JP6685214B2 - Tunnel excavation method and tunnel excavator - Google Patents

Description

  The present invention relates to a tunnel excavation method and a tunnel excavator, and more particularly, to an excavation technique when a bad ground is encountered.

It is a tunnel excavator that rotates the cutter head to excavate all the ground in a cross section, by a gripper pressed against the mine wall, or by a jack or gripper pressed against a lining body constructed by assembling segments etc. The tunnel construction method (TBM method) that uses tunnel boring machines (TBM) that obtains reaction force for excavation is adopted when a tunnel is built in rock and a short construction period is required. Known as.
However, in the TBM method, when encountering poor ground such as soft ground, the cutter head cannot excavate due to the collapse of the cutting face, and the supporting face such as concrete spraying cannot be carried out by the cutting face, making it impossible to proceed with digging. There was a case.

  In such a case, for example, in Patent Document 1, the cutter head is provided with an opening that allows the inside of the excavator body to communicate with the face of the ground, and when the soft ground is encountered, the excavation is temporarily stopped. There is disclosed a tunnel excavator for improving the ground, and then carrying equipment and a small machine, which are separate from the tunnel excavator, from the opening to the face of the face to excavate the soft ground.

  Further, in Patent Document 2, a rotary disk cutter of a tunnel boring machine is divided into an outer peripheral cutter head and a central cutter head, and the latter is detachably installed from the former, and normally, the outer peripheral portion and the central cutter head are used for excavation. However, there is disclosed a tunnel boring machine in which the central cutter head is separated in an emergency that cannot be normally handled, and the face opened forward is allowed to be pre-excavated from the inside of the tunnel boring machine.

JP, 2015-121034, A Japanese Patent No. 5642130

Here, when excavating a large-diameter tunnel, a self-propelled construction machine such as a backhoe is inserted from the opening of the cutter head to the face of the face to excavate soft ground, as suggested in Patent Documents 1 and 2 above. Can be applied, but such a construction method is not suitable for excavating a tunnel because the exchanging between excavation by the cutter head of TBM and excavation by a self-propelled construction machine cannot be performed efficiently. There was a problem.
The present invention has been made in view of the above problems and facilitates excavation by a cutter head of a tunnel excavator and auxiliary excavation by an auxiliary excavator such as a self-propelled construction machine when excavating a tunnel by a TBM method. It is an object of the present invention to provide a tunnel excavation method and a tunnel excavation machine that can be changed to (in a short time) and can efficiently break through a poor ground.

Therefore, in the tunnel excavation method according to the present invention, in the first aspect, the cutter head is rotatably mounted on the front part of the body to obtain a reaction force for propelling it from the pit wall or the lining body. A method of excavating a tunnel by means of: installing an auxiliary excavator for excavating by a working device at the tip of an arm in the body, and providing an opening that can be opened and closed in the cutter head, and the opening is opened. And an auxiliary excavation step in which the arm body is protruded forward to excavate the ground by the working device to advance the tunnel. The opening from which the arm is projected is configured to be openable / closable by an opening / closing door that is pushed open toward the front of the cutter head, and the auxiliary excavation step directs the opening / closing door toward the front of the cutter head. Including an opening process of pushing open.

In the tunnel excavation method according to the present invention, in a second aspect thereof, a cutter head is rotatably mounted on a front portion of a body to obtain a reaction force for propelling from a tunnel wall or a lining body by a tunnel excavator. A method of excavating, wherein an auxiliary excavator for excavating by a working device at the tip of an arm is installed in the body, and an opening portion that can be opened and closed is provided in the cutter head, and the opening portion is opened. It includes an auxiliary excavation step of projecting an arm forward and excavating the ground by the working device to advance the tunnel. The opening is configured to be opened and closed by the open door closing, the auxiliary drilling step includes a retracting step of retracting the tunnel boring machine, and a open Keru opening step of the door after the retraction step.

On the other hand, the tunnel excavator according to the present invention, as one aspect thereof, is a tunnel excavator in which a cutter head is rotatably mounted on a front portion of a body to obtain a reaction force for propelling it from a pit wall or a lining body. There, an auxiliary excavator for excavating with a working device at the tip of the arm is arranged in the body, and an opening part that can be opened and closed is provided in the cutter head, and the arm part is opened forward from the opened opening part. The work device is constructed so that the ground can be excavated and tunneling can be performed. Here, the opening from which the arm body is projected is configured to be opened and closed by an opening / closing door that is pushed open toward the front of the cutter head.

According to the tunnel excavation method of the present invention, instead of excavation by the cutter head, the arm of the auxiliary excavator can be protruded from the opening of the cutter head to excavate the ground by the working device at the tip of the arm. Therefore, when a bad ground is encountered, it can be excavated by an auxiliary excavator instead of excavating by the cutter head. Therefore, it is possible to break through the bad ground and proceed through the tunnel.
In addition, the auxiliary excavator can perform excavation by protruding the arm body from the opening of the cutter head, and easily perform excavation by the cutter head of the tunnel excavator and auxiliary excavation by the auxiliary excavator (in a short time). ) Because it can be changed, it is possible to efficiently break through bad ground.

It is a top view of TBM in an embodiment of the present invention. It is a side view of TBM in an embodiment of the present invention. It is a front view of the cutter head in the embodiment of the present invention. It is a cross-sectional view of TBM which shows the installation structure of the earth discharging conveyor in the embodiment of the present invention. It is a top perspective view of the excavator (auxiliary excavator) in the embodiment of the present invention. It is a bottom perspective view of the excavator in the embodiment of the present invention. It is a cross-sectional view showing a clamp structure of the clamp box of the excavator in the embodiment of the present invention. It is a rear view showing the rear wheel structure of the clamp box of the excavator in the embodiment of the present invention. It is a flow chart which shows the procedure of tunnel excavation by TBM in an embodiment of the present invention. It is a figure for demonstrating the excavation state (standard excavation process) by the cutter head in embodiment of this invention. It is a flowchart which shows the procedure of the auxiliary excavation process in embodiment of this invention. It is a flow chart which shows a procedure of an auxiliary drilling preparation process in an embodiment of the present invention. It is a figure for demonstrating the ground improvement work (ground improvement process) when a bad ground is encountered in embodiment of this invention. It is a figure for demonstrating the preparatory work (retraction preparation process) before retracting a cutter head in an embodiment of the present invention. It is a figure for demonstrating the retracting | retreat work (retracting process) of the cutter head and the spraying work (ground improvement process, spraying process) in embodiment of this invention. It is a figure for demonstrating the preparatory work (auxiliary excavation preparation process) before starting excavation by the excavator in the embodiment of the present invention. It is a figure for demonstrating the work which advances an excavator in the embodiment of this invention (excavator advance process), and the discharge work of the earth and sand by an excavator (sludge discharge process by an excavator). It is a figure for demonstrating the earth-and-sand work by manual work (sliding discharge process by manual work) in the installation place of the skirt part in embodiment of this invention. In the embodiment of the present invention, the operation of opening the opening of the cutter head (opening step), the operation of arranging the skirt portion on the earth discharging conveyor (skirt portion arranging step), and the operation of transferring the earth discharging conveyor (conveyor transferring step) ) Is a diagram for explaining FIG. FIG. 6 is a front view of the cutter head for explaining a state (opening step) in which the entire area of the opening of the cutter head is opened in the embodiment of the present invention. It is a figure for demonstrating the work which advances an excavator in an embodiment of this invention (advance process), and the initial stage of the excavator's excavation (auxiliary excavation process). It is a figure for demonstrating the excavation state which extended the sliding jack in the excavator excavator excavation (auxiliary excavation process) in the embodiment of the present invention. It is a figure for demonstrating the propulsion state (propulsion process) of TBM by the gripper rearrangement in an embodiment of the present invention, and the connection work (connection process) of a fuselage. It is a figure for demonstrating the spraying work (nozzle mounting process, spraying process) of concrete etc. which used the excavator in embodiment of this invention.

Hereinafter, embodiments of a tunnel excavation method and a tunnel excavation machine according to the present invention will be described with reference to the drawings.
First, a tunnel boring machine (TBM) 100 as one aspect of a tunnel excavator according to the present invention will be described with reference to FIGS. 1 to 8.

The TBM 100 is a tunnel excavator in which a cutter head 120 is rotatably mounted on a front portion of a body 110, and a reaction force for pushing a gripper (gripper shoe) 132 against a pit wall to obtain a thrust is obtained. Is a small-sized full-section tunnel excavator of about 3 to 4 m. However, the diameter of the TBM 100 is not limited to 3 m to 4 m, and the same structure as this embodiment can be applied to the TBM 100 having a larger diameter.
The cylindrical body 110 is composed of a front body 111 and a rear body 112, and a cutter head 120 is attached to a front portion of the front body 111 by a main bearing 113 so as to be rotatable.

A plurality of roller cutters 121a for shearing and breaking the natural ground are pivotally attached to the front part of the cutter head 120, and scrapers 121b for scraping excavation scraps accumulated under the cutting face are arranged at equal intervals on the peripheral edge. Behind 121b, a bucket (not shown) for picking up and taking in the excavation scrap is provided.
Then, the cutter head 120 is rotationally driven about the axis of the body 110 by the cutter head drive motor 122.

The fitting portions of the front body 111 and the rear body 112 are connected by a plurality of articulate jacks 115, and the front body 111 is bent with respect to the rear body 112 by selectively expanding and contracting the articulate jacks 115. It is configured to be able to.
The cutter head 120 is rotatably supported on the front part of the main beam 130 extending to the rear of the cutter head 120, and the gripper device 133 is supported on the rear part of the main beam 130 so as to be slidable in the front-rear direction. .

The gripper device 133 is a device that pushes the gripper 132 against the pit wall to obtain a digging reaction force by radially extending the gripper 132 by the gripper jack 131.
One end of the thrust jack 140 is connected to the gripper device 133, and the other end is connected to the main beam 130 in front of the gripper device 133.
Further, at the rear part of the rear body 112, an erector device 160 for assembling the support structure 161 to the inner wall surface (mine wall) 150 of the tunnel is provided.

  In addition, a hopper chute 170 for receiving the earth and sand (sliding) taken into the cutter head 120 is provided in the front part of the main beam 130, and further, a conveyor case 139 having a rectangular cross section provided integrally with the main beam 130. An earth discharging conveyor (belt conveyor) 180 is disposed inside, and the earth discharging conveyor 180 carries out the earth and sand received by the hopper chute 170 to the rear.

Further, a rear support 190 is provided on the main beam 130 on the rear side of the gripper device 133 so as to come into contact with the pit wall 150 and receive a rolling reaction force from the pit wall 150 during the projecting operation.
Further, behind the TBM 100, a trailing carriage (not shown) equipped with a hydraulic device, electric equipment, an earth discharging device, a water supply equipment, etc. is connected.

The basic excavation cycle (standard excavation process, standard tunnel excavation process) by the TBM 100 is as follows.
First, in a state in which the gripper 132 is pressed against the mine wall and the rear support 190 is contracted, the thrust jack 140 is extended while excavating the natural ground by the cutter head 120 that is driven to rotate, thereby digging the tunnel (tunnel digging). Process).
The TBM 100 of the present embodiment is a form in which the thrust jack 140 is extended while the gripper 132 is pressed against the mine wall to dig a tunnel, but the mine wall is a lining body composed of segments or the like. If it is covered, the thrust jack 140 is extended while the gripper 132 is pressed against the lining body to extend the tunnel, or the thrust jack is directly pressed against the lining body. It is possible to form a tunnel by extending 140.
In addition, as shown in FIGS. 1 and 2, a plurality of propulsion jacks 171 are circumferentially spaced from each other in the peripheral portion of the rear body 112, and the rod tip of the propulsion jack 171 is covered with a segment or the like. When the propulsion jack 171 is extended while being brought into contact with the work body, a digging reaction force can be obtained. That is, the TBM 100 digs into the tunnel by obtaining a reaction force for propelling it from the pit wall or the lining body.

When the thrust jack 140 is extended to the set length, the rotational driving of the cutter head 120 is stopped, the gripper jack 131 is contracted to separate the gripper 132 from the pit wall, while the rear support 190 is extended to extend the pit wall 150. Abut. Then, in such a state, the thrust jack 140 is contracted to pull the gripper device 133 (the gripper jack 131 and the gripper 132) toward the cutter head 120 side, and then the gripper jack 131 is extended to press the gripper 132 against the pit wall. The rear support 190 is contracted (gripping tool rearrangement process).
When the gripper rearrangement is completed, the thrust jack 140 is extended while rotating the cutter head 120 to restart the tunnel excavation, and the tunnel excavation step and the gripper rearrangement step are repeated.
That is, in the standard excavation process of excavating the tunnel by the cutter head 120, the thrust jack 140 is extended while the excavation reaction force is obtained by the gripper 132 to press the cutter head 120 against the face, and the cutter head 120 that is driven to rotate is grounded. The tunnel is excavated by repeating the tunnel excavation process of excavating the tunnel and the gripper reshuffling process of moving the pressing position of the gripper 132 against the mine wall to the side closer to the face.

In addition to the basic configuration described above, the TBM 100 is an auxiliary excavator for performing tunnel excavation on behalf of the cutter head 120 when encountering a poor ground (soft ground) where it is difficult to excavate the entire cross section by the cutter head 120. The excavator 200 is arranged in the body 110. As the auxiliary excavator, a bucket excavator, a breaker excavator, or the like can be used in addition to the excavator.
The excavator 200 is an excavator in which a working device is attached to the tip of an arm, and will be described in detail with reference to FIGS. 5 to 8.

The main beam 130 is integrally provided with a pair of left and right rails 135 extending along the front-rear direction of the TBM 100, and the machine body of the excavator 200 is movably supported by the rails 135.
The excavator 200 includes a clamp box 210 that constitutes a main body of the machine, a support frame 220 that is supported so that the clamp box 210 can be raised and lowered, and a boom 230 that is slidably supported by the support frame 220. , A bucket 240 that is attached to the tip of the boom 230 so as to be tiltable, and the like.
In the present embodiment, the arm of the excavator 200 as an auxiliary excavator is formed by the support frame 220 and the boom 230.

The clamp box 210 includes a pair of front wheels 211 and a pair of rear wheels 212 for moving in the front-rear direction along the rails 135.
Further, the clamp box 210 includes four pairs of combinations of an inner clamp 213 and an outer clamp 214 that sandwich the rail 135 between the front wheel 211 and the rear wheel 212 from the left and right. The clamp box 210 can be fixed to any position above, and braking can be applied when the clamp box 210 is moved and stopped.

The front wheel 211 is rotatably supported at the left and right ends of the clamp box 210 on the support frame 220 side (front side) so as to be rotatable around a rotation axis extending in the left-right direction, and its tread surface rotates while contacting the head of the rail 135.
The front wheel 211 is a drive wheel that is rotationally driven by a hydraulic motor (not shown). When the front wheel 211 is rotationally driven, the clamp box 210 self-propels on the rail 135 and moves in the front-rear direction.

On the other hand, the rear wheel 212 is rotatably supported by the left and right ends of the clamp box 210 on the opposite side (rear side) to the side on which the support frame 220 is provided.
Outer side surface of each rail 135 (the surface opposite to the surface where the two rails 135 face each other)
The groove 136 is recessed so as to extend along the front-rear direction, and the cross section of the groove 136 is parallel to the bottom surface and the open surface, and the bottom surface side is narrower than the open surface side (expands toward the open surface). Form a trapezoid. The rear wheel 212 is a non-driving wheel configured such that the tread surface comes into contact with the upper inclined surface 136a of the groove 136 and rotates.

The unit of the rear wheel 212 is swingably supported with respect to the clamp box 210, and by extending the rear wheel pressing jack 218, the tread surface of the rear wheel 212 is pressed against the upper inclined surface 136a, and the rear wheel pressing jack 218 is moved. By contracting, the tread surface of the rear wheel 212 is separated from the upper inclined surface 136a.
That is, in the state where the rear wheel pressing jack 218 is extended and the tread surface of the rear wheel 212 is pressed against the upper inclined surface 136a, the rotation axis of the rear wheel 212 is parallel to the upper inclined surface 136a and diagonally intersects the horizontal plane. When the rear wheel pressing jack 218 is contracted, the rotation axis of the rear wheel 212 swings outward around the swing axis, and the tread surface of the rear wheel 212 is separated from the upper inclined surface 136a.

According to such a configuration, in the state where the rear wheel pressing jack 218 is extended, the force in the direction of lifting the rear side of the clamp box 210 acts as a force for pressing the tread surface of the rear wheel 212 against the upper inclined surface 136a, and the front side. Further, the rear side of the clamp box 210 that supports the support frame 220, which is a heavy object, is prevented from floating around the front wheel 211 as a fulcrum.
Further, by contracting the rear wheel pressing jack 218, the unit of the rear wheel 212 is retracted to the outside, and in this state, the clamp box 210 can be attached to and detached from the rail 135. That is, the rear wheel pressing jack 218 is held in the extended state except when the clamp box 210 is detached.

The inner clamp 213 and the outer clamp 214 are a mechanism for fixing the clamp box 210 at an arbitrary position in the front-rear direction by pressing the rail 135 so as to sandwich the rail 135 from the left and right.
The outer clamp 214 has a trapezoidal portion 214a that matches the shape of the groove 136, and the trapezoidal portion 214a is fitted into the groove 136 by extending the outer rail clamp jack 215 provided for each combination of the pair of left and right outer clamps 214. The trapezoid portion 214a is swingably supported by the clamp box 210 so that the trapezoidal portion 214a is separated from the groove portion 136 by contracting the outer rail clamp jack 215.

On the other hand, the inner clamp 213 has a flat pressing surface 213a, and by extending the inner rail clamp jack 216 provided for each combination of the pair of left and right inner clamps 213, the trapezoidal portion 214a of the outer clamp 214 with the rail 135 interposed therebetween. The pressing surface 213a is pressed against the inner surface of the rail 135 which faces the rail 135, and the inner rail clamp jack 216 is contracted, so that the pressing surface 213a is separated from the inner surface of the rail 135. It is swingably supported with respect to 210.
That is, when it is desired to fix the position of the clamp box 210 during excavation by the excavator 200, the outer rail clamp jack 215 and the inner rail clamp jack 216 are extended to press the inner clamp 213 and the outer clamp 214 against the rail 135. The frictional resistance prevents the clamp box 210 from moving in the front-rear direction.

On the other hand, when the clamp box 210 is moved along the rail 135, the outer rail clamp jack 215 and the inner rail clamp jack 216 are contracted so that the inner clamp 213 and the outer clamp 214 are clamped (pressed against the rail 135). When released, the front wheels 211 are driven to rotate in this state.
In the clamped state by the inner clamp 213 and the outer clamp 214, the trapezoidal portion 214a of the outer clamp 214 is fitted into the groove 136 to position the clamp box 210 in the vertical direction, and at this time, the treads of the front wheels 211 and 211 are railed. It is configured to be in a floating state (non-contact state) from the heads of 135 and 135.

Further, the support frame 220 includes a base end portion 220a that is swingably supported around a vertical center (left and right direction) with respect to the front center of the clamp box 210, and a horizontal axis (up and down direction) with respect to the tip of the base end portion 220a. ) Is swingably supported by the frame portion 220b.
Then, the other ends of the pair of left and right turning jacks 221 whose one ends are connected to the left and right ends on the front side of the clamp box 210 are connected to the left and right side faces of the base end 220a, and one of the turning jacks 221 is extended and the other is contracted. As a result, the base end portion 220a is configured to swing around the vertical axis (left-right direction).

Further, the elevation jack 222 has one end connected to an upper portion of the base end portion 220a and the other end connected to an upper portion of the frame portion 220b. By extending and contracting the elevation jack 222, the frame portion 220b swings in the vertical direction. Move.
Further, by expanding and contracting the sliding jack 223 provided between the support frame 220 (frame portion 220b) and the boom 230, the protruding length of the boom 230 from the front end of the support frame 220 (frame portion 220b), that is, The length of the arm from the clamp box 210 to the bucket 240 is variable.

Further, the bucket 240 is provided with a plurality of teeth 240c outside the edge portion 240a and the bottom plate 240b, and is supported so as to be swingable around the horizontal axis (vertical direction) with respect to the tip of the boom 230.
The bucket tilt jack 224 has one end connected to the boom 230 and the other end connected to the bucket 240, and the bucket 240 is tilted by expanding and contracting the bucket tilt jack 224.

When tunnel excavation is performed using the excavator 200 having the above configuration, the support frame 220 and the boom 230 are projected from the opening of the cutter head 120 toward the face of the face of the boom while the clamp box 210 is fixed to the rail 135. The ground in front of the cutter head 120 is excavated by the bucket 240 attached to the tip of the.
An opening / closing door 123 that can be opened and closed is formed in a predetermined area in the center of the cutter head 120, and the support frame 220 and the boom 230 can be inserted into an opening 123a (see FIG. 20) that is opened and opened. It

Further, when the support frame 220 and the boom 230 are projected from the opening 123a of the cutter head 120 to the face of the face and the ground is excavated by the bucket 240, the excavated earth and sand are placed on the conveying surface of the earth discharging conveyor 180 and discharged rearward. To do so, the tip unit 180a of the earth discharging conveyor 180 is projected to the lower front portion of the cutter head 120.
In order to allow the earth discharging conveyor 180 to project, an opening 128 through which the earth discharging conveyor 180 is inserted is continuous in the radial direction of the cutter head 120 from the opening 123a opened when the opening / closing door 123 is opened. As described above, the cutter head 120 is provided (see FIG. 20), and the opening 128 for inserting the earth discharging conveyor 180 is configured to be opened by removing the face plate.

The opening 128 for inserting the soil discharging conveyor 180 is one of the scrapers 121b (buckets) arranged at a predetermined angular interval (for example, an arbitrary angular interval such as 90 deg interval, 180 deg interval) on the peripheral edge. One of the scrapers 121b (121b1) is configured to be removable, and the face plates 127a to 127c between the removable scraper 121b1 and the opening / closing door 123 are configured to be removable. .
That is, when excavating by the cutter head 120, the opening / closing door 123 is closed and the scraper 121b1 and the face plates 127a-127c are attached to the cutter head 120.

On the other hand, when excavating by the excavator 200, the angular position of the cutter head 120 is set so that the scraper 121b1 is located at the lower end, the opening / closing door 123 is opened, and the scraper 121b1 and the face plates 127a-127c are removed from the cutter head 120.
Then, the support frame 220 and the boom 230 are projected toward the face of the face from the opening 123a opened and opened by the opening / closing door 123, and the soil discharging conveyor 180 is installed in the opening 128 opened by removing the scraper 121b1 and the face plates 127a-127c. It is inserted and the tip of the soil discharging conveyor 180 is projected to the lower front portion of the cutter head 120.

The soil discharging conveyor 180 is configured to be able to be pushed out in a direction approaching the cutter head 120 from a standard position (first position, a position when excavating by the cutter head 120) behind the cutter head 120.
Further, when the soil discharging conveyor 180 is pushed toward the cutter head 120, the conveying surface is set to be substantially horizontal before the pushing. The tip unit 180a of the soil discharging conveyor 180 has a tip end side with the base end side as a swing axis. Then, the conveying surface of the leading end unit 180a is inclined forward (toward the cutting face) so as to form a downward slope.
Then, in this state (the second position, the position at the time of excavation by the excavator 200), the tip unit 180a is inserted into the opening 128 where the scraper 121b1 and the face plates 127a-127c are removed and opened, and the front lower part of the cutter head 120 is inserted. Configured to stick out.

Next, an aspect of a procedure of tunnel excavation by the TBM 100 equipped with the above-described excavator 200 as an auxiliary excavator will be described.
The flowchart of FIG. 9 shows a basic procedure of tunnel excavation by the TBM 100.
In the tunnel excavation, first, a standard excavation step (S1) is performed in which the cutter head 120 excavates the tunnel.

That is, in the tunnel excavation by the TBM 100, the thrust jack 140 is extended while the cutter head 120 is rotationally driven to advance until a bad ground is encountered, and when the thrust jack 140 is fully extended, the gripper 132 is separated from the well wall. After that, the thrust jack 140 is contracted to draw the gripper 132 toward the cutter head 120 side, and then the gripper 132 is pressed against the pit wall again, and the thrust jack 140 is extended and digging while the digging reaction force is obtained by the gripper 132. This is repeated (standard excavation process).
In addition, when the TBM 100 obtains a propulsive reaction force by directly pressing the thrust jack 140 against the lining body configured by the segment or the like, the thrust jack 140 is directly pressed against the lining body. When the thrust jack 140 is fully extended, the thrust jack 140 is separated from the portion pressed against the lining body and then contracted, and then the thrust jack 140 is pressed again against the lining body ( That is, the position of the lining body against which the thrust jack 140 is pressed is rearranged), and the thrust jack 140 is extended and digging while obtaining the digging reaction force from the lining body (standard excavation process).
Further, in the tunnel excavation by the cutter head 120, the support 161 is assembled to the mine wall 150 by the erector device 160, and concrete is sprayed on the mine wall 150 on which the support 161 is installed for reinforcement.

When a bad ground such as soft ground is encountered while the tunnel is being advanced by the standard excavation process (S2), and the excavation by the cutter head 120 is impossible due to the collapse of the face (S3), the tunnel excavation by the cutter head 120 is performed. Is interrupted (see FIG. 10), and the process proceeds to tunnel excavation (auxiliary excavation process) using the excavator 200 (S4).
Then, when the defective ground is broken through the tunnel excavation in the auxiliary excavation process (S5), the cutter excavation 120 returns to the standard excavation process for tunnel excavation (S6).
Next, the tunnel excavation (auxiliary excavation process) using the excavator 200 will be described with reference to the flowcharts of FIGS. 11 and 12 and the process explanatory diagrams of FIGS. 13 to 24.
Note that the flowchart of FIG. 11 shows each step included in the auxiliary excavation step, and the flowchart of FIG. 12 shows each step included in the preparation step which is one of the steps included in the auxiliary excavation step.

In carrying out the tunnel excavation using the excavator 200, first, a ground improvement by injecting a chemical solution is performed (ground improvement step, chemical injection step: S10 in FIG. 11, see FIG. 13). Control the collapse.
In the ground improvement by injecting chemicals, a boring machine 280 is installed in the body 110, and a boring hole extending obliquely from the ceiling part of the mine wall 150 around the body 110 toward the face of the face is provided by the boring machine 280. A plurality of holes are drilled, and a chemical solution such as a urethane-based injection material is injected into each of the drilled bore holes, and the ground level is improved by consolidating the chemical solution (see FIG. 20).
The ground improvement by injecting the drug is a process that should be performed as necessary and can be omitted.

When the ground improvement by chemical injection is performed, the rear body 112b of the two bodies 112a and 112b forming the rear body 112 is fixed to the ground by the anchor 282 or the like, and the concrete spraying is completed. The body 112b is held at a position on the front side of the wall 150, and the connecting pin 283 connecting the bodies 112a and 112b is removed so that the body 112a fitted on the body 112b can move rearward. (Retreat preparation step: S20 of FIG. 11, see FIG. 14).
Then, while the gripper 132 is pressed against the pit wall, the thrust jack 140 is contracted to retract the cutter head 120 from the excavation surface by the cutter head 120 by a predetermined distance (retracting step: S30 in FIG. 11, (See FIG. 15), a space for pushing and opening the opening / closing door 123 is secured in front of the cutter head 120.
When the thrust jack 140 is pressed directly against the lining body composed of segments or the like to obtain a propulsion reaction force, the thrust jack 140 is contracted to move the cutter head 120 from the excavated surface by the cutter head 120 at a predetermined distance. Just retreat.

The predetermined distance for retracting the cutter head 120 is a distance that can secure a space for pushing the opening / closing door 123 forward, and the size of the opening / closing door 123, the fully open opening degree of the opening / closing door 123, and the opening / closing door 123. Set to an appropriate value that differs depending on various conditions such as the structure for fixing the state. In this embodiment, as one mode, the predetermined distance is set to about 1.5 m.
When the thrust jack 140 is in a contracted state and cannot be further contracted, the gripper 132 is separated from the pit wall, the thrust jack 140 is extended to push the gripper 132 rearward, and then the gripper 132 is moved to the pit wall. Again, the gripper 132 contracts the thrust jack 140 while obtaining a reaction force, so that the cutter head 120 retracts the excavation surface by a predetermined distance.
When a thrust reaction force is obtained by directly pressing the thrust jack 140 against the lining body composed of segments or the like, the thrust jack 140 is extended after releasing the pressing force against the lining body and separating them. Again, the thrust jack is pressed against the lining body at another location to contract the thrust jack, thereby retracting the cutter head 120 by a predetermined distance from the excavated surface by the cutter head 120.

After releasing the connection between the body 112a (front body) and the body 112b (rear body), the body 112a retracts integrally with the cutter head 120, while the body 112b is fixed to the ground by the anchor 282. The position when the tunnel excavation by the cutter head 120 is interrupted is maintained. The cutter head 120 and the body 112a can be integrally retracted without fixing the body 112b to the ground.
Further, when the cutter head 120 is retracted, the cutter head 120 is rotated so that the face plate 127a is on the upper side, the central face plate 127a of the face plates 127a-127c is removed, and the face plate 127a is removed from the opening opened. While the concrete is sprayed on the mine wall 150, the cutter head 120 is retracted (ground improvement process, spraying process: S30 in FIG. 11, see FIG. 15) to suppress the collapse of the mine wall 150 due to the retreat.

In concrete spraying when the cutter head 120 is retracted, the worker 320 holds the spray nozzle 321 and sprays concrete toward the mine wall 150 from the opening opened by removing the face plate 127a (ground improvement step, Spraying process: S30 of FIG. 11, see FIG. 15). In the spraying step, instead of spraying concrete, mortar, cement-based solidifying material, or the like can be sprayed, which results in tunnel support work.
When the cutter head 120 is retracted to a predetermined position, preparatory work for starting excavation by the excavator 200 (auxiliary excavation preparation step: S40 in FIG. 11, S41 to S45 in FIG. 12) is performed.

Hereinafter, the auxiliary excavation preparation step will be described in detail with reference to the flowchart of FIG.
As the preparatory work (auxiliary excavation preparation step), first, the cutter head 120 is rotated to change the attachment position of the face plate 127a from the upper side to the lower side (rotation step: S41 of FIG. 12, see FIG. 16). Then, the hopper chute 170 and the like, which hinder the movement of the excavator 200, are removed (removal step: S42 in FIG. 12, see FIG. 16).

Further, as the preparatory work (auxiliary excavation preparation step), the opening / closing door 123 closing the central opening 123a of the cutter head 120 is pushed open from the inside of the TBM 100 (opening step: S43 in FIG. 12, see FIG. 16).
Here, the opening / closing door 123 can be configured to be opened rearward, but if the configuration is such that the opening / closing door 123 is pushed and opened toward the face of the face, the cutter is used when excavating by the excavator 200. A wide space can be secured in the body in front of the head 120, and the arm of the excavator 200 can be easily ejected from the opening 123a.
If the cutter head 120 is provided with an openable and closable opening so that the cutter head 120 can be opened rearward, the cutter head 120 can be pulled out from the opened opening without retracting the cutter head 120 when a bad ground is encountered. It is possible to visually check the condition of the ground in front of 120.

The operation of pushing open the opening / closing door 123 can be performed by combining the movement of the clamp box 210 of the excavator 200 and the extension of the boom 230 by the sliding jack 223.
That is, the bucket 240 and the back side of the opening / closing door 123 are connected by a connecting material, and the sliding jack 223 is extended while the clamp box 210 is clamped by the rail 135, so that the opening / closing door 123 is directed toward the front of the cutter head 120. The cutter head 120 and the opening / closing door 123 are connected by a fixing member having a ratchet structure to hold the push-open position.
When the sliding jack 223 is fully extended, the sliding jack 223 is contracted, the position of the clamp box 210 is changed to a position further forward and the clamping is performed again, and the sliding jack 223 is extended. By repeatedly expanding and contracting the sliding jack 223 and changing the position of the clamp box 210, the open / close door 123 is pushed to the fully open position.

  Further, as the preparatory work (auxiliary excavation preparation process), two face plates 127b and 127c except for the face plate 127a which has been detached and which has already been removed are detached, and jacks (not shown) are carried out. ) Is used to push the soil discharging conveyor 180 to the vicinity of the scraper 121b1 (conveyor transfer step: S45 in FIG. 12, see FIG. 16), and the extension rail 138 is attached to the end of the rail 135 on the cutter head 120 side. Is performed (rail joining step: S46 in FIG. 12, see FIG. 16).

When the preparatory work (auxiliary excavation preparation step: S40 in FIG. 11, S41 to S45 in FIG. 12) is completed, the clamp box 210 of the excavator 200 is unclamped, the front wheels 211 are rotationally driven, and the opening / closing door 123 is opened. The support frame 220 and the boom 230 are inserted into the opening 123a opened and opened, and the clamp box 210 is advanced to a position where the work for discharging the soil (sludge) under the cutter head 120 by the bucket 240 can be performed (excavator advancement). Process: S50 of FIG. 11, see FIG. 17).
Then, by raising and lowering the arm of the excavator 200 and turning the arm, and by tilting the bucket 240, the bucket 240 puts the soil (sludge) under the cutter head 120 on the earth discharging conveyor 180 and carries it out backward (extract). Sludge discharge step by cab: S60 of FIG. 11, see FIG. 17).

  After discharging the earth and sand using the excavator 200, the excavator 200 and the earth discharging conveyor 180 are once retracted, and the earth and sand (sludge) below the cutter head 120 that cannot be completely removed by the discharging operation by the bucket 240 is removed. A manual removing operation is carried out (manual slipping process: S60 in FIG. 11, refer to FIG. 18) to secure an installation space for the skirt portion 181 attached to the tip of the earth discharging conveyor 180. In other words, the earth and sand remaining at the planned installation location of the skirt portion 181 is manually removed so that the skirt portion 181 can be installed on the tip of the earth discharging conveyor 180.

The skirt portion 181 attached to the tip of the earth discharging conveyor 180 is a member for guiding the earth and sand in the front lower part of the cutter head 120 onto the conveying surface of the earth discharging conveyor 180, and is located below the conveying surface of the tip of the earth discharging conveyor 180. Form an inclined surface that spreads toward the mine wall.
When the excavator 200 performs tunnel excavation, the sand excavated by the bucket 240 can be pushed up by the bucket 240 onto the skirt portion 181 and placed on the conveying surface of the earth discharging conveyor 180. To facilitate the earth removal work used.

When the earth and sand in the front lower part of the cutter head 120 are removed and the installation space for the skirt portion 181 is secured, the scraper 121b1 is removed to open the entire area of the opening 128 (skirt portion disposition preparation step: S70 in FIG. 11, FIG. 19, see FIG. 20), and then attach the skirt portion 181 to the tip of the soil discharging conveyor 180 (skirt portion providing step: S80 in FIG. 11, see FIG. 19).
Then, by pushing again the earth discharging conveyor 180 having the skirt portion 181 attached to the tip thereof, the tip of the earth discharging conveyor 180 is inserted into the opening 128 opened by the removal of the face plates 127a to 127c, and the front of the cutter head 120 is inserted. So that the lower end of the skirt portion 181 is close to or pressed against the pit wall 150 (skirt portion arranging step, conveyor moving step: S80 in FIG. 11, see FIG. 19).

When the work of projecting the soil discharging conveyor 180 to which the skirt portion 181 is attached to the front of the cutter head 120 is completed, the clamp box 210 is then advanced to the tunnel excavation position so that the excavator 200 can perform tunnel excavation ( Forward step: S90 of FIG. 11, see FIG. 21). The tunnel excavation position of the clamp box 210 is, for example, a position where the front end of the clamp box 210 is near the opening 123a of the cutter head 120.
That is, when encountering a poor ground (soft ground) where it is difficult to excavate the entire cross section by the cutter head 120, and when switching from excavation by the cutter head 120 to excavation by the excavator 200, the cutter head 120 is retreated to move the cutter head 120. The opening / closing door 123 is pushed open toward the face of the face, and then the clamp box 210 is moved forward along the main beam 130 so that the support position of the excavator 200 with respect to the main beam 130 is closer to the cutter head 120 from the retracted position. The arm body (support frame 220 and boom 230) of the excavator 200 is projected to the front of the cutter head 120 through the opening 123a opened by opening and closing the opening / closing door 123 after moving to the tunnel excavation position.
When the clamp box 210 is clamped at the tunnel excavation position, the bucket 240 excavates the ground in front of the cutter head 120, and the excavated earth and sand is pushed up by the bucket 240 to the conveying surface of the earth discharging conveyor 180 via the skirt portion 181. The work of discharging the rearward is performed (excavation step: S100 of FIG. 11, refer to FIG. 21), the sliding jack 223 is extended to the maximum extent, and the ground within a range reached by the bucket 240 is excavated.
As described above, when encountering a bad ground (soft ground) where it is difficult to excavate the entire cross section by the cutter head 120, the opening / closing door 123 provided on the cutter head 120 is opened to move the arm of the excavator 200 to the cutter head. Since the auxiliary excavator 200 is projected to the front of 120 to perform the auxiliary excavation by the excavator 200, the excavator 200 and the excavator 200 can be easily (in a short time) changed to efficiently and efficiently. You can break through.

Here, in the excavation work by the excavator 200 (bucket 240), the diameter of the excavation shaft is equal to the diameter of the excavation shaft by the cutter head 120, and preferably the diameter is larger than the diameter of the excavation shaft (excavation step: FIG. 11 S100, see FIG. 22). As a result, when the TBM 100 is propelled into the tunnel driven by the excavator 200, it is possible to prevent the TBM 100 from being caught on the mine wall 150 and being unable to propel the tunnel.
When excavation and soil removal are completed with the sliding jack 223 extended to a predetermined maximum length and further excavation cannot be performed (see S110 in FIG. 11), the gripper 132 is pressed against the pit wall. By extending the thrust jack 140 with, the cutter head 120 is propelled together with the excavator 200 by the distance retracted when the excavator 200 excavates from the excavator 200 (propulsion step: in FIG. 11). S120, see FIG. 23).

In the first propulsion work in excavation by the excavator 200, the body 112b holds the fixed position with respect to the natural ground by the anchor 282, and the front body 112a externally fitted to the body 112b advances together with the cutter head 120. However, the bodies 112a and 112b return to the relative positional relationship before the retreat.
When the relative positional relationship between the bodies 112a and 112b returns to the state before the retreat, the connection pin 283 that connects the bodies 112a and 112b is attached (see FIG. 23) to allow the bodies 112a and 112b to move integrally. Further, the anchors 282 that have fixed the body 112b to the ground are removed so that the bodies 112a and 112b can be integrally advanced.

After that, the excavation by the bucket 240 is restarted, and when the excavation with the sliding jack 223 extended to a predetermined maximum length is completed, the TBM 100 is propelled by the refilling of the gripper device 133 and the extension of the thrust jack 140.
In this way, as a process for breaking through the poor ground, it includes excavation by the bucket 240 (excavation process) and propulsion of the TBM 100 (propulsion process), and the excavation process by the bucket 240 and the propulsion process of the TBM 100 are repeated. Dig into the tunnel.

That is, in the auxiliary excavation process by the excavator 200, the bucket 240 is projected to the front of the cutter head 120 to excavate the ground, and the excavation of the bucket 240 by the operation of the turning jack 221, the depression jack 222 and the sliding jack 223. When the (digging step) is completed, the thrust jack 140 is extended to integrally propel the cutter head 120, the excavator 200, and the main beam 130 forward (propelling step), and the bucket 240 is again drilled (digging step). Then, the excavation process using the bucket 240 and the propulsion process of the TBM 100 are repeated to advance the tunnel.
When the thrust jack 140 is fully extended in the propulsion process in the auxiliary excavation process by the excavator 200, the gripper 132 is moved to a side closer to the face of the gripper 132, and the excavator 200 is moved. In other words, the TBM 100 can be propelled further forward. As described above, the propulsion process in the auxiliary excavation process has a configuration in which the extension and contraction of the thrust jack 140 and the gripper rearrangement are repeated, and is performed in the same manner as the propulsion process in the standard excavation process by the cutter head 120.
When the thrust jack 140 is directly pressed against the lining body composed of segments or the like to obtain a propulsive reaction force, the thrust jack 140 is extended and contracted, and the position (position) of the lining body against which the thrust jack 140 is pressed is changed. By repeating the rearrangement, the TBM 100 can be propelled forward.

  When the thrust jack 140 is expanded and contracted in a state where the clamp box 210 is fixed on the rail 135 integrally provided on the main beam 130, the excavator 200 causes the mine wall against which the gripper 132 is pressed to be the reference position. It moves in the front-rear direction together with the main beam 130 (cutter head 120). Further, when the sliding jack 223 is expanded and contracted, the bucket 240 moves in the front-rear direction based on the position on the rail 135 to which the clamp box 210 is fixed. That is, with the clamp box 210 fixed on the rail 135, the bucket 240 can move in the front-rear direction according to the expansion and contraction of the sliding jack 223 and the thrust jack 140. In other words, the bucket 240 slides. The movable jack 223 and the thrust jack 140 can move forward and backward with respect to the natural ground according to expansion and contraction.

When excavating a bad ground with the bucket 240, a part (opening 128) of the cutter head 120 of the TBM 100 is open, but the remaining part is covered by the cutter head 120, so Even if the mountain collapses, the safety inside the TBM 100 can be secured. Further, even if there is a long section of bad ground, the tunnel can be continuously excavated by repeating the excavation process and the propulsion process, so that the process can be shortened.
Then, the excavation process using the bucket 240 and the propulsion process of the TBM 100 are repeated until the defective ground is broken through (S130 → S90 in FIG. 11), and after the defective ground is broken, the excavator 200 and the earth discharging conveyor are repeated. 180 is retracted, the face plates 127a-127c are attached to the cutter head 120, and the opening / closing door 123 is further closed to change the configuration of the TBM 100 from the excavator 200 excavation work state (auxiliary excavation process) to the cutter head 120 excavation work. The state is returned to and the excavation by the cutter head 120 (standard excavation process) is restarted (S5 → S6 in FIG. 9, S130 → end in FIG. 11).
Note that when the excavation process using the bucket 240 and the propulsion process of the TBM 100 are repeated, another process such as a ground improvement process can be performed between the excavation process and the propulsion process.

During the process of excavation by the excavator 200 (excavation process: S100 in FIG. 11), when it is necessary to spray concrete on the excavation surface to improve the ground, spraying concrete using the excavator 200 (spraying process) Can be done.
In this way, it is possible to perform support work such as concrete spraying during excavation by the excavator 200 or in front of the cutter head 120, and such support work prevents further collapse of bad ground. be able to.
FIG. 24 shows one mode of a configuration for performing concrete spraying using the excavator 200.

The spraying machine 292 shown in FIG. 24 includes a spraying nozzle 290 and a spraying angle changing mechanism 291, and the spraying nozzle 290 is attached to the bucket 240 via the spraying angle changing mechanism 291 (a spraying nozzle attaching step). Then, by changing the direction of the spray nozzle 290 by the spray angle changing mechanism 291, and by ascending and descending motions and swiveling motions of the support frame 220, the spraying is performed on the entire area where the spraying of concrete is required (spraying process). Is configured so that
The spray angle changing mechanism 291 includes a rotation shaft 291a, a holder member 291b supported at the tip of the rotation shaft 291a so as to be swingable around a swing shaft PS orthogonal to the rotation shaft 291a, and a main body portion that rotatably supports the rotation shaft 291a. 291c, etc. are included.

The main body 291c is attached to the bucket 240 such that the axis of the rotating shaft 291a is substantially parallel to the axis of the support frame 220, and the spray nozzle 290 swings the axis of the spray nozzle 290 relative to the holder member 291b. It is attached so that the radial direction parallel to the moving plane and extending from the side close to the swing axis to the side far from the swing axis is the blowing direction.
The swing angle of the holder member 291b is, for example, an angular position where the axial direction of the rotary shaft 291a and the axial line of the spray nozzle 290 are substantially parallel, and the axial direction of the rotary shaft 291a and the axial line of the spray nozzle 290 are substantially equal to each other. It is set to an angle between the orthogonal angular positions. However, the swing angle of the holder member 291b is not limited to the above setting and can be set arbitrarily.

Here, the swinging of the holder member 291b, the rotation of the rotary shaft 291a, and the ascending / descending motion and the swiveling motion of the support frame 220 can be performed in combination to spray concrete on the excavation surface.
Note that, in the structure shown in FIG. 24, the spray nozzle 290 is attached to the bucket 240 via the spray angle changing mechanism 291, but the spray nozzle 290 may be directly attached to the bucket 240. When the spray nozzle 290 is directly attached to the bucket 240, a mechanism for displacing the bucket 240 including the rotating mechanism functions as a spray angle changing mechanism by providing a rotating mechanism for the bucket 240, for example.

Although the contents of the present invention have been specifically described with reference to the preferred embodiments, it is obvious that those skilled in the art can adopt various modifications based on the basic technical idea and teaching of the present invention. is there.
The working device attached to the tip of the boom 230 is not limited to the bucket 240, and an impact device such as a hydraulic breaker can be used.

  Further, the opening 123a of the cutter head 120 through which the arm of the excavator 200 is inserted can be opened by removing the face plate, and the face plates 127a-127c can be formed into an openable / closable door. Further, the opening for protruding the support frame 220 to the cutting face and the opening for protruding the earth discharging conveyor 180 to the cutting face can be opened by one opening / closing door (or face plate). .

In addition, the TBM 100 can include a dedicated jack for opening and closing the opening / closing door 123.
Further, the opening for projecting the arm of the TBM 100 to the cutting face and the opening for projecting the soil discharging conveyor 180 to the cutting face can be mutually independent openings partitioned by the crosspiece.

In addition to the gripper device (rear gripper) 130 arranged behind the body 110, a gripper device (front gripper) may be provided on the front side of the body 110.
Further, when excavating by the excavator 200, a conveyor unit is added to the face end of the soil discharging conveyor 180 used at the time of excavating by the cutter head 120, and the added conveyor unit protrudes from the cutter head 120 toward the face. Can be configured as follows.

Further, a camera for photographing the face of the face is installed at a corner of the opening 123a opened by opening the opening / closing door 123, and the image captured by the camera is displayed on a liquid crystal screen or the like to operate the excavator 200. A stereo camera can be set as a camera to convert a construction site into three-dimensional data.
Further, in the above-described embodiment, when the excavator 200 is used for excavation, the extension rail 138 is added to the end of the rail 135 on the cutter head 120 side. However, instead of adding the extension rail 138, The rail 135 may be moved to the face of the face (the side of the cutter head 120) within the 110.
The claims at the beginning of the application were as follows.
[Claim 1]
A method of excavating a tunnel by a tunnel excavator, in which a cutter head is rotatably mounted on a front portion of a body, and a reaction force for propelling from a pit wall or a lining body is obtained.
An auxiliary excavator for excavating by a working device at the tip of an arm is installed in the body, and an opening that can be opened and closed is provided in the cutter head.
A tunnel excavation method including an auxiliary excavation step of projecting the arm body forward from the opened opening and excavating the ground by the working device to advance a tunnel.
[Claim 2]
The auxiliary excavation step,
An excavation step of excavating the natural ground by the working device,
A propulsion step of propelling the tunnel excavator,
The tunnel excavation method according to claim 1, further comprising:
[Claim 3]
The opening from which the arm is projected is configured to be openable and closable by an opening / closing door that is pushed open toward the front of the cutter head,
The tunnel excavation method according to claim 1 or 2, wherein the auxiliary excavation step includes an opening step of pushing and opening the opening / closing door toward the front of the cutter head.
[Claim 4]
The auxiliary excavation step further includes a retreat step of retracting the tunnel excavator,
The tunnel excavation method according to claim 3, wherein in the opening step, the opening / closing door is pushed open toward the front of the cutter head after the tunnel excavator is retracted.
[Claim 5]
The tunnel excavator includes an earth discharging conveyor,
The auxiliary excavation step includes a conveyor transfer step of inserting the tip of the soil discharging conveyor through the opened opening and projecting the conveyor head to the lower front portion of the cutter head. The tunnel excavation method described.
[Claim 6]
The conveyor relocating step includes a skirt portion arranging step of arranging a skirt portion for guiding the earth and sand in the front lower part of the cutter head on the conveying surface of the earth discharging conveyor protruding in front of the cutter head. 5. The tunnel excavation method described in 5.
[Claim 7]
The auxiliary excavation step,
A spray nozzle mounting step of mounting a spray nozzle to the working device of the auxiliary excavator,
A spraying step of spraying concrete or mortar onto the excavation surface from the spray nozzle by projecting the arm body forward from the opened opening,
The tunnel excavation method according to claim 1, further comprising:
[Claim 8]
A cutter excavator in which a cutter head is rotatably mounted on a front portion of a body and obtains a reaction force for propelling from a pit wall or a lining body,
An auxiliary excavator for excavating by a working device at the tip of an arm is arranged in the body, and an opening that can be opened and closed is provided in the cutter head.
A tunnel excavator configured such that the arm body is protruded forward from the opened opening to excavate the ground by the working device to perform tunnel excavation.

  100 ... TBM (tunnel boring machine, tunnel excavator), 110 ... Body, 120 ... Cutter head, 122 ... Cutter head drive motor, 123 ... Opening door, 123a ... Opening part, 128 ... Opening part, 130 ... Main beam, 132 ... Gripper, 133 ... Gripper device, 135 ... Rail, 140 ... Thrust jack, 180 ... Soil conveyor, 181, ... Skirt part, 200 ... Excavator (auxiliary excavator), 210 ... Clamp box, 220 ... Support frame (arm) Body), 230 ... Boom (arm body), 240 ... Bucket (working device), 292 ... Spraying machine

Claims (10)

A method of excavating a tunnel by a tunnel excavator, in which a cutter head is rotatably mounted on a front portion of a body, and a reaction force for propelling from a pit wall or a lining body is obtained.
An auxiliary excavator for excavating by a working device at the tip of an arm is installed in the body, and an opening that can be opened and closed is provided in the cutter head.
Said arms from said opening which has opened by drilling natural ground by the working device protrudes forward looking contains an auxiliary excavation process of excavating the tunnel,
The opening from which the arm is projected is configured to be openable and closable by an opening / closing door that is pushed open toward the front of the cutter head,
The auxiliary excavation step is a tunnel excavation method including an opening step of pushing and opening the opening / closing door toward the front of the cutter head . The auxiliary excavation step further includes a retreat step of retracting the tunnel excavator,
The tunnel excavation method according to claim 1, wherein in the opening step, the opening / closing door is pushed open toward the front of the cutter head after the tunnel excavator is retracted. The auxiliary excavation step,
An excavation step of excavating the natural ground by the working device,
A propulsion step of propelling the tunnel excavator,
The tunnel excavation method according to claim 1 or 2, further comprising: A method of excavating a tunnel by a tunnel excavator, in which a cutter head is rotatably mounted on a front portion of a body, and a reaction force for propelling from a pit wall or a lining body is obtained.
An auxiliary excavator for excavating by a working device at the tip of an arm is installed in the body, and an opening that can be opened and closed is provided in the cutter head.
Said arms from said opening which has opened by drilling natural ground by the working device protrudes forward looking contains an auxiliary excavation process of excavating the tunnel,
The opening is configured to be opened and closed by an opening and closing door,
The auxiliary excavation step,
A retracting step of retracting the tunnel excavator,
An opening step of opening the opening and closing door after the retreating step,
Tunnel excavation method including . The auxiliary excavation step,
A forward step of protruding the arm body forward from the opening after the opening step,
An excavation step of excavating a natural rock by the working device after the advance step ,
A propulsion step of propelling the tunnel excavator after the excavation step ,
The tunnel excavation method according to claim 4 , further comprising: The tunnel excavator includes an earth discharging conveyor,
The auxiliary excavation process, the opened said opening is inserted the tip of the dumping conveyor further comprises a conveyor transfer step of projecting front lower portion of the cutter head, any one of claims 1 to 5 Tunnel excavation method described in. The conveyor transfer step includes a skirt portion disposed step of disposing the skirt portion for guiding the front bottom sediment of the cutter head on the conveying surface of the soil discharge conveyor to protrude in front of the cutter head, claim 6. The tunnel excavation method according to item 6 . The auxiliary excavation step,
A spray nozzle mounting step of mounting a spray nozzle to the working device of the auxiliary excavator,
A spraying step of spraying concrete or mortar onto the excavation surface from the spray nozzle by projecting the arm body forward from the opened opening,
The tunnel excavation method according to any one of claims 1 to 7 , further comprising: A cutter excavator in which a cutter head is rotatably mounted on a front portion of a body and obtains a reaction force for propelling from a pit wall or a lining body,
An auxiliary excavator for excavating by a working device at the tip of an arm is arranged in the body, and an opening that can be opened and closed is provided in the cutter head.
In the tunnel excavator, which is configured to perform forward tunnel excavation by excavating the ground by the working device by protruding the arm body forward from the opened opening ,
The tunnel excavator, wherein the opening from which the arm is projected is configured to be openable / closable by an opening / closing door pushed forward toward the front of the cutter head . The tunnel excavator according to claim 9, wherein a spray nozzle for spraying concrete or mortar onto the excavation surface is attached to the working device.