JP7011688B2 - Ground freezing device - Google Patents

Description

The present invention relates to a device for freezing the ground around a tubular tunnel constructed in the ground.

When constructing a tubular tunnel in the ground, for example, a shield method is used. In the shield method, for example, a starting shaft and an reaching shaft are constructed in the ground, and while excavating the ground with a shield excavator from the starting shaft to the reaching shaft, the segments are tunneled one after another at the rear of the shield excavator. A tubular tunnel (lining body) is constructed by assembling in the direction to construct a segment ring and connecting adjacent segment rings in the direction of the tunnel axis. In this construction method, the shield excavator pushes the existing segment ring behind it backward with a propulsion jack, and the thrust generated as the reaction force advances while excavating the ground.

In Patent Document 1, after constructing a tunnel in the ground using a shield method, a freezing pipe is provided on the inner wall surface of the tunnel, and a refrigerant is circulated in the freezing pipe to freeze the ground around the tunnel. Is disclosed.

Japanese Unexamined Patent Publication No. 2016-160717

However, in the technique disclosed in Patent Document 1, since a freezing pipe is provided on the inner wall surface of the tunnel after assembling the segments to construct the tunnel, it takes time from the construction of the tunnel to the start of freezing of the ground around the tunnel. I needed it. In other words, it took time and effort to work in the tunnel to start freezing the ground around the tunnel.

In view of such circumstances, it is an object of the present invention to reduce the work in the tunnel for freezing the ground around the tunnel.

Therefore, the ground freezing device according to the present invention is a device that freezes the ground around a tubular tunnel constructed in the ground. A first aspect of the ground freezing device according to the present invention is a second method of communicating a first refrigerant flow pipe provided in a segment constituting a tunnel and a first refrigerant flow pipe of each of adjacent segments in the tunnel. It has a refrigerant flow pipe and a refrigerant supply device that supplies the refrigerant into the first refrigerant flow pipe and the second refrigerant flow pipe. The segment has a frame and a skin plate arranged so as to close the ground side of the frame. The first refrigerant flow pipe is arranged so as to extend and contact the surface of the skin plate on the side opposite to the ground side along the skin plate.

A second aspect of the ground freezing device according to the present invention is a plurality of first refrigerant flow pipes provided in segments constituting a tunnel, a second refrigerant flow pipe that communicates the first refrigerant flow pipes with each other, and a first refrigerant. It has a refrigerant supply device that supplies a refrigerant into the distribution pipe and the second refrigerant flow pipe . The segment consists of a frame composed of a pair of main girders and a pair of joint plates , a skin plate arranged so as to close the ground side of the frame, and a plurality of vertical columns connecting the main girders between the joint plates. With ribs . The first refrigerant flow pipe is arranged so as to extend and contact the surface of the skin plate on the side opposite to the ground side along the skin plate. Vertical ribs are arranged between the first refrigerant flow pipes, and the second refrigerant flow pipe extends so as to straddle the vertical ribs.

According to the present invention, the first refrigerant flow pipe can be provided in the segment prior to the segment assembly step (tunnel construction step), so that the work in the tunnel for freezing the ground around the tunnel can be performed. It can be reduced as compared with the conventional case.

The figure which shows the schematic structure of the ground freezing apparatus in 1st Embodiment of this invention. A perspective view showing a segment having a first refrigerant flow pipe in the first embodiment. A perspective view showing a first refrigerant flow pipe in the first embodiment. The figure which shows the schematic structure of the refrigerant flow member in the 1st Embodiment. The figure which shows the connection method of the 1st refrigerant flow pipe and the 2nd refrigerant flow pipe in the said 1st Embodiment. The figure which shows the connection pattern of the 1st refrigerant flow pipe and the 2nd refrigerant flow pipe in the 1st Embodiment. The figure which shows the modification of the connection pattern of the 1st refrigerant flow pipe and the 2nd refrigerant flow pipe in the 1st Embodiment. The figure which shows the heat insulating material which covers the refrigerant flow member in the 2nd Embodiment of this invention. A perspective view showing a segment having a first refrigerant flow pipe according to a third embodiment of the present invention. A perspective view showing a segment having a first refrigerant flow pipe according to a fourth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a ground freezing device 1 according to a first embodiment of the present invention. FIG. 2 is a perspective view showing a segment 11 having a first refrigerant flow pipe 2 in the present embodiment. In this embodiment, it is premised that the above-mentioned shield method is used when constructing a tubular tunnel (lining body) 18 (see FIGS. 5 to 7 described later) in the ground, and a plurality of segments 11 The tunnel 18 will be constructed by connecting the tunnels in the circumferential direction and the tunnel axial direction, but the construction method used when constructing the tunnel 18 is not limited to the shield method.

As shown in FIG. 1, the ground freezing device 1 has a plurality of first refrigerant flow pipes 2, a plurality of second refrigerant flow pipes 3, a refrigerant circulation pump 4, and a cooling device 5. The cooling device 5 has a liquefier 6, a condenser 7, and a cooling tower 8.
In the cooling device 5, water circulates between the condenser 7 and the cooling tower 8. In the cooling device 5, a primary refrigerant (for example, ammonia (liquefied ammonia)) circulates between the liquefier 6 and the condenser 7.

In the present embodiment, the secondary refrigerant circulates in the refrigerant circulation path returning from the liquefier 6 of the cooling device 5 to the liquefier 6 via the refrigerant circulation pump 4, the plurality of first refrigerant flow pipes 2 and the second refrigerant flow pipe 3. is doing. In the present embodiment, the secondary refrigerant is described below as carbon dioxide (liquefied carbon dioxide), but the secondary refrigerant is not limited to carbon dioxide. Further, this secondary refrigerant corresponds to the "refrigerant" of the present invention.

In the present embodiment, the above-mentioned refrigerant circulation path through which carbon dioxide as a secondary refrigerant flows includes a plurality of refrigerant flow pipe groups in which the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3 are alternately connected. It is configured so that after branching from the discharge side of the refrigerant circulation pump 4 to these refrigerant flow pipe groups, they merge and return to the liquefier 6. Here, FIG. 1 shows four groups of refrigerant flow pipes in which eight first refrigerant flow pipes 2 and seven second refrigerant flow pipes 3 are alternately connected, and the refrigerant flow pipes are shown. The number of groups and the number of first refrigerant flow pipes 2 and second refrigerant flow pipes 3 constituting the refrigerant flow pipe group are not limited to those shown in FIG.

As shown in FIG. 2, in the present embodiment, the segment 11 closes the curved rectangular steel frame 12 and the ground side of the frame 12 (the side adjacent to the ground around the tunnel 18). A steel segment comprising a steel skin plate 13 arranged in (4 in FIG. 2) and a plurality of (four in FIG. 2) vertical ribs 14. The number of vertical ribs 14 constituting the segment 11 is not limited to this. Further, in the following description, among the skin plates 13, the surface corresponding to the outer surface (ground side surface) of the tunnel 18 is referred to as the “outer surface 13a”, while the surface corresponding to the inner surface (inner wall surface) of the tunnel 18 is referred to as the “inner surface”. 13b ".

The frame body 12 is composed of a pair of main girders 15 and 15 and a pair of joint plates 16 and 16. The main girders 15 and 15 are arc-shaped steel materials, respectively, and are arranged in parallel with each other separated from each other in the tunnel axial direction. The joint plates 16 and 16 are arranged apart from each other in the circumferential direction of the tunnel, and connect the ends of the main girders 15 and 15. Here, the main girder 15 and the joint plate 16 correspond to the "plate-shaped member" of the present invention.

The plurality of vertical ribs 14 connecting the main girders 15 and 15 between the joint plates 16 and 16 are each made of steel, are arranged in parallel at intervals in the tunnel circumferential direction, and extend in the tunnel axial direction. There is.

The plurality of (for example, eight) segments 11 are connected to each other by the joint plates 16 and 16 of the adjacent segments 11 to form an annular segment ring. Further, by connecting the main girders 15 and 15 of the adjacent segment rings to each other, a tunnel (lining body) 18 extending in the tunnel axial direction is constructed.

A plurality of (five in FIG. 2) first refrigerant flow pipes 2 are attached to the inner surface 13b of the skin plate 13. The number of the first refrigerant flow pipes 2 attached to the inner surface 13b of the skin plate 13 is not limited to this.
The work of attaching the first refrigerant flow pipe 2 to the inner surface 13b of the skin plate 13 of the segment 11 is preferably performed at a factory on the ground where the segment 11 is manufactured.

In the ground freezing device 1 shown in FIG. 1, liquefied carbon dioxide, which is a secondary refrigerant flowing in the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3, is around the tunnel 18 via the skin plate 13 of the segment 11. It exchanges heat with the ground and freezes the surrounding ground by the sensible heat and latent heat of the liquefied carbon dioxide. The carbon dioxide that has been heated by heat exchange with the surrounding ground exchanges heat with the primary refrigerant in the liquefier 6 of the cooling device 5, becomes low-temperature liquefied carbon dioxide, and becomes the first liquefied carbon dioxide again via the refrigerant circulation pump 4. It is supplied into the refrigerant flow pipe 2 and the second refrigerant flow pipe 3 and circulates. Here, the refrigerant circulation pump 4 corresponds to the "refrigerant supply device" of the present invention.

The primary refrigerant of the cooling device 5 is liquefied by heat exchange with water in the condenser 7 after heat is supplied from carbon dioxide, which is a secondary refrigerant, to evaporate and vaporize in the liquefier 6 of the cooling device 5. do. Then, the water heated by the heat supplied from the primary refrigerant in the condenser 7 is cooled by the cooling tower 8.

Next, the configuration of the first refrigerant flow pipe 2 will be described with reference to FIGS. 3 and 4.
FIG. 3 is a perspective view showing the first refrigerant flow pipe 2 in the present embodiment. FIG. 4 is a diagram showing a schematic configuration of the refrigerant distribution member 20 in the present embodiment. Here, FIG. 4A is a perspective view of the refrigerant flow member 20, and FIG. 4B is a cross-sectional view of the refrigerant flow member 20.

As shown in FIG. 3, the first refrigerant flow pipe 2 is composed of a refrigerant flow member 20, a pair of sockets 21a and 21b, and tubular members 22a and 22b provided in each of the sockets 21a and 21b. ..

As shown in FIG. 4, the refrigerant flow member 20 is a flat member having a plurality of (11 in FIG. 4) minute refrigerant flow paths 24, and is made of metal (for example, aluminum). That is, the refrigerant flow member 20 has a microchannel structure provided with a plurality of minute refrigerant flow paths 24. In the present embodiment, the cross-sectional shape of the minute refrigerant flow path 24 is rectangular, but the cross-sectional shape is not limited to the rectangular shape, and may be, for example, a circular shape or an elliptical shape. Further, the number of minute refrigerant flow paths 24 constituting the refrigerant distribution member 20 is not limited to 11.

In this embodiment, liquefied carbon dioxide is used as the secondary refrigerant flowing through the minute refrigerant flow path 24 of the refrigerant flow member 20. Here, liquefied carbon dioxide has a much lower viscosity than brine such as an aqueous solution of calcium chloride or an aqueous solution of sodium chloride. Therefore, the resistance of liquefied carbon dioxide when flowing through the minute refrigerant flow path 24 of the refrigerant flow member 20 is extremely small as compared with brine. Therefore, the flow path cross-sectional area of the minute refrigerant flow path 24 of the refrigerant flow member 20 can be made much smaller than that in the case of using brine, and thus two rectangular surfaces (as shown in FIG. 4). Flat surface) The refrigerant flow member 20 can be formed of a flat member having 20a and 20b. For example, the width w of the refrigerant distribution member 20 can be about 50 mm, and the thickness t of the refrigerant distribution member 20 can be about 5 mm (see FIG. 4A). Further, the refrigerant flow member 20 may have flexibility. In other words, the refrigerant flow member 20 is easily deformable.

As shown in FIG. 3, each of the sockets 21a and 21b has a rectangular parallelepiped box shape, has a rectangular parallelepiped internal space, and is made of metal (for example, aluminum). One end side of the refrigerant flow member 20 is connected to the socket 21a, and the minute refrigerant flow path 24 of the refrigerant flow member 20 and the internal space of the socket 21a communicate with each other. The other end side of the refrigerant flow member 20 is connected to the socket 21b, and the minute refrigerant flow path 24 of the refrigerant flow member 20 and the internal space of the socket 21b communicate with each other.

The base end portion of the tubular member 22a is connected to the socket 21a, and the connection port 23a with the second refrigerant flow pipe 3 is provided at the tip end portion. The internal space of the tubular member 22a communicates with the internal space of the socket 21a. The tubular member 22a extends along the tunnel radial direction so that the tip portion is located inside the tunnel radial direction from the proximal end portion thereof.

The base end portion of the tubular member 22b is connected to the socket 21b, and the connection port 23b with the second refrigerant flow pipe 3 is provided at the tip end portion. The internal space of the tubular member 22b communicates with the internal space of the socket 21b. The tubular member 22b extends along the tunnel radial direction so that the tip portion is located inside the tunnel radial direction from the proximal end portion thereof.

Here, one of the connection ports 23a and 23b corresponds to the "refrigerant inlet portion" of the present invention, and the other corresponds to the "refrigerant discharge port portion" of the present invention. In the present embodiment, the connection port 23a corresponds to the "refrigerant inlet portion" of the present invention, and the connection port 23b corresponds to the "refrigerant discharge port portion" of the present invention.

In the present embodiment, the refrigerant flow member 20 is attached to the inner surface 13b of the skin plate 13 so that the surface 20a of the refrigerant flow member 20 comes into contact with the inner surface 13b of the skin plate 13. When the refrigerant flow member 20 is attached to the inner surface 13b of the skin plate 13, an adhesive means such as an adhesive, a lashing means such as a band, or a fastening means such as a screw may be used.

In the present embodiment, the refrigerant flow member 20 extends along the skin plate 13 so as to come into contact with the inner surface 13b of the skin plate 13. Further, some refrigerant flow members 20 are arranged between adjacent vertical ribs 14 and extend in parallel with the vertical ribs 14. Further, some other refrigerant flow members 20 are arranged between the adjacent vertical ribs 14 and the joint plate 16 and extend in parallel with the vertical ribs 14 and the joint plate 16.
With the plurality of segments 11 assembled and the tunnel 18 constructed, the refrigerant flow member 20 extends in the direction of the tunnel axis.

Next, a method of connecting the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3 will be described with reference to FIG. FIG. 5A shows a state before the second refrigerant flow pipe 3 is connected to the first refrigerant flow pipe 2. FIG. 5A shows a state after the second refrigerant flow pipe 3 is connected to the first refrigerant flow pipe 2. FIG. 5 (c) is an enlarged view of a connecting portion between the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3.

First, as shown in FIG. 5A, the tunnel 18 is constructed by assembling the segment 11 having the first refrigerant flow pipe 2. Here, the segments 11 adjacent to each other in the tunnel axial direction in the tunnel 18 are connected to each other via an appropriate connecting means in a state where the main girders 15 are in contact with each other. Further, the segments 11 adjacent to each other in the tunnel circumferential direction in the tunnel 18 are connected to each other via an appropriate connecting means in a state where the joint plates 16 are in contact with each other.

Next, as shown in FIG. 5 (a), the connection port 23b (refrigerant discharge port) of one of the first refrigerant flow pipes 2 among the segments 11 adjacent to each other in the tunnel 18 and the other first refrigerant flow pipe. The connection port 23a (refrigerant inflow port portion) of 2 is connected via the second refrigerant flow pipe 3.

As shown in FIG. 5 (c), cylindrical joint members 26 are provided at both ends of the second refrigerant flow pipe 3. The joint member 26 is rotatable relative to the second refrigerant flow pipe 3 with the central axis of the second refrigerant flow pipe 3 as the center of rotation. A female threaded portion is formed on the inner peripheral surface of the joint member 26. Corresponding to this, a male screw portion is formed on the outer peripheral surface of the connection ports 23a and 23b of the tubular members 22a and 22b of the first refrigerant flow pipe 2. By screwing the female threaded portion on the inner peripheral surface of the joint member 26 into the male threaded portion on the outer peripheral surface of the connection ports 23a and 23b, the second refrigerant flow pipe 3 can be detachably attached to the first refrigerant flow pipe 2. The method of attaching and detaching the second refrigerant flow pipe 3 to the first refrigerant flow pipe 2 is not limited to this, and for example, the second refrigerant flow pipe 3 can be attached to and detached from the first refrigerant flow pipe 2 by a so-called one-touch joint method. It may be attached to.

Here, the second refrigerant flow pipe 3 is made of metal (for example, copper). The second refrigerant flow pipe 3 may have flexibility. In other words, the second refrigerant flow pipe 3 can be easily deformed.

FIG. 6 is a diagram showing a connection pattern between the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3 in the present embodiment. FIG. 7 is a diagram showing a modified example of the connection pattern between the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3 in the present embodiment. In FIGS. 6 and 7, the dotted line indicates the vertical rib 14, the one-dot chain line indicates the main girder 15, and the two-dot chain line indicates the joint plate 16. Therefore, in FIGS. 6 and 7, the region surrounded by the alternate long and short dash line (main girder 15) and the alternate long and short dash line (joint plate 16) corresponds to one segment 11.

In the embodiment shown in FIG. 6, the second refrigerant flow pipe 30 (second refrigerant flow pipe 3) extends so as to straddle the main girders 15 in contact with each other. The first refrigerant flow pipe 2 extends in the direction of the tunnel axis.

In the modification shown in FIG. 7, prior to assembling the segment 11 to construct the tunnel 18, a refrigerant flow pipe 29 having the same configuration as the second refrigerant flow pipe 3 is provided in the segment 11, and the first refrigerant flow pipe 2 is provided. After forming a meandering refrigerant flow path by the refrigerant flow pipe 29 and the refrigerant flow pipe 29, the segment 11 is assembled to construct a tunnel 18 (see FIG. 7A). Here, the refrigerant flow pipe 29 extends so as to straddle the vertical rib 14. The work of providing the refrigerant flow pipe 29 in the segment 11 may be performed in a factory on the ground where the segment 11 is manufactured, in the same manner as the work of attaching the first refrigerant flow pipe 2 to the skin plate 13 of the segment 11.

Next, as shown in FIG. 7 (a), the second refrigerant flow pipe 30 (second refrigerant flow pipe 3) extending so as to straddle the main girders 15 in contact with each other and the joint plates 16 in contact with each other. A second refrigerant flow pipe 31 (second refrigerant flow pipe 3) extending so as to straddle is used with a connection port 23b (refrigerant discharge port) of one of the adjacent segments 11 of the first refrigerant flow pipe 2. The other connection port 23a (refrigerant inflow port) of the first refrigerant flow pipe 2 is connected. Even in the case of forming a complicatedly meandering refrigerant flow path as shown in FIG. 7, most of the forming work can be performed in the factory on the ground where the segment 11 is manufactured, so that the forming work can be performed in the tunnel 18. The work can be greatly reduced. Also in the modified example shown in FIG. 7, the first refrigerant flow pipe 2 extends in the tunnel axial direction.

Next, a method of freezing the ground around the tunnel 18 using the ground freezing device 1 will be described.
First, as shown in FIG. 5A, the segment 11 having the first refrigerant flow pipe 2 is assembled to construct the tunnel 18.

Next, as shown in FIG. 5 (a), the connection port 23b (refrigerant discharge port) of one of the first refrigerant flow pipes 2 among the segments 11 adjacent to each other in the tunnel 18 and the other first refrigerant flow pipe. The connection port 23a (refrigerant inflow port portion) of 2 is connected via the second refrigerant flow pipe 3.
Next, liquefied carbon dioxide, which is a secondary refrigerant, is circulated in the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3, and the ground around the tunnel 18 is frozen.
In this way, the ground around the tunnel 18 is frozen.

By the way, conventionally, when a freezing pipe is provided on the inner surface of a skin plate of a tunnel segment after constructing a tunnel in the ground by using a shield method, a refrigerant flow member 20 (micro refrigerant flow) is used to use brine as a refrigerant. A metal tube such as a square tube having a much larger flow path cross-sectional area and higher rigidity than the road 24) was used as the freezing tube. In addition to this, the skin plate was sometimes deformed by the pressure of the ground after the tunnel was constructed. Therefore, when the freezing tube is provided on the inner surface of the skin plate, a filling material such as epoxy resin mortar is injected into the gap between the freezing tube and the skin plate to eliminate the gap between the freezing tube and the skin plate. It was necessary to do the work, and this work was troublesome. In this regard, according to the present embodiment, the production of the segment 11 and the installation (pasting) of the first refrigerant flow pipe 2 on the skin plate 13 can be integrally performed at the factory on the ground, and also. After the tunnel is constructed, the first refrigerant flow pipe 2 (refrigerant flow member 20) can be deformed following the deformation of the skin plate 13, so that the above-mentioned filling material injection work can be reduced.

According to the present embodiment, the ground freezing method includes a step of assembling a segment 11 having a first refrigerant flow pipe 2 to construct a tubular tunnel 18 (see FIG. 5A) and adjacent to each other in the tunnel 18. The step of connecting the first refrigerant flow pipes 2 of the segments 11 to each other via the second refrigerant flow pipe 3 (see FIG. 5A), and the inside of the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3 It includes a step of circulating a refrigerant (secondary refrigerant: carbon dioxide) therein to freeze the ground around the tunnel 18. Therefore, prior to the assembly step of the segment 11 (construction step of the tunnel 18), the first refrigerant flow pipe 2 can be provided in the segment 11, so that the ground around the tunnel 18 can be frozen in the tunnel 18. Work can be reduced compared to the conventional method.

Further, according to the present embodiment, the segment 11 is made of steel. The first refrigerant flow pipe 2 extends along the skin plate 13 so that at least a part thereof (refrigerant flow member 20) comes into contact with the skin plate 13 of the segment 11 (see FIGS. 2 and 5). Further, at least a part (refrigerant flow member 20) of the first refrigerant flow pipe 2 is attached to the inner surface 13b of the skin plate 13 of the segment 11 (see FIGS. 2 and 5). Therefore, the liquefied carbon dioxide, which is the secondary refrigerant flowing in the first refrigerant flow pipe 2, can be satisfactorily received from the ground around the tunnel 18 through the skin plate 13.

Further, according to the present embodiment, the segments 11 adjacent to each other in the tunnel 18 are connected to each other in a state where the plate-shaped members (main girder 15, joint plate 16) are in contact with each other. The second refrigerant flow pipe 3 extends so as to straddle the plate-shaped members (main girder 15, joint plate 16) in the contacted state (see FIGS. 5 to 7). As a result, the first refrigerant flow pipes 2 provided in different segments 11 can be connected to each other with a simple configuration.

Further, according to the present embodiment, the second refrigerant flow pipe 3 is detachably attached to the first refrigerant flow pipe 2 (see FIG. 5). Thereby, for example, by appropriately relocating the second refrigerant flow pipe 3 in the constructed tunnel 18, the refrigerant flow path of the liquefied carbon dioxide as the secondary refrigerant can be easily changed.

Further, according to the present embodiment, the ground freezing device 1 is a device that freezes the ground around the tubular tunnel 18 constructed in the ground. The ground freezing device 1 connects the first refrigerant flow pipe 2 provided in the segment 11 constituting the tunnel 18 and the second refrigerant flow pipe 2 of each of the adjacent segments 11 in the tunnel 18. It has a flow pipe 3 and a refrigerant supply device (refrigerant circulation pump 4) that supplies a refrigerant (secondary refrigerant: carbon dioxide) into the first refrigerant flow pipe 2 and the second refrigerant flow pipe 3. Therefore, prior to the assembly step of the segment 11 (construction step of the tunnel 18), the first refrigerant flow pipe 2 can be provided in the segment 11, so that the ground around the tunnel 18 can be frozen in the tunnel 18. Work can be reduced compared to the conventional method.

Further, according to the present embodiment, the segment 11 is arranged so as to block the steel frame body 12 composed of a plurality of plate-shaped members (main girder 15, joint plate 16) and the ground side of the frame body 12. It has a steel skin plate 13. The first refrigerant flow pipe 2 extends along the skin plate 13 so that at least a part thereof (refrigerant flow member 20) comes into contact with the surface (inner surface 13b) of the skin plate 13 opposite to the ground side. .. Further, at least a part (refrigerant flow member 20) of the first refrigerant flow pipe 2 is attached to the surface (inner surface 13b) of the skin plate 13 of the segment 11 opposite to the ground side. Therefore, the liquefied carbon dioxide, which is the secondary refrigerant flowing in the first refrigerant flow pipe 2, can be satisfactorily received from the ground around the tunnel 18 through the skin plate 13.

Next, a modification of the above-mentioned first embodiment will be described.
As shown in FIG. 2, the inner surface 13b of the skin plate 13 is a curved surface curved along the tunnel circumferential direction of the tunnel 18. For the segment 11, a minute non-landing may be formed on the inner surface 13b (curved surface) of the skin plate 13 during manufacturing at a factory on the ground. When the refrigerant flow member 20 is attached to the inner surface 13b of the skin plate 13 at a factory on the ground where the segment 11 is manufactured, a gap due to the non-landing is formed between the surface 20a of the refrigerant flow member 20 and the inner surface 13b of the skin plate 13. When this occurs, this void interferes with heat exchange between the secondary refrigerant (liquefied carbon dioxide) and the ground around the tunnel 18. Therefore, in this modification, a filler (in other words, a non-landing adjusting material or a filling material) is filled between the surface 20a of the refrigerant flow member 20 and the inner surface 13b of the skin plate 13 in the factory on the ground. It is preferable that the filling work of the filler is performed in a factory on the ground where the segment 11 is manufactured and the first refrigerant flow pipe 2 is installed (pasted) on the skin plate 13. That is, the filling operation of this filler can be performed prior to assembling the segment 11 to construct the tunnel 18. Here, as the filler (in other words, the non-landing adjusting material or the filling material), for example, an epoxy resin mortar, a cement paste, a mortar or the like can be used. A resin-based adhesive may be used as a filler (in other words, a non-landing adjusting material or a filling material). Therefore, in this modification, the refrigerant flow member 20 is attached to the inner surface 13b of the skin plate 13 with the filler interposed between the inner surface 13b of the skin plate 13. As described above, even in the refrigerant flow member 20 in which the filler is filled between the inner surface 13b of the skin plate 13 and the skin plate 13 due to the pressure of the ground after the construction of the tunnel 18 (after the assembly of the segment 11). It can be deformed according to the deformation of.

In particular, according to this modification, the segment 11 having the first refrigerant flow pipe 2 is a filler interposed between the first refrigerant flow pipe 2 and the inner surface 13b of the skin plate 13 (in other words, non-landing adjustment). It also has a material or a filling material). As a result, heat exchange between the secondary refrigerant (liquefied carbon dioxide) and the ground around the tunnel 18 can be efficiently performed.

FIG. 8 is a diagram showing a heat insulating material 28 covering the refrigerant flow member 20 in the second embodiment of the present invention.
The points different from the above-mentioned first embodiment and its modification will be described.

In the present embodiment, the work of attaching the first refrigerant flow pipe 2 to the inner surface 13b of the skin plate 13 of the segment 11 and the work of providing the heat insulating material 28 on the segment 11 so as to cover the first refrigerant flow pipe 2 are segments. It can be done in a ground-based factory that manufactures 11.
The heat insulating material 28 is provided on the segment 11 so as to cover at least the surface 20b of the refrigerant flow member 20 (the surface on the side opposite to the above-mentioned surface 20a). As the heat insulating material 28, for example, urethane foam may be used.

In particular, according to the present embodiment, prior to assembling the segment 11 to construct the tunnel 18, the heat insulating material 28 is provided in the segment 11 so as to cover the first refrigerant flow pipe 2 provided in the segment 11. As a result, the exposed portion of the first refrigerant flow pipe 2 can be reduced, so that the ground around the tunnel 18 can be efficiently frozen.

Further, according to the present embodiment, the ground freezing device 1 has a heat insulating material 28 that covers the first refrigerant flow pipe 2 provided in the segment 11. As a result, the exposed portion of the first refrigerant flow pipe 2 can be reduced, so that the ground around the tunnel 18 can be efficiently frozen.

FIG. 9 is a perspective view showing a segment 40 having a first refrigerant flow pipe 2 according to a third embodiment of the present invention.
The points different from the above-mentioned first embodiment and its modification will be described.

In the present embodiment, the concrete 41 is filled in the space surrounded by the frame body 12 and the skin plate 13. That is, the segment 40 shown in FIG. 9 is a synthetic segment, and is formed by filling the internal space of the segment 11 (steel segment) having the frame body 12, the skin plate 13, and the vertical ribs 14 with concrete 41.

In the factory on the ground where the segment 40 is manufactured, after the work of attaching the first refrigerant flow pipe 2 to the inner surface 13b of the skin plate 13, the concrete 41 is subsequently filled.

In the present embodiment, the connection ports 23a and 23b of the first refrigerant flow pipe 2 project from the inner surface 41a of the concrete 41 and are exposed. Here, the inner surface 41a of the concrete 41 is a surface that can form the inner surface (inner wall surface) of the tunnel 18.
The portion of the first refrigerant flow pipe 2 other than the connection ports 23a and 23b is embedded in the concrete 41.

In particular, according to the present embodiment, the concrete 41 is filled in the frame 12 of the segment 11 prior to assembling the segment 40 to construct the tunnel 18. The refrigerant inflow port and the refrigerant discharge port (connection ports 23a and 23b) of the first refrigerant flow pipe 2 are exposed to the outside of the concrete 41, respectively, and the remaining portion (connection ports 23a and 23b of the first refrigerant flow pipe 2) is exposed. (Other than that) is buried in the concrete 41. As a result, since the concrete 41 can function as the above-mentioned heat insulating material 28, the exposed portion of the first refrigerant flow pipe 2 can be reduced, and the ground around the tunnel 18 can be efficiently frozen.

FIG. 10 is a perspective view showing a segment 50 having a first refrigerant flow pipe 2 according to a fourth embodiment of the present invention.
The points different from the above-mentioned first embodiment and its modification will be described.

The segment 50 is an RC segment. That is, the main body 51 of the segment 50 is made of concrete.
In the factory on the ground where the segment 50 is manufactured, the portion of the first refrigerant flow pipe 2 other than the connection ports 23a and 23b is embedded in the main body 51 when the main body 51 is manufactured.

In the present embodiment, the connection ports 23a and 23b of the first refrigerant flow pipe 2 project from the inner surface 51a of the main body 51 and are exposed. Here, the inner surface 51a of the main body 51 is a surface that can form the inner surface (inner wall surface) of the tunnel 18. The outer surface 51b of the main body 51 is a surface on the side opposite to the inner surface 51a, and is a surface corresponding to the outer surface (ground side surface) of the tunnel 18.

The main body 51 is divided into two layers so as to have the same thickness in the thickness direction (tunnel radial direction), and of these two layers, the layer including the outer surface 51b is used as the first layer, and the inner surface 51a is included. When the layer is a second layer, it is preferable that the refrigerant flow member 20 is located in the first layer. That is, it is preferable that the refrigerant flow member 20 (first refrigerant flow tube 2) is located in the half of the main body 51 on the outer surface 51b side.

The surface 20a of the refrigerant flow member 20 constituting the first refrigerant flow pipe 2 is preferably located in the vicinity of the outer surface 51b of the main body 51. Further, the surface 20a of the refrigerant flow member 20 constituting the first refrigerant flow pipe 2 may be flush with the outer surface 51b of the main body 51.
In a state where the plurality of segments 50 are assembled to construct the tunnel 18, the refrigerant flow member 20 extends in the direction of the tunnel axis.

In particular, according to the present embodiment, the main body 51 of the segment 50 is made of concrete. The refrigerant inflow port and the refrigerant discharge port (connection ports 23a and 23b) of the first refrigerant flow pipe 2 are exposed to the outside of the main body 51, respectively, and the remaining portion (connection ports 23a and 23b of the first refrigerant flow pipe 2) is exposed. A portion other than the above) is embedded in the main body 51. Therefore, the ground around the tunnel 18 can be frozen by using the segment 50 in which the first refrigerant flow pipe 2 is integrated.

In the third and fourth embodiments described above, the surface 20b of the refrigerant flow member 20 (the surface opposite to the surface 20a described above) may be covered with the heat insulating material 28 described above.

Further, in the above-mentioned third and fourth embodiments, the portions of the first refrigerant flow pipe 2 other than the connection ports 23a and 23b are embedded in the concrete 41 and the main body 51, but instead of this, the refrigerant is used. The flow member 20 may be attached to the inner surface 41a of the concrete 41 and the inner surface 51a of the main body 51. Further, in this case as well, the surface 20b of the refrigerant flow member 20 (the surface on the side opposite to the surface 20a described above) may be covered with the heat insulating material 28 described above. Further, also in this case, as in the modification of the first embodiment described above, there is a filler (in other words, no filling material) between the surface 20a of the refrigerant flow member 20 and the inner surface 41a of the concrete 41 and the inner surface 51a of the main body 51. Land adjustment material or padding material) may be interposed.

Further, the heat insulating material 28 not only covers the surface 20b of the refrigerant flow member 20 (the surface opposite to the surface 20a), but also connects the sockets 21a and 21b and the tubular members 22a and 22b. Needless to say, the parts other than 23a and 23b may be covered.

Further, in the above-mentioned first to fourth embodiments, the liquefied carbon dioxide, which is a secondary refrigerant, is configured to flow in the same direction through the plurality of minute refrigerant flow paths 24 of the refrigerant flow member 20. The flow direction of liquefied carbon dioxide in a part of the plurality of minute refrigerant flow paths 24 of the refrigerant flow member 20 and the flow direction of liquefied carbon dioxide in the rest may be different from each other.

Further, in the above-mentioned first to fourth embodiments, the refrigerant flow member 20 is composed of a flat member having a minute refrigerant flow path 24, but the structure of the refrigerant flow member 20 is not limited to this.

Further, in the above-mentioned first to fourth embodiments, the first refrigerant flow pipe 2 is composed of the refrigerant flow member 20, the sockets 21a and 21b, and the tubular members 22a and 22b. The configuration is not limited to this.

Further, in the above-mentioned first to third embodiments, the first refrigerant flow pipe 2 provided on the inner surface 13b of the skin plates 13 of the segments 11 and 40 extends linearly along the skin plate 13. In addition, the first refrigerant flow pipe 2 may extend in a rectangular wavy shape or a zigzag shape along the skin plate 13.

Further, in the above-mentioned fourth embodiment, the first refrigerant flow pipe 2 provided in the main body 51 of the segment 50 extends linearly along the outer surface 51b of the main body 51, but in addition to this, the first refrigerant flow pipe 2 may extend in a rectangular wavy shape or a zigzag shape along the outer surface 51b of the main body 51.

Further, in the above-mentioned first to fourth embodiments, an example in which the tunnel 18 is constructed by the shield method using the segments 11, 40, and 50 having the first refrigerant flow pipe 2 has been described. A tunnel may be constructed by a propulsion method using an arc-shaped or ring-shaped segment having a first refrigerant flow pipe 2. That is, the segment having the first refrigerant flow pipe 2 is not limited to the arc shape, but may be a ring shape.

Further, the cross-sectional shape of the tunnel constructed by assembling the segment having the first refrigerant flow pipe 2 is not limited to a circular shape, and may be, for example, an elliptical shape or a rectangular shape.

Further, the illustrated embodiment is merely an example of the present invention, and the present invention is in addition to those directly shown by the described embodiments, and various improvements and improvements made by those skilled in the art within the scope of the claims. It goes without saying that it involves changes.
The initial claims of Japanese Patent Application No. 2017-846450 were as follows.
[Claim 1]
The process of assembling the segment having the first refrigerant flow pipe to construct a tubular tunnel,
A step of connecting the first refrigerant flow pipes of adjacent segments adjacent to each other in the tunnel via a second refrigerant flow pipe.
A step of circulating a refrigerant in the first refrigerant flow pipe and the second refrigerant flow pipe to freeze the ground around the tunnel.
Ground freezing methods, including.
[Claim 2]
The segment is made of steel
The ground freezing method according to claim 1, wherein at least a part of the first refrigerant flow pipe is attached to the inner surface of the skin plate of the segment.
[Claim 3]
The segments adjacent to each other in the tunnel are connected to each other in a state where the plate-shaped members are in contact with each other.
The ground freezing method according to claim 2, wherein the second refrigerant flow pipe extends so as to straddle the plate-shaped member.
[Claim 4]
Prior to assembling the segment and constructing the tunnel, concrete is filled in the frame of the segment.
The ground freeze according to claim 2 or 3, wherein the refrigerant inlet portion and the refrigerant discharge port portion of the first refrigerant flow pipe are exposed to the outside of the concrete, and the rest is buried in the concrete. Method.
[Claim 5]
The segment has a concrete body and is made of concrete.
The ground freezing method according to claim 1, wherein the refrigerant inlet portion and the refrigerant discharge port portion of the first refrigerant flow pipe are exposed to the outside of the main body, and the rest is embedded in the main body.
[Claim 6]
One of claims 1 to 5, wherein a heat insulating material is provided in the segment so as to cover the first refrigerant flow pipe provided in the segment prior to assembling the segment to construct the tunnel. The ground freezing method described in.
[Claim 7]
The ground freezing method according to any one of claims 1 to 6, wherein the second refrigerant flow pipe is detachably attached to the first refrigerant flow pipe.
[Claim 8]
A device that freezes the ground around a tubular tunnel constructed in the ground.
The first refrigerant flow pipe provided in the segment constituting the tunnel,
A second refrigerant flow pipe connecting the first refrigerant flow pipes of each of the adjacent segments in the tunnel, and a second refrigerant flow pipe.
A refrigerant supply device that supplies a refrigerant into the first refrigerant flow pipe and the second refrigerant flow pipe,
Has a ground freezing device.
[Claim 9]
The segment is
A steel frame composed of multiple plate-shaped members and
A steel skin plate arranged so as to block the ground side of the frame, and
Have,
The ground freezing device according to claim 8, wherein at least a part of the first refrigerant flow pipe is attached to the surface of the skin plate on the side opposite to the ground side.
[Claim 10]
The segments adjacent to each other in the tunnel are connected to each other in a state where the plate-shaped members are in contact with each other.
The ground freezing device according to claim 9, wherein the second refrigerant flow pipe extends so as to straddle the plate-shaped member in contact with the second refrigerant flow pipe.
[Claim 11]
The inside of the frame is filled with concrete,
The ground according to claim 9 or 10, wherein the refrigerant inlet portion and the refrigerant discharge port portion of the first refrigerant flow pipe are exposed outside the concrete, and the rest is buried in the concrete. Freezing device.
[Claim 12]
The segment has a concrete body and is made of concrete.
The ground freezing device according to claim 8, wherein the first refrigerant flow pipe has a refrigerant inlet portion and a refrigerant discharge port exposed to the outside of the main body, and the rest thereof is embedded in the main body.
[Claim 13]
The ground freezing device according to any one of claims 8 to 12, further comprising a heat insulating material for covering the first refrigerant flow pipe provided in the segment.
[Claim 14]
The ground freezing device according to any one of claims 8 to 13, wherein the second refrigerant flow pipe is detachably attached to the first refrigerant flow pipe.

1 Ground freezing device 2 1st refrigerant flow pipe 3 2nd refrigerant flow pipe 4 Refrigerant circulation pump 5 Cooling device 6 Liquefizer 7 Condensator 8 Cooling tower 11 Segment 12 Frame 13 Skin plate 13a Outer surface 13b Inner surface 14 Vertical rib 15 Main girder 16 Joint plate 18 Tunnel 20 Refrigerant flow member 20a, 20b Surface 21a, 21b Socket 22a, 22b Tubular member 23a, 23b Connection port 24 Micro refrigerant flow path 26 Joint member 28 Insulation material 29 Refrigerant flow pipe 30, 31 Second refrigerant flow pipe 40 Segment 41 Concrete 41a Inner surface 50 Segment 51 Main body 51a Inner surface 51b Outer surface

Claims (4)

A device that freezes the ground around a tubular tunnel constructed in the ground.
The first refrigerant flow pipe provided in the segment constituting the tunnel,
A second refrigerant flow pipe that communicates with each other of the first refrigerant flow pipes of the segments adjacent to each other in the tunnel.
A refrigerant supply device that supplies a refrigerant into the first refrigerant flow pipe and the second refrigerant flow pipe ,
Have,
The segment has a frame and a skin plate arranged so as to close the ground side of the frame.
The ground freezing device is arranged such that the first refrigerant flow pipe extends along the skin plate and comes into contact with the surface of the skin plate on the side opposite to the ground side. The frame body is composed of a plurality of plate-shaped members, and is composed of a plurality of plate-shaped members.
The segments adjacent to each other in the tunnel are connected to each other in a state where the plate-shaped members are in contact with each other.
The ground freezing device according to claim 1, wherein the second refrigerant flow pipe extends so as to straddle the plate-shaped members in contact with each other. A device that freezes the ground around a tubular tunnel constructed in the ground.
A plurality of first refrigerant flow pipes provided in the segments constituting the tunnel, and
A second refrigerant flow pipe that communicates the first refrigerant flow pipes with each other,
A refrigerant supply device that supplies a refrigerant into the first refrigerant flow pipe and the second refrigerant flow pipe ,
Have,
The segment connects the main girders to each other between a frame body composed of a pair of main girders and a pair of joint plates , a skin plate arranged so as to close the ground side of the frame body, and the joint plates. With multiple vertical ribs ,
The first refrigerant flow pipe is arranged so as to extend and contact the surface of the skin plate on the side opposite to the ground side along the skin plate .
The vertical ribs are arranged between the first refrigerant flow pipes, and the vertical ribs are arranged.
The second refrigerant flow pipe is a ground freezing device extending so as to straddle the vertical ribs . The ground freeze according to any one of claims 1 to 3, further comprising a filler interposed between the surface of the skin plate on the side opposite to the ground side and the first refrigerant flow pipe. Device.

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