JP3774595B2 - Construction method of underground hollow structure and cylindrical bag body for construction of underground hollow structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing an underground hollow structure and a cylindrical bag body for constructing an underground hollow structure, and more specifically, concrete is cast in a groove formed in the ground, etc. The present invention relates to a method for constructing a hollow structure and a cylindrical bag used for the construction.
[0002]
[Prior art]
Conventionally, to construct a culvert made of concrete structure, excavating the ground to form a long groove, partitioning the long groove in the longitudinal direction, installing a formwork, placing ready-mixed concrete in the formwork and hardening By constructing, a part of the underdrain was constructed, and this part of the underdrain was successively constructed many times in succession so as to be continuous in the longitudinal direction. The number of repetitions varies depending on the length of the underdrain, but in the case of a long underdrain that exceeds 1 km, it is several tens of times.
[0003]
In the construction of such a culvert, the formwork for forming the external shape of the culvert and the formwork for forming the inner wall surface are assembled and installed as many times as necessary, and removed after the concrete has hardened. Since this formwork is strong enough to withstand the weight and pressure of concrete, the installation and removal of the formwork is a labor-intensive work and a heavy labor. Therefore, repeating such work many times has caused an increase in construction period and construction cost.
[0004]
In order to simplify the assembly work and removal work of the above-mentioned formwork, a tunnel construction method using a flexible sheet material instead of the formwork has been proposed (Japanese Patent Laid-Open No. 8-135384).
[0005]
In this method, a sheet material made of a flexible material is placed on a foundation made of slab concrete, both sides of the sheet material are hermetically fixed to the slab concrete, the opening is sealed, and air is injected into the interior. By doing so, it expands into the shape of a tunnel and sprays ready-mixed concrete on its outer peripheral surface to form a tunnel wall.
[0006]
[Problems to be solved by the invention]
However, in such a tunnel construction method, both side edges of the sheet material are fixed to the slab concrete in an airtight state, so it is not easy to maintain the airtightness, and it takes time and labor to complete the airtightness. In addition, there is a problem that it causes an increase in construction costs.
[0007]
An object of the present invention is to propose a method for constructing an underground hollow structure that facilitates construction of the underground hollow structure, can shorten the construction period, and can reduce the construction cost.
[0008]
Another object of the present invention is to propose a cylindrical bag body for building an underground hollow structure that can be suitably used in the above construction method and can facilitate the construction of the underground hollow structure. is there.
[0009]
[Means for Solving the Problems]
In the underground hollow structure construction method of the present invention that solves the above problems, slab concrete is placed at the bottom of the long groove, and a recess is formed along the longitudinal direction at the center of the width of the long groove on the slab concrete. A cylindrical bag body that can be expanded and contracted is placed in the concave portion, and the cylindrical bag body is filled with a pressure fluid and expanded to expand the outer peripheral surface of the cylindrical portion of the cylindrical bag body. A shape corresponding to the inner wall surface of the object, and a space between the outer peripheral surface of the cylindrical portion and the side surface of the long groove by arranging a reinforcing frame and a partition frame that intersects the longitudinal direction of the cylindrical portion of the cylindrical bag body. And constructing a part of the hollow structure by placing and hardening the upper concrete in this space, and after constructing the hollow structure, the tubular bag body is contracted to at least the tubular part The slab so that the end of the slab remains in the inner wall surface of the hollow structure. When moving to an arbitrary position in the longitudinal direction on the core, a liquid is injected into the concave portion and moved in a state where buoyancy is applied to the cylindrical bag body, and a long hollow structure is obtained by repeating the above steps. The gist is to construct.
[0010]
Here, during the movement of the cylindrical bag body, the cylindrical bag body is filled with gas to expand the outer peripheral surface of the cylindrical portion to the inner wall surface of the hollow structure, and the existing continuous structure is connected to the hollow structure. A pressing bag body that can be inflated and contracted is arranged in the inner wall surface of the hollow structure, and the pressing bag body is filled with gas, and the outer peripheral surface is pressed against the inner wall surface and closed between the cylindrical bag body. The cylindrical bag is moved by the internal pressure of the closed space by defining a space and supplying compressed air to the closed space. The friction force between the pressing bag and the inner wall surface of the existing hollow structure is 1.1 times or more than the friction force between the cylindrical bag body and the inner wall surface of the hollow structure. It is a summary.
[0011]
According to the present invention, an outer periphery of the cylindrical portion of the cylindrical bag body is formed by placing a cylindrical bag body that can be expanded and contracted on the slab concrete, filling the cylindrical bag body with a pressure fluid, and expanding it. Since the upper concrete can be cast simply by making the surface shape corresponding to the inner wall surface of the underground hollow structure, there is no need to use the mold for forming the inner wall, and the labor for installing the mold can be saved. it can. Further, if the cylindrical bag body is contracted, it can be easily removed from the hollow structure, so there is no need to remove the mold on the inner wall surface. Therefore, the underground hollow structure can be easily constructed.
[0012]
Further, according to the present invention, after constructing a part of the hollow structure, the cylindrical bag body is shrunk so that the end of the cylinder part remains in the inner wall surface of the hollow structure. Since the process of moving to a different direction and constructing a part of the next hollow structure is repeated in sequence, the formwork for forming the inner wall surface of the hollow structure is not used, so the labor of installing and removing the formwork is repeated. Therefore, a long hollow structure can be easily constructed. Moreover, the cylindrical bag body only repeats contraction, movement, and expansion, and one cylindrical bag body can be used repeatedly.
[0013]
Furthermore, the underground bag structure for building an underground hollow structure according to the present invention is a hollow cylindrical bag body that is hermetically molded from a material made of a rubber-like elastic body and has mirror portions at both ends. An air supply pipe having at least two or more openable and closable fluid supply / exhaust ports in the section, and connected to the fluid supply / exhaust port and having a float at the terminal, and the other fluid supply / exhaust ports The gist is that the liquid feeding pipe connected to the container is accommodated.
[0014]
According to this tubular bag body for constructing an underground hollow structure, the bag body is airtightly formed of a material made of a rubber-like elastic body, and at least two or more openable fluid supply / discharge ports are provided on the mirror surface. Since the air inside the bag body is discharged from at least one fluid supply / exhaust port and the pressure fluid is introduced from the other fluid supply / exhaust port, the bag body is filled with the pressure fluid and the outer peripheral surface of the cylinder portion Can be inflated. Therefore, in the state which expanded the outer peripheral surface of the cylinder part, concrete can be poured and hardened to an outer peripheral surface, and the inner wall surface of a hollow structure can be constructed | assembled. In addition, if air is introduced from the fluid supply / exhaust port and the internal fluid is discharged from the other fluid supply / exhaust port, the outer peripheral surface of the cylindrical portion can be contracted, and the hollow structure can be contracted in the contracted state. It is possible to easily move the cylindrical bag body.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0016]
FIG. 1 is a half sectional view of a bag body 1 showing an embodiment of the underground hollow structure building bag body of the present invention.
[0017]
The underground hollow structure building bag 1 is integrally formed of a rubber-like elastic body reinforced with fibers, and has a cylindrical tube portion 2 having a substantially constant cross-sectional shape in the axial direction, and both end sides thereof. It has a mirror part 3 and is formed in an airtight manner as a whole, and is configured to expand and contract due to fluctuations in internal pressure by injection and discharge of a pressure fluid or the like.
[0018]
As shown in FIG. 2, the mirror part 3 is provided with a fluid supply / exhaust part 8, and the fluid supply / exhaust part 8 includes a water supply / supply valve 4 including a coupling, a ball valve, and the like. A valve 5, a drain valve 6, and an auxiliary valve 7 for pressure measurement are provided. Further, the fluid supply / discharge port portion 8 is provided with a flange portion 10 to which a tensioner 9 can be attached.
[0019]
On the other hand, inside the bag body 1, one terminal 11 a is connected to the air supply / exhaust valve 5, the other terminal 11 b is joined to the float 12, and one terminal 13 a is joined to the drain valve 6. The liquid feeding pipe 13 is accommodated.
[0020]
In such a bag body 1, water is discharged from the water supply / air supply path 14 to the water supply / air supply valve 4 while discharging the internal air from the air supply / exhaust valve 5 with the drain valve 6 closed and the air supply / exhaust valve 5 opened. By introducing a pressurized fluid that has been pressurized, etc., and closing the supply / exhaust valve 5 in a full state, the pressure fluid can be filled into the bag body 1. Since the bag body 1 is composed of a rubber-like elastic body, by filling the pressure fluid, the outer peripheral surface 1a of the bag body 1 can be expanded to form the outer peripheral surface 1a having a desired diameter. The bag body 1 can be weighted.
[0021]
Since the float 12 is attached to the air supply pipe 11 when the pressure fluid is introduced, when the liquid level of the pressure fluid rises, the float 12 floats on the liquid surface of the pressure fluid, and the terminal 11b of the air supply pipe 11 always has the liquid level. Maintained in a higher position. Therefore, it is possible to fill the pressure fluid while discharging the air inside until the inside is full. In addition, since the outer peripheral surface 1a of the bag body 1 is cylindrical, the upper and lower surfaces are not specified at the time of placement, but the float 12 is lifted and sent regardless of which position of the outer peripheral surface 1a is placed downward. The terminal 11b of the trachea 11 is maintained at a position higher than the liquid level.
[0022]
On the other hand, in order to release the internal pressure fluid, the water supply / exhaust valve 4 can be opened by opening the drain valve 6 with the air supply / exhaust valve 5 open, or by closing the air supply / exhaust valve 5 and opening the drain valve 6. By introducing more compressed air, the internal pressure fluid can be discharged from the liquid supply pipe 13. At this time, since the terminal 13b of the liquid feeding pipe 13 is always arranged at the bottom inside the bag body 1 due to gravity, it is possible to discharge substantially the entire amount of fluid inside the bag body 1.
[0023]
Thus, the outer peripheral surface 1a of the bag body 1 can be contracted by releasing the internal pressure fluid, and the weight of the bag body 1 can be reduced by replacing the pressure fluid with air.
[0024]
Next, a reference example of the construction method of the underground hollow structure using the bag body 1 as described above will be described. In this reference example, an underground hollow structure whose overall length is shorter than the overall length of the bag body is constructed.
[0025]
First, as shown in FIG. 3 and FIG. 4, a groove 21 having a length at least twice as long as the bag body 1 is excavated in the ground 20, and slab concrete 22 is formed on the bottom 21 a of the groove 21 with a predetermined thickness. A mold 23 for forming a side wall surface of the hollow structure is placed in the groove wall 21b. And the said bag body 1 is mounted on the slab concrete 22, and the pressurized pressure fluid, such as water, is filled and expanded in the bag body 1, and the outer peripheral surface 1a of the cylinder part 2 of the bag body 1 is made. A shape corresponding to the inner wall surface of the hollow structure is made and the weight is increased.
[0026]
Next, a partition frame 24 is installed between the outer peripheral surface 1a of the cylindrical portion 2 and the mold frame 23 in a direction crossing the longitudinal direction of the cylindrical portion of the cylindrical bag body so as to obtain a desired hollow structure. further, placing the reinforcing rebar 25 in a direction crossing the longitudinal direction and therewith along the outer peripheral surface 1a of the cylindrical portion 2. Then, the hollow concrete 27 is constructed by placing and curing the upper concrete 19 in a space surrounded by the mold 23, the outer peripheral surface 1 a of the cylindrical portion 2, and the partition frame 24.
[0027]
When placing the upper concrete, the buoyancy acts on the bag body 1 because the specific gravity of the upper concrete 19 is large. Even if the weight is increased by using a liquid such as water as the pressure fluid, the bag body 1 may float when it is placed at once. Therefore, it is preferable that the upper concrete 19 is placed in a plurality of times and hardened in such an amount that the bag body 1 does not float.
[0028]
Here, the amount that does not allow the bag body 1 to float is, for example, the weight of the concrete corresponding to the volume of the bag body 1 immersed in the uncured upper concrete 19 at the time of placing the upper concrete 19 once. The amount is in a range smaller than the weight of the bag body 1. In this embodiment, the upper concrete 19 is placed in three divided portions like the liquid surfaces 19a, 19b, and 19c.
[0029]
After the upper concrete 19 is hardened, the pressure fluid in the bag body 1 is discharged as described above, so that the outer peripheral surface 1a of the cylindrical portion 2 is contracted to form a gap between the inner wall of the hollow structure 27 and the pressure. Replace the fluid with air to reduce weight. Then, a tensioning tool 9 is attached to the fluid supply / discharge port 8 of the mirror part 3, the bag body 1 is pulled with a winch or the like using the hole 9a, and the bag body 1 is pulled out from the inside of the inner wall surface 27a of the hollow structure 27. To remove. Then, if necessary, it is backfilled with excavated soil, and an underground hollow structure is constructed.
[0030]
When the hollow structure 27 is constructed in this way, the bag body 1 can be formed into a shape corresponding to the inner wall surface 27a of the hollow structure 27 simply by filling the bag 1 with a pressure fluid such as water and expanding the bag. Therefore, it is not necessary to use a mold for forming the inner wall surface 27a, and the labor for installing the mold can be saved.
[0031]
Further, after the hollow structure 27 is constructed, the outer shape can be contracted and the weight can be reduced by simply discharging the pressure fluid inside the bag body 1. The hollow structure 27 can be removed by moving from the inner side of the inner wall surface 27a. Therefore, there is no need for troubles such as removing the formwork.
[0032]
Furthermore, the bag body 1 pulled out from the inner wall surface 27a of the hollow structure 27 is merely shrunk and can be used repeatedly.
[0033]
Therefore, it is possible to reduce the construction period and construction cost for constructing the hollow structure 27.
[0034]
Next, 1st Embodiment which constructs a culvert by the construction method of the underground hollow structure of this invention is described.
[0035]
In order to construct a culvert longer than the hollow structure 27, as shown in FIG. 5, first, the ground 20 is excavated to form a long groove 28 having a longer distance than the above embodiment, and a slab is formed at the bottom 28a of the long groove. Concrete 22 is placed.
[0036]
And like the said embodiment, the bag body 1 is mounted in the position of A in FIG. 5, is filled with pressure fluids, such as water, is expanded, and the outer peripheral surface 1a and the long groove of the cylinder part 2 of the bag body 1 are expanded. 28, a reinforcing frame 25 and a partition frame 24a crossing the longitudinal direction of the cylindrical portion of the cylindrical bag body are installed, and the upper concrete 19 is placed and cured to construct a part 30a of the underdrain.
[0037]
Next, the partition frame 24a is removed, the pressure fluid of the bag body 1 is released, the cylinder portion 2 is contracted and the weight is reduced, and the bag body 1 is moved to the position B in FIG. Let At this position, the end 2a of the cylindrical portion 2 of the bag body 1 remains in the inner wall surface 30w of the part 30a of the existing culvert.
[0038]
At this position B, again, the bag body 1 is inflated again, the partition frame 24b is disposed on one side and the reinforcing reinforcing bars 25 are disposed, and the end face 30e of the existing culvert part 30a and the partition frame 24b are disposed. Then, in the space surrounded by the outer peripheral surface 1a of the cylindrical portion 2 and the mold 23 on the side surface, the upper concrete 19 is placed in a plurality of times and hardened to construct a part 30b of the next underdrain. This culvert part 30b is continuous with the existing culvert part 30a.
[0039]
And after discharging the pressure fluid of the bag body 1 after repeating such a process, the bag body 1 is sequentially moved to the next position C and subsequent positions, and a long underdrain is easily constructed. Can do.
[0040]
When a long culvert is constructed in this way, the formwork for forming the inner wall surface, which was conventionally required every time a part of the culvert was constructed, is no longer necessary. Can be greatly reduced in the construction of the entire underdrain. Moreover, since the bag body 1 is used after being expanded and contracted by filling and releasing the pressure fluid, it can be used repeatedly easily. Therefore, it is possible to significantly reduce the construction period and construction cost for building the underdrain.
[0041]
In the construction of the underdrain, as shown in FIG. 6, a recess 31 is formed along the longitudinal direction at the center of the width of the long groove 28 on the slab concrete 22, and the bag body 1 is placed in the recess 31. It may be placed to form part of the underdrain. Although this recessed part 31 is not specifically limited, It is preferable to set it as the cross-sectional shape of the curvature substantially larger than the curvature of the cylinder part 2 of the state which expanded the bag body 1 or larger than the curvature of the cylinder part 2. FIG.
[0042]
When the recess 31 is formed in this way, when the bag body 1 is moved after constructing a part of the underdrain, a dam or the like is formed in the recess 31 to inject a liquid such as water into the bag body 1. Buoyancy can be given, and the frictional force between the bag 1 and the slab concrete 22 can be significantly reduced. Therefore, the bag body 1 can be easily moved with a small force, and wear of the outer surface 1a of the bag body 1 at the time of movement can be reduced. Moreover, since the bag body 1 is guided and moved by the recessed part 31 at the time of a movement, when mounting the bag body 1 on the slab concrete 22 after a movement, it is hard to produce position shift and the axial center of the inner wall surface of a culvert shifts. There is nothing.
[0043]
Further, when the bag body 1 is moved, as shown in FIG. 7A, the bag body 1 may be moved by air pressure using a pressing bag body 33 that can expand and contract.
[0044]
In order to move by air pressure, first, after releasing the pressure fluid inside the bag body 1, the compressed air is injected, and the bag is placed so that the outer peripheral surface 1 a of the cylindrical portion 2 contacts the inner wall surface 30 w of the part 30 b of the underdrain. The body 1 is inflated. Then, a pressing bag body 33 provided with a compressed air introduction pipe 32 is arranged inside the inner wall surface 30w of a part 30a of an existing culvert, and the pressing bag body 33 is inflated so that the bag body 1 A closed space 34 is defined between them. At this time, the bag body 1 and the pressing bag body 33 are not necessarily in close contact with the inner wall surface 30w of the culvert, and the air amount supplied from the introduction pipe 32 to the closed space 34 leaks from the gap. What is necessary is just to have the airtightness of the grade which becomes more.
[0045]
Then, by supplying pressurized air from the introduction pipe 32 to the closed space 34, the internal pressure of the closed space 34 is increased, and the bag body 1 is moved by the pressure. In addition, after the movement, the compressed air inside the pressing bag 33 is discharged and repeatedly used.
[0046]
In this way, when the bag body 1 is moved by air pressure, the air pressure in the closed space 34 is uniformly applied to the entire mirror surface 3, and the bag body 1 is moved in the same shape as the inner wall surface of the culvert. It can be moved smoothly, and the bag body 1 can be moved easily.
[0047]
At the time of this movement, the frictional force with the inner wall surface 30w of the pressing bag 33 needs to be larger than the frictional force between the outer peripheral surface 1a of the cylindrical portion 2 of the bag body 1 and the inner wall surface 30w. The internal pressure of 33 needs to be higher than the internal pressure of the bag body 1. Preferably, the frictional force with the inner wall surface 30w of the pressing bag 33 is preferably 1.1 times or more the frictional force between the outer peripheral surface 1a of the cylindrical portion 2 of the bag body 1 and the inner wall surface 30w. . The moving speed of the bag body 1 can be adjusted by adjusting the valve 32b of the introduction pipe 32.
[0048]
In FIG. 7A, the introduction tube 32 penetrates through the central portion of the pressing bag 33 and is airtightly fixed to the mirror portion 3. However, as shown in FIG. You may air-tightly arrange | position between the outer peripheral surface of the body 33, and the inner wall surface 30w.
[0049]
【The invention's effect】
Since the present invention is configured as described above, the following excellent effects can be obtained.
[0051]
According to the underground hollow structure construction method of the present invention, the slab concrete is cast at the bottom of the long groove, and a concave portion is formed along the longitudinal direction at the center of the width of the long groove on the slab concrete. A cylindrical bag body that can be inflated and shrunk is placed on the cylindrical bag body, and the cylindrical bag body is filled with a pressure fluid and inflated so that the outer peripheral surface of the cylindrical portion of the cylindrical bag body is inside the hollow underground structure. While forming a shape corresponding to the wall surface, a reinforcing frame and a partition frame that intersects the longitudinal direction of the cylindrical portion of the cylindrical bag body are arranged between the outer peripheral surface of the cylindrical portion and the side surface of the long groove to constitute a space. In this space, a part of the hollow structure is constructed by placing and hardening the upper concrete, and after constructing the hollow structure, the tubular bag body is contracted to at least the end of the tubular part The slab concrete so that it remains in the inner wall surface of the hollow structure When moving to an arbitrary position in the longitudinal direction, a liquid is injected into the recess and moved in a state where buoyancy is applied to the cylindrical bag, and a long hollow structure is constructed by repeating the above steps. Therefore, it is possible to easily construct a long hollow structure, save the trouble of repeatedly installing and removing the formwork for forming the inner wall surface, and reduce the construction period and cost of constructing a long underground structure I can do it.
[0052]
According to the underground hollow structure building bag of the present invention, the bag is a hollow cylindrical bag that is hermetically molded from a material made of a rubber-like elastic body and has mirror portions at both ends. Provided with at least two or more openable and closable fluid supply / exhaust ports, connected to the fluid supply / exhaust port connected to the fluid supply / exhaust port and connected to the air supply pipe and other fluid supply / exhaust ports in the terminal Since the pipe is filled with pressure fluid, the outer peripheral surface of the cylinder portion can be expanded and the pressure fluid can be discharged and contracted. It can be used suitably for the construction method of a structure.
[Brief description of the drawings]
FIG. 1 is a half sectional view showing an embodiment of a bag body for building an underground hollow structure according to the present invention.
2 is a front view of a fluid supply / discharge port portion of the underground hollow structure building bag of FIG. 1; FIG.
FIG. 3 is a cross-sectional view inside a groove for explaining a reference example of a method for constructing an underground hollow structure according to the present invention.
FIG. 4 is an axial cross-sectional view of the inside of a groove for explaining an embodiment of a method for constructing an underground hollow structure according to a reference example of the present invention.
FIG. 5 is an axial sectional view inside a long groove for explaining an embodiment of the construction method of the underground hollow structure according to the first embodiment of the present invention.
FIG. 6 is a cross-sectional view of the interior of the long groove, showing a method for moving the underground hollow structure building bag.
FIGS. 7A and 7B are views showing a method of moving the underground hollow structure building bag and are axial cross-sectional views inside the long groove. FIGS.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Bag body 1a Outer peripheral surface 2 Cylinder part 2a End part 3 Mirror part 4 Water supply / air supply valve 5 Air supply / exhaust valve 6 Drain valve 7 Auxiliary valve 8 Fluid supply / exhaust part 9 Pulling tool 9a Hole 10 Flange part 11 Air supply pipe 11a, 11b Terminal 12 Float 13 Liquid supply pipe 13a, 13b Terminal 14 Water supply / air supply path 19 Upper concrete 19a, 19b, 19c Liquid level 20 Ground 21 Groove 21a Bottom 21b Groove wall 22 Slab concrete 23 Mold frame 24, 24a, 24b Partition frame 25 Reinforcement Reinforcing bar 27 Hollow structure 27a Inner wall 28 Long groove 28a Bottom 28b Groove wall 30a, 30b Part of underdrain 30e End face 30w Inner wall 31 Recess 31a Edge 32 Introducing pipe 32b Valve 33 Pressing bag 34 Closing space

Claims (4)

In a method for constructing a hollow structure by excavating a long groove for constructing a hollow structure in the ground, placing concrete in the long groove and hardening it,
Placing slab concrete at the bottom of the long groove, forming a recess along the longitudinal direction at the center of the width of the long groove on the slab concrete , and placing a tubular bag body that can expand and contract in the recess, The cylindrical bag body is filled with a pressure fluid and inflated so that the outer peripheral surface of the cylindrical portion of the cylindrical bag body corresponds to the inner wall surface of the underground hollow structure, and the outer peripheral surface of the cylindrical portion Between the side surface of the long groove, a reinforcing frame and a partition frame that intersects the longitudinal direction of the cylindrical portion of the cylindrical bag body are arranged to form a space, and the upper concrete is placed and cured in this space. To construct a part of the hollow structure , and after constructing the hollow structure, the tubular bag body is contracted so that at least the end of the tubular part remains in the inner wall surface of the hollow structure. when Before moving to any position in the longitudinal direction on the concrete slab, By injecting a liquid into serial recess is moved in a state that gave buoyancy tubular type bag, how to build an underground hollow structure to build a hollow structure elongated by repeating the above steps. An existing hollow structure that is continuous with the hollow structure by filling the tubular bag with gas and expanding the outer peripheral surface of the cylinder to the inner wall surface of the hollow structure when the cylindrical bag is moved. An inflatable and compressible pressing bag body is disposed in the inner wall surface, and a gas is filled in the pressing bag body so that the outer peripheral surface is pressed against the inner wall surface to define a closed space between the inner bag and the cylindrical bag body. The method for constructing an underground hollow structure according to claim 1 , wherein the tubular bag body is moved by the internal pressure of the closed space by forming and supplying compressed air to the closed space. Frictional force between the inner wall surface of the pressing bag and the existing hollow structures, is 1.1 times the frictional force between the inner wall surface of the tubular bag and the hollow structure to claim 2 The construction method of the underground hollow structure as described . A hollow cylindrical bag body that is hermetically molded by a material made of a rubber-like elastic body and has mirror portions at both ends, the mirror portion having at least two fluid opening / closing ports that can be opened and closed, A cylinder for construction of a hollow underground structure in which an air supply pipe connected to the fluid supply / exhaust port and having a float at a terminal and a liquid supply pipe connected to another fluid supply / exhaust port are accommodated inside a cylindrical bag body Mold bag body.

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