JP2020007819A - Cutter board, shield machine with the same, and tunnel excavation method using shield machine - Google Patents

Abstract

To change a direction of a shield machine smoothly in curved surface construction.SOLUTION: A cutter board 2 rotatably provided on a front of a machine body comprises a plurality of cutter bits 22a, 30, 30a arranged on a front surface of the cutter board 2 for excavating a face in the traveling direction, and a copy cutter 31a arranged to be extendable and contractable from a side surface of the cutter board 2 for performing extra excavation in the curved surface construction of a tunnel. The copy cutter 31a extends obliquely forward from the side surface of the cutter board 2. The amount of protrusion from the front surface of the cutter board 2 at the time of maximum extension is equal to or greater than the installation height of the outermost scraper tooth 30a which is disposed on the outer circumference of the cutter board 2 and has the lowest installation height.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a cutter machine, a shield machine having the same, and a tunnel excavation method using the shield machine, and more particularly, to a copy cutter provided on the cutter machine and used for curved construction of the shield machine.

  The shield excavator used in the shield construction method to build a tunnel in the ground excavates the ground by rotating the cutter plate pressed against the face while stabilizing the face, while the inner periphery of the excavated pit Build a tunnel by assembling segments into the tunnel.

  Here, when constructing the tunnel, curved construction is performed as needed. In the curved construction, a copy cutter provided on a side surface of the cutter board is used.

  The copy cutter is built into the side of the cutter board provided at the front of the shield machine, and is a cutter that expands and contracts according to the amount of extra digging required. It is stored on the side of the cutter board, and when digging a curved part, it excavates while expanding and contracting from the side of the cutter board.

  Specifically, when excavating the inner part of the tunnel curve, the face protruding from the side of the cutter board is excavated (excavation) larger than the cutter face, and when excavating the outer part of the tunnel curve, the face inside the cutter board is excavated. And excavates along the cutter board. As a result, there is no earth and sand in the portion where the excavation has been performed, and it is possible to bend without resistance when trying to change the traveling direction of the shield excavator by the half-bent jack.

  In addition, as a technique relating to a copy cutter of a cutter board, those described in Patent Literature 1 (JP-A-2013-231318) and Patent Literature 2 (JP-A-2008-240460) are known.

JP 2013-231318 A JP 2008-240460 A

  Here, the copy cutter has a structure protruding vertically from the side surface of the cutter board. As shown in FIG. 8, when the dugout is performed by such a copy cutter 131, in the region R <b> 2 from the front surface of the cutter board 120 to the dugout portion, that is, with respect to the direction in which the shield excavator 100 changes its direction, Sediment remains. Then, the remaining soil is pressed by the side surface of the cutter board 120, but the reaction force of the remaining soil is applied to the cutter board 120 without being easily compressed, so that the direction change of the shield machine 100 is hindered.

  Further, since the copy cutter 131 projects vertically from the side surface of the cutter board 120, the projecting position is slightly behind the front face of the cutter board 120. Therefore, if the copy cutter 131 is made to protrude at the position where the curve starts to bend, the start position of the overdig is delayed. As a result, the rear end of the shield machine 100 comes into contact with the inner surface of the curved portion, and it is difficult to change the direction. Therefore, in order to avoid such a situation, the copy cutter 131 is protruded before the curve starts to be dug unnecessarily to prevent the rear end of the shield machine 100 from coming into contact with the earth and sand. Was. Then, the excavated earth and sand discharged increases, and the filler injected into the outside of the shield machine 100 increases accordingly.

  The present invention has been made in view of the technical background described above, and has a cutter board capable of smoothly changing the direction of a shield machine in curved construction, a shield machine equipped with the cutter machine, and tunnel excavation using the shield machine. The aim is to provide a method.

  In order to solve the above-mentioned problem, a cutter board according to the present invention according to claim 1 is a cutter board installed in a shield machine for excavating a ground and constructing a tunnel, and a plurality of cutter boards are provided on a front surface of the cutter board. A cutter bit that is arranged and excavates a face in the traveling direction, and a copy cutter that is arranged to be able to expand and contract from the side surface of the cutter board and performs extra excavation in the curved surface construction of the tunnel, wherein the copy cutter is provided with a cutter of the cutter board. Extending obliquely forward from the side, the amount of protrusion from the front surface of the cutter board at the time of maximum extension is equal to or greater than the installation height of the lowest installation height of the cutter bit arranged on the outer periphery of the cutter board, It is characterized by the following.

  According to a second aspect of the present invention, in the invention according to the first aspect, an amount of extension of the copy cutter from a side surface of the cutter board is set to be equal to or more than a necessary extra digging amount when designing the cutter board. The installation angle of the copy cutter is set such that when the copy cutter is extended to the installation height of the cutter bit disposed on the front surface of the cutter board, the leading end reaches the amount of extension from the side surface. It is characterized by that.

  According to a third aspect of the present invention, there is provided a shield machine in which the cutter panel according to the first or second aspect is rotatably provided on a front surface of an apparatus body. .

  According to a fourth aspect of the present invention, there is provided a tunnel excavation method using a shield excavator for excavating ground and constructing a tunnel, the method comprising: The copy cutter arranged on the side of the cutter board installed in the excavator, the projecting amount from the front surface of the cutter board is equal to or greater than the installation height of the lowest installation height of the cutter bit arranged on the outer periphery of the cutter board. It is arranged so as to be able to expand and contract diagonally forward of the cutter board so that the dug in the curve construction of the tunnel is performed using the copy cutter, and a space necessary for the shield machine to bend is formed. , Characterized in that.

  According to the present invention, when excavation is performed in curved construction, when the shield machine turns, the earth and sand in the range pressed against the side of the cutter board easily collapses, so the front of the cutter board The resistance applied to the corners is reduced, so that the shield machine can change direction smoothly.

It is the lineblock diagram which looked through the inside of the shield machine of this Embodiment from the side. It is a front view of the cutter board of the shield machine of FIG. It is sectional drawing of the width direction of the main spokes of the cutter board of FIG. It is the side view which looked at a part of cutter board of FIG. 2 along the outer periphery. FIG. 3 is a cross-sectional view of a retractable spoke of the cutter board of FIG. 2 in a width direction. 2A is a cross-sectional view showing a state in which the copy cutter provided on the cutter board shown in FIG. 2 is contracted into the cutter board. FIG. 2B is a sectional view showing that the copy cutter provided on the cutter board shown in FIG. FIG. 4 is a cross-sectional view showing a state in which the second member is extended. It is explanatory drawing which shows the state of the excavation at the time of the curved surface construction of a tunnel by the copy cutter of this Embodiment. It is explanatory drawing which shows the state of the excavation at the time of the curved surface construction of a tunnel by the conventional copy cutter.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings for describing the embodiments, the same components are denoted by the same reference numerals in principle, and the repeated description thereof will be omitted.

  First, the configuration of the shield machine according to the present embodiment will be described with reference to FIG. Here, FIG. 1 is a configuration diagram of the inside of the shield machine according to the present embodiment viewed from the side.

  The shield machine 1 according to the present embodiment, when excavating the ground by pressing and rotating the cutter board 2 against a face, sends the cutter machine 2 to a mud chamber 4 provided in the equipment body 3 behind the cutter board 2. The muddy water is pumped through the mud pipe 5, the muddy water pressure in the muddy water chamber 4 is adjusted to a pressure corresponding to the earth pressure and the underground water pressure of the face to stabilize the face, and the muddy water stored in the muddy water chamber 4 is drained by the mud pipe 6 This is a muddy shield machine that forms a tunnel in the ground while discharging to the outside of the tunnel.

  The cutter board 2 that constitutes the shield machine 1 is a front circular excavating member for excavating the face of the ground, and is rotatable in the forward and reverse directions along the circumferential direction of the equipment body 3 on the front surface of the equipment body 3. It is installed in a state. The cutter board 2 is, for example, of a face plate type. On its front face (the face facing the face), a plurality of types of cutter bits are installed at many locations, and excavation is performed by rotation of the cutter board 2. A hole 4a is formed to take the removed earth and sand into the muddy water chamber 4.

  The front trunk plate 3a and the rear trunk plate 3b constituting the equipment main body 3 of the shield machine 1 are formed of, for example, a cylindrical steel plate. The front body plate 3a and the rear body plate 3b are engaged when the spherical bearing portion on the front end side of the rear body plate 3b comes into contact with the inner peripheral surface on the rear end side of the front body plate 3a. . Behind the rear trunk plate 3b, a tail seal 3c for preventing underground water or the like from entering the equipment main body 3 from the rear part of the equipment main body 3 during excavation work in a frame shape along the inner periphery of the rear trunk plate 3b. Is provided.

  On the front side of the front body plate 3a, a partition wall 7 that divides the inside of the apparatus main body 3 into a face side and an inside of the apparatus is installed at a position retracted from the front side to the inside of the apparatus main body 3. The muddy chamber 4 is provided on the face side of the device main body 3, that is, between the cutter board 2 and the partition 7. The mud chamber 4 is a space (chamber) that takes in the earth and sand excavated by the rotation of the cutter board 2 and mixes with the mud supplied through the mud pipe 5.

  On the other hand, a cutter driving body 10, a plurality of center bending jacks 11a, a plurality of shield jacks 11b, an erector 12, a mud feed pipe 5, and a mud discharge pipe 6 are installed in the machine body 3. Have been.

  The cutter driver 10 is a drive source that rotates the cutter board 2 in the forward and reverse directions. The center bending jack 11a is a device that connects the front trunk plate 3a and the rear trunk plate 3b and corrects the propulsion direction of the shield machine 1. The shield jack 11b is a device that generates a propulsive force for moving the shield excavator 1 forward by taking a reaction force on the segment SG laid on the inner periphery of the tunnel behind the device main body 3. The erector 12 is a device for assembling the segment SG on the inner periphery of the excavated tunnel. The segment SG is composed of, for example, a flat concrete segment or a composite segment (composite structure of concrete and steel), and is installed in a state where a plurality of segments are arranged along the circumferential direction and the axial direction of the tunnel.

  The mud feed pipe 5 is a pipe that supplies muddy water into the muddy water chamber 4, and is formed of, for example, a steel material. The distal end portion (mud outlet) of the mud feeding pipe 5 penetrates through the upper front inside of the partition wall 7 and reaches the muddy water chamber 4. Thereby, the muddy water pumped through the mud feeding pipe 5 is supplied into the muddy water chamber 4 from the upper front inside of the shield machine 1. On the other hand, the rear end of the mud pipe 5 extends toward the tunnel entrance, and through a plurality of mud pumps (not shown) arranged at predetermined intervals on the way, a muddy water layer outside the tunnel is provided. (Not shown). The mud tank is connected to a mud treatment device (not shown) outside the tunnel.

  The mud drain pipe 6 is a pipe for discharging mud water (mixed mud water of excavated earth and sand) in the mud chamber 4 to the outside of the tunnel, and is formed of, for example, a steel material. The tip end (suction port) of the drainage pipe 6 penetrates the lower part in the front of the partition wall 7 and reaches the muddy water chamber 4. As a result, the muddy water in the muddy water chamber 4 is discharged from the lower front inside of the shield machine 1. On the other hand, the rear end of the sludge pipe 6 extends toward the opening of the tunnel, and passes through a plurality of sludge pumps (not shown in FIG. 1) arranged at predetermined intervals on the way. It is connected to the external muddy water treatment device. That is, the muddy water in the muddy water chamber 4 is sent to a muddy water treatment device outside the tunnel through the muddy water pipe 6, where it is separated into earth and sand and muddy water, the specific gravity and viscosity of which are adjusted, and then sent to the muddy water tank. Then, it is again sent to the muddy water chamber 4 (face) through the mud pipe 5.

  Next, the configuration of the cutter board 2 of the shield machine 1 will be described with reference to FIGS. Here, FIG. 2 is a front view of a cutter board of the shield machine shown in FIG. 1, FIG. 3 is a cross-sectional view of a main spoke of the cutter board of FIG. 2 in a width direction, and FIG. 4 is a part of the cutter board of FIG. 5 is a cross-sectional view in the width direction of the retractable spokes of the cutter board of FIG. 2, and FIG. 6A is a view in which a copy cutter provided on the cutter board of FIG. 2 is retracted into the cutter board. FIG. 6B is a cross-sectional view showing a state in which the copy cutter provided on the cutter board of FIG. 2 is extended to the maximum from a side surface of the cutter board, and FIG. 7 is a copy cutter of the present embodiment. It is explanatory drawing which shows the state of the excess digging at the time of the curved surface construction of a tunnel.

  As described above, in the present embodiment, the face plate type is adopted as the cutter board 2, and the center hub portion 2-1 and the four main portions radially extending from the hub portion 2-1 toward the outer periphery are used. The spokes 2-2, the retractable spokes 2-3 positioned between the main spokes 2-2 and slidable in the front-rear direction, and closing the gaps between the main spokes 2-2 and the retractable spokes 2-3. A face plate portion 2-4, which is a plate-like steel material, and an outer peripheral ring portion 2-5 connecting the tip portions of the main spokes 2-2 and the retractable spokes 2-3 are provided. Various cutter bits (center bit 21, ripper-type bits 22a and 22b, leading bit 24, outer peripheral bits 25 and 26, scraper tooth 30, scraper tooth 30, outer peripheral scraper tooth) which will be described later 30a) are arranged in plurality. The hub 2-1, the main spokes 2-2, and the face plate 2-4 are formed integrally with each other.

  A center bit 21 for excavating earth and sand is installed in a central hub portion 2-1 of the cutter board 2.

  As shown in FIGS. 2 and 3, the main spokes 2-2 are provided with a plurality of ripper-type bits 22a for excavating earth and sand in a line in the longitudinal direction. Further, a plurality of scraper teeth 30 for taking in excavated shear are arranged along the longitudinal direction on both sides in the width direction of the main spokes 2-2. As shown in FIG. 4, an outer peripheral scraper tooth 30 a for maintaining the outer diameter of the excavation is installed at a position of the end of the main spoke 2-2 which is located on the outer periphery of the cutter board 2 among these scraper teeth 30. Have been. In the present embodiment, the installation height of the ripper-type bit 22a (height from the front surface of the cutter board 2) is 150 mm, and the installation height of the scraper tooth 30 and the outer peripheral scraper tooth 30a is 70 mm.

  As shown in FIGS. 2 and 5, the retractable spokes 2-3 are provided with a plurality of ripper-type bits 22b and a plurality of scraper teeth 30 in the same manner as the main spokes 2-2. As described above, the retractable spokes 2-3 are slidable in the front-rear direction, and at the retracted position where the retractable spokes are retracted, the tips of the ripper-type bit 22b and the scraper tooth 30 are substantially the same as those of the cutter board 2. The position is lower than the front surface (that is, the surface of the main spoke 2-2 or the face plate portion 2-4). In the forward position, the surface of the retractable spoke 2-3 is at the same position as the surface of the main spoke 2-2 and the surface of the face plate portion 2-4. The installation height of the scraper tooth 30 at this time is the same as the installation height of the scraper tooth 30 of the main spoke 2-2, but the installation height of the ripper type bit 22b is the same as the installation height of the ripper type bit 22a of the main spoke 2-2. It is 100 mm, which is lower than the installation height.

  As shown in FIG. 2, a plurality of preceding bits 24 for earth and sand digging are installed on the face plate portion 2-4.

  As shown in FIGS. 2 and 4, a plurality of outer peripheral bits 25 and 26 for excavating two types of earth and sand are provided on an outer peripheral ring portion 2-5 which is an outer periphery of the cutter board 2.

  Here, as shown in FIG. 2, at the outer end of each of the four main spokes 2-2 arranged at every rotation angle of 90 °, there is an extra excavation or a shield excavator 1 when constructing a curved surface of a tunnel. Copy cutters (a first copy cutter 31a and a second copy cutter 31b) for controlling the posture of the cutter board 2 are provided so as to be extendable from the side of the cutter board 2. That is, in FIG. 2, a first copy cutter 31a is provided at an outer end of two main spokes 2-2 extending in the vertical direction of the cutter board 2, and two main spokes 2-2 extending in the lateral direction of the cutter board 2 are provided. A second copy cutter 31b is provided at an outer end of the spoke 2-2.

  As shown in FIG. 6, the first copy cutter 31a is mounted to be driven by a hydraulic cylinder 32 to extend obliquely forward from the side surface of the cutter board 2. The rod 32 a of the hydraulic cylinder 32 is fixed to the rear end of the copy cutter 17. A piston (not shown) that reciprocates the rod 32a is slidably provided in a cylinder chamber (not shown) formed in the hydraulic cylinder 32. Further, the hydraulic cylinder 32 is provided with a pipe 32b for introducing oil into one chamber and the other chamber of a cylinder chamber partitioned by a piston. Thereby, the rod 32a reciprocates via the piston by controlling the hydraulic pressure introduced into each room from the pipe 32b, whereby the first copy cutter 31a extends obliquely forward from the cutter board 2, or It retracts into the cutter board 2.

  In the present embodiment, the rod 32a is driven by hydraulic pressure. However, various other driving methods such as a rack and pinion method using a stepping motor can be adopted.

  Here, the first copy cutter 31a is retracted to the side of the cutter board 2 as shown in FIG. 6A, and is extended from the side of the cutter board 2 as shown in FIG. 6B. It can be expanded and contracted with the state. In the present embodiment, the maximum extension dimension of the first copy cutter 31a shown in FIG. 6B is, for example, 200 mm.

  The first copy cutter 31a adjusts the amount of oil introduced into the cylinder chamber of the hydraulic cylinder 32 so that the retracted position shown in FIG. 6A and the maximum extended position shown in FIG. It is also possible to extend to an arbitrary position on the way. Therefore, at the time of overdigging, the first copy cutter 31a is extended to a length corresponding to a necessary overdigging height. In addition, when digging, a simulator is used to secure the amount of digging in three dimensions.

  Here, as shown in FIG. 6B, the amount of protrusion of the first copy cutter 31a forward (the amount of protrusion from the front surface of the cutter board 2) at the time of maximum extension is arranged on the outer periphery of the cutter board 2. It is the same as the installation height of the outer peripheral scraper tooth 30a (that is, the cutter bit having the lowest installation height among the cutter bits arranged on the outer periphery of the cutter board 2).

  In the present embodiment, as described above, since the installation height of the outer peripheral scraper tooth 30a is 70 mm, the projection amount of the first copy cutter 31a at the time of maximum extension is 70 mm.

  As described above, when the first copy cutter 31a is provided so as to extend obliquely forward from the cutter board 2 and the amount of forward projection is the same as the installation height of the outer scraper tooth 30a, as shown in FIG. When the excavation is performed in the curve construction, the ground in the depth of the earth and sand in the region R1 from the front surface of the cutter board 2 to the extra excavation portion (a range indicated by a thick triangle in FIG. 7) is excavated. Accordingly, when the shield machine 1 changes direction, the earth and sand in a range pressed against the side surface of the cutter board 2, more specifically, the side surface of the outer peripheral scraper tooth 30 a easily collapses. Such resistance is reduced, and the direction can be changed smoothly.

  Further, since the amount of protrusion of the first copy cutter 31a forward is the same as the installation height of the outer scraper tooth 30a, even if the first copy cutter 31a is protruded at the position where the curve starts to be bent, extra cutting is performed. There is no delay in the start position of the. As a result, the rear end of the rear trunk plate 3b of the shield machine 1 does not come into contact with the ground inside the curved portion, so that it is possible to smoothly change the direction at this point as well. Therefore, the amount of excavated earth and sand and the filler injected into the outside of the shield machine 1 due to excessive excavation do not increase.

  In the present embodiment, since the outer peripheral scraper tooth 30a is the cutter bit having the lowest installation height among the cutter bits disposed on the outer periphery of the cutter board 2, the first copy cutter 31a The amount of forward projection is the same as the installation height of the outer peripheral scraper tooth 30a. However, if the cutter bit having the lowest installation height is other than the outer peripheral scraper tooth 30a, the same height as the installation height of the cutter bit is used.

  Further, in the present embodiment, the amount of protrusion of the first copy cutter 31a from the front surface of the cutter board 2 is determined by the outer scraper tooth 30a (that is, the cutter bit arranged on the outer circumference of the cutter board 2). , Which is the same as the installation height of the cutter bit having the lowest installation height, but may protrude forward from the installation height. That is, the protrusion amount of the first copy cutter 31a may be equal to or more than the installation height of the outer peripheral scraper tooth 30a.

  Here, it is also conceivable that the copy cutter is arranged on the front surface of the cutter board 2 and projects diagonally forward toward the outside in the radial direction of the cutter board 2.

  However, since various cutter bits are densely arranged on the front surface of the cutter board 2, especially on the front surface of the main spokes 2-2, it is difficult to arrange the copy cutter so as to protrude diagonally forward from the viewpoint of space. is there.

  Further, it is desirable that the copy cutter, including the jack that makes the copy cutter protrude and retract, fit within the width (thickness) of the cutter board 2. Even if the rear end projects into the chamber inevitably, the amount of protrusion is made as small as possible. There is a need. When the copy cutter projects from the front surface of the cutter board 2, the projection length becomes longer than when the copy cutter projects from the side face of the cutter board 2. As a result, the jack becomes longer and the rear end projects into the chamber. The amount increases.

  Further, when the copy cutter is arranged on the front surface of the cutter board 2, unlike the case where the copy cutter is arranged on the side surface, the copy cutter is constantly pressed against the ground during excavation, so that the wear on the front surface of the copy cutter progresses, which is necessary during extension. It may not be possible to dug to the position.

  For this reason, in the present embodiment, the copy cutter, that is, the first copy cutter 31a is provided on the side surface of the cutter board 2 so as to extend obliquely forward.

  Now, in FIG. 2, the second copy cutter 31 b provided at the outer ends of the two main spokes 2-2 extending in the lateral direction of the cutter board 2 extends and contracts vertically from the side surface of the cutter board 2. The maximum elongation dimension is, for example, 100 mm.

  Since the second copy cutter 31b is a conventional copy cutter that expands and contracts vertically from the side surface of the cutter board 2, the shield excavation of the present embodiment provided with the above-described first copy cutter 31a is provided. The machine 1 may not be provided. However, when the soft ground is constructed on a curved surface, the direction of the shield machine 1 can be smoothly changed even if the second copy cutter 31b is dug, so that in such a case, the second Two copy cutters 31b may be used.

  As described above, the invention made by the inventor has been specifically described based on the embodiments. However, the embodiments disclosed in the present specification are illustrative in all points, and are limited to the disclosed technology. Not something. That is, the technical scope of the present invention is not to be interpreted restrictively based on the description in the above embodiment, but should be interpreted according to the description of the claims. And any modifications that do not depart from the gist of the claims and the technology equivalent to the technology described in the claims.

  For example, the maximum extension size and the amount of forward projection of the first copy cutter 31a, the maximum extension amount of the second copy cutter 31b, the installation height of each cutter bit installed on the cutter board 2, and the like in the present embodiment. Are merely examples, and the present invention is not limited to these values.

  In the above description, the case where the present invention is applied to a mud pressure type shield excavator has been described.However, the present invention is not limited to this, and may be applied to other shield excavators such as a mud pressure type shield excavator. Can be. Further, the cutter board is not limited to the face plate type, but can be applied to a spoke type.

DESCRIPTION OF SYMBOLS 1 Shield excavator 2 Cutter board 2-1 Hub part 2-2 Main spoke 2-3 Retractable spoke 2-4 Face plate part 2-5 Outer ring part 3 Equipment main body 3a Front trunk plate 3b Rear trunk plate 4 Mud chamber 4a Hole 21 center bit 22a, 22b ripper type bit 24 leading bit 25, 26 outer bit 30 scraper tooth 30a outer scraper tooth 31a first copy cutter (copy cutter)
31b Second copy cutter (copy cutter)

Claims (4)

A cutter board installed on a shield machine that excavates the ground and builds a tunnel,
A plurality of cutter bits arranged on the front surface of the cutter board, and excavating a face in the traveling direction,
A copy cutter that is arranged to be extendable and contractable from the side surface of the cutter board and performs extra excavation in the curved surface construction of the tunnel,
The copy cutter is
The cutter bit extends obliquely forward from the side surface of the cutter board, and the amount of protrusion from the front face of the cutter board at the time of maximum extension is the installation height of the lowest installation height disposed at the outer periphery of the cutter board. That's it,
A cutter board characterized by the following. The amount of extension of the copy cutter from the side surface of the cutter board is equal to or more than the necessary extra depth at the time of designing the cutter board,
The installation angle of the copy cutter is set such that when the copy cutter is extended to the installation height of the cutter bit disposed on the front surface of the cutter board, the leading end reaches the amount of extension from the side surface. ,
The cutter board according to claim 1, wherein:   A shield excavator comprising the cutter panel according to claim 1 or 2 rotatably provided on a front surface of an apparatus body. A tunnel excavation method using a shield machine that excavates the ground and builds a tunnel,
The copy cutter arranged on the side of the cutter board installed in the shield machine, the amount of protrusion from the front of the cutter board, the installation height of the lowest installation height of the cutter bit arranged on the outer periphery of the cutter board It is arranged to be able to extend and contract diagonally forward of the cutter board so as to be more than
Performing extra excavation in the curve construction of the tunnel using the copy cutter, forming a space necessary for the shield machine to bend,
It is characterized by a tunnel excavation method using a shield machine.

Images