JPH0768875B2 - Buried pipe propulsion method - Google Patents

Description

Description: [Industrial field of application] The present invention relates to a propulsion method for a buried pipe, and more specifically, when constructing an underground buried pipe such as a sewer, it is buried in the ground without excavating the ground. The present invention relates to a so-called propulsion method in which a buried pipe is sequentially propelled and buried in the formed buried hole while forming the hole.

[Conventional technology]

As a method for provoking underground buried pipes, a machine with an excavating mechanism such as an auger at the tip is used to excavate a buried hole in the ground, and then to bury the buried pipe following the excavation of the excavator. This method is called the auger method. Further, in recent years, as a material for a buried pipe used in such a propulsion method, adoption of a lightweight polyvinyl chloride pipe or a reinforced plastic pipe which does not corrode and is inexpensive has been considered.

In the conventional auger method, the buried pipe is connected to the rear of the excavator in order, and in the vertical shaft where the propulsion is started, that is, in the starting pit, the tail end of the buried pipe is pushed by the push jack etc. Was being promoted. However, in this method, all the frictional resistance force applied from the ground to the buried pipe at the time of propulsion and the excavation resistance force when excavating the ground with the excavator are transmitted to the rear through the joint between the buried pipes, and Since it concentrates on the rearmost end and opposes the propulsive force applied from the original pushing jack, extremely large pressure or stress is generated on the end face of the buried pipe, particularly on the rearmost end of the buried pipe. Therefore, if a material having a low proof stress, such as a PVC pipe, is used as the buried pipe, the buried pipe may be deformed or damaged, so that the PVC pipe or the like cannot be used. In particular, the longer the propulsion distance for continuous construction in one step, the greater the frictional resistance from the ground and the greater the pressure and stress generated at the end face and the tail end of the buried pipe. Therefore, the propulsion distance can be extended to improve construction efficiency. As the construction cost is reduced, the above-mentioned deformation or breakage of the buried pipe becomes a problem.

Therefore, as a result of researching a propulsion method that does not locally cause excessive pressure or stress at the tail end of the buried pipe, the inventors of the present invention invented the method described below, and previously proposed Japanese Patent Application No. -1832
Patent application has been filed as No. 71 etc.

In this method, a drive shaft body made of a steel pipe or the like is sequentially added to the rear of the excavator, and the rear end of the drive shaft body is pushed by a push jack to propel the excavator. Further, the embedded pipe is extended to the rear of the excavator while being inserted into the outer periphery of the drive shaft, and the embedded pipe is held and fixed to the drive shaft inside thereof. The buried pipe will be propelled together with the drive shaft body by propelling the drive shaft body. As means for holding and fixing the embedded pipe on the drive shaft, for example,
An expansion body that expands by the supply of pressurized air is installed on the outer surface of the drive shaft body, and this expansion body is expanded and pressed against the inner surface of the embedded pipe to hold and fix the embedded pipe to the drive shaft body. To be done.

In the above method, the excavating resistance force applied to the excavator is not transmitted to the buried pipe at all, and opposes the propulsive force from the original push jack via the drive shaft. In addition, the ground frictional resistance applied to each buried pipe is also transmitted to the drive shaft inside, so
All of the friction resistance of other buried pipes will not be concentrated and transmitted to the joints between buried pipes or the last part of the buried pipe row, and excessive pressure or stress may be locally generated in the buried pipes. Disappear. As a result, it is possible to use a buried pipe such as a PVC pipe having a poor yield strength in the propulsion method, and it is also possible to significantly extend the propulsion distance in one step.

[Problems to be Solved by the Invention]

However, in the conventional propulsion method, there is a method called a mud pressure method in addition to the auger method mentioned above. In this mud pressure method, the embedded pipe is held and fixed on the drive shaft body. There is a problem that the method is difficult to adopt.

The muddy water pressure construction method sends water or muddy water to the excavation point of the excavator, and excavates while pressurizing the ground surface,
It has the advantages of facilitating the excavation of the ground, preventing the collapse of the ground and the spouting of groundwater, and excavating the earth and sand discharged together with the mud, which simplifies the earth removal work. In this mud pressure method, two pipes, a mud pipe for supplying water and mud from the vertical shaft to the tip of the excavator and a drain pipe for discharging excavated earth and sand and mud, It is necessary to pass it inside.

However, as described above, when the structure in which the embedded pipe is held and fixed to the drive shaft is adopted, the holding and fixing means of the embedded pipe is installed in the space between the drive shaft and the embedded pipe. It becomes difficult to pass through the mud sending pipe and the mud discharging pipe required for the above-mentioned mud pressure application method. Generally, the mud sending pipe does not need to have a large diameter because it flows only liquid water or muddy water, but the mud discharging pipe does not need to have a sufficiently thick pipe diameter because it flows lumps of sand such as pebbles along with mud water. Must have. Therefore, it is extremely difficult to install both the mud sending pipe and the mud discharging pipe between the drive shaft and the buried pipe together with the holding and fixing means of the buried pipe.

In particular, as a means for holding and fixing the buried pipe, as described above,
When using an expander that expands with pressurized air, etc., the expander must contact over a large area of the buried pipe in order to exert sufficient friction holding force when pressed against the inner surface of the buried pipe. The volume occupied by the body becomes very large, and there is no room to install the above-mentioned mud sending pipe and mud discharging pipe. Further, in order to securely hold and fix the buried pipe, it is necessary to hold and fix the inner circumference of the buried pipe in all directions on the drive shaft body. It will be completely lost.

Therefore, an object of the present invention is to apply the mud pressure method,
As described above, by holding and fixing the embedded pipe on the drive shaft,
(EN) It is intended to provide a method for applying a structure for preventing generation of excessive pressure or stress to a buried pipe during propulsion.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, a propulsion method for a buried pipe according to the present invention includes a propulsion shaft, which is sequentially connected to a rear side of a machine and a propulsion shaft and a buried pipe held and fixed outside the propulsion shaft. In the buried pipe propulsion method in which the propulsion force is applied to the body to propel the excavator and the buried pipe into the buried hole, the excavation face plate rotatably installed at the tip of the excavator is driven by the drive source arranged in the excavator. The propulsion shaft is driven by rotation and the propulsive force is applied to the rear end side that is fixed to the excavator at the tip side.The propulsion shaft is composed of a double pipe, and one of the inner and outer ducts of the double pipe is passed through the excavator. While supplying water or muddy water to the ground and pressurizing the ground, the earth and sand excavated by the excavator is discharged backward together with the muddy water through the other pipeline.

The excavator is basically the same as the excavator employed in the normal mud pressure method. More specifically, the excavator is provided on the front surface with an excavation face plate called a cutter head for excavating the ground, a cutter disk, or a face plate.

The excavation face plate is rotationally driven by a motor or the like, and the ground is excavated as the excavation face plate rotates. In a conventional excavator, a drive source such as a motor that rotationally drives the excavation face plate is installed on a shaft or the surface of the earth, and the rotation of the drive source is transmitted to the excavation face plate inside the excavator via a drive shaft that penetrates the center of the buried hole. However, in the present invention, it is preferable to arrange the drive source inside the excavator, such as immediately after the excavation face plate. This is because, in the case of the present invention, since the propulsion shaft is used as the mud sending pipe and the mud discharging pipe, if the drive shaft is built in the propulsion shaft, the space for the pipe line is reduced. Further, if the drive source is near the excavation face plate, the drive shaft can be short. However, a power cable, a hydraulic cable, or the like for operating the motor may be connected to a shaft or a surface in the rear through a space between the propulsion shaft and the buried pipe.

The excavation face plate is provided with a soil discharge port called a slit or the like for sending earth and sand to the back, and this soil discharge port is a space that is also called a pressure chamber, a mud chamber, etc. that is sealed by a partition wall,
It is connected to a so-called intake room. A mud pipe for supplying water and muddy water and a mud pipe for discharging earth and sand and muddy water are connected to the intake chamber. By appropriately setting the amount or pressure of water or muddy water sent to the intake chamber and the amount or pressure of muddy sand or muddy water discharge, it is possible to adjust the pressure applied to the ground in front of and around the excavation face plate. it can.

In addition to the above structure, the excavator can be provided with various mechanisms and structures similar to those of a normal excavator, such as a direction correction jack for changing the excavation direction of the excavator, a laser surveying target for position measurement, and the like.

The propulsion shaft body is composed of a double pipe made of metal such as steel having a rigidity that can withstand the propulsion force from the original push jack, and two inner and outer layers of pipe lines are concentrically formed. The propulsion shaft can be connected and fixed to the rear part of the excavator with a flange or bolts, and the propulsion shafts can be connected to each other in the axial direction. As the connecting and fixing means of the propulsion shaft body, the same mechanism as the connecting and fixing means of the drive shaft body or the propulsion shaft in the usual propulsion method can be adopted. However, since water or muddy water and muddy water containing earth and sand flow through the double conduits of the propulsion shaft, it is preferable to provide a water sealing means for each conduit at the connecting portion. As the water sealing means, a sealing rubber, an O-ring, a packing, or other mechanism can be adopted as in the case of normal piping.

The tip of the propulsion shaft is fixed to the excavator, and the double pipe lines of the propulsion shaft are connected to the partition wall of the intake chamber by piping to open into the intake chamber. At the rear end of the propulsion shaft, one of the double pipes is pipe-connected to a water or muddy water supply device in the vertical shaft, etc., and the other pipe is changed from muddy water containing sediment to sediment. It is connected to a device that separates water, collects soil and recycles the separated water. The water or muddy water separated by the sediment and water separator is
It can be recycled by returning to the supply device.

Either of the inner and outer double pipe lines of the propulsion shaft may be used as the sludge pipe or the sludge pipe. Generally, it is recommended to set the sludge drainage pipe, which requires a relatively large diameter in order to flow even lumpy sediment, as the inner pipe line, and set the mud transmission pipe for flowing water or muddy water in a narrow gap as the outer pipe line. preferable. The diameter ratio of the inner and outer pipelines of the double pipe, or the distribution of the cross-sectional area can be arbitrarily determined in consideration of the above-mentioned purpose of the sludge pipe and the sludge pipe, the performance of the excavator, and the construction conditions. Can be set to.

The propulsion shaft is provided with means for holding and fixing the embedded pipe. As the means for holding and fixing the embedded pipe, if the embedded pipe is fixed so as not to move in the axial direction by making contact with the inner surface side of the embedded pipe, the fixing means for the pipe material in various ordinary mechanical devices can be applied. For example, a bag-shaped expander made of rubber or the like is provided on the outer surface of the propulsion shaft, and a pressure medium such as pressure air, oil, or water is fed into the expander to expand the expander toward the outer periphery. And press the expander against the inner surface of the buried pipe,
The embedded pipe can be held and fixed to the propulsion shaft. Further, a mechanically operated pressing plate may be pressed against the inner surface of the embedded pipe, or an engagement mechanism that engages with the inner surface of the embedded pipe and fixes in the axial direction may be provided in the propulsion shaft body. Regarding the detailed structure of the holding and fixing means of the buried pipe, the above-mentioned Japanese Patent Application No. 1-183271 and Japanese Patent Application No. 1-24
The structures disclosed in No. 0408 and Japanese Patent Application No. 63-298619 can be used.

Since the means for holding and fixing the embedded pipe is provided on the outer periphery of the propulsion shaft made of the double pipe, the space between the propulsion shaft and the embedded pipe can be freely used for installation, but the propulsion shaft and the embedded pipe can be installed. A laser beam path for surveying is preferably provided between the pipes, and a cable or a pipe for supplying power, hydraulic pressure or the like to the excavator is preferably opened.

The specific procedure and steps of the propulsion method may be basically the same as those of the propulsion method disclosed in the prior patent. That is, the propulsion shaft body covered with a buried pipe on the outer periphery and fixed by the holding and fixing means,
The excavator, the propulsion shaft, and the buried pipe are propelled by applying a propulsive force to the rear end of the propulsion shaft with a push jack while sequentially connecting and connecting the rear part of the excavator.

Then, on the rear end side of the propulsion shaft, a mud sending pipe for supplying water or muddy water is connected to one pipeline of the double pipe, and water or muddy water is supplied to the excavator through the propulsion shaft. In the excavator, the excavation face plate is rotationally driven to excavate the ground, and pressure is applied to the ground with water or muddy water supplied to the intake chamber. The excavated earth and sand is sent to the rear along with the muddy water through the other pipeline of the propulsion shaft, and is discharged to the outside through the mud pipe connected to the rear end of the propulsion shaft.

By repeating the above-described steps, the buried hole is excavated and formed by the excavator, and the buried pipes are sequentially propelled and buried in the buried hole behind the excavator. When the buried pipe is buried up to the target shaft, the excavator and propulsion shaft are disassembled and removed. With respect to the propulsion shaft, if the holding and fixing of the buried pipe by the holding and fixing means is released, only the propulsion shaft can be removed with the buried pipe left in the buried hole. After that, the post-processing work similar to the ordinary propulsion method is performed, such as appropriately treating the joints of the buried pipe and the exposed portion of the vertical shaft, and the burying work of the buried pipe is completed.

The buried pipe propulsion method according to the present invention, in addition to the above-mentioned sewer, is preferably applied to the construction of a relatively small-diameter buried pipe such as gas pipes and underground electric wire pipes. It can be used for the construction of underground pipes that it has. The material of the buried pipe is preferably a vinyl chloride pipe or a reinforced plastic pipe as described above,
It is also possible to use other tubing materials that have similar problems.

[Action]

When the embedded pipe is held and fixed to the propulsion shaft that transmits the propulsion force to the excavator, pass the mud sending pipe or drainage pipe used in the mud pressure construction method in the space between the buried pipe and the propulsion shaft. I can't.

However, if the propelling shaft is constructed of a double pipe and the two inner and outer layers of the double pipe are used for the mud sending pipe and the mud carrying pipe, the structure for holding and fixing the buried pipe is completely eliminated. It is possible to install the mud sending pipe and the mud discharging pipe without affecting.

Moreover, if the mud sending pipe and the mud discharging pipe are common to the propulsion shaft, no special piping parts or pipe connecting work is required, and the construction device can be simplified and the construction work can be streamlined.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure near the excavator at the tip of the construction apparatus used in the propulsion method of the present invention. Excavator 10
Has a cylindrical outer shape that matches the diameter of the buried hole, and is provided with the excavation face plate 20 on the front surface.

The excavation face plate 20 is provided with an excavation mechanism such as a cutter bit 21 on the front surface, and a slit-shaped soil discharge port 22 for sending the excavated earth and sand backward. The excavation face plate 20 is connected to a drive motor 26 via a drive shaft 24 provided at the center of the back surface. The drive shaft 24 is supported by a partition wall 12 that partitions the interior of the excavator 10. By the rotational drive of the drive motor 26, the excavation face plate 20 rotates, the cutter bit 21 excavates the ground,
The excavated earth and sand is taken in rearward from the soil discharge port 22. A space between the excavation face plate 20 and the partition wall 12 serves as an intake chamber 14.

The excavator 10 includes a front cylinder part 11 to which the excavation face plate 20 and the partition wall 12 are attached, and a rear cylinder part 16 for fixing a propulsion shaft body described later,
The end portions are combined in a partially overlapped state, and are connected by expandable direction correction jacks 15 provided at a plurality of positions in the circumferential direction. By changing the amount of expansion and contraction of the direction correction jack 15, the central axis of the front cylinder part 11 can be tilted in any direction with respect to the central axis of the rear cylinder part 16.
It is possible to correct 10 drilling directions. Front cylinder part 11
A sealing means 17 such as a sealing material is provided on the overlapping portion of the rear cylindrical portion 16 and
Is provided.

A propulsion shaft body 30 is fixed to a rear cylinder portion 16 of the excavator 10 via a flange connection mechanism 19. The propulsion shaft body 30 is composed of a double pipe formed of a steel pipe or the like, the outer pipe line 34 serves as a mud transport pipe for flowing water or muddy water, and the inner pipe line 32 serves as a mud pipe for flowing excavated earth and sand and muddy water. Becomes An extension pipe 84 made of a flexible hose or the like is connected to the outer surface of the outer pipe line 34 at the tip of the propulsion shaft body 30.
Is open to the intake chamber 14. Also, the inner pipeline
An extension pipe 82 is also connected to the end face of 32 and opens into the intake chamber 14 through the partition wall 12.

Another propulsion shaft body 30 is connected to the rear end of the propulsion shaft body 30, and the propulsion shaft body 30 is sequentially added rearward. FIG. 3 shows the structure of the connecting portion between the propulsion shafts 30. Double tube outer tube
At the abutting portion of 33, 33, a flange 35 having a substantially S-shaped cross section is attached to one outer pipe 33, and a flat flange 36 is attached to the outer pipe 33 facing the outer pipe 33.
Face both flanges 35, 36 and tighten with bolts 37. A seal rubber 100 is attached to a portion where the flange 35 having an S-shaped cross section and the outer peripheral surface of the other outer tube 33 are opposed to each other, thereby enhancing the water sealing performance at the joint portion of the outer tubes 33, 33. Also, at the abutting portion of the inner pipes 31, 31 of the double pipe, one inner pipe 31
A flange 38 having an L-shaped cross section is attached to the. A seal rubber 100 is also attached at a position where the flange 38 and the outer peripheral surface of the other inner pipe 31 face each other, and the inner pipe line 32 and the outer pipe line 3 are attached.
We are trying to cut off the water seal with 4.

On the outer periphery of the propulsion shaft body 30, a holding and fixing means 40 for the buried pipe is attached. As shown in FIG. 4, holding and fixing means
40 is made of an elastic material such as rubber and is composed of an annular tube-shaped expander 42 having a flat oval cross section and a support member 44 that supports the expander 42 and fixes it to the propulsion shaft 30. ing. A supply pipe 46 for sending pressurized air is connected to the expander 42. When the expander 42 is filled with pressurized air, the expander 42 expands to the outer peripheral side, and the outer surface of the expander 42 is pressed against the inner surface of the embedded pipe 70 made of a vinyl chloride pipe or the like. When the expander 42 is pressed against the buried pipe 70, the buried pipe 70 and the expander 42
Due to the frictional support force acting between the
That is, 42 is held and fixed to the propulsion shaft body 30. Since the expander 42 elastically abuts the embedded pipe 70, the embedded pipe 70
There is no need to worry about scratching or local deformation. When the compressed air filled in the expansion body 42 is released, the expansion body 42 contracts toward the inner peripheral side, so that the holding and fixing to the embedded pipe 70 is released.

As shown in FIG. 4, the support member 44 of the holding and fixing means 40 is
Cylinder face plate 43 with expander 42 attached and cotton swab 43 are propelled shaft 30
The end plate 48 supports the target space 45 for laser surveying and the space for inserting the cable piping.
47 is formed through. Laser survey means that a laser surveying device installed at the end of the buried pipe 70 in a shaft or the like emits laser light toward the excavator 10 and is reflected by a target (not shown) provided in the excavator 10. The generated laser light is again detected by the laser surveying device to measure the position of the excavator 10, that is, the bending and inclination of the buried hole. The target space 45 secures a laser optical path. In the space 47 for inserting the cable pipe, the drive motor 26 of the excavator 10
A power cable for supplying power and hydraulic pressure, hydraulic piping, and the like are passed through the direction adjusting jack 15 and other mechanical parts.

The holding and fixing means 40 may be provided on all of the propulsion shafts 30 that are added to the front and the rear, or the holding and fixing means 40 may be provided on a plurality of propulsion shafts 30. A part of the tip of the buried pipe 70, which is held and fixed to the foremost propulsion shaft body 30, is an excavator.
It is inserted inside the rear tube portion 16 of the casing 10. The holding and fixing means 40 arranged on the plurality of propulsion shafts 30 can be constructed by making the plurality of holding and fixing means 40 actuate or deactivate at the same time by making the supply pipe 46 for the compressed air common. It is easy to release and hold the embedded pipe 70 later and disassemble and remove the propulsion shaft body 30.

As described above, the propulsion shaft body 30 and the buried pipe 70 are sequentially added to the rear of the excavator 10. Then, as shown in FIG. 2, in the rearmost propulsion shaft body 30a, the outer pipe line 34
On the outer surface of the pipe, mud pipes connected to the water or mud supply device
94 is connected. The inner pipe line 32 penetrates the outer pipe line 34, extends to the outside of the propulsion shaft body 30, and is connected with a sludge discharge pipe 92 connected to a device for separating soil and muddy water or the like. Propulsion shaft
At the rear end of 30a, a source push jack 50 is provided via a wheel 52. The source push jack 50 is supported by the fixed wall 60 of the vertical shaft and expands and contracts forward to apply a propulsive force to the propulsion shaft body 30a.

When the propulsion shaft body 30a is propulsively moved, the mud sending pipe 94 and the mud discharging pipe 92 also need to be moved. Therefore, it is preferable that both pipes 92, 94 are formed of flexible hoses or the like so that they can be expanded and contracted. . The rearmost propulsion shaft 30a is propelled by a certain distance, then the original push jack 50 is contracted to return the propulsion shaft 30a to the original position, and the rearmost propulsion shaft 30a and the propulsion shaft 30 in front of it. Another new propulsion shaft 30
Are inserted, and the propulsion shafts 30 are added one after another. By doing this, the mud sending pipe 94 and the mud sending pipe 92
Is attached to the rearmost propulsion shaft 30a,
Zero propulsion and replenishment connection work can be performed.

A method of performing propulsive embedding of the embedding pipe 70 using the above-described device will be described. First, the excavator 10 is horizontally propelled while excavating the ground from the side wall in the vertical shaft that is the starting shaft. The embedded pipe 70 is individually covered on the propulsion shaft 30 and fixed to the propulsion shaft 30 by the holding and fixing means 40. The propulsion shaft body 30 in which the buried pipe 70 is held and fixed is connected to the rear portion of the excavator 10, and the inner and outer conduits 32 and 34 of the propulsion shaft body 30 are connected to the excavator 10 and the rearmost propulsion shaft body 30a. It is possible to supply water or muddy water to the machine 10 and to discharge the excavated earth and sand together with the muddy water to the rear.

The ground is excavated by the excavator 10 to form a buried hole, and a propulsion force is applied to the rearmost propulsion shaft 30a by the original pushing jack 50, whereby the excavator 10 and the propulsion shaft 30 and the buried pipe 70 are integrated. And is propelled into the buried hole. When excavating the ground, the intake chamber 14 of the excavator 10 is filled with water or muddy water and applies a certain pressure to the ground in front, so the ground will not collapse or groundwater will not spout. . The excavated earth and sand are discharged to the rear along with mud.

When one set of the propulsion shaft 30 and the buried pipe 70 is propelled into the ground, another new propulsion shaft 30 and the buried pipe 70 are added, and the same process as above is repeated. When the excavator 10 reaches the intended vertical shaft, the excavator 10 is disassembled and removed from the rear propulsion shaft 30. If the buried pipe 70 is buried in the entire length of the buried hole,
The holding and fixing of the embedded pipe 70 by the propulsion shaft 30 is released, and the embedded pipe 70 is released.
Only the propulsion shaft body 30 is disassembled and removed while leaving 70 in the buried hole. In this way, the propulsion burial construction of the buried pipe is completed.

〔The invention's effect〕

According to the propulsion method for the buried pipe according to the present invention described above, the buried pipe can be held and fixed to the propulsion shaft so that excessive pressure or stress is not locally generated in the buried pipe, at the same time, It is possible to apply a so-called muddy water pressure type propulsion method, in which water or muddy water is supplied to the excavator and the excavation is performed with a certain pressure being applied to the ground.

That is, since the propulsion shaft is composed of a double pipe, and the inner and outer two layers of the double pipe are used as the mud sending pipe and the mud discharging pipe, the embedded pipe is held and fixed to the propulsion shaft. The functions of the mud sending pipe and the mud discharging pipe can be exerted without affecting the structure and arrangement of the means at all. Moreover, since it is not necessary to separately install the mud sending pipe and the mud discharging pipe, it is possible to save the labor of the piping work and to prepare the piping parts separately, so that the equipment cost and the construction cost can be reduced.

As a result, the advantage of the mud pressure method is that it can prevent ground collapse and groundwater spouting well, that excavation efficiency is improved, and that excavated earth and sand can be discharged efficiently. It is possible to satisfactorily exert any of the advantages of the method of holding and fixing the above-mentioned to the propulsion shaft body, that is, the point that excessive pressure or stress is not applied to the buried pipe.

Therefore, it was possible to use a pipe material with poor yield strength such as a PVC pipe, which was extremely difficult in the conventional mud pressure method, or to perform long-distance continuous propulsion, which is not possible in the conventional method. It is possible to improve the construction efficiency of the propulsion method, improve the corrosion resistance of the buried pipe, or significantly reduce the construction cost.

[Brief description of drawings]

FIG. 1 is a sectional view showing a tip portion of a construction device for carrying out the propulsion method of the present invention, FIG. 2 is a sectional view showing a rear end portion, and FIG. 3 is an enlarged sectional view showing an essential portion showing a connecting portion of a propulsion shaft. Figure, 4th
The drawing is an enlarged cross-sectional view in a direction orthogonal to FIG. 10 …… excavator, 30 …… propulsion shaft, 32 …… inner conduit, 34…
… Outside pipe, 40 …… Holding and fixing means, 50 …… Original jack, 70 …… Buried pipe

Claims (1)

[Claims] 1. An excavator and a buried pipe by applying a propulsive force to the propulsion shaft while successively adding a propulsion shaft and a buried pipe held and fixed on the outside of the propulsion shaft to the rear of the excavator. In the propulsion method of the buried pipe that propels the digging hole into the burial hole, the excavation face plate rotatably provided at the tip of the excavator is rotationally driven by the drive source arranged in the excavator, and the tip side is fixed to the excavator. The propulsion shaft to which the propulsive force is applied is composed of a double pipe, and water or muddy water is supplied to the excavator through one of the inner and outer pipe lines of the double pipe while pressurizing the ground. , A propulsion method for buried pipes, characterized in that the earth and sand excavated by an excavator is discharged backward together with mud through the other pipeline.