JPH04302693A - Excavating engineering method - Google Patents

Abstract

PURPOSE:To provide a excavating engineering method with simple processes and high economy. CONSTITUTION:There are provided a cylindrical pipe 7 provided on the side with a strainer 8, an excavating tool inserted slidably in the pipe 7 and having on the tip bits 5A, 5B capable of expanding the diameter larger then the outer diameter of the pipe 7 and an excavating equipment consisting of a diameter expanding section 9 and diameter contracting section 10 for regulating the movement of the excavating tool in the direction of tip of the pipe 7. The bits 5A, 5B are projected from the pipe 7 and expand the diameter for excavation, while the pipe 7 is inserted into the ground. After the excavation, the bits 5A, 5B are contracted in the diameter, only excavating tool is drawn out of the pipe 7 and the outer wall of the excavated hole is made of the pipe 7 left in the excavated hole as it is. Further, a filler is forced into the excavated hole to leach from the strainer 8 into the foundation around the excavated hole.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is an excavation method in which the ground is excavated using an excavation tool, and the periphery of the resulting hole is reinforced with a pipe to prevent the collapse of the hole wall. , and a highly economical excavation method.

0002

2. Description of the Related Art Conventionally, the following methods are known as methods for drilling holes in the ground, etc. The process will be explained with reference to FIGS. 12 and 13.

In FIG. 12, 16 is an earth auger whose blade is made of a cemented carbide tip or the like, and 19 is a casing tube. The earth auger 16 is slidably inserted into the casing tube 19, and excavation is carried out by pressing the earth auger 16 in the direction of arrow P in the figure, pressing the head 17 of the earth auger 16 onto the ground 11, and digging. This is done by rotating the auger 16 in the Q direction in the figure. On the other hand, the casing tube 19 is moved up and down along the wall of the borehole 12 formed by the earth auger 16, and is inserted into the borehole 12 while scraping off the earth and sand remaining on the borehole wall. Further, the earth and sand generated by excavation is discharged upward by the auger screw 18.

FIG. 13 shows the situation at the end of excavation in the conventional excavation method. After the earth auger 16 and the casing tube 19 are pulled up from the excavated hole 12, the pipe 7 forming the outer wall of the excavated hole 12 is inserted into the excavated hole 12. Here, the inner diameter of the excavated hole 12 must be sufficiently larger than the outer diameter of the pipe 7 so that the pipe 7 can be inserted therein.

[0005]

However, in the conventional excavation method described above, the casing tube 19 and the pipe 7 had to be used together. In addition, drilling hole 12
In order to make the inner diameter of the pipe 7 sufficiently larger than the outer diameter of the pipe 7, there was a problem in that excessive excavation had to be performed. Furthermore, since the gap is large, in order to increase the stability of the pipe 7 inside the excavation hole 12, work such as filling the gap between the excavation hole 12 and the pipe with concrete or the like is performed as necessary after inserting the pipe 7. Something happened. All of these problems not only reduce work efficiency but also cause problems in terms of saving materials. Furthermore, the conventional method described above has a problem in that it is difficult to create the excavation hole 12 in the soft ground 11 because it does not have a means for directly stabilizing the ground 11.

[0006]

[Means for Solving the Problems] The present invention provides an excavation method in which excavation is performed using an excavation tool, and the periphery of the excavation hole formed by the excavation is reinforced with a pipe for preventing collapse of the hole wall.

[0007] A cylindrical pipe, a strainer formed in a part of the pipe and having a flow path that penetrates the wall surface of the pipe, and a strainer that is inserted into the pipe and whose tip can be expanded to a diameter larger than the outer diameter of the pipe. and a regulating member that regulates movement of the excavating tool toward the tip of the pipe,

[0008] Excavation is performed with the bit protruding from the tip of the pipe and with its diameter expanded, and the pipe is inserted into the ground. After the excavation is completed, the bit is reduced in diameter and only the excavation tool is This is an excavation method in which the filler is pulled up from an excavation hole, and then a filler is pressurized into the excavation hole, and the filler is leached into the ground around the excavation hole from the flow path.

[0009]

[Operation] In the present invention, the inner diameter of the borehole formed by excavation is greater than or equal to the outer diameter of the pipe inserted into the borehole, and the difference between the inner diameter and the outer diameter is extremely small. In this case, the pipe inserted into the borehole can be directly used as the outer wall of the borehole. Therefore, the excavation process is simplified and the materials required for excavation are saved.

Furthermore, the ground around the pipe can be strengthened by the action of the filler leached into the ground from the flow path. Therefore, stable drilling holes can always be created in any ground.

[0011]

Embodiments Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

Examples of excavation tools used in the present invention are shown in FIGS.
Shown in Figure 3. This excavation tool has two points symmetrical about the center of the device 2 on the bottom surface of the device 2, which receives the impact force of a hammer (not shown) and the rotational force of the hammer cylinder 1, which is driven by compressed air. Forming shaft holes 2A and 2B,
The bit shafts 3A, 3B are fitted into the respective shaft holes 2A, 2B so as to be rotatable around the shaft and not come off. Bits 5A and 5B each having a substantially semicircular shape and having a large number of tips 4 implanted in their tip surfaces are provided with their straight end surfaces 6A and 6B facing each other, and the positions of the bit shafts 3A and 3B are adjusted according to the device. 2 rotates in a predetermined direction, bits 5A and 5B
protrude from the outer peripheral surface of the device 2 by a predetermined amount of excavation, and at that time, the straight end surfaces 6 of both bits
A and 6B are offset from the center of the device 2 so that they abut each other.

The excavation tool is slidably inserted into a pipe 7 having approximately the same diameter as the cutting tool, and a part of the pipe 7 is provided with a flow path penetrating the wall surface of the pipe 7, if necessary. A strainer 8 with 8A is provided. This strainer 8 is for allowing liquid to seep from the wall surface of the pipe 7 into the ground 11 around the excavation hole 12, and the shape of the flow path 8A can be arbitrarily selected according to the geology of the ground 11 where excavation is to be performed. Configurable.

Examples of the shape of the flow path 8A are shown in FIGS. 4 and 5. FIG. 4 shows an example in which a slit-like elongated hole is provided along the axial direction of the pipe 7, and FIG. 5 shows an example in which a round hole is provided. Furthermore, a diameter-reducing tube 10 that fits in the diameter-enlarged portion 9 formed on the outer peripheral surface of the device 2 is integrally fixed to the inner periphery of the tip of the pipe 7 by a method such as welding.

Next, the excavation method according to the present invention using the above-mentioned excavation tool will be explained.

FIG. 6 shows the excavation situation in the above example. In this case, bits 5A and 5B are pipe 7
When the device 2 is protruded from the tip and rotated in a predetermined direction (arrow X in FIG. 3) by the hammer cylinder 1, the bit 5
A and 5B rotate around the bit shafts 3A and 3B due to excavation resistance from the state shown in FIG. 2, and as a result, the state shown in FIG.
As shown in FIG.
One end protrudes from the outer peripheral surface of the device 2 by a predetermined amount, and a portion of the straight end surfaces 6A, 6B abuts each other,
The rotation of bits 5A and 5B stops. When the rotational force of the device 2 and the impact force of the hammer are applied to the bits 5A and 5B in this state, the bits 5A and 5B move up and down, causing local crushing and shear failure of the ground 11 by the chips 4, and excavation is carried out. be exposed.

On the other hand, due to the contact between the enlarged diameter part 9 and the reduced diameter pipe 10 due to the vertical movement, the impact force of the hammer is transmitted to the pipe 7 simultaneously with excavation, and the impact force and the weight of the pipe 7 cause the pipe 7 to The tip digs into the ground 11. Here, since the reduced diameter pipe 10 is located below the enlarged diameter part 9, the impact force is transmitted only in the direction of pushing the pipe 7 into the ground 11, and as a result, water etc. seeping from the wall of the excavation hole 12 Collapse of the pore walls is effectively prevented.

In addition, the compressed air discharged when the hammer piston (not shown) falls inside the hammer cylinder 1 is used to remove the earth and sand generated as a result of excavation through the air holes 13A and 13B provided at the bottom of the device 2. By being blown out, it is separated from the tip of the excavation tool, and then moves into the pipe 7 via the discharge groove 14 provided in the device 2, and is discharged further upward from there.

FIG. 7 shows the situation at the end of excavation in the above example. In this case, by rotating the hammer cylinder 1 in the opposite direction to the predetermined direction and returning the bits 5A, 5B to the positions shown in FIG. By pulling upward, only the excavation tool can be pulled upward from the excavation hole 12, as shown in FIG. As a result, drilling hole 12
Inside, only the pipe 7 and the reduced diameter tube 10 remain, as shown in FIG.

Furthermore, in the present invention, a filler 2 such as water glass or bentonite is directed from the flow path 8A to the ground 11.
0, and the filler 20 is leached and diffused into the ground 11 around the excavation hole 12 as shown in FIG.
The ground 11 in that part can be strengthened, and the pipe 7 and the ground 11 can be integrated. On the other hand, since the outer diameter of the bits 5A and 5B when expanded and the outer diameter of the pipe 7 are approximately the same, the drilled hole 1 formed by drilling
The gap α between the inner diameter of the pipe 7 inserted into the borehole 12 and the outer diameter of the pipe 7 inserted into the borehole 12 is extremely small. Can be used directly as an exterior wall. Therefore, in combination with the reinforcement of the ground 11 due to the leaching of the filler 20 from the channel 8A, it is possible to always create a stable excavation hole 12 even in the soft ground 11.

Furthermore, if a reinforcing member such as a reinforcing cage or a steel frame is inserted into the pipe 7 and then filled with concrete, the concrete seeped into the ground 11 from the channel 8A and the excavated hole 1 are removed.
Since the concrete in 2 solidifies together through the flow path 8A, a very stable foundation pile is obtained.

[0022] Here, the number of divided bits that can be expanded in diameter is 3.
In addition, as shown in FIG. 11, if necessary, a down-the-hole bit 15 may be installed at the tip of the hammer cylinder 1 instead of the expandable bits 5A and 5B as in the above example. It is also possible to attach a conventional drilling tool to perform drilling. Furthermore, if the pipe 7 is made splittable into a plurality of parts along its axial direction, it is also possible to split the pipe 7 within the excavation hole 12 and pull it up from the excavation hole 12 as necessary.

[0023]

[Effects of the Invention] As explained above, in the present invention,
Since the inner diameter of the borehole formed by excavation is greater than or equal to the outer diameter of the pipe inserted into the borehole, and the difference between the inner diameter and the outer diameter is extremely small, the pipe is directly used as the outer wall of the borehole. We were able to. This not only simplified the excavation process but also saved the materials needed for excavation. Furthermore, the ground around the pipe could be strengthened by the action of the filler that oozed into the ground from the channel provided in the strainer. As a result, it has become possible to create stable drilling holes at all times in any ground.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an excavation tool used in a first embodiment of the present invention.

FIG. 2 is a plan view showing a state in which the diameter of the bit is reduced in the excavation tool used in the first embodiment of the present invention.

FIG. 3 is a plan view showing a state in which the diameter of the bit is expanded in the excavation tool used in the first embodiment of the present invention.

FIG. 4 is a diagram showing an example of the shape of a flow path in the present invention.

FIG. 5 is a diagram showing an example of the shape of a flow path in the present invention.

FIG. 6 is a side sectional view showing the state of excavation work in the first embodiment of the present invention.

FIG. 7 is a side sectional view showing the situation at the end of excavation in the first embodiment of the present invention.

FIG. 8 is a side sectional view showing the situation of the excavation tool lifting operation in the first embodiment of the present invention.

FIG. 9 is a side cross-sectional view showing the situation before the filler is press-fitted in the first embodiment of the present invention.

FIG. 10 is a side sectional view showing the situation after the filler is press-fitted in the first embodiment of the present invention.

FIG. 11 is a side sectional view showing the state of excavation work in a second embodiment of the present invention.

FIG. 12 is a side sectional view showing the state of excavation work in a conventional excavation method.

FIG. 13 is a side sectional view showing the situation at the end of excavation in a conventional excavation method.

[Explanation of symbols]

1 Hammer cylinder 2 Devices 2A, 2B Shaft holes 3A, 3B Bit shaft 4 Tips 5A, 5B Bits 6A, 6B Straight end surface 7 Pipe 8 Strainer 8A Flow path 9 Expanded diameter section 10 Reduced diameter pipe 11 Ground 12 Drilled hole 13A, 13B Air hole 14 Discharge groove 15 Down-the-hole bit 16 Earth auger 17 Head 18 Auger screw 19 Casing tube 20 Filler α Gap between the inner diameter of the drilled hole and the outer diameter of the pipe inserted into the drilled hole

Claims (2)

[Claims] Claim 1: An excavation method in which excavation is carried out using an excavation tool, and the circumference of the excavated hole formed by the excavation is reinforced with a pipe to prevent collapse of the hole wall. a strainer having a flow path formed therein and penetrating the wall surface of the pipe; and a strainer inserted into the pipe;
The excavation equipment includes an excavation tool equipped with a bit that can be expanded to a diameter larger than the outer diameter of the pipe at its tip, and a regulating member that restricts movement of the excavation tool toward the distal end of the pipe. Excavation is performed with the pipe protruding from the tip and expanded in diameter, and the pipe is inserted into the ground. After the excavation is completed, the diameter of the bit is reduced and only the excavation tool is pulled up from the excavation hole. An excavation method characterized in that a filler is press-fitted into an excavation hole, and the filler is leached into the ground from the flow path. 2. The excavation method according to claim 1, wherein the excavated hole is filled with concrete after the filler is press-fitted.