JPH10140565A - Embedding method of steel pipe pile and steel pipe pile used for it - Google Patents

Abstract

(57) [Abstract] [Problem] To economically bury steel pipe piles in the ground where obstacles such as boulders exist. SOLUTION: A reinforcing band 3 is fixed to a lower end portion of a steel pipe pile 1 and a plurality of cut grooves 5 are provided. At the lower end of the steel pipe pile 1, a drill bit 5, which is formed by projecting a disengagement body 7 from a base plate 6 having a tool 8 on the lower surface, is attached by engaging an engaging piece 7 a of the cutting groove 4. The wire 10 is bound to 7b. The steel pipe pile 1 is rotationally press-fitted. In the intermediate layer having obstacles, while the boulders and the like are crushed by a drill bit, the obstacles that have entered the steel pipe pile 1 are removed with a hammer club or the like, and the casting proceeds.
After passing through the intermediate layer, the wire 10 is pulled, the drill bit 5 is detached from the steel pipe pile 1, and the wire is lifted and collected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for burying steel pipe piles in the ground where obstacles such as boulders and gravel exist in an intermediate layer, and to a steel pipe pile used for the method.

[0002]

2. Description of the Related Art When burying steel pipe piles in the ground, if there is an intermediate layer such as boulders or gravel on the ground, removal work of boulders or gravel is performed prior to construction of the steel pipe piles. .
Conventionally, a pre-boring method, an all-casing method, or the like is used for this removal operation. In particular, in order to remove large obstacles such as boulders, all-turn construction machines are often used. After these removal operations, the ground is replaced with sand or the like, and then the steel pipe piles are buried.

There is also a construction method in which a ready-made pile and a casing are buried at the same time, which is described in, for example, JP-A-56-81718. Furthermore, there is also a construction method in which a drill bit is attached to the steel pipe pile itself.
No. 32 discloses this.

[0004]

However, in the above-mentioned conventional method of removing the intermediate layer, a construction process using a construction machine different from the pile driving is involved, and both the construction period and the construction cost are increased. However, it is extremely uneconomical, especially when using a full-rotation type construction machine, the excavation diameter becomes excessively larger than the pile diameter, the amount of removed soil increases, and the ground around the pile is disturbed more than necessary, There is a drawback that loosening has an adverse effect on surrounding structures.

In the method using an auger rod, it is impossible to penetrate the auger rod with a large obstacle such as a boulder. In addition, when the casing is used, the surrounding ground is loosened due to the pull-out, and a construction machine having a sufficient capacity for a frictional force with the ground is required. In addition, when a drill bit is attached to the pile itself, an expensive bit is buried and uneconomical.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional method, and the work involved in removing the intermediate layer can be directly buried in a steel pipe pile by a pile construction machine. To provide a method of burying steel pipe piles and a steel pipe pile to be used for this method, which enables economical construction and minimizes disturbance (looseness) of the ground around the piles It is.

[0007]

The construction of the present invention for achieving the above object will be described with reference to the drawings corresponding to the embodiments. A drill bit 5 that can be attached and detached and collected is provided in the section, and the steel pipe pile 1 is rotationally pressed into the intermediate layer (a) where obstacles such as boulders and gravel are present. The steel pipe pile 1 is rotationally press-fitted by crushing or pushing the obstacle to the side, and when reaching the lower end of the intermediate layer (a), the obstacle entering the steel pipe pile 1 is removed, and the intermediate layer (a).
After excavation, the drill bit 5 is recovered and the steel pipe pile 1 is buried to a predetermined depth.

Further, the steel pipe pile according to claim 2 is a steel pipe pile main pipe.
A plurality of cut grooves 4 each having a required depth are provided at intervals in the circumferential direction at the tip of the main pipe 2, and the cut grooves 4 are joined to the lower end face of the main pipe 2 and provided with the cutting tool 8. An excavation bit 5 having an operating piece 7 having an engaging piece 7a capable of engaging and disengaging from the notch groove 4 is formed, and a wire 10 for pulling up the excavation bit 5 engaged with the notch groove 4 is connected to the excavation bit 5. It is characterized by wearing.

[0009]

Embodiments of the present invention will be described below. 1A to 1E show an embodiment of the method of the present invention in the order of steps, and FIGS. 3 to 7 show examples of a steel pipe pile used in the method. .

First, a steel pipe pile used in the method of the present invention will be described. Referring to FIGS. 3 to 7, reference numeral 1 denotes a steel pipe pile buried in the ground, and the outer circumference of the lower end of the main pipe 2 has a required height. A reinforcement band 3 is applied. The main pipe 2 and the reinforcing band 3 are provided with a plurality of cut grooves 4 having a required depth (height) from the lower ends thereof at intervals in the circumferential direction of the pipe. Is formed on the inclined surface 4a whose outer peripheral side is higher.

A drill bit 5 is detachably mounted in each of the cut grooves 4. Drill bit 5
The base plate 6 has a width from the inner periphery of the main pipe 2 to slightly outside the outer periphery of the reinforcing band 3 and is formed in an arc shape having a required length along the circumferential direction of the steel pipe pile 1 and a central upper surface thereof. The engagement piece 7a inserted into the cut groove 4 and the cut groove 4
An engaging / disengaging body 7 formed in an L-shape with the operation piece 7b projecting upward is provided upright. A plurality of tools 8 each having a chip 9 are provided on the lower surface of the substrate 6, and a hole 7 c is provided inside an upper portion of the operation piece 7 b. Wire 10 is bound.

As shown in FIG. 3, each excavating bit 5 inserts the engaging piece 7a of the engaging and disengaging body 7 into the cut groove 4 of the steel pipe pile 1 and attaches the operating portion 7b to the inner periphery of the main pipe 2. At the same time, the substrate 6 is engaged with the steel pipe pile 1 by contacting the lower end surface of the steel pipe pile 1. Then, by pulling the wire 10, as shown in FIG. 7, the interlocking piece 7 a escapes from the cut groove 4, and the drill bit 5 can be pulled up inside the steel pipe pile by the wire 10. In the illustrated example, the number of the excavating bits 5 is four, but the number may be more than six, eight, or the like.

The method of the present invention is performed using the steel pipe pile 1 described above. As shown in FIGS. 3 and 4, the steel pipe pile 1 is erected at a predetermined position on the ground with the excavation bits 5 and 5 attached thereto, as shown in FIGS. 1
Press into the ground while rotating. The steel pipe pile 1 eventually reaches the intermediate layer (a) 1 in which boulders, gravel, and the like are present, as shown in FIG.

In the intermediate layer (a) 1, the construction proceeds to the lower end of the intermediate layer (a) while the drill bits 5, 5 crush or push the boulders or the like to the side by the rotary press-fitting of the steel pipe pile 1. Become. At this time, if it is difficult to press-fit the steel pipe pile 1, as shown in FIG.
Remove obstacles such as gravel. In this case, it is preferable to remove the obstacle in advance to a position slightly deeper than the excavation bit 5.

When the steel pipe pile 1 has passed through the intermediate layer (a) and reached the lower layer (b) thereunder, obstacles in the steel pipe pile 1 are removed by a hammer grab, a rock auger, or the like. As shown in (c), the press-fitting of the steel pipe pile 1 is temporarily stopped, and the wire 10 attached to each excavation bit 5 is pulled by an operation from the ground. Thereby, as shown in FIG. 7, the excavation bit 5 goes around the inside of the main pipe 2, so that the connecting piece 7 a comes out of the cut groove 4 and separates the lower end of the steel pipe pile 1. . Then, the wire 10 is pulled up, and the drill bit 5 is collected out of the steel pipe pile 1.

After the excavation bit 5 is collected, as shown in FIG. 1- (d), the excavation auger 12 is inserted into the steel pipe pile 1 by a general excavation method or a percussion method.
As shown in FIG. 1- (b), the steel pipe pile 1 is made to reach a predetermined depth, for example, a support layer (C), and a final impact is applied to complete the embedding. In this case, as shown in FIG. 2, a solidified lump 13 may be provided at the lower end of the steel pipe pile 1.

[0017]

As described above, according to the present invention,
The same construction machine will be able to drive piles and remove obstacles such as boulders and gravel in the ground. Therefore, the site, the construction period, and the construction cost are reduced, and the construction can be performed extremely economically without requiring special machines. Further, since the steel pipe pile in contact with the ground is not pulled out, disturbance (looseness) of the surrounding ground can be minimized. Further, the drill bit is economical because it can be collected and used multiple times, and the cost can be improved by using a more expensive high-strength material for the bit. .

Further, the steel pipe pile and the drill bit have a simple structure and are easy to manufacture, so that the work of removing and collecting the drill bit can be easily performed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view sequentially showing an embodiment of the present invention in (a) to (e).

FIG. 2 is a longitudinal sectional view showing another example of the final step.

FIG. 3 is a longitudinal sectional view showing a main part of an embodiment of a steel pipe pile used in the method of the present invention.

FIG. 4 is a bottom view of the same.

FIG. 5 is a longitudinal sectional view showing a main part of a steel pipe pile and a drill bit separately.

FIG. 6 is a side view of the same.

FIG. 7 is an explanatory view showing a state in which a drill bit is detached and raised.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel pipe pile 2 Main pipe 3 Reinforcement band 4 Cut groove 5 Drilling bit 6 Substrate 7 Disengagement body 7a Engagement piece 7b Operation piece 8 Tool 10 Wire 11 Hammaglab 12 Drilling auger

Claims (2)

[Claims] At the tip of a steel pipe pile to be buried, an excavation bit capable of being detached and collected is provided, and the steel pipe pile is rotationally press-fitted. In an intermediate layer where obstacles such as boulders and gravel are present, The obstacle was crushed or pushed to the side by the drill bit, and the inside of the steel pipe pile was rotationally press-fitted.When the bottom of the intermediate layer was reached, the obstacle inside the steel pipe pile was removed and the intermediate layer was bent. After that, the drilling bit is collected and the steel pipe pile is buried to a predetermined depth. 2. An excavating tool, which is provided with a plurality of cut grooves having a required depth at circumferential intervals at a tip end of a steel pipe pile main pipe, and is joined to a lower end face of the main pipe. A drill bit having an operating piece having an engaging piece capable of being disengaged from the cut groove is formed on the substrate, and a wire for pulling up the drill bit engaged with the cut groove is bound to the drill bit. Characterized by a steel pipe pile.