JP4854523B2 - Tunnel construction method - Google Patents

Description

  The present invention relates to a tunnel construction method.

  Conventionally, when building a road tunnel or a railway tunnel, to form a widened part with a cross section that is larger than the normal part, (1) install a widening segment ring in the pit with an overexcavated part, and the shield machine passes After that, a method of widening the widening segment ring (see, for example, Patent Document 1), or (2) excavating a natural ground by providing an extra excavation part, and installing the skin plate of the shield machine and the inside of the shield machine There was a method (for example, refer to Patent Document 2) of widening the widening segment ring at the same time.

Japanese Patent Application Laid-Open No. 2004-143917 JP 2004-270356 A

  However, in the method (1), when the widened portion is formed over a long distance, it is necessary to move a large number of widening segment rings. In the method (2), it is necessary to use a shield machine having a special structure.

  The present invention has been made in view of such problems, and the object of the present invention is to use a normal shield machine and reduce the number of widening segment rings to be moved to a minimum, thereby extending the widened portion over a long distance. It is to provide a tunnel construction method that can be formed.

  The present invention for achieving the above-described object is the step (a) of excavating a widening pit provided with an extra digging portion using a shield machine and installing a widening segment in a predetermined range of the widening pit, Installing a joint segment in front of the widening segment, fixing the joint segment and the tail portion of the skin plate of the shield machine, and moving the widening segment toward the outer periphery of the tunnel (c) ), A diameter expansion skin plate disposed on the inner peripheral side of the other widening segment on the end plate provided in the widening segment installed at the foremost part of the predetermined range, and the diameter expansion skin plate A step (d) of fixing a shield jack disposed inside the door, and separating the end plate from the widening segment installed at the foremost portion of the predetermined range While installing a widening at segment inside the expanded skin plate, a tunnel construction method, characterized by comprising a step (e) for advancing the shield machine.

  In the present invention, when the tunnel cross section is returned to normal after forming the widened portion of a predetermined distance, after the step (e), the joint segment and the tail portion of the skin plate are separated and the normal segment is formed inside the skin plate. The normal portion is formed by the step (f) of moving the shield machine forward while installing the.

  The joint segment and the tail portion of the skin plate of the shield machine are fixed using bolts or the like so that they can be easily separated. The end plate is fixed, for example, between the step (b) and the step (c) so that it can be easily separated from the widening segment installed at the forefront of a predetermined range of the widening pit. A bolt or the like is used for fixing.

  In the step (d), a second face plate is fixed to the rear of the face plate installed in the widening segment installed in the foremost part of the predetermined range of the widening pit, and the enlarged skin plate and the shield jack are attached to the second face plate. It is desirable to fix. A bolt or the like is used for fixing.

  In the present invention, first, a widening pit provided with an extra excavation portion is excavated using a shield machine, and a widening segment is installed in a predetermined range of the widening pit. Then, a joint segment is installed in front of the widening segment, and the joint segment and the tail portion of the skin plate of the shield machine are fixed. Next, after the widening segment is moved in the outer circumferential direction of the tunnel, the widening plate disposed on the inner peripheral side of the other widening segments is placed on the end plate provided on the widening segment installed at the forefront of the predetermined range. A diameter skin plate and a shield jack arranged inside the enlarged skin plate are fixed. Thereafter, the end plate is separated from the widening segment installed at the forefront of a predetermined range, and the shield machine is advanced while the widening segment is installed inside the enlarged skin plate.

  According to the present invention, there is provided a tunnel construction method capable of forming a widened portion over a long distance by using a normal shield machine and reducing the number of widening segment rings to be moved to a minimum.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing a state in which the joint segment 27 and the tail portion 15 are fixed. FIG. 1 is a cross-sectional view of the shield machine 3 and the tunnel 2 in the axial direction.

  As shown in FIG. 1, the shield machine 3 includes a skin plate 5, a cutter 7, a copy cutter 9, a shield jack 11, a tail seal 13, and the like. The skin plate 5 is cylindrical, and the cutter 7 is installed on the front end surface of the skin plate 5. The copy cutter 9 protrudes in the outer peripheral direction of the shield machine 3 at the time of use, that is, in the direction indicated by the arrow A in FIG. The excavation cross-sectional area of the shield machine 3 is changed by adjusting the protruding amount of the copy cutter 9 from the cutter 7.

  The shield jack 11 is installed inside the skin plate 5 so as to expand and contract in the axial direction of the tunnel 2. The shield jack 11 advances the shield machine 3 while taking a reaction force from the segments assembled in the skin plate 5. The tail seal 13 is installed on the inner peripheral surface of the tail portion 15 of the skin plate 5. The tail seal 13 maintains the water-stopping property of the tail portion 15 of the skin plate 5.

  In this embodiment, first, a tunnel 2 as shown in FIG. The shield machine 3 assembles the segments inside the tail portion 15 of the skin plate 5 while excavating the normal pit 17 and the widening pit 19 in the natural ground 1.

  In the tunnel 2 shown in FIG. 1, a normal segment ring is installed inside the normal pit 17. The normal segment ring is composed of a plurality of normal segments 21. A plurality of widening segment rings are installed inside a predetermined range 23 of the widening pit 19. The widening segment ring has a widening segment 25. The widening segment 25 is a segment scheduled to move in the outer circumferential direction of the tunnel 2, that is, into the widening pit 19. At least one joint segment ring is installed in front of the widening segment ring. The joint segment ring includes a plurality of joint segments 27.

  In the state shown in FIG. 1, the outer diameters of the normal segment ring, the widening segment ring, and the joint segment ring are substantially the same.

  After the tunnel 2 as shown in FIG. 1 is formed, the joint segment 27 and the tail portion 15 of the skin plate 5 of the shield machine 3 are fixed. For fixing the joint segment 27 and the tail portion 15, a method such as a bolt 35 that can be easily separated is used.

  In addition, the overcutter part 18 is provided in the range 23 in which the widening segment 25 is installed in the widening pit 19 for forming the widening part of the tunnel 2. Since the widening segment 25 after movement is disposed in the overcutter portion 18 (FIGS. 3 to 5), the amount of the overcutter portion 18 is set in consideration of the thickness of the widening segment 25. In order to reduce the amount of excavation of the overcutter portion 18 of the widening pit 19, it is desirable to reduce the thickness of the widening segment 25 as much as possible.

  FIG. 2 is a diagram illustrating a state in which the end plate 29 and the end plate 31 are fixed to the widening segment 25. After the state shown in FIG. 1, as shown in FIG. 2, the end plate 29 is fixed to the inner peripheral surface of the rearmost widening segment 25 a. A bolt, welding, or the like is used for fixing the widening segment 25a and the end plate 29.

  Further, the end plate 31 is fixed to the inner peripheral surface of the foremost widening segment 25b. For fixing the widening segment 25b and the end plate 31, a method such as a bolt 33 with a seal that can be easily separated is used. The end plate 31 is also fixed to the joint segment 27. For fixing the end plate 31 and the joint segment 27, welding or the like may be used.

  FIG. 3 is a diagram showing a state in which the widening segment 25 is moved. After the state shown in FIG. 2, the plurality of widening segments 25 are sequentially moved in the outer peripheral direction of the tunnel 2, that is, in the direction indicated by the arrow A in FIG. For the movement of the widening segment 25, an extrusion device or the like (not shown) installed in the tunnel 2 is used.

  When the widening segment 25 is moved into the widening pit 19, the end plate 29 and the end plate 31 can maintain the water stoppage between the widening segment 25 and the normal segment 21 and between the widening segment 25 and the joint segment 27. It shall have a mechanism.

  FIG. 4 is a view showing a state in which the enlarged skin plate 41 and the shield jack 47 are fixed to the end plate 37. After the state shown in FIG. 3, as shown in FIG. 4, the end plate 37, which is the second end plate and also serves as a ring gutter, is fixed to the rear end surface of the end plate 31. A bolt 39, welding, or the like is used for fixing the end plate 31 and the end plate 37.

  Then, the enlarged skin plate 41 and the shield jack 47 are fixed to the end plate 37. Bolts, welding, or the like is used to fix the end plate 37 to the enlarged skin plate 41 or the shield jack 47.

  Further, a widening segment ring having a widening segment 49 is installed between the end plate 29 fixed to the widening segment 25 a and the shield jack 47.

  The diameter-expanded skin plate 41 has a cylindrical shape and is disposed along the inner peripheral surface of the widening segment ring. A tail seal 45 is provided on the inner peripheral surface of the tail portion 43 of the enlarged skin plate 41. The tail seal 45 keeps the water stoppage of the tail portion 43 of the enlarged skin plate 41.

  The shield jack 47 is disposed inside the enlarged skin plate 41 so as to expand and contract in the axial direction of the tunnel 2. The shield jack 47 advances the shield machine 3 while taking a reaction force from the widening segment ring assembled along the inner peripheral surface of the enlarged skin plate 41.

  FIG. 5 is a diagram showing a state in which the shield machine 3 is dug while assembling the segment ring at the time of widening. After the state shown in FIG. 4, the bolt 33 (FIG. 4) that fixed the widening segment 25b and the end plate 31 is removed, and the widening segment 25b and the end plate 31 are separated.

  When the widening segment 25b and the end plate 31 are separated, the shield machine 3 is connected to the tail portion 15 of the skin plate 5 via the joint segment 27, the end plate 31, and the end plate 37 as shown in FIG. 41, the shield jack 47 is connected.

  As shown in FIG. 5, the shield machine 3 in which the enlarged skin plate 41 and the shield jack 47 are connected via the joint segment 27, the end plate 31, and the end plate 37 causes the copy cutter 9 to protrude from the cutter 7 and the ground 1 While the widening pit 19 is being excavated, the widening segment 49 is assembled inside the tail portion 43 of the enlarged skin plate 41 to form the widened portion of the tunnel 2.

  In the state shown in FIG. 5, in the widening pit 19, a range 50 between the copy cutter 9 and the end plate 31 is filled with a filler or the like (not shown) as necessary. The widening segment 25 is left in the overcutter portion 18 of the widening portion 19.

  FIG. 6 is a diagram illustrating a state where excavation of the widening pit 19 of the tunnel 2 is completed. After excavating the widening pit 19 having a predetermined length, the shield machine 3 expands the diameter while storing the copy cutter 9 (FIG. 5) in the cutter 7 and excavating the normal pit 17 as shown in FIG. The widening segment 49 is assembled in the skin plate 41.

  FIG. 7 is a view showing a state where the joint segment 27 and the tail portion 15 of the skin plate 5 are separated. As shown in FIG. 7, after the shield machine 3 excavates the normal well 17 for the length of the machine and the end plate 31 reaches the front end 20 of the widening pit 19, the bolt 35 (FIG. 6) is removed and the tail of the skin plate 5 is removed. The part 15 and the joint segment 27 are separated.

  FIG. 8 is a diagram illustrating a state in which the normal part of the tunnel 2 is formed. When the tail portion 15 and the joint segment 27 of the skin plate 5 are separated from each other, the shield machine 3 moves from the tail portion 15 of the skin plate 5 to the joint segment 27, the end plate 31, the end plate 37, and the expanded skin as shown in FIG. The plate 41, the shield jack 47, etc. are cut off.

  As shown in FIG. 8, the shield machine 3 from which the joint segment 27, the end plate 31, the end plate 37, the enlarged skin plate 41, the shield jack 47, etc. are cut off is a natural ground with the copy cutter 9 stored in the cutter 7. 1, the normal segment 21 is assembled inside the tail portion 15 of the skin plate 5 while excavating the normal pit 17 to form the normal portion of the tunnel 2. The shield jack 47 is detached from the end plate 37 at an appropriate time after the tail portion 15 and the joint segment 27 are separated.

  Thus, in this embodiment, after the widening segment 25 is moved into the widening pit 19, the enlarged skin plate 41 and the shield jack 47 disposed inside the widening segment ring are replaced with the joint segment 27, the end plate. The widening segment ring having the widening segment 49 is assembled inside the enlarged skin plate 41 by being connected to the tail portion 15 of the normal shield machine 3 through 31 or the like.

  Thereby, when forming the widened part over a long distance, the quantity of the widening segments 25 to be moved can be reduced to the minimum. Further, the widened portion of the tunnel 2 can be formed by only a simple operation of fixing the member to the normal shield machine 3.

  Further, after the formation of the widened portion, the joint segment 27, the end plate 31, the enlarged skin plate 41, the shield jack 47 and the like are separated from the tail portion 15 of the shield machine 3, and the normal segment ring is assembled inside the skin plate 5. . Thereby, the cross section of the tunnel 2 can be returned to normal only by a simple operation of separating the member from the shield machine 3.

  In the present embodiment, the bolt 35 is used for fixing the tail portion 15 of the skin plate 5 and the joint segment 27, and the bolt 33 is used for fixing the widening segment 25b and the end plate 31, but these portions are It may be fixed by other methods that can be easily fixed or separated. In the present embodiment, the end plate 37 is provided as the second end plate, but the second end plate may not be provided.

  1 to 8 show the widening pits 19 provided with the digging portions on both sides of the normal pit 17, the position where the digging portions are provided is not limited to this. For example, an extra excavation part may be provided in only one place of the normal pit 17.

  As mentioned above, although preferred embodiment of the tunnel construction method concerning this invention was described referring an accompanying drawing, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

The figure which shows the state which fixed the joint segment 27 and the tail part 15. The figure which shows the state which fixed the end plate 29 and the end plate 31 to the segment 25 for widening The figure which shows the state which moved the segment 25 for widening The figure which shows the state which fixed the diameter expansion skin plate 41 and the shield jack 47 to the end plate 37 The figure which shows the state which is digging the shield machine 3 while assembling the segment ring at the time of widening The figure which shows the state which finished excavation of the widening pit 19 of the tunnel 2 The figure which shows the state which cut | disconnected the joint segment 27 and the tail part 15 of the skin plate 5. FIG. The figure which shows the state which forms the normal part of the tunnel 2

Explanation of symbols

1 ……… Machiyama 2 ……… Tunnel 3 ……… Shield machine 5 ……… Skin plate 11, 47 ……… Shield jack 15, 43 ……… Tail 17 ……… Normal mine 19 ……… Wide expansion Bore 21 ......... Normal segment 23 ......... Range 25 ......... Wide-width segment 27 ......... Joint segment 29, 31, 37 ......... Tail plate 33, 35, 39 ......... Bolt 41 ......... Expanded skin Plate 49 ……… Wide segment

Claims (4)

Using a shield machine, excavating a widening pit provided with a surplus digging portion, and installing a widening segment in a predetermined range of the widening pit,
A step (b) of installing a joint segment in front of the widening segment and fixing the joint segment and the tail portion of the skin plate of the shield machine;
A step (c) of moving the widening segment toward the outer periphery of the tunnel;
On the end plate provided on the widening segment installed at the forefront of the predetermined range, on the inner diameter side of the other widening segment, an enlarged skin plate, and inside the enlarged skin plate A step (d) of fixing a shield jack to be disposed;
Separating the end plate from the widening segment installed at the forefront of the predetermined range, and advancing the shield machine while installing the widening segment inside the enlarged skin plate (e);
The tunnel construction method characterized by comprising.   2. The method according to claim 1, further comprising a step (f) of separating the joint segment and a tail portion of the skin plate, and advancing the shield machine while installing a normal segment inside the skin plate. Tunnel construction method.   2. The tunnel construction according to claim 1, wherein the end plate is installed in the widening segment installed at the foremost part of the predetermined range between the step (b) and the step (c). Method.   2. The tunnel according to claim 1, wherein in the step (d), a second face plate is fixed behind the face plate, and the enlarged skin plate and the shield jack are fixed to the second face plate. Construction method.

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