JPH064998B2 - Underground joining method for shield tunnel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial field of application" The present invention relates to a shield tunnel for simultaneously excavating one tunnel from both ends of the tunnel by using two shield machines and joining the tunnels on the way. Underground connection method.

"Prior Art" Conventionally, as shown in Fig. 7, an underground bonding method for this type of shield tunnel is known.

In the figure, reference symbol G is the ground near the junction of the shield tunnels that have been excavated from both ends. Within the ground G, the shield machine 1 excavating one tunnel Ta on the right side with respect to the paper surface and the shield machine 1 on the left side. The shield machine 2 excavating the other tunnel Tb faces each other while leaving a natural ground Gi at a predetermined interval (about 30 cm). And the shield machine 1,
Walls of the tunnels Ta and Tb formed at the rear of 2 are lined with segments 3a, 3a, ..., 3b, 3b ,. Further, the tip end portions of the shield machines 1 and 2 have a predetermined inclination angle (α) with respect to the skin plates 1a and 2a.
= 17 ° to 25 °), and perforation type freezing tubes 4a, 4b are installed in the ground G at a predetermined pitch in the circumferential direction, and at the skin plates 1a, 2a and the frontmost segments 3a, 3b. Is a freeze tube attached to the entire inner surface (not shown)
Has been installed.

The brine is circulated in the perforation type freezing tubes 4a, 4b and the sticking freezing tubes installed on the skin plates 1a, 2a, so as to surround the natural ground Gi and the natural ground Gf at the outer peripheral portion of the skin plates 1a, 2a. After freezing
Dismantle the front parts 5a, 5b of the shield machines 1, 2, and then
The ground Gi left between the shield machines 1 and 2 is excavated,
By covering the wall surface, the tunnels Ta and Tb excavated from the left and right are joined to complete a shield tunnel.

“Problems to be solved by the invention” However, in the conventional shield tunnel joining method, a gap of about 30 cm is usually formed between both shield machines at the joining point, and water stoppage and earth retention are complete. It is difficult to say that there is a problem with safety, and the freezing method mainly used as an auxiliary method requires a lot of construction cost and construction period, and the strength of frozen soil mixed with salt decreases during construction under the seabed. However, there were problems such as the influence of frozen soil expansion during freezing and ground subsidence during thawing, and the difficulty in managing frozen soil.

The present invention has been made in view of the above problems, and reliably joins two shield machines excavated from both sides in the ground within a predetermined dimensional error range, thereby providing a natural ground near a tunnel junction. Sealing and stopping water against the earth pressure acting on the joint part of the shield machine from G can be performed securely, and the joint work can be performed safely, and the construction period required for the underground joint work of the tunnel is greatly shortened, and It is an object of the present invention to provide an underground joining method for shield tunnels that can reduce construction costs.

"Means for Solving the Problems" In order to solve the above problems, the present invention has a skin plate in which the distal end portion is double formed by an outer cylinder and an inner cylinder, and the outer cylinder and the inner cylinder are The first shield machine in which the penetration ring is housed between the first shield machine and the front end of the skin plate are doubled by an outer cylinder and an inner cylinder having the same diameter as the first shield machine. A tunnel is excavated from both sides by using a second shield machine having a penetration room as one set, and before the completion of the tunnel excavation process, the first shield machine and the second shield machine are stopped at a predetermined interval and After confirming the relative position by horizontal bowling with a steel pipe between the first shield machine and the second shield machine, the other shield machine is controlled while the direction control is performed on the at least one shield machine. Of the first shield machine, and then the penetration ring of the first shield machine is slid forward to penetrate into the penetration chamber of the second shield machine to leave the space between the first and second shield machines. After covering the ground of the tunnel junction, dismantling the shield machine while leaving the skin plates of the first and second shield machines to join the tunnel, and then placing concrete on the inner surface of the skin plate. Then, the wall surface of the joint portion is lined.

[Examples] Hereinafter, the present invention will be described with reference to the drawings. 1 to 6 are views for explaining one embodiment of the underground joining method for a shield tunnel of the present invention. In these figures, the same components as those of the conventional technique shown in FIG. 7 are designated by the same reference numerals.

In the figure, reference numeral G is a ground near the junction of the shield tunnel excavated from both ends, and in this ground G, the first shield machine 1 is provided by the cutter device 10 provided in the front part thereof. , The first tunnel T on the right side of the page
In addition, a second shield machine is excavating the other tunnel Tb on the left side by the cutter device 20 provided in the front portion thereof. The wall surface of the tunnel Ta formed at the rear of the shield machine 1 is formed by the segments 3a, 3a, ...
The wall surface of the tunnel Tb formed behind the shield machine 2 is subjected to the primary lining by the segments 3b, 3b, ... There is.

The first shield machine 1 is provided with a skin plate 1a formed in a cylindrical shape and forming an outer shell of the main body of the shield machine 1. The tip portion 1b of the skin plate 1a is double formed by an outer cylinder 11 having the same diameter as the skin plate 1a and an inner cylinder 12 having a smaller diameter than the outer cylinder 11. Between the outer cylinder 11 and the inner cylinder 12, a penetrating ring 1 which is cylindrical or is divided into a plurality of pieces.
3 is stored, and a lip seal, an O ring, and an O seal (not shown) are provided between this and the outer cylinder 11 and the inner cylinder 12.
Water stop means such as is provided. In addition, a partition plate 14 fixed orthogonally to the outer cylinder 11 and the inner cylinder 12 is provided in the skin plate 1a, and the shaft portion 15 of the cutter device 10 is mounted on the central axis of the partition plate 14. In the vicinity of the shield tail portion 1c, at predetermined intervals in the circumferential direction,
.. for propelling the shield machine 1 by applying a reaction force to the side surface of the segment 3a are fixed. In addition, a plurality of slits (not shown) extending in the axial direction of the penetrating ring 13 are formed at a predetermined interval in the circumferential direction at the tip of the penetrating ring 13 integrally formed in the cylindrical shape. It may have a degree of freedom of deformation so that it can easily penetrate into a penetration chamber described later.

The second shield machine 2 includes the first skin plate 1
A cylindrical skin plate 2a having the same diameter as a is provided, and a tip portion 2b of the skin plate 2a has an outer cylinder 21 having the same diameter as the outer cylinder 11 of the first shield machine 1 and the inner shell 21a. The tube 12 and the inner tube 22 having the same diameter form a penetration chamber 23 for penetrating the penetration ring 13 by being doubled. A thermoplastic filler (not shown) such as asphalt or polymer resin is provided in the penetration chamber 23 so that the penetration chamber 23 is not clogged with soil, gravel or the like when the shield machine 2 is propelled. It is closely packed and a heating means such as a heating wire is provided so as to surround the thermoplastic filler. The outer cylinder 2 is inside the skin plate 2a.
1 and the inner cylinder 22 are provided with a partition plate 24 fixed orthogonally thereto, and the cutter device 2 is provided on the central axis of the partition plate 24.
0 shaft portion 25 is attached, and propulsion jacks 26, 26, ... for propelling the shield machine 2 by fixing reaction force to the side surface of the segment 3b at fixed intervals in the circumferential direction near the shield tail portion 2c are fixed. It has been configured.

Further, in the cutter devices 10 and 20 provided at the front portions of the first and second shield machines 1 and 2, tip blades 10a and 20a are provided at outer ends of outer cutters 11 and 21 and inner cylinders 12 and 2, respectively.
The shaft portions 15 and 25 are configured to be movable in the front-rear direction along the central axis of the skin plates 1a and 2a, while being mounted to be expandable and contractible in the radial direction between the partition plate 14 and As shown in FIG. 3, pipes 17, 17 and 27, 27 for pouring mud for pouring mud into the front part of the shield machine are attached to 24.

Next, the underground joining method of the present invention will be described with reference to FIGS. 1 to 6.

(i) First, from the right side in FIG. 1, a ground device G is excavated by the cutter device 10 using the first shield machine 1, and the lining of the segments 3a, 3a, ... , And the reaction force is applied to the segments 3a, 3a, ... To drive the propulsion jacks 16, 16 ,.
To build. At the same time, from the left side in FIG. 1, the ground device G is excavated by the cutter device 20 using the second shield machine 2, and the segment 3 is formed on the wall surface of the excavated mine.
The lining of b, 3b, ...
3b, ...
Drives the shield machine 2 to build the other tunnel Tb. At this time, the retractable tip blades 10a, 20a of the cutter devices 10, 20 are extended so that the cutter devices 10, 20 can excavate a tunnel having at least the same diameter as the skin plates 1a, 2a.

(ii) Next, as shown in FIG. 2, the shield machine 1 and the shield machine 2 are stopped at a predetermined interval (a distance of about 10 m in this embodiment) 1 before the end of the tunnel excavation. Then, horizontal boring is performed by the steel pipe 29 from the inside of the first shield machine 1 toward the receiving portion 28 provided on the front surface of the second shield machine 2 and having a water blocking function, and the steel pipe 29 is moved to the second shield machine. Insert into the inside of 2. Then, the laser sighting device 30 is installed at one end (inside the first shield machine 1) of the steel pipe 29 installed between the first and second shield machines 1 and 2, and at the other end (second The light receiver 31 is installed in the shield machine 2), and the laser light oscillated from the laser sighting device 30 is supplied to the steel tube 2
The relative position between the first shield machine 1 and the second shield machine 2 is confirmed by measuring the positional relationship between the oscillation point, the light receiving point, and the reference line of the shield machine by receiving light through the light receiver 31 through 9 To do.

In addition, the method of confirming the relative position between shield machines is
It is not limited to a method of passing a laser through the steel pipe 29, and a level line of sight is passed through the steel pipe 29.
Any method can be used as long as the relative position can be confirmed.

(iii) When the relative positions of the first and second shield machines 1 and 2 are confirmed, the steel pipe 29 is pulled out and removed, and the through hole of the steel pipe 29 is closed, and then the first shield machine 1 is removed. A predetermined error range with the second shield machine 2 (in the present embodiment, the parallel movement error of the central axes of the shield machines 1 and 2 is within 5 cm in the vertical and horizontal directions, and the angle formed by the central axes is 1).
The second shield machine 2 is propelled so as to face each other within a distance l left between the shield machines while facing each other so as to face each other (within °), and the first shield machine 1 and the ground Gi of 30 cm to 1 m are struck. Leave them to face each other.

As a result of measuring the relative positions of the first and second shield machines 1 and 2 in this step, the error is large, and the direction of the second shield machine 2 when a sudden direction correction is necessary. As a control means, the tip blade 20a of the cutter device 20 of the shield machine 2 has a structure capable of projecting by a predetermined length from the outer diameter of the skin plate 2a, and the outer peripheral portion of the skin plate 2a is dug into the outer blade of the same. By injecting mud material, the outer peripheral portion of the skin plate 2a is covered with mud, and then the mud on the side where the shield machine 2 is to be moved is sucked by a pump (not shown) provided in the skin plate 2a, The direction of the shield machine 2 is corrected by discharging the skin plate 2a at a high pressure to the outside of the skin plate 2a on the opposite side and moving the skin plate 2a. According to this, it is possible to correct the direction, which can only be done while proceeding with normal direction control, while the shield machine 2 is stopped, and it is possible to perform a large direction control in a short distance and to perform parallel direction to the central axis. You can move.

Further, the skin plate 2a is divided into front and rear parts, and a simple center bending mechanism (not shown) in which they are connected by a bolt via a turnbuckle is adopted, or the segment 3b to be assembled is made of thin steel. By using a thin segment (not shown) made of a product, the direction of the shield machine 2 can be rapidly corrected, and the error in the relative position with respect to the first shield machine 1 can be reduced.

(iv) Next, replace the second shield machine 2 with the first shield machine 1
Against this, the relative position is corrected to be within a predetermined error range and brought closer to the ground, and then a natural ground G of about 30 cm to 1 m
Face i, leaving i. Then, as shown in FIG. 3, while rotating the cutter device 10 of the first shield machine 1 and the cutter device 20 of the second shield machine 2 in mutually opposite directions, the injection pipes 17 and 27 with respect to the cutting face are rotated. To inject mud to replace earth and sand and gravel of the ground Gi left between the shield machines 1 and 2 with mud. By doing so, there are no obstacles such as gravel between the shield machines 1 and 2, and the work of bringing the shield machines 1 and 2 closer to each other or penetrating the penetrating ring 13 into the penetrating chamber 23 is performed smoothly in the following steps. And it becomes possible to perform reliably.

(v) Next, as shown in FIG. 4, the tip blades 10a of the cutter devices 10 and 20 of the first and second shield machines 1 and 2,
After the tips of the cutter devices 10 and 20 are made slightly shorter than the inner diameters of the inner cylinders 12 and 22, respectively, by shrinking the 20a, the shaft portion 15 is placed behind the first shield machine 1 (right side with respect to the paper surface). Further, by sliding the shaft portion 25 to the rear of the second shield machine 2 (on the left side with respect to the paper surface), the cutter device 10 is stored inside the inner cylinder 12, and the cutter device 20 is moved to the inner cylinder 22. Store inside.

(vi) When the cutter devices 10 and 20 are housed in the inner cylinders 12 and 22, the propulsion jack 26 is driven to drive the second device.
After further advancing the shield machine 2 of the first shield machine 2 so that the clearance between the shield machine 2 and the first shield machine 1 is close to 10 cm or less, as shown in FIG. By sliding 13 along the axis, it is sequentially inserted into the penetration chamber 23 of the second shield machine 2 and allowed to penetrate. At that time, before the penetration ring 13 is penetrated into the penetration chamber 23, a thermoplastic filler provided so as not to be clogged with dirt, gravel and the like in the penetration chamber 23 when the shield machine 2 is propelled by the heating means. By heating and softening, the penetration of the penetration ring 13 is performed smoothly. After the penetration ring 13 is penetrated, the thermoplastic filler is hardened again by natural cooling, and the water blocking effect of the penetration portion can be enhanced.

It should be noted that the method of penetrating the penetrating ring 13 into the penetrating chamber 23 is not limited to the method of the above-described embodiment, and the inside of the penetrating chamber 23 can be slid along the axial direction in a close contact state, A ring-shaped or divided ring-shaped piston member (not shown) is provided, and this piston member is reciprocally driven in the penetration chamber via a rod (not shown) by a jack (not shown) provided in the shield machine. The penetration room 2
Method to penetrate the penetration ring 13 after securing the space by discharging the earth and sand and gravel etc.
A high pressure jet nozzle (not shown) is provided at the tip of the penetration ring 13, and when the high pressure jet nozzle is inserted into the penetration chamber 23,
Penetration chamber 23 while ejecting a high-pressure jet from the nozzle
This is a method in which the sand and gravel inside are blown away and the penetration ring 13 is penetrated while ensuring the space inside the penetration chamber 23. When using these methods, a chemical solution is injected into the penetration chamber 23 by a predetermined method to stop the water.

Further, as a drive device for the penetration ring that moves the penetration ring 13 toward the penetration chamber 23, a dedicated push jack may be provided in the shield machine 1 from the beginning, and it may be driven by it. In this embodiment, the penetration ring 1 is driven when the penetration ring 13 is driven.
The center hole jacks 32, 32, 32 are fixed to the rods (not shown) fixed at the rear end portions of the rear end portion 3 at predetermined intervals in the circumferential direction at predetermined intervals in the circumferential direction in the skin plate 1a. ..Attached, which allows rod 3
Penetration ring 13 in sequence while adding 3, 33, ...
To be extruded. By using this device, the expensive push jack is not made disposable, and if the propelling jacks 16, 16, ... The length of the skin plate 1a can be shortened, the cost can be greatly reduced, and the direction control of the shield machine 1 can be facilitated.

(vii) After the penetration ring 13 penetrates into the penetration chamber 23 and covers the ground Gi of the joint left between the shield machines 1 and 2, the penetration ring 13 and the front portion 1b of the skin plates 1a and 2a are covered. , 2b to inject a chemical solution to sufficiently stop the water. Then, as shown in FIG. 6, the shield machines 1 and 2 are disassembled with the skin plates 1a and 2a left, and then the penetration ring 13 and the inner cylinders 12 and 22 are integrated by welding without a gap. plate 1a, the inner side of the 2a, so that the tunnel Ta, hitting設面flush concrete C in the secondary lining subjected to Tb, performs lining of the joint by pouring a concrete C _S .

Therefore, by using this method, the relative position between the first shield machine 1 and the second shield machine 2 is accurately confirmed before joining in the ground, and then the second shield machine 2 is moved to a predetermined error range. It is possible to reliably approach the first shield machine 1 inside, to securely penetrate the penetration ring 13 into the penetration chamber 23, and to bond the shield machines 1 and 2, and to skin the ground Gi of the joint part. It can be completely covered with the plates 1a and 2a and the penetration ring 13, and the tunnel connection work can be performed safely and reliably without using an auxiliary construction method such as a freezing construction method, which greatly shortens the construction period and greatly reduces the construction cost. Reductions can be realized.

In addition, in the said Example, when approaching the shield machines 1 and 2, the 2nd shield machine 2 was approached, carrying out direction control, However, It is not restricted to that, and the 2nd shield machine 2 is stopped. Alternatively, the first shield machine 1 provided with predetermined equipment may be brought close thereto while performing direction control.

[Advantages of the Invention] As described above, the present invention has the first shield machine in which the penetration ring is housed between the outer cylinder and the inner cylinder, and the penetration chamber constituted by the outer cylinder and the inner cylinder. A tunnel is excavated from both sides with the second shield machine as a set, the shield machine is stopped at a predetermined interval before the tunnel excavation process is completed, and horizontal bowling with a steel pipe is performed between the shield machines to determine the relative position. After checking, propel one shield machine while correcting the direction, then cover the ground of the tunnel junction left between the shield machines by penetrating the penetration ring into the penetration chamber, and then remove the skin plate. Since the shield machine was dismantled while leaving it, the tunnel was joined, then concrete was placed on the inner surface of the skin plate to cover the wall surface of the joint, The relative position of two shield machines excavated from both sides can be accurately confirmed in the ground, and they can be surely brought close to each other within a predetermined dimensional error range. Tunnel penetration is achieved by penetrating the penetration ring into the penetration chamber. You can completely cover the ground near the part with a skin plate,
Secures soil retention and water stop against the water stop pressure that acts on the joint of the shield machine, and can safely perform the joint work without using auxiliary construction methods such as freezing construction method and underground tunnel joint work The required construction period can be greatly shortened and the construction cost can be greatly reduced.

[Brief description of drawings]

1 to 6 are for explaining an embodiment of the underground joining method for the shield tunnel of the present invention,
Fig. 1 is a side sectional view of a tunnel constructed by excavating the ground by two shield machines from both sides.
The figure shows a cross-sectional side view of the tunnel showing the shield machines being stopped at a predetermined interval and checking their relative positions. Figure 3 shows the ground improvement of the ground between the shield machines. Fig. 4 is a side sectional view of the tunnel shown in Fig. 4, Fig. 4 is a sectional side view of the tunnel showing the cutter device of the shield machine contracted, and Fig. 5 shows the shield machine connected by a penetration ring to cover the ground. FIG. 6 is a side sectional view of the tunnel showing a state where the shield machine is disassembled and the tunnel is penetrated to complete the tunnel machine, and FIG. 7 is a side sectional view of the tunnel showing the conventional technique. G ... Ground, Gi ... Tunnel junction ground, Ta, Tb
...... Tunnel, 1 ... First shield machine, 2 ... Second shield machine, 1a, 2a ... Skin plate, 1b, 2
b ... Skin plate tip, 1c, 2c ... Shield tail, 3a, 3b ... Segment, 10, 20 ...
Cutter device, 10a, 20a ... Tip blades 11, 21, ...
... outer cylinder, 12,22 ... inner cylinder, 13 ... penetration ring, 1
6,26 …… Propulsion jack, 23 …… Penetration room, 29 ……
Steel pipe, _{C s, C} ...... concrete.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Miyazawa 2-16-1 Kyobashi, Chuo-ku, Tokyo Within Shimizu Construction Co., Ltd. (72) Inventor Akihiro Honda 2-16-1 Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Hiroyuki Kubo 2-161-1 Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Hisao Arai 2-16-1 Kyobashi, Chuo-ku, Tokyo Shimizu Ken Incorporated Co., Ltd. (72) Inventor Nobuhiro Tsuchiya 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Corporation Incorporated (72) Inventor Takao Nakagawa 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction In-house (72) Inventor Yoshihiko Shimizu 2-16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Yoji Toyoji 2-16-1 Kyobashi, Chuo-ku, Tokyo Shimizu Construction Stock Association The inner

Claims (1)

[Claims] 1. A tunnel to be built by using two shield excavators that excavate the ground by a cutter device provided in the front part and propel the ground while assembling the segments for the primary lining inside. This is a method of underground joining of shield tunnels when tunnels are completed by excavating tunnels from both ends and joining them in the middle, and the tip of the skin plate consists of an outer cylinder and an inner cylinder. A first shield machine having a heavy weight and a penetrating ring housed between the outer cylinder and the inner cylinder, and an outer cylinder and an inner cylinder in which the tip end of the skin plate has the same diameter as that of the first shield machine. A tunnel is excavated from both sides with a second shield machine having a penetrating chamber configured by being double-formed by and the first seal before completion of the tunnel excavation process. The machine and the second shield machine are stopped at a predetermined interval, and horizontal bowling with a steel pipe is performed between the first shield machine and the second shield machine to confirm the relative position. Propulsing one shield machine to the position immediately before the other shield machine while controlling the direction, and then sliding the penetration ring of the first shield machine forward to penetrate into the penetration chamber of the second shield machine. After covering the ground of the tunnel junction left between the first and second shield machines by, dismantling the shield machine while leaving the skin plates of the first and second shield machines, and constructing the tunnel. An underground joining method for a shield tunnel, which comprises joining and then placing concrete on the inner surface of the skin plate to cover the wall surface of the joining portion.