JPH0454795B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a method for constructing a double-track tunnel in which circular cross sections are partially overlapped.

<<Prior Art>> As is well known, there is a shield construction method as a method for constructing subway tunnels, and in this construction method, a shield excavator is used to excavate the tunnel.

There are various types of shield tunneling machines, but those with a circular cross section are generally widely used.

By the way, subway tunnels usually require two rails, one for the upper and one for the upper and lower lines.

In this case, excavating each tunnel individually would be wasteful in terms of land, construction time, and construction costs.

Therefore, it may be possible to excavate a large circular section at once, but although this method is slightly more advantageous in terms of construction time than excavating each section individually, the efficiency of the section deteriorates.

For this reason, for example, as seen in Japanese Patent Application Laid-Open No. 47-44931, a shield excavator has been proposed that excavates with a cross section in which two circular cross sections overlap. Although a good double-track tunnel can be constructed, this method has the following problems.

≪Problems to be Solved by the Invention≫ In other words, in the shield tunneling machine disclosed in the above-mentioned publication, the cross-section is made by overlapping the circular cross-sections, so although the cross-sectional efficiency is improved, the two cutter heads with circular cross-sections are The cutter heads are arranged in a staggered manner, and each cutter head is provided with a drive motor, making the structure complicated.

Moreover, such a cross-sectional shape has the disadvantage that it becomes difficult to control excavation when the shield tunneling machine is rolled, and the shape of the segment becomes complicated.

This invention was made in view of these conventional problems, and its purpose is to provide a double track that can easily control excavation without complicating the structure or segment shape of the shield tunneling machine. The purpose of this invention is to provide a method for constructing a tunnel.

<<Means for Solving the Problems>> In order to achieve the above object, the present invention provides a method for constructing a tunnel in which segments are sequentially assembled and constructed in an excavated hole with a circular cross section excavated by a shield tunneling machine. Using a leading segment in which a notch in an arbitrary shape such as an arc is formed along the axial direction of the tunnel in a part of the outer periphery, the leading tunnel is constructed by filling this notch with excavable filler, and the notch is Using a trailing segment having a shape corresponding to the section, excavate and remove the filling material to expose the notch, and construct a trailing tunnel while partially fitting the trailing segment into the notch. It is characterized by

<<Operation>> According to the method for constructing a double-track tunnel with the above configuration, a double-track tunnel is constructed by fitting and joining the leading and trailing segments of the circular cross section through the notches, so that the leading and trailing tunnels each have a It has a circular cross section, so the shield excavator itself does not become complicated, and its excavation control is not difficult.

Furthermore, since the segments can be designed based on circular cross sections, there are no problems in manufacturing and construction.

<<Example>> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show an embodiment of the method for constructing a double-track tunnel according to the present invention.

First, the shield tunneling machine 10 used in this embodiment will be explained. The shield tunneling machine 10 shown in FIG. The cutter head 14 is provided with a plate 12 and a cutter head 14 rotatably disposed on the distal end side of the skin plate 12 for cutting a circular cross section.

In the skin plate 12, there is provided a skin plate 12 for propelling the shield tunneling machine 10.
A plurality of shield jacks 18 are provided to take a reaction force to the leading segments 16 that are assembled and installed in sequence on the rear end side.

A partition wall 20 fixed to the skin plate 12 is provided on the back side of the cutter head 14, defining an earth pressure chamber 22 filled with excavated earth and sand to counteract the earth pressure of the face.

This earth pressure chamber 22 is provided with a screw conveyor 24 that penetrates the partition wall 20 and discharges excavated earth and sand in the earth pressure chamber 22 to the outside.

Further, below the shield jack 18,
A press jack 26 is installed, and an arc-shaped press plate 28 is attached to the press jack 26.

The preceding segment 16 used for constructing the preceding tunnel T1 is, as shown in FIG. 1b,
A plurality of divided blocks are assembled into an annular shape, and an arc-shaped notch 30 is formed along the axial direction at the lower part of the outer periphery.

When the leading segment 16 is sequentially installed on the rear side of the skin plate 12 of the shield excavator 10 as the tunnel excavates, the notch 30 is extended along the axial direction of the leading tunnel T1. A filler material 32 such as excavable sand or clay is filled.

The method of filling the filler 32 is as follows:
is inserted before being assembled, and after assembling the preceding segment 16, the press jack 26 is driven and the filler material 32 is compressed by the press plate 28,
To compensate for the volume reduction due to compression, the filler 32 is replenished from the supply pipe 34 attached to the press plate 28, and after the filler 32 is compressed sufficiently to the extent that the accumulation does not decrease even when compressed by the press jack 26, the shield jack 18 and the press jack 26 are linked to propel the shield excavator 10.

When the preceding tunnel T1 is constructed to some extent as described above, the first trailing tunnel T2 is constructed below and parallel to the preceding tunnel T1.

In the construction of the first trailing tunnel T2, Fig. 1a
A shield tunnel excavator having almost the same configuration as the shield tunneling machine 10 shown in FIG. A press jack 26 for compressing the skin plate 12 is installed at a position rotated approximately 90 degrees from the bottom of the skin plate 12.

The trailing segment 36 used to construct the first trailing tunnel T2 has a curvature corresponding to the notch 26 of the leading segment 16, and an arc-shaped notch 30a is formed on the side of the trailing segment 36 in the axial direction. It is formed.

The trailing segment 36 was installed by excavating and removing the filling material 32 filled in the notch 30 of the leading segment 16 with the shield excavator 10 excavating the first trailing tunnel T2, thereby exposing the notch 30. This is performed while the outer periphery of the trailing segment 36 is partially fitted into the notch 30 in this state.

In this case, the notch 30a of the trailing segment 36
A filler material 32 is also filled inside and compressed using a press jack.

When the first trailing tunnel T2 is constructed to a certain extent, a second trailing tunnel T3 is formed on the side thereof.
construction will be carried out in parallel.

In this embodiment, the second trailing tunnel T3 is
Because it has a completely circular cross-section, shield tunneling machines are used without press jacks.

Further, the segment 36' has a curvature corresponding to the notch 30a of the trailing segment 36, and its installation method is the same as that of the trailing segment 36.

According to the method for constructing a double-track tunnel with the above configuration, at the tip of the circular cross section, the trailing segments 16, 36,
36' are fitted and connected through the notches 30 and 30a to construct a double-track tunnel, so the leading and trailing tunnels T1, T2, and T3 each have a circular cross section, and the structure of the shield excavator 10 itself is not complicated. Moreover, the excavation control can be easily performed.

Further, since the segments 16, 36, 36' can also be designed based on circular cross sections, there are no problems in manufacturing and workability.

FIG. 3 shows another embodiment of the invention,
In this embodiment, a case is illustrated in which a large number of trailing tunnels T2, T3, . . . are constructed in a row on the side of the leading tunnel T1.

In such double-track tunnels, the tunnel is constructed by filling the arc-shaped notch of the leading segment with filler, and when constructing the trailing tunnel, this filler is excavated and removed to fill the notch. It can be easily constructed by exposing the notch and installing the segment on the trailing side while partially fitting into this notch, and the same effect as the above embodiment can be obtained.

In the above embodiment, the notches 30, 30a have an arcuate cross section, but the cutouts 30, 30a may have other shapes such as a half-moon shape.

≪Effects of the Invention≫ As explained in detail in the embodiments above, according to the method for constructing a double-track tunnel according to the present invention, the shield tunneling machine is constructed by adding press jacks and filler to the conventionally widely used circular cross-section shield tunneling machine. Since only the supply equipment is added, the structure is not complicated and the manufacturing cost is low.

Also, since it is basically the same as a circular shield, excavation control can be easily performed.

Furthermore, the segments are almost the same as conventional circular cross sections, so there are no problems with design, fabrication, and construction.

[Brief explanation of the drawing]

FIG. 1a is a vertical cross-sectional view showing an example of a shield tunneling machine used to carry out the method of the present invention, FIG. 1b is a cross-sectional view taken along line A-A in FIG. FIG. 3 is a cross-sectional view showing another example of a tunnel constructed by the method of the present invention. 10... Shield excavator, 16... Leading segment, 30, 30a... Notch, 32... Filling material, 36, 36'... Trailing segment, T1...
Leading tunnel, T2... trailing tunnel.

Claims (1)

[Claims] 1. In a tunnel construction method in which segments are sequentially assembled and constructed in an excavated hole with a circular cross section excavated by a shield tunneling machine, a notch in an arbitrary shape such as an arc is formed in a part of the outer periphery of the segment along the axial direction of the tunnel. Using the formed leading segment, a leading tunnel is constructed while filling the notch with excavable filler, and a trailing segment having a shape corresponding to the notch is used to excavate and remove the filler. A method for constructing a double-track tunnel, characterized in that a trailing tunnel is constructed while exposing the notch and partially fitting the trailing segment into the notch.