JPH0369438B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention is applicable to shield tunnel excavation when simultaneously excavating one tunnel from both ends using two shield machines and joining them in the middle. Regarding underground bonding method.

``Prior Art'' Conventionally, as an underground joint construction method for this type of shield tunnel, the one shown in FIG. 5 is known.

In the figure, the symbol G is the ground near the junction of the shield tunnel that has been excavated from both ends.
Inside the ground G, there is one tunnel on the right side of the page.
The shield machine 1 that excavated the tunnel Ta and the shield machine 2 that excavated the other tunnel Tb are facing each other on the left side, leaving the ground Gi at a predetermined interval (about 30 cm). The walls of the tunnels Ta and Tb formed behind the shield machines 1 and 2 are lined with segments 3a, 3a, . . . , 3b, 3b, . In addition, the tips of the shield machines 1 and 2 are provided with holes drilled into the ground G at a predetermined angle of inclination (α = 17° to 25°) with respect to the skin plates 1a and 2a, and at a predetermined pitch in the circumferential direction. Freezing tubes 4a and 4b are installed, and skin plates 1a and 2
A and the frontmost segments 3a and 3b have a structure in which a freezing tube (not shown) is attached to the entire inner peripheral surface.

By circulating brine through the perforated freezing tubes 4a and 4b installed on the skin plates 1a and 2a and the pasted freezing tubes, the ground Gi
After freezing the ground Gf on the outer periphery of the skin plates 1a, 2a so as to surround it, the front parts 5a, 5b of the shield machines 1, 2 are dismantled, and then the ground Gf left between the shield machines 1, 2 is dismantled. By excavating the ground Gi and lining its walls, the tunnels Ta and Tb excavated from the left and right are joined, completing the shield tunnel.

``Problems to be Solved by the Invention'' However, in the conventional shield tunnel joining method and device, both shield machines do not come into contact with each other, creating a gap of approximately 30 cm, which makes it difficult to stop water and retain soil. In addition, the freezing method, which is mainly used as an auxiliary construction method, requires a lot of construction cost and construction time, and the strength of the frozen soil mixed with salt during construction under the seabed is poor. There were problems such as the expansion of frozen soil during freezing and subsidence during thawing, and the difficulty of managing frozen soil.

The present invention has been made in view of the above-mentioned problems, and it is possible to ensure safe sealing and water stoppage against earth water pressure acting from the ground G near the tunnel joint to the joint. The purpose of the present invention is to provide an underground joining method for shield tunnels that can significantly reduce the construction cost and construction period required for tunnel joining.

"Means for Solving the Problems" The present invention has a skin plate having a distal end portion that is double formed by an outer cylinder and an inner cylinder, and a penetrating ring is housed between the outer cylinder and the inner cylinder. A step of excavating a tunnel by using a first shield machine as a set, and a second shield machine whose skin plate has a tip end portion that is double formed by an outer cylinder and an inner cylinder having the same diameter as the first shield machine. Immediately before the end of the tunnel excavation process, the penetrating ring of the first shield machine is slid forward along the axis of the first shield machine, and the penetrating ring allows the first and second shield machines to move forward. There is a process of covering the ground at the tunnel joint that was left during The above-mentioned problems are solved by configuring an underground joint construction method for shield tunnels, which consists of the steps of excavating a mountain and further lining the wall surface of the joint by pouring concrete on the inner surface of the skin plate. ing.

Here, it is preferable to provide a water stop means between the outer cylinder and the inner cylinder of the skin plate of the first and second shielding machines. Further, it is also preferable that the cutter devices of the first and second shielding machines are provided with a cutter portion that is freely expandable and retractable in the radial direction.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIGS. 1 to 4 are diagrams illustrating an underground joining method for a shield tunnel, which is an embodiment of the present invention. In these figures, the same elements as those shown in FIG. 5 are given the same reference numerals.

In the figure, the symbol G is the ground near the junction of the shield tunnel that has been excavated from both ends.
In this ground G, the first shield machine 1 excavates a first tunnel Ta on the right side of the page using a cutter device 10 installed at its front part, and the second shield machine 2 excavates the first tunnel Ta on the right side of the page. The other tunnel Tb is excavated on the left side by a cutter device 20 provided at the front. The wall surface of the tunnel Ta formed behind the shield machine 1 is composed of segments 3a, 3a, . . . assembled inside the shield machine 1.
In addition to the primary lining, the shield machine 1
The wall surface of the tunnel Tb formed behind the shield machine 2 is primarily lined with segments 3b, 3b, . . . assembled inside the shield machine 2.

The first shield machine 1 is provided with a skin plate 1a that is formed into a cylindrical shape and forms the outer shell of the main body of the shield machine 1. This skin plate 1
The tip portion 1b of a is double formed by an outer cylinder 11 formed to have the same diameter as the skin plate 1a, and an outer cylinder 12 formed to have a smaller diameter than this outer cylinder 11. Between the outer cylinder 11 and the outer cylinder 12, a cylindrical penetrating ring 13 that is integrally formed or divided into a plurality of pieces is provided.
is stored, and a bulge 13a is formed at the rear end of the penetrating ring 13. In addition, a highly viscous water-stopping agent such as rubberized asphalt or grease is filled between the outer cylinders 11 and 12, thereby providing a water-stopping means between the outer cylinders 11 and 12. is configured. A partition plate 14 formed perpendicularly to the axis of the shield machine 1 is provided inside the outer cylinder 12 . Outer cylinder 12
and the skin plate 1a are connected by a ring-shaped pressure plate 15 formed perpendicular to the axis of the shield machine 1. On the front surface of this pressure plate 15, pressure jacks 17, 1 are provided in the circumferential direction.
7, .
It is in contact with the rear surface of the Further, on the rear surface of the pressure plate 15, there are propulsion jacks 18, 1 in the circumferential direction.
A plurality of propulsion jacks 8, .

The cutter device 10 provided at the front part of the first shielding machine 1 is formed to have a slightly smaller diameter than the outer cylinder 12, and its shaft body 19 is pivotally supported by the partition plate 14, so that the cutting device 10 is provided at the front part of the first shielding machine 1. is supported by A cutter portion 10a that is extendable and retractable in the radial direction of the shielding machine 1 is provided at the edge of the cutter device 10.

The second shield machine 2 is provided with a skin plate 2a formed in a cylindrical shape having the same diameter as the first skin plate 1a, and this skin plate 2a
As in the first shielding device 1, the tip end 2b is constructed of an outer cylinder 21 formed to have the same diameter as the skin plate 2a, and an inner cylinder 22 formed to have a smaller diameter than this outer cylinder 21. is formed. A highly viscous water-stopping agent such as rubberized asphalt or grease is filled between the outer cylinder 21 and the inner cylinder 22, thereby forming a water-stopping means between the outer cylinder 21 and the outer cylinder 22. has been done. A partition plate 24 formed perpendicularly to the axis of the shield machine 2 is provided inside the outer cylinder 22 . Outer cylinder 22
and the skin plate 2a are connected by a ring-shaped pressure plate 25 formed perpendicular to the axis of the shield machine 2. Further, a ring 23 is provided inside the skin plate 2a, and a plurality of propulsion jacks 28, 28, . . . are attached to the rear surface of the ring 23 in the circumferential direction. The working end 28a of the propulsion jack 28 is in contact with the side surface of the segment 3a at the tip.

The cutter device 20 provided at the front part of the second shield machine 2 is formed to have a slightly smaller diameter than the outer cylinder 22, and its shaft body 29 is pivotally supported by the partition plate 24. It is supported by 2. At the edge of this cutter device 20, the first
Similar to the cutter device 10, the shield machine 2 is provided with a cutter portion 20a that is extendable and retractable in the radial direction.

In addition, the first and second shield machines 1 and 2 include
Mud soil press-in pipes 16 and 26 are provided, respectively, and the open ends of these pipes 16 and 26 are located at the tip of each shield machine 1 and 2.

Next, the underground bonding method of the present invention will be explained using FIGS. 1 to 4.

(i) First, from the right side in Fig. 1, the ground G
is excavated, the walls of the excavated pit are lined with segments 3a, 3a,..., and the propulsion jack 1 is
8, 18, . . . to build one tunnel Ta. At this time, the telescopic cutter portion 10a of the cutter device 10 is extended so that the cutter device 10 can excavate a tunnel having at least the same diameter as the outer cylinder 11. At the same time, from the left side in FIG.
0, excavate the ground G, and line the walls of the excavated pit with segments 3b, 3b,...
By applying a reaction force to these segments 3b, 3b, . . . and driving the propulsion jacks 28, 28, . . ., the other tunnel Tb is constructed. At this time, the telescopic cutter section 2 of the cutter device 20
0a is extended so that this cutter device 20 can excavate a tunnel having at least the same diameter as the skin plate 2a. (FIG. 1) Then, the first shield machine 1 and the second shield machine 2 are made to face each other with a predetermined length of ground Gi (approximately 30 cm to 1 m) left at the junction of the tunnel. At this time, the extended cut portion 10
a, 20a is shortened to its original length. Here, the cutter devices 10 and 20 each have an outer cylinder 1.
Since it is formed with a slightly smaller diameter than 2 and 22,
If the cutter parts 10a, 20a are shortened, earth and sand will enter the shield machines 1, 2 through the gaps between the outer cylinders 12, 22 and the cutter devices 10, 20. Therefore, mud is forced into the above-ground Gi at the tunnel junction using the pipes 16 and 26 to prevent the intrusion of earth and sand and to prevent the ground Gi from sinking. (Fig. 2) (ii) Next, press jack 1 of first shield machine 1
7 until the tip of the penetrating ring 13 is inserted into the gap between the outer cylinder 21 and the inner cylinder 22 of the second shield machine 2.
3 is slid forward along the axis of the shield machine 1. This causes the penetrating ring 13 to
This means that the ground Gi remaining at the tunnel junction between the shield machine 1 and the second shield machine 2 was covered. Here, the outer cylinders 11 and 21 and the inner cylinder 1
As the penetration ring 13 is pushed out, the rubberized asphalt or grease filled between the skin plates 1a and 22 is applied to each skin plate 1a and 2a.
It seeps into the ground Gi at the joint from the gap between the two. Therefore, the leaching of the rubberized asphalt and the grease can further ensure the watertightness of the joint against the ground Gi. Furthermore, when performing secondary lining on the tunnels Ta and Tb, before lining the tunnel joints, concrete is previously wrapped around the inner surfaces of the segments 3a and 3b up to the vicinity of the joints. (Fig. 3) (iii) Then, the cutter devices 10 and 20 are disassembled and removed, the partition plates 14 and 24 are cut and removed, and both ends of the penetration ring 13 are inserted into the outer cylinder 1.
Weld to 2 and 22. Next, the wall surface of the joint is lined by pouring concrete 31 including the thickness for the secondary lining on the inner wall surface of the skin plate. Here, for the purpose of reinforcing the tunnel joint, a support structure 32 made of, for example, H-shaped steel may be provided on the inner surface of the outer cylinders 12, 22. (Figure 4) By the above construction method, construction of the shield tunnel joint is completed. Here, the ground Gi at the tunnel joint is covered by the penetration ring 13 provided at the skin plate tip 1b of the first shield machine 1, so the penetration ring 13 prevents the earth retaining at the joint from water-stopping. It is done. Therefore, the shield tunnel joint can be constructed without using auxiliary construction methods such as the conventional freezing construction method, and it does not require much construction cost and construction time as in the conventional freezing construction method. , construction of joints can be carried out. Therefore, earth retention and water stoppage against earth water pressure acting from the ground G near the tunnel joint to the joint can be ensured, construction can be carried out safely, and the construction cost and construction period required for tunnel joint can be reduced. It becomes possible to provide an underground joint construction method for shield tunnels that can significantly reduce costs.

In particular, in this embodiment, the outer cylinders 11 and 21 and the outer cylinder 12 of the first and second shield machines 1 and 2,
Since a water stop means made of rubberized asphalt or grease is provided between the penetrating ring 13 and
This makes it possible to ensure water stoppage when covering the ground Gi at the tunnel joint. Similarly, the cutter device 10 of each of the shield machines 1 and 2,
Cut portions 10a, 20 that are expandable and retractable in the circumferential direction are provided at 20.
a is provided, the skin plates 1a, 2a
Since the phenomenon of reduction in the excavation diameter due to the double formation of the tip portions 1b and 2b,
It becomes possible to reduce the propulsion resistance applied to the shield machines 1 and 2 during tunnel excavation.

In addition, in this embodiment, the cutter device 1
0 and 20 are formed to have a slightly smaller diameter than the inner cylinders 12 and 22, so if the partition plates 14 and 24 are used to support and fix the cutter apparatuses 10 and 20, the cutter apparatuses 10 and 20 can be connected to the inner cylinders 12 and 22. , 22 and the partition plates 14, 45. Therefore, in step (ii), even if the propulsion jacks 18, 28 are further driven to bring the shield machines 1, 2 closer together after the cutter parts 10a, 20a are shortened, the cutter devices 10, 2
0's never touch each other. Therefore, by bringing the shield devices 1 and 2 closer together and facing each other, it is possible to further ensure water-stopping properties at the tunnel junction.

It should be noted that the method for underground joining of a shield tunnel according to the present invention is not limited to the above-mentioned embodiments. For example, the mechanism for sliding the penetrating ring 13 forward is not limited to the pressing jack 17 as in the above embodiment, but the mechanism for sliding the penetrating ring 13 forward is not limited to the pressing jack 17 as in the above embodiment.
Any mechanism that can slide will suffice.

``Effects of the Invention'' As explained above, in the present invention, the tip of the skin plate is double formed by an outer cylinder and an inner cylinder, and a penetrating ring is housed between the outer cylinder and the inner cylinder. A tunnel is excavated using a pair of a first shield machine and a second shield machine, which is double formed by an outer cylinder and an inner cylinder, the tip of which has a skin plate having the same diameter as the first shield machine. immediately before the end of the tunnel excavation step, a step of covering the ground at the tunnel joint portion left between the first and second shield machines with the penetrating ring; The shield machine is dismantled with the skin plate of the second shield machine remaining, the ground at the joint is excavated, and concrete is poured on the inner surface of the skin plate to line the wall of the joint. Since the method for underground joining of a shield tunnel is constructed, the earth retaining and water stoppage of the joint part are performed by the penetration ring provided on the first shield machine. Therefore, the shield tunnel joint can be constructed without using auxiliary construction methods such as the conventional freezing construction method, and it does not require much construction cost and construction time as in the conventional freezing construction method. ,
Construction of joints can be carried out. Therefore, underground joints of shield tunnels can ensure earth retaining and water stoppage at tunnel joints, can be safely constructed, and can significantly reduce the construction cost and construction period required for tunnel joints. It becomes possible to provide construction methods.

In addition, if a water stop means is provided between the outer cylinder and the inner cylinder of the first and second shielding machines 1, the water stop when covering the ground at the tunnel joint with the penetrating ring will be more reliable. can do. Similarly, if the cutter device of each shield machine is provided with a circumferentially expandable cutter part, it is possible to reduce the propulsion resistance applied to the shield machine during tunnel excavation.

[Brief explanation of drawings]

FIG. 1 shows a shield/shield which is an embodiment of this invention.
Figure 2 is a diagram similar to Figure 1; Figure 3 is a diagram similar to Figure 1; Figure 4 is a diagram similar to Figure 1; FIG. 5 is a diagram showing a state in which tunnels are joined by the freezing method, which is a conventional underground joining method for shield tunnels. G...Ground, Gi...Tunnel joint ground, Ta
...Tunnel, Tb...Tunnel, 1...First shield machine, 2...Second shield machine, 1a, 2
a...Skin plate, 1b, 2b...Skin plate tip, 3a, 3b...Segment, 1
0, 20... cutter device, 10a, 20a... cutter portion, 11, 21... outer cylinder, 12, 22... inner cylinder, 13... penetration ring, 18, 28... propulsion jack.

Claims (1)

[Scope of Claims] 1. A construction method using two shield machines that propel underground while excavating the ground with a cutter device installed at the front and assembling segments for the primary lining inside. This is an underground bonding method for shield tunnels in which a tunnel is completed by excavating tunnels from both ends of the tunnel and joining them in the middle. A first shield machine is formed double and has a penetrating ring stored between the outer cylinder and the inner cylinder, and the tip of the skin plate has an outer cylinder and an inner cylinder having the same diameter as the first shield machine. A step of excavating a tunnel using a second shield machine double-formed by a cylinder, and immediately before the end of the tunnel excavation process, the penetrating ring of the first shield machine is removed from the first shield machine. a step of sliding the shield machine forward along the axis to cover the ground at the tunnel joint left between the first and second shield machines with the penetrating ring; Dismantle the shield machine with the skin plate of the shield machine in step 2 left in place, excavate the ground at the joint, and then pour concrete on the inner surface of the skin plate to line the wall of the joint. An underground bonding method for shield tunnels comprising the following steps. 2. An underground shield tunnel according to claim 1, characterized in that a water stop means is provided between the outer cylinder and the inner cylinder of the skin plates of the first and second shield machines. Joining method. 3. The method for underground joining of a shield tunnel according to claim 1, wherein the cutter devices of the first and second shield machines are provided with cutter portions that are expandable and retractable in the radial direction.