JP2023004603A - Gap filler drilling device and method for drilling gap filler - Google Patents

Abstract

To provide a gap filler drilling device and a method for drilling a gap filler, for efficiently drilling a filler that blocks gaps between a plurality of containers for storing radioactive wastes and wall holes when the containers are arranged laterally in the underground tunnel.SOLUTION: The present invention relates to a gap filler drilling device 60 for drilling a filler J in gaps S between around a plurality of containers 30 for storing radioactive wastes and an underground tunnel 20, the containers 30 being laterally arranged intermittently or continuously in an axial direction of the underground tunnel 20. The gap filler drilling device includes: a base machine 40, which travels across the containers 30 laterally arranged in the underground tunnel 20; and drilling means 50A (50) equipped to the base machine 40, for drilling the filler J.SELECTED DRAWING: Figure 2

Description

The present invention relates to a gap filler excavating device and a gap filler excavating method.

High-level radioactive waste (hereinafter referred to as radioactive waste) is melted together with frit to form a vitrified body. The vitrified body is housed in a steel overpack. ), the PEM is placed inside a cushioning material that fills the inside of a hollow cylindrical steel containment container, and is emplaced in an underground tunnel (disposal tunnel) in a deep underground layer (e.g., 300m or deeper) that constitutes the final disposal site. It is considered to be treated in the stratum by being The overpack has the effect of suppressing groundwater contact with the vitrified material and protecting the vitrified material from external pressure. On the other hand, the buffer material is a mixture of bentonite and silica sand that is compression-molded to a specified density. It has the effect of protecting the vitrified material by its buffering function and chemical buffering function.
At the final disposal site, a vertical shaft extending from the surface to a deep underground layer is constructed, and a plurality of underground tunnels extending horizontally, for example, are constructed from the vertical shaft. Subterranean tunnels in which PEMs are emplaced act as natural barriers created, for example, by excavating rock mass. On the other hand, the overpack, buffer and PEM act as engineered barriers within which the radioactive waste will be encapsulated and stored within multiple barriers of these natural and engineered barriers.
Regarding the emplacement of PEMs in underground tunnels, studies are being conducted mainly on the premise of horizontal installation. Here, the horizontal placement method is a stationary method in which concrete pedestals are placed in an underground tunnel, and a plurality of PEMs are laid down on each pedestal and fixed.
On the other hand, regarding the stationary overpack, studies are being conducted mainly on the premise of a vertical placement method. In the vertical installation method, for example, a plurality of vertical holes (disposal holes) are created at intervals in the longitudinal direction of an underground tunnel that extends horizontally for several hundred meters or more, and each disposal hole is overlaid. It is being studied as a stationary method for storing packs and block-shaped cushioning materials.
Regardless of whether the installation method is vertical or horizontal, for example, the inflow of groundwater into the engineered barrier is suppressed to ensure the quality of the engineered barrier after it is set up, and to ensure the stable PEM and overpack placement posture. To ensure this, it is being considered to close the gaps between the tunnel walls (or disposal holes) and the PEM and overpack with a filler (or backfill). Clay-based materials such as granular bentonite, spherical bentonite, and other pellet-shaped bentonites (single bentonite, mixed material with bentonite as the main component) will generally be used for this filler. It is

After the PEMs and overpacks have been geologically treated at the final disposal site, from the perspective of continuing rational safety management, the government will ensure the recovery of the PEMs and overpacks containing radioactive waste until the final disposal site is closed. policy mandated. Therefore, in the geological treatment of radioactive waste, there are two stages: placing PEM, etc. in an underground tunnel and closing the gap between the hole wall and the PEM, etc. with filler; Since there is a stage for recovering the PEM inside the filler, it is necessary to develop techniques for closing the gap and removing the gap filler corresponding to both stages.

By the way, among the above-described PEM emplacement methods, the horizontal emplacement method can eliminate the need to create a disposal pit separate from the underground tunnel unlike the vertical emplacement method, so more efficient geological treatment can be realized. enable Also, when excavating and removing the filling material filled in the underground tunnel, in the case of the vertical emplacement method, it is necessary to excavate the filling material sequentially for each vertical hole (disposal hole). The excavation and removal efficiency of the filling material is inevitably lower than that of the method.
Therefore, compared to the vertical installation, the horizontal installation method is better in either the stage of closing the gap in the underground tunnel with the filling material or the stage of excavating and removing the filling material to recover the PEM inside the filling material. can also work efficiently.
However, even when the horizontal emplacement method is applied, it is difficult to excavate and remove the filling material that blocks the gap around one PEM and fill the surrounding space for underground tunnels with a length of several hundred meters or more. In a method in which the recovery of the PEM from which the material has been excavated and removed is regarded as one construction unit, and this construction unit is sequentially repeated from the opening side of the underground tunnel (connection side with the vertical shaft) toward the face side (back side), filling The reduction in work efficiency is a problem, including the need to replace the equipment for excavating and removing the material and the equipment for carrying out the PEM each time.
Therefore, from the hole mouth side of the underground tunnel, the filling material that closes the gap around the plurality of PEMs (containers containing radioactive waste) is continuously excavated, and the surrounding filling material is excavated and removed. In this work, in a state in which multiple PEMs have already been placed horizontally, the filling material blocking the gaps around the multiple PEMs is continuously excavated. However, such technology has not yet been established.
Therefore, in a state in which a plurality of PEMs are horizontally placed in an underground tunnel, there is a demand for a technique that can efficiently excavate the filling material blocking the gaps between the plurality of PEMs and the hole walls.

Here, Patent Literature 1 proposes a method for recovering a waste body in which a waste body in which radioactive waste is enclosed is taken out from a cushioning material. Specifically, in the method of recovering radioactive waste in an overpack formed in the shape of a truncated cone from an engineered barrier structure in which the waste is embedded in cushioning material, the overpack After removing the cushioning material covering the large-diameter side end face so that the large-diameter side end face is exposed, a torque along the material axis of the waste body is applied to the waste body, and spreads to the peripheral surface of the overpack and its surroundings. This is a method of recovering the waste body by cutting off the adhesion to the cushioning material and then pulling out the waste body.

JP 2015-230266 A

According to the waste collection method described in Patent Document 1, the waste containing radioactive waste can be safely and quickly removed from the cushioning material without generating new radioactive waste. They say they can.
However, since the waste body described in Patent Document 1 is subjected to stratum treatment by the above-described vertical placement method, the excavation and removal efficiency of the filler is inherently lower than that of the horizontal placement method as described above. In addition to the above-mentioned problem, that is, in a state in which a plurality of PEMs are horizontally placed in an underground tunnel, a technique that can efficiently excavate the filling material that blocks the gap between the plurality of PEMs and the hole wall. It is not a proposal.

The present invention efficiently excavates a filling material blocking a gap between a plurality of storage containers containing radioactive waste and a hole wall in a state in which a plurality of storage containers containing radioactive waste are horizontally placed in an underground tunnel. It is an object of the present invention to provide a gap filler excavating device and a gap filler excavating method capable of

In order to achieve the above object, one aspect of the gap filler excavator according to the present invention is
A plurality of storage containers containing radioactive waste are placed intermittently or continuously in the axial direction of the underground tunnel, and the gap between the periphery of the plurality of storage containers and the underground tunnel is filled. A gap filler excavator for excavating a filler, comprising:
a base machine that runs across the container horizontally placed in the underground tunnel;
and excavating means attached to the base machine for excavating the filling material.

According to this aspect, the excavating means for excavating the filling material is equipped with respect to the base machine that travels across a plurality of containment vessels (PEMs) containing radioactive waste placed horizontally in the underground tunnel. As a result, while the base machine travels over a plurality of containers, it is possible to continuously and efficiently excavate the filling material that closes the gaps around them.
Here, "a plurality of containment vessels are intermittently or continuously laid horizontally in the axial direction of the underground tunnel" means that the base machine can travel across the plurality of containment vessels in the direction perpendicular to the axis. A form in which a plurality of storage containers are positioned in the horizontal direction of the cross section (cross section), for example, at the center position or approximately the center position, and are continuously placed horizontally without gaps in the axial direction of the underground tunnel. It includes both axially spaced and intermittent transverse configurations. The cross-sectional shape of the underground tunnel includes, for example, a circular shape, an elliptical shape, and a horseshoe shape, which is an example of an irregular cross-section.
There are various forms of the excavating means, and a suitable form of excavating means is selected and mounted, for example, in front of the base machine in the running direction. The specific form of the excavation means is the cross-sectional shape and cross-sectional dimensions of the underground tunnel, the cross-sectional dimensions of the container, and the frame on which the container is placed (a unique frame for each container, or a frame extending in the axial direction of the underground tunnel). The selection is made according to the continuous rail mount) and the like. Examples of excavating means include cutter bits, disk cutters, horizontal boring machines, vibratory crushers, hydraulic crushers, and the like.

In addition, the filler excavated by the excavating means can be loaded into a crawler dump, etc., carried out, carried out by vacuum transportation, mud transportation, etc., carried out by a belt conveyor, etc. It is carried out from the underground tunnel to the vertical shaft in the carrying-out mode, and is carried out to the ground via the vertical shaft.

In another aspect of the gap filler excavator according to the present invention,
The excavation means includes a swing boom mounted on the base machine so as to be capable of turning vertically and horizontally, and a tip of the swing boom, which rotates about the axis of rotation of the swing boom or the axis of rotation perpendicular to the axis. and a rotatably mounted cutter head.

According to this aspect, the load header having the swing boom and the cutter head rotatably attached to the tip of the swing boom is applied as the excavating means, thereby avoiding interference with the container and the frame. However, only the filling material around the container can be efficiently excavated. Here, at the tip of the swing boom, the load header has a cutter head that rotates about the axis of rotation of the swing boom and a cutter head that rotates about the axis of rotation perpendicular to the axis of the swing boom. , either of which may be applied. Also, a twin cutter head (twin header) having two cutter heads may be applied.

In another aspect of the gap filler excavator according to the present invention,
The excavating means has a doughnut-shaped cutter head in a front view, which is rotatably mounted on the base machine.

According to this aspect, for example, a donut-shaped cutter head in a front view having an inner diameter approximately equal to the outer diameter of the container having a circular cross section is applied, and the filling material is excavated while rotating this cutter head. , the filling material around the containment vessel can be efficiently excavated without the need for any special controls or manipulations.
In addition, in this embodiment, a belt conveyor or the like is provided behind the hollow of the doughnut-shaped cutter head (pit side) so that the filling material excavated by the rotating cutter head is continuously fed into the hollow of the cutter head. It is possible to drop it on a belt conveyor or the like that extends backward from the bottom and carry it out to the vertical shaft. Furthermore, since it is possible to excavate and carry out the filling material around the container, and to carry out (recover) the containing container by a belt conveyor or the like extending backward from the hollow of the cutter head, excavation of the filling material And continuous work from carrying out to carrying out of the storage container can be realized.
In addition, in the process of rotating the doughnut-shaped cutter head to excavate the filling material around the container, the frame supporting the container is also excavated. For example, it is desirable to be formed of a fiber-reinforced plastic material containing glass fiber or carbon fiber. As described above, even if the pedestal is excavated, the storage container is placed on a belt conveyor or the like that extends from the hollow in the center of the cutter head to the wellhead side and is transported out. It is possible to carry out the excavated filling material and the subsequent carrying out of the container without the need to grip the container with a holding device or the like.

In another aspect of the gap filler excavator according to the present invention,
further comprising a gripper that takes a reaction force on the tunnel wall of the underground tunnel;
The filling material is excavated by the cutter head while applying a reaction force to the hole wall by the gripper.

According to this aspect, when the filler is excavated by the donut-shaped cutter head when viewed from the front, the gripper exerts a reaction force on the tunnel wall of the underground tunnel, thereby ensuring good excavation performance by the cutter head.

In another aspect of the gap filler excavator according to the present invention,
The excavating means is characterized in that it has a plurality of mutually juxtaposed cutter heads, each of which rotates about its own axis of rotation.

According to this aspect, by excavating the filling material with a plurality of cutter heads (multi-axis rotating cutter heads) that are arranged side by side and rotate around their own rotation axes, for example, a pedestal that supports the container Without interfering with (drilling) the filling material around the containment vessel can be efficiently drilled without the need for any special controls or manipulations. For example, a configuration in which a plurality of cutter heads with a small cross section having a diameter equal to the distance between the container and the hole wall of the underground tunnel is installed side by side can be mentioned. Alternatively, a parallel link mechanism may be used to move a plurality of cutter heads each having a small cross-section within a plane (multi-axis rotary-revolution cutter head). In this way, the multi-axis rotary cutter head and the multi-axis rotary/revolution cutter head enable excavation of underground tunnels with various irregular cross-sections.

In addition, one aspect of the gap filler excavation method according to the present invention is
A plurality of storage containers containing radioactive waste are placed intermittently or continuously in the axial direction of the underground tunnel, and the gap between the periphery of the plurality of storage containers and the underground tunnel is filled. A gap filler excavating method for excavating a filler,
The gap filling material excavating device includes a base machine that runs across the container placed horizontally in the underground tunnel, and excavating means that is attached to the base machine and excavates the filling material. The filling material is excavated by the excavating means while traveling in a posture straddling the container.

According to this aspect, the gap filling material excavating device travels across a plurality of containers containing radioactive waste placed horizontally in an underground tunnel and excavates the surrounding filling material, thereby excavating a plurality of containers. It is possible to continuously and efficiently excavate and remove the filling material closing the gap around the container.

According to the gap filler excavating apparatus and the gap filler excavating method of the present invention, in a state in which a plurality of containers containing radioactive waste are placed horizontally in an underground tunnel, the gaps between the plurality of containers and the hole walls are removed. It is possible to efficiently excavate the filling material blocking the .

A plurality of storage containers are horizontally placed inside an underground tunnel that constitutes a final disposal site to which the gap filler excavator according to the embodiment is applied, and a filler is placed in the gap between the hole wall of the underground tunnel and the storage container. is a diagram showing a state in which is filled. 1 is a side view showing a state in which an example of a gap filler excavating apparatus according to a first embodiment excavates a filler while running across a plurality of containers inside an underground tunnel; FIG. It is a figure explaining an example of an excavation method together. FIG. 3 is a view taken along the line III-III in FIG. 2, and is a front view of the gap filler excavating device as seen from the far side of the underground tunnel. FIG. 10 is a side view showing a state in which an example of a gap filler excavating apparatus according to a second embodiment excavates a filler while running across a plurality of containers inside an underground tunnel; It is a figure explaining the other example of an excavation method together. FIG. 5 is a view taken along line VV in FIG. 4 and is a front view of the gap filler excavating device as seen from the far side of the underground tunnel.

A gap filler excavating device and a gap filler excavating method according to each embodiment will be described below with reference to the accompanying drawings. In addition, in the present specification and drawings, substantially the same components may be denoted by the same reference numerals, thereby omitting duplicate descriptions.

[Gap Filler Excavating Device and Gap Filler Excavating Method According to First Embodiment]
First, referring to FIG. 1, the internal structure of an underground tunnel in which a filler is excavated by a gap filler excavating apparatus according to an embodiment will be described. An example of the gap filler excavating device and the gap filler excavating method will be described. Here, FIG. 1 shows a structure in which a plurality of storage containers are horizontally placed inside an underground tunnel that constitutes a final disposal site to which the gap filler excavating device according to the embodiment is applied. It is a figure which shows the state by which the filler is filled in the clearance gap between. FIG. 2 is a side view showing a state in which an example of the gap filler excavating apparatus according to the first embodiment excavates the filler while running across a plurality of containers inside the underground tunnel. FIG. 3 is a diagram illustrating an example of a method for excavating a gap filler, and FIG. 3 is a view taken along the line III-III in FIG. It is a diagram.

As shown in FIG. 1, at the final disposal site, a plurality of vertical shafts 10 (one of which is shown in FIG. 1) leading to a deep underground bedrock layer G are constructed. In the layer G, for example, an underground tunnel 20 extending horizontally and extending several hundred meters is constructed. The underground tunnel 20 is constructed by applying shotcrete to the walls of a hole created by excavating the bedrock G, and by applying steel shoring and rock bolts (not shown) as necessary.

The underground tunnel 20 in the illustrated example has a horseshoe-shaped cross-sectional shape in the direction orthogonal to the axial direction, and an invert 22 made of reinforced concrete is constructed below. Here, as for the cross-sectional shape of the underground tunnel, various shapes such as a circle, an ellipse, and a rectangle can be applied in addition to the illustrated examples.

Above the invert 22, a plurality of storage containers 30 are positioned at the center position or approximately the center position in the lateral direction in the cross section of the underground tunnel 20 in the direction orthogonal to the axis, and intermittently spaced apart from each other at intervals T in the axial direction of the underground tunnel 20. placed horizontally. Here, the storage containers 30 may be horizontally placed continuously without the interval T. FIG.

This storage container 30 is a PEM containing radioactive waste, and is a processing form in which a plurality of PEMs are laid horizontally for geological treatment. The interior of the hollow cylindrical steel PEM 30 is filled with a buffer material 31, and a steel overpack 32 that encloses a vitrified material 33 made by melting radioactive waste together with glass raw materials serves as a buffer. It is housed inside the material 31 .

A plurality of (two in the illustrated example) pedestals 25 are placed on the invert 22 , and the container 30 is placed horizontally on the pedestals 25 . Here, the pedestal may be a frame pedestal in which a plurality of steel frames are assembled in a frame shape, or may be, for example, two rails extending continuously in the axial direction of the underground tunnel 20. When a pedestal is used, wheels are provided below each storage container 30 so that each storage container 30 can be transported to a predetermined position in the underground tunnel 20 along the rail pedestal.

By placing the container 30 horizontally at the center of the cross section of the underground tunnel 20 in this way, the base machine 40 constituting the gap filler excavator 60 (see FIGS. 2 and 3) straddles the container 30. When moving, a space can be secured on the right and left sides of the storage container 30 for the traveling means 43 to move.

As shown in FIG. 1, the space between the plurality of containers 30 intermittently placed at intervals T inside the underground tunnel 20 and the hole wall of the underground tunnel 20, including the interval T, is A gap S exists, and the gap S is closed by filling the gap S with the filler J.

The filler J to be applied is a clay-based material typified by pellet-shaped bentonite such as granular bentonite and spherical bentonite. As shown in FIG. 1, the gap S between the underground tunnel 20 and the container 30 is blocked by the filler J, thereby suppressing, for example, groundwater from flowing into the artificial barrier formed by the underground tunnel 20. Therefore, it is possible to ensure the quality of the storage container 30, which is an artificial barrier after being placed horizontally, and to ensure a stable stationary posture of the storage container 30.

Next, an example of a gap filler excavating device 60A for excavating the filler J filled in the gap S of the underground tunnel 20 and a gap filler excavating method using this gap filler excavating device 60A will be described.

As shown in FIGS. 2 and 3, the gap filler excavator 60A is equipped with a base machine 40 that travels across a plurality of containers 30 that are horizontally placed in the underground tunnel 20, and the base machine 40. It has a load header 50A (an example of excavation means).

The base machine 40 includes an operator cabin 41, a plurality of (two in the illustrated example) crossover legs 42 fixed to the lower part of the operator cabin 41, and a lower end of the crossover legs 42. It has a crawler 43 (an example of a traveling means).

Excavation of the filling material J in the underground tunnel 20 is performed by driving the load header 50A while the base machine 40 travels in the X1 direction from the mouth of the underground tunnel 20 toward the back side. A swing boom 51 that constitutes the load header 50A is mounted in front of the base machine 40 in the traveling direction so that it can freely swing in the Y1 direction, which is the vertical direction, and in the Y2 direction, which is the horizontal direction. there is

A rotating shaft 52 extending in a direction orthogonal to the axial direction of the swing boom 51 (direction L in FIG. 2) is attached to the tip of the swing boom 51, and a cutter head 53 rotatable in the Y3 direction is attached to the rotating shaft 52. is installed. As shown in FIG. 3, the illustrated cutter head 53 is a twin header. Here, the excavating means may have a form in which a cutter head is attached to a rotating shaft extending in the axial direction of the swing boom.

An operator riding in the operator cabin 41 moves the base machine 40 in a posture straddling the container 30, stops it at a predetermined position, and then drives the cutter head 53 to control the swinging of the swing boom 51 as desired. As a result, the filling material J blocking the space between the container 30 and the hole wall is excavated in sequence.

In FIG. 2, the filler material J in the right area of the gap filler excavator 60A has already been excavated, and the filler material J in the left area has been excavated by the load header 50A. Although illustration is omitted, after the filler J around the plurality of storage containers 30 is continuously excavated by the gap filler excavator 60A, the excavated filler J is loaded into a crawler dump or the like and carried out. Alternatively, it may be carried out by vacuum transportation, muddy water transportation, or the like, or may be carried out by a belt conveyor installed behind the gap filler excavating device 60 .

For example, the filling material J around ten containers 30 is continuously excavated by the gap filling material excavating device 60A, and the excavated filling material J is sequentially carried out to the tunnel mouth side, and the filling material J is removed. Approximately 10 containers 30 that are exposed to the pit are continuously carried out to the pit mouth side using a crawler dump, a belt conveyor, or the like.

According to the gap filler excavating device 60A and the gap filler excavating method to which this device is applied, the base machine 40 traveling across the plurality of containers 30 containing radioactive waste placed horizontally in the underground tunnel 20 On the other hand, since the excavating means 50A for excavating the filling material J is mounted, the base machine 40 travels across the plurality of containers 30, and continuously cuts the filling material J closing the gaps S around them. can be drilled effectively and efficiently.

[Gap Filler Excavating Device and Gap Filler Excavating Method According to Second Embodiment]
Next, an example of a gap filler excavating device and a gap filler excavating method according to a second embodiment will be described with reference to FIGS. 4 and 5. FIG. Here, FIG. 4 is a side view showing a state in which an example of the gap filler excavating device according to the second embodiment is excavating the filler while traveling across a plurality of containers inside the underground tunnel. FIG. 5 is a diagram illustrating another example of the gap filler excavating method, and FIG. 5 is a view taken along line VV in FIG. It is the front view seen.

The gap filler excavator 60B has multi-axis rotary cutter heads 50B and 50C forming a horseshoe-shaped irregular cross-section excavator as excavating means in front of the base machine 40 in the traveling direction similar to the gap filler excavator 60A. are doing. Each of the cutter heads 50B and 50C having different planar dimensions has its own rotating shaft 55, and each cutter head 50B and 50C rotates in the Y4 direction, which is clockwise or counterclockwise, so that the container 30, the pedestal 25, and the hole are rotated. A filler J between the walls is excavated.

As shown in the figure, a plurality of multi-rotating cutter heads 50B and 50C are arranged so as to cover the gap S between the container 30 and the pedestal 25 and the hole wall (filler J closing the gap). Thus, the filling material J can be efficiently excavated in the process of running the base machine 40 while driving all the cutter heads 50B and 50C. That is, when excavating the filling material J having various irregular cross-sections such as the horseshoe shape in the illustrated example, no skillful operation by the operator is required.

Although illustration is omitted, a multi-axis rotation-revolution type cutter head may be applied in which a plurality of cutter heads move while rotating in the plane by a parallel link mechanism. In this form, each cutter head moves horizontally. Therefore, it is possible to excavate the filler J having an irregular cross section while reducing the number of cutter heads.

Also here, after the filler J around the plurality of containers 30 is continuously excavated by the gap filler excavator 60B, the excavated filler J is carried out by a crawler dump, a belt conveyor, or the like, and filled. The storage container 30 exposed by removing the material J is similarly carried out to the pit side using a crawler dump or the like.

[Gap filler excavator according to other embodiments]
Although illustration is omitted, an excavating apparatus having a form different from that of the gap filler excavating apparatus according to the first embodiment and the second embodiment may be used. For example, a doughnut-shaped cutter head in front view is rotatably attached to the base machine, and a gripper is attached. can be mentioned.

By equipping a belt conveyor behind the hollow of the doughnut-shaped cutter head (pit side), the filling material excavated by the rotating cutter head is continuously extended rearward from the hollow of the cutter head. It will be possible to drop it on top and carry it out to the shaft. Furthermore, since it is possible to excavate and carry out the filler around the storage container and carry out the storage container by a belt conveyor extending backward from the hollow of the cutter head, It is possible to realize continuous work up to carrying out of the container.

It should be noted that other embodiments may be possible in which other components are combined with the configurations described in the above embodiments, and the present invention is not limited to the configurations shown here. Regarding this point, it is possible to change without departing from the gist of the present invention, and it can be determined appropriately according to the application form.

10: Vertical Shaft 20: Underground Tunnel 22: Invert 25: Frame 30: Container (PEM)
31: Cushioning material 32: Overpack 33: Vitrified body 40: Base machine 41: Operator cabin 42: Crossover leg 43: Travel means (crawler)
50: Excavating means 50A: Road header 50B, 50C: Cutter head 51: Swing boom 52: Rotating shaft 53: Cutter head (twin header)
55: Rotating shaft 60, 60A, 60B: Gap filler excavator G: Bedrock layer (bedrock)
S: Gap T: Gap J: Filler

Claims (6)

A plurality of storage containers containing radioactive waste are placed intermittently or continuously in the axial direction of the underground tunnel, and the gap between the periphery of the plurality of storage containers and the underground tunnel is filled. A gap filler excavator for excavating a filler, comprising:
a base machine that runs across the container horizontally placed in the underground tunnel;
and excavating means attached to the base machine for excavating the filler. The excavation means includes a swing boom mounted on the base machine so as to be capable of turning vertically and horizontally, and a tip of the swing boom, which rotates about the axis of rotation of the swing boom or the axis of rotation perpendicular to the axis. 2. The gap filler excavator of claim 1, comprising a rotatably mounted cutter head. 2. The gap filler excavating apparatus according to claim 1, wherein said excavating means has a doughnut-shaped cutter head rotatably mounted on said base machine. further comprising a gripper that takes a reaction force on the tunnel wall of the underground tunnel;
4. The gap filling material excavating apparatus according to claim 3, wherein the filler is excavated by the cutter head while the gripper exerts a reaction force on the hole wall. 2. The gap filler excavating apparatus according to claim 1, wherein said excavating means has a plurality of cutter heads arranged side by side, each of said cutter heads rotating around its own axis of rotation. . A plurality of storage containers containing radioactive waste are placed intermittently or continuously in the axial direction of the underground tunnel, and the gap between the periphery of the plurality of storage containers and the underground tunnel is filled. A gap filler drilling method for removing filler, comprising:
The gap filling material excavating device includes a base machine that runs across the container placed horizontally in the underground tunnel, and excavating means that is attached to the base machine and excavates the filling material. A method for excavating a gap filling material, characterized in that the excavating means excavates the filling material while traveling in a posture straddling a container.

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