JPH0613769B2 - Slime processing method and equipment for cast-in-place pile driving - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a slime treatment method and apparatus for driving cast-in-place bottom piles used as a foundation of a building.

[Conventional technology]

Conventionally, the slime treatment method at the time of cast-in-place pile is
As described in Japanese Patent Application Laid-Open No. 54-139203, a pile hole 1 is excavated in FIG. 2, a tremie pipe 2 is provided in the pile hole 1, and a blade body 3 is provided at the lower end thereof for slime treatment. 4 was installed with the blade open, and the tremie pipe 2 was rotated to rotate the blade body 3 at the lower end thereof to float the slime 5 at the bottom of the hole in the muddy water and discharge it out of the pile hole 1 by the pumping device. After that, the wing body 3 was closed and pulled up. Further, Japanese Patent Publication No. 54-14842 discloses a slime treatment method in which a tremie pipe obtained by branching a horizontal suction pipe is inserted into an excavation hole, and slime is sucked while rotating the tremie pipe. The conventional slime treatment device for cast-in-place piles is the one described in JP-A-54-139203, that is, the one shown in FIG. 2 attached to the application of this application, which is a tremie tube connected to a rotating device. The bit 4 is integrally fitted to the lower end of the bit 2 so as to rotate and slide up and down, and a plurality of blades 3 are attached to the outer periphery of the bit 4 so that the blade 3 can be opened and closed, and the bit 4 is slid up and down. A weight 7 is fitted so that the wing body 3 and the weight 7 are connected by an opening / closing lever 8 and Japanese Patent Publication No. 55-34248 discloses a slime in which a connecting link is provided between a tremie pipe and a slime suction pipe. A slime processing device is known in which a suction port of a suction pipe is bent and oscillated.

[Problems to be solved by the invention]

According to the conventional slime treatment method for cast-in-place pile, the slime is to be agitated by the wing body of the bit or the horizontal suction pipe of the tremie pipe so as to be suspended in the muddy water. Not only is it inefficient because it cannot remove slime until all the piles are discharged, but expanded piles that expand only the bottom of the piles are often used due to the increase in the diameter of the approximate piles. The breech, lateral suction pipe, or suction port of the slime suction device does not reach the bottom expansion hole of the pile. Therefore, the slime of the bottom hole of the pile hole, which occupies about two-thirds of the pressure receiving area of the pile, is not completely removed. Since concrete is poured from the pipe, concrete in the area where slime is present has the problem that uneven settlement due to compaction condensation cannot be obtained and reliable piles cannot be obtained. According to the slime processing device, the wings are attached to the outer circumference of the bit and the weight is used to open and close the wings with the lever for opening and closing, and the rotation of the tremie tube causes the wings or the horizontal suction pipe or the suction port of the slime suction device to be opened. Since the slime accumulated on the bottom of the hole is stirred or sucked at the same time as the stirring, the slime cannot be removed unless a large amount of muddy water in the pile hole is discharged, which is inefficient. Even if the auxiliary wing 9 is attached to the bottom hole, it can be applied to the large-diameter hole 1'and only the slime at the bottom of the pile hole is removed, or the lateral suction pipe does not reach the large-diameter portion for the bottom-expansion pile and the bottom of the bottom-expansion hole is reached. There was a problem that it was not possible to remove all the slime deposited on the.

[Means for solving problems]

Means of the present invention for solving the above problems is to excavate an upper bottom expanding hole so that the diameter becomes gradually larger below the lower end of the pile hole, and subsequently reduce the diameter to a steep angle to form a hole bottom. The bottom expanding hole is drilled, the tremie pipe that branches the slime suction pipe from the pile hole is inserted, and the slime suction pipe that has expanded to the upper part of the lower bottom expanding hole is contracted while rotating the tremie pipe, A branch pipe is provided below the tremie pipe connected to the slime treatment method and the rotating device at the time of cast-in-place expansion pile driving so that the slime on the entire surface is sucked along the slope, and a flexible pipe is provided at the tip of the pipe. Attach a slime suction pipe whose tip reaches the outer periphery of the upper part of the lower bottom expansion hole that becomes the hole bottom by reducing the lower part of the upper bottom expansion hole to a steep angle with the diameter below the lower end of the pile hole gradually increasing. , Tremy tube and slime sucker A pipe is connected with a pumping device, a weight pipe is vertically movably fitted to the lower end of the tremie pipe, and the slime suction pipe is connected to the weight pipe so that the slime suction pipe moves from above the lower bottom expansion hole along its inclination. It is composed of a slime treatment device for driving cast-in-place expanded bottom piles, which is pivotally connected to a slime suction pipe with a connecting bar.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, a pile hole 11 having an upper bottom expanding hole 10a and a lower bottom expanding hole 10b formed therein is excavated, and the upper part thereof is reinforced by a surface casing 12 to fill muddy water 13, and a tremie pipe 14 is inserted therein.

A swivel joint 15 is provided in the upper part of the tremie pipe 14 and a discharge port 16 is fixed to the swivel joint 15, and a branch pipe 17 is provided in the lower part of the slime suction pipe 1 via a flexible pipe 18.
9 is attached. A weight pipe 20 is vertically movably fitted to the lower end of the tremie pipe 14, and the slime suction pipe 19 and the weight pipe 20 are pivotally connected by a connecting bar 21, and a wire 22 attached to the weight pipe 20 is pulled up. As a result, the slime suction pipe 19 is opened to reach the outer periphery of the upper portion of the lower bottom hole 10b as shown by the solid line, and the weight pipe 20 is lowered by its own weight as shown by the chain line by loosening the wire 22. Since the connecting bar 21 is also lowered, the slime suction pipe 19 is attracted to the tremie pipe 14 and closed so that it does not hinder the pulling up of the tremie pipe 14.

In order to drive expanded bottom piles, in the pile hole 11
3 is temporarily fixed at the upper position of the branch pipe 17, and the tremie pipe 14
Insert. The pumping device is composed of an air pipe 24 and introduces compressed air into the tremie pipe 14 and the branch pipe 17, and as shown by an arrow A, a water flow control valve attached to the end portions of the slime suction pipe 19 and the tremie pipe 14 by an air lift. The muddy water is discharged from the discharge port 16 through 25 as shown by arrow B. Wire 2 for water flow control valve 25
6 is attached, the opening of the water flow adjusting valve 25 is adjusted by pulling up the wire 26, and the amount of muddy water discharged from the tremie pipe 14 is adjusted, and the slime suction pipe 19 and the tremie pipe 14 are adjusted according to the accumulated amount of slime. The amount of slime suction can be adjusted appropriately.

The upper end of the tremie pipe 14 is connected to a rotating device via a swivel joint 15, and the wire 22 is pulled up to expand the slime suction pipe 19 to reach the outer periphery of the upper part of the lower bottom expanding hole 10b. Tremie tube 14
When the wire 22 is loosened while being gently rotated together with the slime suction pipe 19, the weight pipe 20 descends downward by its own weight and is drawn toward the tremie pipe 14 by the connecting bar 21.
7 is sucked from the tips of the slime suction pipe 19 and the tremie pipe 14 without being directly stirred, and the slime 27 accumulated on the bottom of the lower bottom expansion hole 10b is sucked over the entire surface and discharged from the discharge port 16. It The slime 27 can be completely removed by rotating the slime suction pipe 19 about three times. After the slime treatment is completed, the reinforcing bar cage 23 is lowered and fixed to the bottom of the lower bottom expanding hole 10b, the swivel joint 15 at the upper part of the tremie tube 14 is removed, and the tremie hopper 28 is attached to the tremie tube 14 while pouring concrete. Is to be removed.

Although the slime is discharged by the air lift in the above embodiment, it may be discharged by the suction pump. In this case, the air hose 24
Is unnecessary.

〔The invention's effect〕

The method of the present invention does not stir the slime in the muddy water by the blade like the conventional slime treatment method,
The slime suction pipe sequentially sucks and discharges the slime accumulated on the bottom of the lower bottom expansion hole, so it does not diffuse into the mud water, so it is not necessary to discharge a large amount of mud water and the slime can be efficiently discharged. Can be removed, and the slime can be removed over the entire bottom surface of the bottom expansion hole, so the placed concrete can be reliably brought into contact with the support ground, and the slime remained as in the past. It is possible to drive a high-quality and reliable pile without adversely affecting the bearing capacity like a concrete-cast pile.

Further, since the device of the present invention sucks the slime from the slime suction pipe by using the tremie pipe, it is not necessary to discharge a large amount of mud water like the conventional one that stirs the slime and discharges the mud water. Since only the accumulated slime part is sucked, the slime can be removed in a short time by rotating the periphery of the lower bottom expanding hole about 3 times, and the tip of the slime suction pipe reaches the upper outer periphery of the lower bottom expanding hole. Since the tremie pipe can be opened and closed centering on the tremie pipe, only slime accumulated on the bottom surface of the cylindrical drill hole can be processed in the past, but in the device of the present invention, the upper bottom expanding hole is directed downward. Since it is open and the slime sinks downward, it does not deposit, and the lower bottom expanding hole can remove the slime deposited on the bottom surface over the entire surface.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention, and FIG.
The figure is a partial vertical front view showing a conventional example. 10a: upper bottom expanding hole, 10b: lower bottom expanding hole, 11: pile hole, 14: tremie tube, 17: branch tube, 18: flexible tube, 19: slime suction tube, 20: weight Pipes, 21 ... connecting bar, 25 ... water flow control valve, 27 ... slime.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 56-33391 (JP, U) JP 54-14842 (JP, B2) JP 55-34248 (JP, B2) JP 55- 7495 (JP, B2)

Claims (3)

[Claims] 1. A lower bottom expanding hole, which is formed by drilling an upper bottom expanding hole (10a) so that the diameter becomes gradually larger below the lower end of a pile hole (11), and then the diameter is reduced to a steep angle to form a hole bottom. Drilling (10b),
A tremie pipe that branches the slime suction pipe (19) from the pile hole (11)
(14) is inserted, the slime suction pipe (19) expanded to the upper part of the lower bottom expansion hole (10b) is contracted while rotating the tremie pipe (14), and along the slope of the lower bottom expansion hole (10b). A slime treatment method at the time of cast-in-place bottom pile driving so that the slime (27) on the entire surface is sucked. 2. A branch pipe (17) is provided below a tremie pipe (14) to which a rotating device is connected, and its tip is below a lower end of a pile hole (11) via a flexible pipe (18). Install a slime suction pipe (19) that reaches the outer circumference of the upper part of the lower bottom expansion hole (10b) that is the bottom of the hole by reducing the lower part of the upper bottom expansion hole (10a) with a gradually increasing diameter. , A pumping device is connected to the tremie pipe (14) and the slime suction pipe (19), and a weight pipe (20) is vertically movably fitted to the lower end of the tremie pipe (14), so that the slime suction pipe (19) Placed bottomed pile driving, in which the weight pipe (20) and the slime suction pipe (19) are pivotally connected by the connecting bar (21) so that the contracted and closed movement moves from above the lower bottomed hole (10b) along its inclination. Slime processing equipment at time. 3. A slime treatment device for driving a cast-in-place bottom pile according to claim 2, wherein a water flow control valve (25) is provided at the lower end of the weight pipe (20).