JP3516192B2 - Construction method of large section tunnel and shield machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-section tunnel in which a semi-cylindrical or tubular tunnel structure that resists earth pressure of a natural ground is constituted by a large number of small-diameter shield tunnels formed adjacent to each other in the circumferential direction . The present invention relates to a construction method and a shield machine used when constructing a large-section tunnel thereof .

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 3-250195 discloses a structure of a large-section tunnel of this type and a method for constructing the tunnel. This technology makes it possible to achieve a large tunnel cross section with high quality and at low cost by effectively utilizing the advantages of the shield construction method.

The contents will be briefly described with reference to FIGS. 13 and 14. FIG. 13 is a diagram showing a procedure for constructing the large section tunnel 1, and FIG. 13C is a sectional view of the completed large section tunnel 1. As shown in FIG. (C), the large-section tunnel 1 has a tunnel structure 2 which is formed in a tubular shape as a whole and forms an internal space against the earth pressure of the natural ground, and the inside of the tunnel structure 2. And a tunnel space 3 formed in the. The tunnel structure 2 is composed of a large number of small-diameter shield tunnels (hereinafter, simply referred to as “shield tunnels”) 4 that extend in the longitudinal direction of the tunnel to be constructed and are circumferentially adjacent to each other. Tunnel structure 2
The shield tunnel 4 is formed in a ring shape along the planned line of the tunnel cross section, so that the shield tunnel 4 is formed in a ring shape having a circular cross section as a whole.

Each shield tunnel 4 is composed of a tubular structure 6 assembled by a large number of segments, and a backfilling material 7 such as concrete or mortar which is post-cast on the back side of the tubular structure 6. It has been lined by the lining body 9. However, the diameter of the tubular structure 6 with respect to the inner diameter of the excavation hole excavated by the shield machine is extremely small as compared with a general shield tunnel. The distance between each shield tunnel 4 and the adjacent shield tunnels 4 is set to be smaller than the outer diameter of the shield tunnels 4 themselves, so that the backing lines forming the lining bodies 9 of the shield tunnels 4 adjacent to each other are set. The fillers 7 are polymerized with each other. As a result, the backfill filler 7 of each shield tunnel 4 is continuously integrated.

Construction of the large section tunnel 1 is carried out as follows. First, the tunnel structure 2 including a large number of shield tunnels 4 is preliminarily constructed in the natural ground. That is, first, among the shield tunnels 4 adjacent to each other,
Every other arrangement (leading shield tunnel) 4
A is pre-constructed as shown in FIG. The construction of these preceding shield tunnels 4A can be carried out by the same procedure as a general shield construction method. That is,
A shield machine 10 as shown in FIG. 14 is propelled while excavating the natural ground G by a cutter 11 provided on the front surface thereof, and at the rear of the shield machine 10, an arc-shaped segment is assembled into a ring shape in a ring shape. Going, tubular structure 6
To form. However, in this case, a shield machine 10 having an extremely large tail void is used, whereby the tubular structure 6 is formed to have a diameter smaller than the inner diameter of the excavation hole. In the portion where the tubular structure 6 is formed, the back-filling filler 7 is placed on the back side space, that is, between the tubular structure 6 and the excavation hole. This completes the lining body 9.

As described above, the leading shield tunnel 4A
Is completed, next, as shown in FIG. 13 (b), the trailing shield tunnels 4 are provided between the leading shield tunnels 4A.
Form B. The process of forming the trailing shield tunnel 4B is similar to that of the leading shield tunnel 4A. However, since the separation distance of the leading shield tunnel 4A is smaller than the outer diameter dimension of the shield tunnel 4 itself as described above, 2
When forming the trailing shield tunnel 4B between the leading shield tunnels 4A and 4A of the book, the backfilling material 7 that constitutes the leading shield tunnels 4A and 4A on both sides together with the ground is provided.
Cut a part of at the same time. At this time, since the tubular structure 6 of the leading shield tunnel 4A is formed to have a small diameter, only the backfill filler 7 can be cut without interfering with the tubular structure 6.

Then, as described above, the shield machine 10
By excavating between the two preceding shield tunnels 4A and 4A, assembling the tubular structure 6 in the excavation hole, and sequentially placing the backfill filler 7 on the back side in the subsequent process, the preceding shield tunnel A trailing shield tunnel 4B continuous with 4A is formed, thereby constructing an integral tunnel structure 2 (first step).

After constructing the tunnel structure 2 as described above, the portion surrounded by the tunnel structure 2 in the natural ground is excavated to form the tunnel space 3, whereby the tunnel 1 having a large cross section is completed ( Second step). The excavation of the ground inside the tunnel structure 2 is carried out by a commonly used excavator, but at this stage the tunnel structure 2 has already been constructed, and the ground is supported by this, so support work is carried out. It is not necessary to provide such items.

By the way, when a large number of shield tunnels 4 are connected to form the tunnel structure 2 as described above,
Portion where the shield tunnel 4 is polymerized and integrated (joint portion)
I am worried about water leakage. Therefore, in preparation for such a case, conventionally, a method of injecting a chemical solution into a portion where water leakage may occur has been considered. FIG. 15 is an assumed diagram when a chemical solution is injected. In the figure, 14
Is a liquid medicine injection part, and 13 is a liquid medicine injection pipe. Chemical injection tube 1
3 is formed by inserting a core removing machine or a boring machine into the inner space of the shield tunnel 4, and injects the chemical solution into the ground G outside the shield tunnel 4 through the chemical solution injection pipe 13.

[0010]

However, when the water is stopped at the joint portion of the shield tunnel 4 by injecting the chemical liquid as described above, the cost is high and the tunnel structure 2 is deformed when the tunnel space 3 is excavated. Due to this, when a part of the chemical liquid injecting section 14 is destroyed, it may be difficult to surely stop water.

In view of the above circumstances, the present invention is a structure of a large cross section tunnel which can realize reliable water stop at low cost.
It is an object of the present invention to provide a construction method and a shield machine used for constructing a large cross section tunnel.

[0012]

[0013]

According to the method of constructing a large-section tunnel of the invention of claim 1, a small-diameter shield tunnel extending in the longitudinal direction of the tunnel to be constructed is circumferentially provided on a planned line of the tunnel section to be constructed. A first step of constructing an integrated semi-cylindrical or tubular tunnel structure by forming a large number of adjoining small-diameter shield tunnel linings and polymerizing a part of the linings of adjacent small-diameter shield tunnels; After the first step, a second step of forming a tunnel space by excavating and removing earth and sand surrounded by the tunnel structure is provided, and when the adjacent small-diameter shield tunnel is formed, A part of the lining body of the small-diameter shield tunnel that was formed by In method for constructing a large section tunnel to polymerize a part of the lining of the small-diameter shield tunneling,
When forming the following small-diameter shield tunnel with a shield machine, the cutting surface of the lining body of the preceding small-diameter shield tunnel and the lining of the following small-diameter shield tunnel are accompanied by the advance of the shield machine. In the gap with the body, a water blocking material that closes the gap is continuously laid along the longitudinal direction of the tunnel to be constructed, and when the water blocking material is laid, the water blocking material is used.
Stored in a long linear body and wound on a reel
The waterproofing material from inside the shield machine to the outside
A waterproof sheet installed in the feeding hole provided in the plate.
It is characterized in that it is fed out through the le .

According to a second aspect of the present invention, there is provided a method of constructing a large cross-section tunnel according to the first aspect , wherein among the large number of small-diameter shield tunnels, every preceding small-diameter shield tunnel is precedently constructed, and then the preceding It is characterized in that a small-diameter shield tunnel that follows is constructed between the small-diameter shield tunnels.

According to a third aspect of the present invention, there is provided a method for constructing a large cross-section tunnel according to the first or second aspect , wherein the water blocking material is of an expansion delay treatment type in which the water blocking material expands after touching water at an installation location. Characterize.

[0016]

According to a fourth aspect of the present invention, there is provided a method of constructing a large cross-section tunnel according to any one of the first to third aspects, wherein when the water blocking material is fed out of the shield machine, the positioning means positions the water blocking material. It is characterized by performing.

The shield machine of the invention of claim 5 is the shield machine of claim 1.
In a large section tunnel constructed by the described construction method
A shield machine for forming a small-diameter shield tunneling, the water stopping material laying device for placing the water stopping material at the boundary of the lining of the small-diameter shield tunneling to the adjacent
The water blocking material laying device is provided inside the skin plate.
A continuous water supply material that is installed and is a long linear body.
And the water-stopping material provided on the skin plate
And the outside of the skin plate that is placed in the feeding hole.
And a waterproof seal for preventing water from entering the inside .

[0019]

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Figure 1 is an embodiment of the present invention configured
Large section tunnel 1 constructed by the construction method (Fig. 1
FIG. 3 is an enlarged cross-sectional view showing a part of the tunnel structure 2 (see 3) (the upper end of the annular tunnel structure 2). Similar to the large-section tunnel shown in FIG. 13, the large-section tunnel 1 includes a tunnel structure 2 and a tunnel space 3 inside the tunnel structure 2. The tunnel structure 2 has a large number of small diameters adjacent to each other in the circumferential direction. It is composed of a shield tunnel 4.

Each shield tunnel 4 is covered with a lining body 9 made up of a tubular structure 6 and a backfill filler 7 on the back side thereof, and the lining body 9 of an adjacent shield tunnel 4 is backfilled. The fillers 7 are polymerized with each other. The group of shield tunnels 4 is composed of a leading shield tunnel 4A that is constructed in advance every other one, and a trailing shield tunnel 4B that is constructed by trailing between the leading shield tunnels 4A and 4A. At the boundary (seam) K of the lining body 9 where the tunnels 4A and 4B are superposed on each other, a water blocking material 30 that expands when it comes into contact with water and closes the gap H generated at the boundary K is formed in the longitudinal direction of the large section tunnel. It is installed continuously along. For example, three water-stopping materials 30 are installed at intervals in the radial direction of the tunnel structure 2 having a substantially circular cross section, that is, in the circumferential direction of the trailing shield tunnel 4B. The required number of the water blocking members 30 may be any number as long as it is one or more.

In this way, by installing the water blocking material 30 at the boundary (seam) K of the lining body 9, as shown in FIG. By touching the water blocking material 30, the water blocking material 30 expands and closes the gap H through which water passes, thereby stopping water. Therefore, even when the tunnel structure 2 is slightly deformed during excavation of the internal space (tunnel space 3) and a gap is created at the seam of the shield tunnel 4, the water can be reliably stopped. Further, since the water blocking material 30 is simply installed at the boundary K of the lining body 9 to be polymerized, a costly and troublesome process such as chemical solution injection is not required, and the water impermeability can be enhanced at low cost. it can.

As the water blocking material 30, for example, "Vinon Hydrotight Aqua Jay (trade name: manufactured by CI Kasei Co., Ltd., sold by Iwano Bussan Co., Ltd.)", which is a water-expanded water blocking material for construction, is used. This water-stopping material 30 has been subjected to a special expansion delay treatment (membrane treatment) so as to suppress expansion due to temporary contact with rainwater or groundwater during the period until concrete is poured. It has the function of absorbing water and expanding after reacting with alkaline water.

The cross-sectional shape of this water blocking material 30 is shown in FIG.
As shown in, various types can be appropriately selected. In this case, since each of them is configured as a long linear body, the core material 32 is passed through the central portion of the cross section of the water blocking material body 31 so as to be able to counter the tensile force. As the core material, wire, thin steel plate, glass fiber, carbon fiber, high-strength plastic or the like can be used. here,
The water-stopping material 30A having a circular cross-section is illustrated in (a), the water-stopping material 30B having a square cross-section in (b), and the water-stopping material 30C having a rectangular cross-section in (c).

The construction of this large section tunnel is carried out as follows. First, the leading shield tunnel 4A is formed.
Next, the trailing shield tunnel 4B is formed. And
After constructing the tunnel structure 2 by forming the shield tunnels 4A and 4B, the earth and sand inside the tunnel structure 2 are excavated to form the tunnel space 3. The above basic steps are the same as the conventional one. The difference is that when the trailing shield tunnel 4B is formed by the shield machine 50 shown in FIG. 4, the shield machine 50 moves in accordance with the forward movement of the lining body 9 of the leading shield tunnel 4A as shown in FIG. The point is to perform lining while laying the waterproof material 30 on the cutting surface.

The point will be described in detail below. First, the shield machine 50 for forming the trailing shield tunnel 4B
Will be described. As shown in FIG. 4, this shield machine 50 has a cutter 51 on the front end and a skin plate 52 on the outer periphery.
And an injection pipe 54 of the backfill filler 7 is provided on the rear side of the inside, and a water blocking material is laid on the front side thereof for feeding out the water blocking material 30 in accordance with the forward movement of the shield machine 50. A device 33 is provided. This trailing shield tunnel 4
The shield machine 50 for forming B cuts a part of the backfill filler 7 of the leading shield tunnel 4A together with the earth and sand and advances, and at this time, in order to move smoothly, the leading shield tunnel 4A The backing filler 7 is cut by the shield machine 50 to a size slightly larger than its outer diameter (excessive digging). Therefore, backfill filler 7
A gap 60 is formed between the cut surface of the sheet and the skin plate 52 of the shield machine 50. The waterproof material laying device 33 is
The water blocking material 30 is installed in the gap 60, and the necessary number is provided.

Water-stopping material 30 constructed as a long linear body
Is wound around the reel 35 inside the shield machine 50 and stored in a small form. Skin plate 5
2 is provided with an outlet 55 for leading out the water blocking material 30 to the outside, and for guiding the water blocking material 30 to the outlet 55, it is for leading out smoothly to the outside rear of the skin plate 52. A lead-out pipe 56 is provided. Outlet pipe 56
As shown in detail in FIGS. 6 and 7, a waterproof seal 57 for preventing the intrusion of water from the outside is provided inside the container. The waterproof material laying device 33 includes the reel 35 having the above-mentioned function of feeding the waterproof material 30, the outlet pipe 56, and the waterproof seal 57.

The shapes of the outlet pipe 56 and the waterproof seal 57 are changed according to the sectional shape of the water blocking material 30. Figure 7
Shows the case of the waterproof material 30 having a circular cross section. In this case, as shown in FIG. 8A, an annular waterproof seal 57 made of soft rubber or the like is fitted inside the outlet pipe 56 having a circular cross section. The central hole 57a of the waterproof seal 57 is set to be slightly smaller than the outer diameter of the water blocking material 30, and the water blocking material 30 is inserted therethrough as shown in FIG. Is deformed, and the gap between the water blocking material 30 and the bulging pipe 56 is sealed.

Further, as a waterproof seal other than that, as shown in FIG.
The ones shown in are also conceivable. This waterproof seal 58
Is a bag-shaped one as shown in (a), and after passing through the water blocking material 30 as shown in (b), a liquid such as oil is sealed inside from the communication pipe 58a, so that It swells and seals the gap between the water stop material 30 and the outlet pipe 56.

The waterproof material 30 is the waterproof material laying device 3 described above.
3 is led out of the skin plate 52.
In this case, the water blocking material 30 needs to be installed between the backfill fillers 7 and 7 of the leading and trailing shield tunnels 4A and 4B, and at the time of installation, the backfill filler of the leading shield tunnel 4A. It is necessary to press the water blocking material 30 against the cutting surface of 7. Therefore, in this shield machine 50, as shown in FIG.
As shown in 0, a water stop material pressing mechanism for pressing the water stop material 30 led out to the cutting surface of the backfill filler 7 of the leading shield tunnel 4A behind the outlet 55 of the water stop material 30. 62 is provided.

The water blocking material pressing mechanism 62 is mainly composed of a pressing block 66 housed in an opening 65 formed in the skin plate 52 so as to be retractable. A liquid-tight case 63 for preventing water leakage from the opening 65 is provided inside the opening 65, and a spring 64 for pushing the pressing block 66 outward is provided in the liquid-tight case 63. The pressing block 66 is pushed outward by the force of the spring 64 to be led out of the skin plate 52.
Is pressed against the cut surface of the backfill filler 7 of the leading shield tunnel 4A. In that case, since it is necessary to press and hold the water blocking material 30 in a fixed position, as shown in FIG. 11A, a step portion for positioning and holding the water blocking material 30 is provided at the tip of the pressing block 66. (Positioning means) 66a is provided. In addition, if necessary, as shown in FIG.
A groove (positioning means) 68 may be formed on the cut surface of the backfill filler 7, and the water blocking material 30 may be fitted into the groove 68. The groove 68 can be easily formed by providing a groove cutter on the front side of the outlet of the water blocking material 30.

When the trailing shield tunnel 4B is formed by the shield machine 50, the waterproof material laying device 33 is used by the waterproof material laying device 33.
0 is fed to the outside of the skin plate 52, and is pressed against the cutting surface of the backfill filler 7 of the preceding shield tunnel 4A while being positioned at a predetermined position by the water blocking material pressing mechanism 62. Then, by lining the trailing shield tunnel 4B with the shield machine 50, the water blocking material 30 is installed at the boundary (joint) between the lining bodies 9 of the leading and trailing shield tunnels 4A and 4B. . Finally, the water blocking material 30 is
As the backfill filler 7 of the trailing shield tunnel 4B is solidified, it is fixed from the rear side. Therefore, the water blocking material 30 is
As the shield machine 50 moves forward, it is pulled from the solidified rear portion and is sequentially fed from the reel 35.

The waterproof material 3 that can be set on the reel 35
Since there is a limit to the length of 0
If it disappears, replace it with a new one. At that time, connect the previously laid one and the newly set one before feeding. For connection, the core material 32
Are first connected, and then the water-swellable water blocking material body 31 is connected by an adhesive or the like.

When the water blocking material 30 is laid as described above, the diameter of the excavation hole formed by excavation is as shown in FIG.
If the gap 60 between the excavation hole and the skin plate 52 is set to be smaller than the diameter of the water blocking material 30, it will be crushed between the shield machine 50 and the backfill filler 7 of the preceding shield tunnel 4A. The water blocking material 30 can be installed in a different form, and reliable positioning can be performed. 12A shows the original shape of the water blocking material 30, and FIG. 12B shows the crushed shape. In order to obtain such a crushed shape, it is necessary to select a material that is soft and has a large restoring force for the water blocking material 30.

As described above, the leading shield tunnel 4A
By arranging the trailing shield tunnel 4B while laying the water blocking material 30 on the cutting surface of the lining body of FIG.
It can be installed at the seam (boundary) K of the lining body 9 of A and 4B, and the large section tunnel of FIG. 1 can be constructed. In this case, the shield machine 50 almost only executes the same steps as the general shield construction method, and thus unlike the method using chemical solution injection, constructs a large-section tunnel excellent in water shielding easily at low cost. be able to.

Further, since the water blocking material 30 is wound around the reel 35 and sequentially fed out of the skin plate 52, the water blocking material 30 can be laid while stably supplying the water blocking material 30. Moreover, since the waterproof pipe 57 is provided on the outlet pipe 56 for feeding the water blocking material 30, it is possible to reliably prevent the intrusion of water from the outside into the shield machine 50. Further, since the expansion delay treatment type water blocking material 30 is used, it is possible to store the water blocking material 30 in a small size in the shield machine 30 and perform a desired water blocking function after lining after installation. You can Furthermore, since the water blocking material 30 is positioned at a predetermined position by the stepped portion 66a of the pressing block 66 and the groove 68, stable and reliable water blocking can be performed.

It should be noted that it is sufficient to install the water blocking material 30 only in the places where water leakage may occur. Also,
In the above-mentioned embodiment, the case where the tunnel cross section is circular is shown, but the cross section is not limited to the circular cross section, and it is of course possible to form a horseshoe shape, a semicircular shape, or any other cross sectional shape. Further, in the above embodiment, the leading shield tunnels 4A are formed alternately, and the trailing shield tunnels 4B are formed between the leading shield tunnels 4A. If the construction method of installing the water blocking material 30 at the time of building the trailing shield tunnel is adopted, the water blocking material 30 is easily installed using the shield machine 50 described above. be able to. For example, the present invention can be applied to the case where a certain shield tunnel is formed and the shield tunnels are sequentially installed around the fixed direction.

[0038]

[0039]

As described above, according to the invention of claim 1,
According to this, while laying a water blocking material on the cutting surface of the lining body of the preceding small-diameter shield tunnel, by forming a small-diameter shield tunnel that follows, reliably and easily,
A water blocking material can be installed at the seam (boundary) of the lining body of the adjacent small-diameter shield tunnel . Also, still water
Seal the material through a waterproof seal placed in the feeding hole.
From the inside of the machine to the outside of the skin plate.
Since it is possible to continuously and stably supply the waterproofing material,
In addition, it is possible to prevent water from entering the inside of the shield machine.
It

According to the second aspect of the present invention, since the leading shield tunnels are formed alternately and the trailing shield tunnels are formed between the leading shield tunnels, the leading and trailing shield tunnels alternate. Will be lined up. Therefore, the leading and trailing shield tunnels can be divided into two groups. For example, the lining body of the leading shield tunnel can be set to a condition that is easy to cut when forming the trailing shield tunnel, and when the shield tunnel is constructed. The efficiency of can be improved, and the whole process can be rationalized.

According to the third aspect of the present invention, since an expansion delay treatment type water blocking material that expands after a certain delay time has elapsed after touching the water at the installation location is used, the water is stopped at a predetermined location from the shield machine. In the stage until the material is laid, the contracted state is maintained, the material is set at a predetermined position, and the material expands only after touching the water at the installation position to fulfill the water stop function. Therefore, if the water blocking material is formed as a linear body, it can be stored in a small form in a state of being wound on a reel in the shield machine, and by sequentially feeding the water blocking material from the reel, The waterproofing material can be easily laid on the cutting surface of the lining body of the preceding shield tunnel, and expands after the lining of the trailing shield tunnel to exert the waterproofing effect. Become.

[0042]

According to the fourth aspect of the invention, the position of the water blocking material can be determined, so that stable and reliable water blocking performance can be exhibited.

According to the shield machine of the fifth aspect of the invention, the water blocking material can be laid at the same time when the small diameter shield tunnel is formed. Therefore, it is possible to construct a large cross-section tunnel excellent in water shielding property by simply performing a general shield method without requiring a special process. Well
In addition, the waterproofing material is wound on the reel and the skin
Supply to the outside of the market to ensure a stable supply.
It is possible to lay a water blocking material in place. Well
At that time, the intrusion of water from the outside into the shield machine
It can be stopped with a waterproof seal.

[0045]

[Brief description of drawings]

FIG. 1 is constructed by a construction method which is an embodiment of the present invention.
Is an enlarged fragmentary cross-sectional view of the tunnel structure 2 in a large sectional tunnel.

FIG. 2 is a cross-sectional view showing a state in which a gap H is generated in the II portion of FIG. 1, and the water blocking material 30 expanded by contact with water closes the gap H.

3A and 3B are views showing types of cross-sectional shapes of the water blocking material 30. FIG. 3A is a water blocking material 30A having a circular cross section, FIG. 3B is a water blocking material 30B having a square cross section, and FIG. Water stop material 30
It is each sectional view of C.

FIG. 4 is a cross-sectional view taken along the tunnel longitudinal direction showing a state in which the water blocking material 30 is laid by a shield machine 50 that forms a trailing small-diameter shield tunnel 4B.

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

6 is an enlarged view of a VI portion of FIG.

7 is a sectional view of a mounting portion of the waterproof seal 57 of FIG.

FIG. 8 is a cross-sectional view showing a state (a) when the waterproof seal 57 of FIG. 7 is initially set and a state (b) when in use.

FIG. 9 is a view showing another example of the waterproof seal,
(A) is sectional drawing which shows the state at the time of initial setting, (b) is sectional drawing which shows the state at the time of use.

FIG. 10 is a water blocking material provided in the shield machine 50 shown in FIG.
FIG. 6 is a cross-sectional view showing the configuration of a pressing mechanism 62.

11 is a sectional view taken along the line XI-XI of FIG.
(A) is sectional drawing of a 1st example, (b) is sectional drawing of a 2nd example.

FIG. 12 is a cross-sectional view showing a cross-sectional shape (a) before setting and a cross-sectional shape (b) after setting of the water blocking material 30 laid by the shield machine 50.

13A and 13B are cross-sectional views used for explaining the configuration of a conventional large-section tunnel and a method for constructing the same, in which FIG. 13A is a partial cross-sectional view showing a state in which every other preceding small-diameter shield tunnel is formed. Is a partial cross-sectional view showing a state in which a small-diameter shield tunnel that follows is constructed between a leading small-diameter shield tunnel, and FIG. 6C is a cross-sectional view showing the entire large-section tunnel.

14 is a sectional view taken along the tunnel longitudinal direction showing a state where the small diameter shield tunnel of FIG. 13 is formed by a shield machine.

FIG. 15 is a cross-sectional view showing a water stop structure of a joint of a small-diameter shield tunnel in a conventional large-section tunnel.

[Explanation of symbols]

G Ground 1 Large section tunnel 2 Tunnel structure 3 Tunnel space 4 Small diameter shield tunnel 4A Leading shield tunnel 4B Trailing shield tunnel 9 Lining body 30,30A, 30B, 30C Water stop material 33 Water stop material laying device 35 reel 50 shield machine 52 skin plate 55 outlet 56 outlet pipe (feeding hole) 57, 58 waterproof seal 62 waterproof material pressing mechanism 66 pressing block 66a step portion (positioning means) 68 groove (positioning means) K boundary H gap

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroyuki Kawaguchi 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Shinji Seki 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Kazuo Miyazawa 1-32 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Hiroyuki Kubo 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Hisao Arai 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Hisashi Takenaka 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Minoru Imai 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Hidetake Ishizaki 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. ( 56) References 3-250195 (JP, A) JP flat 4-244799 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) E21D 9/00 E21D 9/06

Claims (5)

(57) [Claims] 1. On a planned line of a tunnel section to be constructed,
A large number of small-diameter shield tunnels extending in the longitudinal direction of the tunnel to be constructed are formed adjacent to each other in the circumferential direction, and a part of the lining body of the adjacent small-diameter shield tunnels is polymerized to form an integrated semi-cylindrical or A first step of constructing a tubular tunnel structure, and a second step of forming a tunnel space by excavating and removing earth and sand inside the tunnel structure after the first step. When forming the adjacent small-diameter shield tunnel,
By cutting a part of the lining body of the small-diameter shield tunnel that was formed in advance with the shield machine of the small-diameter shield tunnel that follows and excavating it while cutting it with the ground, In a method of constructing a large cross-section tunnel in which a part of a lining body of a small-diameter shield tunnel is superposed, in forming the subsequent small-diameter shield tunnel with a shield machine, a small front In the gap between the cutting surface of the lining of the caliber shield tunnel and the lining of the subsequent small-diameter shield tunnel, a water blocking material that closes the gap is continuously provided along the longitudinal direction of the tunnel to be constructed. laid, when laying the water stopping material is stored in a state wound on a reel the water stopping material formed into linear body long, the該止waterstops,
Installed on the skin plate from the inside to the outside of the shield machine .
A method for constructing a large-section tunnel, characterized in that it is fed out through a waterproof seal arranged in the drawn-out hole . 2. Among the large number of small-diameter shield tunnels, every other preceding small-diameter shield tunnel is pre-constructed, and then a trailing small-diameter shield tunnel is provided between the preceding small-diameter shield tunnel. The method for constructing a large cross-section tunnel according to claim 1, wherein the method is constructed. 3. The method for constructing a large cross-section tunnel according to claim 1 , wherein the water blocking material is of an expansion retardation treatment type in which the water blocking material expands after touching the water at the installation location. 4. The construction of the large cross-section tunnel according to claim 1 , wherein the water blocking material is positioned by a positioning means when the water blocking material is fed out of the shield machine. Method. 5. Construction by the construction method according to claim 1.
A shield machine for forming a small-diameter shield tunnel in a large-section tunnel , comprising a waterproof material laying device for installing the waterproof material at the boundary of the lining bodies of the adjacent small-diameter shield tunnels , The waterproofing material laying device is provided inside the skin plate, and sequentially reels out the waterproofing material as a long linear body, the waterproofing material feeding hole provided on the skin plate, and the feeding-out reel. A shield machine, comprising a waterproof seal disposed in the hole to prevent water from entering the skin plate from the outside to the inside.