JPH1193562A - Branch shield excavation method and shield excavator capable of branch excavation - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To simplify and reduce the structure of a main line shield excavator, to increase work efficiency associated with branch start and reduce excavation cost, and the like. A rear body of a shield machine 1 for tunneling a main line is omitted, a plurality of shield jacks and an erector device are provided in a front body 3, and a branching and closing sealing portion 46 is provided in a middle body 4 to branch. The lining member C is assembled in the shaft Ta in front of the point, and the lining member C is reinforced by the main pushing jack device 60 installed in the shaft Ta, and the shield member in the front trunk 3 through a plurality of shield jacks. The excavation thrust is transmitted to the forebody 3 to dig up to the branch point, and the branch line shield excavator 50 is branched and started at the branch point via the branch start sealing portion 46. After the branch start, the shield excavator 1 uses the erector device. To excavate the lining member and generate excavating thrust by a plurality of shield jacks.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a branch shield excavation method and a shield excavator capable of branch excavation, and more particularly, to generate excavation thrust by a main pushing jack device provided in a vertical shaft before reaching a branch point. The present invention relates to a branch shield excavation technique in which a branch line shield excavator is branched and started, and after the branch start, the branch line shield excavator is independently excavated by a main line shield excavator and a branch line shield excavator.

[0002]

2. Description of the Related Art When excavating various shield tunnels (tunnels) for water supply and sewerage and communication cables with a shield excavator,
Often, a small diameter branch tunnel is forged from the middle of the tunnel. In the case of branch excavation, usually, the main tunnel is excavated with the main line shield excavator, and when arriving at the branch point, the branch line shield excavator is branched rightward or leftward from the main line shield excavator. After the start, the main tunnel is excavated independently with the main line shield excavator using the main line shield excavator.

For example, Japanese Unexamined Patent Publication No. Hei 8-165883 discloses a shield excavator capable of branching and excavating, such as a cutter disk, a front trunk, a middle trunk, a rear trunk, a plurality of face-face shield jacks near the rear end of the front trunk, and a rear excavator. Equipped with a plurality of shaft-side shield jacks provided near the front end of the trunk, an erector device provided in the rear trunk, a branch starter and a branch line shield excavator provided in the middle trunk, and a shield excavation in which the middle trunk has a triple structure. Machine is listed. Before reaching the branch point, the shield excavator capable of branch branching excavates while generating excavation thrust by the shaft-side shield jack, and extends the triple-structured middle body at the branch point to open the branch launch window. Then, the branch line shield excavator is started, and thereafter, the inner double structure of the middle trunk and the rear trunk are separated from the front trunk, and excavation is performed by generating excavation thrust by the face-side shield jack.

Further, Japanese Unexamined Patent Publication No. Hei 8-165885 discloses a shield machine capable of branching and excavating which is improved from that described in the above-mentioned official gazette. In this shield excavator, the inner trunk has a single-layer structure. A branch start window, a guide cylinder extending a predetermined length from the outer periphery of the window into the excavator, and a front end inserted into the guide cylinder are inserted into the inner trunk. And a filler such as mortar filled in the guide tube.

[0005] In the shield excavator capable of branch excavation described in the latter publication, as shown in FIGS. 7 to 9, a main line shield excavator 70 comprises a cutter disk 71, a front trunk 72, a middle trunk 73, and a rear trunk. And a main line shield machine 70
Is segment S on the tunnel pit wall by the erector device 75
While assembling, the excavation thrust is generated while taking a reaction force to the segment S by the shield jack 76 to dig through the main line tunnel, and when reaching a predetermined branch point, the branch line shield excavator 80 is driven by the shield jack by the shield jack. While receiving a reaction force between the force receiver 81 and the reaction force support member 82 in front of the force receiver 81, the filler material 84 is excavated by the cutter disk 83 to branch and start to the outside of the shield machine 70. After the branch line shield excavator 80 starts branching, the main line shield excavator 70 and the branch line shield excavator 80 excavate the tunnel, respectively.

[0006]

As described above, in a conventional shield excavator capable of branch excavation, a plurality of shield jacks are provided near the front end of the rear trunk, and an erector device is provided in the rear trunk. Excavation while generating excavation thrust through the reinforced segment by the shield jack. As described above, since it is necessary to equip the rear fuselage, the length of the main line shield excavator increases, the size of the machine increases, and the equipment cost also increases.

Further, after the branch line shield excavator branches off and starts, the rear trunk, in addition to the middle trunk, is left underground and discarded, which is disadvantageous in terms of equipment cost. Moreover, equipment costs are increased because a plurality of face-face shield jacks and a plurality of shaft-side shield jacks are provided. After the start of the branch, it is necessary to relocate the erector device in the rear body to the front body, so that disassembly and assembly costs are also required. An object of the present invention is to simplify the structure of a shield excavator for tunnel excavation on a main line, to increase the efficiency of various operations involved in branch start, and to reduce excavation costs.

[0008]

According to a first aspect of the present invention, there is provided a branch shield excavating method in which a main tunnel is excavated by a shield excavator, and a branch line shield excavator is branched and started from the shield excavator at a predetermined branch point. In the shield excavation method, a shaft which is connected to the main line tunnel is formed at a halfway point before reaching the junction, and a main jacking device is installed in the shaft, and the shield excavator reaches the junction after passing through the shaft. In the meantime, a lining member for lining the inner surface of the main line tunnel is assembled on the inner surface of the main line tunnel in the shaft, and is pushed toward the shield excavator side by the original push jack device, and the thrust of the original push jack device is applied to the lining member. And transmitted to the shield excavator via the digger.

[0009] Here, of the main line tunnel, a portion of the main line tunnel before reaching the shaft is excavated with a normal shield which is not capable of branch excavation, and a portion of the main line tunnel after the shaft is carried out from the shaft so that branch excavation is possible. It shall excavate with a shield excavator. When or before the main line tunnel reaches the shaft, a shield excavator that can branch into the shaft and a main jack device are carried in from the shaft, and the shield excavator that can branch and reach the shaft reaches the branch point after passing through the shaft. In the meantime, a lining member (for example, a segment or a fume pipe of a predetermined length) for lining the inner surface of the main line tunnel is assembled on the inner surface of the main line tunnel in the shaft, and pushed toward the shield machine by the main push jack device. The thrust of the main jacking device is transmitted to the shield excavator via the lining member to excavate.

According to a second aspect of the present invention, there is provided a shield excavator capable of branching and excavating, comprising: a cutter disk, a front body, a cutter rotation driving means, and a middle body releasably connected to a rear end of the front body.
Equipped with a thrust generating means for generating thrust for excavation, and a branch start mechanism formed in the middle trunk, a branch line shield excavator that excavates a branch tunnel that branches from the middle of the main line tunnel can be started via the branch start mechanism In a shield excavator capable of branch excavation, the thrust generating means is provided inside the front fuselage, and passes through a shaft formed in a vertical shaft formed so as to be connected to the main tunnel at a halfway point before reaching the branch point. A main push jack device for generating a digging thrust by pushing a lining member wrapped on the inner surface of the main line tunnel between a later shield excavator and a shaft, to generate a digging thrust. .

[0011] As in the first aspect, of the main tunnel,
The part of the main line tunnel before reaching the shaft is excavated with a normal shield that cannot branch and excavate, and the part of the main line tunnel after the shaft is excavated with a branch excavator that can be branched and carried in from the shaft. When or before the main line tunnel reaches the shaft, a shield excavator that can branch into the shaft and a main jack device are carried in from the shaft, and the shield excavator that can branch and reach the shaft reaches the branch point after passing through the shaft. In the meantime, a lining member (for example, a segment or a fume pipe) for lining the inner surface of the main line tunnel is assembled to the inner surface of the main line tunnel in the shaft, and the lining member is pushed forward by the original pushing jack device in the excavation direction. It moves and excavates while generating excavation thrust through the lining member by the thrust of the main pushing jack device.

When the vehicle reaches the branch point, the branch line shield excavator is branched and started via the branch and start mechanism provided on the middle body, and after the branch and start, the connection of the middle body to the front body is released, and the middle body is disconnected. The shield tunneling machine is driven by the thrust generated by the thrust generating means while being left in the ground to excavate the main tunnel. The thrust generating means is constituted by a plurality of shield jacks provided inside the front trunk.
As described above, when excavating from the shaft to the branch point, the extruding thrust is generated by the main pushing jack device, so that the rear body and a plurality of shield jacks provided near the front end thereof can be omitted, and the erector device is also used for the rear body. It is not necessary to equip the front fuselage with the erector device and the thrust generating means in advance.

According to a third aspect of the present invention, there is provided a shield excavator capable of branching and excavating according to the second aspect of the present invention, wherein an outer peripheral portion inside the inner trunk is excavated from a lining member lining the inner surface of the main line tunnel to the front trunk. A thrust transmitting member for transmitting thrust is provided. Therefore, the thrust transmitting member can surely transmit the digging thrust generated by the main pushing jack device from the lining member lining the inner surface of the main line tunnel to the front trunk.

According to a fourth aspect of the present invention, there is provided a shield excavator capable of branching and excavating, wherein the thrust generating means comprises a plurality of double-acting shield jacks disposed in the front fuselage. Is transmitted to the front body through a plurality of shield jacks. Since the double-acting shield jack has oil chambers on both sides of the piston inside it, if the oil pressure filled in both oil chambers is blocked, it will be almost rigid,
Excavation thrust can be transmitted.

According to a fifth aspect of the present invention, there is provided a shield excavator capable of branch excavation according to the second, third or fourth aspect of the present invention, wherein the branch start mechanism is made of a new material concrete which can be excavated by the branch line shield excavator. It has a part. The new material concrete is a non-strength concrete in which carbon fiber or glass fiber is mixed in concrete, for example. Therefore, when the branch line shield excavator is to be branched and started from within the main line shield excavator, the new material concrete branch start / stop portion in the branch / start mechanism is excavated with the branch line shield excavator and easily branched and started. be able to.

According to a sixth aspect of the present invention, there is provided a shield excavator capable of branch excavation according to the fifth aspect of the present invention, further comprising an erector device for assembling a segment inside the front fuselage. In a state where the connection between the front trunk and the middle trunk is released, the excavation is performed by the excavation thrust generated by the thrust generating means. Since the erector device is mounted inside the front fuselage, there is no need to move the erector device from inside the rear trunk to inside the front trunk after branching and starting. After the branch start, the main tunnel can be excavated by the excavation thrust generated by the plurality of shield jacks (thrust generating means) provided in the front fuselage, with the middle trunk abandoned in the ground.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment relates to a shield excavator capable of branching and excavating a shield tunnel (tunnel) and a branch shield excavating method thereof. In the following description, the excavation direction will be referred to as front, and the left and right will be described as left and right toward the front. . As shown in FIG. 1, a shield excavator capable of branch excavation is basically composed of a shield excavator 1 excavating a main tunnel, a branch line shield excavator 50 excavating a branch tunnel, and a main pushing jack device 60. It is configured. The shield machine 1 includes a cutter disk 2 for excavating a face, a cylindrical front body 3, a cylindrical middle body 4 releasably connected to a rear end of the front body 3, and a front body 3. It has an installed erector device 5, a mud discharging mechanism 6 for discharging the excavated earth and sand to the outside, and the like.

First, the cutter disk 2 will be described. As shown in FIG. 1, a cutter disk 2 for excavating a face is provided at a front end portion of the shield machine 1. The cutter disk 2 includes a plurality of cutter spokes 11 and a plurality of cutters attached to the cutter spokes 11. The cutter disk 2 includes a bit 12, an annular annular frame 13 extending rearward from the outer peripheral portion of the cutter spoke 11, and the like, and the outer peripheral portion of the annular frame 13 is supported by an annular support portion 15 at the front end of the front body 3. It is rotatably supported by receiving it through. A chamber 14 for storing excavated earth and sand is formed between the cutter disk 2 and the front body 3.

Next, the front body 3, its attached members and its internal equipment will be described. As shown in FIG. 1, the front body 3 is made of a steel cylindrical body, and an annular support portion 15 for rotatably supporting the cutter disk 2 is provided on the inner surface of the front end of the front body 3, and inside the inside thereof. Is provided with a partition wall 16, an annular ring web 17 is fixed to an inner surface of a front portion of the front body 3, and an annular ring web 18 is provided on an inner surface of the front body 3 at an intermediate portion in a longitudinal direction.
A ring member 19 is fixed to the inner surface of the front body 3 on the rear side of the ring web 18, and a ring-shaped connection fitting 20 is provided on the inner surface of the rear part of the front body 3, and a ring-shaped connection is provided. The front end of the metal fitting 20 is bolted to the ring member 19 so as to be released.

Inside the front body 3, in addition to the connection fitting 20, a plurality of cutter drive motors 21 (hydraulic or electric motors) for rotating and driving the cutter disk 2 and a lining member (segment or fume tube) are covered. There are provided an erector device 5, a plurality of shield jacks 22 (thrust generating means), a sludge discharging mechanism 6, a swivel joint 23, and the like, and a tail seal 24 provided at a rear end of the front body 3. .
The swivel joint 23 is a joint for supplying hydraulic pressure to a copy cutter (not shown) of the cutter disk 2.

A plurality of cutter driving motors 21 are fixed to the ring web 17, and a ring gear 25 is provided on the inner surface of the annular frame 13 of the cutter disc 2. A pinion 26 fixed to the output shaft of each cutter driving motor 21 has a ring gear 25. The cutter disk 2 is driven by a plurality of cutter drive motors 21 through a ring gear 25 in forward and reverse rotations.

The plurality of shield jacks 22 are disposed between the ring webs 17 and 18 near the outer periphery of the inside of the front body 3 with the piston rods facing rearward. The front end of the jack body of each shield jack 22 is a ring web. 17
And the rear end of the jack body is
An eccentric fitting 27 having a hemispherical convex portion is fixed to the rear end of the piston rod. A spreader 28 is connected to the eccentric fitting 27, and the spreader 28 is in contact with the front end of the ring member 19.

Each shield jack 22 is composed of a double-acting hydraulic cylinder, has oil chambers on both sides of the piston portion, and when the oil pressure filled in these oil chambers is blocked, the rear push jack device 60 will be described later. The excavation thrust transmitted via the lining member C (in the present embodiment, a ring-shaped fume pipe) for lining the inner surface of the main line tunnel T can be transmitted to the front body 3. The plurality of shield jacks 22 are applied to the transmission of the excavating thrust as described above before the branch shield excavator 50 branches, and are applied to generate the excavation thrust after the branch shield excavator 50 branches. Note that a segment may be applied as the lining member C.

An erector device 5 is provided in the middle part of the front body 3 in the longitudinal direction for mounting the segment over the entire inner peripheral surface of the tunnel pit wall. The erector device 5 includes a front body 3, a ring web 18, and a ring member 19.
An erector frame 31 rotatably disposed in the erector frame 31, a driving mechanism 32 including a motor for rotating the erector frame 31, and a central portion of the erector frame 31 and disposed on the rear side of the erector frame 31. Erector body 33 and the like.

The sludge discharging mechanism 6 is a sludge pipe 3 fixed to the partition 16 so as to penetrate the partition 16 and opened into the chamber 14.
4, a drain pipe 35 fixed to the partition 16 so as to penetrate the partition 16 and provided to be able to suck muddy water in the chamber 14;
A communication pipe 36 for connecting the mud feeding pipe 34 and the mud discharging pipe 35, and valves 37 to 39 interposed in these pipes 34 to 36, respectively.
And a mud feed hose 4 connected to the mud feed pipe 34 and extending rearward.
0, and a sludge hose 41 connected to the sludge pipe 35 and extending rearward.

Next, the inner trunk 4 and its attached members will be described. As shown in FIG. 1, the middle body 4 is made of a steel cylindrical body, and an annular ring web 42 is fixed to an inner surface of a front end of the middle body 4, and an annular ring web 4 is fixed to an inner surface of a rear end of the middle body 4.
A receiving seat 43 similar to 2 is fixed. The ring web 42 at the front end of the inner trunk 4 is connected to the rear end of the connection fitting 20 by a plurality of bolts. Ring web 42 and seat 43
In the meantime, a plurality of thrust transmitting members 44 are disposed in the front-rear direction near the outer periphery of the inside of the inner trunk 4, and configured to transmit the excavating thrust transmitted from the lining member C to the connection fitting 20. It is. Each thrust transmitting member 44 is formed by connecting two steel pipe members in series.

As shown in FIG. 1 and FIG. 2, in order to branch and start the branch line shield machine 50 from the longitudinal center of the middle body 4 of the shield machine 1 at the branch point, The following branch start mechanism 45 is provided. In the case of the present embodiment, the branching and starting mechanism 45 is provided at a middle portion on the right side at the center in the length direction of the middle body 4. The branching / starting closing portion 46 of the branching / starting mechanism 45 is circular (slightly larger in diameter than the outer diameter of the branch line shield excavator 50) in a side view as viewed from the inside, and is much more remarkable than the middle trunk 4. It is made of thick unstretched new material concrete.

The new material concrete may be any concrete as long as it can close the branching and closing sealing portion 46 with sufficient strength and can excavate with the cutter disk 51 of the branch line shield excavator 50. The new material concrete is, for example, concrete obtained by mixing reinforcing fibers (for example, any of glass fiber, carbon fiber, fibrous pulp, etc.) into mortar and hardening. The branch line shield machine 50 is a branch start mechanism 4
When the vehicle starts branching through the branch 6, the cutter disk 51 of the branch line shield excavator 50 uses the branching and closing seal 46.
Is excavated and destroyed, and branches off to the outside of the middle trunk 4.

When the branch line shield excavator branches and starts from the outer peripheral portion to the inner side of the branch and start closing portion 46,
A steel packing case 47 and a waterproof packing 48 for preventing muddy water from entering the inside of the shield machine 1 are provided. The packing case 47 is welded to the inner surface of the inner trunk 4 in a horizontal state orthogonal to the inner trunk 4, and has a size that allows the branch line shield excavator 50 to pass therethrough. A water-stop packing 48 is provided inside the packing case 47 so that the tip thereof abuts on the outer peripheral surface of the front trunk 52 of the branch line shield excavator 50.

Next, the branch line shield machine 50 will be described. However, the excavation direction will be referred to as the front, and left and right toward the front will be referred to as left and right. The branch line shield excavator 50 is carried from the shaft Ta into the inside of the middle trunk 4 of the shield excavator 1 when reaching the branch point, and is packed so as to face the branch start sealing part 46 as shown in FIG. The case 47 is set in a state where the cutter disk 51 is inserted. The branch line shield excavator 50 includes a cutter disk 51 for excavating a face like the shield excavator 1.
, A cylindrical front trunk 52, a plurality of shield jacks 53 inside the front trunk 52, a rear trunk 54 connected to the rear end of the front trunk 52, and a lining member (in this embodiment, a ring-shaped An erector device for attaching the fume pipe, and a sludge discharging mechanism for carrying excavated earth and sand to the outside are provided. still,
A segment may be used as the lining member, and when the branch tunnel has a small diameter, the erector device may be omitted.

However, first, the front trunk 52 and its internal devices are carried in, and after the start of branching, the rear trunk 54 and its internal devices are carried in and connected. As will be described later, when the branch line shield excavator 50 branches and starts after the shield machine 1 reaches the branch point, a reaction force receiver 55 is attached to the inner surface of the inner trunk 4, and the reaction force receiver 55 reduces the reaction force. Reaction force transmitting member 5 while taking
While pushing 6 on the shield jack 53, the front trunk 52 of the branch line shield machine 50 and its internal devices are advanced.

Next, the original pushing jack device 60 will be described. As shown in FIG. 4, the shield machine 1 forms a shaft Ta connected to the main line tunnel T at an intermediate point before reaching the branch point, and the main push jack device 60 is installed in the shaft Ta. This main pushing jack device 60
Generates an excavating thrust on the shield machine 1 by pushing the lining member C on the inner surface of the main line tunnel T forward until the shield machine 1 reaches the branch point after passing the shaft Ta. It is to make it.

As shown in FIG. 4, the main push jack device 60 includes a reaction force receiver 61 provided at the rear end of the shaft, a base body 62 fixed to the reaction force receiver 61, and a front surface of the base body 62. A plurality of hydraulic push jacks 63 fixed in a horizontal posture, and a ring member 64 fixed to the front end of the piston rod of these push jacks 63, the ring member receiving the rear end of the lining member C 64. The lining member C is carried in from the shaft Ta, and is sequentially assembled to the front side of the ring member 64. The lining member C lining the inner surface of the main line tunnel T is pushed forward by the original push jack device 60. The excavation thrust is transmitted from the lining member C via the plurality of thrust transmission members 44, the ring-shaped connection fittings 20, and the plurality of shield jacks 22 to the front body 3 of the shield excavator 1.
Is transmitted to

Next, a description will be given of an operation and a method of excavating the main line tunnel T by using the above-described shield excavator capable of branch excavation and branching and starting the branch line shield excavator 50 at a branch point on the way. When digging in the main tunnel T behind the shaft Ta, the mine can be digged using a normal shield excavator different from the above, and the main tunnel T between the pit TA and the branch point can be diverged and excavated. Excavation with a simple shield excavator.

A shaft Ta is formed at a desired position about several tens to 200 m before the branch point so as to communicate with the main tunnel, and the shield excavator 1 is carried in from the shaft Ta to excavate the main tunnel T. Will be done. At this time, the lining member C lining the inner surface of the main line tunnel T is driven forward by the main pushing jack device 60, and the digging thrust generated by the main pushing jack device 60 as described above is covered by the lining member. C, a plurality of thrust transmitting members 44, a ring-shaped connection fitting 20, and a plurality of shield jacks 22 are transmitted to the front trunk 3 of the shield machine 1 to excavate. With every excavation of one ring, the piston rod of the main push jack 60 is retracted,
The shield excavator 1 excavates the lining member C while repeatedly lining the lining member C on the uncovered inner surface of one ring of the front side of the ring member 64 and pushing it again with the original pushing jack 60.

The shield machine 1 is stopped when the shield machine 1 reaches the branch point and the branching and closing block 46 coincides with the branch point, and the cutter disk 51 and the front body 52 of the branch line shield machine 50 are stopped. From the shaft Ta, and as shown in FIG. 2 and FIG.
No. 0 is pushed into the packing case 47 and the reaction force transmitting member 56 supported by the reaction force receiver 55 is pushed by a plurality of shield jacks 53 to cause the branch line shield excavator 50 to advance while generating excavation thrust. , Reaction force transmitting member 56
Are sequentially excavated, and the branching and closing sealing portion 46 is excavated with the cutter disk 51 of the branch line shield excavator 50 to continue excavation.

As shown in FIG. 3 and FIG. 5, when the front trunk 52 of the branch line shield excavator 50 substantially protrudes from the branch / start sealing portion 46, a part of the reaction force transmitting member 56 is disassembled. The rear trunk 54 and its internal devices are carried in and connected to the front trunk 52, and then the reaction force transmitting member 56 is assembled to the inner surface of the trunk 54, and the reaction force transmitting member 5 is
6 and excavate with the branch line shield excavator 50 to branch and start. Thereafter, as shown in FIG. 6, a reaction force is taken by a lining member Cb (in the present embodiment, a fume tube of a predetermined length) lining the inner surface of the rear trunk 54 and the inner surface of the branch line tunnel Tb. The branch line shield excavator 50 excavates.
At the time of the branch start, the water is stopped by the packing case 47 and the water-stop packing 48. However, even if mortar is filled between the packing case 47 and the outer peripheral surface of the branch line shield excavator 50 to stop the water. Good.

After the above-described branch start, the shield excavator 1 includes the ring member 19 and the ring-shaped connection fitting 2.
0, the connection between the front body 3 and the middle body 4 is released, the shield machine 1 is prepared to be operable, and then the excavation of the main tunnel T by the shield machine 1 is resumed. I do. At this time, the plurality of shield jacks 22 are actuated, and at first, the shield jack 22 kicks the front end of the ring-shaped connection fitting 20 backward to generate excavation thrust and excavate. The middle trunk 4 and the connection fitting 20 are left behind on the inner surface of the tunnel, and only the front trunk 3 of the shield machine 1 and its attached members and its internal devices move forward. Thereafter, the lining member C is assembled to the rear inner surface of the front body 3 following the front end of the connection fitting 20 by the erector device 5, and a reaction force is applied to the lining member C which has been completed, and the plurality of shield jacks 22 are used. It excavates while generating excavation thrust.

According to the branch excavation technique described above, it is not necessary to provide a rear trunk in the shield excavator 1 and the trunk is not abandoned in the ground thereafter. Since there is no need to provide a plurality of shield jacks near the front end of the upper and rear torso, the shield excavator 1 can be excavated with a simple and small size, so that the equipment cost of the shield excavator 1 can be reduced and the tunnel excavation cost can be reduced. In addition, since an erector device for assembling the lining member is provided inside the rear trunk, it is not necessary to transfer the erector device to the interior of the front trunk 3 after the branch line shield excavator 50 starts branching. The disassembly and assembly cost for that purpose can be reduced.

Since the excavating thrust generated by the main pushing jack device 60 is transmitted to the front body 3 via the thrust transmitting member 44, the connection fitting 20, and the plurality of shield jacks 22, the plurality of shield jacks 22 are effectively utilized for excavation. Since the thrust can be transmitted, it is structurally advantageous as compared with the case where the excavation thrust is transmitted via another member. Middle body 4 of shield machine 1
In addition, a new material concrete branch-starting sealing portion 46 is provided, and the branch-starting sealing portion 46 is excavated by the branch line shield excavator 50 to branch and start. In addition, since the packing case 47 and the waterproof packing 48 are provided so as not to leak water from the outside to the inside of the inner body 4, no trouble due to the waterproof is generated.

As an example of partially changing the above-described embodiment, a plurality of connection fittings similar to the thrust transmitting member 44 can be applied instead of the ring-shaped connection fitting 20. There may be a case in which a middle bent portion is provided at a connection portion between the front body 3 and the middle body 4 and a plurality of middle bent jacks are provided. Instead of the sludge discharging mechanism 6, a discharging mechanism including a screw conveyor or the like may be applied.

[0042]

According to the first aspect of the present invention, when digging from the shaft to the branch point, a lining member for lining the inner surface of the main line tunnel is assembled in the shaft and installed in the shaft. Since the excavating thrust is applied to the shield machine via the lining member by the attached main jack device, it is installed in the rear body of the shield machine and multiple shield jacks installed near the front end and in the rear body. Therefore, a small-sized shield excavator having a simple structure in which the erector device is omitted can be applied, which is advantageous in terms of equipment cost, and can reduce tunnel excavation cost. In particular, in the case of relatively small diameter tunnels such as a tunnel for water and sewage and a tunnel for communication cables, the inner surface of the tunnel is often covered with a fume pipe, and a branch tunnel is often required. Is preferred.

According to the second aspect of the present invention, when digging from the shaft to the branch point, the extruding thrust is generated by the main pushing jack device provided in the shaft, so that the rear body and the plurality of gears provided near the front end thereof are provided. The shield jack can be omitted, and there is no need to equip the rear body with the erector device,
What is necessary is just to equip the front fuselage with an elector apparatus and a thrust generating means beforehand. Therefore, the main tunnel can be dug by a small and inexpensive shield excavator with a simple configuration in which the rear trunk normally abandoned in the ground and a plurality of shield jacks near the front end can be excavated. is there. In addition, the original pushing jack device can be reused, and the transfer from the rear trunk to the front trunk of the erector device can be omitted, so that the excavation cost can be variously reduced.

According to the third aspect of the present invention, the thrust transmitting member for transmitting the excavating thrust from the lining member lining the inner surface of the main line tunnel to the front trunk is provided on the outer peripheral portion inside the middle trunk. With the thrust transmitting member, the excavating thrust generated by the main pushing jack device can be reliably transmitted from the lining member lining the inner surface of the main line tunnel to the front trunk. The other effects are the same as those of the second aspect.

According to the fourth aspect of the present invention, the thrust generating means comprises a plurality of double-acting shield jacks disposed in the front body, and the excavating thrust from the thrust transmitting member is transmitted through the plurality of shield jacks. Since the power is transmitted to the front body, the excavating thrust can be transmitted by effectively utilizing the plurality of shield jacks, which is structurally advantageous. The other effects are the same as those of the third aspect.

According to the fifth aspect of the present invention, since the branch / start mechanism has the branch / start sealing portion made of new material concrete which can be excavated by the branch line shield machine, the branch line shield machine can be mounted inside the main line shield machine. When the vehicle is to be branched and started, it is possible to easily perform the branch and start by excavating the new material concrete branch and start seal portion in the branch and start mechanism with a branch line shield excavator. Other claim 2 or 3
It has the same effect as.

According to the sixth aspect of the present invention, there is provided an erector device for assembling a segment inside the front fuselage, and the branch line shield excavator disconnects the front trunk and the middle trunk after the branch starts. In this state, the digging is performed by the digging thrust generated by the thrust generating means, so that it is not necessary to transfer the erector device from the rear trunk to the front trunk after the branching start. After the branch start, the main tunnel can be excavated by the excavation thrust generated by a plurality of shield jacks (thrust generating means) provided in the front fuselage, with the middle trunk abandoned in the ground.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a shield machine capable of branch excavation according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a branch start blocker and a branch line shield machine.

FIG. 3 is a longitudinal sectional view of a branch line shield machine (after branch start).

FIG. 4 is a schematic plan view of a shield machine capable of branching and excavating at a branch point.

FIG. 5 is a schematic plan view of a shield machine and a branch line shield machine (after branch start).

Fig. 6: Shield excavator (main line tunnel excavation resumed)
It is a schematic plan view of a branch line shield machine (after branch start).

FIG. 7 is a schematic plan view of a shield excavator capable of branch excavation according to the related art in a state immediately before branching.

8 is a schematic plan view of the shield machine shown in FIG. 7 after the start of branching.

9 is a schematic plan view of the shield machine shown in FIG. 7 (after resuming the tunnel excavation on the main line).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield excavator 2 Cutter disk 3 Front trunk 4 Middle trunk 5 Electa device 6 Drainage mechanism 20 Connection fitting 21 Cutter drive motor 22 Shield jack 44 Thrust transmitting member 45 Branch start mechanism 46 Branch start sealing part 50 Branch line shield excavator 60 Main jack device T Main line tunnel Ta Vertical shaft Tb Branch tunnel C Lining member

Claims (6)

[Claims] 1. A branch shield excavating method for excavating a main line tunnel with a shield excavator and branching and starting a branch line shield excavator from a shield excavator at a predetermined branch point. Forming a shaft connected to the main tunnel at a point, installing a main push jack device in the shaft, and lining the inner surface of the main tunnel until the shield machine reaches the branch point after passing through the shaft. Assembling the members on the inner surface of the main line tunnel inside the shaft, pushing the main push jack device to the shield excavator side, and transmitting the thrust of the main push jack device to the shield excavator via the lining member to excavate Characteristic branch shield excavation method. 2. A cutter disk, a front body, a cutter rotation driving means, a middle body releasably connected to a rear end of the front body, a thrust generating means for generating a thrust for excavation, and a thrust generating means. A branch excavation mechanism that is formed, and a branch line shield excavator that excavates a branch tunnel that branches from the middle of the main line tunnel and that can be started via the branch start mechanism. Means are installed inside the forebody, inside the shaft formed so as to be connected to the main tunnel at a halfway point before reaching the branch point, on the inner surface of the main tunnel between the shield machine and the shaft after passing the shaft. A shield excavator capable of branching and excavating, comprising a main push jack device for generating an excavating thrust by pushing a lining member forward in the excavating direction. 3. A thrust transmitting member for transmitting excavation thrust from a lining member lining an inner surface of a main line tunnel to a front trunk is provided on an outer peripheral portion inside the middle trunk. 3. A shield machine capable of branch excavation according to 2. 4. The thrust generating means includes a plurality of double-acting shield jacks disposed in the front trunk, and a digging thrust from the thrust transmitting member is transmitted to the front trunk via the plurality of shield jacks. The shield machine capable of branching and excavating according to claim 3, characterized in that: 5. The branch start mechanism according to claim 2, wherein the branch start mechanism has a branch start / stop portion made of a new material concrete excavable by a branch line shield machine.
A shield excavator capable of branch excavation according to the paragraph. 6. An erector device for assembling a segment inside the front fuselage, wherein after the branch line shield excavator starts branching, the thrust force is released in a state where the front trunk and the middle trunk are disconnected. The shield excavator capable of branch excavation according to claim 5, wherein the excavator is configured to excavate with the excavation thrust generated by the generating means.