JPS6342074B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is directed to an eccentric construction of an existing shield tunnel in an area to be expanded on the outer periphery of an existing shield tunnel in order to form, for example, a subway station premises or a sewer pipe connection part. This invention relates to an expanding shield machine for excavating expanded tunnels.

(Prior Art) Conventionally, as shown in FIGS. 1 and 2, this type of expanding shield machine has an inner cylinder b for guiding and a shielding cylinder eccentric to each other, which are propelled in the axial direction along the outer periphery of an existing shield tunnel a. A double inner and outer cylindrical shield machine body d consisting of an outer cylinder c is provided with a blade opening e on the front side in the direction of propulsion c, and a plurality of propulsion jacks f are provided along the inner periphery of the outer cylinder c. It is common to prepare.

(Problems to be Solved by the Invention) The conventional expanding shield machine has a propulsion jack f... and a blade part e between the inner cylinder b for guiding and the outer cylinder c for shielding of the shield machine main body d. Since it is necessary to provide an installation space for the excavated soil or a discharge space for the excavated soil, it is not possible to bring the inner cylinder b and the outer cylinder c very close together, and therefore the eccentricity between the inner cylinder b and the outer cylinder c It has the disadvantage of being limited in quantity.

(Means for Solving the Problems) The present invention eliminates the disadvantages of the conventional expanding shield machine, increases the amount of eccentricity between the inner cylinder and the outer cylinder of the shield machine body, and therefore reduces the eccentricity with respect to the existing shield tunnel. The purpose is to provide an expansion shield machine capable of excavating a large-volume expansion tunnel. At the front side in the propulsion direction of the shield machine body, which has a dual inner and outer cylindrical shape and is composed of an inner cylinder for guiding and an outer cylinder for shielding, which are eccentric to each other and propelled in the axial direction along the outer periphery of the shield tunnel. In an enlarged shield machine that is equipped with a blade opening and a plurality of propulsion jacks along the inner periphery of the outer cylinder, the area of the inner cylinder of the shield machine body that is closest to the outer cylinder is aligned in the axial direction. It is characterized by an inward convexity along the entire length.

(Embodiment) An embodiment of the expanding shield machine of the present invention will be described below with reference to the accompanying drawings.

In the figure, reference numeral 1 indicates the shield machine main body, which consists of a plurality of shield machine division units 2 each having a substantially fan-shaped cross section, assembled into a donut shape with bolts, etc., and an inner cylinder 3 for guiding and an outer cylinder 4 for shielding that are eccentric to each other. It has a double inner and outer cylindrical shape, and a fixed cutter-type blade part 5 is provided along the inner periphery of the edge on the propulsion direction side of the outer cylinder 4 of the shield machine body 1. A propulsion jack 6 is provided for each of the divided units 2 at the rear. Although this configuration is not particularly different from the conventional one, according to the characteristics of the present invention, the outer tube 4 of the inner tube 3 of the shield machine main body 1 is
The area closest to the shield tunnel 7 is inwardly protruded over its entire length along its axial direction, and the protrusion 7 promotes a space 10 formed by, for example, removing some of the segments 9 of the existing shield tunnel 8. I did it like that. In the illustrated example, two parts of the shield machine dividing unit 2 in the area where the inner cylinder 3 and the outer cylinder 4 of the shield machine main body 1 are closest are convex inward so that the inner cylinder side is separated from the outer cylinder side. I decided to let them in.
Therefore, even if the eccentricity between the inner cylinder 3 and the outer cylinder 4 of the shield machine main body 1 is increased, there will be a gap between the inner cylinder 3 and the outer cylinder 4 in the area where the inner cylinder 3 and the outer cylinder 4 are closest to each other. A relatively large space can be provided, the propulsion jack 6 can be installed there, and a sufficient space can be provided for discharging excavated soil. Furthermore, the expanding shield machine of the present invention can be easily assembled by simply replacing only a portion of the shield machine dividing unit constituting the shield machine main body of the conventional expanding shield machine.

Instead of the fixed cutter described above, the blade mouth portion 5 may be configured to include a rotary cutter, a muddy water excavation device, or the like between the inner cylinder 3 and the outer cylinder 4 of the shield machine main body 1.

Next, a method for excavating an enlarged tunnel using the enlarged shield machine of the present invention will be explained.

First, although not shown, one end of the planned expansion area 11 of the existing shield tunnel 8 is expanded by, for example, excavating a vertical shaft or using the expansion shield excavation method (Japanese Patent Application Laid-Open No. 59-21892) proposed earlier by the present applicant. A starting base for the shield machine is formed, and the expanding shield machine of the present invention is assembled and installed there.

Next, among the segments 9 forming the existing shield tunnel 8, one segment 9 corresponding to the convex part 7 of the inner cylinder 3 of the expanding shield machine is removed, and the space 10 to be formed after removal is filled with the segment 9 of the expanding shield machine. The convex part 7 of the inner cylinder 3 is inserted, and the expansion shield machine is propelled by the propulsion jack 6 while taking the reaction force by a suitable reaction force receiver (not shown) to excavate the outer periphery of the existing shield tunnel 8. . The excavated soil is placed in the inner cylinder 3 and outer cylinder 4 of the expanding shield machine.
It is discharged to the rear of the expansion shield machine through the space formed between the expansion shield machine and the expansion shield machine. Next, the remaining segments 9 in the inner cylinder 3 of the expansion shield machine are disassembled, one segment 9 in front of the convex part 7 of the inner cylinder 3 is removed, and a segment for the expansion tunnel is installed at the rear of the expansion shield machine. are assembled, and the expanding shield machine is further propelled by the propulsion jack 6 using the segments as reaction force receivers to excavate the outer periphery of the existing shield tunnel 8. Such excavation work is repeated to form an enlarged tunnel eccentrically around the outer periphery of the existing shield tunnel 8.

As shown in Figure 6, the segment 9 for removal of the existing shield tunnel 8 is composed only of an outer wall 12 and a reinforcing frame 13 inside the outer wall 12, and has a relatively simpler structure than a normal segment. Furthermore, a reinforcing member 15 is interposed between the segments 9 at both ends of the space 10 formed after the segments 9 are removed by using brackets 14 provided in advance on each segment 9 at both ends. 15
The space between the shield tunnel 8 and the removal segment 9 is filled with a filler 17 such as mortar through a filler injection pipe 16 penetrating the reinforcing member 15 to reinforce the existing shield tunnel 8.

(Effects of the Invention) According to the present invention, the region of the inner cylinder of the shield machine main body that is closest to the outer cylinder is convex inward over the entire length along the axial direction, so that the inner cylinder of the shield machine main body A relatively large space can be provided between the inner cylinder and the outer cylinder even in the area where the outer cylinder is closest to the outer cylinder. It has the effect of being able to excavate.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional expanding shield machine propelling the outer periphery of an existing shield tunnel, Figure 2 is a sectional view taken along the line -, and Figure 3 is the expanding shield machine of the present invention propelling the outer periphery of an existing shield tunnel. A front view of one embodiment of the invention, FIG. 4 is a sectional view taken along the line
FIG. 5 is a perspective view of the existing shield tunnel, and FIG. 6 is a perspective view of a segment for removal of the existing shield tunnel. 1... Shield machine body, 3... Inner cylinder, 4... Outer cylinder, 5... Blade opening, 6... Propulsion jack, 8...
Existing shield tunnel, 9...Segment, 10
...Space section, 11... Area scheduled for expansion.

Claims (1)

[Claims] 1. An expansion shield machine for excavating an expansion tunnel eccentric to the shield tunnel in a planned expansion area on the outer periphery of an existing shield tunnel, which is a mutually eccentric guide machine that is propelled in the axial direction along the outer periphery of the shield tunnel. The main body of the shielding machine has a dual inner and outer cylindrical shape, which is composed of an inner cylinder and an outer cylinder for shielding, and has a blade opening on the front side in the direction of propulsion, as well as a plurality of propulsion jacks along the inner periphery of the outer cylinder. An expanding shield machine characterized in that a region of the inner cylinder of the shield machine main body that is closest to the outer cylinder is convex inward along its entire length along its axial direction.