JP2000064769A - Magnifying shield machine - Google Patents

Abstract

(57) [Abstract] [Problem] To efficiently construct a primary tunnel and widen a tunnel with one tunnel excavator, thereby shortening the construction period and reducing the construction cost. SOLUTION: A first excavator 2 having a first cutter head 4 at a front end thereof, and a second cutter incorporated in a main body of the first excavator 2 and reciprocally swinging at a front end within a predetermined angle range. The second excavator 3 having the head 11 and the hydraulic jack 16 for causing the second excavator 3 to protrude and retract from the main body of the first excavator 2 in a direction orthogonal to the excavation direction are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an enlarged shield machine capable of excavating a required section of a tunnel with a single machine.

[0002]

2. Description of the Related Art Generally, in tunnel construction work, a tunnel excavator having a disk-shaped cutter head in front of a cylindrical skin plate is used, and the skin plate is excavated while rotating the cutter head. It is supposed to excavate a tunnel of approximately the same diameter.

By the way, recently, along with the expansion of the use range of the tunnel, for example, when installing a subway station, etc., it becomes necessary to excavate a required portion of the circular cross-section tunnel into, for example, an elliptical cross-section. There is. In such a case, conventionally, by using an enlarged shield excavator that digs in a ring shape along the outer peripheral surface of the primary segment while dismantling and removing the lining primary segment, A construction method is adopted so as to build a secondary segment.

However, in such a construction method, the work is extremely wide due to the reasons that the widening work is limited after the construction of the primary tunnel, the ground improvement is required when the starting base of the expanded shield machine is constructed, and the like. There is a problem that it is inefficient.

In order to deal with such a problem, in JP-A-58-213996, a shield is provided on the outer peripheral side of a cylindrical shield frame, and the shield is moved in the radial direction. A shield machine has been proposed in which the diameter of the frame is expanded and the excavation section is made variable by projecting the overcutter from the cutter face plate.

Another prior art related to the present invention is disclosed in Japanese Patent Application Laid-Open No. 10-77781. In this publication, for excavating a tunnel used as a subway, for example, the first excavator body is advanced while drivingly rotating a circular first cutter head,
And the segments are assembled in a ring shape to construct a first tunnel, while the second excavator body is advanced while reciprocally swinging the non-circular second cutter head, and does not contact the ring-shaped segment. A tunnel excavator has been proposed in which a segment is assembled to a part to construct a second tunnel.

[0007]

However, in the former publication (Japanese Patent Laid-Open No. 58-213996), the front face of the cutter head in the widening section and the ground in the radial direction are excavated only by the overcutter. Due to this structure, there is a problem that the efficiency of excavation work in this widening section cannot be avoided. Further, in the one described in this publication, in order to excavate an elliptical cross section, it is necessary to control the protrusion amount of the overcutter according to the rotation angle of the cutter face plate, and not only the mechanism is complicated but also the overcutter There is also a problem in that a separate control device for taking in and out is required and the device configuration becomes complicated.

The latter publication cited as a prior art related to the present application (Japanese Patent Laid-Open No. 10-77781) discloses an irregular cross-section tunnel having a shape in which a first tunnel and a second tunnel are connected. It is intended for excavation and cannot be applied to the use of forming a widened portion in the middle of an excavation section as in the present invention.

The present invention has been made in order to solve such a problem, and one tunnel excavator can efficiently construct a primary tunnel and perform widening work.
It is an object of the present invention to provide an expanded shield machine that can shorten the construction period and the construction cost.

[0010]

In order to achieve the above object, an enlarged shield machine according to the present invention comprises: (a) a first machine having a first cutter head at its front end; (b) A second excavator which is built in the main body of the first excavator and has a second cutter head at the front end that is reciprocally rocked within a predetermined angle range; and (c) the second excavator is the first excavator. It is characterized in that it comprises a retracting means for retracting from the main body in the direction orthogonal to the excavation direction.

In the enlarged shield excavator of the present invention, when excavating a normal primary tunnel of circular cross section, the second excavator is housed in the first excavator main body, and in this state, the first excavator The circular cross section tunnel is excavated by rotating the first cutter head at the front end. Further, when approaching the widening construction section during excavation of this primary tunnel, the second excavator is pushed out from the side portion of the first excavator main body by operating the retracting means, and the portion of the projecting front face of the second excavator The earth and sand are excavated by reciprocally swinging the second cutter head at the front end of the second excavator. Thus
In the widening work section, the ground excavation is performed by driving both the first and second cutter heads to excavate a tunnel having an irregular cross section such as an oval cross section. In addition, when this widening work section is finished and it returns to excavation of the circular section tunnel again,
The second excavator, which also projects by the operation of the retracting means, is housed in the first excavator body. According to the present invention, the second excavator housed in the first excavator body is
Since the excavation of the primary tunnel construction section and the widening construction section can be performed by one excavator by the operation of appearing and retracting to the side of the excavator main body, the construction period can be shortened, and at the time of widening and contracting it. Since no ground improvement is required, the construction cost can be reduced. Further, since the ground is excavated by the second cutter head at the front end of the second excavator in this widening work section, it is possible to avoid the occurrence of a situation in which the excavation work efficiency decreases in this widening work section. it can. Further, since the width expansion and contraction can be performed at any place and section, it can be said that the expansion shield machine has a wide application range.

In the present invention, the tail seal of the first machine and the tail seal of the second machine are the second seal.
It is preferable that they are provided so as to overlap each other in the protruding / retracting direction within the range of the protruding / retracting length of the excavator. By adopting such a configuration, even if the second excavator protrudes to the side of the first excavator main body, the tail seals of both excavators are in a state of overlapping each other. The sealing action of the tail portion is not impaired.

In the present invention, one of the first machine and the second machine is provided with an overcutter device for excavating the ground around the protrusion prior to the protrusion of the second machine. Is preferred. By doing so, when the second excavator is protruding, it is possible to excavate the ground on the side by the overcutter device and secure a space for the protrusion of the second excavator.

Further, between the outer peripheral required portion of the second excavator and the inner peripheral portion of the first excavator facing the outer peripheral required portion, a seal member that slides when the second excavator protrudes is provided. preferable. Thereby, even if the second excavator is operated to retract from the main body of the first excavator, it is possible to reliably prevent the sediment and water from entering the machine.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a specific embodiment of an enlarged shield machine according to the present invention will be described with reference to the drawings.

FIG. 1 is an overall schematic perspective view of an enlarged shield machine according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 is a sectional view taken along line BB of FIG. is there.

The enlarged shield machine 1 of this embodiment is the first
It is composed of the excavator 2 and a second excavator 3 which is built in the main body of the first excavator 2 and is capable of appearing and retracting with respect to the main body of the first excavator 2.

The first machine 2 has a front body portion 5 having a cylindrical skin plate 5a for rotatably supporting a disk-shaped first cutter head 4 at a front end portion, and a front body portion 5 with respect to the front body portion 5. The rear body portion 7 is formed so that a cutout portion 6 for accommodating the second excavator 3 is formed in a part of the side of a cylindrical skin plate 7a which is bendable. Here, this notch 6 is
A first partition wall 8 having a substantially semi-circular shape, the front portion of which is continuous with the skin plate 7a and is arranged in a direction orthogonal to the tunnel axis.
Further, the side portion is formed by the rectangular second partition wall 9 continuous with the first partition wall 8 and arranged in the tunnel axis direction.
Each of them is formed by being partitioned from the internal space of the first excavator 2. The first excavator 2 excavates the natural ground on the front surface by rotationally driving the first cutter head 4 by the cutter head driving motor 10.

On the other hand, in the second excavator 3, a second cutter head 11 having a shape in which a part of a disk is cut out is supported at its front end so as to reciprocally swing, and the second cutter head 11 is hydraulically jacked. Alternatively, the rocking drive mechanism 12 such as a forward / reverse rotation motor is reciprocally rocked within a predetermined angle range to excavate the ground in front of the second cutter head 11. Here, the rotation center axis of the first cutter head 4 of the first excavator 2 and the swing center axis of the second cutter head 11 of the second excavator 3 are made to coincide with each other.
Further, an overcutter 13 is mounted on the outer peripheral portion of the second cutter head 11 so as to be retractable and retractable, and when the second excavator 3 is pushed out to the side of the first excavator 2, the overcutter 13 is used to make a lateral movement. The excavation of the natural ground has been started.

The second excavator 3 has an outer peripheral surface covered with a skin plate 14 having an arcuate surface, and an inner surface side of the rectangular partition wall 15 which is continuous with the skin plate 14 and faces the second partition wall 9. And has a substantially semi-cylindrical shape as a whole. Here, the curvature of the skin plate 14 is made equal to the curvature of the skin plate 7a, so that when the second excavator 3 is housed in the first excavator 2, both skin plates 7a, 14 is designed to have a continuous curved surface without steps.

A hydraulic jack 16 as a retracting means is attached to the second partition wall 9, and the rod tips of these hydraulic jacks 16 are fixed to the partition wall 15 on the side of the second excavator 3 so that the hydraulic jack 16 can operate. The second excavator 3 by expansion and contraction operation
Is capable of appearing and disappearing laterally with respect to the first machine 2.

In order to smoothly move the second excavator 3 in and out, flat plate-shaped slide parts 17 and 18 are provided at the upper end and the lower end of the skin plate 7a. At the position facing the pieces 17 and 18, the slide plate piece 1 which is also flat plate-like on the skin plate 14 is provided.
9 and 20 are provided. In addition, the front end portions of the slide pieces 19 and 20 on the second excavator 3 side are connected to each other,
Further, a continuous piece 21 is provided in front of the second cutter head 11 so as to be continuous with the partition wall 15.
Then, between the slide piece 17 and the slide piece 19,
Between the connecting piece 21 and the first partition wall 8 and the slide piece 1
8 and the slide portion piece 20 are held by the second excavator 3 side so that the seal member 22 (slide portion piece 1
A seal member (not shown) between 7 and 19 and between the slide pieces 18 and 20 is inserted. Thus
Even if the second excavator 3 is retracted laterally with respect to the first excavator 2, dirt, water, etc. are prevented from entering the machine from between the sliding surfaces of the two.

On the other hand, as shown in FIG. 3, in the first excavator 2, the shield jack 23 is arranged along the inner peripheral surface of the skin plate 7a of the rear trunk portion 7, and the second excavator 2 is also provided. 3, the shield jack 24 is arranged along the inner peripheral surface of the skin plate 14.

Further, as shown in FIG. 2, a tongue piece 25 is provided at the rear end of the skin plate 7a of the first excavator 2.
Are integrally molded. This tongue piece 25 is used for the second excavator 3
Is extended so as to cover the rear end face of the second excavator 3 in the direction of emergence and withdrawal within a range equal to or greater than the sliding length (extinguishing length), and a tail seal 26 is attached to the inner peripheral surface thereof. With this configuration, the tail seal 26 of the first excavator 2 overlaps with the tail seal 27 of the second excavator 3 even when the second excavator 3 protrudes laterally from the inside of the first excavator 2. In this state, no gap is formed between the tail seals, so that the first excavator 2 and the second excavator 3
The sealing action of the tail portion of is not impaired.

Expanded shield machine 1 having the above construction
The operation of will be described below.

First, when excavating a normal circular section tunnel, as shown in FIG. 2, with the second excavator 3 housed in the first excavator 2, the cutter head drive motor 10 is housed. When the shield jacks 23 and 24 are extended while the first cutter head 4 is rotationally driven, the first excavator 2 and the second excavator 3 obtain a reaction force in the segment 28 (see FIG. 4) and proceed to the excavation, A standard section (circular section) tunnel is constructed. The second cutter head 11 is not being rocked when excavating the circular section tunnel. Further, the excavated earth and sand taken into the machine by the rotation of the first cutter head 4 is carried out to the rear of the tunnel by a not shown drainage pipe or the like.

Next, when the construction of the widening tunnel is started, the second cutter head 11 is reciprocally rocked by the rocking drive mechanism 12 while the first cutter head 4 is rotationally driven, and the over cutter 13 is projected. Then, the overcutter 13 excavates the ground on the side of the second machine 3,
At the same time, the hydraulic jack 16 is operated in the extension direction so that the second excavator 3 is pushed laterally to the first excavator 2. Also,
In conjunction with these operations, the shield jacks 23 and 24 are extended to advance the first excavator 2 and the second excavator 3. In this way, the second excavator 3 is gradually excavated laterally from the inside of the first excavator 2 by securing the protruding space by excavating the ground on the side by the overcutter 13. In addition, since the ground in front of the second cutter head 11 is excavated by the reciprocating swing of the second cutter head 11 as the second excavator 3 is pushed out, The excavated section on the overhang side will be gradually widened. On the protruding side of the second machine 3, a tapered segment 29 is wound up as shown in FIG. 4 (b).

Then, after the second excavator 3 has protruded by the required amount of protrusion, the overcutter 13 is returned to its original position, and the first cutter head 4 is rotationally driven and the second cutter head 11 is rocked. The dynamic driving excavates a widening tunnel (see FIG. 4A) having an oval cross section. In addition,
When the widening work section ends and the process returns to the excavation of the circular cross-section tunnel again, the hydraulic jack 16 is operated to store the second excavator 3 in the protruding state in the first excavator 2.

In this embodiment, even if the second machine 3 moves to the projecting position, the seal member 22 reliably seals the sliding surface between the first machine 2 and the second machine 3, and The tail seal 26 of the first excavator 2 and the tail seal 27 of the second excavator 3 are arranged so as to overlap each other in the range of the appearance length of the second excavator 3 or more, and the tail portions are also reliably sealed. Therefore, dirt, water, etc. will not enter the plane.

According to the enlarged shield machine 1 of the present embodiment, excavation of the primary tunnel construction section and the widening construction section can be performed by one machine, so that the construction period can be shortened and the construction period can be shortened. Since the ground improvement is not required at the time of widening and reducing, the construction cost can be reduced, and the excavation work in the widening work section can be efficiently performed, which is an excellent effect. Also,
There is also an advantage that this tunnel can be expanded and contracted at any place and section.

In this embodiment, the overcutter for excavating the ground on the side is provided on the second excavator 3 side, but this overcutter may be provided on the first excavator 2 side. You can

[Brief description of drawings]

FIG. 1 is an overall schematic perspective view of an enlarged shield machine according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is an explanatory view showing a segment shape by widening excavation, (a) showing a cross section after widening;
(B) is sectional drawing which shows a widening aspect, (c) is a figure which shows a standard cross section.

[Explanation of symbols]

1 Enlarged shield machine 2 first excavator 3 second excavator 4 1st cutter head 6 notches 8 First partition 9 Second partition 11 Second cutter head 13 Over cutter 15 partitions 16 hydraulic jack (withdrawal means) 17, 18, 19, 20 Slide piece 21 Continuously installed pieces 22 Seal member 25 tongue 26,27 tail seal 28,29 segment

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Norio Mitani             2-3-3 Akasaka, Minato-ku, Tokyo Co., Ltd.             Komatsu Manufacturing Head Office (72) Inventor Mitsuyuki Iwakiri             2-3-3 Akasaka, Minato-ku, Tokyo Co., Ltd.             Komatsu Manufacturing Head Office F term (reference) 2D054 AA05 AB01 AD03 AD20 BA03                       BA25 BB01

Claims (4)

[Claims] 1. A first excavator having a first cutter head at a front end thereof, and (b) a first excavator incorporated in a main body of the first excavator, which is reciprocally rocked at a front end within a predetermined angle range. A second excavator having a second cutter head, and (c) an enlarged shield excavator including a retracting means for retracting the second excavator from the main body of the first excavator in a direction orthogonal to the excavation direction. . 2. The tail seal of the first excavator and the tail seal of the second excavator are provided so as to overlap each other in the protruding / retracting direction of the second excavator within a range of the protruding / retracting length or more. The expanded shield machine according to claim 1. 3. An overcutter device is provided on either one of the first machine and the second machine to excavate the ground around the protrusion prior to the protrusion of the second machine. The expanded shield machine according to 1 or 2. 4. A seal member is provided between an outer peripheral required portion of the second excavator and an inner peripheral portion of the first excavator opposite to the outer peripheral required portion, the seal member sliding when the second excavator protrudes. The expanded shield machine according to any one of claims 1 to 3.