JPH03206290A - Shield excavator - Google Patents

Abstract

PURPOSE:To increase the size of a tunnel as existing equipment is jointly used by building an inner shell to build an inner pipe wall for shielding the existing embedded pipe side and the machine body side to a shield frame formed along an existing embedded pipe. CONSTITUTION:A shield excavator comprising a shield frame 23 having a cutter 22 for excavating the outer periphery of an exhausting segment 21 being the existing embedded pipe of a jointly used shield tunnel and an inner shell 24 mounted thereon is set concentrically to the segment 21. The outer periphery of the segment 21 is excavated, a new segment 29 is assembled by means of an erector 5, and simultaneously with the assembly of the new segment, a temporary segment 31 is assembled in a position in front of the rear end of the inner shell 24 by means of an erector 30. Further, a gap between the inner shell 24 and the segment 21 is sealed to shut off the interior of the segment 29 from underground water and sludge, and the size of a tunnel is increased without exercising an influence on an existing tunnel.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a shield excavator that excavates a tunnel and sequentially assembles segments to line the tunnel.

[Conventional technologyAmong the shield excavators that excavate tunnels using the co-shield method, the muddy shield excavator is known as one that stabilizes the face and discharges excavated soil by circulating muddy water. As shown in Figure 3, conventionally this type of shield excavator is
A cutter 1 that rotates to excavate the ground, a shield frame 3 that rotatably supports the cutter 1 and is separated from the face by a distance u2, and an erector 5 that assembles the segments 4.
It is mainly composed of a mud feeding pipe 6 and a mud draining pipe 7 for supplying and circulating mud water to the face.

Using the thrust of the shield jack 'r8 and the rotational force of the drive motor 9 provided on the shield frame 3, a tunnel of a predetermined hole diameter is excavated, and each time the width of the segment 4 is excavated, the segment 4 is By assembling it, it can be shielded sequentially.

In addition, a tail seal lO is provided at the rear end of the shield frame 3 to stop water between the shield frame 3 and the segments 4 that are being dug, and to fill the space between the ground and the segments 4. A backfill injection device (not shown) is provided for this purpose.

[Problem to be solved by the invention] In recent years, the utilization rate of underground areas has increased, and underground horizontal structures such as underground pipes for water and sewage systems, subways, and electric wires have become densely packed, especially in urban areas. It is set up as follows. For this reason, even if there is a demand for additional cables, it is extremely difficult to construct new horizontal tunnels to accommodate this demand. One possibility is to expand the diameter of the pipe (tunnel). In this case, excavating while demolishing the existing buried pipes will interrupt the use of the existing facilities during the construction period, so it is desirable to excavate at the same time as the pipes are put into service.

However, there has never been a shield excavator that can excavate existing tunnels while leaving them in service without affecting them.

In addition, even if the excavator is simply transformed into a hollow and simplified shape and is used to excavate around existing buried pipes, it is possible to prevent groundwater (muddy water) from entering the gap between the machine body and the existing buried pipes. Failure to do so will make it impossible to work inside the shield.

In view of the above circumstances, the present invention was devised to provide a shield tunneling machine that can expand the diameter of an existing tunnel without affecting its use.

[Means for Solving the Problems] The present invention forms a shield frame having a cutter for excavating the outer periphery of an existing buried pipe, and includes a shield frame that shields the existing buried pipe side and the machine body measurement. An inner shell is provided to make the inner tube wall oval.

[Operation] With the above configuration, the shield frame excavates a tunnel around the outer periphery of the existing buried pipe by rotating the cutter. An inner pipe wall is constructed for the inner shell in parallel with this excavation to shield the opening of the machine body and the existing buried pipe to prevent infiltration of groundwater and muddy water.

[Example] Hereinafter, an example of the present invention will be described with reference to the attached drawings.

FIG. 1 and FIG. 2 show an embodiment of a shield tunneling machine according to the present invention, and the same ovals or the same reference numerals as the conventional ones are used, and the explanation thereof will be omitted.

This shield excavator mainly has an oval shape including a shield frame 23 having a cutter 22 for excavating the outer periphery of an existing segment 21, which is an existing buried pipe, and an inner shell 24 provided on the shield frame 23.

The cutter 22 includes a cutter frame 25 formed in a donut shape, and cutter bits 2 appropriately arranged on the front end surface of the cutter frame 25.
6, and the inner diameter of the cutter frame 25 is slightly larger than the outer diameter of the existing segment 21. Further, the cutter bit 26 located closest to the axis is formed so as to be able to cut the backfilling material (mortar) m distributed on the outer wall of the existing segment 21.

The shield frame 23 has an outer shell 27 that is approximately equal to the outer diameter of the cutter 22 and a partition wall 28 that blocks the rear part from the face, and an inner shell 24 that is connected to the cutter frame 25.
It has a diameter substantially equal to the inner diameter of the shell 27 and is concentric with the outer shell 27, and these are arranged vertically and horizontally (not shown) as appropriate. The inner shell 24 is shaped to have the same axial length as the outer shell 27, and is located in the excavation path and is connected to the machine body and the existing segment 21II! It is designed to shield l and
An erector 30 similar to the erector 5 for assembling the newly constructed segment 29 by excavation is provided. That is, by assembling the temporary segments 31 that will become the inner pipe wall, groundwater or drilling mud that infiltrates from the curved face into the gap between the cutter 22 and the inner 1a 24 and the existing segment 21 will enter the excavated tunnel. It is designed to prevent Further, a tail seal 32 for stopping water between the overlapping inner shell 24 and the temporary segment 31 is provided at the t&end of the inner shell 24, similar to the tail seal 10 of the outer shell 27. In addition, an intermediate ring 33 extending rearward toward the shield frame 23 is connected to the forceter 22, and a shaft block 34 is attached to the extending end side. A bearing portion 35 for appropriately bearing the shaft block 34 is formed between the outer shell 27 and the inner shell 24. Furthermore, a rack 36 is formed at the rear end of the shaft block 34, and a drive motor 38 having an output @37 that meshes with the rack 36 is fixedly supported within the shield frame 23. That is, the cutter 22 is rotationally driven by the drive motor 38 via the intermediate ring 33. Further, a digging jack 39 for obtaining a predetermined propulsive force is fixed to the outer shell 27, and when the tip of the advancing/retracting rod 40 comes into contact with the newly installed segment 29, a reaction force is obtained. ．． These digging jacks 39 are arranged at equal intervals in the circumferential direction, as shown in FIG. Furthermore, the shield frame 23 has a mud pipe 4 similar to the conventional one.
1 and a sludge drainage pipe 42 are provided with appropriate extensions. Next, the operation of this embodiment will be explained.

When expanding the diameter of a shield tunnel in use with gables etc., first the shield frame 23 is set concentrically with the existing segment 21 in the starting shaft (not shown). Then, by operating the driving motor 38 and excavation jack 39 while circulating mud water through the mud feeding pipe 41 and the mud draining pipe 42, the outer periphery of the existing segment 21 is excavated using the rotation and propulsive force of the cutter 22.

During this excavation, groundwater and muddy water infiltrates backward through the gap between the cutter 22 and the existing segment 21 (layer of uncut injection material m), but the shield frame 23 is blocked by the inner shell 24. It is shielded. After excavating a predetermined length, shorten the three excavation jacks and use the erecta 5 to excavate the new segment 2 for the excavated length.
Perform step 9 assembling. In parallel with this assembly, the inner shell 2
A temporary segment 31 is assembled by the erector 30 in front of f&l of No. 4. With this, the inside of the new segment 29, which is the side of the machine body, is cut off from groundwater and muddy water passing between the inner shell 24 and the existing segment 2l.

After the assembly of the segments 29.31 is completed, by applying a reaction force to the newly installed segment 29, the excavation by the cutter 22 and the shield frame 23 and the assembly of the segments 29.31 are repeated, and a cross section is formed on the outer periphery of the existing segment 21. Concentric enlarged tunnels are constructed.

In this way, the inner shell 24 is provided on the shield frame 23 that excavates the outer periphery of the existing segment 21, and the inner shell 24 itself and the temporary segment 31 connect the machine body and the existing segment 21.
Since the gap between the tunnel and the tunnel is sealed, the work environment inside the shield can be maintained, and a shield tunnel with an enlarged diameter can be constructed without affecting the existing tunnel.

In other words, excavation work can be carried out in parallel with existing pipe facilities while they remain in use, contributing to shortening the construction period when carrying out scale expansion works such as adding cables.

In addition, when this new tunnel is put into service, the temporary segment 31 will be dismantled and the excavated space will be used more effectively. Therefore, since the function of the temporary segment 31 is mainly to stop water during excavation work, it may have a simpler structure than the new segment 29, which is a permanent structure. Further, the existing segment 21 may be left as is or may be destroyed after excavation is completed, and can be used as a versatile tunnel.

[Effects of the Invention] In summary, according to the present invention, the following excellent effects are achieved.

A shield frame was formed with a cutter that excavated the outer periphery of the existing buried pipe, and an inner shell was provided on this frame to construct an inner pipe wall that shielded the existing buried pipe measurement from the machine body measurement. The diameter of the tunnel can be expanded while keeping the existing equipment in use, and the working environment can be maintained by ensuring that water is cut off between the existing buried pipe and the machine body.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a shield tunneling machine according to the present invention, and FIG.
The figure is a sectional view taken along the line 1 and 2 in Fig. 1, and Fig. 3 is a side sectional view showing a conventional shield tunneling machine.

Claims (1)

[Claims] 1. Form a shield frame with a cutter that excavates the outer periphery of the existing buried pipe, and install an inner wall on the shield frame to construct an inner pipe wall that shields the existing buried pipe side and the machine body side. A shield excavator characterized by having a shell.