JPH07111056B2 - Steel pipe digging method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method of constructing a casing pipe in a geological formation during civil engineering work, particularly when a mud layer or a sludge layer is formed between a topsoil and a support layer (rock mass). It is a thing.

[0002]

2. Description of the Related Art Applicants have proposed, as steel pipe erection equipment, Japanese Examined Patent Publication No. 58-45529 (Registration No. 1214277) and Japanese Examined Patent Publication No. 59.
No. 649 (Registration No. 1223623) is provided, but the method of Japanese Patent Publication No. Sho 58-45529 is a ground in which the built-in ground of the steel pipe has a certain degree of hardness, and the ground is the earth-ground.
It is a method in which the steel pipe is pushed in with a screw for the auger to obtain a pushing reaction force with the screw for the auger. In the case of this method, there is an advantage that the steel pipe can be pushed in by obtaining the pushing reaction force from the ground excavated by the earth auger with the auger screw (anchor screw), so that the soft pipe can be pushed. The advantage can be sufficiently exerted except for the sludge layer and the sludge layer. However, in the case of mud layer or sludge layer between the topsoil and the support layer (rock bed) of the steel pipe, this technique is used as an aid.
There is a problem in that it is extremely difficult to obtain a reaction force that pushes the steel pipe with a gear.

Next, the method of Japanese Patent Publication No. 59-649 is a technical means for constructing a steel pipe in a mud layer or a sludge layer as in the present invention, and a support layer is excavated with an auger screw to form a screw. This is a method in which an anchor shaft is installed and this is used as an anchor, and a steel pipe is installed while obtaining a pushing reaction force from this. According to this method, since the excavated portion of the support layer forms a drill hole having the diameter of the screw, it is necessary to excavate a considerable depth in order to obtain the reaction force for pushing the steel pipe from the location, and the support layer is soft. There is a problem that it is necessary to excavate particularly deep in the case of a hard ground, and depending on the support layer, there are strong rocks in the middle of the planned depth, up to the depth (planned depth) necessary to obtain the indentation reaction force. For some time, it is difficult to excavate with a screw.

Further, a reaction force hole is formed in the support layer with an auger screw, the tip of the anchor is inserted into the hole, and cement is poured into the hole and solidified to obtain a pushing reaction force. However, there is a problem that it is difficult to obtain a sufficient indentation reaction force because the cement has a weak affinity with the hole of the planned depth formed in the support layer.

[Problems to be Solved by the Invention]

The problem to be solved in the present invention is as follows.
When constructing a steel pipe in a mud layer or a sludge layer, the reaction force to push the steel pipe in is reliably obtained at the planned depth of the support layer, and even if the work space at the steel pipe construction site is narrow, it can be easily constructed. It is an attempt to get the job done.

[0006]

[Means for Solving the Problems] When there is a mud layer (3) or a sludge layer (3) between the topsoil (1) and the support layer (2) in which the steel pipe is built, the support layer (2) is planned. Up to the depth (4), the drive motor (6) suspended from the arm tip (5) of the working machine is used for small-aperture grounding.
The gas (7) is rotated to form the excavation hole (8), and then the earth auger (7) is attached to the thread groove cutting tap screw for rock mass.
(16), and a screw groove (9) is formed in the rock around the excavation hole (8) of the support layer (2), and the tap screw (16) is screwed into the anchor shaft (10). Is erected to form an anchor with a built-in steel pipe. If the bedrock of the support layer (2) is soft, the thread groove cutting tap screw (16)
Uses a wide range.

Then, the upper drive motor (6) is removed, and a lot of the required length is set on the anchor shaft (10).
The first-stage steel pipe (11) is erected while excavating the topsoil (1) with the steel pipe pushing machine (12) which is used in the conventional ordinary ground with the anchor shaft as an anchor and the steel pipe (11). The excavated soil in 11) is discharged, and the steel pipe pushing machine 12 is removed from the anchor shaft 10.

Next, the second-stage, third-stage steel pipe (11 ')
(1 ″) ... are sequentially inserted into the first-stage steel pipe (11), and the steel pipe is built up to the support layer by sequentially pushing in using the conventional soft soil or sludge layer steel pipe pushing machine (13).

Next, the steel pipe pushing machine (13) is removed,
Anchor shaft (10) and thread groove cutting tap screw
Rotate (16) the drive motor (6) in the reverse direction and pull it out from the support layer (2), replace the screw groove cutting tap screw (16) with the rocker auger screw (14). -Shaft
It is attached to (10) and is drilled to the same diameter as the copper pipe in which the hole (8) previously drilled in the support layer (2) is almost built.

Next, the auger screw for rock ((1)
Anchor the mud or sludge removal device (15) instead of 4).
Attached to the shaft (10), the mud in the steel pipe or sludge (3)
To complete the steel pipe installation. Incidentally, the rotation of the anchor shaft (10) after the completion of pushing of the steel pipe may use the inner expansion type rotary reaction force device (17) to operate the working machine in the steel pipe.

[0011]

The operation of the present invention has the above-mentioned structure. The operation will be described below. Support layer
Since the excavation up to the planned depth (4) to (2) is performed with the small diameter earth auger (7), the reaction hole (8) can be easily excavated by rotating the anchor shaft (10). Further, since the hole (8) is drilled first, it is possible to easily cut the thread groove (9) on the peripheral wall of the hole (8) by the thread groove cutting tap screw (16). The screw (16) is also securely fixed to the support layer (2). If the support layer (2) is soft as bedrock, a tap groove screw tap screw to secure the reaction force.
If the blade (18) having a wide width is used, the thread groove (9) is deeply formed and a large reaction force is easily obtained.

Next, for pushing the first stage steel pipe (11),
This steel pipe (11) is to be pushed into the stable topsoil (1) of the ground, and a conventional steel pipe pushing machine (12), for example, the steel pipe building shown in JP-B-58-45529, using the anchor shaft (10) as an anchor. The device (12) is used to dig in and excavate the topsoil and remove the soil in the steel pipe (11). In this case, the pushing reaction force is of course obtained from the anchor shaft (10).

Next, a steel pipe pushing device for using the above-mentioned steel pipe pushing machine (12) in a mud layer or a sludge layer which has been present in the past, for example, in Japanese Patent Publication No. 59-649 owned by the applicant.
(13), and if the anchor shaft (10) is used as an anchor and the required steel pipes (11 ') (11 ") ... are sequentially pushed in using the modification function of the pushing direction of the device (13), the steel pipe (11 ') reaches a predetermined position of the support layer (2) and bites into the relatively soft surface layer portion (19) of the support layer by the pushing pressure, and the steel pipe (1)
The steel pipes (11 ") (11"'") are sequentially installed on the 1').

Next, the steel pipe pushing machine (13) is removed,
The anchor shaft (10) is reversely rotated by the drive motor (6) to extract the thread groove cutting tap screw (16) from the support layer, and the screw (16) is replaced with a diameter close to the inner diameter of the steel pipe. When the reaction force hole (8) is excavated by using the rock auger screw (14) having the above, the reaction force hole (8) disappears and the reaction force hole (8) is widened to a hole substantially equal to the inner diameter of the steel pipe.

In that case, the inside of the steel pipe below the topsoil layer is sludge.
Since (3) and the supporting layer are filled with the cut earth and sand, this is removed. At this time, the anchor shaft (10) may be replaced by an automatic expansion / contraction lot (20). (10) or a sludge removing device (15) that has been used in the past is used for the tip of the rod to remove sludge and earth and sand.

At the work site, especially when there is no margin in the upper space, from the tip of the working machine arm (5), the inner expansion type rotary reaction device
(17) and its central hollow rotary shaft (21) lower flange (2
The sludge removing device (15) hung on 2) is hung by the wire (29) in the steel pipe, and the expansion / contraction support (23) of the inner expansion type rotary reaction force device (17) is supplied with the fluid. It expands, and strongly presses against the inner wall of the steel pipe to take the rotational reaction force, and the sludge removal device
(15) may be gently rotated to collect and remove sludge. At this time, the hydraulic cylinder- (27) is expanded / contracted to promote the entry of sludge into the sludge removing device, and the cylinder (27) is quickly contracted to pull up the sludge removing device and operate the wire to move it outside the steel pipe. The sludge is transported and discharged from the pipe. When the work site environment is as described above, the internal expansion type rotary counter is used for the removal of the thread groove cutting tap screw (16) and the operation operation of the rock auger screw (14). It is possible to use a force device (17).

[0017]

EFFECTS OF THE INVENTION The present invention has the above-described structure and action, and therefore the thread groove cutting tap screw (16) is provided in the thread groove (9) of the reaction hole (8) formed at the planned depth of the support layer. As it is completely screwed in, unless the screw groove (9) of the reaction hole (8) collapses, a large steel pipe pushing reaction force that could not be obtained by any steel pipe building method or device of the conventional method is passed through the anchor. It has a great effect that steel pipes can be easily installed even in the soil in the mud layer or sludge layer, and since the pushing reaction force is large, the steel pipe at the bottom is Since the lower peripheral edge bites into the surface layer portion (19) of the support layer (3), a gap does not occur in the lower peripheral edge, so that sludge and water do not enter the steel pipe.

Further, according to the construction method of the present invention, since the working machine does not need a leader, the work site is small, and even when the space above the site is narrow, the arm of the small work machine can be expanded and contracted. It is possible to work, and when using the internal expansion type rotary reaction force device, even if the sky above the work site is extremely narrow,
There is an advantage that the work can be easily performed only by expanding and contracting (29).

[Brief description of drawings]

FIG. 1 is an explanatory view of excavating a reaction force hole in a support layer with a small diameter earth auger.

FIG. 2 is an explanatory view immediately before the thread groove cutting tap screw is attached to the tip of the anchor shaft and the thread groove is cut into the peripheral wall rock of the reaction hole.

FIG. 3 is an explanatory view showing a state in which a thread groove is cut on the rock wall of the reaction hole.

FIG. 4 is an explanatory view showing a state in which an anchor shaft and a thread groove cutting tap screw are screwed into a reaction force hole having a thread groove to form an anchor.

FIG. 5 is an explanatory view showing a state in which a first-stage steel pipe is built by a conventional steel pipe pushing machine using the anchor shaft as an anchor.

FIG. 6 is an explanatory view showing a state in which the first-stage steel pipe is built in the topsoil layer and the steel pipe pushing machine is removed.

FIG. 7 is an explanatory view showing a state in which the second and subsequent steel pipes are pushed in by the conventional steel pipe pushing machine into the mud layer or the sludge layer.

FIG. 8 is an explanatory view showing a state in which the pushing of the steel pipe is completed and the thread groove cutting tap screw is pulled out.

FIG. 9 is an explanatory view showing a state where the reaction force hole is cut and widened by the rock auger screw.

FIG. 10 is an explanatory view showing a state where sludge, earth and sand, water, etc. in the built-in steel pipe are being removed by a sludge removing device, and a dotted line portion indicates the position of the device when the internal expansion type rotary reaction force device is used. Indicates.

FIG. 11 is a partially cross-sectional partially omitted explanatory view showing a state in which an inner expansion type rotary reaction force device is suspended and mounted in a steel pipe, and the support body is expanded and pressure-contacted with the peripheral surface of the pipe inner wall.

FIG. 12 is a vertical cross-sectional explanatory view of the sludge removing device, showing a state in which the sludge enters the device, and the position of the valve shown by a dotted line is a position when the sludge is accommodated in the device and pulled out from the steel pipe.

FIG. 13 is an explanatory view showing a state in which the sludge inside the sludge removing device is discharged to the outside of the steel pipe.

FIG. 14 is an explanatory diagram showing a discharging method when sludge is clogged in the cylinder body of the sludge removing device.

[Explanation of symbols]

 1 surface soil 2 support layer 3 mud layer, sludge layer 4 planned deep soil 5 arm tip 6 driving motor 7 small diameter earth auger 8 reaction hole (of support layer) ... 9 screw groove (reaction) Power hole) 10 Anchor shaft 11 Steel pipe 11 'Steel pipe 11 ″ Steel pipe 12 Steel pipe indenter (for conventional ordinary ground) 13 Mud layer and sludge layer steel pipe indenter (conventional) 14 Rock rock auger screw 15 Mud or sludge removing device 16 Screw groove cutting tap screw 17 Internal expansion type rotary reaction force device 18 Tap screw blades 19 Surface layer of support layer 20 Automatic expansion rod (anchor shaft substitute) 21 Center hollow rotating shaft 22 (center) Lower flange of hollow rotary shaft 23 Expansion / contraction support 24 Fixing plate (of expansion / contraction support) 25 Drive motor (of internal expansion type rotary reaction device) 26 Reducer (of internal expansion type rotary reaction device) ) 27 Pressure cylinder- (internal expansion type rotational reaction force device) 28 Expansion / contraction connecting tube (internal expansion type rotational reaction force device) 29 Wire- (internal expansion type rotational reaction force device) 30 Cylinder body of sludge removing device 31 Sludge removal Valve of the device 32 Hollow shaft of the sludge removal device 33 Vent hole provided in the hollow shaft of the sludge removal device 34 Stop pin 35 Flange 36 Open bottom plate of the sludge removal device 37 Arrow indicating air 38 Automatic expansion rod (internal expansion reaction force Device) 39 Air hose

Claims (4)

[Claims] 1. When constructing a steel pipe in the ground where the surface soil and the steel pipe support layer are a mud layer or a sludge layer, a small diameter auger screw is drilled up to the planned depth of the support layer, and then,
The auger screw is replaced with a tap groove screw cutting screw for rock mass to form a screw groove in the excavation portion, and the tap screw is screwed into a support layer, and the tap screw and the anchor shaft are formed. With the steel pipe pushing machine used in the conventional ground having normal hardness, the first stage casing pipe is built up to a predetermined depth of the topsoil while forming an anchor with the reaction force from the support layer through the anchor. Including
Then, the earth and sand in the casing pipe are removed by an auger of the steel pipe pushing machine to complete the installation of the first stage casing pipe, and then the first stage casing pipe is installed. Second
Bring in the casing pipe of the stage and push it in with the steel pipe pushing machine, and further push the casing pipes of the third, fourth, etc. in order to push the casing pipe to the support layer, and then After rotating the anchor in the reverse direction, the thread groove cutting tap screw is extracted from the support layer, the screw is replaced with an rock auger, and a hole having a predetermined diameter is drilled in the support layer. A method for excavating steel pipes by removing the sand, water, or sludge in the sing pipe with these removal devices. 2. A support for expanding and contracting by sending and discharging a fluid is brought into close contact with the inner wall of the casing pipe to obtain a rotational reaction force, and an auger screw and a rock auger screw are obtained. The steel pipe digging method according to claim 1, wherein the steel pipe digging is performed by driving a sludge removing device or the like. 3. A thread groove cutting tap screw for rock mass used in the method for excavating a steel pipe according to claim 1, wherein a thread groove cutting edge is formed around the thread groove. 4. A support body, which expands and contracts by sending and discharging a fluid, is fixed on a fixed plate, while a drive mechanism including a drive motor and a speed reducer is provided below the fixed plate, and a hydraulic cylinder and The central hollow shaft and the expansion connecting cylinder externally fitted to the hollow shaft are connected to the fixed plate, the central hollow shaft is configured to be rotatable by the drive mechanism, and a flange is formed at the lower end of the central hollow shaft. The internal expansion type rotary reaction force device used in the steel pipe built-in excavation method according to claim 1 or 2, characterized in that the working machine in the steel pipe can be hung up.