JP2008285846A - Gallery closing method and gallery closing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gallery closing method and a gallery closing device capable of suitably refilling a gallery by holding a compacted backfill material at a predetermined degree of compaction. <P>SOLUTION: A bearing plate 14 comprises a window part 14b and a through hole 14e through which a bar-like member 22 supplying the backfill material 3 on one end 22a and supported on the rear space 12 side is extended. A backfill material holding plate 24 is installed by supporting on the bar-like member 22 on the rear surface 14c side of the bearing plate 14 through the window part 14b. Next, a backfill material holding plate 24 pressed by the rear surface 14c of the bearing plate 14 together with the backfill material 3 is moved backward while being guided by the bar-like member 22 by advancing the bearing plate 14 backward. When the backfill material 3 is compacted by the bearing plate 14, the backfill material holding plate 24 is secured to the bar-like member 22, and the compacted backfill material 3 is held by the backfill material holding plate 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mine closing method and a mine closing device for refilling and closing a mine of a waste burying disposal facility for burying waste such as radioactive waste by using a backfill material.

  For example, it has been studied to bury high-level radioactive waste in a deep underground area exceeding 300 m underground. At this time, the radioactive waste is solidified by mixing with glass, for example, and is disposed in a state in which the solidified glass is sealed with an overpack made of carbon steel or the like to form a waste. Then, as shown in FIGS. 6 and 7, the waste body is connected to a main tunnel 1 that is connected in a substantially ring shape within a relatively stable natural ground G of hard rock and sedimentary soft rock (soft rock) in the deep underground, A waste burial disposal facility A consisting of a disposal mine (tunnel) and a disposal hole (hereinafter referred to as a disposal mine 2) formed so as to be connected to the main mine shaft 1 is constructed. It is disposed (see, for example, Patent Document 1). For example, when the disposal mine 2 for disposing the waste is formed in a hard rock ground G, after excavating the ground G, a lining of about 5 cm thick and an invert of about 15 cm thick are provided. When it is formed by shotcrete or concrete and is formed in the soft rock ground G, these linings and inverts are thickly formed with a thickness of 50 cm to stabilize the ground rock G, and the disposal tunnel 2 is prevented from falling into and out of the ground.

  Moreover, if the disposal tunnel 2 where the waste has been disposed is left as it is, there is a risk that an expansion of the natural ground G around the disposal tunnel 2 and an excellent waterway in the groundwater may be formed. There is a risk of reducing the barrier performance. For this reason, it is considered that the disposal tunnel 2 is backfilled with a low water permeability material (backfill material 3) equal to or greater than the natural ground G. And this type of backfill material 3 is made of bentonite or bentonite mixed material (bentonite-based clay material), which is excellent in swelling property and radioactive material adsorption property, and is a low water material. The groundwater infiltrated into 2 is in contact with it and swells and presses the natural ground G to prevent further infiltration of groundwater, or the permeation coefficient of the backfill material 3 decreases with swelling to prevent infiltration of groundwater. . This makes it possible to reliably dispose of radioactive waste from the outside natural environment.

  On the other hand, when groundwater comes into contact with the lining or invert (supporting work) formed of shotcrete, Ca (calcium) and high alkali components are eluted from the cement into the groundwater, and the area around the disposal tunnel 2 is highly alkaline. There is a possibility of becoming an environment. In this way, when the disposal tunnel 2 becomes a highly alkaline environment, the backfill material 3 may be deteriorated particularly by Ca ions. That is, the bentonite clay material of the backfill material 3 is frequently Na (sodium) type bentonite in terms of its excellent swellability. When this Na type bentonite comes into contact with Ca ions, the ions of Na and Ca are used. Exchange will be made and it will change into Ca type | mold bentonite which is inferior to swelling property. Thus, when bentonite changes in quality, the swelling property of the backfilling material 3 becomes poor, and there is a possibility that the shielding ability of groundwater and thus the shielding ability of radioactive substances may be lowered. For this reason, it is considered to remove the support work and prevent deterioration of the backfill material 3 due to the concrete before the waste body is transported and placed in the disposal tunnel 2 and backfilled with the backfill material 3. ing.

Further, for example, Patent Document 2 discloses a tunnel closing device (tunnel burying device) for excavating and removing a supporting work and closing (removing) backfill material into the tunnel space from which the supporting work is removed to close the tunnel. Return device) is disclosed. This tunnel closing device consists of an outer cylinder that prevents the collapse of natural ground, an intermediate cylinder that has a cutter head at the tip, and an inner cylinder that shields the inside and outside of the apparatus, and can be moved back and forth by a jack (in the axial direction of the tunnel) It is configured with a triple-cylinder front barrel that can be advanced and retracted. Further, a rear cylinder composed of a cylinder and a partition wall (pressure bearing plate) that seals the rear end portion of the cylinder is slidably fitted to the rear part of the front cylinder and can be moved back and forth by a hydraulic cylinder connected to the front cylinder ( It can be moved forward and backward in the axial direction of the tunnel). In this tunnel closing device, it is possible to move the front barrel back and forth and sequentially remove the supporting work in the tunnel axis direction by the cutter head. In parallel with the removal work of the support work by the cutter head, a backfill material such as earth and sand is put in the space on the rear side (backfill side) in the direction of the tunnel axis after the support work removal of the tunnel divided by the bulkhead of the rear trunk. The charged backfill material can be pressed and compacted by charging and moving (advancing) this partition wall to the rear side of the tunnel with a hydraulic cylinder. Then, after the backfill material is compacted in this way, the backfill material and the bulkhead that have been compacted by moving (withdrawing) the bulkhead to the front side in the mine shaft axis direction (front trunk side, excavation direction side of the support work) A new space for filling the backfill material is formed between them, and a series of operations of filling the backfill material, compacting the backfill material by moving the partition wall, and forming a new space are sequentially repeated. Then, while removing the support work, the mine shaft was backfilled and closed.
JP 2003-215297 A JP 2001-1515797 A

  However, in the tunnel closing device (tunnel backfilling device) disclosed in Patent Document 2 described above, after the backfill material is compacted, the partition wall is formed in the tunnel so as to form a new space for introducing the backfill material. When retracted forward, there is no support for the compacted backfill material, that is, the front surface of the compacted backfill material is opened, so the backfill material (the front surface of the compacted backfill material) There is a risk of collapse.

  If the front surface of the backfill material after compaction has collapsed in this way, the backfill material is introduced into the newly formed space, and the backfill material is pressed and compacted by the partition wall and collapsed. The backfill material is compacted, the backfill material is unevenly filled in the tunnel, and the tunnel cannot be backfilled with the backfill material having a predetermined degree of compaction (density). there were. In particular, if the disposal mine where radioactive waste is disposed is backfilled with such non-uniform compaction, the shielding performance of radioactive materials may be reduced, and safety and reliability may be impaired. become.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a tunnel closing method and a tunnel closing device that can hold back a compacted backfill material at a predetermined degree of compaction and suitably backfill the tunnel. .

  In order to achieve the above object, the present invention provides the following means.

  According to the mine shaft closing method of the present invention, a bearing plate provided so as to be capable of advancing and retreating in the axial direction so as to divide the mine shaft into a space on the front side in the axial direction and a space on the rear side in the shaft direction is provided on the rear side in the axial direction. In the tunnel closing method in which the backfill material supplied to the space on the rear side is advanced and pressed against the back surface of the support plate and is compacted to refill the tunnel, the support plate has the front side and the rear side. And a through-hole through which a rod-like member supported at one end side on the space side on the rear side passes, and the rod-like member on the back side of the bearing plate through the window portion. The backfilling material holding plate is installed in a supported state, and the backfilling material is supplied to the space on the rear side, and the backfilling material is pressed together with the backfilling material by the advancement of the backpressure plate. Return material holding plate The backfilling material holding plate is fixed to the rod-shaped member when the backfilling material is compacted by the pressure bearing plate and is moved to the rear side in the axial direction while being guided by the stick-shaped member, and the backfilling material is held. The backfill material compacted with a plate is held.

  In this invention, for example, a rod-like member that is embedded and supported at one end side in a previously filled back-up material is inserted through the through-hole of the bearing plate, and the back-filling material held on this rod-like member is held. The backfill material can be compacted while moving (advancing) the plate to the rear side (backfill side) in the axial direction of the mine shaft with the advancement of the bearing plate. Then, with the backfill material compacted at a predetermined degree of compaction, the backfill material holding plate pressed against the front surface of the backfill material is fixed to the rod-like member, and the backfill material holding plate is tightened. The front of the hardened backfill material can be retained. As a result, when the bearing plate is moved (retracted) forward in the axial direction of the mine shaft so as to form a new space for supplying (injecting) the backfill material (the bearing plate is moved to the excavation direction side of the support ( In the case of evacuation), the backfill material that has been compacted is held by the backfill material holding plate, so that the backfill material that has been compacted securely (the front of the backfill material) is prevented from collapsing. it can.

  Further, in the tunnel closing method of the present invention, the rod-shaped member is a screw rod having a male screw thread on the outer periphery, and the backfilling material holding plate is attached to the rod-shaped member by a nut screwed into the rod-shaped member. It is desirable to fix to.

  In this invention, while the compacted backfill material is supported by the support plate, that is, before the support plate is moved (retracted) to the front side, the nut screwed to the rod-like member is tightened and backfilled The backfilling material holding plate pressed against the backfilling material can be fixed so as to be sandwiched between the front surface of the material and the nut. As a result, the backfilling material holding plate can be reliably fixed to the rod-like member by a simple operation of tightening the nut, and collapse of the backfilled material that has been securely and simply compacted can be prevented.

  The mine closing device of the present invention is a mine closing device for supplying a backfill material into a mine shaft and compacting it to refill the mine shaft, and the inside of the mine shaft includes a space on the front side in the axial direction of the mine shaft. And a space for the back side in the axial direction for supplying the backfill material, and a support plate provided so as to be able to advance and retreat in the axial direction, the support plate being provided on the front side and the back side. It is characterized by comprising a window portion for communicating both spaces, and a through hole through which a rod-like member whose one end side is supported on the space side on the rear side passes.

  In this invention, for example, a rod-like member supported by being buried in one end side in a previously filled backfill material is inserted through the through-hole of the bearing plate, and the buried member installed through the window in the rod-like member is provided. The return material holding plate is compacted with the back material supplied to the space on the rear side by the advancement of the pressure plate, and is moved to the rear side in the axial direction of the tunnel while being guided by the rod-shaped member. As a result, the backfill material holding plate pressed against the front surface of the backfill material is fixed to the rod-shaped member in a state where the backfill material is compacted at a predetermined degree of compaction. The compacted backfill can be retained even when the bearing plate is moved (withdrawn) to form a new space for supplying (injecting) backfill material that can hold the compacted backfill material in front. Since the material is held by the backfilling material holding plate, it is possible to prevent the backfilling material (the front surface of the backfilling material) that has been securely compacted from collapsing.

  Moreover, in the tunnel closing device of the present invention, the rod-shaped member is a screw rod having a male screw thread on the outer periphery, and the through hole is the other end of the rod-shaped member disposed in the front space. It is desirable that the nut screwed from the side is formed in such a size that it can be inserted.

  In this invention, while supporting the compacted backfill material with the support plate, that is, before moving (retracting) the support plate to the front side, the nut screwed from the other end side of the rod-shaped member, It can be tightened so as to be sandwiched between the front surface of the backfilling material and the nut through the through hole, and the backfilling material holding plate can be fixed in a state where it is securely pressed against the backfilling material. As a result, the backfilling material holding plate can be reliably fixed to the rod-like member by a simple operation of tightening the nut, and collapse of the backfilled material that has been securely and simply compacted can be prevented.

  According to the tunnel closing method and the tunnel closing device of the present invention, when the bearing plate is moved (retracted) forward in the axial direction of the tunnel so as to form a new space for supplying the backfill material (the bearing plate is supported). Even when the work is moved (withdrawn) to the excavation direction side), it is possible to prevent collapse of the backfill material (the front surface of the backfill material) that has been firmly compacted, so there is no backfill material in the tunnel. Uniform filling can be prevented, and the tunnel can be backfilled with a backfilling material having a predetermined compaction degree (density). Thus, for example, when applied to backfilling (closing) a tunnel where radioactive waste has been disposed of, it is possible to dispose of radioactive waste in a stable state over a long period of time without causing a reduction in the shielding performance of the radioactive material. It becomes possible, and the tunnel can be closed while ensuring safety and reliability.

  Hereinafter, a mine closing method and a mine closing device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. In the present embodiment, for example, a disposal tunnel (tunnel) 2 of a waste embedding disposal facility A for embedding and disposing of high-level radioactive waste in a natural ground G in a deep underground area exceeding 300 m underground as shown in FIGS. 6 and 7. Is a mine closing method and a mine closing device for backfilling with a bentonite clay backfilling material 3. Here, as shown in FIGS. 1 and 2, the disposal tunnel 2 of the present embodiment is formed in a ground rock G of hard rock such as granite, and has a thickness of about 5 cm formed by sprayed concrete (concrete). A lining and an invert (supporting work 4) having a thickness of about 15 cm are provided.

  As shown in FIGS. 1 to 3, the mine closing device B of the present embodiment includes a covering member 10 having a substantially arc-shaped cross section formed along the natural ground surface (inner surface) G1 of the disposal mine shaft 2 in the circumferential direction. The protector 11 and the disposal tunnel 2 (inside) are partitioned into a space 12 on the rear side in the axis O1 direction of the disposal tunnel 2 for supplying the backfill material 3 and a space 13 on the front side in the axis O1 direction in which the protector 11 is arranged. It is connected to the substantially flat plate-shaped bearing plate 14, the protector 11 and the bearing plate 14 formed so as to expand and contract in the direction of the axis O1 of the disposal tunnel 2 and move the protector 11 and the bearing plate 14 in the direction of the axis O1 ( The propulsion mechanism 15 is moved forward and backward in the direction of the axis O 1, and the backfilling material supply device 16 and the suspension device 17 are arranged inside the protector 11 and below the covering member 10.

  The protector 11 includes a pair of support pillars 20 disposed on both sides of the bottom surface G2 (ground surface G1) of the disposal tunnel 2 in the direction orthogonal to the axis O1 and extending in the direction of the axis O1, and the ground of the disposal tunnel 2 A plurality of column members 21 formed in an inverted U shape so as to follow the side surface G3 of the surface G1 and the arch-shaped upper surface G4, and a covering member 10 provided along the upper surface G4 side of the disposal mine shaft 2 are configured. Has been.

  The plurality of column members 21 are provided so that both ends thereof are connected to the upper surfaces of the pair of column support members 20 to connect the pair of column support members 20, and have a predetermined interval in the direction of the axis O <b> 1 of the disposal tunnel 2. Opened side by side. Moreover, the support | pillar member 21 (21a) distribute | arranged to the front end side (front side) of the protector 11 is arrange | positioned at the back end side rather than the front-end | tip 20a of the support | pillar support member 20 at this time, and the back end side (rear side) of the protector 11 The support member 21 (21 b) disposed on the support member 20 is disposed near the rear end 20 c of the support member 20.

  The covering member 10 is composed of a plurality of substantially rectangular plate-like steel plates 10a, and each steel plate 10a extends in the direction of the axis O1 from the vicinity of the front end of the protector 11 to the vicinity of the rear end, and is arranged in parallel in the circumferential direction. Yes. In addition, these steel plates 10a are fixedly supported on the surfaces facing the outside of the plurality of support members 21, and are connected to the support members 21 (21a) on the front side to the support members 21 (21b) on the rear side. ing. And this covering member 10 is the backfill material supply apparatus 16 arrange | positioned inside the protector 11, ie, the downward direction of the covering member 10, when this rock piece hits the steel plate 10a, for example, when a rock piece peels off from the natural ground surface G1. And it prevents falling to the suspension device 17 and protects them.

  On the other hand, as shown in FIGS. 1, 3, and 4, the bearing plate 14 is formed with an area slightly smaller than the inner cross section of the disposal tunnel 2 and is provided orthogonal to the axis O <b> 1 of the disposal tunnel 2. Yes. The bearing plate 14 is disposed opposite to the rear end of the protector 11, one end is connected to the front surface 14 a of the bearing plate 14 facing the protector 11, and the other end is a column member 21 on the rear end side of the protector 11. (21b) and supported by a propulsion mechanism 15 interposed between the protector 11 and the bearing plate 14. Further, the bearing plate 14 is provided with a window portion 14b that opens in a rectangular shape at the center on the upper side thereof, and this window portion 14b is provided so as to be able to advance and retract in the horizontal direction along the back surface 14c of the bearing plate 14. The door member 14d is opened and closed. By providing such a window portion 14b, the space 12 on the rear side for supplying the backfill material 3 partitioned by the pressure bearing plate 14 and the space 13 on the front side in which the protector 11 is disposed can communicate with each other.

  Further, as shown in FIGS. 3 and 4, a plurality of through holes 14 e penetrating from the front surface 14 a to the back surface 14 c are provided in the pressure bearing plate 14 of the present embodiment in a distributed manner. And in each through-hole 14e, in the state which has arrange | positioned the bearing plate 14 in the predetermined position of the disposal tunnel 2, as shown in FIG. A steel bar (bar-shaped member) 22 that is supported and extended in the direction of the axis O1 of the disposal tunnel 2 is inserted so as to penetrate the bearing plate 14. Further, as shown in FIG. 5, the steel rod 22 of the present embodiment is a screw rod having a male screw 22b threaded on the outer periphery, and each through hole 14e is disposed in the space 13 on the front side. The nut 23 screwed from the other end 22c side of the steel rod 22 is formed in such a size that it can be inserted.

  The propulsion mechanism 15 is, for example, a slide jack, and as shown in FIG. 1, the support member 21 (21 b) on the rear end side of the protector 11 with the expansion / contraction direction arranged parallel to the axis O 1 of the disposal tunnel 2 ( A plurality of support members 20 are connected to a support member (21b) provided on the rear end (one end) side in the axis O1 direction of the pair of support members 20, and a plurality of the support members 20 are installed at predetermined intervals along the support member 21 (21b). Yes. The plurality of propulsion mechanisms 15 expands and contracts in the direction of the axis O1 by the synchronized driving, and changes the distance between the protector 11 and the bearing plate 14 in the direction of the axis O1 of the disposal tunnel 2, that is, the propulsion mechanism 15 By the drive, the protector 11 and the bearing plate 14 are moved closer to, away from, or relatively moved in the direction of the axis O1 of the disposal tunnel 2.

  As shown in FIG. 1, the backfilling material supply device 16 of the present embodiment is provided on a front side of the vehicle body portion 16 a including a tank for storing the backfilling material 3 and the like so as to be self-propelled. The articulated arm 16b is supported by the tip of the articulated arm 16b, and a nozzle portion 16c that ejects the backfill material 3 pumped from the tank. And this backfilling material supply apparatus 16 is arrange | positioned at the rear end side of the protector 11, and the back side provided with the articulated arm 16b is the back-pressure plate 14 side (the axial O1 direction back side of the disposal tunnel 2, backfilling). Side). At this time, the backfilling material supply device 16 is provided between the pair of column support members 20 of the protector 11 in a state where the wheels are arranged on the bottom surface G <b> 2 of the disposal tunnel 2. Thereby, the backfilling material supply device 16 is disposed below the covering member 10 of the protector 11.

  On the other hand, the suspension device 17 includes a vehicle body portion 17a configured to be self-propelled, and a beam portion 17b supported by the vehicle body portion 17a and provided to protrude forward. Further, the rear end side of the beam portion 17b is supported on the front side of the vehicle body portion 17a and extends to the front side of the vehicle body portion 17a, and a rotary cutter 17c is provided at the front end thereof. Further, the beam portion 17b is provided so as to be rotatable in the horizontal direction and the vertical direction with the rear end side supported by the vehicle body portion 17a as a rotation center, and rotates around the central axis of the rotary cutter 17c provided at the tip. In addition, the rotary cutter 17c is configured to be extendable in the central axis direction so that the rotary cutter 17c can be fed forward in the central axis direction. On the other hand, the rotary cutter 17c is formed in a truncated cone shape, and a plurality of cutting blades (not shown) projecting outward, for example, are provided on the outer surface thereof.

  And the suspension apparatus 17 comprised as mentioned above is arrange | positioned at the front end side of the protector 11, and the front side provided with the beam part 17b is the axis line O1 direction front side of the disposal tunnel 2 (the excavation direction side of the support work 4). It is arranged toward the. At this time, the suspension device 17 is installed such that the distal end side of the beam portion 17b, that is, the rotary cutter 17c is arranged forward from the distal end of the protector 11 in the direction of the axis O1. Further, the suspension device 17 is arranged below the covering member 10 of the protector 11 and supports a pair of support columns in a state where its wheels are arranged on the bottom surface G2 of the disposal mine shaft 2 in the same manner as the backfill material supply device 16. It is provided between the members 20.

  Next, a method for closing the disposal tunnel 2 using the tunnel closing device B having the above-described configuration will be described, and the operation and effect of the tunnel closing method and the tunnel closing device B of the present embodiment will be described.

  In the present embodiment, the tunnel closing device B is installed in the disposal tunnel 2 in a state where the propulsion mechanism 15 is contracted so that the distance between the protector 11 and the bearing plate 14 is minimized. At this time, the end 22a side of the through hole 14e of the bearing plate 14 precedes, for example, the backfill material 3 filled in the space 12 (backspace 12) on the rear side in the direction of the axis O1 of the disposal tunnel 2 The mine closure device B is installed by inserting the supported steel rod 22. Thereby, the steel rod 22 is arranged on the space 13 side (the protector 11 side, the excavation direction side of the support work 4) on the front side in the axis O1 direction of the disposal mine shaft 2 with the other end 22c defined by the support plate 14.

  Next, the door member 14d of the bearing plate 14 is retracted to open the window portion 14b. As shown in FIGS. 4 and 5, the operator forms a backfilling material holding plate 24 that is formed in a disc shape and includes a slit 24 a that is notched in the radial direction from the outer peripheral edge to the center through the window portion 14 b. Installed on each steel rod 22. At this time, the steel rod 22 is inserted into the slit 24a and supported by the steel rod 22, and the backfilling material holding plate 24 is installed, and one surface 24b of the backfilling material holding plate 24 faces the back surface 14c of the bearing plate 14. And are placed close to each other. Further, the nut 23 is screwed from the other end 22 c of the steel rod 22.

  Thus, at the stage where the backfilling material holding plate 24 is attached to each steel rod 22, the articulated arm 16b of the backfilling material supply device 16 is extended, and the rear side space partitioned by the bearing plate 14 from the opened window portion 14b. The nozzle portion 16 c is inserted into the space 12, and the backfilling material 3 is sprayed and supplied (supplied) into the space 12. When the back space 12 is filled with the backfill material 3 in this manner, the window portion 14b of the bearing plate 14 is closed. At this stage, the charged backfill material 3 is not filled with a predetermined degree of compaction (density).

  On the other hand, in this embodiment, while the backfilling material 3 is being charged in the backfilling material supply device 16 in this way (simultaneously), the suspension device 17 is positioned forward of the protector 11 in the direction of the axis O1 by the lifting device 17. The concrete (supporting work 4) is picked up and removed. That is, the beam portion 17 b is rotated around the rear end, and the rotary cutter 17 c is positioned near the surface of the support work 4. Next, while rotating the rotary cutter 17c around the central axis, it is brought into contact with the surface of the support 4 with a predetermined pressing force, and the suspension of the support 4 is started with the cutting blade. Further, the beam portion 17b is rotated along the inner circumference of the disposal tunnel 2, and the support work 4 is suspended and removed (excavated) over the entire circumference of the disposal tunnel 2. At this time, the support 4 in a predetermined section in the direction of the axis O1 is removed by extending the tip of the beam portion 17b and feeding the rotary cutter 17c forward. In addition, since the backfilling material supply device 16 and the suspension device 17 are arranged below the covering member 10 of the protector 11, the backfill material 3 and the support work 4 are removed while the ground surface is being ground. Even in the case where the rock pieces are peeled off from G1, the rock pieces do not hit the covering member 10 and fall into the devices 16 and 17.

  Next, when the backfilling material 3 and the support 4 in the predetermined section are removed as described above, the propulsion mechanism 15 is driven to extend at the stage where the suspended concrete pieces are transported and removed, that is, the protector. 11 and the bearing plate 14 are driven to increase the distance. At this time, the support plate 14 advances forward (moves to the backfill side) in the direction of the axis O1 of the disposal tunnel 2 in advance by the dead weight of the protector 11, and the backfill material 3 thrown in the back surface 14c of the support plate 14 is It is pressed and gradually compacted. Further, the support plate 14 advances so as to compact the backfill material 3, and the backfill material holding plate 24 installed on the steel rod 22 is pressed by the back surface 14 c of the support plate 14. Thereby, the backfilling material holding plate 24 slides on the steel rod 22 and moves while being guided by the steel rod 22 to the rear side in the direction of the axis O <b> 1 of the disposal tunnel 2. Then, the backfill material holding plate 24 is tightened when the compaction degree of the backfill material 3 reaches a predetermined compaction level and the movement of the bearing plate 14 is stopped by the reaction force from the compacted backfill material 3. It is pressed against the front surface 3 a of the hardened backfill material 3.

  When the propulsion mechanism 15 is further driven in this state, the reaction force is secured by the compacted backfill material 3, the column support member 20 of the protector 11 starts to slide on the bottom surface G <b> 2 of the disposal tunnel 2, and the protector 11. Propels forward in the direction of the axis O1 of the disposal tunnel 2. As a result, the protector 11 is propelled so as to cover the predetermined section where the support 4 has been previously suspended with the covering member 10, and the backfilling material supply device 16 and the suspension device 17 are moved to a predetermined position in the protector 11. .

  In this way, when the backfilling material 3 is compacted and the protector 11 is propelled by the extension drive of the propulsion mechanism 15, the compacted backfilling material 3 is supported by the support plate 14 in contact with the front surface 3 a. ing. In the present embodiment, in a state where the backfill material 3 thus compacted is supported by the pressure bearing plate 14, the operator screws the nut 23 screwed into the other end 22 c side of the steel rod 22. And since the through-hole 14e of the bearing plate 14 is formed larger than the nut 23, it exposes to the axis O1 direction front side (the protector 11 side, the excavation direction side of the support work 4) of the disposal tunnel 2 by this through-hole 14e. The nut 23 that has passed through the through hole 14e comes into contact with the one surface 24a of the backfill material holding plate 24 that has been made. As a result, the backfilling material holding plate 24 is sandwiched between the front surface 3 a of the backfilling material 3 and the nut 23 and is fixed to the steel rod 22 while being pressed against the front surface 3 a of the backfilling material 3.

  Further, at this stage, one end 22a of the new steel rod 22 is connected to the other end 22c of the steel rod 22 arranged on the protector 11 side with respect to the bearing plate 14 by using a coupler or the like, for example. 22 is extended in the direction of the axis O1 of the disposal tunnel 2.

  Next, the propulsion mechanism 15 is driven to be contracted, and the support plate 14 is moved (retracted) so as to approach the protector 11 side. As a result, a space (rear space) 12 into which the backfill material 3 is newly introduced is formed between the compacted front surface 3a of the backfill material 3 and the back surface 14c of the bearing plate 14. A space 12 having a predetermined thickness (thickness in the direction of the axis O1) is formed at a stage where the distance between the protector 11 and the bearing plate 14 is minimized by shrinking 15.

  Here, in the conventional tunnel closing device, as described above, the space 12 into which the backfill material 3 is newly introduced by moving the bearing plate 14 toward the protector 11 (withdrawing forward in the direction of the axis O1 of the disposal tunnel 2). When the material is formed, there is no support for the compacted backfill material 3, so that the front surface 3 a of the backfill material 3 collapses, and the compactness (density) of the backfill material 3 becomes uneven. There was a problem. In particular, the backfill material 3 as in this embodiment is used to ensure the balance of the length of the suspension removal section of the backfill section and the support work 4 and the stability of the natural ground G in the unsupported state of the backfill section. Although it is desirable to make the front surface 3a substantially vertical, in this case, the backfill material 3 is likely to collapse.

  On the other hand, in this embodiment, since the backfilling material holding plate 24 is fixed to the front surface 3a of the backfilling material 3 in a pressed state, a space 12 for newly introducing the backfilling material 3 is formed. Even when the support plate 14 is moved (retracted) to the protector 11 side, the compacted front surface 3 a of the backfill material 3 is securely held by the backfill material holding plate 24. This reliably prevents the backfill material 3 compacted with a predetermined degree of compaction from collapsing. Then, the backfilling material holding plate 24 is installed in the new space 12, and as described above, the removal of the supporter 4 on the front side, the compaction of the backfilling material 3, and the promotion of the protector 11 are sequentially repeated. As a result, the disposal tunnel 2 is backfilled with the backfilling material 3 that is reliably compacted at a predetermined degree of compaction, and the disposal tunnel 2 is preferably closed.

  Therefore, according to the mine closing method and the mine closing device B of the present embodiment, the steel rod 22 embedded and supported on the backfill material 3 that has been compacted in advance is supported by the through hole 14e of the bearing plate 14. The backfilling material 3 can be compacted while the backfilling material holding plate 24 installed on the steel rod 22 is moved backward with the advancement of the support plate 14. Then, the backfill material holding plate 24 pressed against the front surface 3 a of the backfill material 3 is fixed to the steel rod 22 using the nut 23 in a state in which the backfill material 3 is compacted with a predetermined degree of compaction. Thus, the compacted backfill material 3 can be held. Thereby, even when the bearing plate 14 is retracted to the front side in the direction of the axis O1 of the disposal tunnel 2 so as to form a new space 12 for supplying (injecting) the backfill material 3, the backfill material 3 that has been compacted. Can be prevented from collapsing.

  Further, since the through hole 14e is formed in such a size that the nut can be inserted therethrough, the compacted backfill material 3 is supported by the bearing plate 14, that is, the bearing plate 14 is moved forward. Before retracting, the nut 23 screwed from the other end 22c side of the steel rod 22 can be tightened so as to be sandwiched between the front surface 3a of the backfilling material 3 and the nut 23 through the through hole 14e, and reliably embedded. The backfill material holding plate 24 can be fixed in a state of being pressed against the back material 3. Thereby, the backfilling material holding plate 24 can be reliably fixed to the steel rod 22 by a simple operation of tightening the nut 23, and the collapse of the backfilling material 3 compacted reliably and simply can be prevented. Can do.

  Therefore, according to the tunnel closing method and the tunnel closing device B of the present embodiment, the backfill material 3 (the front surface 3a of the backfill material 3) that has been securely compacted can be prevented from collapsing. 3 can be prevented from being unevenly filled, and the mine shaft 2 can be reliably backfilled with the backfilling material 3 having a predetermined degree of compaction (density). This makes it possible to dispose of radioactive waste in a stable state over a long period of time without incurring a reduction in the shielding performance of the radioactive material even when refilling the tunnel 2 where the radioactive waste has been disposed. The mine shaft 2 can be closed while ensuring reliability.

  Further, even if the front surface 3a of the backfilling material 3 is made substantially vertical, the backfilling material holding plate 24 can surely prevent collapse, so that the balance between the length of the backfilling section and the suspension removal section of the support work 4 and the backfilling are possible. The stability of the natural ground G in the unsupported state of the section can be secured. Furthermore, since the removal work and backfilling work of the support work 4 are not complicated, a stable construction cycle can be secured continuously. Therefore, it is possible to improve the construction efficiency while ensuring the safety during construction.

  As mentioned above, although one embodiment of the tunnel closing device B and the tunnel closing method according to the present invention has been described, the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention. is there. For example, in the present embodiment, the disposal tunnel (mineway) 2 of the waste burial disposal facility A has been described as being closed. However, for example, other tunnels 2 such as a road tunnel, a railway tunnel, a sewer, a common groove, For example, it may be applied when closing with a backfill material 3 such as earth and sand.

  In the present embodiment, the new bar-shaped member (steel bar 22) is connected to the existing bar-shaped member (steel bar 22) using a coupler. For example, the male bar at one end 22a of the new bar-shaped member 22 is used. A screw may be screwed into a female screw formed on the other end 22c of the existing rod-shaped member 22 so that the rod-shaped members 22 are connected to each other.

  Further, in the present embodiment, the rod-shaped member 22 is a steel rod and a screw rod having a male screw 22b threaded on the outer periphery thereof, but may be, for example, a resin rod-shaped member, Further, if the backfilling material holding plate 24 can be fixed at the stage where the backfilling material 3 is compacted and the movement of the pressure bearing plate 14 is stopped, the rod-shaped member is backfilled using a nut 23 as a screw rod. The material holding plate 24 may not be fixed.

It is a sectional side view showing the state where the tunnel closing device concerning one embodiment of the present invention has been arranged in the tunnel. FIG. 2 is a view taken along line XX in FIG. 1. It is a perspective view showing a tunnel closing device concerning one embodiment of the present invention. It is a perspective view which shows the bearing plate of the mine closure apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the backfilling material holding | maintenance board used for the tunnel closing method which concerns on one Embodiment of this invention. It is a perspective view which shows a waste burial disposal facility. It is a perspective view which shows the main tunnel of the waste burying disposal facility of FIG. 6, and a disposal tunnel.

Explanation of symbols

1 Main tunnel 2 Disposal tunnel (tunnel)
3 Backfill 3a Front 4 Support (concrete)
DESCRIPTION OF SYMBOLS 11 Protector 12 Back space 13 Front space 14 Bearing plate 14a Front surface 14b Window portion 14c Back surface 14e Through hole 15 Propulsion mechanism (horizontal jack)
16 Backfill material supply device 17 Lifting device 22 Steel bar (bar-shaped member)
22a One end 22b Male screw 22c The other end 23 Nut 24 Backfill material holding plate 24a Slit A Waste disposal facility B Tunnel closing device G Ground mountain O1 Axis of the tunnel

Claims (4)

A bearing plate provided so as to be capable of advancing and retreating in the axial direction so as to divide the inside of the mine into a space on the front side in the axial direction of the mine shaft and a space on the rear side is advanced to the rear side in the axial direction. In the tunnel closing method in which the backfill material supplied to is pressed on the back surface of the bearing plate and compacted to backfill the tunnel,
The bearing plate includes a window portion that communicates both the front and rear spaces, and a through-hole through which a rod-like member that is supported at one end on the space side on the rear side,
While supporting the back member on the back side of the bearing plate through the window and installing the back material holding plate, supplying the back material to the rear space,
Moving the backfilling material holding plate pressed on the back surface of the pressure bearing plate together with the backfilling material by the advancement of the pressure bearing plate while moving the backside in the axial direction while guiding the rod-shaped member;
The backfill material holding plate is fixed to the rod-shaped member at a stage where the backfill material is compacted by the support plate, and the backfill material compacted by the backfill material holding plate is held. How to close the tunnel. In the mine shaft closing method according to claim 1,
The rod-shaped member is a screw rod having a male screw thread on the outer periphery, and the backfill material holding plate is fixed to the rod-shaped member by a nut screwed into the rod-shaped member. . A mine closing device for supplying backfill material into a mine shaft and compacting it to refill the mine shaft,
The inside of the tunnel is divided into a space on the front side in the axial direction of the tunnel and a space on the rear side in the axial direction for supplying the backfill material, and a bearing plate provided to be able to advance and retreat in the axial direction. And
The pressure bearing plate includes a window portion that allows communication between both the front side space and the rear side space, and a through-hole through which a rod-like member that is supported at one end side on the rear side space side passes. apparatus. The tunnel closing device according to claim 3,
The rod-shaped member is a screw rod having a male screw thread on the outer periphery, and the through-hole is large enough to allow a nut screwed from the other end side of the rod-shaped member disposed in the space on the front side to be inserted. A mine closing device characterized by being formed by

Images