JP2835389B2 - Branch shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a branch shield method for constructing a tunnel that branches on the way by a shield method.

[0002]

2. Description of the Related Art Conventionally, in order to construct a tunnel that is branched on the way by a shield method, a branch shaft having a branch shaft at a branch point shown in FIG. 8 and a branch shaft shown in FIG. A line late system, a multi-circle separation system (generally referred to as an H-and-V shield) shown in FIGS. 10 and 11, and a separation system shown in FIGS. 12 and 13 are adopted.

First, in the above-mentioned fork shaft method, a shaft BT3 is provided in advance at a branch site, and a branch shield tunneling machine 2a excavates a branch line tunnel T2 from the shaft BT3 separately from the main line tunnel T1, and then finally starts. The main line tunnel T1 and the branch line tunnel T2 reaching the reaching shaft BT2 from the shaft BT1 are connected by the shaft BT3.

[0004] In addition, in the later-stage branch line system, a main tunnel T1 is provided by a shield excavator (not shown) from a starting shaft BT1.
And the main line tunnel T1 completes excavation up to the destination (for example, the reaching shaft BT2). Then, when the excavation of the main line tunnel T1 is completed, the slipping-out device (track or the like of a slipping-out conveyor / slippering trolley) and the material transporting device, which are referred to as a rear device, are removed, and the branch shield excavator 2a is moved to the starting shaft. It is carried into the completed main line tunnel T1 from the BT1 or the reaching shaft BT2, and excavates the branch line tunnel T2 from the branch point position.

In the multi-circle separation method, a plurality of independent shield machines 1a and 1b are connected biaxially by a connecting body 1c, and when two shield machines 1a and 1b are dug to a branch point, both shield machines 1a and 1b are separated.
b is disconnected and excavation is performed by the respective shield machines 1a and 1b. That is, the branch point P in FIG.
Until the two shield machines 1a and 1b are connected, excavation is performed, and at the branch point P, the connection is released.
At a, the main line tunnel T1 and the other shield machine 1b change the excavation direction to excavate the branch line tunnel T2. In addition,
The shield machines 1a and 1b are usually of the folding type, and their rear bodies are integrally connected by a connector 1c or the like.

Further, the separation system has a double structure in which independent shield machines 1a and 1b are housed in a single outer skin plate 11a, respectively, and has a double structure up to a branch point P in FIG. When excavating with the shield machines 1a and 1b and excavating to the branch point P, both the shield machines 1a and 1b start from the inside of the outer skin plate 11a while leaving the outer skin plate 11a at that location, and each of the shield machines 1a and 1b starts with the main line tunnel T1 and the branch line. The tunnel T2 is dug.

[0007]

However, the above-mentioned conventional method requires the provision of a branch shaft BT3 at the branch point in the branch point shaft system shown in FIG. There are issues that can be achieved. Also,
This method has a problem that it is necessary to construct a vertical shaft BT3 for branching, and the cost is increased accordingly.

In addition, the late branch line system shown in FIG. 9 has a problem that the construction period is inevitably lengthened because the branch line tunnel T2 is dug after the main line tunnel T1 is completed. It has been requested that the branch line tunnel T2 can be excavated in parallel during the excavation of T1. However, during excavation of the main line tunnel T1, rear devices such as a slip-out device and a bogie track are provided behind the main line shield machine. Due to the attachment, it is not possible to carry in the large-diameter branch shield excavator 2a during the excavation of the main line tunnel T1, and these auxiliary devices are removed to remove the branch shield excavator 2a.
Parallel excavation cannot be realized due to the need to carry

On the other hand, in the multi-circle separation method and the separation method shown in FIGS. 10 to 13, the main line tunnel T 1 and the branch line tunnel T 2 can excavate in parallel after the branch point P. The method has a problem that the main line tunnel T2 cannot be largely reduced in diameter after the branch point P.

Accordingly, the present invention has been made in view of the above problems, and provides a branch shield method in which a vertical shaft BT3 for branching is unnecessary, and a parallel tunnel tunnel T2 can be dug without changing the diameter of the main line tunnel T1 on the way. It is intended to do so.

[0011]

In order to solve the above-mentioned problems, the main skin plate 100 of the main line shield excavator 1 is provided with a main skin plate 100 having the above-mentioned features. The body 110, the middle body 120, and the rear body 130 are connected to each other in a folding manner, and a detachable auxiliary skin plate 121 is housed in the intermediate body 120 in a double cylindrical shape. The main line shield that houses the branch line shield excavator 2 is provided on the peripheral surface of the sub skin plate 121, and a window hole 123 through which the branch line shield excavator 2 can start is provided. The propulsion force is obtained by the excavator 1 by the operation of the first shield jack 51 housed in the rear trunk 130, and the front trunk 11
0, the main trunk 120 and the rear trunk 130 are connected to each other, and the main tunnel T1 is dug to the planned branch point, and the connection between the central trunk 120 and the rear trunk 130 is released at the planned branch point. 130 at that branch point,
The auxiliary skin plate 121 is used as a reaction force receiving member, and the propulsion force is obtained by the operation of the second bending jack 52 between the front body 110 and the middle body 120, so that the excavation of the main line shield machine 1 is performed with the front body 110. When the front trunk 110 and the middle trunk 120 are propelled and the rear end of the middle trunk 120 passes through the window 123 of the sub-skin plate 121, it remains at the branch point. The technical means is characterized in that the branch line shield excavator 2 excavates the branch line tunnel T2 from the window hole 123 of the sub skin plate 121 thus formed.

[0012]

Therefore, according to the present invention, since the branch line shield machine 2 is housed in the main line shield machine 1, the branch line shield machine 2 is already installed in the portion dug by the main line shield machine 1. It has been carried in and exhibits an effect that the excavation of the branch line tunnel T2 can be started from a desired branch point during excavation.

The main skin plate 110 functions as a lid for closing the window 123 of the sub skin plate 121 inserted into the inner body 120 thereof.
When the front trunk 110 and the middle trunk 120 are moved forward while leaving the front trunk 21 and the rear trunk 130 at the branch point, an opening 123 for starting the branch line shield machine 2 is opened. The branch line shield excavator 2 is transmitted and the branch line tunnel T2 can be dug in parallel with the main line tunnel T1.

[0014]

Next, an embodiment of the present invention will be described with reference to the accompanying drawings. In the figure, reference numeral 1 denotes a main line shield excavator, and a main skin plate 100 of the main line shield excavator 1 is constructed by connecting a front trunk 110, a middle trunk 120, and a rear trunk 130 in a folding manner. A sub-skin plate 121 which can be inserted and removed is housed in a double cylindrical shape, and a branch line shield excavator 2 is housed in the sub-skin plate 121. A window hole 122 from which the shield machine 2 can start is provided.

The basic structure of the main line shield machine 1 can be a conventionally known one. A bulkhead B partitioned by a partition wall 111 is provided at a front portion of the front body 110, and a bulkhead B is provided at a front end of the bulkhead B. A cutter disk 112 rotated by a drive source (not shown) is attached. In addition,
In the illustrated example, it is assumed that the main skin plate is cylindrical and the cutter disk 112 is disk-shaped, in other words, the tunnel cross section is circular. However, for the tunnel having a rectangular cross section including the branch line shield excavator 2 described below. The main skin plate 100 having a rectangular tube shape and the cutter 112 for rectangular cross section may be used.

The shears excavated by the cutter disk 112 are taken out of the bulkhead B by a suitable shearing device (not shown) and carried out to the ground through the existing main line tunnel T1. It is the same as in the prior art that an appropriate earth pressure or muddy water pressure is applied in the head B.

Further, the main skin plate 100 is
A conventionally known structure may be used to connect the inner body 10, the middle body 120, and the rear body 130 in a folding manner.
And the middle trunk 120 or the middle trunk 120 and the rear trunk 130 may be connected by a plurality of middle-strength jacks, respectively. Is not directly connected to the middle body 120, and the second center bending jack 52 is detachably connected at one end (the base end side) to the other end (rod end side) of the second shield jack 54 as shown in FIG. The other end (rod end side) is attached so as to press the sub skin plate 121. That is, the other end of the second middle bending jack 52 is attached so as to press the one end side flange 122 of the sub skin plate 121.

As shown in FIG. 7, a connecting portion between the middle body 120 and the rear body 130 is connected to the extension body 1 at the rear end of the middle body 120.
24 is detachably extended, and the first middle folding jack 5 is connected to connecting flanges 125 and 129 between the middle body 120 and the extension body 124.
3 is connected to one end (proximal side) of the first middle folding jack 5.
The other end of the rear body 13 is not shown, but is the same as the conventional case.
Connected to 0. In addition, this middle trunk 120 and the extension trunk 12
The rear flange 127 of the auxiliary skin plate 121 is joined to the connecting flanges 125 and 129 with the fourth flange 4 (in this embodiment,
The flanges 129 and 127 are detachably fixed to each other with fixing screws (not shown), but may be simply joined. ).

An unillustrated erector is accommodated in the rear body 130, and the rear body 130 is
It is the same as the prior art that the segments S are sequentially assembled.

The present invention provides a main body shield excavator 1 in which the branch line shield excavator 2 is housed.
The propulsion force is obtained by the operation of the first shield jack 51 accommodated in the front body 110, and the front body 110, the middle body 120 and the rear body 130 are obtained.
Main road tunnel T1 to the scheduled branch point with the
Digging.

That is, the first shield jack 51
Is to propel the main line shield excavator 1 by using the assembled segment S as a reaction force, and this driving force is transmitted from the first shield jack 51 to the rear trunk 130 to which the first shield jack 51 is connected. It is transmitted to the middle body 120 and the auxiliary skin plate 121 via the one-way folding jack 53, and is transmitted from the auxiliary skin plate 121 to the front body 110 via the second intermediate bending jack 52 and the second shield jack 54. The auxiliary skin plate 121 and the middle body 120 are connected to the connecting flange 125,
129 and the rear end flange 127 of the auxiliary skin plate 121
It is designed to be integrally propelled at the junction with the Therefore, as shown in FIG. 2, up to the scheduled branch point,
The front body 110, the middle body 120, and the rear body 130 are connected, and the auxiliary skin plate 121 is inserted into the middle body 120 and kept stored.

Next, when the main line tunnel T1 is dug to the branch point, the middle trunk 120 and the rear trunk 130 are sunk at the branch point.
The connection between the auxiliary skin plate 121 and the rear body 130 is released.
And at the branch point, the secondary skin plate 12
1 is used as a reaction force receiving member, and a propulsion force is obtained by the operation of the second center bending jack 52 between the front body 110 and the middle body 120,
The excavation of the main line shield excavator 1 is performed by the front body 110 and the middle body 120.
Is continued in a state where.

In order to release the connection between the middle body 120 and the rear body 130, only the connection of the connection flanges 125 and 126 shown in FIG. 7 is detached, that is, the connection screw 128 is removed and the connection flange of the extension body 124 is removed. The joined state between 126 and 127 is maintained. Therefore, when the connecting screw 128 is removed from the state shown in FIG. 7 and the middle body 120 is propelled (moves to the left side in FIG. 7), the connection between the rear body 130, the extension body 124, and the sub skin plate 121 is maintained, and the position is maintained and the main body is maintained. The release of the skin plate 100 is prevented from occurring. That is, the front trunk 110 is shifted from the state shown in FIG.
When the main body 120 is propelled (moved to the left in the figure), the total length of the main skin plate 100 is extended in a nested manner as shown in FIG.

It is the front body 110 that obtains the propulsive force by the operation of the second middle bending jack 52, so that the middle body 120
It is necessary to transmit this propulsion force to the middle body 120 in order to protrude together, and in the illustrated example, as shown in FIG. The other end locking bent portion 113a of the connecting arm 113 having one end fixed can be locked to an appropriate step portion 120a of the middle body 120, and when the front body 110 is propelled, the middle arm 120 is hooked by the connecting arm 113 together. It is designed to be pulled and propelled. The connecting arm 113
The other end of the front body 110 is not fixed to the middle body 120.
Of course, the connecting arm 113 may be modified so that the side of the middle body 120 is fixed and locked on the front side of the front body 110 in order to prevent the middle body 120 from being folded.

If the secondary skin plate 121 does not have sufficient strength to receive the reaction force of the propulsive force from the second bending jack 52, it is appropriately reinforced with a reinforcing member 126 (see FIGS. 6 and 7). I do.

The front body 110 and the middle body 120 are propelled, and the rear end of the middle body 120 is
After passing through the portion of the window hole 123, the branch line shield excavator 2 excavates the branch line tunnel T2 from the window hole 123 of the sub skin plate 121 left at the branch point.

That is, when the front body 110 and the middle body 120 are propelled while leaving the sub-skin plate 121 at the branch point, the window 123 of the sub-skin plate 121 is opened soon (the state of FIG. 3). The branch line shield machine 2 may be started from the window 123. The window 123
In order to open the second middle folding jack 52, a corresponding stroke is required. Therefore, in the present embodiment, a two-stage jack as shown in FIG. 6 is used for the second middle folding jack 52. In the illustrated example, the second middle folding jack 5
2 employs a two-stage set of two wires, but it goes without saying that a jack that extends the rod into a plurality of stages may be employed.

The branch line shield excavator 2 can be the same as the main line shield excavator 1 and can be used in the related art. Therefore, the description thereof is omitted, but the branch line shield excavator 2 is the main line shield excavator 1. It is a matter of course that the main line shield excavator 1 is smaller than the main line shield excavator 1 (in the sub skin plate 121), and the storage place is provided in the second shield jack 54 and the front trunk 110 (not shown). A location that does not interfere with the erector and shearing device is selected.

When the branch line shield excavator 2 is started from the window hole 123 at the branch point and excavation of the branch line tunnel T2 is started carelessly, a dangerous state such as ground collapse occurs. There is a risk. Therefore, before starting the branch line shield machine 2, the window 123
The ground improvement is performed before opening, and the branch line shield excavator 2 is installed in front of the closed window hole 123, and the entrance guide tube (not shown) into which the branch line shield excavator 2 is inserted is provided as a sub-skin. It may be attached to the inner peripheral surface of the plate 121.

Then, when the window hole 123 is opened, excavation is started by the branch line shield excavator 2. At this time, of course, at this time, the reaction force receiver 3 () receives the reaction force of the shield jack of the branch line shield excavator 2. See “Fig. 4”), and temporary support 4
(It may be a segment.)

The main line shield machine 1 after the branch point
In order to perform the excavation, the connection between the front body 110 and the middle body 120 is released, the propulsion force is obtained by the second propulsion jack 54 housed in the front body 110, and the excavation is continued by the conventional method. . In some cases, the reaction force of the second propulsion jack 54 cannot be secured until the branch line shield machine 2 completely comes out of the window hole 123. In this case, the excavation of the main line shield machine 1 is temporarily stopped. When the branch line shield machine 2 completely exits from the window hole 123 as shown in FIG. 4, as shown in FIG.
It is preferable that a segment S or a temporary support (not shown) is assembled in the area 0, and thereafter, the excavation of the main line shield excavator 1 is restarted.

The excavation by the branch line shield excavator 2 may be performed by a conventional method.
When the segment (not shown) of the branch line tunnel T2 becomes long enough to receive the reaction force of the branch line shield machine 2, the reaction force receiver 3 and the temporary support 4 are removed. At this time, the connecting portion between the main line tunnel T1 and the branch line tunnel T2 is surely connected by mortar injection or the like.

[0033]

Since the present invention is as described above, it is possible to provide a branch shield method in which the branch line tunnel T2 can be dug in parallel while the main line tunnel T1 is being dug, and the construction period can be shortened.

In the present invention, since the branch line tunnel T2 can be excavated from the main line tunnel T1, there is no need for a branch shaft as in the conventional branch point shaft system, and the main line shield excavator 1 can be moved to the destination. Since the excavation is performed with the initial outer diameter, it is possible to provide a branch shield construction method in which the diameter of the main tunnel T1 is not significantly reduced in the middle for the conventional multi-circular separation method and the separation method.

[Brief description of the drawings]

FIG. 1 is a cross sectional view of an excavator used in the method of the present invention.

FIG. 2 is a sectional view of a tunnel being excavated by the method of the present invention.

FIG. 3 is a sectional view of the tunnel after the state of FIG. 2 being excavated by the method of the present invention.

FIG. 4 is a sectional view of the tunnel after the state of FIG. 3 during excavation by the method of the present invention.

FIG. 5 is a sectional view of the tunnel after the state of FIG. 4 during excavation by the method of the present invention.

FIG. 6 is a detailed partial cross-sectional view of the rear part of the excavator used in this method.

FIG. 7 is a detailed partial sectional view of a front part of an excavator used in the present construction method.

FIG. 8 is a plan view of a tunnel by a conventional method.

FIG. 9 is a plan view of a tunnel by another conventional method.

FIG. 10 is a front view of a shield machine used in still another conventional method.

FIG. 11 is a plan view of a tunnel excavated by the “FIG. 10” shield machine.

FIG. 12 is a front view of a shield machine used in still another conventional method.

FIG. 13 is a plan view of a tunnel excavated by the “FIG. 12” shield machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main line shield excavator 2 Branch line shield excavator 100 Main skin plate 110 Front trunk 120 Middle trunk 121 Secondary skin plate 123 Window hole 130 Rear trunk T1 Main line tunnel T2 Branch line tunnel

Continuing on the front page (72) Inventor Yoshitaka Kuwahara 1-20-10 Toranomon, Minato-ku, Tokyo Nishimatsu Construction Co., Ltd. (72) Inventor Katsumi Uchida 1-20-10 Toranomon, Minato-ku, Tokyo Nishimatsu Construction Co., Ltd. (58) Investigated field (Int.Cl. ⁶ , DB name) E21D 9/06 301

Claims (1)

(57) [Claims] The main skin plate (100) of the main line shield machine (1) is divided into a front body (110) and a middle body (12).
0) and the rear torso (130) are connected in a folding manner.
A detachable auxiliary skin plate (121) is housed in a double cylindrical shape in the middle body (120), and a branch line shield excavator (2) is housed in the auxiliary skin plate (121). A window hole (123) through which the branch line shield excavator (2) can be started is provided on the peripheral surface of the sub skin plate (121), and the main line shield excavator (1) containing the branch line shield excavator (2) is provided. The thrust is obtained by the operation of the first shield jack (51) housed in the rear trunk (130),
Main line tunnel (T1) with the front torso (110), the middle torso (120) and the rear torso (130) connected to the scheduled branch point
At the branch point, the connection between the middle trunk (120) and the rear trunk (130) is released, and the sub skin plate (121) and the rear trunk (13) are disconnected.
0) at the branch point, and using the sub-skin plate (121) as a reaction force receiving member, to form the second center bending jack (52) between the front trunk (110) and the middle trunk (120). The propulsion force is obtained by the operation, and the excavation of the main line shield excavator (1) is continued while the front body (110) and the middle body (120) are connected, and the front body (110) and the middle body (120) are continued. When the rear end of the inner trunk (120) passes through the window (123) of the sub-skin plate (121) by propulsion, the window (123) of the sub-skin plate (121) left at the branching point. ) Branch line shield excavator (2) and branch line tunnel (T2)
The branch shield method characterized by the fact that it is made to excavate.