JP2615097B2 - Formwork for the production of knotted PC piles - Google Patents

Description

Description: TECHNICAL FIELD The present invention manufactures a knotted PC pile (prestressed concrete pile) by filling concrete in a cylindrical form, rotating the form and centrifugally forming the form. The present invention relates to a concrete pile manufacturing formwork.

[Background Art] Conventionally, when forming a PC pile by centrifugal molding, a mold 1 '
As shown in FIGS. 9A and 9B, the mold half is formed of a half-cylindrical half mold half 1a ', 1b' divided into upper and lower parts, and one half of the half mold half 1a 'is removed and the other half is formed. The core reinforced cage 2 is placed in the mold half 1b 'and concrete is filled, and one mold half 1a' is put on the mold half 1b ', and both the mold halves 1b'
a ', 1b' are fastened by the flange 4 and both ends of the form 1 'are closed by end plates 5a, 5b, tension is applied to the core bar 2 and high-speed rotation is applied to the form 1'. Centrifugal molding. However, there is a knot forming recess 6 'on the inner surface of the mold halves 1a and 1b for the mold 1' for manufacturing a knotted PC pile.
When the C pile is formed, the joint forming recess 6 'of the mold 1' and the PC
There is a problem in that a portion that firmly adheres to the knot of the pile is formed, making it difficult to remove the mold. In general, when manufacturing a PC pile, a predetermined tension is applied to the core reinforced cage 2 in a state in which the concrete is filled in the formwork (the reaction force of the tension is caused by the end plates 5a, 5).
b), the tension applied to the mold 1 'is released after consolidation molding of the PC pile, that is, at the time of demolding, and tension is introduced into the PC pile. The pile is about to shrink, while the mold 1 'is tightly adhered at the nodes to try to stretch.

[Objects of the Invention] The present invention has been made in view of the above description, and an object of the present invention is to mold a PC pile, and to form a node forming recess of a mold frame and a node of a PC pile. An object of the present invention is to provide a formwork for manufacturing a knitted PC pile, which can be easily removed from the mold without increasing adhesion.

DISCLOSURE OF THE INVENTION The mold for manufacturing a knitted PC pile of the present invention is formed in a cylindrical shape by combining semi-cylindrical mold halves, and a knot-forming recess provided at a position where a knot is formed has a rubber-like elastic body. It is characterized by being made elastically movable in the longitudinal direction of the mold half by a resilient portion comprising the above-mentioned structure, and has solved the drawbacks of the conventional example by the above-described configuration. In other words, after the knot forming recess provided at the position where the knot is formed is elastically movable in the longitudinal direction of the mold half by the elastic portion made of a rubber-like elastic body, the knot is formed by applying tension, and then tension is applied. Even if the force is released, even if the node of the PC pile moves in the longitudinal direction of the PC pile, the knot forming recess moves due to the elasticity of the elastic elastic part and the node does not strongly adhere, and the PC pile after forming Has become easier.

 Hereinafter, the present invention will be described in detail with reference to examples.

As shown in FIG. 1 and FIG. 2, a form 1 (hereinafter referred to as a form) for manufacturing a knitted PC pile is substantially cylindrical and has two upper and lower mold halves 1a, 1b divided into two in the circumferential direction. Is formed. Each of the mold halves 1a and 1b has a double pipe structure composed of an outer pipe 8 and an inner pipe 9 made of metal. Flanges 4 are provided on both sides in the circumferential direction of the half frames 1a and 1b in the longitudinal direction, and the flanges 4 are fastened to each other with bolts and nuts to be assembled. This flange 4 is an outer tube 8
FIG. 1 (a).
As shown in (b), a window 20 for fastening bolts and nuts to the outer tube 8 is provided. The flange 4 may be protruded outward from the outer tube 8 so that the flange 4 can be fastened with bolts and nuts. In the mold halves 1a and 1b, elastic portions 10 extending in the circumferential direction are buried at equal intervals in the longitudinal direction. This elastic part 10 is formed of a rubber-like elastic body,
The pile 11 is provided at intervals for forming nodes. This elastic part
The outer periphery of 10 is supported by the outer tube 8 and is exposed to the inner surface side from the inner tube 9. The rubber-like elastic body which becomes the elastic portion 10 is rubber,
It is a synthetic resin, a thin metal plate or the like. The inner tube 9 is supported by the outer tube 8 by a rib or the like. This elastic portion 10 has a knot forming recess 6.
Are formed, and the node of the PC pile 11 is formed by the node forming concave portion 6. Also, tires 12 are mounted on the mold halves 1a and 1b at equal intervals in the longitudinal direction and in the circumferential direction. End plates 5a and 5b are provided at both ends in the longitudinal direction of the mold 1, and a core bar 2 is arranged inside the mold 1 as shown in FIG. The main rebar cage 2 has a plurality of core rebars 2 arranged in the longitudinal direction and at intervals in the circumferential direction.
Hoop rebar 2b coiled around 2a and main rebar 2a
It is composed of End iron plate 13 at both ends in form 1
Are arranged, and both ends of the main reinforcing bar 2a of the cored reinforcing bar cage 2 are inserted into the end iron plate 13. One end of the main reinforcing bar 7a is connected to one end plate 5a by screw connection, and the other end of the main reinforcing bar 7a is connected to a sliding plate 14 arranged at the other end in the mold 1 by screw connection. Connected. A screw shaft 15 protrudes from the sliding plate 14, and the screw shaft 15
15 is inserted into the end plate 5b, and a nut 16 is screwed to the screw shaft 15. The device for rotating and driving the mold 1 is formed by providing a drive roller 19 on a drive shaft 18 driven by a motor 17. The drive rollers 19 are provided at the same interval as the tires 12 of the mold 1. Thus, the molding of the PC pile 11 is performed as follows. With the upper mold half 1a removed as shown in FIG. 4, the remaining mold half 1b is set on the base 21, and the mold 1b
The core material reinforced basket 2 is set therein, and in this state, the concrete 3 is dropped from the charging machine (hopper) 22 and the concrete 3 is charged into the mold half 1b from the upper opening. At this time, guides 23 are arranged on both sides of the upper opening of the mold half 1b so that the concrete 3 does not spill. Next, the mold half 1 is put on and the flanges 4 are connected to each other to assemble the mold 1, the mold 1 is set on the drive roller 19, and the nut 15 is tightened to apply a tension to the core bar 2. Next, the drive shaft 13 is driven to rotate the mold 1 to perform centrifugal molding. When the PC pile 11 is formed after curing by centrifugal molding, the nut 16 is loosened to release the tension. At this time, the PC pile 11 contracts in the direction of arrow A in FIG. 3, and the mold 1 extends in the direction of arrow B in FIG. Next, the mold half 1a is removed, and the PC pile 11 in the mold half 1b is suspended upward by a vacuum lifter to release the PC pile 11. At this time, even if the PC pile 11 shrinks, the node is easily removed by the elastic deformation of the elastic portion 10 having elasticity of the node, and the demolding is smoothly performed. Such demolding may be reversed and demolded as shown in FIG.

Next, the embodiment shown in FIG. 7 will be described. Formwork halves 1a, 1b
Inside is a separate metal plate 21 that is circumferentially spaced at equal intervals in the longitudinal direction.
The metal plate 21 has a knot forming recess 6 formed in the circumferential direction. Both sides of this metal plate 21 and the mold half
An elastic part 10 made of a rubber-like elastic body is interposed between the metal plates 21 and 1a and 1b, and the metal plate 21 is connected to the mold halves 1a and 1b via the elastic part 10. Also in the case of this embodiment, the PC pile 11 can be easily pulled out when the node forming recess 6 can move in the longitudinal direction of the mold halves 1a and 1b due to the elastic displacement of the elastic portion 10 and the mold is removed.

In the above embodiment, the flanges 4 on both sides of the upper and lower mold halves 1a and 1b are connected by bolts and nuts. However, the flanges 4 on one side may be connected to each other by hinges so as to be freely opened and closed.

[Effects of the Invention] In the present invention, as described above, the node forming concave portion provided at the position where the node is formed is elastically movable in the longitudinal direction of the mold half by an elastic portion made of a rubber-like elastic body. Under tension
After molding the PC pile, release the tension to reduce the knot of the PC pile.
Even if it moves in the longitudinal direction of the PC pile, the knot forming concave part can move due to the elastic displacement of the elastic part which is elastic, and the knot does not adhere tightly as before, making it easy to remove the PC pile after molding You can do it.

[Brief description of the drawings]

1 (a) and 1 (b) are front and side sectional views of one embodiment of the present invention, and FIG. 1 (c) is a side sectional view of another example of the above embodiment.
Fig. 3 is a partially omitted plan view of the above, Fig. 3 is a plan sectional view of the same state in which the core rebar is arranged, Fig. 4 is a side sectional view of the same state where concrete is poured, and Fig. 5 is the same. FIG. 6 is a side sectional view showing another example of taking out the PC pile of the above, and FIG. 7 is a partially omitted plan view of another embodiment of the same. 1 (a) and 1 (b) are a side sectional view and a plan view of a conventional example, in which 1 is a mold, 1a and 1b are mold halves, 6 is a knotted concave portion, and 10 is an elastic portion.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masao Yoshimi 2--20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Inside the Takechi Corporation (72) Inventor Mitsumasa Oikawa 2--20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Takechi Corporation In-house (72) Inventor Ide Daikoku 2-20-20 Koraibashi, Higashi-ku, Osaka-shi, Osaka Inside Takechi Corporation

Claims (3)

(57) [Claims] A knot-forming recess formed in a cylindrical shape by combining semi-cylindrical mold halves, and provided at a position where a node is formed, is an elastic portion made of a rubber-like elastic body, and is a longitudinal portion of the mold half. A formwork for manufacturing a knitted PC pile characterized by being elastically movable in the direction. 2. An elastic portion made of a rubber-like elastic body is provided on an inner surface of a mold half at a position where a node is formed, and a node forming recess is formed in the elastic portion. The formwork for manufacturing a knitted PC pile according to claim 1. 3. A metal plate separate from the mold half is disposed on the inner surface of the mold half at a position where the node is formed, and a knot forming recess is provided in the metal plate. 2. The production of a knotted PC pile according to claim 1, wherein the metal plate is connected to the mold half with an elastic portion made of a rubber-like elastic body interposed between the mold half. Formwork.