JPH1018781A - Tunnel excavator and excavating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an excavator body of a tunnel excavator from being easily retracted so as to enhance the working efficiency of excavation and to lower the cost. SOLUTION: A rotatable cutter 13 is mounted in the front part of a front barrel 11 which is provided with a front gripper 29 which is made into press contact with the inner wall surface of an existing tunnel so as to be positionally held. A rear gripper 29 which is made into press contact with the inner wall surface of the existing tunnel so as to be positionally held, is provided in a rear barrel 2, and a parallel link mechanism 28 is laid between the front barrel 11 and the rear barrel 12. Further, a retraction preventing member 51 is fixed to the existing tunnel by lock bolts 52 in the rear part of the rear barrel 12 as viewed in the excavating direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel excavator and a tunnel excavation method, and more particularly to a tunnel boring machine (T) for excavating rock or the like to construct a tunnel.
BM).

[0002]

2. Description of the Related Art FIG. 7 shows an outline of a conventional tunnel excavator, and FIG. 8 shows an outline of a steel material for preventing backward movement.

As shown in FIG. 7, in a conventional tunnel excavator, a front body 101, a middle body 102, and a rear body 103 each having a cylindrical shape are movably fitted in the axial direction with respect to each other. A cutter head 104 is rotatably mounted at the front of 101.
This cutter head 104 has a large number of cutters 105 for digging rock in the front and an opening 1 for taking in shear.
06 is formed, and can be driven and rotated by a cutter turning motor (not shown) mounted in the front body 101. Further, a pair of front grippers 107 for holding the position of the front body 101 in pressure contact with the inner wall surface of the excavated tunnel is mounted on the front body 101, and can be driven by a hydraulic jack (not shown). On the other hand, a pair of rear grippers 108 are attached to the rear body 103 to press against the inner wall surface of the tunnel formed by excavation and hold the rear body 103 while receiving the excavation reaction force, and can be driven by a hydraulic jack (not shown). I have. Further, between the front trunk 101 and the rear trunk 103, a plurality of thrust jacks (not shown) are erected,
A plurality of connecting jacks (not shown) are provided between the front trunk 101 and the middle trunk 102.

Accordingly, when a plurality of thrust jacks are extended while rotating the cutter head 104 while the rear body 103 is held in position by pressing the rear gripper 108 against the inner wall surface of the existing tunnel, a large number of cutters 105 are formed. The front trunk 101 moves forward while excavating the ground in front. When the thrust jack extends a predetermined stroke, the front gripper 107 is pressed against the inner wall surface of the existing tunnel to hold the position of the front trunk 101, while the rear gripper 108 releases the pressure contact of the inner wall surface of the existing tunnel. In this state, when the plurality of thrust jacks are contracted, the rear trunk 103 is pulled toward the front trunk 101 and moves forward. Thereafter, as described above, while holding the position of the rear trunk 103 by the rear gripper 108, releasing the position of the front trunk 101 by the front gripper 107, and extending the plurality of thrust jacks while rotating the cutter head 104. The rock is excavated by a number of cutters 105 to move forward. In addition, cutter 1
The shear generated by the excavation of the ground by 05 is taken into the front body 101 through the opening 106 of the cutter head 104, conveyed backward by a belt conveyor (not shown), and discharged to the outside. The tunnel is built by repeating this.

When a tunnel is excavated and formed by a tunnel excavator, the ground to be excavated is soft,
If the cutter head 104 cannot obtain sufficient pressing force or if the weight of the machine is supported by each gripper in addition to the thrust force when excavating a slope with a large uphill, the gripper force is insufficient and the excavator body May retreat.

[0006] In such a case, conventionally, the steel 20
1 was used to prevent the tunnel excavator from retracting. That is, as shown in FIGS. 7 and 8, a large number of anti-backup steel materials 201 are laid under the inner wall surface of the existing tunnel, and the anti-backup steel materials 201 are fixed by lock bolts 202.
At this time, the mortar is cast between the anti-backup steel materials 201 and fixed to the inner wall surface of the existing tunnel, thereby increasing the adhesion. If there is a risk of collapse at the upper part of the inner wall surface of the existing tunnel, attach a support and fix it with mortar or rock bolts. And the rear trunk of the tunnel excavator
The retraction is prevented by abutting the rear end portion 103 on the steel material 201 preventing retraction.

[0007]

When the ground is excavated by the tunnel excavator to form a tunnel, if the excavated ground is a bedrock layer and there is no danger of collapse, the existing tunnel is excavated. This is done by assembling a ring beam on the inner wall of the car or spraying cement. Then, as described above, when the ground to be excavated is soft and the cutter head 104 cannot obtain a sufficient pressing force, the steel material 201 for preventing retreat is fixed or a support is assembled. However, this steel
201 is a sheet metal welding structure, and if it is to be laid on the inner wall surface of the existing tunnel, the cost will be enormous,
Further, there is a problem that a robot for laying is required, so that the workability is poor and the cost is high.

Further, unless a large number of the retraction preventing steel members 201 are fixed to the inner wall surface of the existing tunnel, the retreat of the tunnel excavator cannot be reliably prevented, and the soft ground in the tunnel excavation direction is predicted in advance. It is necessary to start fixing the anti-backup steel material 201 from the near side. However, it is difficult to predict the geology to be excavated in advance, it is time-consuming, and its reliability is not sufficient.

The present invention has been made to solve such a problem, and a tunnel excavator and a tunnel excavation method for easily preventing retraction of an excavator body to improve excavation work efficiency and reduce costs. The purpose is to provide.

[0010]

According to the present invention, there is provided a tunnel excavator having a tubular excavator body and a cutter head rotatably mounted on a front portion of the excavator body. Cutter head driving means for driving and rotating the cutter head, a front support member disposed on the excavator body and pressed against an inner wall surface of an existing tunnel to hold the position of the excavator body; A rear support that receives the excavation reaction force by being held behind the main body by pressing against the inner wall surface of the existing tunnel, and a propulsion means erected between the excavator main body and the rear support. And an anti-retreat member fixed to an existing tunnel at the rear of the excavator body in the excavation direction.

Therefore, when excavating a tunnel, while the rear support is pressed against the inner wall surface of the existing tunnel and held at the position, the cutter head is driven and rotated by the cutter head driving means, and the propulsion means is used to drive the rear support to the rear support. On the other hand, when the excavator body is advanced, the ground in front of the excavator is excavated by the rotationally driven cutter head, and a tunnel is formed. Along with the excavator body excavation, a backward prevention member is mounted on the existing tunnel behind the excavator. Therefore, even when the ground is soft and the rear support cannot receive the excavation reaction force sufficiently, the rear end of the excavator main body abuts on the existing anti-backup member, so that the excavator main body has sufficient Excavation reaction force is obtained and the vehicle can move forward reliably.

Further, in the tunnel excavator of the present invention,
The receding prevention member has a space inside, and the space is used as a ventilation duct, a space for excavated earth and sand discharge, or a cable duct.

Therefore, ventilation ducts, excavated sediment discharge pipes,
There is no need to provide separate pipes for cable ducts, etc., and effective use in existing tunnels can be achieved.

Further, in the tunnel excavation method of the present invention, the propulsion means provided between the excavator body and the rear support is operated while the rear support is pressed against the inner wall surface of the existing tunnel. With the rear support receiving the excavation reaction force,
While advancing the excavator body, excavating the ground in front by driving and rotating a cutter head mounted on the front part of the excavator body by cutter head driving means,
A retraction preventing member is attached to an existing tunnel at a rear portion of the excavator body in the excavation direction.

Therefore, even if the ground becomes soft and the rear support cannot receive the excavation reaction force sufficiently,
The rear end of the excavator body abuts on the existing anti-retraction member, so that the excavator body can reliably move forward with a sufficient excavation reaction force.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic sectional view of a tunnel boring machine as a tunnel excavator according to an embodiment of the present invention.
2 to 5 show a main part of the tunnel boring machine. FIG. 2 is a front view of the tunnel boring machine, FIG. 3 is a cross section taken along line III-III of FIG. 1, and FIG. 4 is a line IV-IV of FIG.
FIG. 5 shows a cross section taken along line VV of FIG. 1, and FIG. 6 shows a cross section taken along line VI-VI of FIG.

In the tunnel boring machine (hereinafter, referred to as TBM) of the present embodiment, as shown in FIGS. 1 to 6, the excavator body is constituted by a front body 11 and a rear body 12 each having a cylindrical shape. A front outer periphery of the rear trunk 12 is movably fitted to a rear inner periphery of the front trunk 11. The cutter head 13 has a cutter drum 14 fixed to the rear,
Since the cutter drum 14 is supported by the bearing 15 of the front body 11, the cutter head 13 is rotatably mounted on the front part of the front body 11. The cutter head 13 is provided with a roller cutter 16 for shearing and breaking rock mass in front thereof.
Are fixed, and a cutter bucket 17 for taking in the destructed shear is fixed. This cutter head 1
A ring gear 18 having external teeth is integrally fixed to a rear portion of the cutter drum 14 integrated with the cutter 3, while an electric or hydraulic cutter turning motor 19 is fixed to the front body 11. Nineteen drive gears 20 mesh with the ring gear 18.

Further, a bulkhead 21 is formed on the front body 11 to separate the cutter head 13 from the cutter turning motor 19 so that the shear generated by the excavation does not enter the inside. This bulkhead 21
Is formed between them. And
A hopper 23 that accumulates shears in the chamber 22 is fixedly disposed on the bulkhead 21.
A belt conveyor 24 for discharging the waste accumulated in the hopper 23 to the outside is attached to a lower portion of the front hopper 23. The belt conveyor 24 extends rearward in the front trunk 11 and the rear trunk 12.

The device for discharging the shear by the belt conveyor 24 may be a device for discharging the shear to the outside by a jet pump. For example, a water supply pipe for supplying water to the jet pump and a water supply are provided in the excavator body. It is also possible to provide a discharge pipe for discharging the collected water and waste, suck the waste accumulated in the hopper 23 into the discharge pipe by the jet water from the jet pump, and discharge the waste through this discharge pipe. .

Accordingly, when the cutter rotating motor 19 is driven to rotate the drive gear 20, the ring gear 18 meshing with the drive gear 20 is rotated, the cutter head 13 integrated with the ring gear 18 is rotated, and the roller cutter 16 is rocked. Can be excavated by shear fracture. Then, the cutter bucket 17 takes the shear into the chamber 22 and drops it into the hopper 23, and the shear that has fallen and accumulated in the hopper 23 is discharged to the outside by the belt conveyor 24.

Further, twelve thrust jacks 25 as propulsion means are provided between the front trunk 11 and the rear trunk 12. The thrust jack 25 is operated to expand and contract by supplying and discharging hydraulic pressure.
Swingably supported by a ball bearing 26 fixed to the
The rod tip is swingably supported by a ball bearing 27 fixed to the rear barrel 12. The thrust jacks 25 are arranged adjacent to each other. For example, one of the thrust jacks adjacent to each other is inclined in one circumferential direction of the cutter head 13, and the other thrust jack is inclined in the circumferential direction of the cutter head 13. The parallel link mechanism 28 is arranged in a truss shape as a whole by being inclined to the other side.
Is composed.

Since the front trunk 11 and the rear trunk 12 are connected by the parallel link mechanism 28 in this manner, a frame or the like for connecting the respective trunks becomes unnecessary. In this embodiment, the parallel link mechanism 28 is connected to twelve thrust jacks 25.
However, the present invention is not limited to this, and the number thereof may be appropriately set according to the size of the tunnel boring machine and the like.

Therefore, by extending and contracting each drive rod of each thrust jack 25 of the parallel link mechanism 28, the relative position between the front body 11 and the rear body 12 can be changed, and the front body 11 and the rear body 12 can be changed. By disabling one of them, the other of the front trunk 11 and the rear trunk 12 can be advanced. Further, by changing each operation stroke of each thrust jack 25 of the parallel link mechanism 28, the front trunk 11 having the cutter head 13 can be bent with respect to the rear trunk 12, and the excavation direction can be changed.

As shown in FIGS. 1 and 3, a front gripper 29 is mounted on the front trunk 11. The four gripper shoes 30 of the front gripper 29 are mounted on the front body 11 at substantially equal intervals in the circumferential direction so as to freely protrude and retract, and can be driven in a radial direction by a built-in hydraulic jack 31. Therefore, when this hydraulic jack 31 is driven to project each gripper shoe 30 in the radial direction,
From the position where the gripper shoe 30 is stored in the front body 11, the gripper shoe 30 is pressed against the excavated inner wall surface of the tunnel and
Can be moved to a position for holding.

On the other hand, a rear gripper 32 is mounted on the rear trunk 12, as shown in FIGS. The two gripper shoes 33 of the rear gripper 32 are attached to the rear trunk 12 at substantially equal intervals in the circumferential direction so as to be able to protrude and retract.
It can be driven in the radial direction by a built-in hydraulic jack 34. Accordingly, when the hydraulic jacks 34 are driven to project the respective gripper shoes 33 in the radial direction, the gripper shoes 33 are pressed against the excavated and formed inner wall surface of the tunnel from the position where the gripper shoes 33 are accommodated in the rear body 12. 12 can be moved to a position for holding the same.

As shown in FIG. 1 and FIG.
Numerous steel pipes 51 are provided in the existing tunnel behind 2 as anti-backup members. This steel pipe 51 is attached along the inner wall surface of the existing tunnel, and the lock bolt 5
The steel pipes 51 are provided at four locations in the circumferential direction of the inner wall surface of the tunnel in the above-described tunnel having a circular cross section. And the excavation of TBM,
The connection is made continuously in the longitudinal direction as the tunnel is excavated. The steel pipe 51 is loaded and assembled, and the lock bolt 5
The fixing of 2 and the like are performed by a robot (not shown).

On the other hand, a pre-string 35 is attached to the rear part of the rear trunk 12, and the rear end face of the pre-string 35 of the rear trunk 12 is normally in contact with the tip of the steel pipe 51 fixed to the existing tunnel. I have.

Here, a tunnel excavation method using the above-described tunnel boring machine of the present embodiment will be described.

As shown in FIG. 1, the front gripper 29
By contracting the hydraulic jack 31 of the front body 11 and retracting each gripper shoe 30 and storing it in the front body 11,
Is movable, the hydraulic jack 34 of the rear gripper 32 is extended, each gripper shoe 33 is pushed out, and the outer peripheral surface is pressed against the inner wall surface of the excavated tunnel to hold the rear trunk 12 immovably. In this state, when the thrust jacks 25 of the parallel link mechanism 28 are extended while driving the cutter turning motor 19 to rotate the cutter head 13, the rear gripper 32 receives the excavation reaction force, so that the cutter head 13 and the front body 11 are received. 13 moves forward, and the roller cutter 16 of the revolving cutter head 13 shear-breaks the rock and excavates the rock. At this time, by changing each operation stroke of each thrust jack 25, the front trunk 11 bends with respect to the rear trunk 12, and the direction of the cutter head 13 can be changed to change the tunnel excavation direction.

When each of the thrust jacks 25 is extended by a predetermined stroke, the drive of the thrust jacks 25 is stopped, the hydraulic jacks 31 of the front grippers 29 are extended, and the respective gripper shoes 30 are pushed out to excavate the outer peripheral surface. By pressing against the inner wall of the tunnel,
1 is held immovable, while the hydraulic jack 34 of the rear gripper 32 is contracted and each gripper shoe 33 is retracted and housed in the rear body 12, thereby making the rear body 12 movable. In this state, by contracting each thrust jack 25 of the parallel link mechanism 28, the rear trunk 12 is drawn toward the front trunk 11 and moved forward, so that both approaches.

When each of the thrust jacks 25 is contracted by a predetermined stroke, the driving of the thrust jacks 25 is stopped, and the hydraulic jacks 3 of the rear gripper 32 are again stopped.
4, each gripper shoe 33 is pressed against the inner wall surface of the tunnel to hold the rear body 12, while each hydraulic jack 31 of the front gripper 29 is contracted to press the inner wall surface of the tunnel by each gripper shoe 31. To release. Then, the cutter head 13 is driven by the cutter turning motor 19.
The front body 11 and the cutter head 13 are advanced with respect to the rear body 12 by extending the respective thrust jacks 25 of the parallel link mechanism 28 while rotating the. Then
The cutter head 13 that is driven to rotate is pressed against the front rock, and the roller cutter 16 breaks the rock. The tunnel is excavated by repeating this operation.

Then, the cutter head 1 that is driven to rotate is
The shear generated by rock excavation of the third roller cutter 15 is taken into the chamber 22 by the cutter bucket 17 and falls into the hopper 23. The waste that has fallen and accumulated in the hopper 23 is discharged to the outside by the belt conveyor 24.

As described above, when the tunnel is excavated and formed by the TBM, when the excavated ground is hard, the gripping force of the rear gripper 32 of the rear gripper 32 is pressed against the inner wall surface of the tunnel, so that the holding force of the rear body 12 becomes sufficient. When each thrust jack 25 of the parallel link mechanism 28 is extended, the front trunk 11 can move forward because the rear trunk 12 receives the excavation reaction force. However, when the excavation ground is soft, even if each gripper shoe 34 of the rear gripper 32 is pressed against the inner wall surface of the tunnel, the holding force of the rear trunk 12 cannot be sufficiently secured, and each thrust jack 25 is When it is extended, the rear trunk 12 retreats without receiving the excavation reaction force. Therefore, in this embodiment, at this time, the steel tube 51 attached to the inner wall surface of the existing tunnel prevents the front trunk 11 and the rear trunk 12 from retreating.

That is, with the excavating operation of the front trunk 11 and the rear trunk 12, the robot (not shown) attaches the steel pipe 51 carried into the existing tunnel along its inner wall surface, fixes it with the lock bolt 52, and fixes it in the longitudinal direction. Are connected continuously. Therefore, the pre-string 35 attached to the rear part of the rear trunk 12 is in contact with the tip of the steel pipe 51 attached thereto. When each thrust jack 25 is extended with the gripper shoe 34 of the rear gripper 32 pressed against the inner wall surface of the tunnel, even if the excavation ground is soft, the rear trunk 12 can receive the excavation reaction force by the steel pipe 51, Body 1
1 can surely excavate without retreating.

As described above, at the time of excavation of the TBM, the steel pipe 51 is attached along the inner wall surface of the existing tunnel so that the lock bolt 5
2 and is connected by a large number, and since the pre-string 35 at the rear of the rear body 12 is in contact with the steel pipe 51, the rear body is connected to the soft gripping ground by the rear gripper 3.
Even if a sufficient holding force cannot be secured by 2, the cutter head 13 can excavate the ground in front and excavate a tunnel continuously without the rear trunk 12 being retracted by the steel pipe 51.

In each of the embodiments described above, the tunnel excavator of the present invention has been described using a tunnel boring machine for crushing rock and excavating a tunnel.
The present invention is not limited to this type of excavator, and can also be applied to a shield excavator that excavates soft and moist ground, and as a matter of course, has the same effect as described above. Can be. Further, although a parallel link mechanism in which a plurality of thrust jacks are arranged in a truss shape is used as the propulsion means, a propulsion mechanism in which a plurality of thrust jacks are arranged substantially in parallel may be used.

[0038]

As described above in detail with reference to the embodiments, according to the tunnel excavator of the present invention, a rotatable cutter head is mounted at the front of a cylindrical excavator body, and A front support that presses against and holds the inner wall surface of the existing tunnel on the body of the existing tunnel, and a rear support that is located behind the body of the excavator and presses against and holds the position on the inner wall of the existing tunnel to receive the excavation reaction force Along with the body, the propulsion means was erected between the excavator body and the rear support, and the anti-backup member was fixed to the existing tunnel at the rear of the excavator body in the digging direction, so that the ground became soft. Even if the rear support cannot sufficiently receive the excavation reaction force, the anti-backup member can prevent the excavator body from retreating, and as a result, the excavation work efficiency can be improved and the cost can be improved. Low It can be achieved.

According to the tunnel excavator of the present invention,
A space is provided inside the anti-retraction member, and this space is used as a ventilation duct or a space for excavated sediment discharge or a cable duct. There is no need to provide separate piping for such purposes, and the existing tunnel can be effectively used.

According to the tunnel excavation method of the present invention, the propulsion means provided between the excavator body and the rear support is operated while the rear support is pressed against the inner wall surface of the existing tunnel. While the excavator body is moving forward, the cutter head is driven and rotated to excavate the ground in front of the excavator while the rear support receives the excavation reaction force. Since the members are mounted, the excavator body can be easily prevented from retreating, and the excavation work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a tunnel boring machine as a tunnel excavator according to an embodiment of the present invention.

FIG. 2 is a front view of a tunnel boring machine.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 1;

FIG. 5 is a sectional view taken along line VV of FIG. 1;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 1;

FIG. 7 is a schematic view of a conventional tunnel excavator.

FIG. 8 is a schematic view of an anti-backup steel material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Front trunk (excavator main body) 12 Rear trunk (excavator main body) 13 Cutter head 16 Roller cutter 19 Cutter turning motor (Cutter head driving means) 23 Hopper 24 Belt conveyor 25 Thrust jack 28 Parallel link mechanism (Propulsion means) 29 Front Gripper (front support) 32 Rear gripper (rear support) 51 Steel pipe (retraction preventing member) 52 Lock bolt

Claims (3)

[Claims] An excavator body having a cylindrical shape, a cutter head rotatably mounted on a front portion of the excavator body, cutter head driving means for driving and rotating the cutter head, A front support that is disposed and pressed against the inner wall surface of the existing tunnel to hold the position of the excavator body, and that is positioned behind the main body of the excavator and pressed against the inner wall surface of the existing tunnel to hold the position. A rear support for receiving the excavation reaction force, a propulsion means erected between the excavator body and the rear support, and a retraction preventing member fixed to an existing tunnel at the rear of the excavator body in the digging direction. A tunnel excavator, comprising: 2. The tunnel excavator according to claim 1, wherein the anti-retreat member has a space inside, and the space is a ventilation duct, a space for excavated earth and sand, or a cable duct. A tunnel excavator characterized by being used. 3. The excavator body and the propulsion means installed between the excavator body and the rear support are actuated in a state where the rear support is pressed against the inner wall surface of the existing tunnel. In the received state, while the excavator body is moving forward, the cutter head mounted on the front part of the excavator body is driven and rotated by cutter head driving means to excavate the ground in front, and the excavator body is A tunnel excavation method comprising: mounting an anti-backup member on an existing tunnel at a rear portion in the excavation direction.