JP2000179290A - Tunnel excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent fall of earth in the natural ground at the crest. SOLUTION: This excavator includes a front shield part 11 and an intermediate and a rear shield parts 12, 13. The shield parts 11 and 12 are rotatably connected to each other through a bearing. The intermediate shield part 12 and the rear shield part 13 are separably connected to each other. A cutter head 14 is freely rotatably disposed at the tip of the front shield part 11. In the front shield part 11, a front gripper 16 is provided to freely project and retreat toward the excavated natural ground excavated surface 15, and a driving motor 17 for driving the cutter head 14 in rotation is provided. A bag 30 where a fluid is injected at need to be expanded is provided between the outer periphery of the rear shield part 13 and the natural ground excavated surface 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel machine and, more particularly, to a technique for eliminating the inconvenience of this kind of machine against loosening of the ground.

[0002]

2. Description of the Related Art Tunnel boring machines (hereinafter referred to as TB)
Basically, M is a full-section excavator that excavates a rock mass while crushing the rock mass with a roller cutter. Usually, a cutter head equipped with a roller cutter generates a thrust to excavate. It is equipped with a thrust jack and a gripper that contacts the ground to secure the excavation reaction force.

By the way, this type of TBM is roughly classified into an open type and a shield type.
The area around the gripper is covered by the shield,
It protects machinery and equipment from the collapse of the ground after excavation.

[0004] In the shield type TBM, in order to cope with the construction of the curved portion and the expansive ground, the excavation diameter is
The outer diameter of the shield is small, for example, a diameter of 5
m TBM was designed such that a gap of about 10 cm or more was left at the top.

However, the conventional shield type T
BM had the following technical issues.

[0006]

That is, the conventional shield type TBM is designed such that a gap of about 10 cm or more is formed at the top end. There is no function to support and prevent collapse.

For this reason, the collapse of the ground occurs before the TBM passes through the tail, and when the collapse at the top end progresses, the loosening pressure of the TBM increases due to the expansion of the loosened area of the ground, and the propulsion force of the TBM is reduced. Increased by frictional resistance, and in some cases,
It is also conceivable that the TBM is restrained by the ground and cannot be propelled.

Further, when the loosening pressure of the ground increases, for example, a support having a large pressure resistance such as a steel segment is required, and thus the problem spreads to the economy.

The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a tunnel excavator capable of preventing a collapse of a ground at a top end portion. Is to do.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a cylindrical shield and a rotatable rocker at a front end of the shield, which is driven to rotate to excavate the ground. A cutter head, a thrust jack for propulsion provided in the shield part, and a gripper provided in the shield part and abutting against the ground to secure a propulsion reaction force. A bag was provided between the outer periphery of the part and the ground excavation surface to inject fluid and expand as needed. According to the tunnel machine constructed as described above, since a bag is provided between the outer periphery of the shield portion and the ground excavation surface to inject and expand fluid as necessary, the construction or expansion of the curved portion is performed. Even if the outer diameter of the shield part is smaller than the excavation diameter in order to cope with the natural ground, the fluid is injected and the bag is expanded to create a gap between the shield part and the ground excavation surface. Gap can be filled. The bag may be provided in an upper half portion of an outer periphery between the shield part and a ground excavation surface. According to this configuration, it is possible to prevent the collapse of the portion that is easily affected by the collapse of the ground by expanding the bag. The shield portion includes front, middle, and rear shield portions divided into three, and the bag includes a first bag provided in the front and middle shield portions, and a second bag provided in the rear shield portion. A bag, and the first and second bags can be superposed on the outer peripheral side of the rear shield portion. According to this configuration, the technical idea of the present invention can be applied to the divided shield portions. When the first and second bags are located on the fixed side, the internal pressure can be made larger than that on the moving side. According to this configuration, it is possible to more surely prevent the collapse of the ground while securing the smooth excavation of the excavator. As the fluid used for expanding the bag, a gas such as air or a liquid such as water can be adopted.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 show a first embodiment of a tunnel machine according to the present invention.

A tunnel excavator 10 shown in FIG. 1 has a cylindrical front shield portion 11 having both ends opened and a cylindrical shape having both ends opened and the same diameter, and has two independent middle and rear shield portions 12. , 13 are provided.

The shield portions 11 and 12 are rotatably connected to each other via a bearing. The middle shield part 12 and the rear shield part 13 are separably connected.

At the tip of the front shield portion 11, a cutter head 14 having a roller cutter for crushing and excavating the ground is rotatably arranged. Further, in the front shield part 11, a front gripper 16 provided so as to be able to protrude and retract toward the excavated ground excavation surface 15 and a drive motor 17 for rotating the cutter head 14 are provided.

The front gripper 16 is composed of a plurality of pieces arranged at predetermined intervals along the circumferential direction.
A jack for expanding and contracting the gripper plate toward the excavated ground excavation surface 15 is provided, and an electromagnetic relief valve for controlling the pressure of the jack is provided.

The rear shield 13 has a cutter head 1
At the time of excavating the ground at 4, it comes into contact with the ground excavation surface 15,
A main gripper 18 that takes a reaction force by pressing this is provided.

The main gripper 18 includes the rear shield 1
The main grippers 18 extend and contract the gripper plate toward the excavated pit wall side in the same manner as the front gripper 16 at each main gripper 18. A jack is built in, and an electromagnetic relief valve for controlling the pressure of each jack is provided.

On the rear end side in the rear shield portion 13,
Segment 1 installed behind the ground when the ground is bad
9 is provided with a shield jack 20 for propelling the tunnel machine 10 by taking a reaction force, and an erector 21 for assembling the segment 19.

Further, between the middle shield part 12 and the rear shield part 13, a plurality of thrust jacks 22 for propelling the front and middle shield parts 11, 12 forward are provided.

In FIG. 1, the member indicated by reference numeral 23 is a direction control jack provided on the front end side of the thrust jack 22, and the reference numeral 24 is a rolling jack provided on the rear end of the thrust jack 22. .

The basic structure of the tunnel machine 10 as described above is the same as that of this type of conventional machine, but the tunnel machine 10 of the present embodiment is remarkable in the following points. There are features.

That is, in the tunnel machine 10 shown in FIGS. 1 and 2, the shield portions 11, 12, and 13 are provided with respect to the diameter of the cutter head 14 in order to cope with the construction of the curved portion and the expansive ground. Is designed so that a gap is formed between the ground excavation surface 15 and the outer periphery of the shield portions 11, 12, 13.

Therefore, in the case of the present embodiment, a fluid (a gas such as air or a liquid such as water) injected as needed between the outer periphery of the rear shield portion 13 and the ground excavation surface 15. A bag 30 is provided which is expanded by being injected.

The bag 30 is made of, for example, cloth-applied rubber or the like and can withstand digging friction.
The rear shield portion 13 has a length substantially the same as the entire length in the axial direction, and the circumferential direction covers the upper half of the outer periphery between the rear shield portion 13 and the ground excavation surface 15 as shown in FIG. The lower surface is adhesively fixed to the outer peripheral surface of the rear shield portion 13.

An injection hose 32 is connected to the bag 30 and a supply source of a gas such as air or a liquid such as water (not shown) is connected to the injection hose 32.

In the tunnel excavator 10 configured as described above, for example, a fluid is injected into the bag 30 via the injection hose 32 to open the bag 30 before a holiday during which the excavation operation is stopped for a predetermined period. During normal digging work, the bag 30 is reduced without injecting fluid.

By performing such a treatment, the shield portion 1
The gaps between the ground excavation surface 15 and the ground excavation surface 15 can be filled by expanding the bag 30 into which the fluid is injected. Therefore, it is possible to avoid that the ground is loosened and the tunnel excavator 10 cannot be re-excavated or becomes difficult during the holiday period in which the excavation of the tunnel excavator 10 is stopped.

For example, when the ground to be excavated is rich in disintegration, fluid may be injected into the bag 30 through the injection hose 32 to expand the bag 30 even during excavation. it can.

In this manner, even if the pressure is low, the ground can be supported by the bag 30, and the increase in the loose pressure due to the expansion of the loose area due to the collapse of the ground can be suppressed.
The possibility that the tunnel machine 10 is restrained can be reduced.

Further, when the loosening pressure of the ground is suppressed, it is possible to select a supporting means having a small withstand pressure.
In this case, in particular, if the ground is self-supporting even after passing through the tail due to the support effect of the bag 30, for example, it is possible to adopt a low-cost and short construction time shoring method such as spraying mortar, and Considering the effect on the excavation time, the effect is very large.

Further, the advantage of adopting the bag 30 that expands with the fluid is that the ground excavation surface 15 and the shield portions 11, 12,
Even if there is a non-uniform portion between the outer peripheral surface and the outer peripheral surface of the thirteen, it may be possible to support the same pressure.

FIGS. 3 to 6 show a second embodiment of the tunnel machine according to the present invention. The same or corresponding parts as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted. A description thereof will be omitted, and only the characteristic points will be described below.

The tunnel machine 10a shown in these figures
Has front, middle, and rear shield portions 11, 12, and 13, and has a main gripper 18, a thrust jack 22, and the like. The basic configuration is the same as that of the first embodiment.

The front, middle, and rear shield parts 11, 1
First and second bags 30a and 30b which are expanded by injecting a fluid as necessary are provided between the outer peripheral surfaces of the bases 2 and 13 and the ground excavation surface 15 as in the first embodiment. Have been.

The first bag 30a has substantially the same length as the entire length of the front and middle shield portions 11 and 12 in the axial direction, and has a circumferential direction as shown in FIG.
It has a length that covers the upper half of the outer circumference between the ground excavation surfaces 15 and 12 and the lower surface side is adhesively fixed to the outer peripheral surfaces of the front and middle shield portions 11 and 12.

As shown in FIG. 4, the first bag 30a is provided with a notch at a portion where the front gripper 16 protrudes and retracts. The first bag 30a includes an injection hose 32a.
Are connected to each other, and a supply source of a gas such as air or a liquid such as water is connected to the injection hose 32a.

The second bag 30b has substantially the same length as the entire length of the rear shield portion 13 in the axial direction, and the circumferential direction between the rear shield portion 13 and the ground excavation surface 15, as shown in FIG. It has a length that covers the upper half of the outer periphery between the lower and upper surfaces.

The second bag 30b includes an injection hose 32b.
Are connected to each other, and a supply source of a gas such as air or a liquid such as water is connected to the injection hose 32b. The first and second bags 30a and 30b overlap each other on the outer peripheral side of the rear shield portion 13.

In the tunnel machine 10a of the second embodiment having the above-described structure, the first and second bags 30 are also provided.
When the fluid is injected into the a and 30b and expanded, the same operation and effect as those of the first embodiment can be obtained. However, in the case of the second embodiment, the first and second bags are explained as follows. 30
a, 30b can also be controlled.

That is, in the case of this embodiment, FIG.
As schematically shown in (A), a pair of first and second bags 30a and 30b that are inflated by injecting a fluid are expanded on the outer peripheral side of the rear shield portion 13 and the rear end side of the first bag 30a is formed on the second side.
They are mounted so as to ride on the front end side of the pug 30b and overlap each other.

In this case, the first and second bags 30a,
The overlap length of 30b substantially corresponds to the stroke length l for propelling the front and middle shield portions 11, 12 with the thrust jack 22.

When the thrust jack 22 is driven to propel the front and middle shield portions 11 and 12, FIG.
As shown in (B), the rear end side of the first bag 30a covers the gap between the middle shield part 12 and the rear shield part 13 accompanying this propulsion.

Then, as shown in FIG. 6C, when the rear shield portion 13 is pulled, the first and second bags 30a and 30b are again overlapped on the outer peripheral side of the rear shield portion 13, and thereafter the same applies. Operation is repeated.

In this case, in the state shown in FIG.
The rear grip 13 is fixed by projecting the main gripper 18 and bringing its tip into contact with the ground excavation surface 15. In the state shown in FIG. 6 (C), the front gripper 16 is made to protrude, and its front end is brought into contact with the ground excavation surface 15 to fix the front and middle shield portions 11 and 12.

At this time, in the state shown in FIG.
In the state shown in FIG. 6C, the second bags 30b are on the fixed side, respectively, and the first bags 30a are on the fixed side.
In the state shown in FIG. 6B, the first bag 30a is on the moving side, and in the state shown in FIG. 6C, the second bag 30b is on the moving side.

The first and second bags 30a, 30 on the fixed side
0b indicates that when the fluid pressure inside is increased, the ground excavation surface 1
Since the gap between the outer peripheral surface of the shield 5 and the outer peripheral surfaces of the shield portions 11, 12, and 13 is closed with a strong force, the collapse of the ground can be reliably prevented.

However, the first and second bags 3 on the moving side
0a, 30b, the tunnel excavator 1
It hinders promotion of 0a. However, in the case of the present embodiment, the bag is divided into two, so that only the advantageous effects can be obtained while avoiding such inconveniences.

That is, before and during propulsion of the tunnel machine 10a, the fluid pressure of the second bag 30b is increased during propulsion, and during propulsion, the fluid pressure of the first bag 30a is kept low. In this case, the fluid pressure of the second bag 30b is reduced, and the fluid pressure of the first bag 30a is increased.

When such pressure control is performed, the propulsion can be easily performed while reliably preventing the collapse of the ground.

In the above embodiment, the shield part of the tunnel machine is divided into three parts. However, the present invention is not limited to this, and the number of divisions is not limited. In the above embodiment, the grippers 16, 18
And the thrust jack 22 are shielded parts 11 and 1
2 and 13 are illustrated, but the present invention is not limited to this.
As disclosed in Japanese Patent No. 57788, the present invention can be applied to a case where a shield portion is short and a thrust jack is provided outside the shield portion.

[0051]

As described above in detail in the embodiments,
ADVANTAGE OF THE INVENTION According to the tunnel excavator which concerns on this invention, the ground collapse at the top end part can be prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory side sectional view showing a first embodiment of a tunnel machine according to the present invention.

FIG. 2 is a sectional view taken along lines AA and BB in FIG. 1;

FIG. 3 is an explanatory side sectional view showing a second embodiment of the tunnel machine according to the present invention.

FIG. 4 is a sectional view taken along lines CC and DD in FIG. 3;

5 is a sectional view taken along line EE and line FF in FIG. 3;

FIG. 6 is an explanatory diagram when performing pressure control of a bag in the tunnel machine shown in FIG. 3;

[Explanation of symbols]

 10, 10a Tunnel machine 11 Front shield part 12 Middle shield part 13 Rear shield part 14 Cutter head 15 Ground excavation surface 16 Front gripper 17 Drive motor 18 Main gripper 30, 30a, 30b Bag

Claims (5)

[Claims] 1. A cylindrical shield portion, a cutter head rotatably provided at a front end of the shield portion and excavating the ground by being driven to rotate, a thrust jack for propulsion, and a thrust jack. In a tunnel machine having a gripper that secures a propulsion reaction force by contacting, a bag is provided between the outer periphery of the shield part and the ground excavation surface to inject fluid and expand as needed. Characteristic tunnel machine. 2. The tunnel machine according to claim 1, wherein the bag is provided in an upper half portion of an outer periphery between the shield part and a ground excavation surface. 3. The shield part before being divided into three parts,
A first bag provided in the front and middle shield portions; and a second bag provided in the rear shield portion, wherein the first and second bags are provided. The tunnel machine according to claim 1 or 2, wherein a bag is superposed on an outer peripheral side of the rear shield portion. 4. The tunnel machine according to claim 3, wherein when the first and second bags are located on the fixed side, the internal pressure is larger than that on the moving side. 5. The tunnel machine according to claim 1, wherein the fluid comprises a gas such as air or a liquid such as water.