JPH06240974A - Ground excavation method and ground excavator - Google Patents

Abstract

PURPOSE:To excavate an accurate hole in an efficient manner by boring a pilot hole in the ground with each space at both sides, and inserting a tension rod of a traction excavator into this hole, while discharging digged earth from the pilot hole. CONSTITUTION:A pilot hole 2 is bored (A) in an existing space from the ground by a boring machine 21. Next, a tension rod 4 is inserted into this pilot hole 2, and an excavator 1 equipped with a revolving bit in the front is connected to this rod 4 and digging B takes place as pulling this rod 4. At this time, digged earth and sand produced are discharged out of the pilot hole. In succession, pressure is added to a digging part and the digging continues as preventing any looseness of the ground, while the circumference of a boring hole is lined (C) by a segment 51. With this constitution, such a hole as being excellent in working accuracy can be digged in an efficient manner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ground excavation.

[0002]

2. Description of the Related Art Conventionally, in various construction works in an urban area, it is difficult to underpin the existing structure, or to excavate from the ground or construct a structure such as a pile due to the use condition of the existing space. There are many cases. What is common to such construction is that subsidence of the surrounding ground is not allowed, very high construction accuracy is required, and
The construction space is extremely limited. In the conventional ground excavator, the machine is downsized so that it can fit in a limited construction space, the ground is excavated from the ground surface, the excavation hole is formed, and structures such as piles are created. Most common are deep foundation piles and reverse pile construction methods, but with these methods,
In addition to the fact that it is indispensable to use the ground improvement work (injection, etc.) to prevent the loosening of the ground, it also makes it difficult to use the existing facilities because the occupied space on the ground is long. is there.

[0003]

However, the conventional method has the following problems. <a> In the conventional ground excavator, loosening of the excavated ground occurred, and auxiliary work such as ground improvement was essential. <B> A long-term occupied space was required as a construction space. <C> The work time was fixed, and the work was divided (1 to 2 hours), resulting in poor work efficiency.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a ground excavation method and a ground excavator capable of accurate excavation.

[0005]

According to the present invention, in a ground excavation method for excavating a ground having a space on both sides, a pilot hole having a cross-sectional area smaller than that of the drill hole is formed at a position where the drill hole is formed in the ground. Form, insert a rod into the pilot hole, place an excavator on one side of the ground, fix it to the rod, apply tension to the rod from the other side of the ground, and use the tension The excavator is pressed against the ground to excavate the ground, and the excavated soil is expelled through the pilot hole, or the soil is excavated into the pilot hole formed in the ground having a space on both sides. In a ground excavator for forming an excavation hole in the ground by utilizing the tension of the rod, a rod fixing part that fixes one end of the rod, a rotatable excavation blade having an excavation bit on the ground side, and the excavation Drive to rotate the wings With the door to rotate the 該掘 Kezutsubasa, in ground excavation machine, characterized in that drilling 該地 board along the pilot hole.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. <A> Outline of excavation construction method When there is an existing space 3 in the ground and the excavation hole 5 is formed between the existing space 3 and the surface of the ground, first, a pilot hole having a small diameter is formed in the ground where the excavation hole 5 is to be formed. Form 2. The tension rod 4 is inserted into the pilot hole 2, the excavator 1 in the existing space is attached to the tension rod 4, and the excavator 1 is pulled up. The excavator 1 rises while excavating the ground along the pilot hole 2 to form an excavation hole 5. At that time, the excavated earth and sand is discharged to the ground through the pilot hole 2. The drill hole 5 has a segment 51 on the periphery thereof.
It is formed while being reinforced with.

<B> Excavator 1 A rotatable excavation blade 11 is attached to the front of the excavator 1.
The drill bit 12 is formed on the front surface of the drill blade 11,
The ground is excavated by rotating. In order to attach the tension rod 4 to the excavator 1, an opening is provided in the center of the excavation blade 11 so that the tension rod 4 can pass through, and the tension rod 4 is fixed to the rod fixing portion 18.
In order to take in the excavated sediment and remove it through the pilot hole 2, the excavator 1 is provided with a sediment intake port 13,
Through this, excavated earth and sand is pushed out from the pilot hole 2. . The excavation blade 11 is rotated by a rotary motor 16 installed inside the excavator 1. In order to stir the earth and sand, the earth and sand kneading blade 14 is installed in the excavator 1. The rear part of the excavator 1 has a tail 17, and the segment 51 can be attached to the excavated wall surface.

<C> Excavation procedure If there is an existing space 3 such as an underpass, an excavation procedure for constructing a drill hole between this space and the ground will be described. The pilot hole 2 is formed in advance at the position where the excavation hole 5 is formed. The pilot hole 2 is formed by a boring machine 21 in a usual manner so as to have a small diameter. The tension rod 4 is passed through the pilot hole 2. The excavator 1 is arranged in the existing space 3, and the tension rod 4 is attached to the rod fixing portion 17 of the excavator 1. Tension rod 4 above the ground
Can be pulled up with a jack. When the tension rod 4 is pulled, the excavator 1 is lifted and pressed against the ground. The excavation blade 11 of the excavator 1 is rotated to form the excavation hole 5 in the ground by the excavation bit 12. The excavated earth and sand enters the earth retaining chamber 15 at the back of the excavation blade from the earth and sand intake port 13 and is agitated by the earth and sand mixing blade 14. After that, by the reaction of the thrust applied to the excavator 1, it is squeezed forward in the excavation direction, and the earth and sand is discharged to the earth and sand pit 7. Since the excavated part is always under pressure, the ground will not loosen. The excavated earth and sand are pushed up by the rise of the excavator 1. At this time, if the excavated soil is hard and difficult to discharge, muddy water, clay, water or the like is added to the soil retaining chamber 15 to form a slurry, which enables continuous soil removal. Furthermore, the effect of stabilizing the face of the natural excavation can be expected. Along with the progress of excavation, earth retaining materials such as the segment 51 are assembled from the tail 17 of the excavator 1. Further, since the pilot hole 2 is provided in advance, the excavation hole is accurately formed without bending.

[0009]

According to the present invention, the following special effects can be obtained. <B> Since the pilot hole is formed in advance, the drilling hole construction accuracy is improved. <B> Because the excavated part is always under pressure,
Looseness of the ground can be controlled very little. <C> By separating the processes of excavation, sediment removal, and soil retaining (segment) assembly, the work space is prevented from becoming complicated as in the conventional shield construction method.
The safety can be improved. <D> Since the carried-out sediment is carried out by utilizing the reaction of thrust, the excavated sediment can be effectively used as general sediment without weakening the sediment more than necessary and without adding water.

[Brief description of drawings]

[Fig. 1] Construction drawing of excavation hole

[Fig. 2] Structural diagram of the excavator

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoji Yokoyama 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation

Claims (2)

[Claims] 1. A ground excavation method for excavating a ground having a space on both sides, wherein a pilot hole having a cross-sectional area smaller than that of the drill hole is formed at a position where the drill hole is formed in the ground, and a rod is provided in the pilot hole. Insert, place the excavator on one side of the ground, fix it to the rod, apply tension to the rod from the other side of the ground, press the excavator against the ground using the tension, A method of excavating the ground, characterized by excavating the ground and removing the excavated soil through pilot holes. 2. A ground excavator for forming an excavation hole in the ground by utilizing the tension of a rod inserted in a pilot hole formed in the ground having a space on both sides. A rod for fixing one end of the rod. A fixed part, a rotatable excavation blade having an excavation bit on the ground side, and a drive source for rotating the excavation blade, and rotating the excavation blade to excavate the soil along the pilot hole A ground excavator.