JP2001311386A - Excavating device and jacking method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately execute a steep curve by effectively utilizing apparatuses such as jacks without conducting complicated work. SOLUTION: A curve shaping device 20 is connected between an excavating machine 10 provided with an excavating means 15 at the tip and formed with a plurality of shell bodies 12 and a flexible advance pipe 40 connected with concrete tube bodies 41 and cushion materials 42 in turn. The curve shaping device 20 has a plurality of tube bodies 21 each having the length L2 shorter than that of the shell body 12 in series, a plurality of pressing jacks 22 are provided between adjacent tube bodies 21 to freely expand joint openings, and the pressing jacks 22 are annularly arranged along the peripheral faces of the tube bodies 21. The curve shaping device 20 and the flexible advance pipe 40 are removably connected together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digging device and a propulsion method capable of suitably performing a long-distance sharp curve in a propulsion method for propelling a pipe underground.

[0002]

2. Description of the Related Art The propulsion method refers to a method in which a plurality of propulsion pipes such as fume pipes are sequentially added in series from the rear, starting from an excavation machine for excavating the ground starting from a starting shaft, and the tail end of the excavation machine is located in the shaft. By pushing in with the original push jack,
This is a method of laying the plurality of propulsion pipes underground. In this propulsion method, "linear push" is basically performed in which a plurality of propulsion pipes are added in series and propelled while bringing end faces perpendicular to the pipe axes into straight contact. However, today, the demand for curve construction by the propulsion method has been increasing, and efforts for the technology have been progressing.

[0003] In the curved construction, the end faces of the adjacent propulsion pipes bent along the curved line are opened in a wedge shape in plan view. In this state, stress concentration occurs on the end face of the propulsion pipe, causing pipe breakage, and the direction of thrust transmission is not determined, and unexpected and inaccurate curvature curves are likely to occur. In the conventional curve construction, such a problem has been solved by various means. Hereinafter, the conventional curve construction will be briefly described.

[0006] A camper, such as a small jack or a small piece of wood, is inserted into a perforated portion (gap) of an end face of an adjacent propulsion pipe bent along a curve, and a predetermined hole is inserted through the camber. This is a method of maintaining the opening and transmitting the thrust. But,
Although this method has been tried for a long time, it has become obsolete today due to the complexity and uncertainty of the construction. The method of installing a hydraulic jack (ram jack) over the entire length of the curve is rational for transmitting thrust and securing appropriate openings, but has disadvantages such as an increase in cost due to expensive equipment and complicated construction. .

[0005] Cushion material insertion method (Sempra curve system) A cushion material is inserted between the end faces of adjacent propulsion pipes, and on a curve, a trajectory excavated by a drilling machine (dig hole)
The following propulsion tube will follow. In the curve, the cushioning material is deformed according to the bending angle between the adjacent propulsion pipes, and the thrust transmitting area is secured. Since the direction control of the excavating machine is performed using the reaction force of the side ground, in many cases, the strength of the ground is reinforced by injecting a chemical solution etc. to obtain the reaction force on the side of the excavating machine . This method of inserting a cushioning material has become a mainstream method of today because it has a simple structure and requires no effort. However, while effective and rational for gentle curve construction, thrust transmission area cannot be ensured for sharp curve construction, and pipes are broken or the size of openings varies. In addition, it is difficult to construct a curve in both the X and Y axes.

Unit Curve Method This is a method disclosed in Japanese Patent Publication No. 1-56240. In this method, a plurality of opening adjusting members (direction-correcting jacks) are arranged side by side in the pipe circumferential direction between adjacent propulsion pipes. The construction of the curve is performed by making a difference between the stroke lengths of the plurality of opening adjustment members and bending the adjacent propulsion pipes. The bending of the propulsion tube controls the direction of the excavating machine. This construction method can cope with a sharp curve construction to some extent as compared with the above construction method, and can construct a curve of both X and Y axes. However, there is a problem that a large number of jacks must be used.

[0007]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention has been made in consideration of the above circumstances, and has been described as being capable of performing a sharp curve construction accurately and economically with effective use of jacks and other equipment without complicated work. The purpose is to provide equipment and propulsion methods.

[0008]

In order to achieve the above object, according to the present invention, there is provided one or more shells (12) arranged in series in the propulsion direction and the shell at the head of the propulsion direction. An excavating machine (10) provided on a body and having an excavating means (15) capable of excavating a ground in front thereof;
(1) a flexible propulsion pipe (40) which is formed by alternately connecting a flexible ring (42) and a flexible ring (42) in a propulsion direction in series and which is disposed behind the excavating machine. The directional stabilizer (20) behind the excavating machine
The direction stabilizing device comprises a cylinder (2) having a length (L2) in the propulsion direction shorter or equal to the length of the shell.
1), a plurality of jack means (22) are arranged in series in the propulsion direction, and a plurality of jack means (22) are provided between the cylinders adjacent in the propulsion direction.
Each of the jack means is provided so as to be able to open and close between the cylinders, and a plurality of jack means between the cylinders adjacent to each other in the propulsion direction are arranged along the peripheral surface of the cylinder, and the rear of the direction stabilizing device. Wherein the flexible propulsion tube is detachably connected.

According to a second aspect of the present invention, the length (L3) of the direction stabilizing device in the propulsion direction is longer than the first shell in the propulsion direction.

According to a third aspect of the present invention, the jack means is a hydraulic jack, and a pressure measuring section (60) for measuring a pressure acting on the hydraulic jack is provided, based on a result of measurement by the pressure measuring section. And an information output section (61, 62) for outputting information on the excavation state.

According to a fourth aspect of the present invention, a cylindrical collar member (21b) is provided between the adjacent cylinders in the propulsion direction so as to cover a gap between the cylinders. It is characterized by being formed of a flexible material.

According to a fifth aspect of the present invention, the jack means is a hydraulic jack, and hydraulic oil can be freely moved between two or more jack means among the plurality of jack means. A hydraulic oil distribution means (100) for causing the hydraulic oil to flow is connected.

According to a sixth aspect of the present invention, a propulsion pipe (4) is provided from the rear of an excavating machine capable of excavating the ground in the forward direction.
0, 50) are sequentially added and pushed in, and in the propulsion method of excavating the ground by the excavating machine and laying the propulsion pipe subsequent to the excavating machine on the ground, the excavation machine and the propulsion pipe are interposed. In the propulsion direction, a bendable cylindrical direction stabilizing device having a plurality of joints in the propulsion direction is connected, and when performing the curve excavation by the excavating machine, the direction stabilizing device is adjusted to the curvature of the curve to be excavated. The propulsion method according to claim 1, wherein the excavating machine is adjusted to the curvature by using the direction stabilizing device as a guide by bending the excavating machine.

According to a seventh aspect of the present invention, in the propulsion method according to the sixth aspect, a flexible propulsion pipe formed by alternately connecting a concrete pipe and a flexible ring member in a propulsion direction in series is provided. Connected to the back of the stabilizer, when performing the curve excavation by the excavating machine, the flexible propulsion pipe is bent and introduced into the already curved excavation hole (r), and the posture of the flexible propulsion pipe is changed to By holding the drilling hole in alignment with the drilling hole, the drilling machine, the directional stabilizing device, and the flexible propulsion pipe, which hold the posture in accordance with the curvature of the curve to be drilled, stabilize the drilling direction by the drilling machine. It is characterized by taking measures.

In the present invention, the excavation means (15) excavates the ground in the forward direction of the propulsion direction, and successively adds and pushes the propulsion pipe (50) from the back, thereby excavating the ground of the propulsion pipe. In the propulsion method of performing propulsion and laying, a cylindrical direction stabilizing device (20) having a plurality of joints arranged in a propulsion direction is installed between the excavation means and the propulsion pipe, and When performing curve excavation, the joint is connected so that thrust can be transmitted at the outer peripheral position of the curve to be excavated, and the joint is set to be contractible at the inner peripheral position of the curve to be excavated, thereby performing excavation. The thrust transmitted at the outer peripheral position of the curve to be generated and the reaction force received from the ground by the excavation means generate a couple, and the excavation propulsion direction of the excavation means is changed to the ground reaction force outside the curve by the couple force. A jacking method for causing change to match regardless curvature of the to be excavated curve.

According to a ninth aspect of the present invention, in the propulsion method according to the eighth aspect, the joint is provided with a ram (2) in a propulsion direction.
2a) jack means (22) that can be driven are arranged at the outer peripheral position and the inner peripheral position of the curve to be excavated, respectively.
At the outer peripheral position of the curve to be excavated, the ram of the jack means is protruded to connect the joint so that thrust can be transmitted, and at the inner peripheral position of the curve to be excavated, the ram of the jack means is retracted to form the joint. Is set to be contractible.

In the present invention, claim 10 is claim 9
In the propulsion method, when performing a curve excavation by the excavating means, the tip of the ram of the jack means is brought into contact with an adjacent portion in the joint at an outer peripheral position of the curve to be excavated, and A clearance is formed between an end of the ram of the jack means and an adjacent part of the joint at an inner peripheral side position.

Note that the numbers in parentheses are for convenience showing corresponding elements in the drawings, and therefore, the present description is not limited to the description on the drawings.

[0019]

According to the first and sixth aspects of the present invention, when performing a curve excavation with an excavating machine, the direction stabilizing device is bent via the jack means in accordance with the curvature of the planned curve to be excavated. Thus, the orientation of the excavating machine is adjusted to the curvature using the direction stabilizing device as a guide. By bending the multi-joint direction stabilizing device constituted by a plurality of cylinders, the direction stabilizing device can be in close contact with the ground wall surface of the excavation hole formed along the planned curve, and suitably follows the curve. . This is particularly effective because the length of the cylinder is shorter than the shell. in this way,
Since the directional stabilizer is stably propelled along the planned curve, the posture of the excavating machine to which the thrust is transmitted via the directional stabilizer, and therefore the excavation direction, is stabilized, and the directional stabilizer may be accidentally deviated from the planned curve. That is prevented. That is, according to the present invention, the construction of a long-distance sharp curve can be performed accurately.

Further, in the first and seventh aspects of the present invention, the flexible propulsion pipe that follows the direction stabilizing device is appropriately bent and introduced into the excavated hole that has been dug accurately along the planned curve. There is no need to perform any complicated work. Further, in the flexible propulsion pipe, in the planned curve, the flexible ring material is deformed according to the bending angle between the concrete pipe bodies. The flexible ring material is mainly compressed on the inner circumferential side of the planned curve, and then the compression of the thin portion converges, and the outer circumferential side of the planned curve extends from that point as a starting point. When the movement of the thrust transmitting position is completed in this way, the flexible propulsion pipe does not inadvertently lose its posture, the thrust transmitting position is balanced, and there is no behavior such as bulging to the outer peripheral side of the planned curve. In other words, due to such a property of the flexible propulsion pipe, in the curve construction, the excavating machine, the direction stabilizing device and the flexible propulsion pipe are integrated into three members to maintain a posture according to the planned curve, and to be stabilized by accurate thrust transmission. Excavation direction can be maintained.

According to the first aspect of the present invention, the detachable directional stabilizer can be removed from the propulsion pipe after completion of the propulsion work and collected, and can be reused at another construction site. The equipment including the equipment can be effectively used without wasting, and low-cost construction is realized.

According to the second aspect of the present invention, since the length of the directional stabilizer is longer than the shell at the head of the excavation, the wall contact area for obtaining the directional control reaction force against the shell is directionally stabilized. It can be obtained in an apparatus and can realize an accurate excavation direction in curve construction.

The third aspect of the present invention has the following effects. That is, if the excavating machine deviates from the planned curve, a borehole having a curvature different from the planned curve is formed, and a subsequent directional stabilizer is introduced into the borehole. Since the bending state of the directional stabilizer is adjusted to the curvature of the planned curve, pressure is exerted on each jack means of the directional stabilizer when the excavation hole is introduced by the force from the ground. Therefore, by measuring the pressure and outputting information on the digging state based on the measurement result, that is, information that the digging is out of the planned curve, a deviation from the planned curve is quickly detected, and This is convenient because corrections and the like can be taken.

According to the fourth aspect of the present invention, since the collar member is formed of a flexible material, it does not jump up following the deformation of the cylinder connecting portion even if the space between the cylinders is bent. And do not contact the ground. As a result, resistance during propulsion is less likely to occur, and smooth propulsion can be achieved even during curve construction. Of course, the invasion of earth and sand is prevented by the collar member, and a water stopping effect can be obtained.

According to a fifth aspect of the present invention, the hydraulic oil (pressure oil) generated by the hydraulic unit is supplied in parallel from one switching valve to two or more jack means. Therefore, when setting the aperture between the adjacent cylinders, it is possible to ensure the synchronism of the reaction force generated in the jack means connected by the hydraulic oil distribution means.

In the present invention, a couple is generated by a thrust transmitted at a position on the outer peripheral side of a curve to be excavated and a reaction force received by the excavating means from the ground, and the couple is generated by the couple. Excavation direction easily (naturally) according to the curvature of the curve to be excavated without depending on the ground reaction force outside the curve
Since it can be changed, sharp curve construction can be performed easily and accurately.

According to claims 9 and 10 of the present invention,
The excavation propulsion direction can be easily controlled by utilizing the retraction of the ram by the jack means.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of a digging device according to the present invention. As shown in FIG. 1, the excavating device 1 used in the propulsion method is at the top (left side in FIG. 1).
Thus, the excavating machine 10, the curve shaping device 20, the pipe circumference mixing device 30, and the flexible propulsion pipe 40 are connected in series in this order in the propulsion direction (the arrow X direction in FIG. 1). Further, a plurality of fume tubes 50 are connected in series to the rear end of the excavating device 1, that is, the rear end of the flexible propulsion tube 40.

The excavating machine 10 according to the present embodiment is the same as a conventionally used excavating machine of the half-fold split-body type (for example, a semi-shield machine φ1500). That is, as shown in FIG. 1, the excavating machine 10 is configured by connecting a plurality (in the present embodiment, four, but any number) of units 11 (11A, 11B, 11C, 11D) in series in the propulsion direction. Each unit 11 has a cylindrical shell 12 having substantially the same length L1 (length in the propulsion direction). However, the units 11 may have different lengths.

The head unit 11A has, at the front of the shell 12 (left side in FIG. 1), a digging means 15 having a cutter or the like capable of digging the ground in front. Unit 11
In the shells 12 of A, 11B, and 11C, a plurality of middle bent jacks 13 are provided annularly along the peripheral surface of the shell 12, and the ram side of these middle bent jacks 13 is adjacent to the rear side. The shell 12 of the unit 11 is disposed so as to be freely pressed in the propulsion direction. That is, the bending state of the plurality of units 11 can be adjusted by appropriately adjusting the stroke of the middle folding jack 13.

FIG. 2 is a plan view (partially sectional view) of the curve forming device 20. A curve forming device 20 that is a curve forming device for easily forming a desired curve and is also a direction stabilizing device for stabilizing an excavation direction along the curve after the curve forming is illustrated in FIGS. 1 and 2. As described above, the plurality of units 25 connected to the last unit 11D of the excavating machine 10 and arranged in series in the propulsion direction.
(25A, 25B, 25C, 25D). Each unit 25 has a cylindrical body 21 which is a steel cylindrical body, and the distal end side (the left side in FIG.
1a, a rear end side (right side in FIG. 2) is a collar portion 21b. That is, the insertion part 21a of each cylinder 21 is inserted into the collar part 21b of the cylinder 21 adjacent to the front,
The insertion portion 21a of the cylinder 21 adjacent to the rear is inserted into the collar portion 21b of each cylinder 21.

Since the cylinder 21 is made of steel, the cylinder 2
1 makes it possible to form the curvilinear shaping device 20 by shortening the length in the propulsion direction as much as possible (even if it is shortened, it is more resistant to breakage than concrete). As described below,
By shortening the length of the cylindrical body 21 as much as possible, the curve forming device 20 that can cope with a sharp curve is provided. However, if problems such as strength can be cleared, the cylinder 21
Instead of steel, it may be formed of plastic, concrete, or the like.

In this embodiment shown in FIG. 2 and the like, the cylindrical collar portion 21b is formed integrally with the cylindrical body 21. However, it is also possible to form the collar portion 21b separately from the cylindrical body 21 and to form the collar portion 21b with a flexible material such as rubber.

FIG. 3 is a diagram showing the arrangement of the pressing jack in the cylinder. Each unit 25 includes a plurality of pressing jacks 22 composed of hydraulic jacks as shown in FIGS.
Are arranged in an annular shape along the peripheral surface of the cylindrical body 21, and each pressing jack 22 has the cylinder side of the cylindrical body 2.
Fixed to 1. The ram 22a of each pressing jack 22 is connected to the cylindrical body 2 to which the pressing jack 22 is fixed.
1 is arranged toward the front end side, and is configured to be able to protrude and retreat in the axial direction. In each cylinder 21, a pressure receiving wall 23 having a wall surface perpendicular to the propulsion direction formed toward the rear is provided along the inner periphery of the cylinder 21, and behind the cylinder 21. The ram 22a of the pressing jack 22 provided on the adjacent cylinder 21 can freely contact the wall surface of the pressure receiving wall 23.

In this embodiment, as shown in FIG. 3, the number of pressing jacks 22 of each cylindrical body 21 is eight (or may be eight or more. Needless to say, if the curve to be constructed is not tight, the pressing jacks 22 may be used). The number of pressing jacks 22 may be less than eight, for example, four.), And these pressing jacks 22 are symmetrically arranged about the center axis CT of the cylindrical body 21. Further, in the present embodiment, the pressing jack 22 is arranged with the ram a side facing forward, but the pressing jack 22 may be installed so as to be able to open and close between the front and rear adjacent cylindrical bodies 21, so that the ram 22 a It may be arranged with the side facing backward.

Further, as shown in FIG. 2, the pressure jack 22 is provided with a pressure measuring section 60 for measuring the oil pressure, and the pressure measuring section 60 performs an operation for performing a predetermined operation on the measurement result. The unit 61 is connected. Also, a display means 62 such as a monitor for displaying and outputting the calculation result is connected to the calculation section 61. The pressure measuring unit 60
May measure the pressure acting on the pressing jack 22 by a method other than the oil pressure measurement.

The curve forming apparatus 20 shown in the example of FIG. 2 has six units 25 having the above-described configuration, and these are functionally distinguished into two types of units 25A and 25B. That is, the second, third,
The fifth and sixth units 25 are unit 25A, FIG.
The fourth and seventh units 25 from the left side of the drawing are units 25B. The length L2 of the cylinder 21 of the units 25A and 25B in the propulsion direction is sufficiently smaller than the length L1 of the shell 12 of the excavating machine 10 (L2 is approximately half of L1) (however, the cylinder 21 The length L2 of the shell 12
Can be made equal to the length L1. ).

The first (leading) unit 25 from the left in FIG. 2 is a special unit 25C. Since this unit 25C is for connection with the excavating machine 10, the pressing jack 22 is provided. However, the tip side is inserted into the unit 11D of the excavating machine 10. The eighth (last) unit 25 from the left in FIG.
Is also a special unit 25D.
5D is for connection with a pipe mixing device 30 to be described later, and the distal end side of the pipe 31 of the pipe mixing device 30 is inserted into the collar portion 21b.

The unit 25A described above is a unit 25A.
A unit 25A or a unit 25B can be connected behind any unit 25A except for the unit 25A. The unit 25B can be connected only to the rear of the unit 25A, and the unit 25A is connected to the rear of the unit 25B.
Alternatively, the unit 25D can be connected. As a result, in the example of FIG. 2, the second, third, and fourth units 25A, 25A, and 25B from the left in FIG.
7 is another set 27 by the fifth, sixth, and seventh units 25A, 25A, and 25B from the left in FIG.
Is configured. That is, by connecting one or more sets 27 in an arbitrary number between the units 25C and 25D according to the situation, the length L in the propulsion direction of the curvilinear shaping device is obtained.
3 (see FIG. 1) can be easily adjusted.
Note that the length L3 of the curve forming device 20 in this embodiment is sufficiently longer than the length L1 of each shell 12 of the excavating machine 10 (the length L3 depends on the curvature of the curve to be constructed). Although it is determined, 2 to 4 m is assumed in the present embodiment).
However, it is also possible to make the length L3 of the curve forming device 20 equal to or less than the length L1 of the shell 12 depending on soil conditions and the like.

On the other hand, the pipe mixing apparatus 30 is the same as a pipe mixing apparatus conventionally used as shown in FIG. That is, the pipe circumference mixing apparatus 30 has a cylindrical pipe 31 connected to the last unit 25D of the curve forming apparatus 20, and the pipe 31 has the pipe 31
A large number of injection holes 32 communicating with the inside and outside of the tube wall are formed over the entire circumference. The inside of the tube 31 is filled with a lubricant supplied from a lubricant injection plant (not shown) installed on the ground to the outside of the tube 31 through the injection hole 32 so as to be freely injected into the ground. A not-shown lubricating material supply means such as a pipe is provided. Therefore, the pipe mixing device 30 can inject a lubricant such as bentonite liquid between the pipe body 31 and the ground through a large number of injection holes 32, and thereby the flexible mixing device 30 following the pipe mixing device 30 can be injected. The frictional force between the propulsion pipe 40 or the fume pipe 50 and the ground can be reduced.

It should be noted that the pipe peripheral mixing device 30 has a
As disclosed in Japanese Patent Application No. 12594 (Japanese Utility Model Application No. 5-47151) and the like, a rotary cutting body provided with a bit capable of cutting a lubricant injection tail void on the outer periphery of a pipe body has a predetermined rotation angle. It is also effective to use a "friction reducing device" provided rotatably forward and backward. This further reduces the frictional resistance with the ground.

FIGS. 4A and 4B are views showing a flexible propulsion pipe, in which FIG. 4A is a side perspective view, FIG. 4B is a plan sectional view of a pipe wall, and FIG. 4C is a perspective view showing only a cushion material. FIG. The flexible propulsion pipe 40 is similar to a known SR propulsion pipe (curved propulsion pipe) as shown in FIGS. For example, this SR propulsion pipe is Vol.13, No.8,
This is described in detail in "Monthly Propulsion Technology" in 1999, such as "Site Report, Sewer Propulsion Technology Active in Various Fields, Development of Steep Curve Propulsion Pipe for Large and Medium Diameters". That is,
1 and FIG.
As shown in (a), a large number of annular concrete pipes 41 and annular cushion members 42 are connected in such a manner that they are alternately arranged in the propulsion direction. The length L4 of the concrete pipe 41 in the propulsion direction is sufficiently smaller than the length L1 of each shell 12 of the excavating machine 10.

The cushion member 42 is a flexible member formed of a hard polyvinyl chloride resin or the like. Also, as shown in FIGS. 4B and 4C, the thickness W of the cushion material 42 is thicker on the left and right than on the upper and lower sides (FIG. 1 and FIG. And different). That is, it can be greatly deformed on the left and right. Further, between the concrete pipes 41, 41 adjacent via the cushion member 42, a steel cylindrical collar 43 (a flexible member instead of a steel collar) is provided so that the cushion member 42 is not exposed. (A color 43 is omitted because FIGS. 1 and 4A are simplified displays). However, color 43
A flexible rubber 45 provided along the outer periphery of each concrete pipe 41 is interposed between the concrete pipe 41 and the concrete pipe 41. That is, by the collar 43 and the flexible rubber 45,
The adjacent concrete pipes 41, 41 can exhibit an appropriate bending rigidity.

Note that the flexible propulsion pipe 4 in this embodiment is
0 is divided into a plurality of units 46 each having a predetermined length that can be sequentially added to and propelled from a starting shaft (not shown). For example, FIG. 1 shows an example including two units 46 and 46. . How many units the flexible propulsion pipe 40 is composed of depends on the length of the curved portion to be constructed and the like. In the completed state, the number of the units 46 is selected so that the flexible propulsion pipe 40 can be arranged at least in the curved portion.

The flexible propulsion pipe 40 of the excavating device 1
At the rear end, as shown in FIG. 1, a plurality of fume tubes 50 conventionally used as propulsion tubes are arranged in series so as to be able to transmit a propulsion force in a propulsion direction. The length L5 of each fume tube 50 in the propulsion direction is substantially the same as the length L1 of each shell 12 of the excavating machine 10 and the length L2 of each cylinder 21 of the direction stabilizing device 2 and the concrete length of the flexible propulsion tube 40. It is sufficiently longer than the length L4 of the tube 41.

Since the excavating device 1 and the fume pipes 50 and the like following the excavating device 1 are configured as described above, pipe laying work including a long-distance steep curve is performed by the propulsion method using the excavating device 1 described below. Become like 6 to 9 are schematic views showing the procedure of the sharp curve construction.

First, the excavating machine 10 is horizontally pushed into the ground from a starting shaft (not shown) by a main pushing jack (not shown). At this time, the front ground of the excavating machine 10 is excavated through the excavating means 15 so that the excavating machine 10 is propelled into the ground. Subsequently, a curve forming device 20 is connected to the rear end of the excavating machine 10,
This is pushed and propelled toward the ground by a main push jack (not shown). Subsequently, the pipe mixing device 30 is connected,
Subsequently, the units 46 of the flexible propulsion pipe 40 are sequentially added to each other and propelled to the ground. A predetermined number of units 46 are added and the entire flexible propulsion pipe 40 is propelled, and subsequently the fume pipes 50 are propelled to the ground while being sequentially added.

In this state, since only the straight propulsion is still performed, the excavating machine 10, the curvilinear shaping apparatus 20, and the flexible propulsion pipe 40 are all linear in the whole state (the same as the state in FIG. 1). ). Subsequently, the excavating device 1 is propelled until the tip of the excavating machine 10 reaches the change point P as shown in FIG. This change point P is the start point of the planned curve R that is a long-distance sharp curve. In addition, a large number of injection holes 32
Since the lubricating material is injected into the ground side from below, the flexible propulsion pipe 40 and the fume pipe 50 following this are reduced in friction with the ground and are smoothly propelled.

Further from the state shown in FIG. 6, a fume tube 50 is added and pushed from a starting shaft (not shown) to propel the excavating device 1 forward. At the time of this propulsion, the excavating machine 10 adjusts the strokes of the plurality of bent jacks 13 of the unit 11 that are about to enter the planned curve R, for example, so that the outer-side stroke is larger than the inner-side stroke. The unit 11 is bent with respect to the subsequent unit 11. As a result, each unit 11 of the excavating machine 10 bends and propells sequentially, and as a result, FIG.
The entire excavating machine 10 is propelled along the planned curve R as shown in FIG.

In the state shown in FIG. 7, the tip of the curve forming device 20 has reached the change point P, and the fume tube 50 is further added from the starting shaft (not shown) and pushed in by pushing the excavating device 1 forward from the state shown in FIG. Promote. At the time of this propulsion, in the curve shaping device 20, in the unit 25 adjacent to the rear side of each unit 25 that tries to enter the planned curve R,
The strokes of the plurality of pressing jacks 22 are adjusted. In addition, since the excavating machine 10 is completely shifted on the planning curve R, the stroke of each of the center bending jacks 13 is not changed, and the bent state between the adjacent units 11 is maintained as it is.

FIG. 5 is a plan sectional view for explaining a state between adjacent cylinders in the direction stabilizing device. Curve forming device 20
For example, as shown in FIG. 5, in the unit 25 on the rear side of the unit 25 trying to enter the planned curve R, each pressing jack 22 is driven to cause the ram 22a to protrude. The protruding ram 22a abuts against and presses against the pressure receiving wall 23 of the unit 25 which is about to enter the planned curve R. Here, the stroke of the pressing jack 22 on the inner peripheral side of the planned curve R is larger than the pressing jack 22 on the outer peripheral side of the planned curve R.
(For example, the inner peripheral side pressing jack 22 pulls the ram 22a completely back).
FIG. 5 shows the pressing jack 22 on the outer peripheral side.

Due to this difference in stroke, the unit 25 that is going to enter the planned curve R is bent relative to the rear unit 25 such that the outer peripheral side of the planned curve R is advanced forward from the inner peripheral side. , The posture is shifted along the planned curve R. Thus, each unit 2 of the curve forming device 20
5 is sequentially bent and propelled, and as a result, the excavating machine 10 and the entire curve forming device 20 are propelled along the planned curve R (see FIG. 8). Thereafter, since the curve shaping device 20 has completely shifted to the planned curve R, each pressing jack 2
2 does not change and the adjacent unit 25,
The bent state between 25 is maintained as it is. Excavating machine 10
Is also as described above.

Further, by adding and pushing the fume tube 50 from a starting shaft (not shown), the excavating device 1 is propelled forward as shown in FIG. The entire excavating machine 10 and the curve forming device 20 receive a propulsive force in the forward direction, and are propelled along the planned curve R. The perimeter mixing device 30 following the curve shaping device 20 is not so long in the propulsion direction, so that the excavating machine 10 already along the planned curve R
And smoothly transitions to the planned curve R following the curve forming device 20. Similarly, the flexible propulsion pipe 40 following the pipe circumference mixing device 30 also smoothly transitions to the planned curve R following the pipe circumference mixing device 30.

That is, in the flexible propulsion pipe 40, the cushion member 42 is deformed according to the bending angle between the concrete pipes 41, 41 in the planned curve R. The cushion material 42 is mainly compressed on the inner peripheral side of the planned curve R (either the left or right part in FIG. 4C), and subsequently the thinner part of the thickness W (the upper and lower parts in FIG. 4C). When the compression converges, the outer peripheral side of the planned curve R (either the left or right part in FIG. 4C) extends from that point as a starting point. As described above, when the movement of the thrust transmission position is completed (that is, the concrete pipe 41 is completely shifted on the planned curve R), the thrust transmission position is balanced and swells to the outer peripheral side of the planned curve R or the like. There is no such behavior. Since mainly the left and right portions of FIG. 4C where the thickness W is thickened are not compressed, stress concentration does not occur, and preferable transmission of thrust is guaranteed.

Further, as described above, since the flexible propulsion pipe 40 is appropriately bent and introduced into the excavation hole r excavated along the planned curve R (see FIG. 8), the fume pipe and the like are propelled at the curved portion. The installation work of a camber or the like, which has been performed at the time, is not required, and the complicated work is released.
In addition, it is possible to handle not only a curve in the horizontal direction (horizontal direction) but also a curve in the vertical direction. It should be noted that constructing an accurate curve is the basis of pipeline construction, and it is necessary to perform it as accurately as possible. However, it may inadvertently shift due to geological conditions and the like. In such a case, even if the curve of the drilling hole by the drilling machine 10 or the curve forming device 20 is incorrect,
The flexible propulsion tube 40 slides along the incorrectly curved hole, and does not generate excessive stress on the flexible propulsion tube 40 itself. This prevents the pipe from being damaged.

In the case of the cushion material insertion method (Sempra Curve System) described in "Prior Art", only the upper and lower portions of the cushion material are stuck, and the thickness of the cushion material is uniform. Initially, similarly to the flexible propulsion tube 40 of the present embodiment, the cushion material is compressed with the movement of the point of force, and the openings begin to open. However, even after the convergence of the compression, it opens further due to the lateral pressure from the outside ground. Therefore, the opening length of the aperture is affected by the lateral pressure, and there are inconveniences such as variation and change during excavation. On the other hand, the flexible propulsion pipe 40 employed in the present embodiment eliminates the above-described inconvenience as described above, and can appropriately transmit thrust to the excavating machine 10 and the like, which is advantageous in controlling the direction of the excavating machine 10. Becomes

In the state shown in FIG. 8, the fume tube 50 is further extended from the starting shaft (not shown) and pushed in, so that the excavating device 1 is propelled to the arrival shaft (not shown). Thereby, the excavating machine 10, the curve shaping device 20, and the pipe circumference mixing device 30 are collected in the arrival shaft and reused in the next construction. This is because the rear end of the tube mixing device 30 and the front end of the flexible propulsion tube 40 are detachable (that is, the curve propelling device 20 and the flexible propulsion tube 4
0 side is detachable). In particular, since the curve forming device 20 can be collected and reused, the equipment including the jack and the like can be effectively used without wasting, and low-cost construction is realized.

As described above, the flexible propulsion pipe 40
As shown in FIG. 9, the fume pipe 50 is laid from the arrival shaft (not shown) to the changing point P of the planned curve R, and the fume tube 50 is laid straight from the changing point P to the starting shaft (not shown). Was. The flexible propulsion pipe 40 and the fume pipe 50 are used as a sewer.

As described above, in the present embodiment, when excavation of the planned curve R is performed by the excavating machine 10, the curve forming apparatus 20 is bent in accordance with the curvature of the planned curve R. Is used as a guide to adjust the posture of the excavating machine 10 to the curvature of the planned curve R.
Articulated curve forming device 20 composed of a plurality of cylinders 21
Of the excavation hole r (FIG. 8) formed along the planned curve R, the curved shaping device 20 can closely adhere to the ground wall surface, the bearing area can be secured, and the curve forming device 20 suitably follows the curve R. I do. This is because the length L2 of the cylinder 21 is equal to the length L1 of the shell 12.
Due to being sufficiently shorter than. As described above, since the curve shaping device 20 is stably propelled along the planned curve R, the posture of the excavating machine 10 to which thrust is transmitted via the curve shaping device 20, that is, the excavation direction is stable, and the planned Inadvertent departure from the curve R is prevented. Therefore, the construction of a long-distance sharp curve as exemplified in the present embodiment can be performed accurately.

Further, since the entire length L3 of the curve forming device 20 is longer than the length L1 of the shell 12 at the head of the excavating machine 10, the wall contact area for obtaining the directional control reaction force on the shell 12 is reduced. It can be obtained in a direction stabilizing device, and an accurate excavation direction can be realized in curved construction.

Further, the pressure (oil pressure) acting on the plurality of pressing jacks 22 of the curve forming device 20 is measured at any time by the pressure measuring unit 60, and the measurement result is sequentially transmitted to the calculating unit 61. By the way, the calculation unit 61 includes a straight path or a planned curve R currently being propelled by the curve forming apparatus 20.
In the above, the predicted value of the pressure acting on each pressing jack 22 of the curve forming device 20 assuming that the propulsion is performed on an accurate route is calculated and stored in advance. And operation unit 6
Reference numeral 1 compares the predicted value with the transmitted measurement result and outputs the difference or the like as information on the digging state via a display means 62 such as a monitor.

For example, if the excavating machine 10
In the case where the vehicle travels further away, an excavation hole r having a curvature different from the original planned curve R is formed, and the subsequent curve forming device 20 is forcibly introduced into the excavation hole r. Since the bending state of the curve forming device 20 is adjusted to the curvature of the original planned curve R, each of the pressing jacks 22 of the curve forming device 20 is originally generated by the force received from the ground when introduced into the excavation hole r. Pressure that should not be applied acts (kneading phenomenon). The difference between the predicted value calculated by the calculation unit 61 and the measurement result indicates the pressure that should not be generated originally, and indicates the digging state that the digging direction of the digging machine 10 is shifted. . Therefore, by sequentially outputting such information on the excavation state, a deviation or the like from the planned curve R can be quickly detected, and a response such as correction of the excavation direction can be promptly taken before the deviation becomes large. It is. However, it is also possible to provide only a pressure gauge for each pressing jack 22, read the pressure measured by the pressure gauge, and judge the excavation state etc. based on the read pressure. It is possible. Note that the presence or absence of such a function of outputting information on the digging state is arbitrary in the configuration of the present invention, and therefore the present invention can be configured without having a function of outputting information on the digging state.

The collar 21b of the curve forming device 20
Is formed of a non-flexible member such as steel, the adjacent tubular bodies 21 and 21 are bent at the time of curving to form openings, so that the collar portion 21b jumps up to the outer peripheral side.
For this reason, earth and sand flows into the gap formed by the bouncing, and even if an attempt is made to eliminate the aperture during, for example, the construction of a straight line or a reverse curve, the aperture cannot be eliminated because the earth and sand are bitten. As a result, it may be inconvenient to form an accurate curve. Also, the color portion 21b
Is fitted with a rubber ring for waterproofing, but the above-mentioned splashing impairs the waterproofness function. However, when the collar portion 21b of the curve forming device 20 is formed of a flexible material such as rubber, the collar portion 21b follows the deformation of the cylinder connecting portion and jumps up even if the tube 21 is bent. Absent. And do not contact the ground. As a result, resistance during propulsion is less likely to occur, and smooth propulsion can be achieved even during curve construction. In addition, since jumping is eliminated, intrusion of earth and sand is prevented, and a water stopping effect is also ensured. In addition, the present structure has an advantage that it can be applied to a small-section tube because the connecting portion can be formed in a relatively small space.

As for the excavating machine 10, the water-stopping and bent structure are subjected to advanced processing from the viewpoint of repeated reuse. Although it is unavoidable that earth and sand are caught in the bent portion, the biting is released while repeating the bending operation of the strong middle bending jack 13. However, it is necessary to solve this problem in sharp curve construction. In the excavation machine 10 for sharp curve construction, the opening between the shells 12 and 12 is reduced by increasing the number of bends. However, due to the structure of the excavation machine 10, there is a limit in increasing the number of bends, and the cost increases. Leads to. Therefore, the number of bending portions of the excavating machine 10 will be about 3 to 4 at the maximum as in the present embodiment. As a basic countermeasure, the same thing as the above-described collar portion 21b (rubber cover) made of a flexible material of the curve forming device 20 is used for the excavating machine 1.
It is possible to form an accurate curve by installing between the shells 12, 12 which are the connecting portions of zero.

The pressing jack 2 of the curve forming device 20
2 were eight for each cylinder 21 (see FIG. 3). This makes it possible to select a jack arrangement at an optimum position for curve setting when rolling occurs. In addition, pressure oil generated by a hydraulic unit (not shown) is supplied in parallel from one switching valve to two pressing jacks 22 (a plurality of pressing jacks).
It is effective to ensure the synchronism of the reaction force generated in the two pressing jacks 22 (communication pipe hydraulic circuit).
As a specific example, as shown by a two-dot chain line in FIG.
Of the eight pressing jacks 22, hydraulic oil is movably circulated between the upper two pressing jacks 22, 22 and between the two lower pressing jacks 22, 22, between the pressing jacks 22, 22. The operating oil communication pipes 100 (operating oil distribution means) to be connected are connected respectively. Thereby, the pressing jacks 22, 22 connected by the hydraulic oil communication pipe 100
The stroke is automatically and appropriately adjusted according to the external force and the like by the free circulation of the hydraulic oil. In addition, a single jack requires a large jack capacity, but there is an advantage that a small capacity can be achieved by using a plurality of jacks. Further, since the jack reaction force points can be dispersed, there is an advantage that bearing stress concentration does not occur in the jack reaction force structural member. For example, the arrangement of four jacks is not efficient in generating a couple when forming a curve (opening). Since the eight jack arrangement can be arranged at the pipe end, there is a rationality in the opening couple. The presence or absence of such a hydraulic oil circulating means such as a communication pipe hydraulic circuit is optional in the configuration of the present invention, so the present invention can be configured without the hydraulic oil circulating means.

[Explanation of Machine Control Principle] The configuration, operation, effects, and the like of the excavating apparatus 1 including the curvilinear shaping apparatus 20 have been described in the above embodiment, but the curvilinear shaping apparatus (directional stabilizing apparatus) which is also a feature of the present invention. The supplementary explanation of the principle of machine control using is explained with a simple example.

FIG. 10 is a diagram schematically showing the relationship between the excavating machine 10 and the curve forming device 20. In FIG. 10, in order to make the example easy to understand, the excavation machine 10 of the type having no center break is employed. In the curve forming device 20, a plurality of units 25 are illustrated as an integral unit (actually, the units 25 include a plurality of units 25). Only the ram 22a of the pressing jack 22 at the foremost position is shown.
In a, the rear end of the excavating machine 10 is disposed so as to be able to be pressed.

As shown in FIG. 10, at the changing point P (curve start point), the thrust acting position of the curve forming device 20 is forcibly set outside the curve. For example, the tip of the ram 22a is brought into contact with an adjacent portion (pressure receiving wall 23) of the joint by extending the ram 22a of the pressing jack 22 in advance, and when the state of FIG. The ram 22a is shrunk only by the pressing jack 22 on the lower side of the drawing. A clearance is formed between the tip of the ram 22a of the pressing jack 22 inside the planned curve R and an adjacent part in the joint. At this time, the reaction force FC (earth pressure acting on the machine face plate) on the front surface of the excavating machine 10 acts on the machine axis CT, and the thrust FD from the curve shaping device 20 is applied to the ram 22a on the outer periphery of the curve.
Through the excavating machine 10. As a result, a couple MT that rotates the inside of the curve is generated in the excavating machine 10, and the excavating machine 10 easily (naturally) turns inside the curve and proceeds along the planned curve R.

FIG. 11 is a diagram showing a state change regarding the excavating machine 10 and the curve forming device 20. FIG. 11 schematically shows a relationship between a state change and a force in the excavation device 1. The state of FIG. 11A corresponds to the state of FIG. That is, at the changing point P, the thrust action position of the curve forming device 20 is forcibly set to the outside of the curve, the couple MT is generated in the excavating machine 10, and the direction of the excavating machine 10 is changed to the inside of the curve. In FIG. 11, the direction of the curve is opposite to that in FIG. 10; however, this is a difference in drawing convenience and does not indicate a technically different one. In the curve forming device 20, a plurality of units 25 are illustrated in roughly divided two parts. FIG. 11 shows an example of a type that does not include the pipe circumference mixing device 30, and the pressing jack 22 of the curvilinear shaping device 20, the cushion material 42 of the flexible propulsion pipe 40, and the like are not illustrated. Arrows in the figure indicate thrust or reaction force from the ground.

By further propelling, even if the excavating machine 10 enters the planned curve R as shown in FIG. 11B, the action position of the thrust FD in each unit 25 in the curve forming device 20 is forcibly set. By making the outside of the curve as shown in FIG.
Similarly to (a), a couple MT for rotating the preceding unit 25 to the inside of the curve is generated, and each unit 25 of the curve forming apparatus 20 easily (naturally) changes its direction to the inside of the curve to form the planned curve R. Follow along.

When the propulsion is further advanced and the excavation machine 10 to the flexible propulsion pipe 40 are completely within the planned curve R as shown in FIG. By maintaining a proper opening length (aperture between the units 25), the excavating machine 10 and the curve shaping device 20 become an integral rigid body having a clean curve. As a result, the direction of the curve can be stabilized, and the excavating machine 10 can continuously excavate a clean curve. Further, the flexible propulsion pipe 40 that follows is advantageous because the excavation hole has a clean curve, so that no extra lateral pressure acts.

When the curve forming device is not used as in the prior art, the direction of the machine tip side is forcibly changed by a direction correcting jack (center bending jack) of the excavating machine. However, in this case, the excavating machine was receiving a couple rotating outside the curve due to the reaction of the ground force acting on the machine axis and the thrust from the subsequent pipe. as a result,
The excavator received a reaction force from the side ground outside the planned curve and changed the direction of excavation, and could not form a clean curve as planned. However, in the above embodiment, the excavating machine 10
Can be easily (naturally) changed, and the excavating machine 10 can be stably propelled as a guide after entering the planned curve.

The excavating device based on the technical idea of the present invention is provided with at least a curving device. For example, the excavating machine is the excavating machine 1 described in the above embodiment.
0, the curve shaping apparatus 20, the pipe mixing apparatus 30, and the flexible propulsion pipe 40, a configuration without the pipe mixing apparatus 30 or a configuration without the pipe mixing apparatus 30 and the flexible propulsion pipe 40. Can be taken. Also, the excavating device can be configured only with a curve forming device without an excavating machine. In this case, a digging means such as a cutter is directly installed at the tip of the curve forming device.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a digging device according to the present invention.

FIG. 2 is a plan view (partially sectional view) of the curve forming device.

FIG. 3 is a view showing an arrangement state of a pressing jack in a cylindrical body.

FIG. 4 is a view showing a flexible propulsion tube.

FIG. 5 is a plan sectional view illustrating a state between adjacent cylinders in the curve forming device.

FIG. 6 is a schematic view showing a procedure of sharp curve construction.

FIG. 7 is a schematic diagram showing a procedure of sharp curve construction.

FIG. 8 is a schematic view showing a procedure of sharp curve construction.

FIG. 9 is a schematic view showing a procedure of sharp curve construction.

FIG. 10 is a diagram schematically showing a relationship between an excavating machine and a curve forming device.

FIG. 11 is a diagram showing a state change regarding the excavating machine and the curve forming device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 excavating device 10 excavating machine 12 shell 15 excavating means 20 direction stabilizing device (curve forming device) 21 cylindrical body 21 b color member (collar part) 22 jack means (pressing jack) 30 lubricating material injection means (pipe circumference mixing apparatus) 40 Flexible propulsion pipe 41 Concrete pipe 42 Flexible ring material (cushion material) 50 Fume pipe (propulsion pipe) 60 Pressure measurement unit 61 Information output unit (arithmetic unit) 62 Information output unit (display means)

 ──────────────────────────────────────────────────続 き Continuation of front page (71) Applicant 597024522 Sanko Consultant Co., Ltd. 1-8-9 Kameido, Koto-ku, Tokyo (71) Applicant 000157005 Kanden Kogyo Co., Ltd. 2-9-1 Honjohigashi, Kita-ku, Osaka-shi, Osaka No. 18 (72) Inventor Yoichi Sakuhara 6-4 F-term (reference) 2D054 AA02 AC18 AD02 AD28 AD33 BA17 GA04 GA06 GA17 GA23 GA34 GA38 GA44 GA63 GA97

Claims (10)

[Claims] An excavating machine having one or more shells arranged in series in the propulsion direction, and excavation means provided in the shell at the head of the propulsion direction and capable of excavating the ground in front, and a concrete pipe. And a flexible propulsion pipe, which is formed by alternately connecting the propulsion direction and the flexible ring material in series in the propulsion direction, and a flexible propulsion pipe arranged behind the excavation machine. The direction stabilizing device comprises a plurality of cylinders having a length in the propulsion direction shorter or equal to the length of the shell body, which are arranged in series in the propulsion direction, and the cylinders adjacent to the propulsion direction. A plurality of jack means are provided between the cylinders so as to be able to be pushed open by the jack means, and the plurality of jack means between the adjacent cylinders in the propulsion direction are arranged along the peripheral surface of the cylinder. And behind the directional stabilizer Excavation apparatus characterized by being configured to connect detachably the flexible propulsion tube. 2. The excavating device according to claim 1, wherein a length of the direction stabilizing device in the propulsion direction is longer than a first shell in the propulsion direction. 3. An information output unit for outputting information on a digging state based on a measurement result of the pressure measuring unit, wherein the jack means is a hydraulic jack, a pressure measuring unit for measuring a pressure acting on the hydraulic jack is provided. The excavating device according to claim 1, further comprising: 4. A tubular collar member is provided between said tubular bodies adjacent to each other in the propulsion direction so as to cover a gap between these tubular bodies, and said collar member is formed of a flexible material. The digging device according to claim 1. 5. The hydraulic device according to claim 5, wherein said jack means is a hydraulic jack, and hydraulic oil circulating means for movably circulating hydraulic oil between two or more jack means among said plurality of jack means. The digging device according to claim 1, wherein the digging device is connected. 6. The excavation machine excavates the ground in front of the propulsion direction by sequentially adding and pushing a propulsion pipe from the back of the excavation machine, and laying the propulsion pipe subsequent to the excavation machine on the ground. In the propulsion method, a bendable cylindrical direction stabilizer having a plurality of joints in a propulsion direction is connected between the excavating machine and the propulsion pipe, and the excavating machine performs curve excavation. In this case, the directional stabilizer is bent in accordance with the curvature of the curve to be excavated, so that the orientation of the excavating machine is adjusted to the curvature using the directional stabilizer as a guide. Construction method. 7. A flexible propulsion pipe formed by alternately connecting a concrete pipe and a flexible ring material in series in the propulsion direction is connected to the rear of the direction stabilizing device, and the excavation machine performs curve excavation. When performing, the flexible propulsion pipe is bent and introduced into the already drilled drilled hole, and the posture of the flexible propulsion pipe is held in accordance with the drilled hole, so as to match the curvature of the curve to be drilled. 7. The propulsion method according to claim 6, wherein the excavating machine, the direction stabilizing device, and the flexible propulsion pipe, which are held in a posture, stabilize an excavating direction by the excavating machine. 8. A propulsion method for propelling and laying the propulsion pipe on the ground by sequentially adding and pushing a propulsion pipe from the rear thereof while excavating the ground in the front of the propulsion direction by the excavation means, Between the propulsion pipe, a cylindrical direction stabilizing device in which a plurality of joints are arranged in the propulsion direction is installed, and when performing a curve excavation by the excavation means, at an outer peripheral side position of a curve to be excavated. A thrust transmitted at an outer peripheral position of a curve to be excavated by connecting the joint to be capable of transmitting a thrust and by setting the joint to be contractible at an inner peripheral position of the curve to be excavated; And a reaction force received from the ground to generate a couple, and the couple causes the excavating direction of the excavating means to be changed in accordance with the curvature of the curve to be excavated. 9. The joint is provided with jack means capable of driving a ram in a propulsion direction at an outer peripheral position and an inner peripheral position of the curve to be excavated, respectively. When carrying out, the ram of the jack means is protruded at the outer peripheral position of the curve to be excavated to connect the joint so that thrust can be transmitted, and the ram of the jack means is provided at the inner peripheral position of the curve to be excavated. The propulsion method according to claim 8, wherein the joint is retractable by retracting the joint. 10. When excavating a curve by the excavating means, the tip of the ram of the jack means is brought into contact with an adjacent part of the joint at an outer peripheral position of the curve to be excavated, and The propulsion method according to claim 9, wherein a clearance is formed between an end of the ram of the jack means and an adjacent part of the joint at an inner peripheral position.