JP2018172929A - Blade edge propulsion method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blade edge propulsion method capable of efficiently performing the digging operation of hollow pipe members while allowing earth-retaining of natural ground of the cutting face to be stably held when the digging operation of the hollow pipe members are stopped.SOLUTION: In a blade edge propulsion method according to the present invention including steps of pushing hollow pipe members forward by a propulsive force of a propulsive jack 22 while cutting a cutting face by a digging blade edge member 13 of each tip portion of hollow pipe members 11 and setting the hollow pipe members in the earth, during a stop of the digging operation of the hollow pipe members 11, an air bag member 12 is attached on the digging blade edge member 13 of each hollow pipe member 11 of the state of stopping the digging operation, and by means of expanding the attached air bag member 12, a tip end surface portion 12a of the expanded air bag member 12 is pushed upon the cutting face 30 to be brought into close contact, and a side peripheral surface portion 12b of the expanded air bag member 12 is pushed upon the inner peripheral surface of the digging blade edge member 13 to obtain a support reaction force, thereby forming an earth-retaining on the cutting face 30.SELECTED DRAWING: Figure 1

Description

  TECHNICAL FIELD The present invention relates to a blade edge propulsion method, and in particular, hollow pipe members arranged in a plurality of rows in the circumferential direction are each excavated while cutting a face surface with an excavation blade edge member and installed in the ground. It relates to the blade edge propulsion method.

  For example, an R & C method (see, for example, Patent Document 1) and an SFT method (see, for example, Patent Document 2) are known as methods for constructing an underground passage that crosses an existing railway or road below the ground. In these methods, the hollow pipe members made of steel, preferably arranged in a plurality of rows in the circumferential direction, are propelled installed at the rear while cutting the face surface with a digging blade member attached to the tip. It is installed in the ground by the so-called blade-protrusion method, in which each is dug into the ground by the propulsive force from the jack. In the construction in which the hollow pipe members arranged in a plurality of rows are each installed in the ground by the blade propulsion method, each hollow pipe member continuously connects a plurality of unit pipe members integrally in the excavation direction. In the starting base, the unit pipe member that is continuously connected with the unit pipe member that has been added is integrated while the next unit pipe member is sequentially added to the rear end portion of the unit pipe member that is continuously provided. The hollow pipe member is made to dig into the ground by being pushed into the ground with a propulsion jack.

  Then, in the construction where the hollow pipe members arranged in multiple rows are installed in the ground by the blade propulsion method, the hollow pipe members propel the hollow pipe members of each row while adding the unit pipe members. Although it digs into the ground individually by jacks, it may be necessary to suspend the excavation work of each hollow pipe member, for example, at night. In addition, among the hollow pipe members arranged in a plurality of rows, after the hollow pipe members in a predetermined row are dug in advance, the dug work of the preceding hollow pipe members is temporarily stopped, and the hollow rows in other rows are temporarily stopped. After waiting for the pipe member to dig up and catch up, the hollow pipe member of the predetermined row that has been paused is resumed to resume the hollow pipe member of a plurality of rows in an efficient and stable state. There is a case where a construction method is adopted that enables installation in the ground side by side.

  As described above, when the hollow pipe member is temporarily suspended during the digging operation, the face surface is in a released state at the distal end opening of the excavation blade member attached to the distal end of the hollow pipe member. As a conventional method for retaining the ground surface of the working face, for example, a length slightly longer than the opening width of the tip opening portion of the excavation blade member is required. By inserting both ends of the wooden sheet pile for earth retaining into the ground on both sides of the tip opening on the face, and engaging with the opening edge of the tip of the excavation blade member, the ground of the face A method has been adopted in which wooden sheet piles are attached to a plurality of levels so as to support the earth pressure from the ground surface of the facet by the plurality of attached wooden sheet piles.

JP 2010-222882 A JP 2012-144492 A

  However, when the excavation work is suspended, the conventional method of earthing the ground surface of the face with a wooden sheet pile allows the attached multi-stage wooden sheet pile to be in close contact with the ground face of the face surface. It is difficult, and it is easy to loosen the ground of the face, and insert the both ends of the wooden sheet piles of multiple stages into the ground of the face and engage each with the opening edge at the tip of the excavation blade member. When the excavation work is resumed, it takes a lot of work to remove these multi-stage wooden sheet piles.

  Further, in the blade edge propulsion method, a lubricant or the like is used to improve the slip and smoothly dig the hollow pipe member by the propulsion jack on the ground of the outer peripheral portion of the excavation blade member or the hollow pipe member. While the excavation work is suspended, the filler may be injected from the inside of the excavation blade member or hollow pipe member, but in the conventional method of earthing the ground surface of the face with a wooden sheet pile In particular, when injecting the filler into the ground of the outer peripheral portion of the excavation blade member, the injected filler wraps around the tip opening of the excavation blade member, and the wooden sheet pile and face face attached in multiple stages It leaks into the mine of the excavation blade member from the gap between the natural ground and the gap between the adjacent wooden sheet piles, which affects the working environment in the mine and easily wastes the filler.

  The present invention makes it possible to make the earth retaining member adhere to the ground surface of the face face easily when the excavation work of the hollow pipe member is stopped, so that the ground face of the face surface is stable in a stable state. In addition to being able to fasten, reduce the labor when installing and removing the earth retaining member, and efficiently carry out the excavation work of the hollow pipe members arranged in multiple rows in the circumferential direction The purpose is to provide a cutting edge propulsion method that can be used.

  According to the present invention, the hollow pipe members arranged in a plurality of rows in the circumferential direction are each cut by a driving force from a propulsion jack installed on the rear side while cutting the face by a digging blade member attached to the tip. It is a blade edge propulsion method that digs up and installs in the ground, wherein the hollow pipe member is formed by connecting a plurality of unit pipe members integrally in the digging direction, While the excavation work of the hollow pipe member is paused, an airbag member is set on the excavation blade member of the hollow pipe member that has paused the excavation work, and the set airbag member is inflated to expand the hollow pipe member. The front end surface portion of the airbag member pressed against the face surface and brought into close contact, and the side peripheral surface of the expanded airbag member is pressed against the inner peripheral surface of the excavation blade member to obtain a support reaction force It, by providing a cutting edge jacking method for earth retaining the working face surface is obtained by achieving the above object.

  The blade edge propulsion method according to the present invention is configured such that the excavation blade edge and the hollow pipe member are disposed on the outer peripheral portion of the excavation blade edge while retaining the face by expanding the airbag member. It is preferable to inject the filler from the inside of the member or the hollow pipe member.

  Moreover, it is preferable that the blade edge propulsion method of the present invention shrinks and removes the inflated airbag member when resuming the excavation work by the hollow pipe member that has been suspended.

  Further, in the blade edge propulsion method of the present invention, the airbag member is provided with a transparent viewing window portion, and the face surface in front of the hollow pipe member during which the excavation work is suspended through the viewing window portion. It is preferable to observe this situation.

  Furthermore, in the blade edge propulsion method of the present invention, it is preferable that the hollow pipe member has a substantially square or rectangular box-shaped hollow cross-sectional shape.

  According to the blade edge propulsion method of the present invention, when the excavation work of the hollow pipe member is suspended, the earth retaining member can be easily adhered to the ground surface of the face surface as a whole, The pile can be secured in a stable state, and the labor for installing and removing the retaining member can be reduced, and the hollow pipe member arranged in multiple rows in the circumferential direction can be dug. , Can go efficiently.

In the blade edge propulsion method according to a preferred embodiment of the present invention, it is a schematic cross-sectional view for explaining a state in which a face surface at the tip of a hollow pipe member is earthed by an airbag member. It is the simplified rear view which looked at FIG. 1 from the back explaining the structure of an airbag member. The valve unit connected to the airbag member will be described. (A) is a schematic diagram, (b) is a schematic diagram in a state where air is being fed, and (c) is a schematic diagram in a state where air is being extracted. It is. (A)-(e) is explanatory drawing of the R & C method by which each hollow pipe member is dug by the blade edge | tip propulsion method which concerns on preferable one Embodiment of this invention.

  The blade edge propulsion method according to a preferred embodiment of the present invention is an underpass by the box structure 20 across the ground below the rail 27 of the railway, for example, by the R & C method shown in FIGS. A plurality of rows of hollow pipe members that form a pipe row 21 arranged to have a U-shaped cross-sectional shape, which is replaced with the box structure 20 in advance of the box structure 20. 11 was adopted as a construction method for installing each in the ground. Here, as described in, for example, Japanese Patent Application Laid-Open No. 2010-222882, the R & C method is preferably a substantially rectangular (including substantially square) hollow cross section along the outer peripheral shape of the box structure 20 to be installed. A plurality of hollow pipe members 11 composed of box-shaped roof pipes having a shape are installed in advance to form a pipe row 21 arranged in a U-shaped cross-sectional shape composed of an upper wall portion and a pair of side wall portions on both sides ( 4 (a) and 4 (b)), after that, the end face of the ready-made box structure 20 is brought into contact with the rear end face of the pipe row 21 having a U-shaped cross section via the intermediate push jack 24a ( 4 (c)), by moving the box structure 20 forward by the main push jack 24b (see FIG. 4 (d)), the box structure 20 is made up of a plurality of hollow pipe members (box roof pipes). 11 and a U-shaped pipe row 21 Instead it came, a known method which slide into installed in the ground (see FIG. 4 (e)).

  The blade edge propulsion method of the present embodiment is used for excavating a plurality of hollow pipe members 11 forming a U-shaped pipe row 21 on the ground below the railroad rail 27. The ground of the face of the tip of one or two or more hollow pipe members 11 that are once suspended can be easily and quickly earthed, and the excavation work can be resumed quickly from the earthed state. In this way, the plurality of hollow pipe members 11 can be arranged in one piece and installed in the ground in a stable state and efficiently.

  That is, in the R & C method, it may be necessary to pause the excavation work of each hollow pipe member 11 at night, for example, and one or more of the hollow pipe members 11 arranged in a plurality of rows are arranged. After the predetermined hollow pipe member 11 has been dug in advance, the dug operation of the preceding hollow pipe member 11 is temporarily stopped, and after waiting for another hollow pipe member 11 to be dug and caught up, The excavation work of the predetermined hollow pipe member 11 that has been performed may be resumed, but according to the blade edge propulsion method of the present embodiment, the excavation work of one or more hollow pipe members was suspended in this way. At this time, the ground of the face of the tip of the hollow pipe member 11 where the excavation work is stopped is quickly settled in a stable state, and the excavation work is resumed promptly, so that a plurality of hollow pipes By installing the timber 11 into the ground, thereby making it possible to efficiently form a pipe column 21 of U-shaped cross section.

  In the blade edge propulsion method according to the present embodiment, the hollow pipe members 11 arranged in a plurality of rows in the circumferential direction are installed rearward while cutting the face surface with the excavation blade member 13 attached to the tip. The hollow pipe member 11 includes a plurality of unit pipe members 11a in the direction of digging, each of which is dug by the propulsive force from the propulsion jack 22 (see FIG. 4A) and installed in the ground. 1. As shown in FIG. 1, the excavation of the hollow pipe member 11 that has stopped the excavation operation is performed while the excavation operation of the hollow pipe member 11 is suspended. When the airbag member 12 is set on the blade member 13 and the set airbag member 12 is inflated, the front end surface portion 12a of the inflated airbag member 12 is pressed against the face surface 30 and brought into close contact therewith. To, by obtaining the supporting reaction force against the inner peripheral surface of the side peripheral surface portion 12b of the air bag member 12 inflated digging edge port member 13, the cutting face surface 30 is adapted to earth retaining.

  Further, in the blade edge propulsion method according to the present embodiment, the excavation blade is provided on the outer peripheral portion of the excavation blade member 13 and the hollow pipe member 11 while the face 30 is retained by expanding the airbag member 12. The filler is injected from the inside of the mouth member 13 and the hollow pipe member 11.

  Furthermore, in the blade edge propulsion method of the present embodiment, when the excavation work by the hollow pipe member 11 that has been suspended is resumed, the expanded airbag member 12 is contracted and removed.

  In this embodiment, the box-shaped roof pipe 11 which is a well-known rectangular pipe used for a R & C construction method can be used as the hollow pipe member 11 which forms the pipe row | line | column 21 dug by the blade edge | blade propulsion construction method. The box-shaped roof tube 11 has a substantially rectangular (substantially square) cross-sectional shape of, for example, about 800 mm in length and width, and has a hollow portion in which an operator can enter and work.

  The box-shaped roof pipe 11 is composed of a plurality of unit pipe members 11a connected by being connected in the digging direction (axial direction) X (see FIG. 4A), and the box-shaped roof pipe 11 is the starting base. Along with the excavation from 23 to the arrival base 25, the plurality of unit pipe members 11a have, for example, bolt fastening holes 26a attached to the four corner portions at both axial ends of the unit pipe member 11a. By being connected by the bolt member via the connecting rib 26 (see FIG. 1), the members are sequentially added from the rear. Furthermore, the box-shaped roof tube 11 is preferably provided with engagement pieces (not shown) that protrude outward from the side surface and extend in the axial direction, and these engagement pieces are engaged with each other. By forming a joint portion between the adjacent box-shaped roof pipes 11 and using this as a guide, it is possible to avoid displacement during excavation.

  Furthermore, in the present embodiment, a friction cutter plate (not shown) is attached to a portion of each unit pipe member 11a that becomes the outer peripheral surface of the pipe row 21 arranged to have a U-shaped cross-sectional shape. ing. When adding a plurality of unit pipe members 11a, these friction cutter plates are joined together by welding or the like, and are continuously integrated in the excavation direction X, so that a plurality of rows of hollow pipe members 11 installed in the ground In each case, a friction cutter plate that is continuous in the digging direction X is attached to a portion that is an outer peripheral surface of the pipe row 21. By attaching a friction cutter plate to the outer peripheral surface of the pipe row 21 formed by the plurality of hollow pipe members 11, the box structure 20 is advanced by moving the box structure 20 forward. When installing in the ground (see FIG. 4 (d)), the pipe rows 21 and the outer peripheral surface of the box-shaped underground structure 20 are cut off from the surrounding ground by the friction cutter plate. And the box underground structure 20 can be pushed out smoothly.

  And in this embodiment, the excavation operation | work of each box-shaped roof pipe | tube 11 was attached to the front-end | tip part of the box-shaped roof pipe | tube 11 by the operation | work by the worker who entered the pit inside the box-shaped roof pipe | tube 11, for example. Excavation ground 30 exposed at the tip opening of excavation blade member 13 is excavated to remove excavated earth and sand and propulsion jack 22 provided at start base 23 in the rear of excavation direction X. The box-shaped roof pipe 11 is pushed out in the digging direction X by the propulsive force from the side, and digging toward the arrival base 25. In the present embodiment, for example, when the work is at night, it may be necessary to temporarily stop the excavation work of the box-shaped roof pipe 11 before the box-shaped roof pipe 11 reaches the arrival base 25. While the excavation work of the hollow pipe member 11 is suspended, the face 30 exposed at the tip opening of the excavation blade member 13 is easily and stably caused by the inflated airbag member 12. It is designed to be temporarily fixed.

  That is, in the blade edge propulsion method of the present embodiment, as shown in FIG. 1, the airbag member 12 is set on the excavation blade edge member 13 of the hollow pipe member 11 that has stopped the excavation work, and the set airbag member 12 is By inflating, the front end surface portion 12a of the inflated airbag member 12 is pressed against the face surface 30 and brought into close contact with the side surface portion 12b of the inflated airbag member 12 on the inner peripheral surface of the excavation blade member 13. The face surface 30 is earthed by pressing and obtaining a support reaction force.

  Here, the airbag member 12 used in the blade edge propulsion method of the present embodiment is, for example, a sheet material made of tarpaulin, which is known as a material used for a flexible container. The front end surface portion 12a that matches the shape of the exposed face 30 can be easily manufactured so as to have a shape that is provided at the time of expansion. Further, the airbag member 12 includes a front end surface portion 12a that inclines along the shape of the face surface 30 when inflated, and a side peripheral surface portion having a shape along the inner peripheral surface of the digging blade member 13 having a substantially rectangular cross-sectional shape. 12b is formed so as to have a substantially hexahedral shape.

  Further, as shown in FIG. 2, the back surface portion 12c of the air bag member 12 on the side opposite to the front end surface portion 12a is supplied with air to the air bag member 12 to be inflated, or air is extracted to be contracted. A valve unit 15 is connected via an air inlet member 12d, and a hose for holding the third flow path 15c of the valve unit 15 in the vicinity of the back surface portion 12c. A fixed band 12e is attached. The air bag member 12 is in a state where each surface of a substantially hexahedron shape is color-coded in order to facilitate the work when being set on the excavation blade member 13. For example, the tip surface portion 12a is transparent, the back surface portion 12c is red, the upper surface side peripheral surface portion 12b is blue, and the other side peripheral surface portions 12b are normal colors. Furthermore, the back surface portion 12c of the airbag member 12 is provided with a transparent viewing window portion 12f, and the face surface at the tip of the hollow pipe member 11 during which the excavation work is suspended through the viewing window portion 12f. 30 situations can be observed.

  In this embodiment, when stopping the excavation work of the hollow pipe member 11, the airbag member 12 is set on the excavation blade member 13 at the tip, and air is supplied from the compressor (not shown) via the valve unit 15. By supplying, the set airbag member 12 is inflated. Here, as shown in FIG. 3A, the valve unit 15 includes a first flow path 15a and a second flow path 15b that can be connected to the compressor, and a third flow path 15c that is connected to the airbag member 12. And a fourth flow path 15d branched from the second flow path 15b, a regulator 15e for adjusting the pressure of air flowing in from the compressor, and a vacuum generator 15f for applying a negative pressure to the airbag member 12. Has been.

  The first flow path 15a and the second flow path 15b are detachably connected to an air hose (not shown) extending from the compressor. The first flow path 15a and the second flow path 15b are connected to the third flow path 15c via the switching valve 15g, and the first flow path 15a and the third flow path 15c are operated by operating the switching valve 15g. And the second flow path 15b and the third flow path 15c can be communicated (see FIG. 3C). The third flow path 15c is detachably connected to the airbag member 12 via the air inlet member 12d. The fourth flow path 15d is branched from between the second flow path 15b and the switching valve 15g.

  The regulator 15e is attached to the first flow path 15a, and can adjust the pressure of the compressed air flowing into the airbag member 12 via the first flow path 15a. In the present embodiment, the regulator 15e functions as a safety device that prevents the pressure inside the inflated airbag member 12 from exceeding a preset pressure of, for example, 100 to 200 kPa (1 to 2 atmospheres). The inside of the back member 12 can be depressurized.

  The vacuum generator 15f is attached to the fourth flow path 15d branched from the second flow path 15b, and as shown in FIG. 3C, the compressed air that flows in from the compressor via the second flow path 15b. By narrowing down and exhausting the throttled air at a high speed, a negative pressure can be applied to the airbag member 12 connected via the switching valve 15g. Thus, as will be described later, when the expanded airbag member 12 is contracted and removed, the air is smoothly extracted from the expanded airbag member 12 when the excavation work of the hollow pipe member 11 is resumed. Thus, the airbag member 12 can be easily contracted.

  In the present embodiment, when the airbag member 12 is set in the excavation blade member 13 of the hollow pipe member 11 that has stopped the excavation work, the first flow path 15a and the first flow path 15a are changed by operating the switching valve 15g of the valve unit 15. The three flow paths 15c are communicated (see FIG. 3B), and the compressed air supplied from the compressor is sent into the airbag member 12. The airbag member 12 into which the compressed air is sent is gradually inflated. For example, after about 1 minute from the start of air introduction, the airbag member 12 expands into a three-dimensional shape with an internal pressure of 10 kPa, for example.

  As a result, as shown in FIG. 1, the airbag member 12 presses the four side peripheral surface portions 12b against the inner peripheral surface of the excavating blade member 13 having a substantially rectangular cross-sectional shape, thereby providing a sufficient support reaction force. In addition, the tip surface portion 12a can be easily and firmly adhered as a whole in a state in which the tip surface portion 12a is adapted to the shape of the ground surface of the face surface 30 due to its flexibility. In addition, by using the expanded airbag member 12 as a retaining member, the ground surface of the face 30 of the hollow pipe member 11 that has stopped the excavation work in a state that can withstand an earth pressure load equivalent to 0.03 MPa, for example. Can be held in a stable state. Compared to conventional earth retaining members made of wooden sheet piles, the earth retaining member made of the air bag member 12 has higher adhesion to the ground surface of the face surface 30 and effectively relaxes looseness of the ground surface of the face surface 30. It becomes possible to do.

  In the present embodiment, the excavation blade member 13 or the hollow pipe member 11 has an excavation blade member on the ground of the outer periphery of the excavation blade member 13 while retaining the face 30 by expanding the airbag member 12. 13 and the hollow pipe member 11 are preferably filled with a filler such as a lubricant to improve slipping and facilitate the hollow pipe member 11 to be digged by the propulsion jack 22. While holding the face 30 with the air bag member 12, the filler is injected into the ground of the outer peripheral portion of the hollow pipe member 11, so that the injection is performed as in the conventional method of holding down with the wooden sheet pile. The filled filler wraps around the opening at the tip of the excavation blade member 13, and from the gap between the wooden sheet pile and the ground surface of the face and the gap between adjacent wooden sheet piles, the inside of the excavation blade member 13 It is possible to effectively avoid leakage to the working environment in the mine and the possibility of waste of the filler.

  Furthermore, in this embodiment, the excavation work by the hollow pipe member 11 that has been suspended can be resumed by shrinking and removing the airbag member 12 that has been inflated. In order to contract the airbag member 12 that has been inflated, the second flow path 15b and the third flow path 15c are communicated by operating the switching valve 15g of the valve unit 15 described above (FIG. 3C). Reference), an air bag connected to the third flow path 15c by discharging the air flowing in from the compressor via the second flow path 15b at a high speed from the fourth flow path 15d via the vacuum generator 15f. By applying a negative pressure to the member 12 to smoothly extract air from the airbag member 12, the airbag member 12 can be easily contracted. That is, in the present embodiment, a lot of labor is required by a simple operation of inflating or contracting the airbag member 12 set on the excavation blade member 13 of the hollow pipe member 11 that has stopped the excavation operation. Therefore, the excavation work can be resumed smoothly by earthing the ground of the hollow pipe member 11 where the excavation work has been stopped smoothly or by removing the earth retaining member that has been earthed.

  By these, according to the blade edge propulsion method of the present embodiment, when the excavation work of the hollow pipe member 11 is stopped, the airbag member 12 inflated to the ground of the face 30 is easily adhered as a whole. This makes it possible to temporarily hold the ground of the face 30 in a stable state, and to reduce the trouble of installing and removing the earth retaining member by the airbag member 12. Thus, the excavation work of the hollow pipe members 11 arranged in a plurality of rows in the circumferential direction can be performed efficiently.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the hollow pipe members arranged in a plurality of rows in the circumferential direction are not necessarily provided with a substantially square or substantially rectangular box-shaped hollow cross-sectional shape, and may have a circular hollow cross-sectional shape or the like. . The hollow pipe members arranged in a plurality of rows in the circumferential direction do not necessarily have to form pipe rows arranged in a U-shaped cross-sectional shape, and are arranged in other shapes such as a circular ring or a rectangular ring. A pipe row may be formed.

11 Hollow pipe member (box-type roof pipe)
11a Unit pipe member 12 Air bag member 12a Front end surface portion 12b Side peripheral surface portion 12c Back surface portion 12d Air inlet member 12e Hose fixing band 12f Viewing window portion 13 Excavation edge member 15 Valve unit 15a First flow path 15b Second flow path 15c 3rd flow path 15d 4th flow path 15e Regulator 15f Vacuum generator 15g Switching valve 20 Box structure 21 Pipe row 22 Propulsion jack 23 Starting base 24a Middle push jack 24b Main push jack 25 Reaching base 26 Connecting rib 26a Bolt fastening hole 27 Railroad rail 30 Face face X Digging direction

Claims (5)

The hollow pipe members arranged in a plurality of rows in the circumferential direction are each excavated by the propulsive force from the propulsion jack installed at the rear, while cutting the face by the excavation blade member attached to the tip part, A blade edge propulsion method installed in the ground,
The hollow pipe member is formed by connecting a plurality of unit pipe members integrally in the digging direction,
While the excavation work of the hollow pipe member is paused, an airbag member is set on the excavation blade member of the hollow pipe member that has paused the excavation work, and the set airbag member is inflated to expand the hollow pipe member. By pressing the front end surface portion of the airbag member against the face surface and bringing it into close contact, the side surface portion of the inflated airbag member is pressed against the inner peripheral surface of the excavation blade member to obtain a support reaction force. Blade edge propulsion method for retaining earth.   While the face surface is earthed by inflating the airbag member, a filler is provided on the outer peripheral portion of the excavation blade member or the hollow pipe member from the inside of the excavation blade member or the hollow pipe member. The blade edge propulsion method according to claim 1, wherein a slag is injected.   The blade edge propulsion method according to claim 1 or 2, wherein when the excavation work by the hollow pipe member that has been stopped is resumed, the inflated airbag member is contracted and removed.   The air bag member is provided with a transparent inspection window portion, and the state of the face surface in front of the hollow pipe member during which excavation work is suspended is observed through the inspection window portion. The blade edge propulsion method according to any one of the above.   The blade edge propulsion method according to any one of claims 1 to 4, wherein the hollow pipe member has a substantially square or substantially rectangular box-shaped hollow cross-sectional shape.

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