JP2628009B2 - Cutting method of existing underground anchor material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cutting an existing underground anchor material.

[0002]

2. Description of the Related Art An anchor method is widely used for excavating a ground in a surrounding ridge. This is a construction method in which the retaining wall is supported by an anchor material fixed in the ground as shown in FIG. If this anchor material is not removed and remains in the ground, if you try to construct a new retaining wall or cast-in-place pile from above, the anchor material will be entangled with the blade of the excavator and the construction will be impossible There are cases. In such a case, the existing underground anchor material was conventionally removed by the following method. <B> Drill a shaft from the ground to the anchor burial position. A method in which an operator descends into the hole to gas-cut the anchor material. <B> A method in which holes are drilled from the ground with an auger machine and the anchor material is forcibly cut.

[0003]

The conventional method for cutting an underground anchor material described above has the following problems. <B> The method of cutting off gas when a worker descends inside a shaft is extremely uneconomical and dangerous, and the anchor material submerged deeper than the groundwater level could not be treated. <B> How to forcibly cut with an auger machine,
This is possible when the anchor material is a steel material, but when the anchor material is elastic like a PC steel wire, the PC steel wire is wound around the auger head and cutting is difficult. There was also a risk that the auger itself would not be able to rotate. <C> Further, in such a case, the anchor material is cut at the mouth side and has no tension. Therefore, when a cutting force is applied, the anchor material moves and the cutting is difficult. In addition, since the auger head may rotate under the anchor material in some cases, there is a problem that the mouth material is cut off and the free anchor material is involved.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional problems, and has been made in consideration of an existing underground where an elastic anchor material can be reliably cut by an economical method. An object of the present invention is to provide a method for cutting an anchor material.

[0005]

In order to achieve the above object, an existing method for cutting an underground anchor material according to the present invention is to rotate and slide a casing pipe having a cutting blade at its tip inside a casing pipe. The auger head is provided at the tip of the auger, and the auger head is provided with an auger device provided with an engagement ring having a plurality of engagement grooves formed on the edge thereof. The auger head penetrates into the ground while removing soil by rotation,
Then, the existing anchor material is engaged with the engagement groove of the engagement ring attached to the auger head, and then the anchor material is cut by the cutting blade at the tip of the casing pipe. Things.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an existing underground anchor material cutting method of the present invention will be described below with reference to the drawings.

[0007]

[Equipment used]

<A> Auger with casing The apparatus used for the cutting method of the present invention is an auger machine with a casing. This device excavates the ground at the tip,
Inside a casing pipe 1 having a cutting blade to be crushed,
The auger 2 is positioned so that it can rotate and slide freely. The casing pipe 1 and the internal auger 2 are structured to rotate in mutually opposite directions.

<B> Auger 2 The auger 2 is provided with a screw for discharging the earth around a central rod, and an auger head 21 is provided at the tip of the auger 2. The auger head 21 is formed with a blade for excavation at the tip, and the engagement ring 3 is integrally attached thereto.

<C> Engagement Ring 3 The engagement ring 3 is a short cylindrical body having an outer diameter substantially equal to the inner diameter of the casing pipe 1, and a plurality of engagement grooves 31 are formed in the edge of the tip. Set up. The engagement groove 31 is formed in a semicircular shape, and has a radius substantially equal to the radius of the anchor member 4 to be cut. The auger 2 rotates independently of the casing pipe 1 by a driving device installed at the upper end and can move up and down. Therefore, the engagement ring 3 attached around the tip of the auger 2 is also independent of the casing pipe 1. To rotate and move up and down.

[0010]

[Method of use] Next, the method of use will be described. <B> Penetration into the ground Although both the tip of the auger head 21 and the tip of the casing pipe 1 are provided with blades, excavation is generally performed with the auger head 21 slightly advanced. Auger head 21
Since a screw 22 is provided at the upper part of the hole, excavation is performed while continuously discharging the soil with the screw 22.

<B> Engagement by the engagement groove 31 (FIG. 3) When the auger head 21 hits the existing anchor material 4 existing in the ground, the auger head 21 precedes the casing pipe 1, so that the auger head 21 The existing anchor material 4 is engaged with the engagement groove 31 of the engagement ring 3 attached to the engagement ring 21. The anchor material 4 is tensed during use, but after use, the mouth is cut off to release the tension. For this reason, conventionally, there has been a problem that the auger head 21 is rotated and wound under the anchor member 4 as described above. However, when the device of the present invention is used, the engagement ring 3 is located around the auger head 21, and when the engagement ring 3 rotates, the anchor material 4 is engaged with the engagement groove 31.
To be pressed down from above.

<C> Cutting (FIG. 4) Even if the anchor material 4 has elasticity, it is impossible to move the auger head 21 under the anchor material 4 by suppressing the anchor material 4 from above. Engagement ring 3
When the anchor member 4 is pressed by the, the rotation of the auger 2 is stopped. Then, while rotating the casing pipe 1, the casing pipe 1 is advanced into the ground, and the anchor material 4 is rotated by the cutting blade at the tip of the casing pipe 1.
Disconnect. As described above, the anchor material 4 is cut at the mouth side and generally moves and is difficult to cut because no tension is applied. However, in the method of the present invention, the casing pipe is formed by the engagement ring 3. Since it is fixed so that it does not move laterally at the position of the tip of the casing pipe 1, it can be easily cut by the tip of the casing pipe 1.

[0013]

As described above, the existing method of cutting the underground anchor material 4 according to the present invention is described above. Therefore, the auger head 21 of the conventional screw rotates under the anchor material 4 and as a result, the mouth side is lowered. Anchor material 4 in free state
Can be prevented from being involved. As a result, the existing anchor member 4 buried underground can be reliably cut at a required position. Therefore, even in a site where the existing anchor material 4 is buried, it is possible to construct a ridge and a cast-in-place pile.

[Brief description of the drawings]

FIG. 1 is an illustration of an apparatus used in the method of the present invention.

FIG. 2 is an explanatory view of an auger head of an apparatus used in the method of the present invention.

FIG. 3 is an explanatory diagram of a cutting state.

FIG. 4 is an explanatory diagram of a cutting state.

FIG. 5 is an explanatory view of a use state of an anchor

Claims (1)

(57) [Claims] An auger head is provided at the tip of an auger rotatably and slidably inside a casing pipe having a cutting blade at a tip thereof. Using an auger device equipped with an engagement ring with a recessed groove, the auger head enters the ground while rotating the auger to remove the soil, and then the existing auger is inserted into the engagement groove of the engagement ring attached to the auger head. An existing underground anchor material is cut by engaging the anchor material of the present invention and then cutting the anchor material by the cutting blade at the tip of the casing pipe.