JPH0768858B2 - Construction method of large-section shield tunnel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a large-section shield tunnel, and more particularly to a method for constructing a large-section shield tunnel for safely and economically constructing a large-section shield tunnel.

[0002]

2. Description of the Related Art Conventionally, when constructing a shield tunnel having a super-large cross section, for example, a method of excavating and constructing a super-large cross section at once using one super-large cross section hermetic mechanical shield has been adopted.

[0003]

However, the above-mentioned prior art has the following problems.

(1) Since the shield machine becomes extremely large, the number of divisions of the machine body increases. Therefore, transportation,
It takes time to assemble. Also, it takes a lot of time to dismantle the super-sized shield machine when the tunnel excavation is reached. Therefore, the whole construction period becomes long. (2) If the shield machine becomes extremely large, it will take many days and cost to manufacture the machine. (3) Of course, the segment included in the super-large shield machine also becomes large, and the segment becomes expensive. (4) Even if one piece of a large-sized segment is used as the maximum weight for transportation, the number of divisions is large, so that it takes time and money to transport. (5) The amount of excavated earth and sand generated by day and night work of the ultra-large shield machine becomes extremely large, and a large number of dump trucks are required to carry the earth and sand, which causes a traffic obstacle. (6) In the case of a super-large sealed mechanical shield, a large amount of electric power is required for excavation, and thus a large electric power facility is required. (7) Since it is necessary to excavate a large-width cutting face at once, it becomes difficult to stabilize the cutting face.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to carry out construction by using a small cross section shield machine, and to use a small electric equipment, which is safe and economical. An object of the present invention is to provide a method for constructing a large-section shield tunnel capable of constructing a shield tunnel having a cross section.

[0006]

To achieve the above object, the present invention provides a small-section shield tunnel 1 having a substantially rectangular section.
The annular lining body 2 is constructed by constructing 2, 3, ... In such a manner that low-strength backing material or cast-in-place concrete 18 is overlapped in the adjacent portion.
0 is formed, and then the segments 17 of the side wall portions of the adjacent small cross-section shield tunnels 1, 2, 3, ... Are sequentially removed, and the backing material or the cast-in-place concrete 18 between the segments 17, 17 is removed. Then, the tunnels 23 are formed through the side wall portions of the small-section shield tunnels 1, 2, 3, ... Adjacent to each other, and in parallel with this or after the tunnels are formed, the structural material or the reinforcing material 24, 25 is formed in the tunnel 23. Then, concrete 28 is placed in the tunnel 23, and after hardening of the concrete 28, the annular lining body 20
The earth and sand in the inside are excavated and discharged to construct a tunnel 31 having a large cross section.

[0007]

In the present invention, a large number of small-section shield tunnels 1, 2, 3, ... Of substantially rectangular section are constructed. At this time, the small-section shield tunnels 1, 2, 3, ... Are constructed by stacking backfill material or cast-in-place concrete 18 at adjacent portions to form an annular lining body 20 including a completed cross-section 21. .

After that, the segments 17 on the side walls of the adjacent small cross section shield tunnels 1, 2, 3, ... Are sequentially removed. In addition, the small-section shield tunnels 1, which are adjacent to each other,
The backing material or cast-in-place concrete 18 between the segments 17, 17 of 2, 3, ... Is removed to form a tunnel 23 that penetrates the side walls of the small-section shield tunnels 1, 2, 3 ,.

In parallel with the formation of the tunnel 23 or after the formation of the tunnel 23, structural materials or reinforcing materials 24 and 25 are installed in the tunnel 23, and then concrete 28 is placed in the tunnel 23 to form an annular lining. Give the body 20 the necessary strength.

After the concrete 28 is hardened, the earth and sand (ground material G) in the annular lining body 20 is excavated and discharged to construct a tunnel 31 having a large cross section.

As described above, in the present invention, the annular lining body 20 including the completed cross section 21 is constructed by connecting a large number of small cross section shield tunnels 1, 2, 3, ... Construction can be done using a shield machine, therefore there is less temporary equipment, the construction yard can be smaller, a small power facility is sufficient, and the face can be easily stabilized.

Further, since it is not necessary to use a large shield machine, the construction can be carried out safely. Moreover, the shield machine can be transported and assembled in a short time, the shield machine can be disassembled in a short time when the tunnel excavation is reached, the number of days and cost for manufacturing the machine can be reduced, and the segment included in the shield machine can be small in size. In combination with cost reduction, weight reduction, and cost reduction, it becomes possible to construct a large-section tunnel economically.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an example of an annular lining body including a completed cross section, FIGS. 2 and 3 are views showing a process of constructing the annular lining body, and FIGS. It is a figure which shows the excavation process of the small cross section shield tunnel which is doing.

First, according to the method of the present invention, a large number of small-section shield tunnels 1, 2, 3, ...
Although 16 is built by one or a plurality of shield machines, this embodiment shown in FIGS. 2 and 3 shows an example of building by one shield machine.

As can be seen from FIGS. 2 and 3, small-section shield tunnels 1, 3, 5, ...
Build every other piece. Each small section shield tunnel 1,
.. are formed of a segment 17 and a backfill material or cast-in-place concrete 18 that encloses the segment 17, and the inside of the segment 17 is a pit 19. The segment 17 is fastened so that it can be assembled and disassembled from the inside of the tunnel with bolts and nuts. The backfill material or cast-in-place concrete 18 is a non-reinforced concrete having a low strength, a uniaxial compressive strength of about 10 to 50 kgf / cm ^2, and a thickness considerably thicker than a tail void generated by a usual shield construction method. ing. The reason is shown in Figure 3.
As shown in, other small cross section shield tunnels 4, 6, ... are built between every other small cross section shield tunnels 1, 3, 5, ..., and adjacent small cross section shields are connected to each other. This is because, when the annular lining body 20 is constructed, the backing material or the cast-in-place concrete 18 overlap each other to facilitate connection.

The small cross section shield tunnels 1, 3, 5,
For example, when the small cross section shield tunnel 1 is explained, as shown in FIGS. 4 and 5, the small cross section shield machine 100 excavates and builds. The small cross section shield machine 100 includes a shield outer cylinder 101, an earth discharging device 102 such as a screw conveyor, a propulsion jack 103,
Lining concrete pressure jack 1 having pressure plate 105
04, a concrete press-fitting pipe 106 having a concrete press-fitting port 107, an in-machine backfill injection pipe 108, and a tail portion 109 that determines the thickness of the backfill material or cast-in-place concrete 18.

Then, the rectangular small-section shield machine 10 is used.
At 0, the mountain retaining segment 17 and the shield outer cylinder 10
Between 1 is wide open to take the thickness of the backfill or cast-in-place concrete 18. Then, in this small-section shield machine 100, a reaction force is applied to the segment 17, and the shield outer cylinder 101 is propelled by the propulsion jack 103 to excavate the natural ground G. The excavated earth and sand is carried to the rear of the small cross section shield machine 100 by the earth discharging device 102 and discharged. At the same time as the promotion of the shield machine, segment 1
A low-strength concrete is press-fitted into the space between the shield tube 7 and the shield outer cylinder 101 through the concrete press-fitting pipe 106 and the concrete press-fitting port 107, and is poured as backfill material or cast-in-place concrete 18. At that time, segment 17
And the shield outer cylinder 101, the backing material or the cast-in-place concrete 18 press-fitted is blocked by a pressure plate 105 so as not to enter the shield machine. Further, the segment 17 and the shield outer cylinder 10 are provided by the lining concrete pressure jack 104 via the pressure plate 105.
Pressure is applied until the backfill material or the cast-in-place concrete 18 placed in the space between the ones is hardened to prevent the ground G from collapsing and then proceed with the excavation. Furthermore, behind the tail portion 109 thickened according to the thickness of the backfill material or cast-in-place concrete 18, the backfill material or cast-in-place concrete of low strength is used by using the in-machine backfill injection pipe 108 together with the propulsion of the shield machine. Place 18

By repeating the above work,
After building small-section shield tunnels 1, 3, 5, ... Every other one, by the same work, between the small-section shield tunnels 1, 3, 5, ..., Other small-section shield tunnels 2, 4, ... Are successively built, and the backing material or the cast-in-place concrete 18 of adjacent small cross section shield tunnels are overlapped, and as shown in FIG. 1, small cross section shield tunnels 1, 3, 5, ... , 16 are connected to each other to construct an annular lining body 20 which is an integral structure including a rectangular completed cross section 21 in this embodiment.

Next, FIG. 6 is a diagram showing a process of connecting the small cross section shield tunnels forming the annular lining body, FIG. 7 is a cross sectional view taken along the line AA of FIG. 6, and FIGS. FIG. 10 is a diagram showing a process of connecting a small cross section shield tunnel following FIG.
FIG. 4 is a cross-sectional view showing an example of a completed large-section shield tunnel. As mentioned above, small-section shield tunnel 1,
After constructing the annular lining body 20 in which 2, 3, ..., 16 are connected, the small-section shield tunnels 1, 2, 3, ..., 16 are connected in series. At that time, as shown in FIGS. 6 and 7, first, for example, every other segment 17 interposed between adjacent small cross-section shield tunnels 22 is removed,
Partially remove it. Next, the low-strength backfill material or cast-in-place concrete 18 that is placed between the adjacent small-section shield tunnels 22, that is, the lining concrete is excavated by manpower or mechanical force, and adjacent small-section shields A tunnel 23 penetrating the side walls of the tunnels 1, 2, 3, ..., 16 is formed.

Then, as shown in FIG. 8, vertical and horizontal structural members or reinforcing members 2 for holding the tunnel 23.
Install 4,25. This structure or reinforcement 24,2
For 5, a reinforcing bar, a steel frame, a PC steel wire or the like is used. Further, the structural material or the reinforcing material 24, 25 may be installed by penetrating the segment 17, or the segment 17 interposed between adjacent small cross section shield tunnels may be partially removed and installed.

Further, as shown in FIG. 8, molds 26 are installed in the tunnel 23 at predetermined intervals.

Next, as shown in FIGS. 8 and 9, concrete 28 is placed in an area 27 partitioned by the mold 26.
To place. Although not shown in the drawing, formwork is also installed at predetermined intervals at the starting point and reaching point of the shield tunnel, and concrete is placed in the area partitioned by the formwork. A working space 27 'is formed outside the area 27. However, the working space 27 '
After use, fill with concrete 28. Further, the area 2
Before the concrete 28 is placed in the inside of the 7, if necessary, a formwork for forming a passage, a conduit 30 for electric power, communication, etc. (see FIG. 10).
(See). After the concrete 28 cast in the area 27 is hardened, the form 26 is removed.

As shown in FIG. 10, however, the annular lining body 20 constructed by a series of small-section shield tunnels 1 to 16 is finished to have a required strength by using structural materials or reinforcing materials 24 and 25 and concrete 28. After the passage 29 for work and drainage and the pipeline 30 for electric power and communication are provided at necessary places, the earth and sand inside the annular lining body 20, that is, the ground G in this embodiment, is removed. Drilled by the usual method,
The earth and sand are discharged, and in this embodiment, a large section tunnel 31 having a rectangular completed section 21 is constructed. Incidentally, the backing material or the cast-in-place concrete portion can be removed on the inside in order to secure an inner cross section.

Then, as described above, the annular lining body 2 is formed by forming the small-section shield tunnels 1 to 16 by overlapping the backfill material or the cast-in-place concrete 18 at the adjacent portions.
Construction of 0 → Partial removal of segment 17 between adjacent small-section shield tunnels → Removal of backfill material or cast-in-place concrete 18 between adjacent small-section shield tunnels 22 and adjacent small-section shield tunnels Construction of the tunnel 23 formed through the side wall of the structure → Installation of structural materials or reinforcements 24 and 25 → Installation of the formwork 26 in the tunnel 23 → Installation of concrete 28 in the area 27 partitioned by the formwork 26 Placing → Excavation of the natural ground G inside the annular lining body 20 and discharge work to the arrival point of the tunnel makes it possible to construct the large-section tunnel 31 safely and economically.

As described above, by the rectangular small cross section shield machine,
The method of constructing a rectangular large-section shield tunnel has been described. According to the constructing method of the present invention, a large-section shield tunnel is constructed by connecting a plurality of shield tunnels having a substantially rectangular cross section in the vertical direction and / or the left-right direction. It is also possible to construct a large cross section shield tunnel having a modified cross section other than a rectangular cross section.

[0026]

As described above, according to the method of the present invention, small-section shield tunnels 1, 2, 3, ... Of substantially rectangular cross-section are constructed such that low-strength backing materials or cast-in-place concrete 18 are overlapped at adjacent portions. To form the annular lining body 20, and then sequentially remove the segments 17 of the side walls of the small-section shield tunnels 1, 2, 3, ... Adjacent to each other, and at the same time, backing material or place between the segments 17, 17. Pouring concrete 18
Of small cross section shield tunnels 1, 2
A tunnel 23 penetrating the side wall portions of 3, ... Is formed, and in parallel with this or after the tunnel is formed, structural materials or reinforcing materials 24 and 25 are installed, and then concrete 28 is poured into the tunnel 23. Since the concrete 28 is hardened and the earth and sand in the annular lining body 20 is excavated and discharged to construct the tunnel 31 having a large cross section, it can be constructed using a small cross section shield machine. There are advantages that the equipment is small, the construction yard is small, a small electric power equipment is sufficient, and the face can be easily stabilized. In addition, the construction of the annular lining body 20
Since the backing material used for manufacturing has low strength,
It can be easily cut and the excavation speed will not slow down.
Yes.

Further, since the method of the present invention does not require the use of a large shield machine, it has the effect of being able to carry out the work safely, and in addition, the shield machine can be transported and assembled in a short time, and when the tunnel excavation is reached. The shield machine can be disassembled in a short time, the number of days and cost for manufacturing the machine can be reduced, and the segment included in the shield machine can be downsized.
Combined with the reduction in weight and cost, it has the effect of being able to construct a large cross-section tunnel economically.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an annular lining body including a completed cross section.

FIG. 2 is a diagram showing a process of constructing the annular lining body shown in FIG.

FIG. 3 is a diagram showing a process of constructing the annular lining body subsequent to FIG.

FIG. 4 is a diagram showing an excavation process of a small cross section shield tunnel which constitutes an annular lining body.

FIG. 5 is a diagram showing an excavation process of the small cross-section shield tunnel following FIG. 4;

FIG. 6 is a diagram showing a process of connecting small cross-section shield tunnels forming an annular lining body.

7 is a cross-sectional view taken along the line AA of FIG.

FIG. 8 is a diagram showing a process of connecting the small cross section shield tunnels following FIG. 6;

FIG. 9 is a diagram showing a process of connecting the small cross-section shield tunnels following FIG. 8;

FIG. 10 is a sectional view showing an example of a completed large-section tunnel.

[Explanation of symbols]

1-16 Small-section shield tunnel 17 Segment 18 Backfill material or cast-in-place concrete 20 Annular lining body 21 Completed section 22 Between adjacent shield tunnels 23 Phases Formed through the side wall between adjacent small-section shield tunnels Tunnels 24, 25 Structural or reinforcing materials 26 Formwork 27 Areas partitioned by formwork 28 Concrete 31 Completed large-section tunnel 100 Small-section shield machine 101 Shield outer cylinder 102 Earth-moving device 103 Propulsion jack 104 Lining concrete addition Pressure jack 105 Pressure plate 106 Concrete press fit pipe 108 Inside backfill injection pipe 109 Tail part of shield outer cylinder

Claims (1)

[Claims] 1. An annular lining body 20 is formed by constructing small-section shield tunnels 1, 2, 3, ... Of substantially rectangular cross-section so that low-strength backfill material or cast-in-place concrete 18 is overlapped at adjacent portions. Then, while sequentially removing the segments 17 of the side wall portions of the small-section shield tunnels 1, 2, 3, ... Which are adjacent to each other, the backing material or cast-in-place concrete 18 between the segments 17 and 17 is removed, and the adjacent segments are adjacent to each other. The tunnel 23 that penetrates the side walls of the small-section shield tunnels 1, 2, 3, ... Is formed, and in parallel with this or after the tunnel is formed, the structural material or the reinforcing material 24, 25 is formed in the tunnel 23.
Then, concrete 28 is placed in the tunnel 23, and after hardening of the concrete 28, the annular lining body 2
A method of constructing a large-section shield tunnel, which comprises digging and discharging earth and sand in 0 to construct a large-section tunnel 31.