JP2002364286A - Reaction receiving structure of tunnel branch part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reaction receiving structure of a tunnel branch part, which allows smooth boring to be performed by respective shield machines for boring unit tunnels branching off from a large section tunnel. SOLUTION: Reaction receiving bodies 11 for obtaining propulsive reactions of the shield machines 1 and 2 for boring the unit tunnels B and C, respectively, are provided, in the branch part (1) wherein the unit tunnels B and C branch off from the large section tunnel A so as to be bored. The body 11 is composed, in a framework-like manner, of upper and lower horizontal materials 12 and 13 which are installed along an axial direction of the tunnel A inside steel shell concrete installed in a ceiling part (2) of the tunnel A and a roadbed part (3) thereof, respectively, a plurality of supports 14 which are erected to the side of the unit tunnels B and C between the materials 12 and 13, and a plurality of diagonal members 15 which are installed between the support 14 and the material 12 and between the support 14 and the material 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reaction force receiving structure at a branch portion between a large-section tunnel and a single tunnel. For example, a subway station building and a main line tunnel through which a train passes are connected to one large space by a shield method. This method is applied to the case where a tunnel is constructed and then a plurality of main tunnels are constructed by a shield method.

[0002]

2. Description of the Related Art In recent years, underground roads such as roads and sidewalks in urban areas, or tunnels used as subways are used as double-track tunnels, or one large space that connects a subway station building and a main line tunnel through which a train passes. In the case of continuous construction, it may not be possible to perform construction separately due to restrictions on the structure, construction, or land use.

As a method of constructing an underground structure in such a case, for example, as shown in FIGS. 5A and 5B, one of two or more circles or a combination of a circle and a square is used. A construction method of a large-section tunnel in which a plurality of single tunnels are excavated as one continuous large-section tunnel A by one shield machine 20 has been developed.

After excavating a certain section as a large section tunnel, a plurality of shield machines 20a, 20b, 20c combined into one unit are separated into independent shield machines, and each shield machine 20a, 20b, 20c has further developed a method of constructing a tunnel for excavating a plurality of independent single tunnels B and C.

At this time, each shield machine 20a, 20
4b and 20c, as shown in FIG. 4 (c), excavating the unit tunnels B and C respectively with the segment 21 incorporated in the ground of each unit tunnel at the tail part as a reaction force receiving of the propulsion jack 22. Becomes

[0006]

However, at the junction between the large-section tunnel A and each of the individual tunnels B and C, the segment 21 is normally incorporated on the ground side as shown in FIG. 4D. Therefore, although this segment 21 can be used as a reaction force receiver for each of the shield machines 20a, 20b, and 20c, a segment that can be a reaction force receiver for the shield machines 20a, 20b, and 20c is provided at the boundary E between the single tunnels B and C. Since it is not particularly incorporated, it is necessary to provide a separate structure for receiving a reaction force, and development of such a structure has been desired.

The present invention has been made in view of such circumstances. In particular, at a branch portion between a large-section tunnel and each of the individual tunnels branching from the large-section tunnel, the single-section tunnel is branched from the large-section tunnel. An object of the present invention is to provide a reaction force receiving structure of a tunnel branching section that enables each shield machine to be dug smoothly excavated.

[0008]

According to a first aspect of the present invention, there is provided a reaction force receiving structure for a tunnel branch portion, wherein the single tunnel is provided at a branch portion between a large-section tunnel and a single tunnel that is excavated from the large-section tunnel. And a reaction force receiving body for obtaining a propulsion reaction force of the shield machine for excavating the vehicle.

According to a second aspect of the present invention, there is provided a reaction force receiving structure for a tunnel branch portion, wherein the reaction force receiving body is provided in a shaft-like shape or a wall shape. It is characterized by.

According to a third aspect of the present invention, there is provided a reaction force receiving structure for a tunnel branch portion, wherein the reaction force receiving member comprises an S structure, an RC structure or an SRC structure. It is characterized by having been done.

[0011]

1 (a) to 1 (c) show a large section tunnel A constructed in a laterally long rectangular section and a branch from the large section tunnel A, each of which is excavated independently. The figure shows a central unit tunnel B having a rectangular cross section and a branching portion with a unit tunnel C having a circular cross section on both sides of the single tunnel B.

The large-section tunnel A is provided with face plates 1a, 2a arranged at the center and at both sides thereof as shown in FIG.
a is a shield machine 1 having a rectangular plate shape
And one shield machine 3 composed of a combination of two shield machines 2 and 2 having a circular plate shape.

The single tunnel B at the center and the single tunnel C on both sides of the large tunnel T are separated from the single shield machine 3 by the single shield machines 1 and 2, respectively. Each is excavated.

Further, the ground of the large-section tunnel A excavated in this way, the ground of each of the unit tunnels B and C, and the ground of the branching point A between the large-section tunnel A and each of the unit tunnels B and C are steel shells. Steel lining concrete or steel segments formed by casting concrete inside, or lining with a lining material 4 such as a steel segment or an RC segment. Is, for example, FIG.
As shown in (c), the steel 6 is covered with a steel shell concrete segment formed by placing concrete 6 in a steel shell 5.

In this case, the steel shell 5 includes, for example, a plurality of main girders 7 arranged parallel to the circumferential direction of the large-section tunnel A and at predetermined intervals in the axial direction of the large-section tunnel A, and the main girders 7. , 7 are formed from a plurality of vertical ribs 8 installed along the axial direction of the large-section tunnel A, the main girder 7, and a skin plate 9 installed on the ground side of the vertical ribs 8.

The main girder 7 is a main structural member of the steel shell 5, which mainly resists earth pressure from the ground side as a beam (bending material), and has a beam structure and a thickness corresponding to the beam. For example, it is formed from a shaped steel such as a strip steel, an I-shaped steel, or an H-shaped steel.

The vertical rib 8 mainly serves as a reaction force receiving when the shield machines 1 and 2 excavate a tunnel, and has a cross section corresponding to that of the main girder 7 such as a steel material, for example, a belt. It is formed from steel, I-beam, or H-beam.

The vertical ribs 8 are provided on the shield machines 1 and 2.
Are installed along the axial direction of the large-section tunnel A between the main girders 7, 7 on the ground side, where the propulsion jack (not shown) is disposed.

At this time, since a plurality of propulsion jacks of the shield machines 1 and 2 are generally arranged at predetermined intervals in the circumferential direction of the large-section tunnel A, the vertical ribs 8 are also adjusted accordingly. A plurality is provided at predetermined intervals in the circumferential direction.

The skin plate 9 is a surface member that directly receives the earth pressure from the ground, is formed of a thin steel plate, and has a main girder 7.
And it is installed on the ground side of the vertical rib 8.

The steel shell 5 thus formed is installed adjacent to the large section tunnel A in the circumferential direction and the axial direction on the ceiling portion B and the roadbed section C of the large section tunnel A, and particularly in the large section tunnel A. In the joint portion between the steel shells 5 and 5 which are adjacent to each other in the circumferential direction of A, the ends of the two main girders 7 abut against each other and are integrally joined by bolting or welding.

In addition, as shown in FIG. 1B, for example, a branch segment for closing a gap between the end surfaces of the large-section tunnel A is provided at a branch portion between the large-section tunnel A and the single tunnels B and C. 10 is attached.

Further, at the junction between the large-section tunnel A and the single tunnels B and C, the shield machines 1 and 2 that independently excavate the single tunnels B and C branched from the large-section tunnel A, respectively. The reaction force receiving body 11 is installed in a configuration as shown in FIGS. 3 and 4, for example.

The reaction force receiving member 11 excavates the single tunnels B and C when excavating the pit portions of the single tunnels B and C respectively branched from the large section tunnel A from the side of the large section tunnel A to a certain depth. A single tunnel T at the center, which serves as a reaction force to advance the shield machine.
And at both sides of the boundary between the unit tunnel C and the unit tunnel C.

The reaction force receiving member 11 is removed in principle after excavating the pit portions of the single tunnels B and C from the side of the large-section tunnel A to a certain depth, but is removed in principle. It may be installed.

The reaction force receiving body 11 in this case will be described with reference to, for example, the examples of FIGS. 3A and 3B. An upper horizontal member 12 and a lower horizontal member 13 installed along the axial direction of the tunnel A, and a plurality of pillars erected near the unit tunnels B and C between the upper and lower horizontal members 12 and 13. 14 and this support 14 and upper and lower horizontal members 1
A plurality of diagonal members 15 installed between the members 2 and 13 form a shaft.

The upper and lower horizontal members 12 and 13, the support 14 and the diagonal member 15 are all formed from a shaped steel such as an H-section steel, and the upper and lower horizontal members 12 and 13 are fixed to the main girder 7 of the steel shell 5 by fixing bolts. Alternatively, each is fixed by welding or the like.

The column 14 is composed of upper and lower horizontal members 12 and 13.
In addition, the diagonal member 15 is composed of the column 14 and the upper and lower horizontal members 12 and 13.
Are connected to each other by connecting bolts or welding.

In this case, a plurality of the upper and lower horizontal members 12 and 13 are attached at predetermined intervals in the circumferential direction of the tunnel A, and a column 14 is provided between the upper and lower horizontal members 12 and 13, respectively. Upper and lower horizontal members 12 and 13
The diagonal members 15 are provided between them.

In the example shown in FIGS. 4A and 4B, the reaction force receiving member 11 is provided at the end of the large section tunnel A on the side of the single tunnel B or C in the axial direction of the tunnel A by the RC structure or the SRC structure. It is constructed as a continuous wall. Note that S
In the case of the reaction force receiver having the RC structure, the reaction force receiver 11 shown in FIG. 3 may be constructed as a steel frame.

In such a configuration, the shield machines 1 and 2 separated from each other set the propulsion jacks 1b and 2b on the reaction force receiving body 11 and the lining material (segment) 4 on the ground side, respectively, and set the single tunnels B and C can be dug respectively.

[0032]

The present invention has been described above.
At the junction between the large-section tunnel and each single tunnel that branches off from the large-section tunnel, a reaction force receiver is provided to obtain the propulsion reaction force of each shield machine separated from each other. Each shield machine that excavates a plurality of single tunnels can be advanced smoothly.

[Brief description of the drawings]

FIG. 1A is a partial perspective view of a large-section tunnel, and FIG.
FIG. 2 is a perspective view showing a branch portion between a large-section tunnel and a single tunnel, and FIG. 2C is a partial perspective view of a lining material made of a steel shell and concrete.

FIG. 2 is a perspective view of the shield machine.

FIG. 3 shows a reaction force receiving body, (a) is a cross-sectional view showing a branch portion between a large-section tunnel and a single tunnel, and (b) is (a).
3 is a sectional view taken along the line II in FIG.

FIGS. 4A and 4B show a reaction force receiving body, wherein FIG.
3 is a sectional view taken along the line II in FIG.

5 (a) and 5 (b) are perspective views of a shield machine,
(C) is a partial cross-sectional view of the shield machine tail, (d)
FIG. 4 is a sectional view of a tunnel branching portion.

[Explanation of symbols]

 A Large section tunnel B Single tunnel C Single tunnel 1 Shield machine 2 Shield machine 3 Shield machine 4 Lining material 5 Steel shell 6 Concrete 7 Main girder 8 Vertical rib 9 Skin plate 10 Branch segment 11 Reaction force receiver 12 Upper horizontal member 13 Lower horizontal material 14 Prop 15 Diagonal material

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yutaka Sudo 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. F-term (reference) 2D054 AA03 AB01 AB03 AB05 AC02 AD32 EA05 EA09

Claims (3)

[Claims] 1. A reaction force receiving member for obtaining a propulsion reaction force of a shield machine that excavates the single tunnel is provided at a branch portion between the large tunnel and a single tunnel that branches and excavates from the large tunnel. A reaction force receiving structure for a tunnel branch portion, which is characterized in that: 2. The reaction force receiving structure according to claim 1, wherein the reaction force receiving body is provided in a frame or wall shape. 3. The reaction force receiving body is of S structure, RC structure or S structure.
3. The reaction force receiving structure for a tunnel branch according to claim 1, wherein the reaction force receiving structure is constituted by an RC structure.