JP2835853B2 - Shield excavation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a shield excavation method.

<Conventional technology> There are a case where a subway road tunnel is constructed by an excavation method and a case where a shield excavation method is used.

In recent years, underground urban areas have become overcrowded, and new subway lines have to be built deep underground.

Under such circumstances, it can be said that the construction of the railway station should be performed by the shield excavation method.

As a conventional method of constructing a subway tunnel, as shown in FIG. 11, two main tunnels a are constructed at intervals by a shield machine, and then a slide surface b formed in the main tunnel a is formed. The shield excavation method of excavating the station by sliding the roof shield c has been adopted.

<Problems to be solved by the present invention> The following problems exist in the conventional shield excavation method described above.

That is, in the conventional method, after the main line tunnel a is constructed, the roof shield c must be slid along the main line tunnel a to excavate the station part, so that the tunnel part and the station part can be constructed simultaneously. No, it requires a long construction period.

In addition, extra materials such as segments are required to connect the already constructed main line tunnel a to the station, which is uneconomical.

In order to construct the main line tunnel a and the station at the same time, known methods such as earth pressure type DOT method and muddy water type MF method have been proposed.

However, in these methods, it is possible to construct the main line tunnel a and the station at the same time. However, in order to further extend and construct the main line tunnel a, a separate shield machine must be used.

Therefore, since many shield machines are required, it is uneconomical, and replacement work of the shield machines is troublesome, resulting in a decrease in construction efficiency.

<Object of the present invention> The present invention has been made in order to solve the above-described problems, and it is possible to construct a tunnel section and a station section of a subway at the same time, and using the same shield machine as it is. It is another object of the present invention to provide a shield excavation method capable of further extending only the tunnel portion.

<Configuration of the Present Invention> Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

<A> Structure of shield machine (FIGS. 1 to 5) The shield machine of the present invention includes a main line shield machine 1 and a connection shield machine 2.

(A) Main line shield machine The main line shield machine 1 has a cutter 11 on the front of the excavation,
This is a known shield machine having a circular or elliptical cross section.

As shown in FIGS. 1 and 2, this main line shield machine 1 is
The cutters 11 are located on the same side and are arranged in parallel at a predetermined interval.

A space necessary for constructing a station is secured between the main line shield machines 1.

(B) Connected Shield Machine Next, these main line shield machines 1 are connected by the connected shield machine 2.

This connecting shield machine 2 is formed in a cross-sectional shape that matches the shape of the gap between the main line shield machines 1.

For example, as shown in FIG. 1, it is conceivable that three circular shielded machines having the same diameter are stacked while being shifted from each other, and the overlapping portions on both sides of the intermediate shielded machine are cut away.

And the main line shield machine 1 and the connection shield machine 2 on both sides
The spaces are integrally connected with bolts or the like.

(C) Cutter of connected shield machine A cutter 21 is attached to the front of the excavation of the connected shield machine 2.

The shape of the cutter 21 may be any shape that does not prevent the main line shield machine 1 from separating and excavating after the construction of the station is completed.

The present embodiment is a case where two spoke type cutters 21 are used in the upper and lower sides.
This is a case where it is mounted slightly forward of the cutter 11 of FIG.

Further, the size of the cutter 21 may be such that the upper and lower portions are meshed with each other or not.

In the former case, the rotation is controlled using a gear or the like so as not to collide with each other.

(D) Tail ring As shown in FIGS. 2 and 3, a tail ring 22 having the same shape as the outer shape of the integrated three shield machines is integrally formed at the tail side end of the connected shield machine 2. .

The axial width of the shield of the tail ring 22 is formed to be the segment width + the length required for water stoppage.

As shown in FIG. 5, a ring girder 3 is attached to a connecting portion between the tail portion 12 and the tail ring 22 of the main line shield machine.
Are arranged and connected with bolts 31.

Also, on the inner peripheral surface of the tail ring 22 and the tail portion 12,
Attach the tail seal 32.

 FIG. 4 is a cross-sectional view taken along the line II of FIG.

As can be seen from FIG. 4, the cutter side from the tail ring 22 is connected in the shape of each shield machine and can be separated.

<B> Simultaneous Construction of Main Line Tunnel and Station Unit The main line tunnel 4 and the station unit 5 as shown in FIG. 3 are simultaneously excavated by excavating the shield machine group integrally formed as described above.

And, along with the excavation, the tunnel segment 41 and the station segment continuous in the circumferential direction
Assemble 51.

In this way, parallel tunnels connecting the peripheral surfaces can be constructed.

The constricted portion between the main line tunnel 4 and the station 5 may receive a columnar segment, or may be received by a temporary support to form a post.

<C> Separation and extension construction of main line tunnel Before assembling the final station segment 52 of the station section 5, as shown in FIG. Dig for one ring.

Next, the bolt 31 and the like are removed, and the main line shield machine 1 and the connection shield machine 2 are separated.

Next, as shown in FIG. 7, the final station segment 52 and the tunnel segment 41 are assembled.

Then, as shown in FIG. 8, only the main line shield machine 1 is excavated by the propulsion jack 6 while the connecting shield machine 2 and the tail ring 22 are left.

In addition, the connecting shield machine 2
Do the earth retaining after the removal.

In this manner, as shown in FIG. 9, the main line tunnel 4 separated from the station section 5 can be extended and constructed.

<Other Embodiments> In the above embodiment, the upper and lower spoke-type cutters 21 are attached to the connecting shield machine 2, but as shown in FIG. 10, only one cutter 23 may be attached. .

<Effects of the Present Invention> Since the present invention has been described above, the following effects can be expected.

<A> The conventional method using a roof shield requires a long construction period because the main line tunnel and the station cannot be constructed at the same time.

On the other hand, according to the present invention, the main line shield machine and the connection shield machine can be integrated, and the main line tunnel and the station can be simultaneously constructed.

 Therefore, the construction period can be shortened.

<B> In addition, in the conventional case, extra materials such as overlapping segments are generated to connect the separately constructed main line tunnel and the station, and it takes time to remove and reinforce the main line tunnel segment. Uneconomical.

On the other hand, the present invention is to assemble circumferentially continuous segments on the inner peripheral surface of the tail portion of each shield machine.

Therefore, there is no extra material such as segments at the overlap between the main line tunnel and the station, and there is no need to remove and reinforce the main line tunnel segment. Therefore, it is not necessary to use auxiliary means such as ground improvement even in construction on soft ground.

 Therefore, it is economical and leads to shortening of the construction period.

<D> Since the main line tunnel and the station can be constructed at the same time,
It is easy to manage, and the space in the station can be used effectively for storage of materials and water changes.

<E> Conventional methods such as the conventional earth pressure type DOT method and the muddy type MF method can construct the main line tunnel and the station at the same time, but after that, in order to further extend and construct the main line tunnel Must use a separate shield machine.

Therefore, since many shield machines are required, it is uneconomical, and replacement work of the shield machines is troublesome, resulting in a decrease in construction efficiency.

On the other hand, according to the present invention, after the main tunnel and the station are constructed to a required distance, the main shield machine can be separated from the connecting shield and excavated.

Therefore, the main line tunnel separated from the station can be extended and constructed by the same shield machine, which is economical and can improve the construction efficiency.

<F> The tail ring of the present invention can be manufactured at a factory and can be easily attached to and detached from the shield machine group.

Therefore, it is not necessary to use a firearm at the site, and the work of separating the shield machines can be easily performed.

In addition, since firearms are not required, separation work can be easily performed even in the ground where there is groundwater.

[Brief description of the drawings]

 FIG. 1: Front view of one embodiment of the shield machine of the present invention FIG. 2: Plan view of the shield machine FIG. : Illustration of other embodiments Fig. 11: Illustration of conventional technology

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E21D 9/08 E21D 9/06 301

Claims (2)

(57) [Claims] A main shield machine arranged in parallel at intervals is integrally connected by a connecting shield machine having a shape adapted to the shape of a gap between the main shield machines, and a tail-side end of the connecting shield machine. The tail ring equal to the outer shape of the integrated shield machine group is formed integrally, and while assembling segments on the inner surface of this tail ring, the shield machine group is excavated, and parallel tunnels connecting between the peripheral surfaces are connected. A shield excavation method characterized by construction. 2. A main shield machine, which is arranged in parallel at intervals, is integrally connected by a connecting shield machine having a shape adapted to a shape of a gap between the main shield machines, and a tail end of the connecting shield machine. The tail ring equal to the outer shape of the integrated shield machine group is formed integrally, and while assembling segments on the inner surface of this tail ring, the shield machine group is excavated, and parallel tunnels connecting between the peripheral surfaces are connected. After construction, the main shield machine and the connecting shield machine are separated, and the main shield machine is excavated while assembling segments on the inner peripheral surface of the tail part to construct a tunnel.