JPH07127377A - Shield machine and tunnel joining method - Google Patents

Abstract

PURPOSE:To excavate from opposed sides and inhibit the fall of a subsoil and simplify joint work by forming a tunnel with a side overcutter and fitting a cutter disk into a skin plate of the other shield machine when in an evaded state. CONSTITUTION:A side overcutter 24 is projected into a skin plate 23 while a rotary support member 10 is rotated so as to rotate a cutter disk 1, thereby excavating a natural ground in front of the disk 1. The side overcutter 24 to be mounted to the disk 1 is arranged to excavate a natural ground near the skin plate 23. When excavating from opposed sides with shield machines 21 while they are tunneline forward, the cutter disk 1 is fitted into the skin plate 23 of the other shield machine 21. Furthermore, at a tunnel joint area, the tunnel can be joined easily with the contact between the skin plates 23, 23 of the two shield machines 21, 21 which makes it possible to long tunnel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield machine and a tunnel joining method, and more specifically, two shield machines are made to face each other so that both tunnels communicate with each other without using a vertical shaft. The present invention relates to a tunnel junction construction method capable of forming a long tunnel and a suitable shield machine used therein.

[0002]

2. Description of the Related Art There is a limit to the distance that can be excavated by a shield machine, and when the tunnel is long, it is impossible to deal with it with only one shield machine. Therefore, conventionally, a shaft is provided within the range of the distance that can be excavated by one excavator, and excavation is performed between the coexisting shafts by each excavator
Long tunnels are joined by connecting at the vertical shaft. However, if the upper part of the tunnel is the sea or a city that is overcrowded, it becomes impossible to install a vertical shaft, and the tunnel cannot be joined by the method using the vertical shaft. Therefore, two shield excavators are dug so that they face each other, and when both reach the joining position,
Construction methods for joining tunnels are becoming popular. At the time of the joining, the ground at the joining point is frozen and the ground is improved by injecting a chemical solution and the ground is excavated.

Such ground improvement requires a large amount of cost and time. As an auxiliary construction method for solving the problem, there is a tunnel underground construction method as described in JP-A-59-192194. This is to eject a high-pressure jet from the inside of the shield main body to excavate the ground in the vicinity of the facing portion of the shield machine, and to inject a solidifying material into the excavated portion to stabilize the annular portion between the two machines. Tunnel excavation can be realized by excavating and removing earth and sand from the stabilized annular interior.

[0004]

If the auxiliary construction method is adopted as described above, the ground between the shield excavators facing each other can be strengthened, and various devices and members in the machine including the cutter disk can be disassembled, and the skin of the shield main body can be disassembled. After removing it from the plate, it is sufficient to excavate the reinforced ground between both shield machines as much as necessary for tunnel connection. However, since there is a certain amount of clearance between the opposing faces of both aircraft, although the ground is being strengthened, ground collapse or depression may occur between the aircraft, and groundwater and earth and sand may pass through the ground between the aircraft and shield the main body. There is a high possibility that it will enter inside. Especially on the ground below the seabed,
There are doubts about the reliability of ground improvement, and flooding and ground collapse may hinder excavation and hinder smooth joint work. Therefore, it is not possible to make a great contribution to the shortening of the construction period and the improvement in economic efficiency, and improvement of the joining method is desired.

The present invention has been made in view of the above problems, and an object thereof is to reduce the use of an auxiliary construction method which requires a large amount of cost as much as possible, and to minimize the risk of ground collapse, which is economical. An object of the present invention is to provide a shield machine and a tunnel joining method capable of excellently shortening the construction period and forming a long tunnel.

[0006]

The present invention is applied to a shield machine having a cutter disk for excavating the ground in the front part of a cylindrical skin plate. As for its characteristic, referring to FIG. 1, a rotatable support 10 supported by a bearing base 9 provided inside the skin plate 23 so as to be displaceable in the direction of the axis N of the shield body 2, and A cutter disk 1 integrated with the rotary support 10 via support arms 14, 14 on the front side of the rotary support 10.
A side over cutter 24 attached to the cutter disk 1 and capable of protruding to the outside of the outer diameter of the skin plate 23; a drive source 13 for rotating the cutter disk 1 via a rotary support 10; The rotary support 10, the cutter disk 1, and the drive source 13 are provided with retracting means 25 that can be retracted in the skin plate 23 by retracting in the direction of the axis N of the shield body 2.

In the invention of the tunnel joining method, FIG.
2 to 5, two shield excavators 21A, 21 are provided which allow the side over cutters 24A, 24B attached to the cutter disks 1A, 1B to project to the outside of the outer diameter of the skin plates 23A, 23B.
B is dug so as to face the tunnel junction M. The side over cutter 24A of the one shield machine 21A that has reached the tunnel junction M is retracted,
After that, the cutter disk 1A is retracted into the skin plate 23A (see FIG. 4). The other shield machine 21
B is advanced to reduce the side over cutter 24B (see FIG. 5), and only the cutter disk 1B is opposed to the skin plate 23 of the shield machine 21A.
That is, it is designed to be inserted into A.

[0008]

When the side over cutter 24 attached to the cutter disk 1 of the shield machine 21 is projected to the outside of the outer diameter of the skin plate 23 and then the drive source 13 is rotated, the side over cutter 24 is provided inside the skin plate 23. The rotary support 10 supported on the bearing base 9 is rotated. Along with the rotation, the cutter disk 1 located on the front surface side of the rotary support body 10 and integrated with the rotary support body 10 via the support arms 14 and 14 is rotated, and the ground level on the front surface of the cutter disc 1 is increased. Excavated. At this time, the side over cutter 24 attached to the cutter disk 1 also excavates the ground near the outer peripheral portion of the skin plate 23. Then, as the shield machine 21 advances, tunnels larger than the outer diameter of the skin plate 23 can be sequentially formed as needed. As shown in FIG. 4, when two shield machines 21A and 21B are made to face each other toward the tunnel junction M, when the two tunnels are joined, the retracting means 25 of one shield machine 21A is used. The bearing base 9, the rotary support 10, the cutter disk 1, and the drive source 13 are retracted in the direction of the axis N of the shield body 2 and retracted into the skin plate 23. As a result, the cutter disk 1 of the other shield machine 21B
B is the skin plate 2 of one shield machine 21A
It becomes possible to fit in 3A.

In the tunnel junction construction method, two shield excavators 21A and 21B are excavated so as to face the tunnel junction M (see FIG. 3). In each shield machine 21A, 21B, the side over cutter 2
4A, 24B are projected to the outside of the outer diameter of the skin plates 23A, 23B to form a tunnel having a desired diameter, and reach the tunnel junction M. When one shield machine 21A reaches the tunnel junction M, the side over cutter 24A is stored in the cutter disk 1A so as to retract into the skin plate 23A. Then, the retracting means 25 retracts the bearing base 9, the rotary support 10, the cutter disk 1, and the drive source 13 in the direction of the axis N of the shield body 2 and retracts into the skin plate 23A. In the other shield machine 21B as well, if the side over cutter 24B is projecting, it is stored in the cutter disk 1B, and the cutter disk 1B is retracted by the cutter disk 1A from inside the skin plate 23A of the shield machine 21A. The other shield machine 21B is moved forward so as to fit into the space. Tunnel junction M
In, the two shield excavators 21A, 21B contact or close to the skin plates 23A, 23B,
The tunnel can be easily joined, and it is possible to form a long tunnel by suppressing the use of an expensive auxiliary construction method as much as possible.

[0010]

According to the shield machine of the present invention, the side over cutter is projected from the cutter disk beyond the outer diameter of the skin plate, and a tunnel having a diameter which cannot be achieved by excavating the cutter disk is required. Can be formed accordingly. Also, when excavating a long tunnel using two shield excavators, the cutter disk is retracted into the skin plate at the time of joining the two tunnel excavators, and the other shield excavator is realized to bring the tunnel excavator closer. The joining work can be facilitated and facilitated.

According to the tunnel joining method, the cutter disk of one shield machine and the cutter disk of the other shield machine can be brought close to each other with a very small distance, and one side and the other side. When excavating the natural ground to form a long tunnel, it is possible to eliminate or extremely reduce the ground that is continuous with the natural ground between both shield excavators facing each other at the tunnel junction. As a result, it is not necessary to employ a large-scale auxiliary construction method such as improvement of the ground, or only an extremely small area can be improved. Therefore, a vertical shaft is not required, the construction period can be greatly shortened, the construction safety can be ensured at a high level, and the construction cost can be remarkably reduced.

[0012]

The present invention will be described in detail below based on its examples. FIG. 1 shows a shield machine 21 according to the present invention.
In the vertical sectional view of FIG. 1, the cutter disk 1 can be retracted into the skin plate 23 by reducing the retracting means 25. This example is a muddy water shield machine, which has a bulkhead 5 that partitions the machine room 3 to form a cutter chamber 4 in the front, and a mud pipe 6 and a mud pipe 7 penetrate into the cutter chamber 4 through the bulkhead 5. It has been opened. Then, the cutter disk 1 that is rotated by mounting the cutter for excavating the face 8 which is the natural ground is the shield body 2
Support 10 located on the front of the bearing and supported on the bearing base 9.
Is rotated by power from a drive source 13 such as a hydraulic motor that is transmitted via the pinion 11 and the slewing bearing 12.

The cutter disk 1 has support arms 14, 14
The rotary support body 10 is integrated with the rotary support body 10 via a seal member, and seal members 15 and 16 are provided at sliding portions of the rotary support body 10 for rotating the cutter disk 1. Are prevented from entering the plane. A plurality of shield jacks 17 (one shown in the drawing) are installed on the periphery behind the bearing base 9, and an annular segment 19 built inside the tail plate 18 can take a reaction force for excavation. it can. On the other hand, at the rear of the machine room 3, the erector device 2 for assembling the segment 19 is installed.
When there is 0, and the shield body 2 is stopped after advancing, the arc-shaped segments are sequentially assembled in an annular shape.

The above construction is no different from what is commonly seen in the past, and a trailing shield machine 21B (see FIG. 2) described later will suffice.
However, as described above, FIG. 1 shows the shield machine 21 capable of retracting the cutter disk 1, and in addition to the above-mentioned configuration, a drive system including a drive source 13 such as a pinion 11, a slewing bearing 12 and a hydraulic motor. A pull-in jack is provided as a pull-in means 25 for integrally retracting the cutter disc 1 and the cutter disc 1 in the direction of the axis N of the shield body 2 and retracting them into the skin plate 23.

That is, the bearing base 9 described above is slidable with respect to the skin plate 23 forming the outer shell, and can be retracted together with the drive system 22 and the bulkhead 5 as the retractable jack 25 is reduced. On the other hand, a side over cutter 24 is attached to the cutter disk 1, and by moving the side over cutter 24 in the radial direction, the side over cutter 24 can be projected outside the outer diameter of the skin plate 23. In order to allow the cutter disc 1 to retract as described above, the skin plate 23 cannot be integrated with the bearing base 9, and the skin plate 23 at the front part of the shield body 2 is thicker than at the rear part. It is considered to be meat and its rigidity is improved. Then, in order to retract the bearing base 9 in the direction of the axis N of the shield body 2, as described above, the retractable jacks 25 that are reduced in size are arranged alternately with the shield jacks 17 in the circumferential direction, for example. . This retractable jack 25 has its piston rod 2
The rear end 5a is fixed to the shield body 2, and the cylinder body 25b is supported so as to be displaceable with respect to the reinforcing ring 26.

By the way, the drive system 22 is moved with respect to the skin plate 23 at the time of tunnel joining, but needs to be fixed when excavating. At that time, the pull-in jack 25 is maintained in an extended state, and the skin plate 23 and the bearing base 9 are brought into close contact with and integrated with each other, and an unshaped material for preventing intrusion of groundwater is provided. Is filled. The filler is, for example, an epoxy resin,
Care is taken to ensure a gap for moving the bearing base 9 with respect to the skin plate 23. Since the shield jack 17 which receives the excavation reaction force needs to be in contact with the bearing base 9, the spacer 27 having a length corresponding to the retreat distance of the cutter disk 1 is removably interposed.

Such a shield machine 21 functions as a leading shield machine 21A, as shown in FIG.
The cutter disk 1A is retracted by the length of the spacer 27 described above, and inside the skin plate 23A,
As will be described later, when the trailing shield machine 21B advances, the cutter disk 1B can enter and fit. As a result, the skin plate 23A of the leading shield machine 21A and the skin plate 23B of the trailing shield machine 21B can come into contact with each other or can be close to each other with a slight gap left therebetween. The ground at the joint position is
It is supported by the two cylindrical skin plates 23A and 23B or the outer ring 1b of the cutter disk 1B, and can prevent the ground from collapsing or sinking. Further, the amount of groundwater and earth and sand that enter between the two shield machines 21A and 21B is reduced, and in this example, it is possible to stop the water or to prevent the inflow by injecting a solidifying material described later. it can.

The shield machine 21A, 2 having the above structure
The tunnel excavated by 1B is as follows.
It can be joined in the ground without using a vertical shaft to form a long tunnel. As shown in FIG. 3, the two shield excavators 21A and 21B are excavated to face the tunnel junction M. As shown in FIG. 4, the leading shield machine 21A is made to reach the tunnel junction M first, and is stopped at that position.

Next, the side over cutter 24A of the shield machine 21A on one side is contracted to prepare for retracting the cutter disk 1A into the skin plate 23A. Therefore, the spacer 27 (see FIG. 1) interposed as a supporting member between the bearing base 9 and the shield jack 17 is removed. The retracting jack 25 is contracted to retract the cutter disk 1A, and a chemical solution is injected into the front space 30 of the skin plate 23 to prevent the ground from collapsing. In that state, the other shield machine 21B is brought closer to the stopped shield machine 21A, and the side over cutter 24B is reduced as shown in FIG. And
Only the cutter disk 1B is fitted into the skin plate 23A of the leading shield excavator 21A so as to excavate while rotating the cutter disk 1B, so that the cutter disk 1B approaches the cutter disk 1A.

Therefore, via the injection pipes 31A and 31B penetrating the illustrated bulkheads 5 and 5, inside the cutter chambers 4A and 4B of both shield machines 21A and 21B and the facing gaps of the cutter disks 1A and 1B. The solidifying material is injected as shown in FIG. When it is difficult to completely insert the cutter disk 1B into the skin plate 23A of the leading shield machine 21A, as shown in FIG. 7, the tip of the cutter disk 1B slightly overlaps the skin plate 23A. After advancing to, the solidifying material may be injected. When the solidifying material solidifies, either shield machine 21A, 21B
The various devices and members inside the machine are disassembled, leaving the skin plates 23A and 23B of the shield machine 23 as shown in FIG.
Removed from A, 21B. Then, both skin plates 23A, 23B and the outer ring 1b (see FIG. 9) of the cutter disk 1B of the trailing shield machine 21B are left, and in that state, the tunnel wall is provided between the inner periphery of the segment 19 and the solidified material injecting portion. The concrete 32 is poured. After that, the solidified material injection portion is hollowed out and opened as shown in the drawing. As shown in the figure, there is a very small gap between the opposing surfaces of the two machines or they are in contact with each other, and the solidifying agent is effectively filled, so there is almost no need to improve the ground at the joining point. It prevents the ground from collapsing and sinking.

FIG. 10 is an example of a different injection method of the solidifying material in FIG. For example, in the trailing shield machine 41B shown in FIG. 11, for example, three injection holes 4 (two in the figure) are provided on the peripheral surface of the outer ring 1b of the cutter disk 1 at 120 degrees apart.
2, 42 are provided so that the solidified material is injected between the outer ring 1 b and the skin plate 23. The solidifying material is injected while rotating the cutter disk 1 between the above-described FIG. 5 and FIG. Since the solidifying material is not injected during the excavation until reaching the joining point, the check valve 43 is provided so that groundwater does not flow backward from the injection hole 42 and sand or the like does not cause clogging. Figure 10
It is provided as shown in. The pipe for supplying the solidifying material to the injection hole 42 is installed in the rotary support 10 or the support arm 14. Since this rotates integrally with the cutter disk 1B, the solidified material sent from the rear of the shield body is supplied to the annular passage 45 communicating with it through the radial passage 44 provided on the rear surface of the bulkhead 5. It is like this. Then, it can be circulated to the connecting pipe 47 fixed to the rotary support 10 through the annular cover 46 that slides and rotates in the annular passage 45.

The cutter disk 1B for injecting the solidifying material described above is not limited to the case where it is completely projected to the front surface of the shield machine 21B, but the disk width W is wide and a part of the rear part as shown in FIG. Is also effective in the case of an arrangement in which is left in the skin plate 23B. That is, since the solidifying material is injected from the outer ring 1b, it becomes easy to fill the gap 48 (see FIG. 10) between the skin plates 23A and 23B which are in the approaching or abutting state of the shield machine 21A and 21B. , It is possible to reliably prevent intrusion of groundwater into the shield body. Since the cutter disc 1 cannot be made larger than the outer diameter of the skin plate 23, the side over cutter 49 that moves in and out in the radial direction of the cutter disc 1 projects forward from the skin plate 23 as shown in FIG. It is placed so that it can move in and out only in a part, and it is moved slightly forward.

If the shield machine having such a structure is used, as in the case shown in FIG. 2, the work of joining the two shield bodies becomes smooth, and the work period is shortened and the economy is improved. In addition, between the cutter disk 1B and the skin plates 23A and 23B, the sealing materials 50A and 50B (see FIG.
(See 0), there is an advantage that the excessive consumption of the solidifying material is avoided and the fluidity is easily adjusted.
The mud-water shield machine has been described above as an example, but the present invention can be effectively applied to a sealed shield machine such as an earth pressure shield machine and a mud earth pressure shield machine.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a shield machine in which a cutter disk retracts.

FIG. 2 is an explanatory view showing a state in which the cutter disk of the other shield machine is fitted into the skin plate of the one shield machine.

FIG. 3 is a state diagram in which two shield excavators facing each other toward a tunnel junction are excavating a tunnel.

FIG. 4 is a state diagram in which the leading shield machine is stopped and the trailing shield machine is moving forward toward the tunnel junction.

FIG. 5 is a state diagram in which the cutter disk of the leading shield machine is retracted and the cutter disk of the trailing shield machine is fitted in the leading machine.

FIG. 6 is a state diagram in which a solidifying material is injected.

FIG. 7 is a state diagram in which the tip of the cutter disk of the trailing shield machine is slightly overlapped with the skin plate of the leading shield machine.

FIG. 8 is a state diagram in which various devices and members inside the machine are disassembled and removed, leaving the skin plates of the two shield machines.

FIG. 9 is a state diagram in which both tunnels are joined at a joining portion.

FIG. 10 is an enlarged view of a state in which a solidifying material is injected into a gap between opposed skin plates.

FIG. 11 is a vertical cross-sectional view of a different trailing shield machine.

[Explanation of symbols]

1, 1A, 1B ... Cutter disk, 2 ... Shield body,
9 ... Bearing stand, 10 ... Rotation support, 13 ... Drive source, 14 ...
Support arm 21,21A ... Shield machine (leading shield machine), 21B, 41B ... Shield machine (rear shield machine), 23,23A, 23B ... Skin plate, 24,24A, 24B ... Side over cutter Two
5 ... Retracting means (retracting jack), M ... Tunnel junction,
N ... axis.

Claims (2)

[Claims] 1. A shield machine having a cutter disk for excavating a natural ground at a front portion of a cylindrical skin plate, the bearing being provided inside the skin plate so as to be displaceable in an axial direction of the shield body. A rotatable support body supported by a table and rotatable, a cutter disk integrated with the rotatable support body through a support arm on the front side of the rotatable support body, and an outer surface of the skin plate attached to the cutter disk. A side overcutter capable of projecting to the outside of the diameter, a drive source for rotating the cutter disk via the rotary support, a bearing base, a rotary support, a cutter disk and a drive source in the axial direction of the shield body. And a retracting unit that can be retracted into the skin plate and retracted into the skin plate. 2. A shield excavator having a side over cutter attached to a cutter disk that can be projected to the outside of the outer diameter of the skin plate, and is excavated so as to face each other toward the tunnel junction. The side over cutter of one shield machine that has reached the tunnel junction is retracted, then the cutter disk is retracted into the skin plate, and the other shield machine is advanced to reduce the side over cutter. Then, the tunnel joining method is characterized in that only the cutter disk is fitted into the skin plate of the one shield excavator facing the other.