JPS6227539Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a concrete pile whose excess length protruding from the ground surface can be easily cut off after driving at a foundation pile driving site.

Concrete piles are generally used as the foundation of buildings, and these piles are usually driven underground into hard ground, but the required driving depth and pile length must match. In many cases, it is not possible to do so, and it is necessary to cut off the excess protruding portion after driving.

Conventionally, when cutting the head of a concrete pile like this, the protruding part after pouring is broken down with a hammer, or it is cut with a concrete cutter using a rotating disk blade, but both methods generate noise. This caused problems in terms of noise pollution and work efficiency in densely populated areas.

In view of the above-mentioned problems, the purpose of this invention is to provide a concrete pile that can cut the extra length of the head efficiently with less labor and without generating noise. However, spirally wound pipes in which metal bands are spirally wound are embedded in concrete formed in the shape of a solid or hollow cylinder at predetermined intervals in the axial direction and in a direction substantially perpendicular to the axis. Equipped with small diameter holes formed,
By filling the small diameter hole with an expandable crushing agent, it can be freely crushed and cut.

Next, an example of implementation of the present invention will be described with reference to the drawings.

In Figs. 1 and 2, P in the drawings is a concrete pile according to the present invention, and this concrete pile P has a cylindrical gauntlet reinforcement 1 buried inside and a hollow hole 2 in the center, as in the conventional case. At the same time, a tapered portion 3 is integrally formed at the tip.

In the thick part of the concrete pile P, small diameter holes 4a are formed in a direction substantially perpendicular to the axis at regular intervals in the axial direction. This small diameter hole 4a is formed by openings 6, 6' at both ends of the annular sheaths 5a, 5a, . It is formed by burying it facing the outside.

In addition, as shown in FIGS. 3 and 4, in the present invention, a part of the annular sheath 5b having a donut shape is drilled with a small diameter hole in the thick wall part, a small diameter pipe piece 7 is attached by welding, etc., and the opening is opened. The small diameter hole 4b may be formed by embedding the hole 7a facing outward from the side wall surface, or, as shown in FIG. The small diameter hole 4c may be formed by burying the hole facing the wall surface.

Furthermore, as shown in FIGS. 6 to 9, in a solid concrete pile P' or P'',
A small diameter hole 4d formed by substantially spiral annular sheaths 5d, 5d... or an annular sheath 5e formed by connecting large diameter and small diameter donut shaped sheaths with a small diameter pipe 9 and facing outward from the side wall surface. ,5e...
It is also possible to form small diameter holes 4e, 4e, . . . .

Next, a method of using the concrete pile P, P' or P'' constructed as described above will be described.
The concrete pile P, P' or P" having the structure 4c, 4d or 4e is driven into the ground as in the conventional manner for the foundation of a structure, and the pile P, P' or P" is driven into the ground to form a hard foundation.
The small holes 4a, 4b, 4c, 4d or 4e closest to the ground surface (finishing position) of the part of P″ protruding above ground
The expansive crushing agent is filled in the cavity. The expansive crushing agent is a conventionally used material such as a hydrating material mainly made of lime-based inorganic compounds (for example, "Blister" manufactured by Onoda Cement Co., Ltd., "S-Mite" manufactured by Sumitomo Cement Co., Ltd.)
Generally, a slurry containing a mixture of water and kneaded material is added, or a powder is added and then water is added, causing the mixture to harden and expand over time.

Incidentally, thread-cut washers or the like are attached to the inner peripheral surface of the openings at both ends of the annular sheath 5a, 5c, or 5d in advance, and after filling with the expandable crushing agent, the openings are sealed with a plug or the like, or the Appropriate treatment is performed depending on the properties of the crushing agent, such as closing with cement to prevent the crushing agent from flowing out or spewing out from the opening.

By filling the expandable crushing agent in this way, the expandable crushing agent expands over time and the small diameter holes 4
a, 4b, 4c, 4d or 4e, the spiral sheath is expanded in diameter by a component force in the vertical direction to the inner surface, and the pile P, P' or
The concrete in the buried portion of the annular sheath 5a, 5b, 5c, 5d, or 5e of P'' is crushed.
After crushing the concrete, the reinforcing bars exposed to the outside are melted.

The concrete pile of the present invention is constructed and used as described above, and small diameter holes are formed in the concrete pile at predetermined intervals in the axial direction and in a direction substantially perpendicular to the axis. By filling the diameter hole with an expandable crushing agent, the concrete at the cut portion of the pile is crushed, making it less noisy than cutting by conventional mechanical means, and therefore making it easier to use in residential areas, etc. This makes it possible to work at night in densely populated areas, and furthermore, it significantly increases work efficiency.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing a concrete pile as an example of implementing the present invention, and Fig. 2 is an A-A in Fig. 1.
3 and 5 are perspective views and partially cutaway perspective views showing other embodiments of the annular sheath buried in the same pile, FIG. 4 is a cross-sectional view of FIG. 3, and FIG. 6 is a partial vertical sectional view showing another embodiment of the present invention,
7 is a plan view of the same, FIG. 8 is a longitudinal sectional view showing still another embodiment, and FIG. 9 is a sectional view taken along line BB in FIG. 8. P, P′, P″……Concrete pile, 4a,
4b, 4c, 4d, 4e...small diameter hole, 5a, 5
b, 5c, 5d, 5e... annular sheath, 7, 9...
...Small diameter pipe.

Claims (1)

[Scope of utility model registration request] It is formed into a solid or hollow cylindrical shape with concrete, and a spirally wound pipe with a metal band spirally wound is buried in a direction substantially perpendicular to the axis at a predetermined interval in the axial direction. Equipped with small diameter holes formed,
A concrete pile characterized in that the narrow holes are filled with an expandable crushing agent so that the concrete pile can be crushed and cut.