JP2016151170A - Tunnel excavator and tunnel construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel excavator and a tunnel excavation method that facilitate excavation work when excavating a preceding tunnel in a defective ground, while suppressing increase in machine body length.SOLUTION: A tunnel excavator includes: a cutter head 12 supported rotatably on a front part of an excavator body 11, for excavating a pit face in a ground; a bulk head 20 having a chamber 27 for storing excavation sediment generated as the cutter head 12 excavates the ground, formed between the cutter head 12 and the bulk head; a cutter-side opening 34 formed on the cutter head 12; a cutter-side door 35 that opens/closes the cutter-side opening 34; a partition wall-side opening 21 formed in the bulk head 20; and a partition wall-side door 28 that opens/closes the partition wall-side opening 21. When excavating a preceding tunnel Ta from inside the excavator body 11 into a pit face that opens in front through the opened partition wall-side opening 28 and the cutter-side opening 35, the fully opened cutter-side door 35 is brought into contact with the fully opened partition wall-side door 28.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a tunnel excavator and a tunnel construction method capable of continuously constructing a tunnel along a preceding tunnel excavated in the defective ground even when the excavated ground is changed to a defective ground such as a crushing zone.

  2. Description of the Related Art Conventionally, tunnel boring machines have been provided as tunnel excavating machines in which excavated ground is hard ground such as rock. However, some excavated grounds include a mixture of a plurality of types of soils having different soil properties, and when excavating a tunnel with a tunnel boring machine, a poor ground such as a crush zone may be encountered.

  Thus, when a tunnel boring machine encounters a bad ground, the airframe is restrained by the collapse of the face and the displacement of the surrounding ground, and the frictional force against the propulsion reaction force increases. As a result, the tunnel boring machine may not be able to dig.

  Therefore, when the tunnel boring machine encounters a bad ground, the excavation is temporarily stopped, the chemical solution is injected in front of the face, the ground is improved, and people and heavy equipment are used to make the tunnel boring machine. The preceding preceding tunnel was excavated until the bad ground was finished.

  Such a conventional tunnel boring machine is disclosed in Patent Document 1, for example.

JP 2002-364284 A

  Here, the conventional tunnel boring machine is a so-called open-type tunnel boring machine in which excavated earth and sand generated by excavating a self-supporting ground is dug without filling the chamber, and the opening on the cutter side A cutter side opening / closing door for opening and closing the part, and a partition side opening / closing door for opening and closing the partition side opening. And when a bad ground is encountered, the cutter side opening / closing door and the partition side opening / closing door are rotated toward the rear of the tunnel to open the cutter side opening and the partition side opening, and then the cutter side opening is opened. The leading tunnel is excavated while improving the ground through the part and the partition side opening.

  However, when the cutter side opening / closing door and the partition side opening / closing door are rotated, the cutter side opening / closing door and the partition side opening / closing door after the rotation occupy the interior space. Thereby, depending on those positional relationships, the excavation work of the preceding tunnel is adversely affected.

  Therefore, as a means for solving such a problem, it is conceivable to increase the amount of rotation of the cutter side opening / closing door and the partition side opening / closing door. In order to avoid contact between the side opening / closing door and the partition wall, it is necessary to largely retreat the installation position of the partition wall toward the rear of the tunnel. That is, the length of the chamber for accumulating excavated earth and sand is increased by the amount of the installation position of the bulkhead to the rear of the tunnel, and as a result, the length of the tunnel boring machine is increased.

  Accordingly, the present invention solves the above-described problem, and provides a tunnel excavator and a tunnel construction method capable of easily performing excavation work when excavating a preceding tunnel to a defective ground while suppressing the length of the aircraft. The purpose is to do.

The tunnel excavator according to the first invention for solving the above-described problems is
A cutter head supported rotatably at the front of the excavator body, and excavating a face on the ground;
A partition wall provided in the excavator body, and forming a chamber between the cutter head and a chamber for storing excavated earth and sand generated by excavation of the cutter head;
A cutter-side opening that is formed in the cutter head and communicates between the face and the chamber;
A cutter-side opening / closing door that opens the cutter-side opening by rotating the upper end toward the rear of the tunnel with the lower end as a rotation center;
A partition-side opening formed in the partition and communicating with the inside of the chamber;
A partition side opening / closing door that opens the partition side opening by rotating the upper end toward the rear of the tunnel with the lower end as a rotation center,
When the leading tunnel can be excavated from the inside of the excavator body with respect to the cut face opened forward through the opened cutter side opening and the bulkhead side opening, the fully opened cutter side opening / closing door is fully opened. It is in contact with at least one of the partition-side opening / closing door and the opened partition-side opening.

The tunnel excavator according to the second invention for solving the above-mentioned problems is
It is connected to the partition-side opening / closing door that is fully opened, and is provided with a traveling platform on which a heavy machine for excavating the preceding tunnel can travel.

A tunnel excavator according to a third invention for solving the above-described problem is
A screw conveyor that discharges the excavated sediment stored in the chamber toward the rear of the tunnel of the excavator body;
The screw conveyor can be bent in the vertical direction and the horizontal direction of the tunnel.

A tunnel excavator according to a fourth invention for solving the above-described problem is
On the rear surface of the partition side opening / closing door,
A drilling machine that drills a boring hole in front of the face,
A chemical solution injection machine for injecting a chemical solution into the boring hole drilled by the hole drilling machine and hardening the ground in front of the face is detachably provided.

The tunnel construction method according to the fifth invention for solving the above problem is as follows.
The cutter head and the partition wall provided in the excavator body are configured to remove excavated earth and sand generated by excavating the face while excavating the face on the ground by the rotation of the cutter head provided at the front of the excavator body In a tunnel construction method in which a tunnel is dug by taking it into a chamber formed between and discharging it to the rear of the excavator body,
During excavation of the tunnel, when it changes to bad ground, the excavation is paused,
Bending the screw conveyor that discharges the excavated soil
The cutter side opening / closing door is rotated toward the rear of the tunnel to open the cutter side opening formed in the cutter head, and the partition side opening / closing door is rotated toward the rear of the tunnel to form the partition. Open the partition wall side opening,
The fully opened cutter-side opening / closing door is brought into contact with at least one of the fully-opened partition-side opening / closing door and the opened partition-side opening,
A preceding tunnel is excavated from within the excavator body with respect to the face opened forward through the opened cutter side opening and the partition side opening.

  Therefore, according to the tunnel excavator and the tunnel construction method according to the present invention, the heavy machinery can be used without disassembling without changing the position of the partition wall in the longitudinal direction of the tunnel and the length of the chamber in the longitudinal direction of the tunnel. . Therefore, it is possible to easily perform excavation work when excavating the preceding tunnel to the bad ground while suppressing the length of the aircraft.

1 is a longitudinal sectional view of a tunnel excavator according to a first embodiment of the present invention. 1 is a front view of a tunnel excavator according to a first embodiment of the present invention. It is the longitudinal cross-sectional view which showed the mode when excavating a preceding tunnel. FIG. 4 is a front view of FIG. 3. It is a longitudinal cross-sectional view of the tunnel excavator based on 2nd Example of this invention. It is a front view of the tunnel excavator which concerns on 2nd Example of this invention. It is AA arrow sectional drawing of FIG. FIG. 6 is a view taken in the direction of arrow B in FIG. 5.

  Hereinafter, a tunnel excavator and a tunnel construction method according to the present invention will be described in detail with reference to the drawings.

  As shown in FIGS. 1 and 2, a tunnel excavator 1 is a sealed tunnel boring machine for excavating a tunnel T in earth and sand ground or hard ground Ga, for example, and has a cylindrical excavator body (skin Plate) 11 and a cutter head 12 having a disk shape.

  A bulkhead 20 serving as a partition wall is provided in the front end portion of the excavator body 11, and a ring-shaped rotating body 22 is rotatably supported on the bulkhead 20. A plurality of connecting arms 23 are supported on the front portion of the rotating body 22 along the circumferential direction of the rotating body 22, and the cutter head 12 is connected to the front ends of these connecting arms 23. Yes. On the other hand, a ring gear 24 having a ring shape is provided at the rear portion of the rotating body 22 coaxially with the rotating body 22.

  The bulk head 20 is provided with a plurality of cutter turning motors 25 along the circumferential direction of the excavator body 11. A drive gear 26 is mounted on the output shaft of each cutter turning motor 25, and these drive gears 26 mesh with the ring gear 24.

  On the other hand, a cutter head 12 is provided at the front portion of the excavator body 11, and a large number of disc cutters 31 and cutter bits 32 are detachably attached to the front surface portion of the cutter head 12. Yes. A plurality of excavated earth and sand intakes 33 are formed around the disc cutter 31 and the cutter bit 32 in the cutter head 12 along the radial direction of the cutter head 12.

  Accordingly, by driving the cutter turning motor 25, the rotation of the drive gear 26 can be transmitted from the ring gear 24 to the rotating body 22, and therefore the cutter head 12 can be rotated. As a result, the face can be excavated on the ground by the disc cutter 31 and the cutter bit 32 swiveled around the rotation axis of the cutter head 12.

  Further, a chamber 27 is defined between the cutter head 12 and the bulk head 20. The chamber 27 is a space (chamber) for temporarily storing excavated earth and sand. In the chamber 27, excavated earth and sand generated by ground excavation of the disc cutter 31 and the cutter bit 32 are removed. It is adapted to be taken in via the excavated earth and sand intake 33 of the head 12. A soil pressure gauge 55 is provided on the rear surface of the bulkhead 20. The earth pressure gauge 55 can measure the pressure (earth pressure) of the excavated earth and sand in the chamber 27.

  And in the excavator main body 11, the screw conveyor 41 is provided so that it may incline upwards as it goes to a rear end from a front end. At this time, the front end opening of the screw conveyor 41 passes through the lower part of the bulkhead 20 and is inserted into the chamber 27. Here, the screw conveyor 41 is a folding type screw conveyor, and can be bent in the tunnel vertical direction and the tunnel horizontal direction (tunnel width direction) with the folding mechanisms 41a and 41b on the front end side as a base point ( Swingable). Therefore, by rotating the screw conveyor 41, the excavated earth and sand accumulated in the chamber 27 can be discharged toward the rear of the excavator body 11.

  Further, in the rear end portion of the excavator body 11, an erector device 42 is supported so as to be movable in the tunnel front-rear direction, the tunnel radial direction, and the tunnel circumferential direction. This erector device 42 assembles the segment S as a lining member along the inner wall surface (tunnel wall) of the tunnel T, and the segment S follows the inner wall surface shape of the excavated tunnel T. It has become a ring piece. Therefore, the plurality of segments S can be assembled in a ring shape along the circumferential direction of the tunnel by driving the erector device 42.

  Further, a plurality of shield jacks (propulsion jacks) 43 are supported on the inner peripheral surface of the excavator body 11 along the circumferential direction of the inner peripheral surface. A spreader 43a is attached to the rod tip of each shield jack 43, and this spreader 43a faces the front end surface of the existing segment S in the tunnel longitudinal direction.

  Accordingly, the excavating reaction force (propulsion reaction force) can be applied to the excavator body 11 by extending the shield jack 43 toward the rear of the tunnel and pressing the spreader 43a against the front end surface of the existing segment S. Thereby, the excavator body 11 can be advanced by the excavation reaction force generated when the shield jack 43 presses the segment S.

  A plurality of tail packings (sealing seals) 44 are provided on the inner peripheral surface of the rear end portion of the excavator main body 11 in the longitudinal direction of the tunnel. The tail packing 44 is provided over the entire circumferential direction on the inner peripheral surface of the excavator body 11 and is in close contact with the outer peripheral surface of the existing segment S. Therefore, since the gap between the inner peripheral surface of the excavator body 11 and the outer peripheral surface of the existing segment S can be sealed by the tail packing 44, soil, water, etc. from the gap into the excavator body 11 Can be prevented.

  Here, as shown in FIGS. 1 to 4, a partition-side opening 21 is formed at the center of the bulkhead 20, and the partition-side opening 21 can be opened and closed by a partition-side opening / closing door 28. It has become. The lower end of the partition side opening / closing door 28 is rotatably supported by a lower portion of the partition side opening 21 on the rear surface of the bulkhead 20 via a hinge 29.

  That is, the partition side opening / closing door 28 is rotatable in the front-rear direction of the tunnel with the upper end at the lower end as a center of rotation, and opens toward the rear of the tunnel to open the partition side opening 21, while at the front of the tunnel The partition wall-side opening 21 is closed by rotating toward. At this time, when the partition side opening / closing door 28 is fully opened, it is disposed substantially horizontally.

  Further, a seal member is attached to the entire periphery of the opening edge of the partition wall side opening 21 or the entire periphery of the outer edge of the partition wall side opening / closing door 28. Thereby, when the partition-side opening / closing door 28 is fully closed and the partition-side opening is closed, it is possible to prevent leakage of excavated earth and sand flowing from the chamber 27 through them. In addition, the partition side opening / closing door 28 may adopt a structure that can withstand the soil water pressure from the chamber 27. For example, the partition side opening / closing door 28 may be configured by using a pressing force of a hydraulic jack that resists the soil water pressure. You may make it fully close.

  On the other hand, a cutter-side opening 34 is formed at the center of the cutter head 12, and the cutter-side opening 34 can be opened and closed by a cutter-side opening / closing door 35. The lower end of the cutter side opening / closing door 35 is rotatably supported by a lower part of the cutter side opening 34 on the rear surface of the cutter head 12 via a hinge 36.

  In other words, the cutter-side opening / closing door 35 is rotatable in the front-rear direction of the tunnel with the upper end at the lower end as the center of rotation, and by rotating toward the rear of the tunnel, the cutter-side opening 34 is opened. The cutter side opening 34 is closed by rotating toward the center.

  At this time, the cutter side opening / closing door 35 has a size and a shape that can pass through the partition wall side opening 21 when the cutter side opening / closing door 35 rotates toward the rear of the tunnel. As a result, when the cutter side opening / closing door 35 rotates toward the rear of the tunnel, the cutter side opening / closing door 35 is fully opened and substantially horizontal on the partition side opening / closing door 28 and on the lower edge 21 a of the opened partition side opening 21. When placed in this manner, it is placed substantially horizontally and is fully open. That is, the height position of the hinge 29 is the cutter side rotated toward the rear of the tunnel according to the thickness of the partition side opening / closing door 28, the thickness of the cutter side opening / closing door 35, and the height position of the hinge 36. The opening / closing door 35 is adjusted so as to be arranged substantially horizontally.

  Further, as shown in FIGS. 1 and 2, a drilling machine 51 and a plurality of chemical injectors 52 are provided in the excavator body 11 in which the partition side door 28 and the cutter side door 35 are fully closed. Can be installed. A plurality of through holes penetrating in the longitudinal direction of the tunnel are formed in the partition side opening / closing door 28, and a drilling valve 51b or an injection valve 52b is mounted in these through holes. The hole drilling machine 51 and the chemical liquid injector 52 are detachably attached to the rear surface of the partition side opening / closing door 28 so as to face the through holes and the valves 51b and 52b.

  Specifically, the drilling machine 51 has a drilling rod 51a that can be expanded and contracted. As a result, in the hole drilling machine 51, the drilling rod 51a is extended and driven in front of the face via the hole drilling valve 51b and the through hole, so that a boring hole can be drilled in the face. Yes.

  On the other hand, the front injector 52 has an injection rod 52a that can be expanded and contracted. Thereby, in the front injection machine 52, the injection rod 52a is extended and inserted into the boring hole through the injection valve 52b and the through hole to inject the chemical (hardening agent) into the ground in front of the face. It is possible. In this way, the ground can be improved by injecting the chemical into the ground in front of the face. In other words, the groundwater can be stopped by hardening the ground.

  Further, stirring blades 56 are detachably provided on the front surfaces of the bulkhead 20 and the partition-side opening / closing door 28 and the rear surfaces of the cutter head 12 and the cutter-side opening / closing door 35 constituting the inner wall surface of the chamber 27. The agitating blade 56 agitates the excavated earth and sand filled in the chamber 27. Thus, by agitating the excavated earth and sand, the soil water pressure in the chamber 27 is made uniform and the screw conveyor 41 is used. It is possible to improve sediment discharge.

  On the other hand, as shown in FIGS. 3 and 4, a traveling platform 53 can be installed in the excavator body 11 in which the partition side door 28 and the cutter side door 35 are fully opened. Yes. The traveling platform 53 extends to the installation height of the partition-side opening door 28 and the cutter-side opening / closing door 35 in the fully opened state, and the front end is connected to the partition-side opening / closing door 28 and the cutter-side opening / closing door 35 in the fully-opened state. The rear end is fixed on the existing segment S.

  A backhoe 54, which is a heavy machine, can travel on the traveling platform 53, and the backhoe 54 is opened by traveling on the overlapping partition side door 28 and cutter side door 35. The partition wall side opening 21 and the cutter side opening 34 can be passed through. That is, in the tunnel excavator 1, the backhoe 54 can be carried into the excavator body 11 between the excavator body 11 and the face without being disassembled, and can be carried out to the face side. . In addition, when a level | step difference arises between the overlapping partition side opening / closing door 28 and the cutter side opening / closing door 35 and the front end of the traveling platform 53 spanned between them, the scaffold plate 53 is horizontally placed between them. You may arrange in.

  Therefore, when the tunnel T is constructed on the hard ground Ga by the tunnel excavator 1, the plurality of shield jacks 43 are extended while the cutter head 12 is rotated as shown in FIGS. 1 and 2, and the spreader 43a. Is pushed against the existing segment S, the excavation reaction force is obtained from the existing segment S, and the excavator body 11 is advanced. Thus, the face is excavated in the hard ground Ga by the large number of disk cutters 31 and cutter bits 32 mounted on the rotating cutter head 12.

  At this time, the excavated soil generated by the ground excavation is filled into the chamber 27 through the excavated soil intake port 33 of the cutter head 12, but is injected into the chamber 27 as necessary. Stirring is performed by the stirring blade 56 together with the additive. The earth pressure gauge 55 constantly measures the internal pressure (earth water pressure) in the chamber 27, and the chamber 27 is maintained at a predetermined internal pressure by the filled excavated earth and sand. Then, the excavated earth and sand filled in the chamber 27 is discharged toward the rear of the tunnel by the rotational drive of the screw conveyor 41.

  At the same time, behind the shortened shield jack 43, the plurality of segments S are sequentially assembled in a ring shape along the inner wall surface of the tunnel T by driving the erector device 42.

  That is, the tunnel T can be excavated while stabilizing the face by filling the chamber 27 with the excavated earth and discharging the soil while the internal pressure of the chamber 27 is opposed to the earth pressure from the face. Yes. At the same time, the extension of the shield jack 43 allows the new segment S to be assembled behind the tunnel of the shortened shield jack 43 while excavating the excavation reaction force from the existing segment S.

  Here, when the excavation ground by the tunnel excavator 1 changes from the hard ground Ga such as the rock to the defective ground Gb such as the crushing zone (see FIG. 3), the tunnel excavator 1 causes the collapse of the face or the surrounding ground. As a result, the frictional force against the excavation reaction force increases and the tunnel excavator 1 may not be able to dig.

  Therefore, in the tunnel excavator 1 according to the present invention, in order to cope with the excavation of the defective ground Gb, when the defective ground Gb is encountered, the excavation is temporarily stopped. Then, the chemical solution is injected in front of the face and while improving the ground, the preceding tunnel Ta (see FIG. 3) preceding the tunnel excavator 1 is excavated using the heavy machinery until it passes the defective ground Gb.

  Specifically, first, the tunnel excavator 1 excavates the hard ground Ga. For example, when the cutter head 12 reaches the defective ground Gb, the excavation of the tunnel excavator 1 is stopped. That is, the drive of the cutter turning motor 25, the screw conveyor 41, the erector device 42, the shield jack 43, and the like is stopped.

  Next, as shown in FIG. 1, the hole drilling machine 51 and the chemical liquid injector 52 are mounted on the rear surface of the partition side door 28 in the bulkhead 20 to sequentially drill the boring holes and inject the chemical liquid. Thereby, the bad ground Gb ahead of the face is improved and hardened. Thereafter, the hole drilling machine 51 and the chemical liquid injector 52 are removed.

  And as shown in FIG. 3, the screw conveyor 41 is bent toward the downward direction or the left-right direction. At this time, the erector device 42 is retracted in advance to a position that does not interfere with the bending operation of the screw conveyor 41. Note that the bending operation of the screw conveyor 41 may be performed before the ground improvement.

  Next, the partition side opening / closing door 28 of the bulkhead 20 is fully opened and disposed substantially horizontally, and then the cutter side opening / closing door 35 of the cutter head 12 is fully opened and disposed substantially horizontally. That is, by placing the cutter-side opening / closing door 35 on the partition-side opening / closing door 28 that is fully open and substantially horizontal, the cutter-side opening / closing door 35 is fully open and substantially horizontal. .

  At this time, even if the partition-side opening / closing door 28 is fully opened and disposed substantially horizontally, the screw conveyor 41 is bent in the downward or left-right direction in advance, so the rotating partition-side opening / closing door 28 and the screw conveyor 41 Can be prevented.

  As described above, when the partition side opening / closing door 28 and the cutter side opening / closing door 35 are overlapped in the vertical direction and are fully opened, the partition side opening 21 and the cutter side opening 34 face each other in the longitudinal direction of the tunnel. The inside of the excavator body 11 and the face side communicate linearly.

  As shown in FIGS. 3 and 4, after installing the traveling pedestal 53, the backhoe 54 carried from the rear of the tunnel is overlapped by using the traveling pedestal 53 to overlap the partition wall side opening / closing door 28 and the cutter side. The vehicle travels up to the opening / closing door 35. At this time, the scaffold plate 53a may be installed.

  Next, excavation of the preceding tunnel Ta is started by the backhoe 54 through the cutter side opening 35. Thereafter, the backhoe 54 is caused to travel into the preceding tunnel Ta, and the excavation of the preceding tunnel Ta is further continued. At this time, if necessary, the ground is improved by sequentially drilling the boring hole and injecting the chemical liquid in front of the face of the preceding tunnel Ta.

  When the preceding tunnel Ta excavated by the backhoe 54 reaches the hard ground Ga, the cutter side opening 35 and the partition wall side are moved while the backboard 54 runs on the partition wall side door 28 and the cutter side door 35 that overlap each other. It passes through the opening 28 and is carried into the excavator body 11. Thereafter, the backhoe 54 is retracted to the rear of the tunnel using the traveling platform 53.

  Next, the tunnel T is continuously excavated on the defective ground Gb by excavating the tunnel excavator 1 along the excavated preceding tunnel Ta.

  In the tunnel excavator 1 according to the first embodiment described above, when the cutter-side opening / closing door 35 is fully opened and disposed substantially horizontally, the cutter-side opening / closing door 35 is placed at the lower edge of the partition wall-side opening 21. 21a and the partition-side opening / closing door 28, but the partition-side opening / closing door 28 and the cutter-side opening / closing door 35 that are fully opened may be used as a travel path for heavy machinery. It is only necessary to place it on at least one of the lower edge 21a of the partition-side opening 21 and the partition-side opening / closing door 28.

  For example, FIGS. 5 to 8 show a tunnel excavator according to the second embodiment. In this tunnel excavator, the cutter side opening / closing door 35 is placed only on the lower edge 21 a of the partition wall side opening 21. By doing so, it is fully open and substantially horizontal. At this time, the width of the upper end of the cutter side opening / closing door 35 that overlaps the lower edge 21a is formed to be smaller than the opening width of the partition side opening 21 (the length of the lower edge 21a). However, in FIGS. 5 to 8, the same members, the same configurations, and the members having the same functions are the same as in the tunnel excavator 1 according to the first embodiment shown in FIGS. 1 to 4. The description is abbreviate | omitted and the description is abbreviate | omitted.

  Furthermore, in the tunnel excavator according to the first and second embodiments described above, the partition wall side opening 21 and the partition wall side opening / closing door 28 are used as a travel path for heavy machinery when excavating the preceding tunnel Ta. It can also be used for other purposes.

  For example, the partition-side opening / closing door 28 is fully opened and the partition-side opening 21 is opened, whereby the belt conveyor with a hopper is inserted into the chamber 27 through the opened partition-side opening 21. As a result, the tunnel excavator can be changed to an open tunnel boring machine for excavating a tunnel in hard ground such as a rock that is self-supporting. At this time, by installing the belt conveyor with hopper on the partition-side opening / closing door 28 that is fully open and substantially parallel, the belt conveyor with hopper can be easily and accurately attached.

  When exchanging the disk cutter 31 and the cutter bit 32 mounted on the cutter head 12, the partition side opening / closing door 28 is fully opened and the partition side opening 21 is opened, so that the replacement operation is performed in the chamber. 27 can be performed. This eliminates the need for the operator to go to the face side, so that the cutter replacement operation can be performed safely.

  Therefore, when the leading tunnel Ta can be excavated from the excavator body 11 with respect to the face opened forward through the opened partition wall side opening 21 and the cutter side opening 34, the cutter side opening / closing door 35 is A position in which the bulkhead 20 is installed in the tunnel front-rear direction is brought into contact with at least one of the fully opened partition side opening / closing door 28 and the lower edge 21a of the opened partition side opening 21 to be fully opened. Or, without changing the length of the chamber 27 in the longitudinal direction of the tunnel, the heavy equipment such as the backhoe 54 can be used without being disassembled. Therefore, excavation work when excavating the preceding tunnel Ta to the defective ground Gb can be easily performed while suppressing the length of the excavation main body 11.

  In addition, since the traveling platform 53 can be installed when excavating the preceding tunnel Ta, the backhoe 54 can easily travel to the face through the fully opened partition side door 28 and the cutter side door 35. Can do. Further, since the screw conveyor 41 can be bent in the vertical direction and the horizontal direction, the rotating partition side door 28 and the screw conveyor 41 can be prevented from contacting each other. Furthermore, by making the hole drilling machine 51 and the chemical liquid injector 52 detachable on the rear surface of the partition side opening / closing door 28, only when the ground drilling machine 51 and the chemical liquid injector 52 are improved in front of the face. Since it can be installed, the damage and failure of them can be minimized.

  In addition, about the partition side opening / closing door 28, according to the occupation state of the partition side opening / closing door 28 in the excavator main body 11, it is good also as a division | segmentation structure which consists of a some opening / closing door piece, for example, the division structure divided | segmented into 2 in the up-down direction. Alternatively, it may be divided into two parts in the left-right direction.

  The tunnel excavator according to the present invention can perform the switching operation between the tunnel construction specification corresponding to the hard ground and the tunnel construction specification corresponding to the bad ground in a short time. In addition, it can be used extremely beneficially.

DESCRIPTION OF SYMBOLS 1 Tunnel excavator 11 Excavator main body 12 Cutter head 20 Bulkhead 21 Bulkhead side opening 21a Lower edge 27 Chamber 28 Bulkhead opening / closing door 34 Cutter side opening 35 Cutter side opening / closing door 41 Screw conveyor 43 Shield jack 51 Drilling machine 52 Chemical injector 53 Traveling platform 54 Backhoe Ga Hard ground Gb Bad ground S Segment T Tunnel Ta Preceding tunnel

Claims (5)

A cutter head supported rotatably at the front of the excavator body, and excavating a face on the ground;
A partition wall provided in the excavator body, and forming a chamber between the cutter head and a chamber for storing excavated earth and sand generated by excavation of the cutter head;
A cutter-side opening that is formed in the cutter head and communicates between the face and the chamber;
A cutter-side opening / closing door that opens the cutter-side opening by rotating the upper end toward the rear of the tunnel with the lower end as a rotation center;
A partition-side opening formed in the partition and communicating with the inside of the chamber;
A partition side opening / closing door that opens the partition side opening by rotating the upper end toward the rear of the tunnel with the lower end as a rotation center,
When the leading tunnel can be excavated from the inside of the excavator body with respect to the cut face opened forward through the opened cutter side opening and the bulkhead side opening, the fully opened cutter side opening / closing door is fully opened. A tunnel excavator, wherein the tunnel excavator is in contact with at least one of the partition-side opening / closing door and the opened partition-side opening. The tunnel excavator according to claim 1,
A tunnel excavator characterized in that it is connected to the fully opened bulkhead opening / closing door and is equipped with a traveling platform that allows a heavy machine for excavating the preceding tunnel to travel. The tunnel excavator according to claim 1 or 2,
A screw conveyor that discharges the excavated sediment stored in the chamber toward the rear of the tunnel of the excavator body;
A tunnel excavator characterized in that the screw conveyor can be bent in the vertical and horizontal directions of the tunnel. The tunnel excavator according to any one of claims 1 to 3,
On the rear surface of the partition side opening / closing door,
A drilling machine that drills a boring hole in front of the face,
A tunnel excavator characterized by detachably providing a chemical injection unit that injects a chemical into a boring hole drilled by the drilling machine and hardens the ground in front of the face. The cutter head and the partition wall provided in the excavator body are configured to remove excavated earth and sand generated by excavating the face while excavating the face on the ground by the rotation of the cutter head provided at the front of the excavator body In a tunnel construction method in which a tunnel is dug by taking it into a chamber formed between and discharging it to the rear of the excavator body,
During excavation of the tunnel, when it changes to bad ground, the excavation is paused,
Bending the screw conveyor that discharges the excavated soil
The cutter side opening / closing door is rotated toward the rear of the tunnel to open the cutter side opening formed in the cutter head, and the partition side opening / closing door is rotated toward the rear of the tunnel to form the partition. Open the partition wall side opening,
The fully opened cutter-side opening / closing door is brought into contact with at least one of the fully-opened partition-side opening / closing door and the opened partition-side opening,
A tunnel construction method, wherein a preceding tunnel is excavated from the excavator body with respect to the face opened forward through the opened cutter side opening and the partition side opening.

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