JP4374535B2 - Tunnel construction method - Google Patents

Description

  The present invention relates to a tunnel construction method, and more particularly to a tunnel construction method capable of efficient construction using a full-section tunnel excavator such as a tunnel boring machine.

  As is well known, when a tunnel is constructed by a full-section tunnel excavator such as a tunnel boring machine (TBM), the lining on the excavated wall surface is generally performed by placing concrete on the site. As an example, for example, in Patent Document 1, concrete is first placed on the arch part, and the lining part of the arch part is preceded, and then concrete is placed on the invert part to cover the invert part. A construction method of performing construction is disclosed.

As a method for conveying excavated soil in this type of tunnel construction method, for example, Patent Document 2 proposes a method using a stretch belt conveyor.
JP 2001-173386 A Japanese Patent Laid-Open No. 10-280883

  However, as shown in Patent Document 1, by placing concrete in the invert part and performing the lining, not only the construction period is long but also a complicated and special formwork device is required, so it is not always efficient. It is not something that can be done. In this type of tunnel construction method, there are cases where segments are used in the same way as the shield method, and workability can be improved if lining is performed by assembling the segments all around the tunnel. However, since a significant increase in construction cost is unavoidable, it cannot be widely adopted.

  Further, when the excavated soil is transported by the stretching belt conveyor, it is more efficient than, for example, the case of truck transportation. Conventionally, as shown in Patent Document 2, the excavator and the stretching belt conveyor are used. A mobile belt conveyor is installed between them and the excavated soil from the excavator is transported to the stretching belt conveyor via the mobile belt conveyor, so the mobile belt conveyor is refilled as it digs. Therefore, it is not always possible to efficiently carry excavated soil.

  In view of the above circumstances, the present invention can efficiently cover the invert part while avoiding an increase in construction cost, and enables more efficient transport of excavated soil by a stretch belt conveyor. The purpose is to provide a reasonable tunnel construction method.

The present invention relates to a tunnel construction method for lining a drilling wall surface by advancing a full-section tunnel excavator while advancing a lining device group following the excavation behind the full-section tunnel excavator. The excavated soil loading trolley equipped with the tail pulley is placed behind the full-section tunnel excavator, the excavated soil is loaded into the excavated soil throwing cart and continuously conveyed to the wellhead by the stretch belt conveyor, and the excavation is followed The stretch belt conveyor is extended by advancing the excavated soil throwing cart, the lining device group is arranged behind the excavated soil throwing cart, and the lining device group is excavated together with the excavated soil throwing cart. By moving it forward and following it, an invert segment is installed for the invert part, and behind it, It is an basic that they would Da設formed continuously arch concrete as Kokabe to invert the segment.

In the present invention, as the lining device group, an erector that installs an invert segment in the invert part, a sheet pasting cart that affixes a sheet material on the excavation wall surface of the arch part, and a reinforcing bar is arranged on the pasted sheet. Adopting a bar arrangement and a movable formwork device with the formwork facing the arch , the invert segment is constructed behind the excavated sediment loading trolley by the erector, and these lining equipment groups have already been constructed. It is characterized in that it is arranged in that order on the invert segments of this and is advanced in synchronization .

  In the present invention, a roadbed is preferably constructed on the invert segment, and the lining device group is arranged on the roadbed and advanced.

  In the present invention, an excavating soil continuous loader and a quantitative feeder are arranged between the full-section tunnel excavator and the excavated soil loading cart, and the excavated soil excavated by the full-section tunnel excavator is continuously loaded. It is preferable that a fixed amount is continuously fed into the excavated soil loading cart by the machine and the quantitative feeder, and the continuous loading machine and the quantitative feeder are moved forward along with the excavating soil loading cart.

  In the present invention, prior to excavation by the full-section tunnel excavator, a small-diameter pilot tunnel is excavated at the center of the excavation section, and the excavation cross section to be excavated by the full-section tunnel excavator is obtained by work from the inside of the pilot tunnel. It is recommended to improve the water stop for the outer ground and then expand the diameter of the pilot tunnel by excavating a full-section tunnel excavator and excavating the surrounding ground of the pilot tunnel in an annular shape.

  According to the present invention, not only can the inverted portion be lined up early by the segment, but it can be used as a work roadbed to start the arched portion at an early stage for efficient lining work. As a result, the construction efficiency of the lining work can be greatly improved, and the uncovered section can be shortened. Since only the invert part of about 1/3 of the entire circumference of the tunnel is covered with the segment, the cost increase can be sufficiently suppressed as compared with the case where the segment is installed over the entire circumference as in the shield method. . Therefore, the present invention has both the advantages of excellent workability by segment lining and economical efficiency of lining by cast-in-place concrete, and is particularly suitable for application to construction of large-section and long-sized tunnels.

  In addition, as the lining equipment group, conventional arch concrete construction means other than the erector for installing the invert segment can be adopted as they are, and efficient lining work can be carried out by the conventional work procedure. it can.

  In addition, by constructing the roadbed on the invert segment and arranging the lining device group on the roadbed and moving it forward, the roadbed can be installed early, and a stable workbed for lining work can be created. It can be secured early and is more efficient.

  In addition, the excavated soil can be transported with a stretch belt conveyor, enabling efficient excavated soil transport. The stretching belt conveyor can be naturally stretched without requiring a troublesome replacement work or the like by simply moving them forward following the excavation. In addition, it is not necessary to employ a special full-section tunnel excavator in order to employ the stretch belt conveyor, or to add a special configuration for that purpose to the full-section tunnel excavator.

  Furthermore, prior to excavation of the main tunnel, the pilot tunnel is pre-excavated and the water stop is improved in advance around it, so that the full-section tunnel excavator itself is not required to have a high level of water stop performance. Even when constructing a large section tunnel in an aquifer, it is possible to adopt a full section tunnel excavator with a relatively simple structure such as an open tunnel boring machine.

  One embodiment of the tunnel construction method of the present invention will be described with reference to FIGS. In the tunnel construction method of this embodiment, when constructing a tunnel 1 having a large cross section with respect to a spring ground, first, a pilot tunnel 2 having a small diameter is first excavated at the center of the position where the tunnel 1 is to be constructed, The pilot tunnel 2 is covered with a segment 3. Then, the ground outside the planned excavation section of the tunnel 1 is stopped by the work from the inside of the pilot tunnel 2, and then the pilot tunnel 2 is disassembled and removed by the full-section tunnel excavator 4. The main tunnel 1 is constructed by excavating the surroundings in the form of reaming.

  In that case, as shown in FIG. 1, a portal-shaped transport cart 5 is installed in the pilot tunnel 2 so as to be able to travel, so that materials can be fed from the front entrance of the pilot tunnel 2 to the full-section tunnel excavator 4. Transport. In addition, the segment transport cart 6 can travel inside the transport cart 5, and materials such as the segment 3 disassembled from the pilot tunnel 2 are transported forward.

  In this embodiment, a full-section tunnel excavator 4 for excavating the main tunnel 1 is a tunnel boring machine having a structure in which a nose gripper 7 is pressed against the inner surface of the pilot tunnel 2 and a reaction force is taken from there. (TBM), while the segment 3 in the pilot tunnel 2 is disassembled by the erector 15 provided in the foremost part, the circumference of the pilot tunnel 2 is excavated in an annular shape so as to expand the diameter of the pilot tunnel 2 by the annular cutter 8 The concrete is sprayed immediately on the inner surface of the tunnel after excavation by the lock bolt driving machine 9 and the concrete spraying machine 10 mounted thereon and the lock bolt is driven to form a primary lining. is there.

  Moreover, in the tunnel construction method of this embodiment, excavation soil is conveyed by the stretch belt conveyor 11. That is, as shown in FIG. 2, a continuous loader 12, a quantitative feeder 13, and an excavating soil loading carriage 14 are arranged in this order behind the full-section tunnel excavator 4, and these are used for the excavation of the full-section tunnel excavator 4. The excavated soil is transported while following and synchronizing and moving forward. The continuous loader 12 feeds excavation gap discharged from the full-section tunnel excavator 4 to the quantitative feeder 13, and the quantitative feeder 13 inputs the excavated soil into the excavated soil input cart 14 by a certain amount.

  The excavated soil loading carriage 14 is equipped with a pulley at the tip of the stretching belt conveyor 11, and the loaded excavating soil is continuously conveyed to the wellhead as it is by the stretching belt conveyor 11. As shown in FIG. 3, the stretch belt conveyor 11 is supported by a gantry 16 or a bracket 17 and is installed on one side of the tunnel 1, and a belt storage (see FIG. (Not shown), the extra belt is naturally pulled out so that the stretch belt conveyor 11 is naturally stretched forward.

  On the rear side, lining is performed by the lining device group 20, but in this embodiment, the lining by the segment and the lining by the cast-in-place lining wall are performed in combination, and as shown in FIG. The lining for the part is performed by the invert segment 21, and the arching for the arch part is formed on the site by forming the arch concrete 22 so as to be continuous with the invert segment 21, thereby forming the lining wall.

In this embodiment, the erector 23, the sheet pasting cart 24, the reinforcing cart 25, and the movable formwork device 26 are adopted as the lining device group 20, and the invert segment 23 is constructed by the elector 23, and the construction has been completed. The lining device group 20 (including the erector 23) is arranged in that order from the face side on the invert segment 23 , and the entire cross section is the same as the continuous loader 12, the quantitative feeder 13, and the excavated soil throwing carriage 14. The lining is performed while the tunnel excavator 4 is moved forward in synchronization with the excavation of the tunnel excavator 4.

  The erector 23 is configured to hold the invert segment 21 by the arm 23a and arrange it in the invert portion. Further, the sheet pasting carriage 24 is for pasting a sheet material to the excavation wall surface of the arch part, the reinforcing bar carriage 25 is for placing a reinforcing bar on the pasted sheet, and the movable formwork device 26 is A formwork is arranged opposite to the arch (so-called centle), and the reinforced concrete arch concrete 22 as a lining wall is efficiently formed by the sheet pasting carriage 24, the reinforcing carriage 25, and the movable formwork device 26. And it can be constructed continuously.

  The invert segment 21 has already been installed by the erector 23 at the arrangement position of the lining device group 20, but a roadbed 27 is immediately formed on the invert segment 21 at the time of installation, and the roadbed 27 is placed on the roadbed 27. A lining device group 20 is arranged. The roadbed 27 may be provided as a permanent installation, or may be provided as a temporary installation. Although the roadbed material and its construction method may be appropriate, for example, if the roadbed 27 is formed by installing a steel mount or PCa member on the invert segment 21 using the erector 23, workability is good. Of course, it is also possible to form the roadbed 27 by placing concrete on the invert segment 21 or by rolling out the excavated soil as a roadbed material onto the invert segment. In any case, if necessary, an appropriate device for roadbed construction may be provided in parallel with the erector 23 or disposed between the erector 23 and the sheet pasting device 24.

  According to the tunnel construction method of the present embodiment, only the invert portion is covered with the invert segment 21, and the arch portion is covered with the arch portion by forming the arch concrete 22 as the lining wall by placing the concrete in place. As a result, not only can the inverted part be lined up at an early stage, but it can also be used as a work roadbed to start the arched linen at an early stage for efficient lining work. The construction efficiency can be greatly improved, and the uncovered section can be shortened. Of course, since the invert portion is only about 1/3 of the entire circumference of the tunnel, the cost increase can be sufficiently suppressed as compared with the case where the segments are installed over the entire circumference as in the shield method. Therefore, the tunnel construction method of the present embodiment has both the advantages of excellent workability by segment lining and the economic efficiency of lining by cast-in-place concrete, and is particularly applicable to construction of large sections and long tunnels. It is preferable.

  Further, as the lining device group 20, a sheet pasting cart 24, a reinforcing cart 25, and a movable formwork device 26, which are construction means for conventional arch concrete 22, except for the erector 23 for installing the invert segment 21, are provided. It can be used as it is, and its construction can be done efficiently as usual.

  In addition, after the invert segment 21 is installed, a temporary or main roadbed 27 is installed on the upper portion thereof, and the lining device group 20 is arranged on the roadbed 27 to advance, so that the roadbed 27 can be installed early. It is possible to secure a stable work bed for lining work at an early stage, which is more efficient.

  In addition, the excavated soil can be efficiently conveyed by the stretching belt conveyor 11, and the excavated soil can be transferred to the excavated soil input carriage 14 by a continuous loader 12 and a quantitative feeder 13. Since they are put in, the belt conveyor 11 can be naturally stretched without any hassle by simply moving them forward following the excavation without requiring a special reordering operation. Of course, since it is not necessary to consider the direct connection between the full-section tunnel excavator 4 and the stretch belt conveyor 11, a special configuration is added to the full-section tunnel excavator 4 in order to employ the stretch belt conveyor 11. This is not necessary, and the present invention can be applied to the reaming tunnel boring machine as in this embodiment without any trouble.

  Furthermore, prior to excavation of the main tunnel 1, the pilot tunnel 2 is pre-excavated and the water stop is improved in advance around the pilot tunnel 2. Accordingly, the tunnel excavator 4 having a relatively simple structure such as an open-type tunnel boring machine can be adopted as the full-section tunnel excavator 4.

  Although one embodiment of the present invention has been described above, the above embodiment is merely a preferred example, and the present invention is not limited to the above embodiment, and details of processes, configurations of devices used, and the like are described. Needless to say, appropriate design changes may be made in accordance with the size and form of the tunnel to be excavated, the ground conditions, and other conditions.

The tunnel construction method which is embodiment of this invention is shown, and it is a figure which shows the process in the forefront part. It is a figure which shows the process in the back as well. FIG. 3 is a cross-sectional view of each part in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tunnel 2 Pilot tunnel 3 Segment 4 Full-section tunnel excavator 5 Conveyor cart 6 Segment transport cart 7 Nose gripper 8 Cutter 9 Rock bolt placing machine 10 Concrete sprayer 11 Stretch belt conveyor 12 Continuous loader 13 Fixed feeder 14 Excavation soil input Carriage 15 Elector 16 Base 17 Bracket 20 Covering device group 21 Invert segment 22 Arch concrete (lining wall)
23 Electa 23a Arm 24 Sheet pasting cart 25 Reinforcement cart 26 Mobile formwork device 27 Roadbed

Claims (4)

In the tunnel construction method of lining the excavation wall surface by advancing the full-scale tunnel excavator while moving the lining device group following the excavation behind it,
The excavating soil loading cart equipped with the tail pulley at the tip of the stretching belt conveyor is placed behind the full-section tunnel excavator, the excavating soil is thrown into the excavating soil loading cart and continuously conveyed to the wellhead by the stretching belt conveyor By following the excavation, the excavating soil throwing carriage is moved forward to stretch the stretching belt conveyor.
The invert segment is installed in the invert portion by arranging the lining device group behind the excavated soil throwing carriage and moving the lining device group along with the excavating dirt throwing carriage to follow the excavation. with, an arch of concrete as lining wall with respect to the arch portion and Da設formed continuously to invert the segment at its rear,
As the lining device group, an erector that installs an invert segment in the invert part, a sheet affixing carriage that affixes a sheet material on the excavation wall surface of the arch part, a reinforcing bar that arranges reinforcing bars on the affixed sheet, and an arch Part formwork employs a movable mold device disposed opposite to, while applying a invert segments behind the excavating soil turned carriage by said erector, its them lining unit group on construction already invert segment A tunnel construction method characterized by arranging them in order and moving them forward in synchronization. In the tunnel construction method of Claim 1 ,
A tunnel construction method comprising constructing a roadbed on an invert segment and arranging a group of lining devices on the roadbed to advance. In the tunnel construction method according to claim 1 or 2 ,
A continuous loader and fixed quantity feeder of excavated soil are arranged between the full section tunnel excavator and the excavated soil loading cart, and the excavated soil excavated by the full section tunnel excavator is transferred by the continuous loader and the fixed feeder. A tunnel construction method characterized in that a fixed amount is continuously fed into the excavated soil loading cart, and the continuous loader and the quantitative feeder are moved forward along with the excavating soil loading cart. In the tunnel construction method according to claim 1, 2, or 3 ,
Prior to excavation with a full-section tunnel excavator, a pilot tunnel with a small diameter was excavated in the center of the tunnel,
By working from the inside of the pilot tunnel, the water stop improvement to the ground outside the excavation cross section to be excavated by the full section tunnel excavator,
Thereafter, the tunnel construction method is characterized in that a pilot tunnel is excavated and the ground around the pilot tunnel is excavated in an annular shape to expand the diameter of the pilot tunnel.

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