JPS59190814A - Manufacture of pile made of hollow concrete - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing hollow concrete ready-made piles,
In particular, the present invention relates to an improved manufacturing method that allows easy construction of hollow concrete ready-made piles with excellent dimensional accuracy in the hollow portion.

Hollow concrete ready-made piles have conventionally been generally manufactured by a casting method using centrifugal force, and casting using stationary formwork has not been put into practical use.

The reason why casting using stationary formwork is not put into practical use is that it is difficult to remove the formwork provided as a core to form the hollow part of the hollow concrete ready-made pile. For example, it is not impossible to cast hollow concrete piles in a stationary form by applying casting technology for large-diameter cylindrical cast steel, but it requires a large amount of materials, labor, and enormous equipment. Therefore, it is not economically profitable.

However, ready-made hollow concrete piles manufactured by a casting method using centrifugal force have the disadvantage that the dimensional accuracy of the hollow portion is poor, resulting in the following problems. In other words, in a structure in which foundation concrete is poured around the top of a pre-made hollow concrete pile that has been driven into the ground, the lower half of a steel pipe is inserted into the hollow part of the pre-made concrete pile to reinforce the horizontal shear resistance. 3. Insert the entire section and bury the upper half of the above steel pipe in the foundation concrete.
(There are often cases where it is desired to use the τ method, but as mentioned above, the dimensions of the hollow part of the pre-made hollow concrete pile) are not good, so it is very difficult to apply the method described in .

The reason for this is that if the inner surface of the cylindrical part of the hollow concrete pile has irregular irregularities, the inner core is bent, or the inner diameter is too small, the steel pipe cannot be inserted. This is because if the inner diameter is too large, the inserted steel pipe will wobble and the above method will not be as effective.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a method for easily manufacturing a hollow concrete 1/ready-made pile with good dimensional accuracy of the hollow part using simple equipment.

In order to achieve all of the above objects, the manufacturing method of the present invention involves inserting a supporting frame into a wound tube-like member having spring elasticity in the direction of reducing the diameter, thereby reducing the IN diameter of the wound tube-like member. Holding the rolled cylindrical member in an expanded state, install the above-mentioned rolled cylindrical member almost concentrically within the cylindrical concrete form, and pour concrete into the cylindrical gap formed between the members of 5) above. After pouring and solidifying 4?L, the support frame is removed, the diameter of the rolled cylindrical part is contracted by the spring elasticity of the member itself, and the member is pulled out.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 (Al is configured to carry out the entire method of the present invention [
This is a partially cutaway drawing of an example of a cylindrical member. This rolled cylindrical member 1 is formed by rolling a spring steel plate into a rolled cylindrical shape, and if it is not possible to apply a separate force from another source, it can be rolled into a state where the diameter is completely reduced as shown in the same figure (Bl). Therefore, in order to maintain the state shown in this figure ( ), an appropriate support member (1 not shown) must be fully inserted into the inside of this rolled cylindrical member 1. The cylindrical member must be supported in a direction that pushes the cylindrical member outward.

As shown in FIG. 1, the wound cylindrical member 1 of this example has a spring elastic force 7 in the direction of reducing its diameter. When carrying out the present invention, the effects described below can be obtained as long as the rolled cylindrical member 1 has a cylindrical shape with spring elasticity, and is not limited to a cylindrical shape as in this example. , can be made into various shapes of cylinders such as elliptical cylinders, polygonal cylinders, etc.8
Also, the edge 1c of the plate formed into a rolled tube shape.

1d may be parallel to the axis as in this example, and S/F
It may be irral-like.

FIG. 2 is a partially cutaway perspective view showing another example 1' of a rolled tubular member constructed for carrying out the entire method of the present invention. This rolled cylindrical member 1' consists of a thin plate 1a made of mild steel and an annular spring 11.
It is wrapped around and fixed to give spring elasticity in the direction of contraction. This figure depicts the state in which the support member 2 (indicated by imaginary line -f) e is inserted so as to enlarge the diameter. When this support member 2 is removed, the rolled cylindrical member 1' is contracted and the diameter is reduced. let

When carrying out the present invention, the same effect can be obtained even if the above-mentioned annular spring [b] is formed into a spiral shape instead of being formed into a monocyclic shape as in this example.

As shown in Fig. 3, a three-metal support frame (described later with reference to Fig. 4) is inserted into the rolled tubular member 1 constructed as described above (with the surface diameter fully extended). Insert 6 pages into the formwork 4 and hold them concentrically.

” 2. A cylindrical space S formed between parts 1 and 4 of both parts.
Fresh concrete 5 is injected into the pile and solidified to form the entire hollow concrete pile (shown with a patch in this figure).

FIG. 4 shows a vertical cross-sectional view of the rolled tubular member 1 in a state where the supporting frame 3 is inserted [7] and expanded as shown in FIG. 3.

The support frame 3 id is shown in an end view in FIG. 3 and a side view in FIG. 4, respectively. In the support frame 3 of this embodiment, a support rod 3c is rotatably attached to a cylindrical support shaft 3a using a hinge 3b.

In the state shown in FIG. 4, the winding tubular member 1 is elastically elastic, and the force arrow f that tends to contract due to the tension is applied to the support rod 3c.
The support 1-1 holds the rolled tubular member 1 in an expanded position.

After the injected ready-mixed concrete 5 solidifies, each support rod 3a' of the support frame 3 (z) is pulled out in the direction of arrow A in Fig. 4.
c('':J-) The tilt saw 5 can be easily pulled out in the direction of arrow B at 17 with the hinge 3b as the center.

When the support frame 3 is pulled out, the rolled tubular member 1 is compressed by the spring elasticity of the rolled tubular member itself, reducing its diameter and peeling off from the inner circumferential surface of the concrete.

In this way, the rolled cylindrical member 1 used as a core in the casting operation can be easily removed from inside the hollow concrete ready-made pile.

The ready-made hollow concrete pile manufactured in this example is cast using the cylindrical member 1 made of steel plate as the core, as explained below, so the dimensional accuracy of the inner surface is high and the The inner surface is smooth3. Therefore, when fitting a steel pipe into this hollow part, it is easy to insert and fit securely, and the hollow concrete ready-made pile and the inserted steel pipe are correctly concentric.For this reason, this The ready-made hollow concrete piles manufactured in accordance with the examples are suitable for use in shear-resistant steel management construction methods and other advanced civil engineering construction methods.

As described in detail, the method for manufacturing a hollow concrete ready-made pile of the present invention involves inserting a supporting frame into a wound cylindrical member having spring elasticity, and adjusting the diameter of the above-mentioned wound cylindrical member. Holding it in an expanded state, the above-mentioned rolled cylindrical member is
19D814 (3) Cylindrical conch! J-1- Installed almost concentrically within the formwork, - After pouring concrete into the cylindrical gap formed between the above two sections and allowing it to solidify, the supporting frame is removed. By contracting the diameter of the rolled cylindrical member by the spring elasticity of the member itself and pulling it out, ready-made hollow concrete piles with high accuracy in the hollow part using the ζ1 method can be easily manufactured using simple equipment. This greatly contributes to improving the quality and reducing costs of prefabricated concrete piles.

[Brief explanation of the drawing]

Fig. 1 shows an example of a rolled cylindrical member configured to carry out the method of the present invention, in which the figure (A+ shows a state in which it has been pushed out to expand its diameter, and the figure (Bl shows a state in which it has been contracted due to spring elasticity). Fig. 2 is a partially cutaway perspective view showing another example of a rolled cylindrical member configured to carry out the method of the present invention. Fig. 3 is an explanation of fresh concrete pouring work. Figures 4 and 4 are explanatory diagrams of the structural functions of the support frame. 1.1'... Rolled tube-shaped member, 1a- Thin plate, 1b... Annular leaf spring, 2... Supporting member, 3.・Support frame, 3a...
Support shaft, page 9 3b... Hinge, 3c... Support rod, 4... Formwork, 5...
- Fresh concrete. Patent Applicant E Wan Quantity Author's Attorney Seven Akimoto Tadashi Jitsu 63- Procedural Amendment (Spontaneous) February 19, 1932 Commissioner of the Patent Office Kazuo Wakasugi 1, Indication of Case 11t I Japanese Patent Application No. 1 .6722 No. 2, Title of the invention A method of using hollow concrete prefabricated piles 3, 1ull fi' with amended person A°1
Patent Applicant Address (Residence) Kita Terao, Tsurumi Ward, Yokohama City, Kanagawa Prefecture / -77-ta Name (Name) Miwa
Quantity: 4, Agent: 5, Date of amendment order: Showa year/month
Day, ゝ-2-4 7. Subject of amendment Detailed description of the invention column 8 in the description
Contents of the amendment As shown in the attached sheet (1) In the specification, in the Detailed Description of the Invention column, page 7, line z, the end of the line ``will be able to do it'' and ``will be able to do it'' at the beginning of the 7th line of the same page.
``In accordance with the present embodiment,'' the statement is added. [As is clear from the above-mentioned actions, the support frame in the present invention is a member that holds the rolled cylindrical member in an expanded position when concrete is poured and is easily removed after the concrete solidifies.] Moreover, any member having the above-mentioned functions is sufficient. In this embodiment, the support rod 3c supported by the hinge 3b
However, the support frame 3 in the present invention is not limited to a structure using hinges as in this example, but the support frame 3 in the present invention is not limited to a structure using a hinge as in this example, but the structure is such that the rolled cylindrical member is held in an expanded position when concrete is poured, Various structures can be considered as members that can be easily removed after concrete solidification. ” Above 65

Claims (1)

[Claims] Insert the support frame into a tubular member with spring elasticity,
−] Maintaining the diameter of the two winding tubular members in an enlarged state (~,
The rolled cylindrical member in the above state was installed almost concentrically within a cylindrical concrete form, and concrete IJ-te was poured into the cylindrical gap formed between the two members and allowed to solidify. A method for manufacturing a ready-made hollow concrete pile, characterized in that the support frame is then removed (the diameter of the rolled cylindrical member is contracted by the spring elasticity of the member itself, and then pulled out from the solidified concrete).