JPWO2019111882A1 - Rotating pile joint structure - Google Patents

Abstract

The rotary pile joint structure (2) is formed on a pair of end plates (12, 22) fixed to the ends of the rotary piles (10, 20), one end plate (12) and the other end plate (22). It is provided with shear resistance portions (13, 33) that resist the rotational shear force of the rotary piles (10, 20).

Description

The present invention relates to a rotary pile joint structure.

Conventionally, a structure in which piles are driven into the ground has been adopted as the foundation structure of the above-ground structure. Rotational excavation is used as a method for driving piles.
In rotary excavation, steel pipe piles suitable for torque transmission are used, and the steel pipe piles are rotationally driven at the above-ground portion, and the blade plates formed on the outer periphery of the tip of the steel pipe piles dig into the ground. Then, each time the steel pipe pile enters the ground at a predetermined depth, a new pipe body is added to form a steel pipe pile reaching a desired depth.

Sufficient torque transmission performance for excavation is required at the connecting portion of the rotating pile.
In terms of torque transmission performance, it is desirable to weld the ends of the pipes together. However, it is necessary to secure a welding technician together with the welding equipment for the welding work, which causes problems such as complicated process and increase in work cost. Furthermore, welding using fire cannot be performed at the place where combustibles are handled at the place where the steel pipe pile is installed.

A mechanical pile joint structure is used as a connection structure that does not use welding.
For example, in the connection structure of steel pipe piles of Patent Document 1, the end plates of a pair of steel pipe piles are butted against each other, and the connection is maintained by bolts penetrating each end plate. Further, a key groove in the diameter direction is formed on the opposite surfaces of the end plates, and the key member is sandwiched in the groove at the time of abutting to prevent relative rotation and transmit torque.
Further, in the joint structure of piles of Patent Document 2, the joint end plates of a pair of piles are butted against each other, and the outer peripheral portions of the end plates are overlapped and connected by a connecting member. Further, by forming an elliptical key groove on the opposite surface of each end plate and sandwiching the elliptical torque transmission ring member in the groove at the time of abutting, relative rotation can be prevented and torque can be transmitted. I am doing it.

Japanese Unexamined Patent Publication No. 2008-274613 Japanese Unexamined Patent Publication No. 2016-89354

In each of the joint structures of Patent Document 1 and Patent Document 2 described above, a key groove is formed in each pair of end plates, and a key member for torque transmission is fitted therein.
Therefore, it is necessary to form a key groove corresponding to the key member on the end plate. Such a key groove has a problem that processing accuracy is required in order to make the shape and dimensions corresponding to the key member, cutting processing is required, and the processing cost increases.
Further, it is difficult to make the depth of the key groove more than half the thickness of the end plate, and there is a problem that the dimensions of each part increase more than necessary when trying to secure a sufficient transmission torque. For example, when the thickness of the key member is increased, the depth of the key groove also needs to be increased, and therefore the thickness of the end plate needs to be increased. As a result, the weight of the pile material increases, which affects the transportation and also raises the material cost.

An object of the present invention is to provide a rotary pile joint structure which is easy to process and can obtain a sufficient transmission torque even with a thin end plate.

The rotary pile joint structure of the present invention is provided on a pair of end plates fixed to the end portions of the rotary pile, one end plate and the other end plate, and shears against the rotational shear force of the rotary pile. It is characterized by including a resistance portion.

In the present invention, a shear resistance portion is provided on one end plate and the other end plate. The shear resistance portion can resist the rotational shearing force acting on the joint structure during the construction of the rotary pile. Therefore, when excavating the rotary pile, the upper rotary torque can be transmitted to the lower rotary pile to reliably perform the excavation work of the rotary pile.

In the joint structure of the rotary pile of the present invention, the shear resistance portion includes a pair of end plates fixed to the end portions of the rotary pile, engagement holes penetrating each of the end plates, and one end plate. It is preferable to have an engaging member inserted from the engaging hole of the above to the engaging hole of the other end plate.

In the present invention, the engaging hole may be a hole that penetrates the end plate and can be machined by punching or drilling, and is easier to machine than a key groove that is cut to a desired depth from the surface. is there.
Then, in the present invention, since the engaging holes are formed in the pair of end plates, the depth of the engaging holes is the thickness of the end plates.
Therefore, the engaging member inserted from one engaging hole to the other engaging hole engages with each end plate over the thickness of the end plate when the rotary pile receives torque, and ends. Torque can be transmitted by maximizing the thickness of the plate, and sufficient transmission torque can be obtained even with a thin end plate.
As a result, it is possible to obtain a rotary pile joint structure that is easy to process and can obtain a sufficient transmission torque even with a thin end plate.
A cylindrical steel pipe can be used as the rotary pile, a steel plate can be used as the end plate, and welding can be performed when fixing the end plate to the steel pipe. This welding may be performed in advance at a manufacturing factory or the like, and does not need to be performed at a pile driving site.

In the rotary pile joint structure of the present invention, the engagement hole is preferably a circular hole centered on a position away from the rotation center of the rotary pile.
In the present invention, a circular hole can be easily machined in the end plate with a drill or a cup saw. A rough pilot hole may be formed with a torch or the like to adjust the inner circumference to a cylindrical surface, and such a procedure can be processed more easily than a keyway.

In the rotary pile joint structure of the present invention, it is preferable that a plurality of the circular holes are arranged around the rotation center of the rotary pile.
In the present invention, by arranging a plurality of circular holes, even if each transmission torque is small, the number of circular holes can be increased to ensure transmission performance that can withstand a desired torque.

In the rotary pile joint structure of the present invention, the engaging member is preferably a round bar member inserted into the circular hole.
In the present invention, since the engaging hole is a circular hole, a round bar member can be used as the engaging member. For example, an engaging member can be obtained by cutting a commercially available steel bar to a predetermined length. Therefore, it is easy to secure the engaging member, and the material cost can be reduced.

In the rotary pile joint structure of the present invention, the engagement hole is a polygonal hole concentric with the rotation center of the rotary pile, and the engagement member is a polygonal plate material capable of engaging with the engagement hole. Is preferable.
Specifically, as the polygon of the engaging hole and the engaging member, a hexagon or an octagon can be considered.
In the present invention, the unevenness of the inner peripheral edge of the engaging hole and the unevenness of the outer peripheral edge of the engaging member are engaged with each other, and the torque of the rotary pile can be transmitted. In particular, since the contours of the engaging hole and the engaging member are hexagonal or octagonal, for example, with respect to a rectangular end plate, a part of the edge of the engaging hole and the engaging member is parallel to the edge of the end plate. If so, the other edges are diagonally arranged so as to straddle the four corners of the end plate, and engagement holes are formed close to the four corners of the end plate where fastening bolts and the like are installed and strength is required. It is possible to suppress a decrease in strength due to this.
Further, the engaging holes formed in the end plate need only have one large hexagonal or octagonal opening, and the structure and processing can be simplified as compared with the case where a plurality of engaging holes having a small diameter are formed, for example. ..
When the contours of the engaging hole and the engaging member are hexagonal, the unevenness of the inner peripheral edge of the engaging hole and the unevenness of the outer peripheral edge of the engaging member can be engaged with each other at an acute angle. Therefore, even if an excessive rotational shearing force is applied, the inner peripheral edge of the engaging hole is not deformed and the engagement of the unevenness is not impaired, and the rotary pile joint structure can reliably transmit the rotational shearing force. it can.

In the rotary pile joint structure of the present invention, the engagement hole is a flat hole having a minor axis and a major axis having different inner edge lengths from the rotation center of the rotary pile, and the engaging member is the above. It is preferably a flat plate material that can engage with the flat hole.
In the present invention, since the engaging hole and the engaging member are formed flat, even if a rotary shear force acts on the rotary pile joint structure, the rotary shear force can be resisted at the flat portion, and the rotary shear force can be applied. A rotary pile joint structure that can reliably transmit can be used.

In the rotary pile joint structure of the present invention, the shear resistance portion has an engaging convex portion formed on the outer periphery of one of the end plates and an engaging concave portion formed on the outer periphery of the other end plate. Is preferable.
In the present invention, since the shear resistance portion has an engaging convex portion and an engaging concave portion formed on the outer periphery of the end plate, it is possible to resist the rotational shearing force on the outer periphery of the end plate. Therefore, since the shear resistance portion can be formed only by processing the outer peripheral edge of the end plate, the number of parts can be reduced and the workability can be improved.

In the rotary pile joint structure of the present invention, the end plate is a rectangular plate material having bolt holes at four corners and fixed to the end of the rotary pile, and a pair of fastening bolts is inserted into the bolt holes. It is preferable that they are connected to each other.
In the present invention, fastening with fastening bolts can be performed on the outside of the rotating pile, and the connection work can be facilitated.

In the rotary pile joint structure of the present invention, the end plate is a pair of circular plate materials having a plurality of bolt holes at positions protruding from the outer peripheral surface of the rotary pile and fixed to the end of the rotary pile. Are preferably connected to each other by fastening bolts inserted into the bolt holes.
In the present invention, fastening with fastening bolts can be performed on the outside of the rotary pile, the connection work can be facilitated, and fastening with fastening bolts can be performed at three or more locations along the outer peripheral edge of the end plate. Therefore, it is possible to improve the strength against the pulling force of the rotary pile joint structure.

According to the present invention, it is possible to provide a rotary pile joint structure that is easy to process and can obtain a sufficient transmission torque even with a thin end plate.

The side view which shows the rotary pile joint structure of 1st Embodiment of this invention. The vertical sectional view which shows the rotary pile joint structure of the 1st Embodiment. The horizontal sectional view which shows the rotary pile joint structure of the 1st Embodiment. The vertical sectional view which shows the manufacturing procedure of the 1st Embodiment. The plan view which shows the manufacturing procedure of the 1st Embodiment. The vertical sectional view which shows the assembly procedure of the 1st Embodiment. The plan view which shows the rotary pile joint structure of 2nd Embodiment of this invention. The plan view which shows the rotary pile joint structure of 3rd Embodiment of this invention. FIG. 5 is a vertical sectional view showing a rotary pile joint structure according to a fourth embodiment of the present invention. A plan view seen from the cross section taken along line BB in FIG. 9A. FIG. 9 is a plan view seen from the cross section taken along the line CC of FIG. 9A. The side view which shows the rotary pile joint structure of 5th Embodiment of this invention. 10A is a plan view seen from a cross section taken along line BB. The plan view which shows the rotary pile joint structure of 6th Embodiment of this invention. FIG. 11A is a vertical cross-sectional view taken along the line BB. FIG. 11A is a vertical cross-sectional view taken along the line CC. The plan view which shows the rotary pile joint structure of 7th Embodiment of this invention. FIG. 12A is a vertical cross-sectional view taken along the line BB of FIG. 12A. The plan view which shows the rotary pile joint structure of 8th Embodiment of this invention. The plan view which shows the rotary pile joint structure which becomes the modification of the 8th Embodiment.

[First Embodiment]
In FIG. 1, the rotary piles 10 and 20 are sequentially connected to form a pile 1, and the respective ends are connected to each other by a rotary pile joint structure 2 based on the present invention.
The rotary piles 10 and 20 have end plates 12 and 22 for connection at the ends of the pipe bodies 11 and 21.
The pipe bodies 11 and 21 are steel pipes having a circular cross section, and the end plates 12 and 22 are substantially square steel plates with corners cut off, and these are fixed to each other by welding.

As shown in FIGS. 2 and 3, the rotary piles 10 and 20 are connected by overlapping the end plates 12 and 22 with each other and tightening the four corners with bolts 31 and nuts 32.
A plurality of (for example, four) engaging holes 13 and 23 are formed in the end plates 12 and 22 in the region inside the pipe bodies 11 and 21, and a columnar engaging member 33 is formed in each of the end plates 12 and 22. It has been inserted.

The engagement holes 13 and 23 are circular holes centered on positions away from the rotation centers of the rotary piles 10 and 20, respectively. The engaging holes 13 and 23 are formed at corresponding positions on the surfaces of the end plates 12 and 22 and become continuous holes when the rotary piles 10 and 20 are connected to each other.
The engaging member 33 is formed by cutting a steel bar having a diameter that can be fitted into the engaging holes 13 and 23 with a predetermined length in the axial direction. The axial length of the engaging member 33 is aligned with the thickness of the end plates 12 and 22 overlapped.
Therefore, the engaging member 33 can be inserted into the continuous holes formed by the engaging holes 13 and 23 with the rotary piles 10 and 20 connected to each other. Then, in the inserted state, both end surfaces of the engaging member 33 are aligned with the surfaces of the overlapped end plates 12 and 22 (the surface opposite to the side in close contact with each other).

A plurality of (for example, four) stoppers 14 and 24 are fixed to the surfaces of the end plates 12 and 22 along the periphery of the engaging holes 13 and 23. The stoppers 14 and 24 are steel plate pieces, which are fixed to the end plates 12 and 22 by welding.
When the engaging member 33 is inserted into the engaging holes 13 and 23, both end surfaces of the engaging member 33 are brought into contact with the stoppers 14 and 24 to prevent them from escaping from the engaging holes 13 and 23. To.

Communication holes 15 are formed in the centers of the end plates 12 and 22, respectively. Through the communication holes 15, the insides of the rotary piles 10 and 20 are communicated with each other when they are connected to each other, and water and air can flow.
Bolt holes 16 (see FIG. 5) are formed at the four corners of the end plates 12 and 22, respectively, and bolts 31 can be inserted therethrough.

In the present embodiment, the rotary piles 10 and 20 are manufactured in advance at a predetermined manufacturing place. Then, the rotary piles 10 and 20 are transported to a predetermined installation location and driven into the ground as piles 1.
When driving the pile 1, the rotary pile 20 is first made to enter the ground by rotary excavation. When the rotary pile 20 reaches a predetermined depth, the rotary pile 10 is added, and the rotary pile 20 is further driven into the ground by rotary excavation.
When the rotary piles 10 and 20 are added, the rotary pile joint structure 2 is assembled, and the rotary piles 10 and 20 are connected via the rotary pile joint structure 2 to form a series of piles 1.

The rotary piles 10 and 20 are manufactured by the following procedure.
In FIGS. 4 and 5, first, end plates 12 and 22 having a predetermined shape are created. That is, steel plates corresponding to the end plates 12 and 22 are prepared, and engaging holes 13 and 23, communication holes 15 and bolt holes 16 are formed therein. Stoppers 14 and 24 are fixed around the engaging holes 13 and 23.
Next, the processed end plates 12 and 22 are arranged at the ends of the pipe bodies 11 and 21 prepared separately, and are welded and fixed over the entire circumference of the end edges of the pipe bodies 11 and 21.

The pile 1 is not limited to the two rotary piles 10 and 20, and three or more rotary piles are added according to the depth thereof. In this case, if the end plate 12 is formed at the lower end of one rotary pile and the end plate 22 is formed at the upper end, a large number of rotary piles can be sequentially connected by the rotary pile joint structure 2.

The rotary pile joint structure 2 is assembled by the following procedure.
As shown in FIG. 6, first, the engaging members 33 are fitted into the engaging holes 23 of the end plate 22 of the rotary pile 20. The engaging member 33 is locked to the stopper 24 and does not fall downward, and the upper half is in a state of protruding from the end plate 22.

Next, the rotary pile 10 is lifted by a crane or the like, and the end plate 12 faces the end plate 22. Then, the rotary stake 10 is gradually lowered so that each of the engaging holes 13 fits into the engaging member 33 protruding from the end plate 22, and further lowered to overlap the end plates 12 and 22.
After that, the four corners of the end plates 12 and 22 are tightened with bolts 31 and nuts 32. As a result, the rotary pile joint structure 2 is formed, and by rotationally driving the upper rotary pile 10, torque is transmitted to the lower rotary pile 20 via the rotary pile joint structure 2, and rotary excavation can be restarted.

According to the above-described embodiment, the following effects can be obtained.
In the rotary pile joint structure 2 of the present embodiment, the connection of the end plates 12 and 22 is maintained by the bolt 31 and the nut 32, and the torque transmission between the end plates 12 and 22 is performed by the engagement holes 13 and 23. And via the engaging member 33. Therefore, it is possible to avoid applying an excessive shearing force to the bolt 31 and the nut 32.

In the present embodiment, the engaging holes 13 and 23 may be holes that penetrate the end plates 12 and 22, and can be machined by punching or drilling, and a key groove that is cut to a desired depth from the surface. It is easier to process than.

In the present embodiment, since the engaging holes 13 and 23 are formed in the pair of end plates 12 and 22, the depth of the engaging holes 13 and 23 is the thickness of the end plates 12 and 22.
Therefore, the engaging member 33 inserted from one engaging hole 13 to the other engaging hole 23 has an end plate for each of the end plates 12 and 22 when the rotary piles 10 and 20 receive torque. Engagement over the entire thickness of 12 and 22, torque can be transmitted by maximizing the thickness of the end plates 12 and 22, and sufficient transmission torque can be obtained even with thin end plates 12 and 22.
As a result, the rotary pile joint structure 2 can be formed so that it is easy to process and sufficient transmission torque can be obtained even with thin end plates 12 and 22.

Cylindrical steel pipes can be used as the pipe bodies 11 and 21 of the rotary piles 10 and 20, steel plates can be used as the end plates 12 and 22, and the end plates 12 and 22 can be used as the pipe bodies 11 and 21. Welding can be performed when fixing to. This welding may be performed in advance at a manufacturing factory or the like, and does not need to be performed at a pile driving site.

In the present embodiment, since the engagement holes 13 and 23 are circular holes centered on positions away from the rotation centers of the rotary piles 10 and 20, the rotation centers of the rotary piles 10 and 20 are rotated via the engagement member 33. The torque can be reliably transmitted.
On the other hand, when machining the engaging holes 13 and 23, circular holes can be easily machined in the end plates 12 and 22 with a drill or a cup saw. A rough pilot hole may be formed with a torch or the like to adjust the inner circumference to a cylindrical surface, and such a procedure can be processed more easily than a keyway.

In the present embodiment, it is assumed that a plurality (for example, four) of the circular engaging holes 13 and 23 are arranged around the rotation center of the rotary piles 10 and 20, so that the number of the circular engaging holes 13 and 23 is increased even if the individual transmission torques are small. As a result, transmission performance that can withstand the desired torque can be ensured.
In the present embodiment, since the engaging holes 13 and 23 are circular holes, a round bar member can be used as the engaging member 33. The engaging member 33 can be easily obtained by cutting a commercially available steel bar to a predetermined length. Therefore, it is easy to secure the engaging member 33, and the material cost can be reduced.

In the present embodiment, the end plates 12 and 22 are formed from a rectangular plate material and are fastened to each other by bolts 31 and nuts 32 at the four corners, so that the material cost is reduced and the connection work is facilitated. Can be done.

[Second Embodiment]
FIG. 7 shows the rotary pile joint structure 2A of the second embodiment of the present invention.
This embodiment has the same basic configuration as the pile 1, the rotary pile joint structure 2, and the rotary piles 10 and 20 of the first embodiment described above. Therefore, the description of the common part is omitted, and only the difference part will be described below.

In the first embodiment described above, as shown in FIG. 3, four circular engaging holes 13 and 23 are formed in the end plates 12 and 22 of the rotary piles 10 and 20, and four engaging members 33 are formed therein. The torque was transmitted by inserting it.
On the other hand, in the present embodiment, as shown in FIG. 7, the end plate 12A is fixed to the end of the pipe body 11 to form the rotary pile 10A. An octagonal engaging hole 13A is formed in the end plate 12A, and an octagonal steel plate engaging member 33A is inserted through the octagonal engaging hole 13A.
Although not shown, a similar octagonal engaging hole 13A is formed in the rotating pile 10A of the other party to be connected, and torque can be transmitted by the engaging member 33A through which each is inserted.

In the first embodiment described above, as shown in FIG. 3, a communication hole 15 that communicates with the inside of the rotary piles 10 and 20 is formed at the center of the end plates 12 and 22.
On the other hand, in the present embodiment, as shown in FIG. 7, a communication hole 331 is formed at the center of the octagonal engaging member 33A.
Bolt holes 16 are formed at the four corners of the end plate 12A, and bolts can be fastened in the same manner as in the first embodiment described above.

Also in this embodiment as described above, sufficient torque can be sufficiently transmitted between the rotary piles 10A by the octagonal engaging holes 13A and the engaging members 33A.
That is, the unevenness of the inner peripheral edge of the engaging hole 13A and the unevenness of the outer peripheral edge of the engaging member 33A are engaged with each other, and the torque of the rotary pile 10A can be transmitted.
In particular, since the contours of the engaging hole 13A and the engaging member 33A are octagonal, for example, with respect to the rectangular end plate 12A, a part of the edge of the engaging hole 13A and the engaging member 33A is the side of the end plate 12A. If it is parallel to the edge, the other edge is diagonally arranged so as to straddle the four corners of the end plate 12A, and the engagement hole 13A is provided with respect to the four corners of the end plate 12A where fastening bolts and the like are installed and strength is required. It is possible to suppress a decrease in strength due to the formation of.
Further, the engagement hole 13A formed in the end plate 12A need only have one large octagonal opening, and has four engagement holes 13, 23 and communication holes 15 as in the first embodiment described above. The structure and processing can be simplified as compared with the case of forming.

[Third Embodiment]
FIG. 8 shows the rotary pile joint structure 2B of the third embodiment of the present invention.
This embodiment has the same basic configuration as the pile 1, the rotary pile joint structure 2, and the rotary piles 10 and 20 of the first embodiment described above. Therefore, the description of the common part is omitted, and only the difference part will be described below.

In the first embodiment described above, as shown in FIG. 3, four circular engaging holes 13 and 23 are formed in the end plates 12 and 22 of the rotary piles 10 and 20, and four engaging members 33 are formed therein. The torque was transmitted by inserting it.
On the other hand, in the present embodiment, as shown in FIG. 8, the rotary pile 10B is formed by fixing the end plate 12B to the end of the pipe body 11. A "+" -shaped engaging hole 13B is formed in the end plate 12B, and a "+" -shaped steel plate engaging member 33B is inserted therethrough.
Although not shown, a similar "+" -shaped engaging hole 13B is formed in the rotating pile 10B of the other party to be connected, and torque can be transmitted by the engaging member 33B through which each is inserted.

In the first embodiment described above, as shown in FIG. 3, a communication hole 15 that communicates with the inside of the rotary piles 10 and 20 is formed at the center of the end plates 12 and 22.
On the other hand, in the present embodiment, as shown in FIG. 8, a communication hole 331 is formed at the center of the “+” shaped engaging member 33B.
Bolt holes 16B are formed at the four corners of the end plate 12B, and bolts can be fastened in the same manner as in the first embodiment described above.
The bolt hole 16B of the present embodiment is an elongated hole extending around the center of the pipe body 11, and the angular position around the central axis of the connected rotary pile 10B can be adjusted.

Even with this embodiment as described above, sufficient torque transmission is possible as in the second embodiment described above, and the structure and processing can be simplified.

[Fourth Embodiment]
9A to 9C show the rotary pile joint structure 2C of the fourth embodiment of the present invention. 9A is a vertical cross-sectional view, FIG. 9B is a plan view seen from the BB line cross section of FIG. 9A, and FIG. 9C is a plan view seen from the CC line cross section of FIG. 9A.
This embodiment has the same basic configuration as the pile 1, the rotary pile joint structure 2, and the rotary piles 10 and 20 of the first embodiment described above. Therefore, the description of the common part is omitted, and only the difference part will be described below.

As shown in FIGS. 9B and 9C, the end plate 12C provided at the end of the tube 11 and the end plate 22C provided at the end of the tube 21 are circular steel plates, and the outer peripheral edge thereof is a circular steel plate. The pipe bodies 11 and 21 project outward from the outer peripheral surface and are fixed in a flange shape.
The end plates 12C and 22C are formed with an engaging hole 13C which is the center of the circular steel plate and is centered on the rotation center of the pipe body 11 and the pipe body 21, and the contour of the inner peripheral edge of the engaging hole is polygonal. It is said to be a regular hexagon.

The engaging member 33C is inserted into the engaging hole 13C with a gap. The engaging member 33C has a regular hexagonal outer peripheral contour, and is composed of a steel plate having a thickness larger than the sum of the plate thicknesses of the end plate 12C and the end plate 22C. A communication hole 331 is formed in the center of the engaging member 33C, and even if earth and sand enter the pipe body 21 when excavating the rotary pile 20 with an open tip, the earth and sand are poured into the upper pipe body 11 for excavation. The resistance is reduced.

As shown in FIGS. 9B and 9C, the portions of the end plates 12C and 22C that protrude outward from the outer peripheral surfaces of the pipe bodies 11 and 21 are along the circumference centered on the circular center of the end plates 12C and 22C. , A plurality of bolt holes 16 are formed, for example, 6 places.
The bolt holes 16C are formed as elongated holes extending in the circumferential direction of the end plates 12C and 22C. The clearance of the elongated holes should be larger than the gap between the engaging holes 13C and the engaging member 33C so that the bolts 31 do not come into contact with the bolt holes 16C when the bolt holes 16C of the end plates 12C and 22C are overlapped with each other. Just do it. In short, the clearance may be a size such that the rotational shear force does not act on the bolt 31, and may be a circular hole larger than the diameter of the bolt 31 instead of a long hole.

As shown in FIGS. 9A and 9B, on the lower surface of the end plate 22C, three stoppers 14A are provided around the hexagonal engaging hole 13C in units of 120 degrees. The stopper 14A has a cantilever support structure fixed to the lower surface of the end plate 22C at the outer peripheral end by welding or the like, and projects inside the engagement hole 13C to support the load of the engagement member 33C.
On the other hand, as shown in FIGS. 9A and 9C, there are two stoppers 14B on the upper surface of the end plate 12C parallel to the facing apex angle of the hexagonal engaging hole 13C and straddling the engaging hole 13C. It is provided.

Both ends of the stopper 14B are fixed to the upper surface of the end plate 12C by welding or the like, and the double-sided support structure regulates the upward lifting of the engaging member 33C.
As shown in FIG. 9A, a recess 141 corresponding to the shape of the engaging hole 13C is formed on the lower surface of the stopper 14B. The recess 141 is set to a height dimension that can be absorbed even if the upper surface of the engaging member 33C protrudes from the upper surface of the end plate 12C when the engaging member 33C is engaged with the engaging hole 13C.

According to such an embodiment, in addition to the effects described in each of the above-described embodiments, there are the following effects.
One end plate 12C and the other end plate 22C are provided with an engagement hole 13C and an engagement member 33C which serve as shear resistance portions. The shear resistance portion can resist the rotational shearing force acting on the joint structure during the construction of the rotary piles 10 and 20. Therefore, when excavating the rotary piles 10 and 20, the upper rotational torque can be transmitted to the lower rotary pile, and the excavation work of the rotary piles 10 and 20 can be surely performed.

Since the contours of the engaging hole 13C and the engaging member 33C are hexagonal, the unevenness of the inner peripheral edge of the engaging hole 13C and the unevenness of the outer peripheral edge of the engaging member 33C can be engaged at an acute angle. Therefore, even if an excessive rotational shearing force acts, the inner peripheral edge of the engaging hole 13C is not deformed and the engagement of the unevenness is not impaired, and the rotational shearing force can be reliably transmitted.
Since the outer circumferences of the end plates 12C and 22C are circular, the bolts 31 can be fastened at three or more locations along the outer peripheral edge of the end plates, so that the strength is strong against the pulling force of the rotary pile joint structure 2C. Can be improved.

The bolt holes 16C are formed as elongated holes extending along the circumferential direction of the end plates 12C and 22C, and the clearance is set larger than the gap between the engaging holes 13C and the engaging member 33C. Therefore, even if the end plates 12C and 22C are displaced in the rotational direction due to the gap between the engaging hole 13C and the engaging member 33C by applying a rotational shearing force during the construction of the rotary piles 10 and 20, the bolt 31 rotates. Shear force does not act. Therefore, the rotational shearing force acts on the bolt 31 during the construction, and the bolt 31 does not undergo shear failure.

Since the stopper 14B straddles the engaging hole 13C and holds the engaging member 33C with a double-sided support structure, it is possible to reliably prevent the engaging member 33C from rising. Therefore, during the rotary excavation work, the engaging member 33C is prevented from falling out of the engaging hole 13C against the earth pressure of the earth and sand flowing through the communication hole 331 of the engaging member 33C.

[Fifth Embodiment]
10A and 10B show the rotary pile joint structure 2D of the fifth embodiment of the present invention. 10A is a vertical side view, and FIG. 10B is a plan view seen from a cross section taken along the line BB of FIG. 10A.
This embodiment has the same basic configuration as the pile 1, the rotary pile joint structure 2, and the rotary piles 10 and 20 of the first embodiment described above. Therefore, the description of the common part is omitted, and only the difference part will be described below.

As shown in FIGS. 10A and 10B, the end plates 12D and 22D are made of circular steel plates, and three recesses are formed at every 120 degrees in the circumferential direction in a plan view. Cylindrical square steel pipe 16D is inserted into each recess of the end plates 12D and 22D. Each square steel pipe 16D is fixed to the outer peripheral surfaces of the pipe bodies 11, pipe bodies 11 and 21 by fillet welding or the like. ing.
The vertical end faces of the square steel pipe 16D are each closed by two plate washers 161.

A bolt 31 is inserted into the plate washer 161 and penetrates the inside of the square steel pipe 16D, and a nut 32 is screwed at a portion where the bolt 31 protrudes. The penetration position of the bolt 31 in the square steel pipe 16D is outside the end plates 12D and 22D, and the end plates 12D and 22D are not formed with holes for inserting bolts.
By connecting the end plates 12D and 22D to each other with bolts 31 and nuts 32, the square steel pipe 16D on the end plate 12D side and the square steel pipe 16D on the end plate 22D side are tightened from the vertical direction, and the vertical rotating pile 10 , 20 are combined.
The protruding dimension of the plate washer 161 in the projecting direction from the pipe bodies 11 and 21 is larger than the protruding dimension of the square steel pipe 16D. A bolt insertion hole is formed at the center of the plate washer 161 in the protruding direction. Therefore, when the square steel pipe 16D and the plate washer 161 are fastened by the bolt 31 and the nut 32, the square steel pipe 16D is fastened at a position offset outward from the center position in the protruding direction.

According to such an embodiment, in addition to the effects described in each of the above-described embodiments, there are the following effects.
A square steel pipe 16D is provided on the outside of the outer periphery of the end plates 12D and 22D, and since the end plates 12D and 22D are joined by bolts 31 and nuts 32 at this portion, holes and the like are processed in the end plates 12D and 22D. The rotary pile joint structure 2D can be constructed without. Therefore, it is possible to reduce the defective portions of the end plates 12D and 22D to improve the strength against the rotational shear force.

Further, since the internal space of the square steel pipe 16D can be secured widely with respect to the diameter of the bolt 31, workability is improved, and even if a rotational shear force acts on the rotary pile joint structure 2D during excavation, the bolt 31 Rotational shear force does not act.
Further, even if a rotational shear force acts on the bolt 31, it acts on the entire inner peripheral surface of the square steel pipe 16D, and the shear load is dispersed, so that the possibility that the bolt 31 is broken by the shear force is reduced. Can be done.

[Sixth Embodiment]
11A to 11C show the rotary pile joint structure 2E of the sixth embodiment of the present invention. 11A is a plan view of the rotary pile joint structure 2E, FIG. 11B is a vertical sectional view taken along line BB of FIG. 11A, and FIG. 11C is a vertical sectional view taken along line CC of FIG. 11A.
In the first embodiment described above, the rotational shearing force acting on the rotary pile joint structure 2 is rotated by forming the engaging holes 13 in the end plates 12 and 22 and inserting the engaging member 33 into the engaging holes 13. It was transmitted from the pile 10 to the rotary pile 20.

On the other hand, in the present embodiment, as shown in FIGS. 11A and 11B, an engaging convex portion 121 is formed on the outer periphery of the end plate 12E, and an engaging concave portion 122 is formed on the end plate 22E, and these are engaged. The difference is that the rotational shear force is transmitted by combining them.
Specifically, as shown in FIG. 11A, the end plate 12E is formed with two engaging protrusions 121 by cutting the end plate 12E along a string connecting two points on an arc of a circular steel plate. ing. The end plate 22E is formed with two engaging recesses 122 that project outward in the circumferential direction in the thickness direction from the string connecting the two points on the circle. The engaging convex portion 121 and the engaging concave portion 122 are formed at positions symmetrical with respect to the circular center of the end plates 12E and 22E. Of course, the forming positions of the engaging convex portion 121 and the engaging concave portion 122 are not limited to this, but the transmission of the rotational shear force is advantageous in a well-balanced manner when they are formed at point-symmetrical positions. Further, a hole 123 for flowing earth and sand is formed in the center of the end plates 12E and 22E.

As shown in FIG. 11B, the bolt holes 16C are 2 at positions deviated by 90 degrees from the forming position of the engaging convex portion 121 of the end plate 12E and the forming position of the engaging concave portion 122 of the end plate 22E about the center of rotation. Bolts 31 are inserted into the respective bolt holes 16C and fastened with nuts 32. The bolt hole 16C is formed as an elongated hole as in the fourth embodiment so that a rotational shear force does not act on the bolt 31 even when the end plate 12G and the end plate 12H are displaced in the rotational direction. It has become.

As shown in FIG. 11C, the engaging convex portion 121 of the end plate 12E can be formed by cutting the circular end plate 12E along the strings described above.
The engaging recess 122 of the end plate 22E can be formed by joining a steel plate to the outer portion of the string described above by welding or the like. Of course, the engaging recess 122 can also be integrally formed by casting using a mold formed in the shape of the end plate 12E.

Even with such an embodiment, it is possible to enjoy the same actions and effects as those described above.
Further, since the uneven engagement is at the outer peripheral end portion of the end plates 12E and 22E, the force against the rotational shear force can be further increased.
Further, by forming the engaging convex portion 121 and the engaging concave portion 122 on the chord connecting the two points on the arcs of the end plates 12E and 22E at point-symmetrical positions, the rotating pile 10 is formed with respect to the rotating pile 20. Can be shifted in the horizontal direction for engagement. Therefore, it is possible to simplify the construction of the rotary pile joint structure 2E.

[7th Embodiment]
12A and 12B show the rotary pile joint structure 2F of the seventh embodiment of the present invention. 12A is a plan view of the rotary pile joint structure 2F, and FIG. 12B is a cross-sectional view taken along the line BB of FIG. 12A.
The rotary pile joint structure 2E of the sixth embodiment described above has an engaging convex portion 121 and an engaging concave portion along a chord connecting two points on the arc of the end plates 12E and 22E at point-symmetrical positions of the end plates 12E and 22E. It was forming 122.
On the other hand, in the present embodiment, the outer peripheral edge of the end plate 12F has a hexagonal shape, and this is used as an engaging convex portion 124, and the end plate 22F has a hexagonal engaging concave portion corresponding to the outer circumference of the hexagon. The difference is that it is 125.

Specifically, as shown in FIG. 12A, the end plate 12F has a regular hexagonal outer peripheral edge, and the entire outer peripheral edge thereof is an engaging convex portion 124. The end plate 22F can be formed by cutting a circular steel plate into a hexagonal shape.
As shown in FIGS. 12A and 12B, the end plate 12F is formed with a hexagonal engaging recess 125 into which the engaging protrusion 124 of the end plate 22F is fitted.
Bolt fastening of the end plate 12F and the end plate 22F is performed by inserting the bolt 31 into the bolt hole 16C formed at a position offset inward from each apex of the hexagon of the engaging convex portion 124 and using the nut 32.

According to such an embodiment, in addition to the actions and effects of each of the above-described embodiments, it is possible to bring the fastening positions of the bolt 31 and the nut 32 to the outer side, and evenly on the vertices of the hexagon. Since the fastening position by the bolt 31 and the nut 32 can be formed, the force against the pulling force acting on the rotary pile joint structure 2F can be balanced by the end plate 12F and the end plate 22F.

[8th Embodiment]
13 and 14 show the rotary pile joint structures 2G and 2H of the eighth embodiment of the present invention.
In the fourth embodiment described above, in the rotary pile joint structure 2C, the rotary piles 10 and 20 are connected by a point-symmetrical engaging hole 13 and an engaging member 33C centered on the rotation center of the rotary piles 10 and 20. It was.
On the other hand, in the rotary pile joint structure 2G of the present embodiment, as shown in FIG. 13, a flat engaging hole 13E is formed in the end plate 12F and the end plate 22F, and the engaging hole 13D has a flat shape. The difference is that the engaging member 33D is used.

Specifically, the engagement hole 13D is formed as an elliptical flat hole having a minor axis L1 and a major axis L2 having different lengths from the rotation center to the inner edge of the rotary piles 10 and 20. In the present embodiment, the angle formed by the short axis L1 and the long axis L2 is set to 90 degrees. The angle formed by the short axis L1 and the long axis L2 does not necessarily have to be 90 degrees and may be 45 degrees or 60 degrees, but the resistance to rotational shear force is most preferably 90 degrees. ..

Further, the flat hole is not limited to an elliptical shape, and as shown in FIG. 14, a flat-shaped engaging hole 13E cut along a chord connecting two points on an arc of a disk-shaped steel plate and the flat hole 13E. An engaging member 33E that engages with the engaging hole 13E may be adopted. Further, the engaging hole may be formed in a rectangular shape, and in short, the engaging hole and the engaging member may be a flat hole having a short axis and a long axis.

Although not shown in FIGS. 13 and 14, the bolts 31 and nuts 32 are fastened on the outer peripheral sides of the pipe bodies 11 and 21 of the end plates 12F, 22F, 12G, and 22G.
Even with such an embodiment, it is possible to enjoy the same actions and effects as those described above.

[Other Embodiments]
The present invention is not limited to the above-described embodiment, and modifications within the range in which the object of the present invention can be achieved are included in the present invention.
In each of the above-described embodiments, the bolts 31 and nuts through which the bolt holes 16 and 16B at the four corners of the end plates 12, 22 or the end plates 12A and 12B are inserted to connect the rotary piles 10 and 20 or the rotary piles 10A and 10B. 32 was used. However, the installation positions and the number of installations of the bolts 31 and nuts 32 are arbitrary and can be changed as appropriate.
Further, instead of the bolt 31 and the nut 32, a member that sandwiches the pair of end plates 12, 22 or the end plates 12A, 12B may be used.

In the first embodiment described above, four engaging holes 13 and 23 are formed in the end plates 12 and 22. However, the number of engaging holes 13 and 23 may be three or less when the required performance of torque transmission is low, and may be five or more when the required performance is high. In any case, it is desirable that the engaging holes 13 and 23 are evenly arranged in the circumferential direction with respect to the centers of the rotary piles 10 and 20.
The engaging holes 13 and 23 are preferably circular holes for rotational processing, but may be a plurality of polygonal holes if they are processed by punching, for example.

In the second embodiment described above, the octagonal engaging hole 13A and the engaging member 33A are used, but they may be hexagonal or quadrangular, for example. As the angle is reduced, the unevenness becomes remarkable and it is effective for torque transmission, but the size that can be arranged on the end plate 12A may become small, and an octagon is preferable in consideration of surface utilization efficiency.

The present invention can be used for rotary pile joint structures.

1 ... pile, 2 ... rotary pile joint structure, 2A ... rotary pile joint structure, 2B ... rotary pile joint structure, 2C ... rotary pile joint structure, 2D ... rotary pile joint structure, 2E ... rotary pile joint structure, 2F ... rotary pile Joint structure, 2G ... rotary pile joint structure, 2H ... rotary pile joint structure, 10 ... rotary pile, 10A ... rotary pile, 10B ... rotary pile, 11 ... pipe, 12 ... end plate, 12A ... end plate, 12B ... end Plate, 12C ... end plate, 12D ... end plate, 12E ... end plate, 12F ... end plate, 12G ... end plate, 12H ... end plate, 13 ... engagement hole, 13A ... engagement hole, 13B ... engagement hole, 13C ... engaging hole, 13D ... engaging hole, 13E ... engaging hole, 14 ... stopper, 14A ... stopper, 14B ... stopper, 15 ... communication hole, 16 ... bolt hole, 16B ... bolt hole, 16C ... bolt hole, 16D ... Square steel pipe, 20 ... Rotating pile, 21 ... Pipe, 22 ... End plate, 22C ... End plate, 22D ... End plate, 22E ... End plate, 22F ... End plate, 22G ... End plate, 23 ... Engagement hole , 24 ... stopper, 31 ... bolt, 32 ... nut, 33 ... engaging member, 33A ... engaging member, 33B ... engaging member, 33C ... engaging member, 33D ... engaging member, 33E ... engaging member, 121 ... Engagement convex portion, 122 ... Engagement concave portion, 123 ... Hole, 124 ... Engagement convex portion, 125 ... Engagement concave portion, 141 ... Recession, 161 ... Plate washer, 331 ... Communication hole, L1 ... Short shaft, L2 ... Long axis.

Claims (12)

A pair of end plates fixed to the ends of the rotating pile,
A rotary pile joint structure provided on one end plate and the other end plate, provided with a shear resistance portion that resists the rotational shear force of the rotary pile. In the rotary pile joint structure according to claim 1,
The shear resistance portion includes an engaging hole penetrating each of the end plates and
A rotary pile joint structure comprising: an engaging member inserted from the engaging hole of one end plate to the engaging hole of the other end plate. In the rotary pile joint structure according to claim 2,
The rotary pile joint structure is characterized in that the engaging hole is a circular hole centered on a position away from the center of rotation of the rotary pile. In the rotary pile joint structure according to claim 3,
A rotary pile joint structure characterized in that a plurality of the circular holes are arranged around the rotation center of the rotary pile. In the rotary pile joint structure according to claim 4,
The rotary pile joint structure is characterized in that the engaging member is a round bar member inserted into the circular hole. In the rotary pile joint structure according to claim 2,
The engaging hole is a polygonal hole concentric with the rotation center of the rotating pile, and the engaging member is a polygonal plate material that can be engaged with the engaging hole. Joint structure. In the rotary pile joint structure according to claim 6,
The rotary pile joint structure, wherein the engaging hole and the engaging member are octagonal. In the rotary pile joint structure according to claim 6,
A rotary pile joint structure in which the engaging hole and the engaging member are hexagonal. In the rotary pile joint structure according to claim 2,
The engaging hole is a flat hole having a minor axis and a long axis having different inner edge lengths from the rotation center of the rotating pile, and the engaging member is a flat shape capable of engaging with the flat hole. Rotating pile joint structure characterized by being a plate material of. In the rotary pile joint structure according to claim 1,
The shear resistance portion has a rotary pile joint structure having an engaging convex portion formed on the outer periphery of one of the end plates and an engaging concave portion formed on the outer periphery of the other end plate. .. In the rotary pile joint structure according to any one of claims 1 to 10.
The end plate is a rectangular plate material having bolt holes at four corners and fixed to the end of the rotary pile, and a pair of end plates are connected to each other by fastening bolts inserted into the bolt holes. Rotating pile joint structure. In the rotary pile joint structure according to any one of claims 1 to 10.
The end plate is a circular plate material having a plurality of bolt holes at positions protruding from the outer peripheral surface of the rotary pile and fixed to the end portion of the rotary pile, and a pair of fastenings is inserted into the bolt holes. A rotary pile joint structure characterized by being connected to each other by bolts.

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