JP5388786B2 - How to build a tunnel - Google Patents

Description

  The present invention relates to a method for constructing a tunnel having a tunnel widening portion such as a junction, a branching portion, or an emergency parking zone such as a road tunnel.

  The present applicant has proposed a technique for constructing a widened portion in a tunnel cross section using a shield machine provided with a widening cutter that can protrude from the peripheral surface of the main body (see Patent Document 1).

  In addition, the present applicant has proposed a technology for constructing a junction between a main tunnel and a branch tunnel (see Patent Document 2). Specifically, in the section of the junction, the main tunnel and the branch tunnel are dug so as to be close to each other, and a substantially circular lining including a segment with a protrusion at the upper part and the lower part is assembled. Next, the projections of the segments with projections are extruded to form projections on the upper and lower portions of the main tunnel and the branch tunnel. Then, a steel shell is attached so as to be bridged between these protrusions, and the space between the steel shell and the lining is filled with a filler to integrate the lining of the main tunnel and the branch tunnel. And the envelope of the cross section of the lining consisting of the branch tunnel and steel shell is constructed so as to be almost circular. According to this, without cutting from the ground, it is not necessary to devise the shield machine, and it is possible to reduce their costs. In addition, the merging part of the shield tunnel can be constructed while using the merged main tunnel.

JP 2005-54528 A JP 2008-14076 A

  By the way, an error in the tunnel length direction, an error in the tunnel width direction, an error in the vertical direction, and an error due to rolling occur between the main tunnel and the branch tunnel.

  The subject of this invention is providing the construction method of the tunnel which can adjust easily the difference | error between a main line tunnel and a branch tunnel in the widening part and confluence | merging part of a tunnel.

  In order to solve the above-mentioned problems, the invention described in claim 1 is a tunnel construction method, in which a hollow portion is formed by excavating the underground between the main tunnel and the branch tunnel lining that are dug in parallel. After forming, a connecting segment is arranged between the main line tunnel and the upper lining segment of the branch tunnel, and a connecting segment is arranged between the main line tunnel and the lower lining segment of the branch tunnel, and the lining A gap is provided between the segments and the opposing end faces of the connecting segment so that the interval between the upper end portions is wider than the interval between the lower end portions. Drop the adjusting plate that has end portions parallel to the end faces of the segments, and then place concrete between the lining segment and the connecting segment And wherein the Rukoto.

  A second aspect of the present invention is the tunnel construction method according to the first aspect, wherein a plurality of grooves are provided on the end surfaces of the two segments in the vertical direction, and the end portions of the adjusting plate are engaged with the grooves. It is characterized by making it.

  The invention according to claim 3 is the tunnel construction method according to claim 1 or 2, characterized in that the lining segment and the connecting segment are connected by a reinforcing bar.

  ADVANTAGE OF THE INVENTION According to this invention, the error between a main line tunnel and a branch line tunnel can be easily adjusted in the widening part and confluence | merging part of a tunnel.

The structure of one Embodiment to which this invention is applied is shown, and it is the schematic front view which showed the integrated lining of the tunnel merge part. It is explanatory drawing which shows the construction method of a tunnel junction part. It is explanatory drawing which shows the construction method of a tunnel junction part. It is explanatory drawing which shows the construction method of a tunnel junction part. It is an enlarged view of the junction part 10 of the general segment 6 and the connection segment 9. FIG. FIG. 6 is a view on arrow VI in FIG. 5.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 shows an integrated lining of a tunnel junction as a configuration of an embodiment to which the present invention is applied. As shown in the figure, the tunnel junction is composed of a general segment 2 on one side that constitutes the main tunnel 1 and an opposite side that constitutes a ramp tunnel 5 that is a branch tunnel that is dug in parallel to the main tunnel 1. The general segment 6 and a general segment 2 and a connecting segment 9 that connects the upper and lower sides of the general segment 6. The general segment 2, the general segment 6, and the connection segment 9 are joined by a joint 10.

The construction method of the tunnel junction will be described below. First, as shown in FIG. 2, the main tunnel 1 is formed in the ground. At this time, the main tunnel is formed from the general segment 2 and the cutting segment 4. The cutting segment 4 is thinner than the general segment 2. The cutting segment 4 is made of a material that can be excavated by a cutter of a shield excavator that excavates the ramp tunnel 5.
Next, the partition segment 3 is installed between the upper and lower general segments 2, and an internal support (not shown) is installed in the space between the partition segment 3 and the general segment 2. In addition, the partition segment 3 is installed in the position which is not cut by the cutter of the shield excavator which excavates the ramp tunnel 5 mentioned later.
Next, the backfill material 16 is backfilled into the space between the partition wall segment 3 and the cutting segment 4.

  Next, as shown in FIG. 3, the ramp tunnel 5 is formed in the ground. At this time, the ramp tunnel 5 is formed from the general segment 6 and the removal segment 8. The cutting segment 4 is cut by a cutter of a shield excavator that excavates the ramp tunnel 5. Thereafter, an internal support and a work gantry (not shown) are also installed inside the lamp tunnel 5.

  Next, although not shown in the figure surrounding the lining of the main tunnel 1 and the lamp tunnel 5, a water-stopping chemical injection is performed in advance from the inside of the main tunnel 1 and the inside of the lamp tunnel 5. Similarly, a water-stopping chemical injection is performed in advance in the ground between the main tunnel 1 and the ramp tunnel 5. Alternatively, the ground surrounding the lining of the main tunnel 1 and the ramp tunnel 5 may be improved by a freezing method.

  Next, a part of the upper removal segment 8 is removed. Next, the upper ground between the linings of the main tunnel 1 and the ramp tunnel 5 is excavated to form a cavity for installing the connecting segment 9.

Next, as shown in FIG. 4, in the ceiling of the excavated upper cavity, a support work (not shown) is formed by long steel pipe fore-piling construction, and the connecting segment 9 is arranged at the lower part of the support work. Thereafter, the general segments 2 and 6 and the connecting segment 9 are connected.
Similarly, the general segments 2 and 6 and the connecting segment 9 are connected at the bottom of the excavated cavity.

  Thereafter, the internal support work, the work gantry, the removal segment 8 and the bulkhead segment 3 are completely removed. Thus, the widened portion of the tunnel is constructed as shown in FIG.

Here, a connection structure between the general segment 6 and the connecting segment 9 will be described.
FIG. 5 is an enlarged view of the joint portion 10 between the general segment 6 and the connecting segment 9, and FIG. As shown in FIG. 5, the opposing surfaces of the general segment 6 and the connecting segment 9 are inclined. In the general segment 6 and the connecting segment 9, the interval between the upper end portions is wider than the interval between the lower end portions. In the upper connection segment 9, the tunnel outer side is the upper side, but in the lower connection segment, the tunnel inner side is the upper side.

  Further, as shown in FIG. 6, a plurality of grooves 71 and 72 are provided in the vertical direction on the opposing surfaces of the general segment 6 and the connecting segment 9. The widths of the grooves 71 and 72 are constant, and are provided at regular intervals in the length direction of the tunnel.

  A plurality of adjustment plates 73 are arranged between the facing surfaces of the general segment 6 and the connecting segment 9. The adjustment plate 73 is a wedge-shaped steel plate, and the upper and lower sides of the adjustment plate 73 are parallel. The non-parallel two sides of the adjustment plate 73 are parallel to the end surfaces of the general segment 6 and the connecting segment 9, respectively, and are fitted in the grooves 71 and 72, respectively.

The general segment 6 and the connecting segment 9 are connected by a reinforcing bar 77 at the lower part of the opposing end.
Concrete 20 is placed in the gap between the general segment 6 and the connecting segment 9 so that the cover thickness of the adjusting plate 73 and the reinforcing bar 77 is sufficient.

  Hereinafter, the connection method of the general segment 6 and the connection segment 9 is demonstrated. First, in the opposing part of the general segment 6 and the connection segment 9, the tunnel inner parts of the opposing edge part are connected by the reinforcing bar 77. Next, the adjustment plate 73 is dropped into the grooves 71 and 72 from above at the facing portion between the general segment 6 and the connecting segment 9. Thereafter, concrete 20 is placed between the general segment 6 and the connecting segment 9.

  In addition, since the joining structure of the general segment 2 and the connection segment 9 is the same as the joining structure of the general segment 6 and the connection segment 9, description is omitted.

  Here, a method for absorbing an error between the main tunnel 1 and the lamp tunnel 5 according to the present invention will be described. Between the main tunnel 1 and the ramp tunnel 5, an error in the tunnel length direction, an error in the tunnel width direction, an error in the vertical direction, and an error due to rolling are generated.

  In the present invention, the error in the tunnel length direction can be adjusted by shifting the relative positions of the grooves 71 and 72 into which the adjustment plate 73 is fitted in the tunnel length direction. The error in the tunnel width direction can be adjusted by shifting the positions of the general segment 6 and the connecting segment 9 in the width direction and shifting the position of the adjustment plate 73 in the vertical direction. Similarly, errors in the vertical direction and errors due to rolling can be adjusted by shifting the positions of the general segment 6 and the connecting segment 9.

  As described above, in the lining of the main tunnel 1 and the ramp tunnel 5, after excavating the underground between them and excavating the underground of the upper and lower general segments 2 and 6 to form the cavity, By connecting the connecting segments 9 between the general segments 2 and 6, respectively, it is possible to construct an elliptical tunnel junction that is resistant to external pressure as shown in FIG. it can.

  In the above embodiment, one adjustment plate 73 is fitted into one groove 71, 72. However, the present invention is not limited to this, and a plurality of sheets are provided in one groove 71, 72. The adjustment plate 73 may be fitted. Further, a plurality of protrusions are provided on the end face of the general segment 6 of the adjustment plate 73 and a face parallel to the end face of the connecting segment 9 at intervals equal to the intervals of the grooves 71, 72. May be fitted into the plurality of grooves 71, 72.

1 Main tunnel 2, 6 General segment 4 Cutting segment 5 Branch line tunnel 8 Removal segment 9 Connection segment 20 Concrete 71, 72 Groove 73 Adjustment plate 77 Reinforcing bar

Claims (3)

After excavating the ground between the lining of the main line tunnel and the branch line tunnel excavated substantially in parallel, a connecting segment is arranged between the lining segments at the upper part of the main line tunnel and the branch line tunnel. , A connecting segment is arranged between the main line tunnel and the lining segment under the branch line tunnel,
Between the opposing end surfaces of the lining segment and the connecting segment, a gap is provided so that the interval between the upper end portions is wider than the interval between the lower end portions,
An adjustment plate having both end portions parallel to the end face of the lining segment and the end face of the connecting segment is dropped into the gap,
Then, concrete is cast between the lining segment and the connecting segment, and the tunnel construction method is characterized. A plurality of grooves are provided in the vertical direction on the end surfaces of the two segments,
The tunnel construction method according to claim 1, wherein an end portion of the adjustment plate is engaged with the groove.   The tunnel construction method according to claim 1, wherein the lining segment and the connection segment are connected by a reinforcing bar.

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