JP3719795B2 - Composite joint pile and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
Present invention, the foundation pile, it relates to a concrete and manufacturing method of a composite section pile consisting of a steel plate covering the surface to be used mainly as friction piles.
[0002]
[Prior art]
As the ready-made piles, there are friction piles such as normal piles, steel pipe piles, steel-concrete composite piles, etc., and piles such as node piles that are expected to have a bearing capacity rather than a horizontal bearing capacity.
[0003]
FIG. 4 shows a typical form of the conventional joint pile 11, and many of them are made of hollow prestressed concrete having a joint projection 13 on the outer periphery.
[0004]
The manufacturing method in that case is roughly as follows.
[0005]
{Circle around (1)} Several PC bars 16 are bundled, and the hoop bars 17 are spot-welded to form a reinforcing bar rod.
[0006]
{Circle around (2)} The above-mentioned reinforcing bar is put in a lower mold frame giving a semicircular shape, filled with uncured concrete 15 and centrifugally molded.
[0007]
(3) Steam-cured material is centrifuged in a steam curing tank.
[0008]
{Circle around (4)} Prestress is introduced into the PC reinforcement 16 in order to prevent cracking of the pile concrete 15.
[0009]
Moreover, as a concrete form of a node pile, there exists what was shown, for example in Japanese Patent Publication No.62-53323. The one shown in the same publication has a half-circular shape corresponding to the inside of a half-cylindrical mold frame that can be opened and closed separately, and an inner mold frame that constitutes a node molding part and a body molding part is incorporated. It is a mold, and the inner mold is made of reinforced plastic or the like, the body part is formed thick, and the entire outer periphery is inscribed in the cylindrical mold.
[0010]
[Problems to be solved by the invention]
In the conventional structure of joint piles, in order to prevent cracking of the pile body, the diameter and number of reinforcing bars are changed, and the prestress amount is determined and manufactured. However, the manufacturing process is complicated, such as the placement of PC bars and reinforcing bars, and the introduction of prestress.
[0011]
In particular, in the case of joint piles, it is difficult to reinforce the joint portion, and there is a risk that the joint portion will crack during handling.
[0012]
In addition, joint piles as friction piles usually expect peripheral support rather than horizontal proof stress, and are used for parts where bending does not work much, or usage methods where bending does not work much (for example, multiple ready-made piles) In the case of a lower pile or the like in the case of adding in the longitudinal direction, the bar arrangement may be wasted due to its efficiency.
[0013]
The present invention is intended to solve the above-described problems, and is a composite joint pile having an efficient cross section with a simple structure, easy to manufacture, and having a supporting strength and cracking strength necessary as a joint pile. It is an object of the present invention to provide a method which can be manufactured efficiently and easily .
[0014]
[Means for Solving the Problems]
In the manufacturing method of the composite joint pile according to claim 1 of the present application, the surface of the joint pile having the nodular projections at predetermined intervals in the longitudinal direction is composed of the nodular steel pipe having the nodular projections itself, A method of manufacturing a composite joint pile that forms a hollow joint pile together with concrete integrated on a peripheral surface, and in accordance with the outer peripheral shape of the composite joint pile, the joint protrusions are formed in advance at predetermined intervals. Insert a screw feeder into the knotted steel pipe with one end closed with an end plate and fill it with uncured concrete. After filling the concrete, attach an end plate to the other end. The filled steel pipe is put into a mold of a centrifugal molding apparatus, and the steel pipe and the concrete are integrated by centrifugal molding.
[0015]
The steel plate is mainly for improving the cracking strength of the joint pile concrete portion, and functions as a PC reinforcement or a reinforcement in a conventional concrete joint pile.
[0018]
Centrifugal forming itself can use a method similar to a conventionally performed method, and in that case, the knotted steel pipe can be considered as a discarded frame. The uncured concrete filled in the knotted steel pipe is tightly inserted into the knotted protrusions of the knotted steel pipe by rotating the knotted steel pipe around the axis by a centrifugal molding device, and further integrated with the knotted steel pipe. Can be increased.
[0019]
In addition, for example, the formwork described in Japanese Patent Publication No. 62-53323 described in the section of the prior art is used as it is, the above-mentioned knotted steel pipe is installed in the inside formwork, and the concrete is filled and centrifuged. It is also possible to carry out the process, and it can be easily manufactured using existing equipment.
[0020]
Embodiment
FIG. 1 shows an embodiment of a composite pile pile manufactured by the production method of the present invention. The steel pile is covered with a steel plate covering the surface of the pile pile having nodular projections at predetermined intervals in the longitudinal direction. It is set as 1 node.
[0021]
Surface of the double Gobushikui 1 is constituted by a section with a steel pipe 2 having its own node-like projection 3, together with concrete 5 integrated with the inner peripheral surface thereof, to form a composite clause pile 1 of the hollow . In the figure, reference numeral 4 denotes an end plate made of a steel plate or the like.
[0022]
The knotted steel pipe 2 protects the surface of the concrete 5 and also acts as a PC bar or a reinforcing bar to improve the cracking resistance of the concrete. It is possible to omit the PC reinforcement and the reinforcing bar arrangement that caused the problem.
[0023]
2 and 3 show an embodiment of the method for manufacturing the composite joint pile 1 of FIG. 1, and the composite joint pile 1 can be manufactured by the following procedure.
[0024]
{Circle around (1)} A concrete steel 5 is filled in a knotted steel pipe 2 in which knot projections 3 are formed in advance at predetermined intervals in accordance with the outer peripheral shape of the composite knot pile 1. This filling is performed by a screw feeder 6 having a diameter that can be inserted into the knotted steel pipe 3. The screw feeder 6 is filled with the concrete 5 to some extent and continues to be filled with the concrete 5 while being gradually pulled out, and then the end plate 4 is attached to the other end.
[0025]
(2) The knotted steel pipe 2 filled with the uncured concrete 5 is placed in the mold of the centrifugal molding device 8, and the concrete 5 is centrifugally molded by rotating the mold. In the figure, 7 is a gasket (packing) interposed between the inner surface of the mold of the centrifugal molding device 8 and the knotted steel pipe 2.
[0026]
(3) At the stage where the concrete 5 exhibits some strength, it is removed from the mold of the centrifugal molding device 8 and steam curing is performed.
[0027]
It should be noted that the steel-concrete composite pile in which the concrete 5 and the knotted steel pipe 2 are integrated is formed while the knotted steel pipe 2 is used in a form-removal frame, and the reinforcement of the PC bars and rebars, the pre-stressing to the PC bars. Except that it does not require the introduction of stress, it can be manufactured by the same method with the centrifugal molding device 8 that is almost the same as that for manufacturing conventional piles, and the high-quality composite pile 1 can be produced efficiently. Can do.
[0028]
In addition, as a method of manufacturing the knotted steel pipe 2 used here, a steel plate in which the protrusion of the knot is pressed in advance is sequentially pressed into a U shape and an O shape, for example, as in the U-O-E method. After seam welding, a method of adjusting the shape (you may provide a separate plate if necessary), or a short steel pipe and a ring-shaped steel material that forms a node are connected in series in the longitudinal direction. There are ways to go.
[0031]
【The invention's effect】
(1) The composite joint pile manufactured according to the present invention has a steel plate arranged on the outer peripheral surface of the joint pile. Since the concrete of the protruding portion does not appear on the surface, damage to the node-like protruding portion during handling can be prevented.
[0032]
(2) The composite joint pile manufactured according to the present invention has a function of a PC reinforcing bar or a reinforcing bar as a concrete reinforcing bar in the conventional joint pile. It is possible to omit the steps of knitting the heels, arranging the PC bars, and introducing the pre-stress, thereby reducing the manufacturing cost.
[0033]
(3) The composite joint pile manufactured by the present invention is a steel pipe having a concave and convex shape with a steel plate itself having a nodular projection, and the concrete is filled in the nodular projection, thereby restraining the concrete, Is more reliable.
[0034]
(4) According to the manufacturing method of the present invention, by preparing a knotted steel pipe having knotted protrusions in advance, the knotted steel pipe functions as a discarded frame and can be easily formed by centrifugation. In addition, the steel-concrete composite piles in which the concrete and the knotted steel pipe are integrated are used while the knotted steel pipe is used as a frame, and the pre-stress is introduced into the PC reinforcement and the reinforcement of the reinforcement and the PC reinforcement. Except for the point that is not required, it can be manufactured by the same method with the centrifugal forming apparatus similar to the manufacturing of the conventional node pile, and a high-quality composite node pile can be manufactured efficiently.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a composite joint pile according to the manufacturing method of the present invention, in which (a) is a front view with the middle in the longitudinal direction omitted (the right half is a sectional view), and (b) is its A- It is A sectional view.
FIG. 2 is a cross-sectional view schematically showing a state of filling concrete into a knotted steel pipe in an embodiment of the manufacturing method of the present invention.
FIG. 3 is a cross-sectional view schematically showing a state of centrifugal molding in one embodiment of the manufacturing method of the present invention.
FIG. 4 is a front view (a right half is a cross-sectional view) of an upper part of a joint pile showing a typical form of a conventional joint pile.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Composite nodal pile, 2 ... Nodal steel pipe, 3 ... Nodal protrusion, 4 ... End plate, 5 ... Concrete, 6 ... Screw feeder, 7 ... Gasket, 8 ... Centrifugal molding apparatus,
DESCRIPTION OF SYMBOLS 11 ... Conventional node pile, 13 ... Node-like protrusion, 14 ... End plate, 15 ... Concrete, 16 ... PC reinforcement, 17 ... Hoop reinforcement

Claims (1)

The surface of the nodule with nodular projections at a predetermined interval in the longitudinal direction is composed of a nodular steel pipe with nodular projections itself, forming a hollow nodal pile with concrete integrated on its inner peripheral surface A method for manufacturing a composite joint pile, wherein one end of the composite joint pile is closed with an end plate in a jointed steel pipe in which joint projections are formed in advance at predetermined intervals in accordance with the outer peripheral shape of the composite joint pile . Insert the screw feeder in the state and fill the uncured concrete. After filling the concrete, attach the end plate to the other end, and place the knotted steel pipe filled with the uncured concrete in the mold of the centrifugal molding machine. And manufacturing the composite joint pile characterized by integrating the steel pipe and the concrete by centrifugal molding.

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