JPS6198821A - Method of pulling off hollow concrete pile - Google Patents

Abstract

PURPOSE:To facilitate pulling-off of a pile, by a method wherein a pile wall is crushed while a crusher being suspended into an existing hollow concrete pile, is intermittently lifted up to a given position from the tip end of the pile, and after the crusher is removed, a steel wire protruding from the upper tip of the pile is pulled. CONSTITUTION:A crusher 4 is suspended in a hollow part 3 of a hollow concrete pile 2 driven in a ground 1 by means of a wire rope 5. The crusher 4 is intermittently lifted up from a position in the vicinity of the forward end of the hollow part 3 to a given position at the upper part, and the crusher 4 is actuated at each stop position to crush a pile wall 2a. After the crusher 4 is removed from the hollow part 3, a wire rope 6 is connected to a steel wire or a steel rod 2b protruding from the upper end of the pile 2 by means of a coupling tool 7. Further, the wire rope 6 is pulled with the aid of a crane and the like to pull of the pile 2 for removal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a construction method for pulling out existing hollow concrete piles.

[Technology of craftsmanship]

Bifurono-Nmae method is known as a construction method for pulling out existing central concrete piles. Bifro・
・The Nmae method is a construction method in which a pie float hammer, which is a type of vibrator, is used to apply vertical vibration to the pile, reduce the weight of surrounding machinets, etc., and then pull out the clay pile.

[Problems to be Solved by the Invention] In the case of the pipe hammer method described above, there are problems such as the generation of dog-like photography and noise, and there are also problems such as the need for a crane with a large lifting capacity.

[Means for solving problems]

In order to solve the above problems, the present invention suspends a crusher in the hollow part of an existing hollow concrete pile, and works the crusher while manually pulling the crusher from the tip of the pile to a predetermined position. 9 Destroy the pile walls one by one and take out the crusher from inside the hollow part.
After that, there is a straight steel wire protruding from the top of the Song Ni concrete pile.

A hollow concrete shaft is constructed by using cement as a connecting tool.

[For production]

Since the destruction of the pile wall of the hollow concrete pile is carried out by a crushing device suspended in the hollow part, there is no generation of large noise or vibration, and the frictional force between the hollow concrete pile and the surrounding ground is reduced.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 and FIG. 2 are side sectional views showing the breaking process and the pulling process, respectively, of the drawing method according to the present invention.

In order to pull out a hollow concrete pile 2 such as a 7'v PC pile after being driven into the ground L in the figure, first, as shown in FIG.
is suspended using a wire rope 5, a crane, etc. (not shown), and the crusher 4 is intermittently operated from the vicinity of the tip of the pile in the hollow part 3 to a predetermined position above, for example, over the area where the pile is tightly bound at the bottom. The pile wall 2a is pulled up and the crusher 4 is operated at each stop position to destroy the pile wall 2a.

By destroying the pile wall 2a, the frictional force between the surrounding ground l and the hollow concrete pile 2 is significantly reduced.

The crusher 4 is taken out from inside the hollow part 3, and as shown in Figure 2, a wire rope 6 is connected to the steel wire or steel bar 2b protruding from the upper end of the hollow concrete pile 2 using a connector 7.
Thereafter, the wire row 16 is pulled by a crane or the like (not shown), and the hollow concrete pile 2 is pulled out and removed.

In addition, there are multiple failure points in the circumferential direction of the pile wall 2a of the hollow concrete pile 2, and the failure range in the longitudinal direction of the pile wall 2a is not limited to the length from the pile tip to a predetermined position, but extends over the entire length. Of course, that's fine.

Figure 3 shows the pile wall 2a of the hollow concrete pile 2 in the hollow part 3.
This is a front view of the crusher 4, which is destroyed from the inside.

In the figure, a support 8 has a pair of arms 10 with a bit 9 attached to the outside of the lower end, and the upper ends of each arm 10 are pivoted to a bottle 11.
In order to hang the arm support 8 by the wire rope 5, two hanging fittings 12 and 13 are attached so as to be swingable in two directions perpendicular to each other. Hydraulic jack 14fl, '/' that opens and closes the lower ends of a pair of arms lO
) arm support 8 by center 14 a f bin 15
The ram 14b is connected to each arm 10 using a trouble link 16.
When hydraulic oil is supplied and discharged to 8 and the ram 14b is retracted, the lower ends of the pair of arms IO are opened by the trouble link 16.
Further, when the ram 14b is projected, the lower ends of the pair of arms 10 are closed, and the pile 9.2a of the hollow concrete pile 2 is destroyed by the bit 9 by the action of the arm lOO.

Figure 4 shows hollow concrete piles 2 and 5 respectively.
2A and 2B are a front view and a plan view showing a good state in which a connecting tool 7 which protrudes from the upper end of the FC steel wire or steel rod 2b and connects the wire rope 6 is attached to the steel wire or steel rod 2b.

In the figure, a rectangular rigid plate 18 forming a part of the connector 7 has a plurality of copper wires protruding from the upper end of the hollow concrete pile 2.
Alternatively, the rod 2b is inserted through the rigid plate 18, and the male cone 19a>is attached to the female cone 19b to the copper wire or steel rod 2b protruding from the rigid plate 18. A hanging fitting 20 to which the wire rope 6 is attached is fixed to the central part of.

〔Effect of the invention〕

As described above, according to the present invention, noise and vibration can be significantly reduced compared to the conventional technology, and since the load of the bipronominal, etc. is not loaded on the crane, etc., the size of the crane, etc. can be reduced. This has effects such as being able to reduce the force required for pulling out.

[Brief explanation of the drawing]

Figure 1 is a side sectional view showing the breaking process and pulling process of the pulling method according to the present invention, Figure 3 is a front view of the crusher, Figure 4 is a front view of the crusher, Each figure is a front view and a plan view showing how the connector is attached to the steel wire, etc. ■...Ground 2...Hollow concrete pile 2a...
・Pile wall 2b... Steel wire has 4 needles 3... Hollow part 4... Crusher 5, 6... Wire port -
7... Connector Applicant Hazama Co., Ltd. Figure 1
Figure 2

Claims (1)

[Claims] A crusher is suspended in the hollow part of an existing hollow concrete pile, and the pile wall is sequentially destroyed by the crusher while being intermittently pulled up from the tip of the pile to a predetermined position, and the crusher is taken out from inside the hollow part. A hollow concrete pile extraction method in which a steel wire or steel rod protruding from the upper end of the hollow concrete pile is pulled out using a connecting tool.