JPH0830399B2 - Construction method of shield tunnel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a shield tunnel.

[0002]

2. Description of the Related Art Conventionally, a shaft is formed at the depth of a tunnel to be formed in the ground, a shield machine is carried into the shaft and assembled, and the shield machine is propelled. The segment is placed on the wall surface of the hole, and the gap between the wall surface of the hole and the outer surface of the segment is filled with mortar as a back filling material to fill the gap between the segment and the wall surface of the hole. Ground subsidence due to loosening and collapse of mountains is prevented, and water squeezing from the ground into the tunnel is reduced by making the lining of the tunnel composed of segments water-stop.

[0003]

However, in the above-mentioned conventional example, since the mortar is filled in the gap between the wall surface of the hole and the outer surface of the segment, until the mortar hardens and a predetermined water stop is exhibited. It may take some time to leak water into the tunnel during operation, and the segment is used as a reaction force to propel the shield machine.However, since the segment is integrated with the ground of the inner wall of the hole, there is a gap. Since it takes time for the mortar filled in the mortar to harden and develop the desired strength, it takes time for the shield machine to be propelled after the mortar has hardened, and in the uncured mortar state. If it is promoted, there is a problem that sufficient reaction force may not be obtained.

Further, in filling the mortar to be filled in the gap between the wall surface of the hole and the outer surface of the segment, when the mortar manufacturing plant installed on the ground supplies the mortar with a hose or the like, the construction of the tunnel progresses and the If the distance becomes long, there is a risk of clogging in the middle, and in order to prevent this, it is necessary to increase the proportion of water to reduce the viscosity. There is a problem that the curing time becomes longer when the gap is filled with the outer surface and the strength is not preferable.

The present invention has been made in view of the above-mentioned problems of the prior art, and its object is to provide a back filling material filled in a gap between the wall surface of the hole and the outer surface of the segment. It is intended to provide a method for constructing a shield tunnel that is fast-curing and that is unlikely to clog pipes.

[0006]

In order to solve the problems of the above-mentioned conventional examples and to achieve the object of the present invention, the construction method of the shield tunnel of the present invention is such that the shield machine 1 propels the ground 2 in the ground 2. The segment 5 is arranged along the wall surface 4 of the formed hole 3, and the cement and carbon dioxide gas in a powder state are injected into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5. To do.

Further, the cement powder S through the cement powder supply pipe 9 to the injector 8 into the gap 6 between the cement powder supplying device 7 was installed on the ground and the wall 4 of the segments 5 and the hole 3 of the underground And the gap 6 between the underground segment 5 of the cement powder supply pipe 9 and the wall surface 4 of the hole 3
It is also preferable to supply carbon dioxide gas to the cement powder supply pipe 9 in the vicinity of the injection portion 8 to the.

[0008]

According to the present invention having the above-described method, the cement and the carbon dioxide gas in the powder state are injected into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5. Infused powder
The cement in a physical state is hardened by hydration reaction with the groundwater in the gap 6 in the gap 6 , and at this time, the carbon dioxide gas injected into the gap 6 is a mixed liquid of cement and water. Reacts with and generates heat to contribute to the rapid hardening of cement and water. In addition, carbon dioxide gas permeates into the ground 2 through the wall surface 4 of the hole 3 first, and the mixture liquid of cement and water permeates following this carbon dioxide pre-permeation, whereby the surrounding ground is improved by the cement liquid. Will be done. Also, fill the gap 6
The cement used is injected in powder form, so it is necessary for curing.
It takes less time,
From the powder supply device 7 to the wall surface of the underground segment 5 and the hole 3
4 for cement powder supply to the injection part 8 into the gap 6 between
The cement powder S is transferred through the pipe 9 and the cement powder S
Underground segment 5 of body supply pipe 9 and wall surface 4 of hole 3
In the vicinity of the injection part 8 into the gap 6 between the
Ment powder supply pipe 9 to supply the wall surface of the hole 3
A lining that fills the gap 6 between the outer surface of the segment 4 and the outer surface of the segment 5.
Cement, which is a material, is easy to handle and looks like mortar.
Create a clear liquid at the ground plant and
Compared to the one transferred to the back, the tunnel construction progresses and the
Extend the cement powder supply pipe 9 even if it is far from the mine
It's okay to do this, and it will get stuck and harden on the way.
There is no such thing. Also, the water required for the hydration reaction is
The groundwater between the ment 5 and the wall 4 of the hole 3
Since it does not contain water in advance, the injection is stopped
Even inside, there is no risk of hardening in the piping.
It The carbon dioxide gas is supplied near the injection part 8.
By doing so, the cement powder is supplied through the cement powder supply pipe 9.
When the body S is being transferred, the cement powder S causes the shadow of carbon dioxide gas.
It is possible to prevent hardening effect due to sound.
It

[0009]

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the accompanying drawings. To create a shield tunnel, first,
A vertical shaft 10 is formed on the ground 2 from the ground, and the shield machine 1 is carried into the vertical shaft 10 for assembly.
By excavating the ground 2 in the lateral direction to form a hole 3,
This is done by arranging the segment 5 along the wall surface 4 of the hole 3 and injecting the back filling material into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5.

An example of the shield machine 1 is shown in FIG.
Is provided with a cutter wheel 13, a cylindrical body 14 is provided on the outer peripheral portion of the base 11, and a tail seal 14a is provided at the rear end of the cylindrical body 14. Base 11
A shield jack 15 is provided on the. In FIG. 3, reference numeral 16 is an excavated soil carrying-out means such as a screw type earth discharging machine for carrying out the excavated soil.

After excavating the ground 2 by the shield machine 1 having the above-described structure, the segment 5 made of precast concrete or steel plate is assembled in a ring shape in the rear portion of the cylindrical body 14. Here, the cylindrical body 14 is in contact with the wall surface 4 of the hole 3 formed in the ground 2, but when the segment 5 is assembled in a ring shape, the cylindrical body 14 forms a ring shape with the wall surface 4 of the hole 3 in which the cylindrical body 14 is in contact. A gap 6 called a tail void is formed between the outer peripheral surface of the segment 5 to be assembled. And
A back-filling material is injected into the gap 6, but in the present invention, the cement and carbon dioxide gas in a powder state are used as the back filling material.
The water required for the hydration reaction is
The groundwater generated from the wall surface 4 side of the hole 3 between the wall surface 4 and
There is a feature in meeting .

The cement injected into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5 is in the form of powder. FIG. 1 shows a system for supplying cement powder. A cement powder supply device 7 is arranged on the ground, and the cement powder supply device 7 and
An injection portion 8 into a gap 6 between the underground segment 5 and the wall surface 4 of the hole 3 is connected by a cement powder supply pipe 9. The injection part 8 is, for example, as shown in FIG.
A nozzle serving as the injection part 8 is detachably fitted in the injection port 17 provided in the. The cement powder supply pipe 9 is introduced from the cement powder supply device 7 on the ground through the shaft 10 and further into the hole 3, and the cement machine is propelled every time a new segment 5 is set. Powder supply pipe 9
Is extended to attach the nozzle to be the injection portion 8 at the tip thereof to the injection port 17 of the corresponding segment 5 in a detachable manner. A carbon dioxide gas supply device 18 is further arranged on the ground, and the tip of the carbon dioxide gas supply pipe 19 led out from the carbon dioxide gas supply device 18 is connected to the cement powder supply pipe 9 near the injection part 8. I am doing it. The cement powder S is transferred from the cement powder supply device 7 to the injection part 8 through the cement powder supply pipe 9, but in this case, the cement powder S is pressure-transferred by the air being supplied from the injection part 8. The cement powder S is ejected and press-fitted into the gap 6 between the segment 5 and the wall surface 4 of the hole 3 through the injection port 17 of the segment 5, and the carbon dioxide gas pressure-fed from the carbon dioxide gas supply device 7 is further added to the cement powder. Carbon dioxide is mixed into the cement powder S press-fitted into the gap 6 by pressure-feeding the body supply pipe 9 near the injection part 8. The cement powder S press-fitted into the gap 6 reacts with the moisture in the gap 6 in the gap 6 and hardens to fill the gap 6 with the hardened body 20 of cement, and shields with the hardened body 20 of cement and the segment 5. The lining of the tunnel is constructed. In this case, the carbon dioxide gas injected into the gap 6 further acts on the reaction between the cement and water to generate heat, which contributes to the rapid hardening of the cement and water. Become. Further, carbon dioxide gas permeates into the ground 2 through the wall surface 4 of the hole 3, and the mixed liquid of cement and water permeates following the permeation of the carbon dioxide gas, whereby the surrounding ground is improved by the cement liquid. In addition, the ground improved peripheral ground, the cement hardened body 20, and the segment 5 are integrated.

After filling the gap with a mixture of cement and carbon dioxide gas, the shield jack 15 is pressed against the segment 5 or the supporting material of the segment 5 to propel the shield machine 1 to dig the hole 3. Then, the extension of the hole 3 is newly formed in the ground 2 by the propulsion of the shield machine 1, and the segment 5 is further arranged along the wall surface 4 of the hole 3 and at the tip of the cement powder supply pipe 9 described above. The nozzle forming the injection part 8 is reconnected to the injection port 17 of the new segment 5 to inject the cement powder and carbon dioxide gas into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5. .
Here, a check valve is provided at the injection port 17 of the segment 5, or the injection port 17 after the nozzle forming the injection portion 8 is removed is shielded by an arbitrary shielding material.

In the above embodiment, the injection port 17 is provided in the segment 5.
The injection port 17 is provided with a nozzle that constitutes the injection part 8 at the tip of the cement powder supply pipe 9, and the cement powder is introduced into the gap 6 between the wall surface 4 of the hole 3 and the outer surface of the segment 5. Although an example of injecting carbon dioxide gas has been shown, as shown in FIG. 4, an injecting portion 8 may be provided at the rear end of the cylindrical body 14 to inject cement powder and carbon dioxide gas into the gap 6.

Further, a heating means may be provided in the middle of the carbon dioxide gas supply device 18 and the carbon dioxide gas supply pipe 19 to heat and supply the carbon dioxide gas. When the carbon dioxide gas is heated and supplied, the reaction between the mixed liquid of cement and water and the carbon dioxide gas is further promoted in the gap 6, and the early hardening of the cement is further accelerated. Further, in the embodiment shown in the accompanying drawings, the carbon dioxide gas supply pipe 19 is connected to the cement powder supply pipe 9 near the injection part 8 to supply carbon dioxide gas to the cement powder supply pipe 9. However, the cement powder and the carbon dioxide gas are separately injected into the gap 6 between the segment 5 and the wall surface 4 of the hole 3 to form the gap 6
You may make it mix in.

In the case of the embodiment in which the carbon dioxide gas supply pipe 19 is connected to the cement powder supply pipe 9, as described above, the carbon dioxide gas supply pipe 9 is connected to the cement powder supply pipe 9 near the injection part 8. When carbon dioxide is supplied to the cement powder supply pipe 9 for connecting the cement powder 19 and transferring the cement powder, the length of the cement powder supply pipe 9 from the cement powder supply device 7 on the ground to the injection part 8 is increased. Even if it becomes long, when the cement powder is transferred through the long cement powder supply pipe 9, the cement powder does not cause a hardening action due to the influence of carbon dioxide gas, and the cement powder is supplied in the cement powder supply pipe 9. It is preferable because it can prevent the body from hardening and clogging. However, when it is necessary to mix the cement powder and the carbon dioxide gas more effectively, the carbon dioxide gas supply pipe 1 may be provided at an arbitrary position in the middle of the cement powder supply pipe 9.
9 is connected, or when the cement powder is transferred from the cement powder supply device 7 through the cement powder supply pipe 9, carbon dioxide is pressure-fed by a compressor, and the cement powder is transferred by the flow of this carbon dioxide. You may do it.

[0018]

According to the present invention, as described above, the segments are arranged along the wall surface of the hole formed in the ground by the propulsion of the shield machine, and the space between the wall surface of the hole and the outer surface of the segment is provided. Since powdered cement and carbon dioxide gas are injected into the gap, there is a risk that they may become blocked and hardened in the middle of the piping.
In addition, the water required for the hydration reaction is
Since it is covered by the groundwater between the walls, water is not included beforehand.
Not in the pipe, even if the injection is stopped.
There is no risk of curing. And carbon dioxide is
By supplying near the injection part, the cement powder supply
While transferring the cement powder through the supply pipe,
The powder does not cause a hardening effect due to the effect of carbon dioxide.
You can do it. Also, cement powder should be
Since it reacts with the moisture in the gap and hardens, mortar and
Compared to when it is injected into the gap in the state of cement milk,
The ratio of water in the space is small and the time required for curing is
It will be shorter. Moreover, when the powdered cement reacts with the moisture in the gap and hardens, the carbon dioxide gas injected into the gap reacts with the mixed liquid of cement and water to generate heat, which accelerates the hardening of the cement and water. As a result, the cement hardened body filled in the gap can exhibit a predetermined strength in a short period of time and a predetermined water stoppage property, and it is possible not only to prevent the depression of the ground but also to protect the shield tunnel of the shield machine. The formation period can be shortened and water intrusion into the tunnel can be prevented.Furthermore, the carbon dioxide gas injected into the gaps pre-penetrates into the ground from the wall surface of the hole. The mixed liquid permeates, which improves the surrounding ground with cement liquid, so that the hardened cement and the segment filled in the gap with the surrounding ground and the segment are integrated, resulting in stronger strength and waterproofing. Those capable of forming a high lining.

Further, the cement powder is transported through the cement powder supply pipe from cement powder supplying device which is installed on the ground in the injection portion into the gap between the wall of the underground segment and the hole, the cement powder In the case where the carbon dioxide gas is supplied to the cement powder supply pipe near the injection part into the gap between the underground segment of the supply pipe and the wall surface of the hole, between the wall surface of the hole and the outer surface of the segment. It is easier to handle cement, which is the back filling material that fills the gaps, than when using mortar or cement milk as the back filling material.
In particular, even if the tunnel construction progresses and is far away from the shaft, it is only necessary to extend the cement powder supply pipe, and there is no risk of it being blocked or hardened during the process. By supplying near
When the cement powder is being transferred through the cement powder supply pipe, the cement powder can be prevented from hardening due to the effect of carbon dioxide gas, the cement powder supply pipe is less likely to be clogged, and the hydration reaction The water required for Segume
The groundwater between the ground and the wall of the hole will cover it.
Since it does not contain water,
Also, there is no risk of hardening in the piping, and as a result, the management of the cement powder supply piping is not complicated.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an entire embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which cement and carbon dioxide gas are being injected into the gap portion of the above.

FIG. 3 is a schematic sectional view showing an example of a shield machine used in the above.

FIG. 4 is a cross-sectional view of another embodiment in a state where cement and carbon dioxide gas are injected into the gap portion of the above.

[Explanation of symbols]

 1 Shielding machine 2 Ground 3 Hole 4 Wall surface 5 Segment 6 Gap 7 Cement powder supply device 8 Injection part 9 Cement powder supply pipe

Claims (2)

[Claims] 1. A segment is disposed along a wall surface of a hole formed in the ground by the propulsion of a shield machine, and a cement in a powder state is provided in a gap between the wall surface of the hole and an outer surface of the segment. And a method of constructing a shield tunnel, which comprises injecting carbon dioxide. 2. A cement powder supply device installed on the ground
To the gap between the underground segment and the wall of the hole
Transfer the cement powder through the cement powder supply pipe to
And the underground segment of this cement powder supply pipe
Carbon dioxide gas near the injection part into the gap between the hole wall and
The method for constructing a shield tunnel according to claim 1 , wherein the cement is supplied to a cement powder supply pipe .