JPH1181304A - Connection structure of steel pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a welding work to connect steel pipes in a construction site and obtain a stable and hight quality of the connected steel pipe, by welding in advance the connection parts of mutual steel pipes in a factory. SOLUTION: Cylindrical connection parts 1, 21 having a smaller outer diameter than steel pipe piles 10, 11 are fixed to the butt ends 10a, 11a of the connecting steel pipe piles 10, 11 and screw holes 3, 23 are formed on the side face of the cylindrical connection parts 1, 21. These connection parts are arranged to butt each other and the outer periphery thereof is covered with a cylindrical joint divided to form arcuate sections and provided with insertion holes for bolts. Respective insertion holes for bolts of the divided cylindrical joint are positioned to correspond to respective screw holes 3, 23 and bolts 12 are inserted in these holes and fastened to connect the steel pipe piles 10, 11. Respective divided cylindrical joints fixed to the cylindrical connection parts 1, 21 and respective bolts 12 are formed not to protrude out of the outer diameter of the connecting steel pipe piles 10, 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure for steel pipes used for piles driven into the ground when constructing a steel tower.

[0002]

2. Description of the Related Art When a steel tower is constructed on a soft ground such as a wetland, a plurality of steel pipe piles are added in an axial direction to a supporting ground in the soil to form a foundation of the steel tower. Conventionally, connection of this steel pipe pile was performed by welding on the spot.

[0003]

However, welding at a construction site is subject to the effects of temperature and wind and rain, and particularly in the case of construction in wetlands, etc., welding is performed in winter when the ground on which heavy equipment can be carried is frozen. Preheating management is difficult and takes time and effort. In some cases, welders with poor technical skills may work,
Furthermore, if the pile driving work is interrupted for a long time, the ground closes and the pile cannot be driven after that. In these cases, sufficient nondestructive inspection cannot be performed, and there is a problem in the quality of the welded portion.

The present invention has been made in view of the above points, and a cylindrical connecting portion is welded in advance to an end portion of a steel pipe in a factory, and such a steel pipe is carried to a site, and a steel pipe pile is welded. Use as When connecting the steel pipes, the butted portion of the cylindrical connection portion provided on the steel pipe is covered from the outside of the pipe with a divided cylindrical joint, and then the connection is performed by fastening with bolts, and such connection is performed. The problem is solved by providing a structure.

[0005]

According to the first aspect of the present invention, a cylindrical connecting portion having an outer diameter smaller than the diameter of the steel pipe is coaxially connected to and fixed to a butt end of each steel pipe to be connected.
A number of screw holes are provided on the side surface of the cylindrical connecting portion, and these cylindrical connecting portions connected and fixed to each steel pipe are butted against each other, and the outer periphery of the two butted cylindrical connecting portions is formed in an arc shape. Each divided piece is covered with a divided cylindrical joint in which a number of bolt insertion holes are drilled, and each bolt insertion hole of the divided cylindrical joint and each screw hole of the cylindrical connection portion are aligned. The steel pipes are connected to each other by screwing the bolt ends into the screw holes and tightening the bolt ends by passing the bolts through the bolt insertion holes, and the divided cylindrical joints fixed to the cylindrical connection portion and the heads of the tightened bolts Is a steel pipe connection structure which does not protrude beyond the outer diameter of the steel pipe to be connected.

According to a second aspect of the present invention, a cylindrical connecting portion having an outer diameter smaller than the diameter of the steel pipe is coaxially connected to and fixed to a butt end of each steel pipe to be connected. Provide a number of screw holes and annular irregularities on the outer circumference on the side,
These cylindrical connection parts connected and fixed to each steel pipe are butted against each other, the outer periphery of the two butted cylindrical connection parts is appropriately divided into an arc shape, and a number of bolt insertion holes and Cover with a split cylindrical joint provided with an annular uneven portion on the back surface, fit the annular uneven portion provided on each of the cylindrical connecting portion and the split cylindrical joint, fit each bolt insertion hole of the split cylindrical joint and Align each screw hole of the cylindrical connection part, pass a bolt through these bolt insertion holes, screw the bolt end into the screw hole, tighten and connect the steel pipes, and each divided cylinder fixed to the cylindrical connection part The joint of the steel pipe and the head of each of the bolts tightened are steel pipe connecting structures that do not protrude beyond the outer diameter of the steel pipe to be connected.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. First, a cylindrical connecting portion 1 provided at an edge portion of a steel pipe pile will be described with reference to FIGS. 1 to 3. The outer diameter of the end 1a of the cylindrical connecting portion 1 connected to the steel pipe pile is smaller than the inner diameter of the connected steel pipe pile, and the cylindrical connecting portion follows the end 1a. An annular protrusion 2 is provided on the side surface of the cylindrical connecting portion 1 so that the cylindrical connecting portion 1 is engaged with the steel pipe pile end when the fixed length 1 is fitted to the steel pipe pile end. As shown in FIG. 1, the outer diameter of the annular convex portion 2 is made equal to the outer diameter of the steel pipe pile to reduce the resistance in the soil.

The cylindrical connecting portion 1 following the annular projecting portion 2
Has an outer diameter which is smaller than the outer diameter of the steel pipe pile. At this point, twelve threaded holes 3 are formed annularly at equal intervals. Each of these screw holes 3 is internally threaded. In addition, the side surface of the cylindrical connecting portion 1 following these screw holes 3 is provided with an annular concave and convex so that the split cylindrical joint is locked to the cylindrical connecting portion 1 when covered by a later-described divided cylindrical joint. A part 4 is provided. Further, the strength of the cylindrical connecting portion 1 is reinforced by these annular uneven portions 4.

The shape of the cylindrical connecting portion is different from that shown in FIG.
There is another type as shown in FIG.
1 is different from the cylindrical connecting portion 1 only in the shape of an edge 21b on the side opposite to the side provided on the steel pipe pile. That is, when these two cylindrical connecting portions 1 and 21 are abutted, the edge 1b of one cylindrical connecting portion 1 is fitted into the edge 21b of the other cylindrical shape 21. , Cylindrical connection 1
Has a tapered cross section.
The edge 21b of the other cylindrical connecting portion 21 is the edge 1
It is configured to accept b. And edge 2
1a, the annular convex portion 22, the screw hole 23, and the annular concave and convex portion 24 have the same shape as the cylindrical connecting portion 1. These cylindrical connecting portions 1 and 21 are provided with cross-shaped ribs 5 and 25 on the inner side, respectively, for reinforcement of strength.

FIGS. 5 and 6 show one of the four divided pieces 6a of the divided cylindrical joint 6 of the present invention. Bolt insertion holes 7 for bolt insertion penetrating from the front side to the back side are formed in the upper and lower three pieces at equal intervals in the divided piece 6a. Is located at the approximate center of the substantially semicircular step 8 which is one step lower than the surface of the bolt, to reinforce the strength of the divided piece 6a and to hide the head of the bolt when the bolt is tightened to avoid contact with other objects. The resistance is as low as possible. As shown in FIG. 1, the cylindrical connecting portion 1 is provided on the back side of the divided piece 6a.
Corresponding to the annular concave and convex portions 4 and 24 provided on the outer surfaces of the first and the second concave portions, the concave and convex portions 9 are provided so as to be fitted to them. Also, when the split piece 6a is fixed to the outside of the cylindrical connecting portions 1 and 21 as the split cylindrical joint 6,
The outer diameter is the same as the outer diameter of the steel pipe pile, and each of the uneven portions 9 is configured to form an annular uneven portion.

Next, a procedure for connecting the steel pipe piles 10 and 11 using the cylindrical connecting portion 1 and the divided cylindrical joint 6 will be described. In a factory or the like, one end 1a of the cylindrical connecting portion 1 is connected to the end 10a of one steel pipe pile 10 to be connected, and the cylindrical connecting portion 21 is connected to the end 11a of the other steel pipe pile 11 to be connected. One of the edge portions 21a is fitted with each other, and then they are fixed by welding. These steel pipe piles 10, 11
Is brought into a construction site, and the steel pipe pile 10 is driven into the soil with the cylindrical connecting portion 1 not fixed first.

When the driving progresses and a stage for connecting a new steel pipe pile 11 is reached, the end 1b of the cylindrical connection portion 1 welded to the tail of the steel pipe pile 10 is replaced with a cylindrical pipe provided on another steel pipe pile 11. It fits into the edge 21b of the connection part 21. Then, according to the shape of the annular concave and convex portions 4, 24 of the cylindrical connecting portions 1, 21 and the screw holes 3 and 23, four divided pieces 6a are applied and tightened through the bolts 12, and the two steel pipe piles 10, 1
1 is connected. Thereby, the two steel pipe piles 10 and 11 are firmly connected.

Further, the steel pipe pile 1 connected in this manner is
The stress of the connecting portions 0 and 11 is provided on the contact surface between the cylindrical connecting portions 1 and 21 against the compressive force, and is provided on the outer surface of the cylindrical connecting portions 1 and 21 against the tensile force. Shearing of the uneven portions 4 and 24 and the uneven portion 9 provided on the back surface of the divided piece 6a;
Since the stress at the point where the maximum stress is applied against the bearing force and the bending force is the same as that of the compression and tension forces, it resists by the same mechanism as the compression and tension forces, In this case, the shearing force is resisted by the uneven portion of the contact surface between the cylindrical connecting portions 1 and 21. Further, the bolt 12 prevents the cylindrical connecting portions 1 and 21 and the split piece 6a from coming off, and resists eccentric bending caused by a tensile force. Therefore, it is stable and strong in terms of strength. Further, even after the divided cylindrical joint 6 is fixed to the cylindrical connecting portions 1 and 21, the divided cylindrical joint 6 does not protrude outside the circumference of the steel pipe piles 10 and 11. In this case, the resistance is low.

When connecting the steel pipe piles with the joints, various things such as transmitting the stress from the upper pile to the lower pile reliably, withstanding the impact at the time of pile driving, and further preventing the steel pipe pile itself from bending into a square shape. However, according to the present invention, as described above, these requirements can be satisfied, and the work can be performed quickly and easily, and the quality of the connected portion can be stabilized. .

Although the above embodiment is used for connecting steel pipe piles, the present invention is not limited to steel pipe piles, but can be widely used for connecting steel pipes. The screw holes 3 and 23 of the cylindrical connecting portions 1 and 21 are penetrated, but this is not an essential requirement of the present invention. In addition, these screw holes 3, 2
3 may be a through hole, a nut may be provided on the circumferential surface of the cylindrical connecting portions 1 and 21, and each bolt insertion hole 7 of the divided cylindrical joint 6 may be a threaded hole with an internal thread. . Although the two cylindrical connecting portions 1 and 21 have different edge portions 1b and 21b so that they can be fitted when the two cylindrical connecting portions 1 and 21 are abutted, this is not an essential requirement of the present invention. Further, the side surfaces of the cylindrical connecting portions 1 and 21 and the divided cylindrical joint 6
Are provided on the back surface of the substrate, respectively, but there are cases where these are not provided. Furthermore, a cylindrical joint obtained by dividing a cylindrical joint into four parts was used as a dividing band.
It is not limited to division.

[0016]

According to the first aspect of the present invention, a steel pipe pile with a cylindrical connection welded in a factory or the like is brought into a construction site and used, so that welding work at the construction site is not required. In addition, since the welding operation is performed at a factory or the like, the nondestructive inspection can be sufficiently performed at the factory or the like. Therefore, stable and high quality products can be obtained. Also, since there is no welding work at the site, no complicated work involved in the welding work at the site is required.

According to the second aspect of the invention, in addition to the effect of the first aspect, the annular concave and convex portions provided on each of the cylindrical connecting portion and the divided cylindrical joint are fitted, so that the divided cylindrical portion is formed. Shaped joints can be securely and firmly connected. Also, the strength of the connecting portion is strong and reliable because the respective concave and convex portions are fitted.

As a result, the steel pipe pile driving work can be performed more easily and quickly on site than in the past, and the strength of the steel pipe pile after construction is stable and reliable. Things.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a state where steel pipe piles according to an embodiment of the present invention are connected.

FIG. 2 is a front view of a cylindrical connecting portion according to the embodiment of the present invention.

FIG. 3 is a plan view of a cylindrical connecting portion according to the embodiment of the present invention.

FIG. 4 is a front view of another type of cylindrical connecting portion in the embodiment of the present invention.

FIG. 5 is a front view of a divided piece obtained by equally dividing the divided cylindrical joint in the embodiment of the present invention into four parts.

FIG. 6 is a sectional view taken along line AA in FIG.

FIG. 7 is an external view of an embodiment of the present invention.

FIG. 8 is a sectional view taken along line BB in FIG. 7;

[Explanation of symbols]

1,21 Cylindrical connection part 3,23
Screw holes 4, 24 Annular irregularities 6
Split cylindrical joint 6a Split piece 7
Bolt insertion hole 10, 11 Steel pipe 10a,
11a Edge 12 Bolt

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuhiro Yoshida 1-1-1 Shinjuku, Shinjuku-ku, Tokyo Nasu Electric Machinery Co., Ltd.

Claims (2)

[Claims] 1. A cylindrical connecting part having an outer diameter smaller than the diameter of the steel pipe is coaxially connected to and fixed to a butt end of each steel pipe to be connected, and a number of screws are provided on a side surface of the cylindrical connecting part. A hole is provided, and these cylindrical connecting portions connected and fixed to each steel pipe are butted against each other, and the outer periphery of the two butted cylindrical connecting portions is appropriately divided in an arc shape. Cover with a split cylindrical joint with a bolt insertion hole,
The steel pipes are connected to each other by aligning each bolt insertion hole of the split cylindrical joint with each screw hole of the cylindrical connection portion, passing bolts through these bolt insertion holes, screwing bolt ends into the screw holes, and tightening. The joint structure of steel pipes, wherein each of the divided cylindrical joints fixed to the cylindrical connection part and the heads of the tightened bolts do not project beyond the outer diameter of the steel pipe to be connected. 2. A cylindrical connecting part having an outer diameter smaller than the diameter of the steel pipe is coaxially connected to and fixed to a butt end of each steel pipe to be connected. The screw hole and the annular uneven portion are provided, and these cylindrical connection portions connected to each steel pipe and fixed are butted against each other, and the outer periphery of the two butted cylindrical connection portions is appropriately divided into an arc shape, Each divided piece is covered with a number of bolt insertion holes and a divided cylindrical joint provided with an annular uneven portion on the back surface, and the annular uneven portion provided on each of the cylindrical connecting portion and the divided cylindrical joint is fitted. Align each bolt insertion hole of the split cylindrical joint and each screw hole of the cylindrical connection part, pass a bolt through these bolt insertion holes, screw the bolt ends into the screw holes and tighten them to connect the steel pipes to each other. Each cylindrical joint fixed to the joint And the head of the bolt is tightened is characterized in that so as not to protrude from the outer diameter of the steel pipe to the connection, the connection structure of the steel pipe.