it is preferable to set the separation distance D (mm) to satisfy the following expression ( 1).

D≥(h ² +l ² ) ^0.5 -l...Formula (1)

h (mm): Protrusion height of the inlay mountain portion in the direction toward the axis in the inlay segment portion closest to the tip side of the inlay end portion

l (mm): The length of the inlay mountain in the direction of extension of the axis in the inlay segment closest to the tip side of the inlay end

As shown in FIG. 10 , the above-mentioned formula (1) is derived assuming that the connection point between the thinnest inlay portion 50 and the inlay mountain portion 51 is used as the bending center point C to perform bending deformation.

That is, by setting the separation distance D (mm) to satisfy the above formula (1), even when the steel pipe pile is bent and deformed, it is possible to reliably avoid contact between the fitting front end surface 54 and its opposing surface.

FIG. 11 is a sectional view of main parts showing a joint structure 207 according to a second modified example of the present invention. Also in this joint structure 207 , an outer fitting gap 37 is formed in the outer fitting portion 36 similarly to the inner fitting portion 56 . According to this structure, it is possible to prevent the compressive force in the axial direction Y from being transmitted to the outer fitting tip surface 34 , and it is possible to prevent buckling deformation of the outer fitting thinnest portion 30 . Although not shown in the drawing, the thickness of the extra-fitting extra length portion 65 may be set to be equal to the thickness of the fitting valley portion 53 of the fourth inner segment portion 64 . In this case, the facing surface of the outer fitting front end surface 34 is the end surface of the second steel pipe pile 2 . In addition, the separation distance D' (mm) of the fitting gap 37 only needs to exceed 0 mm, and can be set so as to satisfy the following formula (2).

D'≥(h' ² +l' ² ) ^0.5 -l'...Formula (2)

h' (mm): Protrusion height of the outer fitting peak in the direction toward the axis in the outer block portion closest to the tip side of the outer fitting end

l' (mm): The length in the extending direction of the axis of the outer fitting mountain portion in the outer block portion closest to the tip side of the outer fitting end portion

However, the side of the inner facing portion 56 is more prone to buckling deformation when a compressive force acts due to eccentricity with respect to the steel pipe portion than the side of the outer fitting portion 36 . Therefore, the effect of preventing buckling deformation obtained by providing the outer fitting gap 37 is smaller than the effect of preventing buckling deformation obtained by providing the fitting gap 57 .

Next, the contact surface 8 of the joint structure 7 of this embodiment is demonstrated.

In the joint structure 7 of this embodiment, by inserting the inner fitting end 5 into the outer fitting end 3 and rotating it relatively, the outer fitting ridge 31 and the outer fitting ridge 31 are formed in each of the outer fitting 4 and inner fitting 6 . The abutting surfaces 8 where the embedded mountain portions 51 abut against each other in the axial direction Y are included.

In the state where the first steel pipe pile 1 and the second steel pipe pile 2 are connected, from the first steel pipe pile 1 and the second steel pipe pile 2 to the outer fitting end 3 and the inner fitting end 5 at the axial center When a tensile force and a compressive force are applied in the direction Y, for the tensile force and the compressive force acting in the axial direction Y, the abutment surface in the axial direction Y is formed by the outer embedding mountain portion 31 and the inner embedding mountain portion 51. 8 to overcome.

In the joint structure 7 of the present embodiment, as shown in FIGS. 12A and 12B , in each of the outer block portion 4 and the inner block portion 6 , the abutting portion where the outer fitting ridge portion 31 and the inner fitting ridge portion 51 abut against each other Among the joint surfaces 8 , the base end side of the outer fitting end portion 3 and the proximal end side of the inner fitting end portion 5 are tension-side abutment surfaces 81 that bear tensile force.

And, as shown in FIG. 12A and FIG. 12B , the outer embedding ridge portion 31 of the first outer block portion 41 and the inner embedding ridge portion 51 of the fourth inner embedding portion 64 have tension at the tension side contact surface 81. The area At1, the outer embedding mountain portion 31 of the second outer block portion 42 and the inner embedding mountain portion 51 of the third inner embedding portion 63 have a tensile area At2 at the tension side abutment surface 81, and the third outer block portion The outer embedded mountain portion 31 of the portion 43 and the inner embedded mountain portion 51 of the second inner block portion 62 have a tensile area At3 at the tension side abutment surface 81, and the outer embedded mountain portion 31 of the fourth outer block portion 44 The embedded peak portion 51 with the first inner block portion 61 has a stretched area At4 on the stretched side contact surface 81 .

In addition, in the joint structure 7 of the present embodiment, as shown in FIGS. 13A and 13B , in each of the outer block portion 4 and the inner block portion 6 , the outer fitting peak portion 31 and the inner fitting peak portion 51 are in contact with each other. Of the abutting surfaces 8, the distal end side of the outer fitting end portion 3 and the distal end side of the inner fitting end portion 5 are compression-side abutting surfaces 86 that bear a compressive force.

In addition, as shown in FIGS. 13A and 13B , the outer fitting ridge 31 of the second outer block 42 and the inner fitting ridge 51 of the fourth inner block 64 have a compression area Ac1 at the compression side contact surface 86 . The outer embedding hill portion 31 of the third outer block portion 43 and the inner embedding hill portion 51 of the third inner embedding portion 63 have a compression area Ac2 at the compression side contact surface 86, and the outer embedding area of the fourth outer block portion 44 The embedded mountain portion 51 of the embedded mountain portion 31 and the second inner segment portion 62 has a compression area Ac3 on the compression side contact surface 86 .

In the joint structure 7 of this embodiment, it has a structure in which the outer fitting distal end surface 34 abuts on the inner fitting base end surface 55 at the outer fitting opposing portion 36 , and on the other hand, at the inner fitting opposing portion 56 , the inner fitting tip The surface 54 is not in contact with the outer base end surface 35 .

Therefore, in the joint structure 7 of this embodiment,

(A) The tensile force acting in the axial direction Y is overcome only by the four tension-side abutting surfaces 81 where the outer fitting ridge 31 and the inner fitting ridge 51 abut against each other,

(B) With respect to the compressive force acting in the axial direction Y, only the outer fitting tip surface 34 on the tip side of the outer fitting end portion 3 and the three places where the outer fitting peak portion 31 and the inner fitting peak portion 51 contact each other The compression side abutment surface 86 to overcome.

In addition, in the case of the joint structure 207 ( FIG. 11 ) of the second modified example described above, in the case where the outer fitting part 36 is also formed with the outer fitting gap 37 in the same way as the inner fitting part 56 , in the joint Construct 207,

(A') The tensile force acting in the axial direction Y is overcome only by the four tension-side abutting surfaces 81 where the outer fitting ridge 31 and the inner fitting ridge 51 abut against each other,

(B') The compressive force acting in the axial direction Y is overcome only by the three compression-side abutting surfaces 86 where the outer fitting ridge 31 and the inner fitting ridge 51 abut against each other.

The total area (At1+At2+At3+At4) of the tensile side abutting surface 81 that bears the tensile force among the abutting surfaces 8 where the outer block portion 4 and the inner block portion 6 abut against each other, is the total area (Ac1+Ac2+Ac3) of the area of the outer fitting distal end surface 34 bearing the compressive force (0 in the case of the joint structure 207 of the second modification) and the compression side abutting surface 86 bearing the compressive force less than the total area of

In addition, it is preferable to form such that the total area (At1+At2+At3+At1+At2+At3+ At4) is equal to or less than the total area (Ac1+Ac2+Ac3) of the compression-side contact surface 86 bearing the compressive force.

In this way, in the joint structure 7 of this embodiment, although the number of stages forming the compression-side abutting surface 86 is smaller than the number of stages forming the tension-side abutting surface 81, the total area of the tension-side abutting surface 81 is set to be compressed. The contact surface 8 where the respective outer fitting peaks 31 and inner fitting peaks 51 abut against each other is formed such that the total area of the side contact surfaces 86 and the area of the outer fitting tip end surface 34 bearing the compressive force is equal to or smaller than the total area.

In addition, in the case where the keyway P for inserting the rotation prevention key is formed on the outer fitting top end surface 34, the "area of the outer fitting top end surface 34 bearing the compressive force" does not include the area of the part where the keyway is formed. The relative rotation after the fitting of the outer fitting end portion 3 and the inner fitting end portion 5 is prevented. This is because the rotation blocking key bears substantially no compressive force.

In the joint structure 7 of this embodiment, the total area of the area of the outer fitting distal end surface 34 bearing the compressive force and the total area of the compression side contact surface 86 is equal to or greater than the total area of the tension side contact surface 81, so that A compressive force equal to or greater than the tensile force applied in the axial direction Y can be overcome only by the outer end surface and the compression-side abutting surface 86 of each outer ridge portion 31 and inner ridge portion 51. .

In addition, when the total area of the compression-side contact surface 86 is equal to or greater than the total area of the tension-side contact surface 81, for a compressive force equal to or greater than the tensile force applied in the axial direction Y, It can be overcome only by the compression-side abutting surfaces 86 of the outer fitting ridges 31 and the inner fitting ridges 51 .

In the joint structure 7 of the present embodiment, even when the outer fitting distal end surface 34 and the inner fitting base end surface 55 abut at the outer fitting opposing portion 36 , there is no substantial fitting of the first outer block portion 41 . Since the compressive force acts on the mountain portion 31, it is not necessary to consider the compressive force acting on the outer fitting mountain portion 31 of the first outer block portion 41 in design.

FIG. 14 shows the tensile force transmitted in the fitted end portion 3 of the joint structure 7 of the present embodiment.

The outer fitting valley portion 33 of the first outer block portion 41 is transmitted with a tensile force acting on the outer fitting peak portion 31 of the first outer block portion 41 . The resultant force of the tensile force acting on the outer fitting peaks 31 of the first outer block portion 41 and the second outer block portion 42 is transmitted to the outer fitting valley portion 33 of the second outer block portion 42 . The outer fitting valleys 33 of the third outer block portion 43 are transmitted with tension acting on the outer fitting peaks 31 of the first outer block portion 41 , the second outer block portion 42 , and the third outer block portion 43 . The resultant force. The outer embedding valley portion 33 of the fourth outer block portion 44 is transmitted to the first outer block portion 41 , the second outer block portion 42 , the third outer block portion 43 , and the fourth outer block portion 44 . The resultant force of the stretching force of the externally embedded mountain portion 31 .

Similarly, FIG. 15 shows the compressive force transmitted in the fitting end portion 3 of the joint structure 7 of this embodiment.

The compressive force acting on the outer fitting peaks 31 of the second outer block portion 42 is transmitted to the outer fitting valley portion 33 of the second outer block portion 42 . The resultant force of the compressive force acting on the second outer block portion 42 and the outer fitting peak portion 31 of the third outer block portion 43 is transmitted to the outer fitting valley portion 33 of the third outer block portion 43 . The compressive force acting on the second outer block 42 , the third outer block 43 , and the outer recess 31 of the fourth outer block 44 is transmitted to the outer recess 33 of the fourth outer block 44 . the resultant force.

In this way, in the joint structure 7 of this embodiment, the tensile force and the compressive force transmitted from the outer fitting peak 31 to the outer fitting valley 33 are reduced from the base end side to the distal end side of the outer fitting end portion 3, so These tensile and compressive forces can be overcome even if the plate thickness of the outer fitting valley 33 is reduced on the distal end side of the outer fitting end portion 3 . Accordingly, by reducing the thickness of the outer fitting valley portion 33 from the base end side to the distal end side of the fitting end portion 3 , an increase in the thickness of the fitting end portion 3 as a whole is suppressed, and an increase in material cost can be suppressed.

In the joint structure 7 of the present embodiment, the plate thickness of the outer fitting valley portion 33 is reduced at the first outer block portion 41 on the distal end side of the outer fitting end portion 3 to suppress an increase in the material cost of the outer fitting end portion 3 . Simultaneously, by not exerting compressive force on the outer embedding ridge portion 31 of the first outer block portion 41 as much as possible, the outer embedding valley portion 33 at the first outer block portion 41 will not be substantially transmitted with compressive force, and the outer embedding can be prevented from being compressed. Buckling deformation of the thinnest part 30.

In addition, in the joint structure 7 of the present embodiment, even if a compressive force is applied to the outer fitting ridges 31 of the first outer fitting 41 , it is not expected that the outer fitting valleys 33 of the first outer fitting 41 have compression resistance. ability. Therefore, in the joint structure 7, even if the thinnest outer fitting portion 30 buckles and deforms due to the compressive force transmitted to the outer fitting valley portion 33 of the first outer block portion 41, The outer insert valley portion 33 of the block portion 42, the third outer block portion 43, and the fourth outer block portion 44 overcomes the compressive force, so that the entire outer insert end portion 3 can maintain a predetermined compression resistance.

FIG. 16 shows the tensile force transmitted in the embedded end portion 5 of the joint structure 7 of the present embodiment.

Tensile force acting on the embedded mountain portion 51 of the first inner segment portion 61 is transmitted to the inner valley portion 53 of the first inner segment portion 61 . The resultant force of the tensile force acting on the first inner segment portion 61 and the inner peak portion 51 of the second inner segment portion 62 is transmitted to the inner valley portion 53 of the second inner segment portion 62 . The embedded valley portion 53 of the third inner segment portion 63 is transmitted with the tension acting on the embedded peak portion 51 of the first inner segment portion 61 , the second inner segment portion 62 and the third inner segment portion 63 . The resultant force. The embedded valley portion 53 of the fourth inner segment portion 64 is transmitted with the force acting on the first inner segment portion 61 , the second inner segment portion 62 , the third inner segment portion 63 and the fourth inner segment portion 64 . The resultant force of the tensile force of the embedding mountain portion 51 is embedded.

Similarly, FIG. 17 shows the compressive force transmitted to the embedded end portion 5 of the joint structure 7 of this embodiment.

The compression force acting on the fitting mountain portion 51 of the second inner fitting portion 62 is transmitted to the fitting valley portion 53 of the second inner fitting portion 62 . The resultant force of the compressive force acting on the second inner segment part 62 and the third inner segment part 63 is transmitted to the inner valley part 53 of the third inner segment part 63 . The compression force acting on the second inner segment 62 , the third inner segment 63 , and the inner peak 51 of the fourth inner segment 64 is transmitted to the inner valley 53 of the fourth inner segment 64 . the resultant force.

In this way, in the joint structure 7 of the present embodiment, the tensile force and the compressive force transmitted from the embedded peak portion 51 to the embedded valley portion 53 are reduced from the base end side to the distal end side of the embedded end portion 5, so These tensile and compressive forces can be overcome even if the plate thickness of the inline valley portion 53 is reduced at the top end side of the inline end portion 5 . Thus, in the joint structure 7, the thickness of the embedded end portion 5 is suppressed from increasing in thickness as a whole by reducing the plate thickness of the embedded end portion 5 from the base end side to the distal end side of the embedded end portion 5. An increase in material cost can be suppressed.

In the joint structure 7, the plate thickness of the embedded valley portion 53 is reduced at the first inner segment portion 61 on the distal end side of the embedded end portion 5 to suppress an increase in the material cost of the embedded end portion 5. By means of the embedded gap 57, no compressive force is applied to the embedded peak 51 of the first inner segment portion 61, so that no compressive force is transmitted to the embedded valley portion 53 at the first inner segment portion 61, and the maximum embedded Buckling deformation of the thin portion 50 .

FIG. 18A shows a joint structure 307 according to a third modified example of the present invention. Like this joint structure 307, in some or all of the plurality of outer block portions 4 and inner block portions 6, the side surfaces in the axis-orthogonal direction X of the outer fitting valley portion 33 and the inner fitting peak portion 51 may be Sets the taper.

FIG. 18B shows a joint structure 407 according to a fourth modified example of the present invention. Like this joint structure 407, in some or all of the plurality of outer block parts 4 and inner block parts 6, the direction X in the direction X perpendicular to the axis of the inner insert valley part 53 and the outer insert peak part 31 may be The sides are set to taper.

In the joint structure 7 of this embodiment, as shown in FIG. 19 , from the top end side to the base end side of the outer fitting end portion 3 , the outer fitting peaks 31 of each outer fitting portion 4 are arranged at right angles to the axial center. Inner side in direction X.

In the joint structure 7 of the present embodiment, the radius r41 of the outer fitting ridge 31 from the central axis to the first outer block portion 41 and the outer fitting ridge 31 from the central axis to the second outer block portion 42 are defined. In the case of the radius r42 of 31, the radius r43 of the outer fitting ridge 31 from the central axis to the third outer block 43, and the radius r44 of the outer fitting ridge 31 from the central axis to the fourth outer block 44, Satisfy the relationship of r41>r42>r43>r44.

Furthermore, in the joint structure 7 of the present embodiment, as shown in FIG. 19 , the height of the outer fitting mountain portion 31 of the first outer block portion 41 on the base end side of the outer fitting end portion 3 is defined as ht1 , the height of the outer embedded mountain portion 31 of the second outer block portion 42 at the base end side of the outer embedded end portion 3 is defined as ht2, and the height of the outer embedded mountain portion 31 of the third outer block portion 43 located at the outer embedded When the height of the base end side of the end portion 3 is defined as ht3, and the height of the outer fitting mountain portion 31 of the fourth outer block portion 44 on the base end side of the outer fitting end portion 3 is defined as ht4, ht1≤ ht2≤ht3≤ht4 relationship.

Here, the heights of the outer fitting mountain portions 31 may be set to be substantially the same so as to satisfy the relationship of ht1=ht2=ht3=ht4. In this case, it is preferable from the viewpoint of the machinability of the outer fitting mountain portion 31 .

In addition, by following the relationship of r41>r42>r43>r44 and setting the height of the outer embedding hill portion 31 so as to satisfy the relationship of ht1<ht2<ht3<ht4, each outer block portion 4, the stretched area At1, stretched area At2, stretched area At3, and stretched area At4 are substantially the same.

Similarly, in the joint structure 7 of this embodiment, as shown in FIG. 19 , when the height of the outer fitting mountain portion 31 of the second outer block portion 42 on the front end side of the outer fitting end portion 3 is defined as hc1, The height of the base end side of the outer fitting end portion 3 of the outer fitting mountain portion 31 of the third outer block portion 43 is defined as hc2, and the height of the outer fitting mountain portion 31 of the fourth outer block portion 44 at the outer fitting end portion 3 is defined as hc2. In the case where the height of the base end side is defined as hc3, the relationship of hc1≤hc2≤hc3 is satisfied.

Here, the heights of the outer fitting ridges 31 may be set to be substantially the same so as to satisfy the relationship of hc1=hc2=hc3. In this case, from the viewpoint of the machinability of the outer fitting ridges 31, preferred.

In addition, by following the relationship of r41>r42>r43>r44 and setting the height of the outer embedding hill portion 31 so as to satisfy the relationship of hc1<hc2<hc3, the height of each outer block portion 4 may be In the outer fitting mountain portion 31, the compression area Ac1, the compression area Ac2, and the compression area Ac3 are substantially the same.

In the joint structure 7 of this embodiment, as shown in FIG. 20 , from the distal end side to the base end side of the embedded end portion 5, the embedded peak portion 51 of each inner segment portion 6 is arranged at the center of the axis. The outer side in the cross direction X.

In the joint structure 7 of the present embodiment, the radius r61 of the fitting ridge 51 from the central axis to the first inner segment 61 and the radius r61 of the fitting ridge 51 from the central axis to the second inner segment 62 are defined. In the case of the radius r62 of 51, the radius r63 of the embedded peak 51 from the central axis to the third inner segment part 63, and the radius r64 of the embedded peak 51 from the central axis to the fourth inner segment part 64, Satisfy the relationship of r61<r62<r63<r64.

Furthermore, in the joint structure 7 of the present embodiment, as shown in FIG. 20 , the height of the fitting peak 51 of the fourth inner segment 64 on the base end side of the fitting end 5 is defined as ht1 , the height of the base end side of the embedded end portion 5 of the embedded mountain portion 51 of the third inner embedded segment portion 63 is defined as ht2, and the embedded height of the embedded mountain portion 51 of the second inner embedded segment portion 62 is defined as ht2. When the height of the base end side of the end portion 5 is defined as ht3, and the height of the base end side of the insert end portion 5 of the first inner insert segment portion 61 is defined as ht4, ht1≥ The relationship of ht2≥ht3≥ht4.

Here, the heights of the embedded mountain portions 51 may be set to be substantially the same so as to satisfy the relationship of ht1=ht2=ht3=ht4. In this case, it is preferable from the viewpoint of the machinability of the embedded mountain portion 51 .

In addition, by following the relationship of r61<r62<r63<r64 and setting the height of the embedded mountain portion 51 so as to satisfy the relationship of ht1<ht2<ht3<ht4, each embedded segment portion 6, the stretched area At1, the stretched area At2, the stretched area At3, and the stretched area At4 are substantially the same.

Similarly, in the joint structure 7 of the present embodiment, as shown in FIG. 20 , the height of the fitting peak 51 of the fourth inner segment 64 on the front end side of the fitting end 5 is defined as hc1 , the height of the base end side of the embedded end portion 5 of the embedded mountain portion 51 of the third inner embedded segment portion 63 is defined as hc2, and the embedded height of the embedded mountain portion 51 of the second inner embedded segment portion 62 is defined as hc2. When the height of the proximal end side of the end portion 5 is defined as hc3, the relationship of hc1≧hc2≧hc3 is satisfied.

Here, the heights of the embedded mountain portions 51 may be set to be substantially the same so as to satisfy the relationship of hc1=hc2=hc3. In this case, it is preferable from the viewpoint of the machinability of the embedded mountain portion 51 .

In addition, it is also possible to set the height of the embedding mountain portion 51 in a way that satisfies the relationship of hc1<hc2<hc3 by following the relationship of r61<r62<r63<r64, so that the embedding in each inner segment part 6 In the mountain part 51, the compression area Ac1, the compression area Ac2, and the compression area Ac3 are substantially the same.

In addition, when the stretched area At1, the stretched area At2, the stretched area At3, and the stretched area At4 are set to be approximately the same, with respect to the stretching force acting in the axis direction Y, it is possible to insert This tensile force is overcome to an approximately equal degree in the outer fitting ridges 31 of the segment 4 and the inner fitting ridges 51 of the inner segment 6 .

In addition, by setting the compression area Ac1, the compression area Ac2, and the compression area Ac3 to be substantially the same, it is possible to fit the outer mountain portion 31 and the inner portion of each outer block portion 4 with respect to the compressive force acting in the axial direction Y. This compressive force is overcome substantially uniformly in the embedded mountain portion 51 of the block portion 6 .

Thus, in the joint structure 7, the tensile force and the compressive force acting in the axial direction Y can be passed through the outer fitting ridges 31 of the outer inserts 4 and the inner inserts 6 of the inner inserts 6. 51 overcomes the tensile force and compressive force approximately equally, thus reducing the waste of the structural load-carrying capacity of the outer embedded end portion 3 and the inner embedded end portion 5, and making the structural calculation for the tensile force and compressive force easier.

In the joint structure 7 of the present invention, as described above, the protrusion heights of the inner fitting peaks of the plurality of inner block parts and the protrusion heights of the outer fitting peaks of the plurality of outer block parts may be At least one of them is substantially the same.

"Substantially the same" in the invention of the present application means that manufacturing errors of about 20% are allowed. is roughly the same.

The examples of embodiment of the present invention have been described above in detail, but the above-mentioned embodiments are merely examples of implementation of the present invention and should not be construed to limit the technical scope of the present invention.

For example, the fitting end part 5 may be attached to the 1st steel pipe pile 1, and the fitting end part 3 may be attached to the 2nd steel pipe pile 2.

In addition, in the axial direction Y of the outer fitting end portion 3 and the inner fitting end portion 5 , an arbitrary number of outer fitting segment portions 4 and inner fitting segment portions 6 may be formed.

In addition, in each of the outer insert portion 4 and the inner insert portion 6 , the positions of the outer insert ridges 31 and the inner insert ridges 51 in the axis direction Y may be shifted and arranged in a substantially zigzag shape.

In addition, by cutting the end of the first steel pipe pile 1 or the second steel pipe pile 2, the first steel pipe pile 1 or the second steel pipe pile 2 itself may be provided with an externally fitted end. 3 or embedded end 5.

Industrial availability

According to the present invention, it is possible to provide a joint structure of a steel pipe pile capable of reducing the plate thickness on the front end side of the outer fitting end and the inner fitting end, thereby suppressing an increase in material cost and preventing the front end from Buckling deformation of the thinnest part of the side.

Explanation of reference signs

1: The first steel pipe pile; 2: The second steel pipe pile; 3: Outer embedded end; 30: Outer embedded thinnest part; 31: Outer embedded mountain; 32: Outer embedded groove; 33: Outer embedded valley Part; 34: the top end face of the outer insert; 35: the end face of the outer base; 36: the opposite part of the outer insert; 37: the outer insert gap; 4: the outer block part; 41: the first outer block part; 42: the second outer block Block part; 43: the 3rd outer block part; 44: the 4th outer block part; 45: the extra long part of the outer embedded part; 5: the inner embedded end; 50: the thinnest part of the inner embedded part; 51: the inner embedded mountain 52: embedded groove; 53: embedded valley; 54: embedded top surface; 55: embedded base end surface; 56: embedded opposite part; 57, 157: embedded gap; 6: embedded segment Part; 61: the 1st inner block part; 62: the 2nd inner block part; 63: the 3rd inner block part; 64: the 4th inner block part; 65: the built-in excess length part; 7, 107, 207, 307, 407: joint structure of steel pipe pile; 8: abutment surface; 81: abutment surface on tension side; 86: abutment surface on compression side; P: keyway; W: circumferential direction; X: positive axis Intersecting direction; Y: axis direction.

Claims (6)

1. A joint structure of a steel pipe pile, wherein a first steel pipe pile and a second steel pipe pile are coaxially connected, wherein the joint structure of the steel pipe pile is characterized in that it has: an outer embedded end portion provided on the first steel pipe pile and formed with a plurality of outer embedded segments along the extending direction of the first axis of the first steel pipe pile; and an inset end portion provided on the second steel pipe pile and formed with a plurality of inset segments along the extending direction of the second axis of the second steel pipe pile, Each of the plurality of outer block portions has: an externally embedded mountain portion, which protrudes in a direction toward the first axis, and is formed in a plurality in a circumferential direction centered on the first axis; an outer fitting groove portion formed between each of the outer fitting mountain portions adjacent to each other; and an outer embedded valley portion adjacent to each of the outer embedded mountain portions and formed near the base end side of the first steel pipe pile, Each of the plurality of inner segment portions has: an embedded mountain protruding in a direction away from the second axis, and a plurality of them are formed in the circumferential direction centered on the second axis; an embedded groove portion formed between each of the embedded mountain portions adjacent to each other; and an embedded valley portion adjacent to each of the embedded mountain portions and formed near the base end side of the second steel pipe pile, Among the plurality of outer block portions, the closer to the outer block portion of the first steel pipe pile, the greater the plate thickness of the outer embedded valley portion is formed, Among the plurality of inner sections, the closer to the inner section of the second steel pipe pile, the greater the plate thickness of the inner valley is formed, In a state where the fitting end portion is inserted into the fitting end portion and relatively rotated to fit, the fitting tip surface on the tip side of the fitting end portion is separated from the facing surface of the fitting tip surface. the predetermined separation distance D, Among the abutting surfaces between the plurality of outer block parts and the plurality of inner block parts, the total area of the tension-side abutting surfaces that bear the tensile force is not more than the following total area. The total area is the total area of the area of the outer fitting distal end surface on the distal side of the outer fitting end portion bearing the compressive force and the total area of the compression side contact surface bearing the compressive force. 2. The joint structure of steel pipe piles according to claim 1, wherein: The total area of the tension-side contact surfaces is equal to or less than the total area of the compression-side contact surfaces. 3. The joint structure of steel pipe piles according to claim 1, wherein: The joint structure is set to define a protrusion height in a direction toward the second axis in the in-line mountain portion of the in-line segment portion closest to the tip side of the in-line end portion. is h, and when the length in the extending direction of the second axis is defined as 1, the predetermined separation distance D satisfies the following formula (1), D≥(h ² +l ² ) ^0.5 -l... Formula (1). 4. The joint structure of steel pipe piles according to claim 1, characterized in that: At least one of the protrusion heights of the inner peaks of the plurality of inner block parts and the outer protrusion heights of the outer block parts is substantially the same. 5. The joint structure of steel pipe piles according to any one of claims 1 to 4, characterized in that: The facing surface of the inward distal end surface is an outboard proximal end surface on the proximal side of the outboard end portion. 6. The joint structure of steel pipe piles according to any one of claims 1 to 4, characterized in that: The facing surface of the embedded front end surface is an end surface of the first steel pipe pile.