JPH10140568A - Embedment method of steel pipe pile or the like and excavation casing for steel pipe pile or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bury economically a steel pipe pile into the ground where there exists an obstacle, such as a boulder stone. SOLUTION: A plurality of cut grooves are provided at the tip of a cylinder- shaped casing main pipe 2 which is insertible into a steel pipe pile and an excavation bit 6 having a tool 10 on the bottom is provided removably and tiltably into the cut grooves in uniformity with each cut groove, thereby forming an embedment method of a steel pipe pile or the like. The steel pipe pile is outwardly inserted into the excavation casing A while the excavation casing A is turningly pressed thereinto so that the excavation may proceed. After having completed excavation work of the ground where there exists an obstacle, such as a boulder stone, the excavation casing A is pulled out. Then the steel pipe pile is driven to a specified depth after having removed the boulder stone in the steel pipe pile.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art When burying steel pipe piles or steel sheet piles (hereinafter referred to as steel pipe piles) in the ground, if there is an intermediate layer such as boulders or gravel on the ground, prior to the construction of the steel pipe piles, etc. Removal work of rocks, gravel, etc. is performed. 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 or the like 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. Further, there is also a gazette in which a drill bit is attached to the steel pipe pile itself, and this construction method is disclosed in, for example, Japanese Utility Model Laid-Open No. 04-77632.

[0004]

However, in the above-described conventional method of removing the intermediate layer, a construction process using a construction machine different from the driving of piles and the like 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 larger than the pile diameter, the removed soil becomes large, and the ground around the pile is disturbed more than necessary. Has the disadvantage of loosening and adversely affecting the 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, if the drill bit is attached to the pile itself, it is expensive and the 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 performed by directly burying a steel pipe pile or the like with a pile construction machine. To provide a construction method for burying steel pipe piles and the like and an excavating casing used for the same, so that construction can be performed economically and disturbance (looseness) of the ground around the piles can be minimized. Is what you do.

[0007]

The construction of the present invention for achieving the above object will be described with reference to the drawings corresponding to the embodiments. The excavating bit A is formed by tilting the excavating bit 6 from the position protruding outward from the casing to the position in which it hangs down, and a steel pipe pile 1 buried in the casing is extrapolated. After rotating the drilling and carrying out the excavation, the steel pipe piles 1 are taken along, and after excavating the intermediate layer where obstacles such as boulders and gravel are present, the drilling casing A is pulled out and the steel pipe piles 1 It is characterized in that the obstacles contained therein are removed, and thereafter, the steel pipe piles 1 and the like are driven to a predetermined depth.

In the excavating casing of the present invention, a plurality of cut grooves 4 having a required depth are provided at a distal end portion of the cylindrical casing main pipe 2 at intervals in a circumferential direction. In response to the above, the excavation bit 6 that can be tilted freely from the excavation position, which engages with the cut groove 4 and protrudes to the outside of the casing, to the hanging position, is suspended in the distal end portion of the casing main pipe 2. It is a feature.

[0009]

Embodiments of the present invention will be described below. 1A to 1C sequentially show an embodiment of the construction method of the present invention, and FIGS. 2 to 6 show one embodiment of a drilling casing used in the construction method.

First, in the method of the present invention, a description will be given of a drilling casing used by being inserted into a steel pipe pile or steel sheet pile to be buried. In FIGS. A drilling casing formed of a steel pipe having a diameter rotatably inserted therein. A reinforcing band 3 covering a required height is attached to an outer periphery of a lower end portion of the main pipe 2, and a required depth (height) is provided from the lower end. ) Are provided at intervals in the circumferential direction of the tube. Further, brackets 5 and 5 for attaching a drilling bit 6 described later are protrudingly provided on the inner surface of the pipe corresponding to a position above each cut groove 4.

The drill bit 6 has a width considerably larger than the thickness (width) of the lower end surface of the casing main pipe 2 and has a base 7 formed in an arc shape having a required length along the pipe circumferential direction. An L-shaped engaging body 8 is provided on the upper surface of the central portion and is engaged with and disengaged from the cut groove 4. On the lower surface of the substrate 7, a plurality of tools 10 provided with the chips 9 are spaced.

As shown in FIG. 2, each excavation bit 6
The horizontal part of the engaging body 8 is inserted into the cut groove 4, the upright part is attached to the inside of the casing main pipe 2, the upper end thereof is pivotally connected 11 to the bracket 5, and the substrate 7 is attached to the casing main pipe 2.
2 and 3 is provided so as to be tiltable from the position shown in FIGS. 2 and 3 where the outer peripheral portion protrudes outward from the reinforcing band to the hanging position as shown in FIG. In the illustrated example, the number of the excavating bits 6 is four, but the number may be more than six, eight, or the like.

In the method of the present invention, the above-described excavating casing
Use A. Explaining the embedding of a steel pipe pile as an example, first, as shown in FIG. 2, the excavating casing A is engaged with the excavating bit 6 so that the horizontal portion of the engaging body 8 engages with the cut groove 4 and the substrate 7 is The excavating casing A is placed upright at a predetermined position on the ground in a state of contact with the lower end surface. And FIG.
-As shown in (a), a steel pipe pile 1 to be buried is fitted outside the excavation casing A. In addition, drilling casing A
At the upper end, a casing gripper 12 is attached, and is connected and suspended via its rod to an auger motor 13 provided on a yagler (not shown) so as to be able to move up and down.

In the above state, the auger motor 13 is operated to reduce the rotational pressure of the excavating casing 2. As a result, ground excavation by the excavation bits 6 and 6 is performed, and the excavation casing A proceeds with subsidence. In this case, the steel pipe pile 1 follows the settlement of the drilling casing A, but it is preferable that the lower end thereof does not contact the drilling bit 6.

As the excavation and settlement proceeds, the excavation casing A reaches the intermediate layer (a) where obstacles such as boulders and gravel are present. In the intermediate layer (a), as shown in FIG. 1- (a), the drill bit 6 crushes rocks and gravel under the lower end face of the drilling casing A and the steel pipe pile, etc., and the construction proceeds, and the rocks and gravel etc. Part enters the excavation casing A.

As shown in FIG. 1- (b), when the excavating casing A has finished excavating the intermediate layer (a) and has reached the lower layer (b) thereunder, the auger motor 12 is raised and excavated. Pull up casing A. At this time, each excavation bit 6 engaged with the cut groove 4 is disengaged from the cut groove 4 and hangs around the pivot point 11 as shown in FIG. As a result, there is no possibility that the lifting will be hindered. Then, the excavating casing A is pulled out from the steel pipe pile 1, and the steel pipe pile 1 is left in the ground.

After the excavating casing A is pulled out, FIG.
(C) As shown in FIG.
4 and other obstacles such as boulders and gravel that have entered the steel pipe pile 1 are removed. When the removal of the obstacles is completed, the steel pipe pile 1 is moved to a predetermined depth by a general construction method such as a digging method or a hitting method, in which a drilling auger is inserted into the steel pipe pile 1 or the like, although not shown. For example, the construction is completed by reaching a strong support layer, applying a final impact, or providing a solidified nodule at the lower end of the steel pipe pile 1.

The method of the present invention is not limited to the burying of the steel pipe pile as described above in order not to rotate the members such as the steel pipe pile to be buried, and the steel sheet pile having the joint member provided outside the steel pipe. It can also be applied to burial.

[0019]

As described above, according to the present invention,
The installation of steel pipe piles and steel sheet piles and the removal of obstacles such as boulders and gravel in the ground can be performed without inserting the drilling casing and rotating the pile itself. It can be done very economically, and the site, construction period and construction cost are reduced. Also, since the drill bit protrudes outward from the casing and can be drilled larger than the pile diameter,
While excavation is in progress, there is little effect on the steel pipe pile, etc., and the drill bit hangs down inside the casing, so the drill casing can be placed inside the steel pipe pile for construction, and the drill casing can be pulled up easily and smoothly Can be done. Further, since the steel pipe pile or the like in contact with the ground is not pulled out, disturbance (looseness) of the surrounding ground can be minimized.

Further, the excavating casing has a simple structure and is easy to manufacture, and can be used repeatedly, so that the cost can be further reduced. Further, since the member itself such as a steel pipe pile to be buried is not rotated, it can be used for burying a steel pipe sheet pile having a joint member outside the pile body.

[Brief description of the drawings]

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

FIG. 2 is a vertical sectional view showing a main part of an embodiment of a drilling casing used in the method of the present invention.

FIG. 3 is a bottom view of the same.

FIG. 4 is a vertical sectional view showing a drill bit separated from a casing.

FIG. 5 is a side view of the same.

FIG. 6 is an explanatory view of a state when the excavating casing is pulled up.

[Explanation of symbols]

 Reference Signs List A drilling casing 1 steel pipe pile 2 casing main pipe 3 reinforcing strip 4 cutting groove 5 bracket 6 drilling bit 7 substrate 8 engaging body 10 tool 11 pivoting point 13 auger motor 14 hammer club

Claims (2)

[Claims] 1. A drilling casing is formed in a distal end portion of a cylindrical casing main pipe so as to be tiltable from a position protruding outward from the casing to a position hanging down, and a steel pipe to be embedded in the casing is formed. Extrapolate piles, rotate the excavation casing, carry out excavation and carry steel pipe piles, etc.After finishing excavation of the intermediate layer where obstacles such as boulders and gravel are present, pull out the excavation casing , Remove the above obstacles in steel pipe piles, etc.
Characterized by driving steel pipe piles etc. to a predetermined depth,
Burial method for steel pipe piles. 2. A plurality of cut grooves having a required depth are provided at intervals in a circumferential direction at a distal end portion of a cylindrical casing main pipe, and a front end of the casing main pipe is provided corresponding to each of the cut grooves. An excavating casing for burying steel pipe piles or the like, wherein an excavating bit that can be tilted freely from a digging posture that engages with a cut groove and protrudes to the outside of the casing and hangs down is suspended in the portion.