JP2017145641A - Reinforcement method of existing tunnel and tunnel reinforcement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcement method of an existing tunnel and a tunnel reinforcement device for early providing the excellent tension reinforcement effect and the sure water cutoff effect.SOLUTION: A reinforcement method of an existing tunnel and a tunnel reinforcement device used therefor, comprises a boring process of excavating the periphery of an existing tunnel 1 and covering the periphery of the existing tunnel 1 by a shield machine 2, an assembly process of forming a new segment ring 33 for covering an outer surface of the existing tunnel 1 in the shield machine 2 and a filling process of filing a filler in a clearance between the outer surface of the existing tunnel 1 and the new segment ring 33 and injecting a back-filling material into a clearance between an outer surface of the new segment ring 33 and the natural ground.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for reinforcing an existing tunnel and a tunnel reinforcing device.

In order to reinforce an old tunnel, it is common to reinforce it from the inside of the tunnel. For example, there are a reinforcing method in which inner concrete is placed along the inner wall surface of the tunnel, a reinforcing method in which a fiber sheet, a steel plate, or the like is attached. In addition, the ground around the tunnel may be reinforced by improving the ground from inside the tunnel or from the ground.
However, if the tunnel lining is reinforced from within the tunnel, the tunnel interior becomes narrower and the function of the tunnel may be degraded. Also, when performing reinforcement work in the tunnel, it is necessary to stop using the tunnel. In addition, ground improvement from the ground takes work and increases construction costs depending on the depth of the tunnel. Furthermore, ground improvement from the ground is limited to the case where a working space can be secured on the ground.

  Therefore, the present applicant excavated around the existing tunnel by towing a hollow excavator having a hollow portion of the same extent as the outer periphery of the existing tunnel with an auxiliary shield excavator attached to the outside of the hollow excavator. A method for reinforcing existing tunnels has been developed (see Patent Document 1). A space formed around the existing tunnel by excavation is filled with a filler that develops a predetermined strength after curing, such as grout, mortar, or concrete.

JP 2002-021472 A

The method for reinforcing an existing tunnel described in Patent Document 1 takes time until the strength of the filler to be filled between the natural ground and the existing tunnel is developed, and further, the reinforcing method has a small tensile reinforcing effect. Moreover, since the structure is reinforced with a filler placed between the natural ground and the existing tunnel, there is a possibility that sufficient water stoppage may not be ensured depending on the natural ground condition. Therefore, there has been a demand for a reinforcing method that is expected to have a tensile reinforcement effect more quickly and that has a better water-stopping property.
From such a viewpoint, an object of the present invention is to propose an existing tunnel reinforcement method and a tunnel reinforcement device that can obtain a more excellent tensile reinforcement effect and a reliable water stop effect at an early stage.

A method for reinforcing an existing tunnel according to the present invention for solving the above-described problems includes an excavation step of excavating the periphery of the existing tunnel and covering the periphery of the existing tunnel with a shield machine, and a new segment ring that covers the outer surface of the existing tunnel. An assembly process formed in the shield machine, and filling that fills the gap between the outer surface of the existing tunnel and the new segment ring and injects a backfill material into the gap between the outer surface of the new segment ring and the ground And a process.
According to such a method for reinforcing an existing tunnel, the existing tunnel is reinforced by assembling a new segment ring around the outer periphery of the existing tunnel, so that a reinforcing effect (excellent tensile effect and water stop effect) can be obtained at an early stage. Moreover, since reinforcement is performed from the outside of the tunnel, it is not necessary to stop the use of the existing tunnel.
By forming the auxiliary tunnel along the existing tunnel in the excavation process, it is possible to transport the reinforcing segment of the new segment ring assembled in the assembly process.
By assembling while moving the reinforcing segment along the outer periphery of the existing tunnel in the assembling step, it is possible to form a new segment ring in a limited space.

Further, the tunnel reinforcement device of the present invention is provided in a cylindrical main body having a hollow portion through which an existing tunnel can be inserted, excavation means provided at a tip of the main body, and an inner space of the main body. Providing means, water stopping means provided on the front end side and rear end side of the inner space of the main body, and an auxiliary shield machine attached to the outside of the main body, comprising: Insertion holes are formed in the main body part and the auxiliary shield machine, respectively, at the face side end of the auxiliary shield machine so that the reinforcing segments to be assembled on the outer periphery can be carried into the main body part from the auxiliary shield machine. It is characterized by being.
By using such a tunnel reinforcement device, an existing tunnel can be reinforced from the outside. Therefore, it is not necessary to stop the use of existing tunnels in service.
By providing a ring-shaped assembly guide that can rotate along the outer periphery of the existing tunnel, it is possible to form a new segment ring while rotating the reinforcing segment.
The main body includes a cylindrical front torso and a cylindrical rear tor that has a face-side end inserted in a rear part of the front torso, and the rear torso is connected to the front torso via a pulling jack. If the insertion hole is formed in the rear cylinder, the assembly of the new segment ring and the excavation of the outer periphery of the existing tunnel can be performed more safely.
In the case where the excavating means has a cutter portion that is rotatably provided along the outer periphery of the existing tunnel, and a rotational mechanism is provided to the auxiliary shield machine to apply a rotational force to the cutter portion. As a result, the configuration of the main body is simplified, and as a result, the excavation sectional area around the existing tunnel can be reduced.

  According to the method and apparatus for reinforcing an existing tunnel of the present invention, it is possible to construct a reinforcing structure for an existing tunnel that can obtain a superior tensile effect and a reliable water stop effect at an early stage.

It is a longitudinal section showing a tunnel reinforcement device concerning an embodiment of the present invention. It is a front view which shows the tunnel reinforcement apparatus of FIG. It is a longitudinal section which shows a reinforcement structure. It is an enlarged vertical sectional view showing a tunnel reinforcement device, (a) is when excavating, (b) is during segment assembly preparation, and (c) is during segment assembly. It is an expanded sectional view which shows a part of tunnel reinforcement apparatus of FIG. It is a schematic diagram which shows a rotation mechanism. (A) The partial perspective view which shows the assembly guide, (b) is the partial perspective view which shows the assembly guide which concerns on another form. (A) And (b) is an expanded sectional view which shows a part of tunnel reinforcement apparatus at the time of segment assembly. It is a perspective view which shows a segment assembly condition typically. It is an enlarged vertical sectional view showing a filling process.

In this embodiment, as shown in FIGS. 1 and 2, an existing shield tunnel (hereinafter referred to as “existing tunnel”) 1 formed by combining segments 11 is segmented using a tunnel reinforcement device 2. The case where it reinforces from the outer surface of 11 is demonstrated.
The existing tunnel 1 is formed in a cylindrical shape. Note that the existing tunnel 1 is not necessarily a shield tunnel, and may be a mountain tunnel, for example.
As shown in FIG. 3, the reinforcing structure 3 of the existing tunnel 1 includes a reinforcing cover 30 that covers the outer surface of the existing tunnel 1, and a filler 31 that is filled in a gap between the reinforcing cover 30 and the existing tunnel 1. Has been. The reinforcing lining 30 is formed in a cylindrical shape by connecting a new segment ring 33 formed by combining a plurality of reinforcing segments 32 into the ground.

As shown in FIG. 1, the tunnel reinforcement device 2 is a device that digs around the existing tunnel 1 and forms a reinforcement structure 3 (reinforcement lining 30) that covers the outer surface of the existing tunnel 1.
The tunnel reinforcement device 2 of the present embodiment is a so-called shield machine that has a cylindrical shape so as to cover the outer surface of the existing tunnel 1. The tunnel reinforcement device 2 includes a main body 4, an auxiliary shield machine 5, an assembly guide 6, excavation means 7, a water stop means 8, and a propulsion means 9.

The main body 4 is a cylindrical member having a hollow portion through which the existing tunnel 1 can be inserted.
As shown in FIG. 4, the main body 4 of the present embodiment includes a cylindrical front cylinder 41 and a rear cylinder 42.
The front cylinder 41 is made of a cylindrical steel pipe and has an inner diameter equal to or larger than the outer diameter of the rear cylinder 42.
The rear trunk 42 is made of a cylindrical steel pipe, and the face side end portion of the rear trunk 42 is inserted into the rear part of the front trunk 41. Further, the rear cylinder 42 is provided so as to be able to advance and retreat with respect to the front cylinder 41 via a pull jack 43.
As shown in FIG. 5, an insertion hole 44 is formed in the rear body 42. The insertion hole 44 is formed at a position corresponding to the insertion hole 54 of the auxiliary shield machine 5 attached to the outer surface of the main body 4. The insertion hole 44 has a shape that allows the reinforcement segment 32 to be inserted therethrough.
The hollow part of the main body 4 (rear trunk 42) has a shape larger than the outer shape of the existing tunnel 1. That is, a gap (space) is formed between the outer surface of the existing tunnel 1 and the inner surface of the main body 4.

An auxiliary shield machine 5 is attached to the outer surface of the main body 4 as shown in FIG.
In the present embodiment, four auxiliary shield machines 5 are arranged at equal intervals with respect to the outer periphery of the main body 4. In addition, the number and arrangement | positioning of the auxiliary shield machine 5 are not limited.
As shown in FIG. 1, a cutter head 51 is provided at the tip of the auxiliary shield machine 5. The cutter head 51 includes a plurality of cutter bits (not shown), and cuts natural ground by rotating. The cutter head 51 is rotated by the power of a motor (not shown) built in the auxiliary shield machine 5. The cutter head 51 of this embodiment is a so-called spoke type. The configuration of the cutter head 51 is not limited and may be, for example, a face plate shape. The auxiliary shield machine 5 may be provided with other cutting means instead of the cutter head 51.
A drive gear 52 is provided behind the cutter head 51. The drive gear 52 rotates together with the cutter head 51. The drive gear 52 is a rotation mechanism that applies a rotational force to the excavating means 7 (gear 73) provided at the tip of the main body 4 (see FIG. 6).

A plurality of steel pipes 53 are continuously provided along the axial direction of the existing tunnel 1 behind the auxiliary shield machine 5 (wellhead side). The steel pipe 53 is connected from the auxiliary shield machine 5 to the wellhead and forms an auxiliary tunnel 50. That is, the auxiliary shield machine 5 is an excavator for forming the auxiliary tunnel 50 along the existing tunnel 1. The lining of the auxiliary tunnel 50 is not limited to the steel pipe 53, and may be formed by a concrete segment, for example.
The steel pipe 53 is continuously provided in the excavation hole drilled by the auxiliary shield machine 5. Inside the steel pipe 53, an unillustrated earthing pipe, electric wires and hydraulic pipes necessary for driving the tunnel reinforcement device 2 and the auxiliary shield machine 5 are disposed. The steel pipe 53 has an inner diameter necessary for transporting the reinforcing segment 32. In the present embodiment, the reinforcing segment 32 is transported by the battery car 55 (see FIG. 5) that travels in the steel pipe 53 (auxiliary tunnel 50).

  As shown in FIG. 5, the auxiliary shield machine 5 is formed with an insertion hole 54 corresponding to the position of the insertion hole 44 of the main body 4 (rear body 42). The insertion hole 54 has a shape that allows the reinforcement segment 32 to be inserted therethrough. That is, the reinforcing segment 32 is transported to the vicinity of the face using the auxiliary tunnel 50, and then the main body portion 4 (rear trunk 42) through the insertion hole 54 of the auxiliary shield machine 5 and the insertion hole 44 of the rear trunk 42. It is carried into the inner space.

An assembly guide 6 is provided in the inner space of the main body 4 (rear barrel 42).
The assembly guide 6 is a device for assembling the reinforcing segment 32 transported via the auxiliary shield machine 5, and as shown in FIG. 7A, a guide body 61, an axial guide 62, and a circumferential guide 63. , Segment holding means 64 and driving means 65 are provided. The configuration of the assembly guide 6 is not limited.

The guide main body 61 is a ring-shaped member provided along the inner surface of the rear barrel 42. The guide main body 61 includes a fixed portion 66 and a rotating portion 67 provided so as to be rotatable along the outer periphery of the existing tunnel 1 (that is, movable in the circumferential direction of the existing tunnel 1).
As shown in FIG. 7A, the fixing portion 66 is a cylindrical member disposed inside the rear trunk 42. On the surface of the fixed portion 66, a concave groove that can accommodate the rotating portion 67 is formed. The inner diameter of the fixed portion 66 is larger than the outer diameter of the existing tunnel 1, and the outer diameter of the fixed portion 66 is smaller than the inner diameter of the new segment ring 33. A gap larger than the thickness of the segment ring 33 (segment 32) is formed between the outer peripheral surface of the fixed portion 66 and the inner peripheral surface of the rear barrel 42. The fixing portion 66 is fixed to the rear barrel 42 via a guide fixing member 68. The guide fixing member 68 has one end fixed to the rear barrel 42 and the other end fixed to the fixing portion 66 (see FIG. 4A). The guide fixing member 68 of the present embodiment is a columnar member, and is erected on the face side end of the fixing portion 66. The shape of the guide fixing member 68 and the installation interval are not limited.

  The rotating part 67 is provided on the surface of the fixed part 66 (the ground surface). The outer diameter of the rotating part 67 is smaller than the inner diameter of the new segment ring 33. Further, a gap larger than the thickness of the segment ring 33 (segment 32) is formed between the outer peripheral surface of the rotating portion 67 and the inner peripheral surface of the rear barrel 42. As shown in FIG. 7A, the rotating part 67 is rotated by the power of the driving means 65 provided in the fixed part 65. In the present embodiment, a motor is used as the driving means 65. Since the rotating portion 67 is formed with a gear 67a that meshes with the gear 65a of the driving means 65, the power of the driving means 65 is transmitted by being transmitted through the gears 65a and 67a. In addition, since the lubricant is interposed between the fixed portion 66 and the rotating portion 67, the rotation of the rotating portion 67 is not hindered by the frictional resistance between the fixed portion 66 and the rotating portion 67.

  The driving means 65 is not limited to a motor. For example, as shown in FIG. 7B, a winch may be used as the driving means 65. When a winch is used as the driving means 65, a wire 67b is used instead of the gear 67a. The driving means 65 (winch) is fixed to each of the fixed portion 66 and the rotating portion 67, and one wire 67b is wound around both the driving means 65. While the wire 67b is rewound by one driving means 65, the rotating portion 67 is rotated by unwinding the wire 67b from the other driving means 65.

The rotating part 67 is provided with an axial guide 62 and a circumferential guide 63.
The axial guide 62 is a member for preventing displacement of the reinforcing segment 32 placed on the guide body 61, and is fixed to the face side end of the rotating portion 67. The axial guide 62 of the present embodiment is formed with an insertion member (not shown) that can be inserted into the inter-ring joint (female joint) of the reinforcing segment 32. The reinforcing segment 32 is fixed by inserting the insertion member of the axial guide 62 into the inter-ring joint of the reinforcing segment 32.

The circumferential guide 63 is a member for holding the circumferential end of the reinforcing segment 32 placed on the guide body 61. The circumferential guide 63 holds the first reinforcing segment 32 among the reinforcing segments 32 that are carried in when forming the new segment ring 33, thereby preventing the reinforcing segment 32 from sliding down along the guide body 61. . As shown in FIG. 5, the circumferential guide 63 of the present embodiment is formed with an insertion member 63 a that can be inserted into the inter-segment joint (female joint) of the reinforcing segment 32. As shown in FIG. 5, the reinforcing segment 32 is fixed by inserting the insertion member 63 a of the circumferential guide 63 into the inter-segment joint of the reinforcing segment 32.
The configurations of the axial guide 62 and the circumferential guide 63 are not limited.

As shown in FIG. 7A, the rotating unit 67 is further provided with a segment holding unit 64.
The segment holding means 64 holds the reinforcing segment 32 placed on the guide body 61. The segment holding means 64 of the present embodiment includes an electromagnet, and holds the reinforcing segment 32 by magnetic force by energizing the electromagnet. A plurality of segment holding means 64 are provided with an interval equal to the circumferential width of each reinforcing segment 32 with respect to the circumferential direction of the rotating portion 67. The configuration of the segment holding means 64 is not limited. For example, when the reinforcing segment 32 is a segment other than the steel segment, the segment holding means 64 is an air vacuum type, and holds the reinforcing segment 32 by a suction force. Further, the arrangement (arrangement pitch or the like) of the segment holding means 64 is not limited.

As shown in FIGS. 1 and 2, the excavating means 7 is installed at the tip of the main body 4. The excavation means 7 includes a cutter part (cutter head) 71 that is rotatably provided around the existing tunnel 1 and a plurality of cutter bits 72, 72,. . In addition, the structure of the excavation means 7 is not limited.
As shown in FIGS. 1 and 6, a gear 73 that meshes with the drive gear 52 is formed at the rear portion of the cutter portion 71. That is, the cutter unit 71 is rotated by the power transmitted via the drive gear 52 as the cutter head 51 of the auxiliary shield machine 5 rotates. When the cutter unit 71 rotates, the ground around the existing tunnel 1 is cut.
The excavation means 7 further includes a cleaning means 74. As shown in FIG. 4A, the cleaning means 74 is composed of a plurality of injection nozzles, and injects high-pressure water WJ onto the outer surface of the existing tunnel 1 exposed by excavation of natural ground. By doing so, earth and sand and backfill material adhering to the outer surface of the existing tunnel 1 are removed. The cleaning means 74 may be a wire brush.

As shown in FIG. 1, the water stop means 8 is provided on each of the front end side and the rear end side of the inner space of the main body 4.
The water stop means 8 of the present embodiment includes head seals 81 and 82 provided at the front end of the main body 4, a first tail seal 83 provided at the rear end of the main body 4, and the assembly guide 6. And a second tail seal 84 provided at the end. In addition, what is necessary is just to determine suitably the number and arrangement | positioning of the water stop means 8 (packing) according to a water pressure.
The head seals 81 and 82 provided at the distal end of the main body 4 close the space formed between the existing tunnel 1 and the main body 4. In the present embodiment, a first head seal 81 and a second head seal 82 are provided at the front end portion of the front cylinder 41 and the front end portion of the rear cylinder 42, respectively.

The first head seal 81 is provided around the inner surface of the front barrel 41. The first head seal 81 is made of an annular rubber plate provided so as to be able to advance and retract in the center direction of the front barrel 41. As shown in FIG. 4B, when the first head seal 81 advances in the center direction of the front cylinder 41, the first head seal 81 comes into close contact with the outer surface of the existing tunnel 1, and the front cylinder 41 and the existing tunnel 1 are connected. The gap is closed. On the other hand, as shown in FIG. 4A, when the first head seal 81 is retracted in the direction of the front barrel 41, the gap between the front barrel 41 and the outer surface of the existing tunnel 1 is released. In addition, the material which comprises the 1st head seal 81 is not limited, For example, an annular tube and a lip seal may be sufficient. When a tube is used as the first head seal 81, the first head seal 81 is inflated by press-fitting a fluid into the tube and brought into close contact with the existing tunnel 1 on the outer surface.
The second head seal 82 is provided around the inner surface of the rear barrel 42. Since the other details of the second head seal 82 are the same as those of the first head seal 81, detailed description thereof is omitted.

  The first tail seal 83 closes the space formed between the main body 4 and the reinforcing cover 30 at the rear end of the main body 4. The first tail seal 83 is configured by fixing the wire brush immersed in the grease to the inner surface of the rear barrel 42 and bringing the tip of the wire brush into close contact with the outer surface of the new segment ring 33. In the first tail seal 83, the base end side of the wire brush (the portion fixed to the rear barrel 42) is positioned on the front side (the side opposite to the vertical shaft) from the tip side (the portion in contact with the new segment ring 33). Thus, it is arranged in an inclined state. In the present embodiment, two stages of wire brushes are arranged along the tunnel axis direction, but the number of wire brushes is not limited. Further, the first tail seal 83 is not necessarily a wire brush, and may be formed of, for example, an annular urethane rubber.

  The second tail seal 84 closes a space formed between the assembly guide 6 and the existing tunnel 1 at the rear end portion of the assembly guide 6. The second tail seal 84 is configured by fixing the wire brush dipped in grease to the inner surface of the assembly guide 6 and bringing the tip of the wire brush into close contact with the outer surface of the existing tunnel 1. As for the 2nd tail seal 84, the base end side (part fixed to the assembly guide 6) of a wire brush is located ahead (front side opposite to a shaft) rather than the front end side (part which touches the existing tunnel 1). Are arranged in an inclined state. In the present embodiment, two stages of wire brushes are arranged along the tunnel axis direction, but the number of wire brushes is not limited. Further, the second tail seal 84 is not necessarily a wire brush, and may be constituted by, for example, an annular urethane rubber.

The propulsion means 9 is provided in the inner space of the main body 4.
The propulsion means 9 is disposed behind (at the wellhead side) the first head seal 81 of the front barrel 41. The propulsion means 9 is a so-called propulsion jack, and applies thrust to the front barrel 41 (main body portion 4) by extending in the tunnel axis direction. The rear end (well end side end) of the propulsion means 9 is in contact with the front surface (face side end face) of the new segment ring 33. The propulsion means 9 moves the main body 4 forward by taking a reaction force from the new segment ring 33 (reinforcing lining 30). The propulsion means 9 may take a reaction force from the auxiliary shield machine 5 (auxiliary tunnel 50), or may react from both the new segment ring 33 (reinforcement lining 30) and the auxiliary shield machine 5 (auxiliary tunnel 50). You may take power.

Next, the reinforcement method of the existing tunnel using the tunnel reinforcement apparatus 2 of this embodiment is demonstrated.
The existing tunnel reinforcement method includes an excavation process, an assembly process, and a filling process.
The excavation process is a process of excavating the surroundings of the existing tunnel 1 without cutting. The excavation process is performed using the tunnel reinforcement device 2. In the present embodiment, as shown in FIG. 4A, the surroundings of the existing tunnel 1 are covered with the main body 4 by cutting the ground by the excavating means 7 and moving the main body 4 forward by the propulsion means 9. During excavation, the gap between the existing tunnel 1 and the main body 4 is closed by the second head seal 82.
In the excavation process, the auxiliary tunnel 50 is formed as the excavation means 7 cuts the natural ground. The auxiliary tunnel 50 is formed by drilling a natural ground with the auxiliary shield machine 5 and connecting a steel pipe 53 continuously. The residual soil generated by the excavation process is transported through the auxiliary tunnel 50 and carried out of the mine.

  When the predetermined extension is dug, as shown in FIG. 4B, the rear barrel 42 is advanced using the pull jack 43 (drawn toward the front barrel 41) to secure a space for installing the reinforcing segment 32. At this time, the second head seal 82 is accommodated, and the first head seal 81 closes the gap between the existing tunnel 1 and the main body 4.

The assembly process is a process of forming a reinforcing cover 30 that covers the outer surface of the existing tunnel 1.
The reinforcing cover 30 is formed by assembling the reinforcing segments 32 in the tunnel reinforcing device 4 to form the new segment ring 33 and then joining the new segment ring 33 to the existing portion of the reinforcing cover 30.

In the assembly process, first, as shown in FIG. 5, the reinforcing segment 32 transported in the auxiliary tunnel 50 is placed on the assembly guide 6 through the insertion holes 44 and 54. The reinforcing segment 32 is held via an axial guide 62, a circumferential guide 63, and a segment holding means 64, as shown in FIG. Next, the assembly guide 6 (rotating part 67) is rotated to move the reinforcing segment 32, and then a new reinforcing segment 32 is carried in. The newly loaded reinforcing segment 32 is held via the axial guide 62, the circumferential guide 63 and the segment holding means 64, and is connected to the existing reinforcing segment 32 in the circumferential direction (FIGS. 8A and 8B). )reference). The reinforcing segments 32 are joined together by a so-called one-touch joint. The new segment ring 33 is formed by repeating the same operation.
When the new segment ring 33 is formed, as shown in FIG. 4C, the new segment ring 33 is pushed behind the tunnel reinforcing device 2 (wellhead side) by the propulsion means 9. As shown in FIG. 9, the new segment ring 33 is joined to the existing portion of the reinforcing lining 30. At this time, the new segment ring 33 is joined by a so-called one-touch joint.

As shown in FIG. 10, the filling step is a step of filling a filler 31 into the gap between the outer surface of the existing tunnel 1 and the reinforcing cover 30 (newly installed segment ring 33).
The filler 31 is injected behind the second tail seal 84. A cement-based material (mortar or cement milk) is used for the filler 31. In addition, the material which comprises the filler 31 is not limited.
Further, in the filling process, the backfill material 34 is placed in the gap between the outer surface of the reinforcing lining 30 (newly installed segment ring) and the natural ground simultaneously with the filling of the filling material 31 into the gap between the existing tunnel 1 and the reinforcing lining 30. inject. The backfill material 34 is injected behind the first tail seal 83. In addition, the material used for the backfill material 34 is not limited, and may be appropriately selected and used.

According to the method for reinforcing an existing tunnel and the tunnel reinforcement device 2 according to the present embodiment, the existing tunnel 1 is reinforced from the outer periphery without being cut, so that the site cannot be secured in the above-ground portion above the existing tunnel 1. Even if it exists, the existing tunnel 1 can be reinforced. That is, the lifetime of the existing tunnel 1 can be extended.
Further, since the reinforcement is performed from the outside of the existing tunnel 1, the existing tunnel 1 can be reinforced without stopping the use of the existing tunnel in service.
Further, since the new segment ring 33 is formed on the outer surface of the existing tunnel 1 to reinforce, the time required for curing can be shortened compared with the case of winding concrete, and the reinforcing effect (excellent tensile effect) can be shortened. And a water stop effect).

The reinforcing segment 32 can be transported by the auxiliary tunnel 50 formed along the existing tunnel 1. Moreover, maintenance of the tunnel reinforcement apparatus 2 by human power is possible using the auxiliary tunnel 50.
By assembling the reinforcing segment 32 while being moved (rotated) along the outer periphery of the existing tunnel 1 by the assembly guide 6, it is possible to form a new segment ring 33 in a limited space.
Since the new segment ring 33 is assembled while the reinforcing segment 32 is held by the assembly guide 6 (the axial guide 62, the circumferential guide 63 and the segment holding means 64), the reinforcing segment 32 is prevented from being displaced, and it is simple and safe. Can be done.

The main body portion 4 includes a front cylinder 41 and a rear cylinder 42, and the rear cylinder 42 is provided so as to be able to advance and retreat with respect to the front cylinder 41 via the pulling jack 43. The ring 33 can be formed safely in the main body 4.
By adopting a configuration in which the excavation means 7 is rotated by the rotation mechanism 52 disposed in the auxiliary shield machine 5, the configuration of the main body 4 is simplified, and consequently, the excavation cross-sectional area of the outer periphery of the existing tunnel 1 is reduced. Can do.

Since the reinforcement lining 30 (newly installed segment ring 33) is integrated with the segment 11 of the existing tunnel 1 via the filler 31, the existing tunnel 1 can be reliably reinforced.
Since the water stop means 8 is provided before and after the tunnel reinforcement device 2, groundwater and earth and sand are prevented from entering the gap between the existing tunnel 1 and the main body 4. Therefore, the construction of the reinforcing structure 3 is not hindered by groundwater or earth and sand.

The embodiment according to the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and the above-described components can be appropriately changed without departing from the spirit of the present invention.
For example, the auxiliary tunnel 50 may be formed as necessary.
The main body 4 does not necessarily have to have the front cylinder 41 and the rear cylinder 42, and may be formed by one cylindrical member. The main body 4 may be one in which three or more cylindrical members (front cylinder, rear cylinder, etc.) are connected.
The excavation means 7 may have drive means independent of the auxiliary shield machine 5.

1 Existing tunnel 2 Tunnel reinforcement device (shielding machine)
DESCRIPTION OF SYMBOLS 3 Reinforcement structure 31 Filler 32 Reinforcement segment 33 New segment ring 4 Main body part 41 Front trunk 42 Rear trunk 43 Pull jack 44 Insertion hole 5 Auxiliary shield machine 50 Auxiliary tunnel 52 Drive gear (rotation mechanism)
54 Insertion hole 6 Assembly guide 7 Excavation means 71 Cutter part 8 Water stop means 9 Propulsion means

Claims (7)

Excavating around the existing tunnel, and digging process to cover the surrounding of the existing tunnel with a shield machine,
An assembling step for forming a new segment ring in the shield machine to cover the outer surface of the existing tunnel;
Filling the gap between the outer surface of the existing tunnel and the new segment ring and filling the gap between the outer surface of the new segment ring and the ground, and a filling step. Reinforce the existing tunnel. In the excavation process, an auxiliary tunnel is formed along the existing tunnel,
2. The method of reinforcing an existing tunnel according to claim 1, wherein in the assembling step, a new segment ring is formed by assembling a plurality of reinforcing segments transported in the auxiliary tunnel.   The method for reinforcing an existing tunnel according to claim 2, wherein in the assembling step, the reinforcing segment is assembled while being moved along an outer periphery of the existing tunnel. A cylindrical main body having a hollow portion that can be inserted through an existing tunnel;
Excavation means installed at the tip of the main body,
Water stop means provided on the front end side and the rear end side of the inner space of the main body,
Propulsion means provided in the inner space of the main body,
An auxiliary shield machine attached to the outside of the main body, and a tunnel reinforcement device comprising:
An insertion hole is formed in each of the main body part and the auxiliary shield machine so that a reinforcing segment to be assembled around the outer periphery of the existing tunnel can be carried into the main body part from the auxiliary shield machine. A tunnel reinforcement device.   The tunnel reinforcement device according to claim 4, further comprising a ring-shaped assembly guide that is rotatable along an outer periphery of the existing tunnel. The main body portion includes a cylindrical front torso, and a cylindrical rear torso having a face side end inserted in a rear part of the front torso,
The rear torso is provided so as to be able to advance and retreat with respect to the front torso via a pull jack,
The tunnel reinforcement device according to claim 4 or 5, wherein the insertion hole is formed in the rear trunk. The excavation means has a cutter portion rotatable along the outer periphery of the existing tunnel;
The tunnel reinforcement device according to any one of claims 4 to 6, wherein the auxiliary shield machine is provided with a rotation mechanism that applies a rotational force to the cutter unit.

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