JPH07102878A - Construction method of underground structure - Google Patents

Abstract

PURPOSE:To prevent the invasion of a mortar placed in framworks into an excavator from the front end surface of the excavator. CONSTITUTION:After preventing the invasion of a mortar into an excavator from the front end surface of the excavator by covering the front surface of the excavator 30 liquidtight by a mortar blocking member 49, the mortar is placed in framworks 51 and 92. And by holding the second members 46 and 86 to the side wall 36 of a shaft 34 through a coagulated mortar, the watertightness around pipes 10 and 12 following the rear side of the excavator is maintained by the second members and the coagulated mortar.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention arranges a plurality of pipes having at least one engaging portion horizontally by a pipe propulsion method so that the engaging portions of adjacent pipes engage with each other. The present invention relates to a method of constructing an underground structure such as an inner wall, a reinforcement body, and a water stop body.

[0002]

2. Description of the Related Art A pipe used in a so-called pipe roof construction method for constructing an underground structure by a pipe propulsion method generally has at least one pipe arranged on an outer peripheral surface of a tubular main body so as to extend in a longitudinal direction of the main body. One engaging portion is provided, and the engaging portions of adjacent pipes are horizontally arranged so as to engage with each other.

When placing these pipes underground, it is necessary to prevent groundwater from flowing around the pipes to the starting shaft. Therefore, conventionally, a hole having a shape corresponding to the cross-sectional shape of the pipe is formed in the rubber plate, the rubber plate is attached to the side wall of the starting shaft, and the shield tunnel excavator and the pipe are grounded through the hole. The method of pushing into is adopted.

However, since the cross-sectional shape of the pipe used in the pipe roof construction method is complicated, it is necessary to form a hole in the rubber plate having a shape that reliably maintains the liquid tightness between the pipe and the side wall of the starting shaft. Is difficult For this reason, conventionally, the water blocking agent had to be injected over the entire length region in which the pipe was arranged.

In order to solve the above-mentioned problems, the outer peripheral surface of the shield tunnel excavator having a cross section having a size substantially the same as the cross section of the main body of the pipe has a size substantially the same as the size of the cross section of the engaging part of the pipe. A first member having a cross section of a height corresponding to the position of the engaging portion on the outer peripheral surface of the main body portion, and after or prior to this, the excavator is arranged in a starting shaft, After or prior to this, an elastically deformable second member is arranged around the assembly of the excavator and the first member, a formwork is arranged around the second member and the mortar is The second member is cast into a formwork and carried on the side wall of the shaft through the cured mortar, whereby the watertightness or the liquidtightness around the pipe following the rear part of the excavator is improved. Proposal of a method to maintain the material and the set mortar The (JP-A-4-38397).

However, since the excavator usually has a structure in which the excavated material is received from the front end face into the excavator, in the above method, the mortar cast in the formwork enters the excavator from the front end face of the excavator. It enters and condenses in the excavator.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to prevent mortar cast in a mold from entering the excavator from the front end face of the excavator.

[0008]

SOLUTION: The construction method of the present invention is a shield tunnel excavator having a cross section having a size substantially the same as the size of the cross section of the main part of a pipe, and the outer peripheral surface of the shield engaging part of the pipe. First having a cross section of approximately the same size as the cross section
The shield type tunnel excavator in which the member of FIG. 2 is arranged corresponding to the position of the engaging portion on the outer peripheral surface of the main body portion is arranged in the starting shaft, and after this or before this, the elastically deformable second A member is disposed around the assembly of the excavator and the first member, and the front surface of the excavator is covered with a mortar blocking member that blocks passage of mortar, and the formwork is wrapped around the second member. Arranged, mortar is cast in the mold, and the second member is carried on the side wall of the shaft through the mortar condensed, and the excavator is advanced while excavating the ground by the excavator. At the same time, it includes advancing the pipe following the rear of the excavator to place the pipe underground.

In the present invention, the second member has a hole having a shape corresponding to the cross-sectional shape of the pipe when the second member is maintained in the solidified mortar, and the outer periphery of the excavator and the first member. Pressed on the surface. Thus, when the pipe is inserted into the hole formed in the second member, the second member is pressed against the outer peripheral surface of the pipe by its own restoring force, so that the liquid between the pipe and the side wall of the vertical shaft is The tightness is reliably maintained by the second member and the set mortar.

The mortar blocking member such as a sheet-like member is torn to a small extent due to the excavating force of the excavator, the frictional force between the excavator and the cutting face, etc. when the excavator is advanced, and the mortar blocking member inside the excavator together with the excavation product. Is taken into.

According to the present invention, after the front surface of the excavator is covered with the mortar blocking member, the mortar is placed in the mold, so that the mortar placed in the form is excavated from the front end surface of the excavator. There is no danger of getting inside the aircraft.

A region extending from the front surface to the outer periphery of the front end of the excavator is covered with the mortar blocking member, and the mortar blocking member is liquid-tightly attached to the outer periphery of the front end of the excavator by a deformable elongated member. Preferably. Thereby, the front surface of the excavator can be closed easily and reliably.

A region extending from the front surface to the front end outer circumference of the excavator to the front end outer circumference of the second member is covered with the mortar blocking member, and the mortar blocking member is at least a deformable elongated member. It is preferable to mount the second member in a liquid-tight manner on the outer periphery of the front end portion. As a result, the mortar blocking member is destroyed along with the advance of the excavator and is taken into the excavator together with the excavated material.

Further, prior to disposing the excavator in the shaft, a hole for advancing the excavator is formed in the side wall of the shaft, and the formwork is arranged around the second member before the excavator is arranged. Preferably including the front end of the. This allows the excavator to move forward immediately after the mortar has set.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, referring to FIG. 1, the first embodiment used in the present invention
And an example of the second tubes 10 and 12 will be described.

In FIG. 1, the first tube 10 has a cylindrical main body portion 14 and a C-shaped cross-sectional shape and has a main body portion 14.
And a pair of C-shaped engaging portions 16 extending in the longitudinal direction of the main body portion 14.

Both C-shaped engaging portions 16 have the same length as the main body portion 14, and the main body portion is arranged so that the gap 18 between the C-shaped engagement portions 16 is radially outward of the main body portion 14. It is welded to 14. Each gap 18 continuously extends from one end to the other end of the corresponding C-shaped engaging portion 16.

On the other hand, the second pipe 12 has a cylindrical main body 20 and a C-shaped member having a C-shaped cross-section and having an outer peripheral surface of the main body 20 extending in the longitudinal direction of the main body 20. Joint part 22
And a T-shaped engaging portion 24 having a T-shaped cross-sectional shape capable of engaging with the C-shaped engaging portions 16 and 22.

The C-shaped engaging portion 22 has almost the same length as the main body portion 20, and the main body portion is arranged so that the gap 26 of the C-shaped engaging portion 22 is located radially outward of the main body portion 20. It is welded to 20. Each gap 26 also extends continuously from one end to the other end of the corresponding C-shaped engaging portion 22. T-type engaging portion 24
Has substantially the same length as the main body portion 20 and is welded to the main body portion 20.

Each of the first and second tubes 10 and 12 is divided into a plurality of short tube units having the same sectional shape and size. The short pipe units are connected to each other by bolts, welding or the like when laid by the pipe propulsion method.

Next, an embodiment of the pipe roof construction method using the first and second pipes 10 and 12 will be described with reference to FIGS.

Laying the first tube 10

A1) First, as shown in FIGS. 2 and 3, the first pipe 10 and the shield tunnel excavator 30.
A hole 32 is formed in the side wall 36 of the starting shaft 34 for starting the vehicle.

The hole 32 has a cross-sectional shape that is substantially the same as the cross-sectional shape of the first pipe 10 and allows the passage of the first pipe 10 and the shield tunnel excavator 30. It is slightly larger than the size of the cross section. The earth and sand 38 around the starting shaft 34 has been subjected to a water stop treatment in which a water stop agent is injected in advance. The water stop process is performed at least over the range of the length of the excavator 30.

The excavator 30 is, for example, Japanese Patent Publication No. 4-6971.
It is a known device used in the pipe propulsion method, as described in Japanese Patent Publication No. 9 and the like. This excavator 30 includes a first shield body 30 in which a cutter assembly for excavation is arranged.
a and a second shield body 30b connected to the rear portion of the first shield body. The excavator 30 is mounted on the starting shaft 34 by the original pushing device, and the rail assembly 4 is installed.
0 is advanced in a substantially horizontal direction, and the tip portion of the first shield body 30a is arranged to be received in the hole 32.

A2) Maintaining liquid tightness between the first tube 10 and the side wall 36, as shown in FIGS. 4 and 5, in parallel with the above steps, and preferably prior to the above steps. A pair of rod-shaped first members 44 used for forming the sealing means 42 (see FIGS. 6 and 7) are provided on the outer peripheral surface of the excavator 30 and at the outer peripheral surface of the main body portion 12 of the first pipe 10.
It is arranged corresponding to the position of the mold engaging portion 16.

Both first members 44 have a circular cross-sectional shape with a diameter substantially the same as the diameter of the C-shaped engaging portion 16 of the first tube 10, and the rear end of the first shield body 30a. Section to the front end of the second shield body 30b from the excavator 3
0 so as to extend in the longitudinal direction by adhesion or the like.
It is attached to the outer peripheral surface of 0. As a result, the excavator 30
The cross-sectional shape of the assembly in which the first tube 44 and the first member 44 are combined is substantially the same as that of the first tube 10. First member 44
Can be made of styrofoam, for example.

A3) After the step A2, as shown in FIGS. 6 and 7, a second elastically deformable second member like rubber.
Members 46 are disposed around the assembly of excavator 30 and both first members 44.

The second member 46 has a long plate-like main body portion 46a having a width dimension substantially the same as the length dimension of the first member 44.
And a plurality of rib-shaped protrusions 46b formed on one side of the main body portion at intervals in the width direction of the main body portion. In this case, for example, after the excavator 30 and the both first members 44 are arranged as shown, the second member 46 is arranged.
Can be placed.

However, a second member having a tubular main body and a plurality of rib-shaped projections formed on the outer peripheral surface of the main body at intervals in the axial direction may be used. In this case, for example, the excavator 30 may be arranged as illustrated while the first and second members 44 and 46 are arranged in advance in the excavator 30.

The second member 46 comprises a plurality of bands 48 and a plurality of fasteners 50 interconnecting the bands,
It is fastened to the assembly of the excavator 30 and the first member 44, and also includes first and second shield bodies 30a, 30.
It is arranged so as to extend over b, that is, so as to close the connecting portion of the first and second shield bodies 30a and 30b with the main body portion, and covers the entire longitudinal direction of the first member 44.

A4) After the step A3, as shown in FIG. 6, the mortar blocking member 49 for blocking the passage of the mortar is provided from the front surface of the excavator 30 to the outer peripheral surface of the front end of the excavator 30, that is, the first shield body. Second through the outer peripheral surface of 30a
Is disposed so as to cover the outer periphery of the front end portion of the member 46 in a liquid-tight manner. The mortar blocking member 49 keeps the mortar cast until the mortar cast therein solidifies as will be described later.
It is a member that prevents the material from getting into the inside of 0, and for example, a sheet-shaped member such as a vinyl sheet, oil paper, pressure paper, plain paper, non-woven fabric, or woven fabric can be used.

The mortar blocking member 49 may be formed in advance into a bag shape or a cap shape with a material that blocks the passage of mortar, for example, an impermeable material. However, the sheet-shaped member is moved from the front surface of the excavator 30 to the second member 4 via the outer peripheral surface of the first shield body 30a.
You may arrange | position so that the area | region which covers the front-end part outer periphery of 6 may be covered liquid-tightly.

The mortar blocking member 49 is attached to the outer peripheral surface of the front end of the excavator 30 and the outer peripheral surface of the front end of the second member 46 by a plurality of deformable elongated members 51. Long member 5
As 1, rubber, a cord, a wire, a wire, a belt or the like can be used.

A5) After completing the above steps A1 to A4, the mold 52 and the plurality of anchors 54 are arranged around the second member 46, as shown in FIGS. 6 and 7.

The mold 52 includes a bottom plate portion 52a, a pair of side plate portions 52b, and a rear plate portion 52c. Both side plate portions 52b contact the outer peripheral surfaces of the second member 46 and the band 48. The rear plate portion 52c is arranged so as to contact the rear end edge of the second member 46. Therefore, the space formed by the side wall 36 and the mold 52 is the excavator 30, the first and second spaces.
The upper and lower chambers are partitioned by the members 44 and 46 and the band 48.

The anchor 54 is attached to the side wall 36. The anchors 54 arranged above the excavator 30 are connected to each other by a plurality of reinforcing bars 56, and the anchors 54 arranged below are connected to each other by a plurality of other reinforcing bars 56. Each side plate portion 52b also has a plurality of anchors 58 extending inwardly from the side plate portion.

On the rear plate portion 52c of the form 52, the first pipe 1
A hole having substantially the same shape and size as the zero cross section is formed.

A6) Next, as shown in FIGS. 6 and 7, mortar is cast in the space formed by the side wall 36 and the mold 52. The mortar is injected into the upper chamber from above and an injection port 60 formed in the rear plate portion 52c.
Is injected into the lower chamber. Thereby, as shown in FIG. 6, the second member 46 is elastically deformed and pressed against the excavator 30 and the first member 44.

A part of the cast mortar flows out to the space between the hole 32 and the excavator 30 and the second member 46 and to the front of the excavator 30 through the space. However, since the mortar blocking member 49 is arranged so as to liquid-tightly cover the outer circumference of the front end portion of the second member 46 from the front surface of the excavator 30 through the outer peripheral surface of the first shield body 30a, the mortar that has flowed out. Is prevented by the mortar blocking member 49 from flowing into the excavator from the front surface of the excavator 30 and from the connection portion of the first and second shield bodies 30a and 30b.

When the mortar solidifies, the second member 46
Are supported on the side wall 36 via the set mortar 62. The space between the excavator 30 and the sidewall 36 is closed by the second member 46 and the solidified mortar 62. Thereby, the first and second members 44, 46 and the condensed mortar 62 liquid-tightly close the space between the excavator 30 and the side wall 36.

A7) Next, as shown in FIG. 8, after the excavator 30 is advanced by a predetermined distance, the first short pipe unit of the first pipe 10 is connected to the rear end of the excavator 30 by a plurality of bolts. To be done. The first short pipe unit is arranged such that its main body part is aligned with the excavator 30 and the C-shaped engagement part is aligned with the first member 44.

When the excavator 30 is moving forward, the second member 46 is
It is not advanced because it is supported by the side wall 36 through the condensed mortar 62, but due to its own restoring force the excavator 3
Pressed against the outer surface of zero. Also, the mortar blocking member 49
Is fractured as the excavator 30 advances, and is received in the excavator 30 together with the excavated material.

A8) Next, as shown in FIG. 9, the step of advancing the excavator 30 and the first pipe 10 while excavating the earth and sand by the excavator 30, and the short pipe unit next to the rear short pipe unit. And the step of connecting are repeated until the excavator 30 reaches the reaching shaft.

During this time, the first pipe 10 moves inside the second member 46, and the second member 46 is pressed against the outer surface of the first pipe 10 by its own restoring force. The member 46 and the mortar 54 act as a sealing means 42 that liquid-tightly closes the space between the side wall 36 and the first tube 10. Therefore, while the first pipe 10 is being laid, the starting shaft 3
Leakage of groundwater to 4 is prevented.

As shown in FIG. 10, the front end of the C-shaped engaging portion 16 of the shortest short tube unit is previously closed by a conical cap 64. Therefore, sediment or groundwater is prevented from entering the C-shaped engaging portion 16 from the foremost end of the C-shaped engaging portion 16 of the shortest pipe unit at the most distal end.

A bag 65 containing a hardening agent such as water glass is arranged at each C-shaped engaging portion of each short tube unit. For this reason, the C-shaped engaging portion 16 is liquid-tightly closed, so that earth and sand or groundwater is prevented from entering the C-shaped engaging portion 16 from the gap 18 of the C-shaped engaging portion 16, and The C-shaped engaging portion 16 is prevented from acting as water.

The first member 44 may or may not be removed prior to carrying out step A8. When the first member 44 is not removed prior to performing step A8,
The first member 44 is broken by earth pressure or the cap 64.

A9) As shown in FIG. 11, when the excavator 30 arrives just before the reaching shaft 66, a hole 70 is formed in the side wall 68 of the reaching shaft 66. The hole 70 has substantially the same shape and size as the cross section of the first tube 10 to move the excavator 30 into the reaching shaft 66 and receive the tip of the first tube 10.

The earth and sand 72 around the reaching shaft 66 is also water-stopped by injecting a water-stopping agent in advance. The water stop process is performed at least over the range of the length of the excavator 30.

A10) As shown in FIG. 11, the first tube 1
When the tip of 0 reaches the inside of the reaching shaft 66, the first pipe 10
A sealing means 74 is formed which maintains a liquid-tight space between the hole 70 and the hole 70.

The sealing means 74, like the sealing means 42, is an elastically deformable member 7 arranged around the first tube.
6, a plurality of bands (not shown) for attaching the member to the first tube, and fasteners (not shown) for connecting the bands to each other
It can be formed by using the mold frame 78 and the mortar by placing the mortar in the space formed by the side wall 68 and the mold frame 78 and solidifying the mortar. However, the hole 70 may be closed with the solidified mortar by pouring the mortar into the hole 70 and solidifying the mortar.

A11) After that, the excavator 30 is taken out of the reaching shaft and installed again in the starting shaft so that the second pipe 12 is installed next to the installed first pipe.

Laying the second pipe 12

B1) As shown in FIG. 12, first, the form 5
One side plate portion 52b of the two is removed so as to leave the anchor 58 attached to the sealing means 42. As a result, of the first member 46 and the band 48 wound around the first pipe 10, the portion that was in contact with the removed side plate portion and the end surface of the anchor 58 that was provided on the removed side plate portion. And are exposed on the side surface of the sealing means 42.

B2) Next, the exposed portions of the first member 46 and the band 48 are cut off. As a result, the gap 18 of the one C-shaped engaging portion 16 is opened to the side surface of the sealing means 42.

B3) Next, the hole 80 for starting the second pipe 12 and the excavator 30 is formed in the side wall 3 of the starting shaft 34.
6 is formed. The hole 80 has a cross-sectional shape that is substantially the same as the cross-sectional shape of the second pipe 12 excluding the T-shaped engaging portion 24 to allow passage of the second pipe 12 and the excavator 30. It is slightly larger than the cross-sectional size of the tube 10. The excavator 30 is arranged so that its tip is received in the hole 80.

The hole 80 is formed in the T-shaped engaging portion 24 of the second tube 12.
Is in communication with a hole formed in the sidewall 36 for the first tube 10 so that it can engage one C-shaped engagement portion 16 of the first tube 10 as shown in FIG. .

B4) In parallel with the step B3, preferably before the step B3, as shown in FIG. 12, a sealing means 8 for maintaining liquid tightness between the second tube 12 and the side wall 36.
A first member 84 similar to the first member 44 used to form the position of the C-shaped engaging portion 22 on the outer peripheral surface of the main body portion 20 of the second pipe 12 on the outer peripheral surface of the excavator 30. It is arranged corresponding to.

Like the first member 44, the first member 84 has a circular cross-sectional shape having a diameter substantially the same as the diameter of the C-shaped engaging portion 22 of the second pipe 12, and the excavation is performed. It is arranged on the outer peripheral surface of the excavator 30 by adhesion or the like so as to extend in the longitudinal direction of the machine 30. As a result, the cross-sectional shape of the assembly in which the excavator 30 and the first member 84 are combined has a T-shaped engaging portion 2
It is almost the same as that of the second tube 10 except 4.

B5) After the step B4, as shown in FIG. 12, an elastically deformable second member 86 similar to the second member 46 is formed in the assembly of the excavator 30 and the first member 84. It is placed around.

Like the second member 46, the second member 86 includes a plurality of bands 88 and a plurality of stoppers 90 that connect the bands to each other, and thus the excavator 30 and the first member 84.
And tightened to the assembly. Each band 88 is connected to an anchor 58 remaining on the sealing means 42.

B6) After the step B5, as in the case of the first tube 10, the mortar blocking member 49 as shown in FIG.
However, so as to cover the front end outer circumference of the second member 84 from the front surface of the excavator 30 through the front end outer peripheral surface of the excavator 30 in a liquid-tight manner,
It is attached by the long member 51.

B7) Next, as shown in FIG. 12, the mold 92 and the plurality of anchors 94 are arranged around the second member 86.

The mold 92 includes a bottom plate portion 92a and a side plate portion 92.
b and a rear plate portion (not shown), the side plate portion 92b contacts the outer peripheral surfaces of the second member 86 and the band 88, and the rear plate portion has the rear end edge of the second member 86. , So that the sealing means 42 acts as one side plate portion,
Will be placed. Therefore, the space formed by the side wall 36, the sealing means 42, and the mold 92 is divided into upper and lower chambers by the excavator 30, the first and second members 84 and 86, and the band 88.

The anchor 94 is attached to the side wall 36. The anchors 94 arranged above the excavator 30 are connected to each other by a plurality of reinforcing bars 96, and the anchors 94 arranged below are connected to each other by a plurality of other reinforcing bars 96.

The side plate portion 92b also has a plurality of anchors 98 extending inwardly from the side plate portion. The rear plate portion of the mold 92 is formed with a hole having substantially the same shape and size as the cross section of the second tube 12.

B8) Next, as in the step A6, mortar is placed in the space formed by the side wall 36 and the mold 92. The mortar is injected into the upper chamber from above and also into the lower chamber through the inlet formed in the rear plate portion. As a result, as shown in FIG. 12, the second member 86 is elastically deformed and pressed against the excavator 30 and the first member 84.

Also in this case, a part of the cast mortar flows out to the space between the hole 80 and the excavator 30 and the second member 86 and to the front of the excavator 30 through the space.
However, since the mortar blocking member 49 is arranged so as to liquid-tightly cover the outer circumference of the front end portion of the second member 86 from the front surface of the excavator 30 through the outer peripheral surface of the excavator 30, the mortar that has flowed out is discharged. Flowing into the excavator from the front of 30 and from the connection of the first and second shield bodies is
It is prevented by the mortar blocking member 49.

When the mortar solidifies, the second member 86
Is the side wall 36 of the starting shaft through the set mortar 62.
Supported by. The space between the excavator 30 and the side wall 36
It is closed by the second member 86 and the solidified mortar 100. Thereby, the first and second members 84, 8
6 and the solidified mortar 100 liquid-tightly close the space between the excavator 30 and the side wall 36.

B9) Next, as in step A7, after the excavator 30 has been advanced a predetermined distance, the first short pipe unit of the second pipe 12 is connected to the rear end of the excavator 30 by a plurality of bolts. It In the first short pipe unit, the main body part thereof coincides with the excavator 30, and the C-shaped engaging part 26 has the first member 84.
And the T-shaped engaging portion 24 is arranged so as to coincide with the C-shaped engaging portion 16 of the laid first pipe 10.

During the forward movement of the excavator 30, the second member 86 is
It is not advanced because it is supported by the side wall 36 of the starting shaft through the condensed mortar 100, but it is pressed against the outer surface of the excavator 30 by its own restoring force. Further, the mortar blocking member 49 is broken along with the forward movement of the excavator 30 and is received in the excavator 30 together with the excavated material.

B10) Next, as in the step A8 described above, a step of advancing the excavator 30 and the second pipe 12 while excavating the earth and sand by the excavator 30, and the next short pipe to the rear short pipe unit. The process of connecting the units is repeated until the excavator 30 reaches the reaching shaft 66.

During this time, the second tube 12 moves inside the second member 86, and the second member 86 is pressed against the outer surface of the second tube 12 by its own restoring force. This prevents groundwater from leaking to the starting shaft 34 while laying the second pipe 12.

Also when laying the second pipe 12, a cap of the same type as the cap 64 shown in FIG. 10 is arranged at the foremost end of the C-shaped engaging portion of the shortest short pipe unit, and the hardener is also used. A bag enclosing the above is placed in each C-shaped engaging portion of each short tube unit.

When laying the second pipe 12, the T of the second pipe 12 is
As shown in FIG. 13, the die engagement portion 24 is a first laid portion.
Is engaged with the C-shaped engaging portion 16 of the pipe 10 of
The bag arranged in the mold engaging portion 16 is destroyed.

B11) When the excavator 30 arrives just before the arrival shaft, the excavator 30 is moved into the arrival shaft, and the hole for receiving the tip end of the second pipe 12 is formed in the side wall of the arrival shaft, as in step A9. Is formed.

When the tip of the second pipe 12 reaches the inside of the reaching shaft, liquid-tightness is provided between the second pipe 12 and the hole formed on the immediate wall of the reaching shaft, as in the step A10. A sealing means is formed that keeps it in good condition.

B12) Next, in order to lay the next second pipe next to the second pipe 12 laid this time, the excavator 30
Is taken out of the reaching shaft and installed again in the starting shaft.

B13) After that, in order to lay the next second pipe next to the second pipe 12 laid this time, the steps B1 to
B12 is repeated a number of times determined by the number of second tubes to be laid next.

In the above process, the excavator 30 and the first and second pipes can be advanced by the original pushing device using at least one jack.

By performing the above steps,
An underground structure including a plurality of pipes whose engaging portions are engaged with each other is constructed. The sectional shape of the underground structure may be other shapes such as a quadrangle, a circle, a U-shape, a U-shape, a V-shape, an inverted U-shape, and an inverted V-shape.

The angle formed by both C-shaped engaging portions 16 around the axis of the main body portion 14 of the first pipe 10 does not need to be 180 degrees as in the example shown in the figure, and an underground structure to be constructed. The angle can be any angle depending on the cross-sectional shape. Similarly, the angle between the C-shaped engaging portion 22 and the T-shaped engaging portion 24 about the axis of the main body portion 20 of the second pipe 12 is also arbitrary depending on the sectional shape of the underground structure to be constructed. Can be angled

When the connecting portion of the first and second shield main body portions 30a and 30b of the excavator 30 is not located in the space for placing mortar, when the connecting portion is covered with the second member, When the excavator 30 is not divided into the first and second shield body portions 30a and 30b, or when there is no risk of mortar flowing into the excavator from the connecting portion, the mortar blocking member is at least the excavator. It may be arranged so as to cover the front surface of 30.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of first and second pipes used in the present invention.

FIG. 2 is a cross-sectional view showing one step of the present invention.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a cross-sectional view showing another process of the present invention.

5 is a cross-sectional view taken along line 5-5 of FIG.

FIG. 6 is a cross-sectional view showing another process of the present invention.

7 is a cross-sectional view taken along line 7-7 of FIG.

FIG. 8 is a cross-sectional view showing another process of the present invention.

FIG. 9 is a cross-sectional view showing another process of the present invention.

FIG. 10 is a view showing a cap and a bag arranged in a C-shaped engaging portion.

FIG. 11 is a cross-sectional view showing another process of the present invention.

FIG. 12 is a sectional view similar to FIG. 3, showing another step of the present invention.

FIG. 13 is a cross-sectional view showing a state in which a C-shaped engaging portion and a T-shaped engaging portion are engaged with each other.

[Explanation of symbols]

 10 1st pipe 12 2nd pipe 14,20 Main part 16,22 C-type engaging part 24 T-type engaging part 30 Shield type tunnel excavator 32,80 hole 34 Starting shaft 36 Side wall 42,82 Sealing means 44 , 84 First member 46, 86 Second member 49 Mortar blocking member 51 Long member 52, 92 Form 62, 100 Mortar

Claims (4)

[Claims] 1. A plurality of pipes each having a tubular main body and at least one engaging portion on an outer peripheral surface of the main body extending in a longitudinal direction of the main body, wherein an engaging portion of adjacent pipes is provided. In a method of constructing an underground structure by arranging them horizontally by a pipe propulsion method so that they engage with each other, a shield-type tunnel excavator having a cross section of approximately the same size as the cross section of the main body. A shield-type tunnel in which a first member having a cross section that is substantially the same size as the cross section of the engaging portion is arranged on the outer peripheral surface of the lever corresponding to the position of the engaging portion on the outer peripheral surface of the main body. The excavator is disposed in the starting shaft, and after or prior to this, the elastically deformable second member is disposed around the assembly of the excavator and the first member and the front face of the excavator. Prevent the passage of mortar Covering with a mortar blocking member, arranging the mold around the second member, placing the mortar in the mold to support the second member on the side wall of the shaft through the mortar condensed. Constructing an underground structure including advancing the excavator while excavating the ground by the excavator and advancing the pipe following the rear part of the excavator and placing the pipe in the ground Method. 2. A region extending from the front surface to the outer circumference of the front end of the excavator is covered with the mortar blocking member, and the mortar blocking member is a deformable elongated member that is liquid-tight to the outer circumference of the front end of the excavator. The construction method according to claim 1, which is attached to 3. An area extending from the front surface to the outer periphery of the front end portion of the excavator to the outer periphery of the front end portion of the second member is covered with the mortar blocking member, and the mortar blocking member is a deformable elongated member. The construction method according to claim 1, wherein at least the outer periphery of the front end portion of the second member is liquid-tightly mounted. 4. Further, prior to disposing the excavator in the shaft, a hole for advancing the excavator is formed in a side wall of the shaft, and a formwork is arranged around the second member. 4. The construction method according to any one of claims 1 to 3, including inserting a front end portion of an excavator into the hole.