JPS5944422A - Pile drawing work and casing and extended casing for excavation of annular pit therefor - Google Patents

Abstract

PURPOSE:To make easier the drawing of piles by a method in which an excavating blade is provided to the lower end of the opening of a cylinder having an inside diameter larger than the outside diameter of an underground pile, and the ground is excavated by a casing with a spiral blade for discharging excavated soil on the outside of the cylinder. CONSTITUTION:The hollow of a casing 1 for excavating an annular pit is positioned above an underground pile 18, and while turning the casing 1, an excavating liquid is supplied through the liquid supply path 17b of a driver 17 and discharged to near the excavating blade 3 from an outlet port 5a. Whereupon, the excavating liquid is injected into soil to give the soil a fluidity and also to make the discharge of the soil by a spiral blade 4 easier. The rotary output unit 17a of the driver 17 is removed from the casing 1, a wire 19 is hooked on the head of the underground pile 18, and the underground pile 18 is pulled up by a crane provided to a leader 16.

Description

[Detailed description of the invention] The present invention relates to a construction method for pulling out piles from underground.

Conventionally, the pile extraction method involves destroying underground piles with a rock excavator.
Since this is a method of pulling up residual debris underground, it requires a lot of effort to pull up the debris and post-treatment of the debris, and it also takes a lot of time to transport a large rock excavator to and from the pile extraction site. It had the disadvantage of requiring time and effort.

One object of the present invention is to provide an extremely novel and useful method for extracting piles by excavating the outer periphery of an underground pile in an annular manner to the depth of the tip of the pile and pulling the pile without destroying it. The present invention also aims to provide a casing for use in this new construction method.

The present invention will be described below based on drawings showing embodiments thereof. Annular hole drilling casing 1 used in the pile extraction method according to the present invention (hereinafter referred to as the present invention method)
As shown in FIG. 1, the lower end 2a of the cylinder 2 has upper and lower openings.
Excavation blades 3, 3, etc. are fixed at appropriate pitches by welding or the like, and spiral blades 4 for excavated soil discharge are fixed at appropriate lead pitches on the outer surface 2b of the cylinder 2 by welding or the like. Further, a discharge port 5a of a liquid feed pipe 5 which is piped along the lower surface side of the spiral blade 4 is opened in the vicinity of the excavation blade 3. A detachable connector 50 attached to the flexible tube 5b is provided at the upper end of the liquid feeding tube 5. The cylindrical body 2 has an appropriate number of recesses 6a of the joint 6 in an inverted shape on the upper edge of the outer periphery. Since the length of the annular hole drilling casing 1 is limited due to transportation and workability, when a long length is required, an appropriate number of annular hole drilling extension casings 7 as shown in FIG. 2 are connected. Ru. The annular hole excavation extension casing 7 has an inverted hook portion 6b extending vertically from the lower end of the vertically opened cylinder 2 so as to correspond to the recess 6a of the annular hole excavation casing 1. At the same time, a recess 6a is provided on the upper edge of the outer periphery in the same manner as described above. Further, the annular hole excavation extension casing 7 is provided with a spiral blade 4' for discharging excavated soil on the outer surface zb of the cylinder 2, and a liquid supply pipe 5 is installed on the lower surface side of the spiral blade 4'. has been done. When the annular hole drilling extension casing 7 is connected to the annular hole drilling extension casing 1 and when the annular hole drilling extension casings 7 are connected, the 4 (4') end surfaces of the vertically adjacent spiral blades face each other. The positions of the recess 6a and the hook 6b of the joint 6 are determined so that the helical blades approach each other and become continuous. Furthermore, detachable connectors 50 attached to flexible tubes 5'b are attached to both ends of the liquid feed pipe 5' that runs along the lower surface of the spiral blade 4'. One method for connecting the joint 6 is to insert the hook portion 6b into the recess 6a from above, rotate the hook portion 6b toward the tip of the hook, and then hit a knock in the appropriate place to prevent reverse rotation. and connect. Although not shown, another method for forming the recess 6a and the hook 6b of the joint 6 is to form the cylindrical body 2.2' (2) to be connected.
An annular step is formed on one outer circumferential surface of the abutting end of the abutting ends of ``, 2''), and an annular inner step is formed on the inner circumferential surface of the other end in a fitting relationship with the annular step. There is a method in which either the recess 6a or the hook 6b is provided on the inner and outer circumferential surfaces forming the annular inner and outer stepped portions. By the way, the joint 6 is not limited to the illustrated embodiment in any way, and it is of course possible to adopt any suitable type of joint.

Next, the construction method of the present invention using the annular hole drilling casing 1 shown in FIG. 1 will be explained below based on FIG. 3. In the first step of the present invention, as shown in FIG. 3(A), the hook part 6b of the rotation output part 17a of the drive device 17, which is provided on the leader 16 of the crane vehicle so as to be movable up and down, is used for drilling the annular hole. While connecting the four parts 6a of the casing 1,
The inlet of the liquid feed pipe 5 is connected to the liquid feed path 17b provided in the rotation output part 17a (not shown), and the hollow part of the annular hole drilling casing 1 is located above the underground pile 18. It hangs down on the ground surface GL like this. Next, as a second step, while rotating the annular hole drilling casing 1, a drilling fluid such as bentonite aqueous solution supplied from an external fluid supply pump (not shown) is supplied to the drive device 17.
It is supplied to the liquid feeding pipe 5 through the liquid feeding path 17b, and is discharged from the discharge port 5a of the liquid feeding pipe 5 to the vicinity of the excavating blades 3, 3, . The excavating liquid supplied to the vicinity of the excavating blades 3, 3, . . . is mixed into the excavated soil, imparts fluidity to the excavated soil, facilitates the discharge of the soil by the spiral blades 4, and maintains stable excavation. When the total length of the casing 1 for annular hole excavation is shorter than the underground pile 18, when the upper end of the casing 1 for annular hole excavation comes close to the ground surface, the casing 7 for extending annular hole excavation (second
(see figure), and continue digging to the depth of the tip of the underground pile 18.

As the excavation progresses, an annular excavated hole 23 (see FIG. 3(B)) is formed on the outer periphery of the underground pile 18. Judgment 6 - Whether or not the underground pile 18 has been excavated to the depth of the tip is determined by the length of the annular hole excavation casing 1 and the annular hole excavation extension casing 7, if the length of the underground pile 18 is known. You can find out from here. However, if the length of the underground pile 18 is not known, the excavation blade 3°3...
When the underground pile 18 reaches the tip of the annular hole drilling casing 1. This is determined from the phenomenon of rotation due to the annular hole excavation extension casing 7 or the sinking phenomenon of the underground pile 18 that occurs when the excavation blade 3 excavates deeper than the tip of the underground pile 18. As a third step, the rotation output part 17a of the drive device 11 is removed from the casing 1 for annular hole excavation after drilling, and the head of the pile 18 located near the upper end inside the casing 1 for annular hole excavation with the upper end open. Put wire 19 on,
A crane device (not shown) provided on the leader 16 pulls up the underground pile 18 as shown in FIG. 3(C). If the underground pile 18 is longer than the hanging length of the crane, the entire underground pile 18 is pulled out by cutting it each time the underground pile 18 is pulled up a predetermined length. If it is not possible to hang the wire 19 on the head of the pile 18, a hook 24 as shown in FIGS. 4 and 5 is inserted into the hollow hole 18a of the pile 18, and the hook The hook 24 pulls up the pile 18 by its action. The hook 24 has a gap 31 formed by connecting the upper and lower ends of the vertically long side plates 25 and 25, and hook plates 26 and 27 of different lengths are provided in the gap 31 to connect the side plates 2 to each other.
It is pivoted 28.29 eccentrically at 5.25. The lower end of the hook 24 is formed into a pointed end for easy insertion, and the wire 19 is connected to the upper end via a wire connector 30.

The operating wire 21 is connected to the claw plate 26, 27 near the tip opposite to the pivot side. After the hook 24 configured in this manner is suspended on the stake 18, the hook plate 26 and 27 are inserted into the hollow hole 18a of the stake 18 while operating the operating wire 21 with the respective claw plates 26 and 27 in a vertically elongated state. Loosen the operating wire 21 and remove both claws 27a of the claw plate 27.

27b is brought into contact with the inner peripheral wall of the pile 18. When the wire 19 is subsequently pulled up, the hook 24 causes the claw portion 27a to largely bite into the inner circumferential wall using the principle of leverage, and pulls up the pile 18. In the illustrated embodiment, the claw plate 27 digs in, but if the hollow hole of the pile 18 is large, the long claw plate 28 digs into the inner peripheral wall. In the fourth step, as shown in FIG. 3-7-(D), the annular hole excavation casing 1. The annular hole excavation extension casing 7 is pulled upward while rotating or without rotating. Note that the remaining holes 22 are filled if necessary.

As detailed above, the present invention excavates the minimum necessary annular hole in the outer periphery of the underground pile and pulls out the underground pile in its original form.
Piles can be removed in a shorter time than before. Furthermore, since excavation is carried out while supplying drilling fluid to the vicinity of the excavation blade, the excavated soil can be easily discharged and the excavation power can be reduced, making it extremely possible to contribute to the development of pile extraction method technology. . Further, the annular hole drilling casing and the annular hole extension casing according to the present invention have the advantage that the liquid supply pipe is installed on the lower surface side of the spiral blade, so that the drilling fluid can be easily supplied to the vicinity of the drilling blade. .

[Brief explanation of the drawing]

The drawings are all for explaining the present invention in detail, and FIG. 1(A) is a plan view of a casing for drilling an annular hole according to the present invention, and FIG. 1(B) is a front view of 8-same as above. , Figure (C) is a bottom view of the same as above, Figure 2 (A
) is a plan view of the annular excavation extension casing according to the present invention, FIG. 3(B) is a front view with the middle omitted from the same as above, FIG. A simplified sectional view for explaining the present invention in detail, FIG. 4 is an explanatory view showing a method for pulling out an underground pile using a hooking tool, and FIG. 5 is a v--
It is a v-line cross-sectional view. 1...Casing for circular hole drilling 2(z)...Cylinder 3...Drilling blade 4(4')...Spiral blade 5
(5)...Liquid feed pipe 6...Joint 7...Casing for extension of circular hole drilling Patent applicant: Moroki -Yoshiro, Patent attorney, Toshihiko Uchida, Fig. 2, 6 (6a), JP-A-1982- 44422 (4) Figure 1 Figure 5 Figure 4 (■

Claims (1)

[Claims] 1. In the drilling method, an excavation blade is provided at the lower end of the opening of a cylindrical body formed with an inner diameter slightly larger than the outer diameter of the underground pile, and a cutting blade is provided on the outer surface of the cylindrical body. a first step of supporting an annular hole drilling casing equipped with a spiral blade for discharging excavated soil onto the ground surface so that the hollow part of the casing is positioned above the underground pile; A second step of excavating the outer periphery of the underground pile in an annular manner to the depth of the tip of the pile while supplying the liquid to the vicinity of the excavation blade through a feeding path provided in the casing, and pulling out the underground pile from the upper end opening of the casing. The third step of raising the
A pile extraction method characterized in that the fourth step of pulling out the casing remaining underground due to the excavation is performed in this order. 1-2. In the annular hole excavation casing, a cutting blade is provided at the lower end of the opening of the cylindrical body, and a spiral blade for discharging excavated soil is provided on the outer surface of the cylindrical body, and further along the lower surface side of the spiral blade. 1. A casing for drilling an annular hole, characterized in that a discharge port of a liquid feeding pipe is opened in the vicinity of the drilling blade. 3. In the extension casing for annular hole excavation, joints are provided at the upper and lower ends of the opening of the cylindrical body, and a spiral blade for discharging excavated soil is provided on the outer surface of the cylindrical body. An extension casing for drilling annular holes, characterized by having a liquid pipe installed.