JP2921935B2 - Tunnel formation method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tunnel forming method for freezing a mountain surrounding a tunnel to be constructed and constructing the tunnel.

[Conventional technology]

Conventionally, when a tunnel is constructed in a hydrated ground, as a method of solidifying the ground, a chemical liquid injection method, a cement injection method, a method of freezing the ground using an antifreeze solution (brine), and the like are adopted. Have been.

[Problems to be solved by the invention]

The method of freezing the ground with the antifreeze liquid has a slow thermal response and a low thermal conductivity, so that a period required for the formation of frozen soil is long, and therefore, a preparation period until the start of construction of the tunnel after the formation of the frozen soil becomes long, and Expenses have also increased.

The present invention has been made in view of the above-described circumstances, and allows a wet ground to be excavated or widened to a tunnel to be quickly frozen and excavated or widened quickly, and also to perform cooling efficiently. Is a technical task.

[Means for solving the problem]

The present invention relates to a condensing section 8 and an evaporating section formed on the side wall portion 36 of the shaft 35 where the shielded tunnel excavator 30 starts or reaches, and which becomes the peripheral portion 24 of the tunnel 22 to be excavated.
Between 10, the heat pipe 1 provided with the heat insulating material 4 and the heat insulating portion 9 is inserted, and the condensing portion 8 of the heat pipe 1 is cooled by the refrigerant cooled by the refrigerating device 15, and the heat pipe 1 is cooled. The tunnel forming method is to excavate the tunnel by freezing the ground which is to be the surrounding portion 24 of the tunnel 22 to be excavated in the evaporating section 10.

In addition, it started from both ends of the tunnel 22 to be excavated.
At the joint position of the two shield type tunnel excavators 30,
The heat pipe 1 provided with the heat insulating material 4 and provided with the heat insulating part 9 is inserted between the condenser part 8 and the evaporating part 10 in the ground which becomes the peripheral part 24 of the tunnel 22, and the heat pipe 1 is condensed. The part 8 is cooled by the refrigerant cooled by the refrigerating device 15, and the evaporating part 10 of the heat pipe 1 freezes the ground which is the peripheral part 24 of the tunnel 22 to excavate the tunnel 22.

Further, a peripheral portion 24 of the portion 25 to be widened of the tunnel 22
A heat pipe 1 provided with a heat insulating material 4 and provided with a heat insulating portion 9 is inserted between the condensing portion 8 and the evaporating portion 10 in the ground, and the condensing portion 8 of the heat pipe 1 is cooled by the refrigerating device 15. The tunnel 22 is widened by cooling with a cooled refrigerant and freezing the ground which is to be the peripheral portion 24 of the portion to be widened of the tunnel 22 in the evaporating section 10 of the heat pipe 1.

[Action]

In the present invention, the freezing of the surrounding portion 24 of the tunnel 22 and the surrounding portion 24 of the tunnel 22 to be excavated is cooled by the heat pipe 1 cooled by the refrigerating device 15. Is frozen at a very low temperature and quickly.

And the start of the shield tunnel excavator 30, or
The reaching side wall portion 36 of the shaft 35, the joining position of the two shield tunnel excavators 30, and the peripheral portion 24 of the widened portion 25 of the tunnel 22 can quickly freeze the ground to an extremely low temperature.

Further, since the heat insulating material 4 is attached between the condenser 8 and the evaporator 10 to provide the heat insulating part 9, the heat insulating part 9 does not need to be cooled, for example, as shown in FIGS. The transfer of heat into the heat pipe 1 from the outside between the condensing section 8 and the evaporating section 10 is prevented.

〔Example〕

FIG. 1 shows an embodiment of a freezing apparatus provided with a heat pipe 1 used in the present invention.

Heat pipe 1 provided in the freezing apparatus of this embodiment
Has an airtight container 2 formed of a metal tube, and a capillary structure 3 is stretched on the inner peripheral surface of the airtight container 2. A cooling jacket is provided on the outer periphery of the base of the closed container 2.
17 is detachably mounted, this cooling jacket 17
Is formed such that the refrigerant cooled by the cooling device 15 is injected through the expansion valve 16. Then, the heat pipe 1 where the cooling jacket 17 is mounted becomes the condensing section 8.

Subsequent to the condensing section 8, the closed vessel 2 of the heat pipe 1
A heat insulating portion 9 with a heat insulating material 4 interposed therebetween is provided between the heat pipe 1 and the capillary structure 3. A portion following the heat insulating portion 9 is an evaporating portion 10. , Methane and other working fluids are enclosed.

The heat pipe 1 operates as described below. That is, the refrigerant compressed and cooled by the refrigerating device 15 expands via the expansion valve 16 to a low temperature, and flows into the cooling jacket 17.

Then, the working fluid in the heat pipe 1 in contact with the cooling jacket 17 is cooled, condensed, and condensed.
Is absorbed by the capillary structure 3 of the condenser 8.

Then, the working fluid in the capillary structure 3 of the condenser 8 is
Due to the capillary phenomenon, the heat pipe 1 moves in the capillary structure 3 in the heat pipe 1 and moves into the capillary structure 3 in the evaporating section 10 of the heat pipe 1.

The working fluid in the capillary structure 3 of the evaporator 10 is
The heat pipe 1 absorbs heat from the ground or the like in contact with the evaporating section 10 and evaporates.
Into the condensing section 8, where it is cooled, condensed and again condensed.
Is absorbed by the capillary structure 3.

The heat insulating material 4 of the heat pipe 1 can be mounted outside the closed container 2.

FIG. 2 is a view for explaining an embodiment of a method of excavating the tunnel 22 on the side wall portion 36 of the shaft 35 at which the shield type tunnel excavator according to the present invention starts or reaches.

In this embodiment, the evaporating part 10 of the heat pipe 1 is driven into the side wall part 36 of the shaft 35, which is the surrounding part 24 of the tunnel 22 to be excavated, or the heat pipe insertion hole is formed in the side wall part 36. And the evaporator of the heat pipe 1 is inserted into this hole.
Insert 10

Then, the refrigerant cooled to a low temperature by the refrigerating device 15 is injected into the cooling jacket 17 via the expansion valve 16. Then, the refrigerant cooled to a low temperature by the refrigerating device 15 is supplied to the expansion valve.
By passing through 16 and expanding, the temperature becomes extremely low and the condensing section 8 of the heat pipe 1 is cooled.

Then, the working fluid in the condensing section 8 cooled by the cryogenic refrigerant is cooled to cryogenic temperature and condensed to form the capillary structure 3.
And is moved to the evaporating section 10 of the heat pipe 1 by capillary action.

And the working fluid of the evaporating section 10 is
Absorbs the heat of the ground, which will be the surrounding part 24 of 22, cools the ground and freezes the ground. The working fluid that has absorbed the heat of the ground in the surrounding portion 24 evaporates and maintains the evaporator 10 at a very low temperature, moves inside the heat pipe 1 to the condenser 8, and is cooled again by the condenser 8. Condense.

In this embodiment, the space between the condensing section 8 and the evaporating section 10 of the heat pipe 1 is exposed in the shaft 35. Since the heat pipe 1 is a heat insulating part equipped with a heat insulating material, the heat pipe 1
The transfer of heat from the air in 35 into the heat pipe 1 is hindered by the heat insulating portion.

A tunnel 22 is formed by excavating the inside of the peripheral portion 24 frozen as described above, and a shield tunnel excavator is installed in the tunnel 22. The tunnel 22 is excavated by the shield tunnel excavator thereafter.

Further, the heat pipe 1 is preferably excavated after excavating the tunnel 22 and attaching a segment inside the tunnel 22. If it is necessary to extract the heat pipe 1 before excavating the tunnel 22, the heat pipe 1 is heated for a short time. By doing so, the frozen soil in contact with the heat pipe 1 is softened, and the heat pipe 1 can be easily extracted.

FIGS. 3 and 4 are views for explaining one embodiment of a method of forming the tunnel 22 at the joining position of two shielded tunnel excavators 30 started from both ends of the tunnel 22 to be excavated, Hereinafter, the same portions as those described above are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, two shield tunnel excavators 30 started from both ends of the tunnel 22 to be excavated
When reaching the center of 22, excavation is stopped.

Then, the heat pipes 1 are driven from the rear side of the two shield tunnel excavators 30 into the ground around the tunnel 24 outside the outer shell 31 of the shield tunnel excavator 30, respectively. Pierces the ground of the surrounding portion 24, inserts the heat pipe 1 into the hole,
After the ground is frozen and solidified, each shield-type tunnel excavator 30 is dismantled and taken out of the tunnel 22, and the sediment left in the center of the tunnel 22 is frozen. And the like are carried out of the tunnel 22, and the segment 23 is mounted inside the peripheral portion 24 to form the tunnel 22.

5 and 6 are views for explaining one embodiment of a tunnel forming method for widening the tunnel 22. FIG.

In this embodiment, from both ends of the portion 25 to be widened of the tunnel 22 to the ground around the portion 24 around the portion 25 to be widened,
Driving heat pipe 1 or surrounding part 24
Then, the heat pipe 1 is inserted into the hole, and the heat pipe 1 freezes the ground in the surrounding portion 24.

Then, a portion 25 to be widened inside the frozen and solidified peripheral portion 24 is excavated to form a tunnel provided with the widened portion.

FIG. 7 is a diagram for explaining an embodiment of the invention which is closely related to the present invention.

In the embodiment of the present invention, the heat pipe 1 is inserted into the outer portion 41 of the portion to be excavated as the concave portion 40, and the outer portion 41 is frozen by the heat pipe 1. Next, the earth and sand in the concave portion 40 is excavated, and a retaining wall 42
Is established. And the retaining wall 42 is supported on the outer part 41 by the support rod 43.
And hold it.

〔The invention's effect〕

The present invention relates to a peripheral portion to be excavated by the heat pipe 1.
Since the ground at 24 is cooled, the ground at the surrounding portion 24 can be frozen at an extremely low temperature.

And since it cools to cryogenic temperature, the frozen soil formation period can be shortened.

 As a result, construction costs are reduced.

Further, since the heat pipe 1 is formed as an independent one which is not communicated with the refrigeration unit 15, the refrigerant can be charged,
Alternatively, the refrigerating device 15 can be operated intermittently, and the running cost during the frozen soil storage period can be reduced.

The heat pipe 1 is maintenance-free during operation, can be diverted, and is convenient.

Then, the start of the shield type tunnel excavator or the side wall portion 36 of the shaft 35 to be reached, the joining position of the two shield type tunnel excavators 30, and the portion 50 where the tunnel should be widened
Since the ground in the surrounding portion 24 is frozen at an extremely low temperature, work at those positions is easy.

In the present invention, since the heat insulating material 4 is attached between the condenser section 8 and the evaporator section 10 to provide the heat insulating section 9, the heat insulating section 9 does not need to be cooled. And evaporator
The transfer of heat into the heat pipe 1 from the outside during 10 is prevented.

Therefore, according to the present invention, unnecessary heat transfer can be prevented, and the portion to be frozen can be efficiently cooled.

[Brief description of the drawings]

FIG. 1 is a side view, partially broken and sectioned, of an embodiment of a freezing apparatus using a heat pipe used in the present invention, and FIG. FIG. 3 is an explanatory view of an embodiment of a method of freezing and excavating a side wall portion, FIG. 3 is an explanatory view of an embodiment of a method of freezing and excavating a tunnel at a joint position of a shielded tunnel excavator, FIG. Fig. 5 is a cross-sectional view taken along the line IV-IV in Fig. 3, Fig. 5 is a view for explaining one embodiment of a method of freezing and excavating the widening portion of the tunnel, and Fig. 6 is a VI-VI in Fig. 5. Cross section of the line,
FIG. 7 is a view for explaining one embodiment of a method for forming a concave portion. 1 ... heat pipe, 4 ... heat insulating material, 8 ... condensing part, 9
…… Insulation part, 10 …… Evaporation part, 15 …… Refrigerator, 22 …… Tunnel, 24 …… Peripheral part, 25 …… Part to be widened, 30 …… Shield tunnel excavator, 35 …… 36 ... The side wall.

──────────────────────────────────────────────────続 き Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) E21D 9/04 E21D 9/06 301 E21D 9/00

Claims (3)

(57) [Claims] 1. Launching a shield tunnel excavator, or
At the side wall of the shaft to be reached, which is the surrounding part of the tunnel to be excavated, insert a heat pipe provided with a heat insulating part with a heat insulating material between the condensing part and the evaporating part. A tunnel forming method in which a condensing portion of a heat pipe is cooled by a refrigerant cooled by a refrigerating device, and a ground around a tunnel to be excavated in an evaporating portion of the heat pipe is frozen to excavate a tunnel. 2. At the joining position of two shielded tunnel excavators started from both ends of a tunnel to be excavated,
A heat pipe provided with a heat insulating material and provided with a heat insulating portion was inserted between the condensing portion and the evaporating portion in the ground which is a peripheral portion of the tunnel, and the condensing portion of this heat pipe was cooled by a refrigerating device. Cooled by refrigerant, in the evaporator of the heat pipe,
A tunnel formation method that excavates a tunnel by freezing the ground around the tunnel. 3. A heat pipe provided with a heat insulating material and provided with a heat insulating portion between a condensing portion and an evaporating portion, is inserted into a ground which is a portion surrounding a portion of the tunnel to be widened. Cooling the condensing section with the refrigerant cooled by the refrigerating device,
A method for forming a tunnel by widening a tunnel by freezing a ground around a portion to be widened of a tunnel in an evaporating portion of a heat pipe.