JP3690855B2 - Tunnel excavation method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tunnel excavation method for excavating and forming a tunnel for a small-diameter passage along a subway or the like.
[0002]
[Prior art]
A general shield excavator is configured such that a circular cutter head is rotatably attached to a front portion of a cylindrical excavator body, and a segment erector is attached to a rear portion of the excavator body. Therefore, the excavator body is advanced while the cutter head is swung by the drive motor to excavate the ground to form a tunnel, and the segment is attached to the inner wall surface of the tunnel formed by the segment erector. You can build a tunnel.
[0003]
By the way, there is a tunnel used for subway as a tunnel to be excavated. The tunnel used as this subway usually requires two parallel traveling tunnels for traveling up and down subways. Further, a station is required on the subway, and in order to form this station, it is necessary to connect two independent tunnels with a predetermined interval as described above to form a wide space. Further, a small-diameter tunnel through which the station user passes is required above the station.
[0004]
Conventionally, in the tunnel excavation method used for the subway, the two tunnels as the traveling section of the subway on the upper and lower lines use the above-described two shield excavators, and operate these two shield excavators in order, Two independent tunnels are constructed with a predetermined interval. And the wide space part which forms a station uses three shield excavators, operates these three shield excavators in order, for example, forms a central tunnel with the first shield excavator, A side tunnel is formed by the second shield excavator so that the central tunnel and the tunnel cross section partially overlap, and further, the side shield is formed by the third shield excavator so that the central tunnel and the tunnel cross section partially overlap. A tunnel is constructed by forming a tunnel. Furthermore, a small-diameter tunnel through which a user passes was formed by excavation by an operator by hand dug in the upper part of the central tunnel.
[0005]
[Problems to be solved by the invention]
However, in such a conventional tunnel excavation method, when a small-diameter tunnel through which a user passes is constructed, since the operator forms it by manual digging, the burden on the operator is large and excavation is large. There was a problem that efficiency was not good. Excavation with a small-diameter tunnel excavator is also possible, but excavation along existing tunnels was difficult.
[0006]
The present invention solves such problems, and an object of the present invention is to provide a tunnel excavation method that reduces the burden on the operator and improves the excavation work efficiency.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a tunnel excavation method according to the present invention is a tunnel excavation method for excavating and forming a small-diameter tunnel along a pair of parallel tunnels constructed in a cylindrical shape by a plurality of segments. While driving and rotating a cutter head having a cutter bit attached to the front end portion of the front end, the copy cutter is projected and retracted outward from the cutter head, and the corner cutters provided on both sides of the lower end of the front end are rotated, and the excavation is performed. by promoting machine body, while cutting the outer peripheral surface of the segments forming the pair of existing tunnels excavated tunnel having a predetermined shape cross section, assembled segments on the inner wall surface of the tunnel and the excavation formed, the pair A small-diameter tunnel is constructed above the existing tunnel .
[0008]
Therefore, the ground in front is excavated by the rotating cutter head, copy cutter, and corner cutter. At this time, the outer peripheral surface of the segment that forms an existing tunnel with the ground is cut, and a tunnel having a predetermined cross section is excavated along this segment. Will be.
[0009]
Further, in the tunnel excavation method of the present invention, a guide groove is formed in advance along the direction of excavation at a predetermined position of the segment forming the existing tunnel, and the guide groove is filled with a member that is easy to cut, The cutter head, the copy cutter, or the corner cutter is characterized by constructing a small-diameter tunnel while excavating the filling portion of the segment.
[0010]
Therefore, when excavating with the rotating cutter head, the copy cutter, and the corner cutter, the member filled in the guide groove of the segment advances while cutting, and the excavator body advances along the guide groove to form a small diameter tunnel. .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings.
[0012]
FIG. 1 is a front view of a shield excavator for carrying out a tunnel excavation method according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. Fig. 4 shows an outline of a corner cutter, and Fig. 4 shows a cross section of a tunnel excavated by the shield excavator of this embodiment.
[0013]
As shown in FIGS. 1 and 2, the shield excavator of this embodiment excavates and forms a tunnel used for an underground passage in the upper part of a triple tunnel constructed as a subway. That is, in the shield excavator of the present embodiment, the circular cutter head 12 is rotatably attached to the front portion of the excavator main body 11 having an arcuate upper portion and a rectangular tubular lower portion. A number of cutter bits 14 are fixed to a plurality of spokes 13 that are radially attached to the cutter head 12. A ring gear 15 is fixed to the base end side of the cutter head 12, and a drive motor 16 is attached to the excavator body 11, and the drive gear 17 of the drive motor 16 is a ring gear 15. Are engaged. Accordingly, when the drive motor 16 is driven, the cutter head 12 can be rotationally driven via the drive gear 17 and the ring gear 15.
[0014]
Further, a copy cutter 18 is movably mounted in each spoke 13 of the cutter head 12, and each copy cutter 18 can be moved in and out by a hydraulic cylinder 19. Further, a pair of corner cutters 20 are attached to the lower part of the excavator body 11 so as to be located on both sides of the cutter head 12.
[0015]
In this corner cutter 20, as shown in FIGS. 1 and 3, an inner cylinder 22 is fitted in a support outer cylinder 21 fixed to the excavator body 11 so as to be slidable in the axial direction. A turning hydraulic motor 23 is mounted in the interior 22. A rotating cutter 26 having a cutter bit 25 fixed to the front surface portion and the outer peripheral portion is fixed to the rotating shaft 24 of the rotating hydraulic motor 23. In addition, a gate 27 that can be opened and closed is provided at the front portion of the support outer cylinder 21, and the swing hydraulic motor 23 to which the swing cutter 26 is fixed is moved from the gate 27 by a hydraulic cylinder (not shown) together with the inner cylinder 22. It has become free to appear and disappear.
[0016]
As shown in FIG. 2, a bulk head 28 is provided in the middle part of the excavator body 11, and a chamber chamber 29 is formed between the bulk head 28 and the cutter head 12. A screw conveyor 30 that passes through the bulkhead 28 and has the front facing downward is attached to the central portion of the excavator body 11. Therefore, the earth and sand excavated by the cutter head 12 and the like are taken into the chamber chamber 29 and discharged to the outside by the screw conveyor 30. Further, a plurality of shield jacks 31 are arranged in parallel along the circumferential direction at the rear part of the excavator body 11 and a segment erector 32 for assembling the segment S is disposed. Therefore, when this shield jack 31 is operated and extended rearward in the excavation direction, the excavator body 11 can move forward by the reaction force from the existing segment S constructed on the inner peripheral surface of the excavated tunnel, and the segment erector 32 can mount a new segment S in a space between the existing segment S formed by reducing the shield jack 31.
[0017]
Here, the operation of excavating and forming an underground passage tunnel in the upper part of the triple tunnel already installed by the shield excavator of the present embodiment described above will be described.
[0018]
Note that before the drilling forming an underground passage tunnel, as shown in FIG. 4 has already triplicate tunnel T _1, T _2, T ₃ are formed excavated by the shield excavator (not shown), the tunnel T _1, T ₂ is for traveling on the subway A, and the tunnel T ₃ is for forming the station portion P. In the following, the case where the underground passage tunnel T ₄ is formed above the tunnel T ₃ will be described. .
[0019]
In this case, a segment for constructing the existing tunnels T ₁ and T ₂ is formed of steel, and a guide groove G is formed in advance at a predetermined position along the direction of excavation in this segment. As a member that is easy to cut, a filler such as foamed polystyrene or mortar is filled. Therefore, the shield excavator of this embodiment excavates while cutting the filling portion in the guide groove G of this segment.
[0020]
As shown in FIGS. 1 and 2, when the shield jack 31 is extended while the drive motor 17 is driven to rotate the cutter head 12, the excavator body 12 moves forward due to the reaction force from the existing segment S. A large number of cutter bits 14 excavate the front ground to excavate the tunnel. Then, as the cutter head 12 is rotated, the respective copy cutters 18 are caused to appear and disappear by the respective hydraulic cylinders 19, thereby excavating a portion of the cutter head 12 that cannot be excavated by the cutter bit 14. Further, by rotating the swing cutter 26 by the swing hydraulic motor 23, the cutter bit 25 excavates a portion that cannot be excavated by the cutter bit 14 and the copy cutter 18 of the cutter head 12.
[0021]
That is, the front ground is excavated into an elliptical shape by the rotation of the cutter head 12, the lower sides of the elliptical excavating unit are excavated by the appearance of the copy cutter 18 accompanying the rotation, and the lower part of the elliptical excavating unit is rotated by the rotation of the pair of corner cutters 20. The excavator main body 11 is guided by the guide groove G and propelled while excavating the filler filled in the corners on both sides, that is, the segment guide grooves G for constructing the existing tunnels T ₁ and T _2. To do.
[0022]
Then, by segment erector 32 to the space between the existing segments S which are formed by reducing the shield jacks 31 will insert a new segment S, a tunnel T ₄ is constructed.
[0023]
In addition, when the underground tunnel T ₄ is excavated and formed above the triple tunnels T ₁ , T ₂ , T ₃ and the tunnel T ₃ in this way, the tunnels T ₁ , T ₂ , T ₃ are then joined to the sealing material. Then, the intermediate beams are erected and the contact portions with the tunnels T ₁ , T ₂ , T ₃ are cut and removed so as to communicate with each other to form a triple tunnel.
[0024]
【The invention's effect】
As described above in detail with reference to the embodiments, according to the tunnel excavation method of the present invention, while the cutter head is driven to rotate, the copy cutter is made to appear and disappear from the cutter head and is provided on both sides of the lower part of the front surface. By rotating the corner cutter and propelling the excavator body, a tunnel with a predetermined shape is excavated while cutting the outer peripheral surfaces of the segments that form a pair of existing tunnels. Since a small diameter tunnel is constructed on the upper part of the pair of existing tunnels by assembling the segments, the ground in front is excavated by rotating cutter heads, copy cutters, and corner cutters. The outer peripheral surface of the segment to be formed is cut, and a tunnel with a predetermined shape is cut along this segment. Becomes possible to reduce the burden on the worker multiple-tunnel can be easily excavated formed, it is possible to improve the drilling efficiency.
[0025]
Further, according to the tunnel excavation method of the present invention, a guide groove is formed in advance along the direction of excavation at a predetermined position of the segment forming the existing tunnel, and the guide groove is filled with an easy-to-cut member, and the cutter head or copy Since the cutter and corner cutter were constructed to dig a small diameter tunnel while excavating the filling part of the segment,
During excavation by rotating cutter head, copy cutter, and corner cutter, the member filled in the guide groove of the segment is advanced while cutting, and the excavator body advances appropriately along the guide groove to form a small-diameter tunnel. be able to.
[Brief description of the drawings]
FIG. 1 is a front view of a shield excavator for carrying out a tunnel excavation method according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1 showing the outline of the shield excavator of the present embodiment.
FIG. 3 is a schematic view of a corner cutter.
FIG. 4 is a cross-sectional view of a tunnel excavated and formed by the shield excavator of this example.
[Explanation of symbols]
11 Excavator Main Body 12 Cutter Head 17 Drive Motor 18 Copy Cutter 19 Hydraulic Cylinder 20 Corner Cutter 23 Turning Hydraulic Motor 26 Turning Cutter 30 Screw Conveyor 31 Shield Jack 32 Segment Elector

Claims (2)

In a tunnel excavation method for excavating and forming a small-diameter tunnel along a pair of parallel tunnels constructed in a cylindrical shape by a plurality of segments,
While driving and rotating a cutter head having a cutter bit attached to the front end portion of the excavator body, the copy cutter is projected and retracted outward from the cutter head, and the corner cutters provided on both sides of the lower end of the front end are rotated. By excavating the excavator body, excavating a tunnel having a predetermined shape while cutting the outer peripheral surface of the segment forming the pair of existing tunnels,
A tunnel excavation method comprising assembling a segment to an inner wall surface of a tunnel formed by excavation and constructing a small-diameter tunnel above the pair of existing tunnels . The tunnel excavation method according to claim 1,
A guide groove is formed in advance along the digging direction at a predetermined position of the segment forming the existing tunnel,
The guide groove is filled with a material that is easy to cut,
A tunnel excavation method, wherein the cutter head, the copy cutter, or the corner cutter constructs a small-diameter tunnel while excavating a filling portion of the segment.

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