JP2002106289A - Method and device for constructing branch gallery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cavity stability and reduce the amount of boring at a tunnel entrance among other purposes by boring a disposal gallery and the like for stratum disposal of high-level radioactive wastes and the like at right angles to a main gallery. SOLUTION: A tunnel boring machine(TBM) 11 and trailing trucks 12 have such a length as permits them to turn horizontally in a main gallery 4. They are loaded on transfer trucks 13 and 14 with rotary platforms 15 and 16 and moved on in the main gallery. In a boring position for a disposal gallery 3, the TBM 11 is turned over ninety degrees and started, and the trailing trucks 12 are turned likewise following the TBM, so that the disposal gallery 3 is bored at right angles to the main gallery 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for constructing a branch tunnel such as a disposal tunnel for geological disposal of high-level radioactive waste and the like.

[0002]

2. Description of the Related Art For example, high-level radioactive waste is obtained by dissolving unnecessary fission products remaining after separating unreacted uranium and nascent plutonium from spent nuclear fuel in nitric acid. Because it becomes difficult to handle, it is melted together with the glass raw material at high temperature and poured into a stainless steel canister to stabilize it as a vitrified body, and this vitrified body is stored in a storage facility on the ground to reduce radioactivity. After reducing the strength and heat generation, it is sealed and housed in a thick steel plate hermetic container called an overpack, and the overpack is filled with cushioning material in a bedrock several hundred to several hundred meters deep underground. It is planned to go through geological disposal. In the following, an overpack containing a vitrified body is referred to as a waste body.

FIG. 8 shows an outline of an example of a geological disposal system. An access tunnel 2 (a vertical shaft 2a, an inclined shaft 2b, a spiral tunnel 2) connecting an aboveground facility 1 and an underground facility is shown.
c) and a number of disposal tunnels 3 for embedding waste A
And a main tunnel 4 surrounding the disposal tunnel, and a connecting tunnel 5 connecting the main tunnels. The disposal panel 6 is one section composed of the disposal tunnel 3 and the main tunnel 4 surrounding the disposal tunnel 3. By dividing the area where the waste is disposed into several independent panels, the geological and environmental conditions of the disposal site are determined. There is an advantage in that a flexible layout can be performed according to the conditions, etc., and main operations such as construction, operation, and closing can be performed independently and in parallel on each panel.

[0004] In the construction stage, the above-ground facilities and underground facilities are constructed. In the operation stage, the main tasks include receiving the vitrified material, filling in the overpack, manufacturing the buffer material, transporting and setting the waste and the buffer material, and backfilling the disposal tunnel and the main tunnel. During the closure phase, the main work involved was backfilling the access and access tunnels, dismantling and breaking ground facilities.
Removal takes place.

[0005] In such a geological disposal system, there are basically four layouts for embedding and disposing of waste bodies: a disposal pit horizontal system, a disposal shaft vertical system, a disposal hole horizontal system, and a disposal hole vertical system. It can be classified into methods. Of these, a typical disposal tunnel horizontal placement method will be described below.

As shown in FIG. 9, in the construction stage, after excavating and forming the main tunnel 4 and the like, a tunnel excavator (hereinafter, referred to as a tunnel excavator) is used.
For example, the disposal tunnel 3 is excavated by excavating from one main tunnel 4 to the other main tunnel 4.

[0007] In the operation stage, the waste and the buffer material carried from the above-ground facility to the underground facility are transshipped to a stationary transporting vehicle equipped with stationary equipment, transported to the disposal tunnel 3, and separated from the transporting vehicle. The equipment is moved inside the disposal tunnel, and at the stationary position, using stationary equipment (waste body stationary equipment + buffer material block handling equipment, etc.)
The buffer material (bentonite) block divided into blocks is piled up at the lower part of the disposal tunnel 3, and after the waste body A is placed thereon, the buffer material block is covered so as to cover the front part, the upper part and the rear part of the waste body. A method has been considered in which the waste A covered with the buffer material is fixedly buried at predetermined intervals in the disposal tunnel by stacking and sequentially repeating this.

[0008] After the disposal tunnel is excavated and formed by TBM or the like, a storage tube continuous in the longitudinal direction of the disposal tunnel and a buffer material for filling a gap between the storage tube and the inner wall surface of the disposal tunnel. (Bentonite, etc.) and [Construction phase]. When the construction phase is completed, the operation phase shifts to the operation phase, where the waste is loaded into the storage tube and placed in the fixed position. It is also considered that a waste block and an intermediate block are alternately placed in a storage tube (operation stage) (Japanese Patent Application No. 11-354571).

[0009]

In the disposal site for high-level radioactive waste as described above, a large number of disposal tunnels are constructed. Therefore, the TBM is effective for excavation of the disposal tunnel. As shown in FIG. 10 (a), the main mine 4 has a long captain and the equipment for placing wastes and cushioning materials (operation robots) used in the operation stage is long. In addition to disposing the disposal tunnel 3 at an angle, it is necessary to form an arc portion 50 at a connection portion of the tunnel so that the TBM and stationary equipment can enter and exit smoothly. Therefore, there were problems such as a decrease in stability of the cavity at the entrance of the tunnel and an increase in the amount of excavation.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to form a branch tunnel, such as a disposal tunnel for geological disposal of high-level radioactive wastes, at right angles to a main tunnel. An object of the present invention is to provide a method and an apparatus for constructing a branch tunnel, which can be formed by excavation and can improve the stability of a cavity at a tunnel entrance and reduce the amount of excavation.

[0011]

A first aspect of the present invention is a method for constructing a branch tunnel by excavating and forming a branch tunnel from a main tunnel provided in the ground, wherein a tunnel excavator can be horizontally rotated in the main tunnel. The tunnel excavator is mounted on a transport trolley so that the longitudinal direction of the tunnel excavator is along the longitudinal direction of the main tunnel, and the tunnel excavator is horizontally rotated at the excavation position of the branch tunnel. This is a construction method of a branch tunnel characterized by starting a machine.

According to a second aspect of the present invention, there is provided the construction method according to the first aspect, wherein the trailing bogie having a length rotatable horizontally in the main tunnel is transported such that its longitudinal direction is along the longitudinal direction of the main tunnel. Moving in the main tunnel together with the tunnel excavator, and after the tunnel excavator starts moving, the subsequent bogie is horizontally rotated to follow the excavation of the tunnel excavator and moved in the branch tunnel. This is the construction method of the tunnel.

According to a third aspect of the present invention, there is provided a branch tunnel construction apparatus for excavating and forming a branch tunnel from a main tunnel provided in the ground, comprising: a tunnel excavator having a length rotatable horizontally in the main tunnel; A construction apparatus for a branch tunnel, characterized in that it has a rotary mounting table on which a tunnel excavator can be mounted and can be rotated horizontally, and a transport vehicle capable of traveling in a main tunnel.

According to a fourth aspect of the present invention, in the construction apparatus according to the third aspect, the trailing bogie having a length rotatable horizontally in the main tunnel and a rotary mounting table capable of horizontally rotating the subsequent bogie are mounted. This is a construction device for a branch tunnel, which is equipped with a transport trolley mounted and capable of traveling in a main tunnel.

According to a fifth aspect of the present invention, in the construction apparatus according to the third or fourth aspect, the tunnel excavator includes a short front body portion having a cutter head on a front surface and a gripping device on a side surface; An apparatus for constructing a branch tunnel, comprising a short rear trunk having a gripping device, and a propulsion device connecting the front trunk and the rear trunk.

In the first to fourth aspects of the present invention, it is preferable that the carriage is run on a rail laid on the bottom of the main tunnel. In the second and fourth aspects, it is preferable that the trailing bogie has a smaller outer diameter than that of the tunnel excavator, and the outer peripheral surface thereof is provided with wheels or the like that roll in contact with the ground surface.

According to a fifth aspect of the present invention, the gripping device for the front body includes:
It is preferable to use a hydraulic bag attached to the outer peripheral surface of the front body, and the gripping device for the rear body to be a gripper in which a pair of arc-shaped members built in the rear body expand and contract. Further, the propulsion device is constituted by a plurality of thrust jacks, and also serves as a structural material.

The branch tunnel is, for example, a disposal tunnel for wastes. Conventionally, in order to start a tunnel excavator having a long length from a main tunnel, an operation robot as stationary equipment for wastes is carried into the branch tunnel. Therefore, it was necessary to incline the branch tunnel with respect to the main tunnel, and to provide an arc portion at a connection portion between the main tunnel and the branch tunnel (FIG. 10).
(See (a)) In the present invention, the length of the tunnel excavator is shortened so that the tunnel can be rotated horizontally in the main tunnel, so that the branch tunnel can be constructed at right angles to the main tunnel (FIG. 10 (b)). )), It is possible to improve the cavity stability and reduce the amount of excavation. In addition, since it is constituted by a group of straight branch tunnels, excellent remote control of operation machines and the like in the branch tunnel becomes possible only by installing an antenna in the main tunnel.

By using a trailing bogie having a length that can be rotated horizontally in the branch tunnel, and moving the excavated branch tunnel following the tunnel excavator, the following bogie requires necessary equipment for the tunnel excavator. Materials can be shared and loaded, and a conveyor for excavating waste can also be installed. Furthermore, by providing a plurality of wheels on the outer peripheral surface of the succeeding bogie at intervals in the circumferential direction, it is possible to stably travel on the excavated branch tunnel without track.

Since the tunnel excavator and the trailing bogie are moved on the transport bogie with the rotary mounting table in the main tunnel, excavation can be started smoothly even in a main tunnel having a relatively small diameter.・ Transfer to the next process can be performed smoothly and continuous construction is possible. Also,
Several tunnel excavators can be operated simultaneously. In addition, moving systems (transportation vehicles) in the main tunnel
A shear conveyance system (belt conveyor) and the like can be shared.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. This embodiment is an example in which the present invention is applied to a high-level radioactive waste underground disposal facility (see FIG. 7). 1 and 2 show an initial stage of excavation in an example of the construction method and construction apparatus of the present invention. 3 and 4 show the end of the excavation. FIG. 5 shows the construction state of the whole (disposal panel) of the present invention. 6 and 7 show an example of a tunnel excavator (hereinafter, referred to as TBM) used in the present invention.

As shown in FIGS. 1 and 2, in the construction stage of the geological disposal system, a main tunnel 4 is formed in a bedrock having a depth of, for example, several hundred meters underground. In use, a disposal tunnel 3 which is a branch tunnel is excavated at right angles to the main tunnel 4.

The construction apparatus 10 includes a TBM 11 having a length rotatable in the main tunnel 4 and a plurality of TBMs 11 (four in the illustrated example).
, A carriage 13 for the TBM, and a carriage 14 for the subsequent carriage. The carriages 13, 14 are provided with rotary mounting tables 15, 16, respectively, so as to be horizontally rotatable. The TBM 11 is the rotary mounting table 1
The trailing carriage 12 is placed on 6.

The TBM 11 has a substantially cylindrical shape with a diameter (excavation diameter) of D and a length of L, and is designed so that the length of the TBM 11 is significantly shorter than that of a conventional TBM as will be described in detail later. I have.

The trailing bogie 12 has a cylindrical shape, a rectangular cylindrical shape or the like having an outer diameter slightly smaller than the machine length D of the TBM 11, and a plurality of wheels 17 are provided on its outer peripheral surface at equal intervals in the circumferential direction (four in the illustrated example). ) Is provided. The diameter of the outermost rolling surface of the wheel 17 is set to be substantially equal to the excavation diameter D, so that the wheel 17 can run stably without track while holding the inner wall surface of the disposal tunnel 3.

The trailing truck 12 has a TBM 11
Equipment and materials necessary for tunnel excavation, such as battery and hydraulic equipment and sprayed concrete and its equipment, are mounted and shared, and within each subsequent bogie 12, a conveyor for carrying out excavated waste is provided. Have been.

The carriages 13 and 14 are devices that travel inside the main tunnel 4 and the like and automatically transport the TBM 11 and the succeeding carriage 12 to a predetermined disposal tunnel excavation position. It runs on a pair of rails 18 laid in parallel. The transport carts 13 and 14 are connected to each other by a connector, or the TBM 11 and the subsequent truck 12 are connected to each other by a detachable connector, and run as trains. In addition, at least the first one of the transport vehicles 13 and 14 is a power vehicle.

The rotary mounting tables 15 and 16 are semi-circular receiving bases corresponding to the outer diameters of the TBM 11 and the succeeding bogie 12.
It is a turntable that rotates horizontally with a motor and gears. The length of the rotary mounting tables 15 and 16 is TBM11 ·
It should be shorter than the length of the trailing carriage 12.

As shown in FIG. 6, the TBM 11 has a front body portion 20 having a cutter head 21 on the front surface and a gripping device 22 on the side surface, a rear body portion 23 having a gripping device 24 on the side surface, and
A propulsion device 25 connects these front and rear trunks. The basic structure is the same as that of a normal TBM. The gripping device 24 of the rear trunk 23 is pressed against the ground surface to take a reaction force, and the front trunk 20 is propelled by the propulsion device 25. The trunk 20 is fixed to the ground surface by the gripping device 22 and the rear trunk 23 is attracted by the propulsion device 25, and by repeating this, the tunnel is excavated while traveling on its own. In the case of hard rock, the ground surface is lined with sprayed concrete or segments in the case of soft rock.

In the TBM having such a structure, the length of the front body portion 20 and the length of the rear body portion 23 are designed to be extremely short. That is, the gripping device 22 of the front body 20 can be attached to the outer surface of the front body 20 such as a hydraulic bag type, and the length of the front body 20 is greatly reduced. A large number of hydraulic bags 22 are provided in the circumferential direction. The cutter head 21 is rotatably provided on the front body 20 via a main bearing 26, and is rotationally driven by a drive motor 27 provided on the back surface of the front body 20.

The gripping device 24 for the rear body 23 includes a pair of left and right arc-shaped gripper shoes 24 inside the ring-shaped rear body 23.
a, and a pair of gripper jacks 24b disposed between the gripper shoes 24a.
The length of the rear trunk portion 23 is greatly reduced by employing a structure in which a is moved in a scale.

Further, the propulsion device 25 is composed of a plurality of thrust jacks, which are arranged so as to be inclined with respect to the excavation direction, and are arranged in a truss-like shape in a side view so as to also serve as a structural material. I have. By using the propulsion device 25 as a structural material and disposing it at an angle, the front body 2
The distance between 0 and the rear trunk 23 can be reduced. Also,
As shown in FIG. 7, the propulsion device 25 arranged in a truss shape enables a sharp curve excavation of, for example, R10m. Note that by controlling the gripping devices 22 and 24, the TB
By causing the cutter head 21 to revolve by displacing M itself, the tunnel can be widened to some extent and used for plug installation and the like.

In the case of the TBM 11 configured as described above, for example, when the excavation diameter D is slightly more than 2 m, the machine length L can be slightly more than 3 m, and even if the main tunnel has a small diameter of about 5 m, the TBM 11 can be used. Can be turned horizontally in the main tunnel with ample room, making it possible to construct the disposal tunnel at right angles.

As shown in FIG. 6, inside the TBM 11, a hopper chute 28 and a hopper chute 28 for discharging excavated shears are provided.
A jet pump 29, a discharge pipe 30, and the like are provided.
The disposal tunnel is excavated as follows using the construction apparatus 10 configured as described above (see FIGS. 1 to 5).

(1) As shown in FIGS. 1 and 2, the TBM 11
・ Place the trailing trucks 12 on the transport trucks 13 and 14, respectively.
The main tunnel 4 is moved. (2) When the leading TBM 11 reaches the disposal tunnel excavation position, the rotary mounting table 15 of the transport vehicle 13 is rotated by 90 °. (3) At the entrance of the disposal tunnel excavation position, a TBM starting reaction force receiving pit 31 is previously installed, and the TBM 11 is inserted into the reaction force receiving pit 31. This insertion operation can be performed using a pushing device or the like provided on the rotary mounting table 15 or a transfer device or the like provided in the main tunnel 4.

(4) The initial excavation of the TBM 11 is started. The trailing bogie 12 is also rotated by 90 ° in the same manner as described above, and
Follow 11 The succeeding bogie 12 is connected by a connector or the like, and is moved by being pulled by the TBM 11. The excavated waste is conveyed to the main tunnel 4 by a conveyor arranged in each subsequent bogie 12. The main shaft 4 to the shaft are transported by a belt conveyor 32 installed in advance.

(5) As shown in FIGS. 3 and 4, the TBM 11
Digs up to the destination. (6) The transport trolleys 13 and 1 are located in the main tunnel 4 where the excavation is completed.
4 is on standby, and the TBM 11 for which excavation has been completed is transferred onto the carrier 13. The succeeding carriages 12 are also sequentially transferred onto the transport carriages 14. (7) The TBM 11 and the succeeding bogie 12 move in the main tunnel 4 and perform maintenance of the TBM 11, and then are transported to the excavation position of the next disposal tunnel. As described above, since the TBM 11 and the subsequent bogie 12 are mounted on the transport bogies 13 and 14 with the rotary mounting table and moved in the main tunnel, excavation can be started smoothly even in a relatively small-diameter main tunnel, In addition, movement, excavation, and movement to the next process can be smoothly performed, and continuous construction can be performed.

Further, as shown in FIG. 5, several TBMs can be operated simultaneously. Further, in one underground disposal facility, a plurality of TBMs or the like can be operated at the same time by sharing a moving system (transportation trolley) such as a TBM and a dispensing facility (belt conveyor).

Further, as shown in FIG. 10 (b), the disposal tunnel 3 can be constructed at right angles to the main tunnel 4, so that the inclined arrangement and the arc portion as shown in FIG. 10 (a) can be eliminated. It is possible to improve the stability of the cavity and reduce the amount of excavation. In addition, in a conventional disposal tunnel having an arc portion in an inclined arrangement, an antenna for remote control is also required in the disposal tunnel, but since the present invention is configured with a group of straight tunnels,
Just by installing an antenna in the main tunnel 4, T
Good remote operation such as BM can be performed.

In the operation stage, Japanese Patent Application No. Hei 11-354
By using the technology of No. 571, it is possible to place a waste body and a buffer material in a disposal tunnel constructed at right angles. Also, the horizontal disposal tunnel of an underground disposal facility for high-level radioactive waste has been described above, but it goes without saying that the present invention is also applied to other waste disposal tunnels or branch tunnels for other uses.

[0041]

Since the present invention has the above-described configuration, the following effects can be obtained.

(1) Since the length of the tunnel excavator is shortened and the tunnel excavator can be rotated horizontally in the main tunnel, the tunnel excavator can be turned at a right angle, and the branch tunnel is constructed at a right angle to the main tunnel. It is possible to improve the stability of the cavity and reduce the amount of excavation. (2) Because the branch tunnel can be composed of a group of straight branch tunnels,
Only by installing the antenna in the main tunnel, good remote operation of the operating machines and the like in the branch tunnel becomes possible.

(3) By using a trailing bogie having a length capable of horizontal rotation in the branch tunnel and moving the excavated branch tunnel following the tunnel excavator, the trailing bogie is required for the tunnel boring machine. Equipment and materials can be shared and loaded, and a conveyor for excavating waste can also be installed, making it possible to use a tunnel excavator with a short length to make a right angle construction of a branch tunnel. (4) By arranging a plurality of wheels on the outer peripheral surface of the succeeding bogie at intervals in the circumferential direction, it is possible to run stably in the excavated branch tunnel without track, and to perform the right angle construction of the branch tunnel safely. .

(5) A tunnel excavator or a trailing bogie is mounted on a transport bogie equipped with a rotary mounting table and moved in the main tunnel, so that excavation can be started smoothly even in a main tunnel having a relatively small diameter. Movement, excavation and movement to the next process can be performed smoothly, enabling continuous construction,
The right angle construction of the branch tunnel can be performed quickly. (6) Several tunnel excavators can be operated at the same time, shortening the construction period and reducing costs. (7) The common transport system (transportation trolley) and shear transport system (belt conveyor) in the main tunnel can be shared.
Cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an example of a method and an apparatus for constructing a branch tunnel according to the present invention, and is a perspective view showing an initial stage of excavation.

FIG. 2 is a plan view of FIG.

FIG. 3 is an example of a method and an apparatus for constructing a branch tunnel according to the present invention, and is a perspective view showing a state at the end of excavation.

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a perspective view showing an overall construction state of the present invention.

6 shows an example of a tunnel excavator (TBM) used in the present invention, wherein (a) is a longitudinal sectional view, (b) is a transverse sectional view of a front trunk portion, and (c) is a front view. FIG. 3D is a cross-sectional view of the rear trunk.

FIG. 7 is a plan view showing a curved construction state of the TBM of FIG. 6;

FIG. 8: Geological disposal system for high-level radioactive waste 1
It is a perspective view showing an example.

FIG. 9 is a perspective view showing a method of placing a waste body in a disposal tunnel in a geological disposal system.

FIG. 10 is a schematic plan view showing the shape of a disposal tunnel in a geological disposal system for waste, wherein FIG.
(b) shows the case of the present invention.

[Explanation of symbols]

 A: Waste 1: Ground equipment 2: Access tunnel 2a: Vertical shaft 2b: Inclined tunnel 2c: Spiral tunnel 3 ... Disposal tunnel (branch tunnel) 4 ... Main tunnel 5 ... Contact tunnel 6 ... Disposal panel 10 ……………………………………………………………………………………………………………… Construction equipment 11 …… Tunnel excavator (TBM) 12 …… Subsequent trolley 13 …… Transport trolley 14 …… Transport trolley 16 ... ... front body 21 ... cutter head 22 ... gripping device (hydraulic bag) 23 ... rear body 24 ... gripping device (gripper) 24a ... gripper shoe 24b ... gripper jack 25 ... ... propulsion device 26 ... ... main bearing 27: Drive motor 28: Hopper chute 29: Jet pump 30: Discharge pipe 31: TBM receiving reaction force receiving shaft 32 when starting TBM 32: Belt conveyor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuo Okitsu 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. F-term (reference) 2D054 EA07 EA09

Claims (5)

[Claims] 1. A method for constructing a branch tunnel in which a branch tunnel is excavated from a main tunnel provided in the ground, the tunnel excavator having a length capable of being horizontally rotated in the main tunnel, and the tunnel excavator having a longitudinal direction. Is mounted on a transport trolley along the longitudinal direction of the main tunnel, moves inside the main tunnel, and rotates the tunnel excavator horizontally at the excavation position of the branch tunnel to start the tunnel excavator. Construction method. 2. The tunnel excavator according to claim 1, wherein a trailing bogie having a length rotatable horizontally in the main tunnel is mounted on a transport bogie such that its longitudinal direction is along the longitudinal direction of the main tunnel. A method for constructing a branch tunnel, comprising: moving the tunnel boring machine horizontally after the tunnel boring machine has started, moving the trailing bogie horizontally to follow the excavation of the tunnel boring machine. 3. A branch tunnel construction apparatus for excavating and forming a branch tunnel from a main tunnel provided in the ground, comprising: a tunnel excavator having a length rotatable horizontally in the main tunnel; An apparatus for constructing a branch tunnel, comprising: a carriage mounted on a rotary mounting table capable of horizontal rotation and capable of traveling in a main tunnel. 4. The construction apparatus according to claim 3, wherein a trailing bogie having a length rotatable horizontally in the main tunnel and a rotary mounting table rotatable on which the trailing bogie is mounted are mounted on the main tunnel. An apparatus for constructing a branch tunnel, comprising a transportable carriage. 5. The construction apparatus according to claim 3, wherein the tunnel excavator has a short front body portion having a cutter head on a front surface and a gripping device on a side surface, and a short length having a gripping device on a side surface. A branch tunnel construction device comprising a rear trunk and a propulsion device connecting the front trunk and the rear trunk.