JP2005083007A - Method for laying square pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for laying a square pipe capable of smoothly driving a buried pipe into a bedrock even if a sectional shape of the buried pipe to be buried in the ground is formed in the shape of a square. <P>SOLUTION: When the square pipe 1 is driving into the bedrock 50, a guide edge 2 is mounted to the front end section of the square pipe 1, jet nozzles 18b of a water jet injection device 18 are mounted to four corners of the guide edge 2 to excavate the bedrock 50 in the front of the square pipe 1 by an auger bit 12b and, at the same time, four corners of the inside of the square pipe 1 are also simultaneously excavated while injecting jet water from the jet nozzles 18b to the inside of the bedrock 50 so that the square pipe 1 can be inserted into the bedrock 50. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention, for example, has a square cross-sectional shape such as a square steel pipe used to construct an arch-shaped underground structure such as a preceding support that is installed prior to tunnel excavation. It relates to a method of burying pipes in natural ground.

In general, in excavation and support when the tunnel wellhead and soil covering are thin, it is necessary to form a flat arch on the ground, so a large number of cylinders are formed along the arch in the axial direction of the tunnel. There is a method of reinforcing the above natural ground by propelling and burying them adjacent to each other. Specifically, as shown in FIG. 3 (a), a large number of steel pipes 21 with joints extending in the axial direction of the tunnel are adjacent to each other in the natural ground 50 as an arch part along the arch part. There has been proposed a method of constructing a tunnel by excavating the inside of the preceding support work 20 after it has been propelled and buried and used as the preceding support work 20. Specifically, as shown in FIG. 3B, the steel pipe 21 with a joint has a trapezoidal steel main body 21m and a steel pipe with a joint adjacent to the upper end and lower end of both side surfaces of the main body 21m. 21a and 21b and joints 21c and 21d, respectively, which protrude to the upper end and lower end of the side surface of the main body 21m, and a joint 21p to be engaged with the joints 21a to 21d. There are two types of steel pipes 21B with a second joint provided with 21s, and the second joint-attached steel pipe 21B adjacent to the first steel pipe with a joint 21A is included in the joints 21a and 21b of the first steel pipe with a joint 21A. The joints 21p and 21q are fitted to each other.
As a method for propelling the steel pipe with joint 21A, for example, as shown in FIG. 3C, PC stranded wires 22 and 22 connected to a traction device (not shown) are attached to the front surface of the steel pipe with joint 21A. The joints 21p and 21q are fitted to 21a and 21b, respectively, and the jointed steel pipe 21A is connected to the jointed steel pipe 21B and the jointed steel pipe 21A is pulled. At this time, the auger drilling device 23 is set in the steel pipe 21A with the joint, and the steel pipe 21A with the joint is propelled while excavating a natural ground in front of the steel pipe 21A with the joint. After embedding the steel pipe with joint 21A, the auger hole drilling device 23 is pulled out, and concrete is filled into the steel pipe with joint 21A to construct the preceding support structure 20 (see, for example, Non-Patent Document 1).

When embedding a cylinder as described above, in general, an auger type drilling hole in which the auger screw is rotated in the buried pipe to excavate and remove the sand and press the buried pipe from behind to bury it. A propulsion device is used. FIGS. 4A to 4C are diagrams showing the configuration of a conventional auger type drilling propulsion machine 30, which is provided inside the buried pipe 31 and the buried pipe 31. A pressing device (hydraulic cylinder) for the buried pipe 31 movably installed along a casing 32, an auger screw 33 pierced in the casing 32 so as to freely advance and retract, and a guide rail 34 laid in the shaft 51. 35) and a drive unit 36 that also serves as a propulsion device for the auger screw 33, and the buried pipe 31 is propelled while excavating the natural ground 50 with the auger screw 33. Then, when the buried pipe 31 and the auger screw 33 having a predetermined length reach a predetermined depth, the operation of adding the buried pipe 31 and the auger screw 33 and advancing excavation is repeated, and the buried pipe 31 is moved in the propulsion direction. It is buried in the natural ground 50 while being connected. In this auger type drilling propulsion machine 30, a leading conduit 37 is provided at the tip of the buried pipe 31, and the earth and sand excavated by the excavating blade 33k of the auger screw 33 are smoothly guided into the casing 32 ( For example, see Patent Document 1).
JR East Japan Brochure; “Rinkai Fukutoshin Line and other new construction” Japanese Patent Laid-Open No. 55-122996 (pages 2, 3 and 1 to 4)

  However, the conventional auger type drilling machine 30 has no problem when the buried pipe 31 is a cylindrical tube, but the section of the buried pipe has a square shape like the steel pipe 21 with a joint. In the case of this tube, the corner of the square tube could not be excavated. That is, since the auger screw 33 and its excavating blade 33k are configured to excavate the natural ground 50 while rotating, the earth and sand at the corner of the square tube outside the rotational range of the excavating blade 33k can be sufficiently removed. Since it cannot be excavated and discharged, it is difficult to smoothly promote a square tube such as the steel pipe 21 with a joint.

  The present invention has been made in view of the conventional problems, and even when the cross-sectional shape of the buried pipe buried in the ground is a square shape, the corner capable of smoothly propelling the buried pipe into the ground. An object is to provide a method for burying a mold tube.

  According to the first aspect of the present invention, a cylindrical inner tube is installed in a square tube, and an auger drilling device having a drilling blade attached to the tip of a rotating screw is inserted into the inner tube. A method of embedding a square tube in which the square tube, the inner tube, and the auger drilling device are simultaneously promoted while excavating a natural ground using the auger drilling device, and the square tube is embedded in the natural ground. A cylindrical guide blade along the outer periphery of the rectangular tube is attached to the distal end portion of the rectangular tube, and the distal side corner of the gap provided between the rectangular tube and the inner tube The jet water injection nozzle is installed in the section, and the ground water is excavated while jet water from the jet water injection nozzle is sprayed into the natural ground from the inside of the opening of the guide blade. It is a feature.

According to a second aspect of the present invention, in the method for embedding the square tube according to the first aspect, the rear end portion of the guide blade of the inner tube is provided with a contact member that contacts the guide blade. The inner tube and the square tube are integrally propelled, and the jet water injection nozzle is fixed to the inner peripheral side of the guide blade.
According to a third aspect of the present invention, there is provided the square tube embedding method according to the first aspect, wherein the guide blade is attached to a distal end side of the inner tube, and a rear end portion of the guide blade of the square tube. Further, an abutting member that abuts on the guide blade is provided so that the inner tube and the square tube are integrally propelled.

  According to the present invention, when a square tube is embedded in a natural mountain while excavating the natural mountain using an auger drilling device, a cylindrical shape along the outer periphery of the rectangular tube is provided at the tip of the rectangular tube. And installing a jet water injection nozzle at the corner on the tip side of the gap provided between the square tube and the inner tube, the jet water from the jet water injection nozzle, The ground is excavated from the inside of the opening of the guide blade into the ground, and the square pipe is inserted into the ground, so that the four corners inside the square pipe are effectively removed. It can be excavated, and the square tube can be smoothly pushed into the ground.

Hereinafter, the best mode of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing a schematic configuration of an auger type drilling propulsion machine according to the best mode. In each figure, 1 is a square tube having a rectangular cross-sectional shape embedded in a natural ground 50, A propulsion pipe 11 having the same outer shape as the square pipe 1 and having a cylindrical hollow portion, and a drilling blade (hereinafter referred to as an auger bit) 12b installed at the tip of a rotating screw 12a installed in the propulsion pipe 11 An auger type equipped with an auger drilling device 12 to which an auger is attached, and a propulsion device 13 and a guide cell 14 installed in a shaft 51 for propelling the auger drilling device 12 and the propulsion pipe 11 simultaneously. Drilling propulsion machine.
The propulsion tube 11 and the rear end side of the auger hole drilling device 12 are both fixed to a propulsion member mounting portion 15 provided at the tip of the propulsion device 13 and are propelled integrally by the propulsion device 13. The Reference numeral 16 denotes a hydraulic jack for propelling the rear end portion of the propulsion pipe 11 to assist the propulsion of the propulsion pipe 11.
In this example, the right angle triangular guide blade 2 whose cross-sectional shape becomes narrower in the traveling direction of the square tube 1 is attached to the distal end side of the square tube 1 disposed on the outer peripheral side of the propulsion tube 11; An abutting member 17 that abuts the back side of the guide blade 2 is attached to the rear end of the guide blade 2 on the front end side of the propulsion tube 11, and the propulsion device 13 and the auger milling are performed by the propulsion device 13. The hole device 12 and the square tube 1 are simultaneously pushed into the natural ground 50.
Reference numeral 18 denotes a water jet injection device provided with jet nozzles 18b attached to four corners of the guide blade 2 and connected to a high pressure water supply device (not shown) via a high pressure hose 18a, and 19 denotes an inner wall of the propulsion pipe 11. And muddy water discharging means for discharging muddy water including the discharged soil sent through the gap between the blades of the screw 12a and the outside.
Since there is a space between the inner wall of the rectangular tube 1 and the outer wall of the propulsion tube 11, the high-pressure hose 18a of the water jet spray device 18 can be accommodated in the space.

Next, a method for propelling the square tube 1 into the natural ground 50 using the auger type drilling propulsion machine 10 will be described.
First, the square tube 1 is mounted on the guide cell 14, and then the propelling tube 11 is fixed to the propelling member mounting portion 15 and the auger drilling device 12 is rotatably fixed to the propelling member mounting portion 15. The propulsion device 13 is driven to advance the propulsion tube 11 and the auger drilling device 12 and insert them into the square tube 1. When the propulsion tube 11 and the auger hole drilling device 12 are further advanced, the abutting member 17 of the propulsion tube 11 abuts on the back surface of the guide blade 2 attached to the distal end portion of the square tube 1 and the square shape. Since the pipe 1 is pushed forward, the propulsion pipe 11, the auger drilling device 12 and the square pipe 1 are simultaneously propelled into the natural ground 50.
At this time, as shown in FIGS. 2 (a) and 2 (b), a natural ground 50 on the front surface of the square tube 1 is inserted by an auger bit 12b provided on the distal end side of the auger drilling device 12. While excavating, high pressure jet water is jetted into the natural ground 50 from the jet nozzle 18b of the water jet sprayer 18 attached to the four corners of the guide blade 2, and the outer periphery of the auger bit 12b and the corner A natural ground 50 between four corners on the inner peripheral side of the mold tube 1 (hereinafter referred to as four corners inside the square tube 1) is excavated. Thereby, since the natural ground 50 at the four corners inside the square pipe 1 that could not be excavated by the auger bit 12b can be excavated simultaneously, the square pipe 1 can be smoothly pushed into the natural ground 50.
Further, since the jet water from the jet nozzle 18b is concentrated and ejected in a narrow area between the guide blade 2 and the outer peripheral portion of the auger bit 12b, the natural ground 50 can be excavated efficiently, and surplus excavation is performed. It is difficult to form a void due to the water, and the water of the jet water does not diffuse, so the weakening of the ground can be prevented.
The muddy water including the soil excavated from the natural ground 50 is sent to the muddy water discharging means 19 through the gap between the inner wall of the propulsion pipe 11 and the blade portion of the screw 12a and discharged to the outside.
Further, when the square tube 1, the propulsion tube 11, and the auger drilling device 12 having a predetermined length reach a predetermined depth, the square tube 1, the propulsion tube 11, and the auger drilling device 12 are installed as in the conventional case. Continue the excavation again.

Thus, in this best mode, when the square tube 1 is propelled into the natural ground 50, the guide blade 2 is attached to the tip of the square tube 1, and further, at the four corners of the guide blade 2. The jet nozzle 18b of the water jet spraying device 18 is attached, and the ground 50 in front of the square tube 1 to be inserted is excavated by the auger bit 12b, and the jet water from the jet nozzle 18b is discharged into the ground 50. The square tube 1 is inserted into the natural ground 50 while simultaneously excavating the four corners inside the square tube 1 so that the inside of the square tube 1 that cannot be excavated only by the auger bit 12b is used. Therefore, the square pipe 1 can be smoothly pushed into the natural ground 50.
Moreover, since the jet water from the jet nozzle 18b is concentrated and ejected in the narrow area | region between the said guide blade 2 and the outer peripheral part of the auger bit 12b, a natural ground can be excavated efficiently.

In the best mode, the outer shape of the propulsion tube 11 is the same as that of the square tube 1, but it may be cylindrical. At this time, in order to reliably propel the square tube 1, the contact area between the contact member 17 and the guide blade 2 can be increased by making the outer shape of the contact member 17 the same as that of the square tube 1. desirable. In addition, while changing the position of the contact member 17, you may make it attach separately to the square tube 1 the member in which the back side contact | abuts the front surface of the said contact member 17. FIG.
Further, the jet nozzle 18b is not necessarily attached to the guide blade 2, and the jet port of the jet nozzle 18b only needs to be located inside the guide blade 2, so that, for example, the inner wall of the rectangular tube 1 and the propulsion are propelled. A holding member may be provided between the outer wall of the tube 11 and the jet nozzle 18b may be attached to the holding member.
Alternatively, the guide blade 2 is attached to the front end side of the propulsion tube 11, and a contact member that contacts the guide blade 2 is provided behind the guide blade 2 at the front end portion of the square tube 1, The propulsion tube 11 and the square tube 1 may be integrally propelled. In this case as well, the jet nozzle 18b may be attached to the inside of the opening of the guide blade 2.

  As described above, according to the present invention, the square pipe can be propelled while effectively excavating the four corners inside the square pipe. A square pipe having a cross-sectional shape such as a square steel pipe used for constructing an underground structure can be easily embedded in a natural ground.

It is a top view which shows schematic structure of the auger type drilling propulsion machine which concerns on the best form of this invention. It is a figure which shows the principal part of an auger type drilling propulsion machine. It is a figure which shows the construction method of the advance support work using the conventional square tube. It is a figure which shows the structure of the conventional auger type drilling machine.

Explanation of symbols

1 square tube, 2 guide blades, 10 auger type drilling propulsion machine, 11 propulsion tube,
12 auger drilling device, 12a screw, 12b auger bit,
13 propulsion device, 14 guide cell, 15 propulsion member mounting portion, 16 hydraulic jack,
17 abutting member, 18 water jet spraying device, 18a high pressure hose,
18b Jet nozzle, 19 Mud discharge means, 50 ground.

Claims (3)

  A cylindrical inner tube is installed in the square tube, and an auger drilling device with a drilling blade attached to the tip of the rotating screw is inserted into the inner tube, and a natural ground is excavated using this auger drilling device. The square tube, the inner tube, and the auger drilling device are simultaneously driven to embed the square tube in a natural ground, and is embedded in the tip of the square tube. A cylindrical guide blade is attached along the outer periphery of the square tube, and a jet water spray nozzle is installed at the tip side corner of the gap provided between the square tube and the inner tube, A method of embedding a square tube, wherein the ground is excavated while jet water from a jet water spray nozzle is jetted from the inside of the opening of the guide blade into the ground.   A contact member that contacts the guide blade is provided at a rear end portion of the guide blade of the inner tube, and the inner tube and the square tube are integrally driven, and the jet water spray nozzle is moved to the guide blade. The square tube embedding method according to claim 1, wherein the method is fixed to the inner peripheral side of the rectangular tube. The guide blade is attached to the distal end side of the inner tube, and a contact member that contacts the guide blade is provided at the rear end portion of the guide blade of the square tube so that the inner tube and the square tube are integrated. The method for embedding a square tube according to claim 1, wherein the square tube is embedded.

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