JP7609764B2 - Tunnel Boring Machine - Google Patents

Description

The present invention relates to a tunnel boring machine.

In a tunnel boring machine that builds a tunnel, a chamber is defined by the cutterhead and a partition wall behind it. The soil excavated by the cutterhead is retained in the chamber, and the pressure of the soil in the chamber is applied to the cutterhead, which suppresses the earth pressure and groundwater pressure at the face and stabilizes the face. The pressure of the soil in the chamber changes depending on the properties of the soil.

Patent Document 1 discloses a device that samples soil from the ground in front of a tunnel boring machine in order to understand the soil properties.

JP 2013-256843 A

If the soil properties are misjudged, the tunnel face may become unstable and ground deformation may occur. In particular, in low-cover tunnels, if ground deformation occurs around the tunnel boring machine, it may lead to ground subsidence. Therefore, it is important to accurately grasp the properties of the soil around the tunnel boring machine before stabilizing the tunnel face.

The sampling device described in Patent Document 1 cannot accurately grasp the properties of the soil around the tunnel boring machine.

The purpose of the present invention is to accurately grasp the properties of the soil around a tunnel boring machine.

The present invention is a tunnel boring machine that excavates the ground and constructs a tunnel, and includes a cylindrical body extending along the axial direction of the tunnel, an excavation section that is rotated at the front of the body, a partition wall that is provided within the body and arranged opposite the excavation section in the axial direction of the tunnel, a cutter chamber that is partitioned by the body, the excavation section, and the partition wall and into which the soil excavated by the excavation section flows, a sampling device that samples the soil, and a sampling work space that is provided along the body behind the cutter chamber and in which the sampling device is located. The sampling work space has a through hole that penetrates the body and can be opened and closed, and the sampling device can advance to the outside of the sampling work space and retreat into the sampling work space through the through hole in the body, and includes a sampling pipe that collects soil, and a drive device that rotates and drives the sampling pipe.

The present invention makes it possible to accurately grasp the properties of the soil around the tunnel boring machine.

1 is a schematic diagram of a shield tunneling machine according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the sampling device and the sampling work space from the front of the shield machine. FIG. 2 is a perspective view of the sampling device and the sampling workspace. FIG. This is a diagram showing the chronological order of the soil sampling procedure.

The following describes a tunnel boring machine according to an embodiment of the present invention with reference to the drawings.

In this embodiment, a shield machine 1 is described as a tunnel boring machine that excavates the ground (natural ground) to form an excavation hole and constructs a tunnel T by assembling segment rings 9 to cover the inner wall W of the excavation hole. Note that the present invention can also be applied to tunnel boring machines other than the shield machine 1.

First, the overall configuration of the shield tunneling machine 1 will be described with reference to Figure 1. In the following description, the tunnel face side, which is the direction in which the shield tunneling machine 1 advances, will be referred to as the "front," and the tunnel mouth side, which is the opposite direction to the front, will be referred to as the "rear."

The shield tunneling machine 1 comprises a skin plate 2 as a cylindrical body extending along the axial direction of the tunnel T and capable of supporting the inner wall W, a cutter head 3 as an excavation section that is rotated in front of the skin plate 2, a partition wall 4 provided within the skin plate 2 and positioned opposite the cutter head 3 in the axial direction of the tunnel T, a cutter chamber 5 into which the soil excavated by the cutter head 3 flows, and a sampling device 30 that samples the soil. Segment rings 9 are constructed sequentially on the rear side inside the skin plate 2 as the shield tunneling machine 1 advances.

A jack 7 is fixed to the skin plate 2. The jack 7 receives a reaction force from the segment ring 9 and propels the skin plate 2 forward, pressing the cutter head 3 against the ground. When the skin plate 2 is propelled and the segment ring 9 leaves the skin plate 2, backfill material (not shown) is filled between the outer periphery of the segment ring 9 and the inner wall W of the excavation hole.

The cutter head 3 is provided with multiple cutter bits 3a that protrude forward. When the cutter head 3 rotates while pressed against the ground, the ground is excavated by the cutter bits 3a to form an excavation hole. The soil excavated by the cutter head 3 is guided to the rear of the cutter head 3 through openings such as cutter slits (not shown) provided in the cutter head 3, and is retained in the cutter chamber 5.

The cutter chamber 5 is partitioned by a skin plate 2, a cutter head 3, and a partition wall 4. By filling the cutter chamber 5 with soil and applying the pressure of the soil in the cutter chamber 5 to the cutter head 3, the cutter head 3 can suppress the earth pressure and groundwater pressure at the face and stabilize the face. The amount of soil in the cutter chamber 5 is adjusted by being discharged by a screw conveyor (not shown).

A rotary joint 6 that passes through the bulkhead 4 is connected to the center of the cutter head 3. The rotary joint 6 is hollow, and pipes, cables, etc. are routed inside.

The shield tunneling machine 1 further includes an opposing wall 11 that is provided within the skin plate 2 and arranged opposite the partition wall 4 in the axial direction of the tunnel T, and a cutter drive unit 20 that is provided between the partition wall 4 and the opposing wall 11 and drives the cutter head 3 to rotate.

The cutter drive unit 20 has a swivel motor 21 as a drive source, a reduction mechanism 22 connected to the output shaft of the swivel motor 21, an annular cutter drum 23 connected to the reduction mechanism 22, and a number of connecting rods 24 connecting the cutter drum 23 and the cutter head 3. By driving the swivel motor 21, the cutter drum 23 rotates via the reduction mechanism 22, and the cutter head 3 rotates.

The shield machine 1 further includes an outer peripheral wall 26 that is disposed along the inner peripheral surface of the skin plate 2 and at a predetermined distance from the inner peripheral surface, and an inner peripheral wall 27 that is disposed inside the outer peripheral wall 26 and at a predetermined distance from the outer peripheral wall 26. The outer peripheral wall 26 and the inner peripheral wall 27 are disposed between the partition wall 4 and the opposing wall 11. The partition wall 4, the opposing wall 11, the outer peripheral wall 26, and the inner peripheral wall 27 define an annular space 28 in which the reduction mechanism 22 and/or the cutter drum 23 are housed. In addition, outside the space 28, the skin plate 2, the partition wall 4, the opposing wall 11, and the outer peripheral wall 26 define a sampling work space 31 in which a sampling device 30 is disposed. The sampling work space 31 is a space in which an operator can enter and perform work.

Next, the sampling device 30 and the sampling work space 31 will be described mainly with reference to Figures 2 to 4. Figure 2 is a schematic diagram of the sampling device 30 and the sampling work space 31 as viewed from the front of the shield tunneling machine 1, Figure 3 is a perspective view of the sampling device 30 and the sampling work space 31, and Figure 4 is a schematic diagram of the sealing mechanism 41. Figure 2 omits illustration of anything other than the sampling device 30 and the sampling work space 31, and Figure 3 omits illustration of the skin plate 2 and the partition wall 4.

As described above, the pressure of the soil in the cutter chamber 5 acts on the cutter head 3, which suppresses the earth pressure and groundwater pressure at the face and stabilizes the face. The pressure of the soil in the cutter chamber 5 varies depending on the properties of the soil, so it is necessary to accurately grasp the properties of the soil. In particular, in low-cover tunnels and large-section shield tunnels, if ground deformation occurs around the shield machine 1, it may lead to ground subsidence. Therefore, it is important to accurately grasp the properties of the soil around the shield machine 1 before stabilizing the face. In order to accurately grasp the properties of the surrounding soil, the shield machine 1 samples the soil around the shield machine 1 using a sampling device 30.

As shown in FIG. 2, in this embodiment, the sampling device 30 is disposed on top of the shield tunneling machine 1 to sample soil above the skin plate 2 in the annular sampling work space 31 defined by the skin plate 2, the partition wall 4, the opposing wall 11, and the outer peripheral wall 26. Specifically, two sampling devices 30 are provided symmetrically with respect to a vertical line X passing through the center of the shield tunneling machine 1. In this embodiment, the two sampling devices 30 are provided at positions 15 degrees on either side of the vertical line X. The two sampling devices 30 have the same configuration.

As shown in Figures 2 and 3, the sampling device 30 is placed in an upper sampling work space 31a, which is partitioned by two walls 32, 33 arranged at a predetermined distance in the circumferential direction of the annular sampling work space 31. The upper sampling work space 31a is located above the shield tunneling machine 1 in the annular sampling work space 31. An opening 33a is formed in the wall 33 to allow workers to enter and exit the upper sampling work space 31a. In Figure 3, only the upper sampling work space 31a is shown. Note that the walls 32, 33 are not essential components and can be omitted.

The shield tunneling machine 1 is provided with an earth pressure gauge 39 (see FIG. 1) that is an earth pressure measuring device that is provided on the skin plate 2 and measures the earth pressure acting on the skin plate 2. In this embodiment, the earth pressure gauge 39 is provided on the skin plate 2 that defines the upper sampling work space 31a, and measures the earth pressure acting on the outer peripheral surface of the upper part of the skin plate 2. In other words, the earth pressure gauge 39 can measure the earth pressure corresponding to the soil and sand collected by the sampling device 30.

The upper sampling work space 31a has a through hole 34 that penetrates the skin plate 2 and can be opened and closed. The sampling device 30 can move forward to the outside of the upper sampling work space 31a and backward into the upper sampling work space 31a through the through hole 34 of the skin plate 2, and has a sampling pipe 35 that collects soil and sand, an electric motor 50 as a drive device that rotates the sampling pipe 35, and a movement mechanism 51 that moves the sampling pipe 35 in the longitudinal direction (forward or backward).

The sampling pipe 35 is a hollow pipe that excavates the ground using a bit (not shown) attached to the end, and collects soil and sand inside.

As shown in FIG. 3, the sampling pipe 35 is connected to the output shaft of the electric motor 50. The moving mechanism 51 has a support 53 that supports the electric motor 50 and a gear mechanism 54 that moves the electric motor 50 along the support 53. The electric motor 50 is supported by the support 53 via a detachable spacer 55.

The gear mechanism 54 has a rack (not shown) formed along the longitudinal direction of the support 53, a pinion gear (not shown) that meshes with the rack, and a handle 54a that rotates the pinion gear. By rotating the handle 54a, the electric motor 50 moves along the support 53, and the sampling pipe 35 moves longitudinally (forward or backward). Note that an electric motor that rotates the pinion gear may be provided instead of the handle 54a.

The pillar 53 is disposed between the skin plate 2 and the outer peripheral wall 26. The lower end of the pillar 53 is supported by the outer peripheral wall 26 via a base 53a. The upper end 53b of the pillar 53 is supported by a receiving portion (not shown) formed in a hemispherical shape and provided on the inner peripheral surface of the skin plate 2. The pillar 53 receives a reaction force from the skin plate 2 and the outer peripheral wall 26 by a built-in jack, and is supported by being stretched between the skin plate 2 and the outer peripheral wall 26. This prevents the pillar 53 from bending.

As shown in Figures 3 and 4, the sampling device 30 further includes an on-off valve 40 that is provided in the skin plate 2 and opens and closes the through hole 34, and a sealing mechanism 41 that is connected to the on-off valve 40 and prevents water from entering the upper sampling work space 31a through the outside of the sampling pipe 35.

When sampling by the sampling device 30 begins, the on-off valve 40 opens to allow the sampling pipe 35 to advance through the through-hole 34, and when sampling ends, the sampling pipe 35 retreats through the through-hole 34 and then closes to block the inflow of soil and sand through the through-hole 34 into the upper sampling work space 31a. The on-off valve 40 can be opened and closed manually or electrically.

As shown in FIG. 4, the sealing mechanism 41 has a swivel mechanism 42 connected to the on-off valve 40 and a water stopper 43 connected to the swivel mechanism 42. The sampling pipe 35 can be inserted through the swivel mechanism 42 and the water stopper 43.

The swivel mechanism 42 has a fixed part 42a connected to the on-off valve 40, and a rotating part 42b rotatably connected to the fixed part 42a and connected to the water stop part 43. In this way, the swivel mechanism 42 is provided between the on-off valve 40 and the water stop part 43, and allows the water stop part 43 to rotate relative to the on-off valve 40.

The water stop part 43 has a housing 43a connected to the rotating part 42b of the swivel mechanism 42, an annular water stop rubber 43b housed in the housing 43a and surrounding the outer circumferential surface of the sampling pipe 35, a pair of annular collars 43c that sandwich the water stop rubber 43b from the axial direction of the sampling pipe 35, and a tightening nut 43d that is screwed to the inner circumferential surface of the housing 43a and can compress the water stop rubber 43b via the collar 43c by tightening force.

By tightening the fastening nut 43d to the housing 43a, the water stop rubber 43b is compressed between the pair of collars 43c and expands in the radial direction, so that its inner circumferential surface comes into close contact with the outer circumferential surface of the sampling pipe 35, and its outer circumferential surface comes into close contact with the inner circumferential surface of the housing 43a. This prevents water from entering the upper sampling work space 31a through the outside of the sampling pipe 35. Note that FIG. 4 shows the state before the fastening nut 43d is tightened to the housing 43a.

When the sampling pipe 35 is rotated by the electric motor 50, the water stop rubber 43b is in close contact with the outer peripheral surface of the sampling pipe 35, so the water stop part 43 including the water stop rubber 43b also rotates together with the sampling pipe 35. In addition, when the sampling pipe 35 is moved in the longitudinal direction by the moving mechanism 51, the outer peripheral surface of the sampling pipe 35 comes into sliding contact with the inner peripheral surface of the water stop rubber 43b. In this way, the sampling pipe 35 moves along the inner peripheral surface of the water stop rubber 43b, which rotates together with it.

As shown in FIG. 3, the sampling device 30 further includes a pump 60 that delivers water to the vicinity of the tip of the sampling pipe 35 to cool and protect the bit at the tip of the sampling pipe 35, and a tank 61 that stores the water delivered by the pump 60. The pump 60 and the tank 61 are disposed on the outer peripheral wall 26.

Next, the procedure for sampling soil and sand using the sampling device 30 will be described with reference to Figure 5. Figures 5(a) to (e) are diagrams showing the procedure for sampling soil and sand in chronological order. Figure 5 shows only one of the two sampling devices 30, and the partition wall 4 is not shown.

<Preparation process>
5( a ), a sealing mechanism 41 is attached to an on-off valve 40 in a closed state that is provided on a skin plate 2. In addition, a support 53 is disposed between the skin plate 2 and the outer peripheral wall 26, and the support 53 is fixed between the skin plate 2 and the outer peripheral wall 26 by tightening a jack of the support 53.

Next, the electric motor 50 is supported on the support 53 via the detachable spacer 55, and the sampling pipe 35 is connected to the output shaft of the electric motor 50. After that, the handle 54a of the moving mechanism 51 is operated to move the electric motor 50 forward along the support 53, and the sampling pipe 35 is inserted into the sealing mechanism 41 and advanced to just before the on-off valve 40.

Next, tighten the fastening nut 43d of the sealing mechanism 41 to bring the inner surface of the water-stop rubber 43b into close contact with the outer surface of the sampling pipe 35.

<Drilling process>
As shown in Fig. 5(b), the on-off valve 40 is opened to open the through hole 34 of the skin plate 2. Next, the electric motor 50 is rotated to rotate the sampling pipe 35. After that, the handle 54a of the moving mechanism 51 is operated to move the electric motor 50 forward along the support 53, and the sampling pipe 35 is advanced through the through hole 34 to the outside of the upper sampling work space 31a. As a result, the sampling pipe 35 excavates the soil around the shield machine 1, and the soil is collected inside. The sampling pipe 35 is advanced until the electric motor 50 is positioned in front of the sealing mechanism 41, and the soil is excavated and collected (the state shown in Fig. 5(b)).

Next, as shown in FIG. 5(c), the output shaft of the electric motor 50 is disconnected from the sampling pipe 35, and the detachable spacer 55 is loosened to remove the electric motor 50 from the support 53. An extension rod 37 is then connected to the lower end of the sampling pipe 35. At this time, a holder (not shown) for supporting the sampling pipe 35 on the skin plate 2 is tightened to prevent the sampling pipe 35 from falling off. A water stop ball 36 is provided inside the lower end of the sampling pipe 35 to prevent the soil collected in the sampling pipe 35 from flowing out from the lower end of the sampling pipe 35.

Next, as shown in FIG. 5(d), the electric motor 50 is supported on the support 53 via the detachable spacer 55, and the extension rod 37 is connected to the output shaft of the electric motor 50.

Then, as shown in FIG. 5(e), the handle 54a of the moving mechanism 51 is operated again to move the electric motor 50 forward along the support 53, digging is performed using the sampling pipe 35, and soil is collected. The sampling pipe 35 is advanced until the electric motor 50 is positioned in front of the sealing mechanism 41 (the state shown in FIG. 5(e)). In this way, by using the extension rod 37, soil can be collected from a desired position farther away from the shield tunneling machine 1. In other words, soil can be collected from a position closer to the ground.

In this manner, soil and sand are collected. When collecting the soil and sand, the soil pressure measured by the soil pressure gauge 39 is also obtained. In other words, the soil and sand collected by the sampling pipe 35 and the soil pressure corresponding to that soil are also obtained. This makes it possible to grasp the soil and sand conditions around the shield tunneling machine 1 more accurately.

<Recovery process>
The output shaft of the electric motor 50 is disconnected from the extension rod 37, and the detachable spacer 55 is loosened to remove the electric motor 50 from the support 53. Next, the extension rod 37 and the sampling pipe 35 are pulled out from the soil and sand and collected.

The soil sampling described above cannot be performed while the shield tunneling machine 1 is excavating, so it is performed in parallel with the assembly of the segment ring 9, which is performed while the shield tunneling machine 1 is stopped. Therefore, the construction period is not extended due to the sampling work.

The soil sampling described above may be performed only when a change in the strata is detected based on the soil pressure measured by the soil pressure gauge 39.

Sampling operations using the two sampling devices 30 may be performed simultaneously or one at a time.

The above embodiment provides the following effects:

The sampling device 30 can sample the soil around the shield tunneling machine 1, so that the properties of the soil around the shield tunneling machine 1 can be accurately understood. This prevents misjudgment of the soil properties of the excavated ground, and excavation by the shield tunneling machine 1 can be carried out based on more accurate soil properties. This allows the face to be stabilized. In particular, in low-cover tunnels and large-section shield tunnels, ground deformation around the shield tunneling machine 1 may lead to ground subsidence. However, the sampling device 30 of this embodiment is arranged on the top of the shield tunneling machine 1 and samples the soil above the skin plate 2, so that the soil properties and soil layer structure at a position closer to the ground can be confirmed to confirm the presence or absence of intervening layers. Therefore, in low-cover tunnels and large-section shield tunnels, the face can be stabilized to prevent ground deformation. Sampling by the sampling device 30 of this embodiment is particularly effective when ground boring is not possible.

The presence or absence of cavities in the ground surrounding the shield tunneling machine 1 can be determined based on the load (penetration resistance) applied by the sampling pipe 35 of the sampling device 30 during excavation. The load applied by the sampling pipe 35 during excavation can be determined by measuring the current value of the electric motor 50 that rotates the sampling pipe 35 and the current value of the electric motor that is the drive source of the moving mechanism 51 that moves the sampling pipe 35 in the longitudinal direction. The presence or absence of cavities in the ground surrounding the shield tunneling machine 1 can also be determined based on the amount of soil sampled by the sampling device 30.

A variation of the above embodiment will be described.

(1) In the above embodiment, a configuration in which two sampling devices 30 are provided has been described. However, only one sampling device 30 may be provided, or three or more sampling devices 30 may be provided.

(2) In the above embodiment, the sampling device 30 is described as being placed in the upper sampling work space 31a located above the shield tunneling machine 1 within the annular sampling work space 31. However, the sampling device 30 may be placed anywhere in the annular sampling work space 31 as long as it is capable of sampling the soil and sand around the shield tunneling machine 1.

(3) The extension rod 37 connected to the sampling pipe 35 is not a required component, and soil and sand may be collected without using the extension rod 37.

Although the embodiments of the present invention have been described above, the above embodiments merely show some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

1. Shield tunneling machine (tunnel boring machine)
2... Skin plate (torso)
3... Cutter head (digging part)
4: Partition wall 5: Cutter chamber 9: Segment ring 11: Opposing wall 26: Outer peripheral wall 30: Sampling device 31: Sampling work space 31a: Upper sampling work space 34: Through hole 35: Sampling pipe 37: Extension rod 39: Earth pressure gauge (earth pressure measuring device)
40: Opening/closing valve 41: Sealing mechanism 50: Electric motor (drive device)
51...Movement mechanism 53...Strut

Claims (6)

A tunnel boring machine for boring a tunnel into the ground,
A cylindrical body extending along the axial direction of the tunnel;
An excavation unit that is rotationally driven at the front of the body;
A bulkhead provided within the body and arranged opposite the excavated portion in the axial direction of the tunnel;
a cutter chamber partitioned by the body, the excavation section, and the partition, into which soil excavated by the excavation section flows;
A sampling device for sampling sediment;
a sampling workspace provided along the fuselage rearward of the cutter chamber, in which the sampling device is disposed;
The sampling working space has a through hole penetrating the body and capable of being opened and closed;
The sampling device comprises:
a sampling pipe capable of moving forward outside the sampling work space and backward into the sampling work space through the through hole of the body, for sampling soil and sand;
A driving device that rotates the sampling pipe.
Tunnel boring machine. 2. The tunnel boring machine according to claim 1, wherein the sampling device samples soil above the body. an opposing wall provided in the fuselage and arranged opposite the partition wall in the axial direction of the tunnel;
A peripheral wall is arranged along an inner peripheral surface of the body and at a predetermined interval from the inner peripheral surface,
The sampling work space is defined by the body, the partition wall, the opposing wall, and the peripheral wall.
A tunnel boring machine according to claim 1 or 2. The sampling device comprises:
an on-off valve that opens and closes the through hole;
4. A tunnel boring machine according to claim 1, further comprising a sealing mechanism connected to the on-off valve for preventing water from entering the sampling work space through the outside of the sampling pipe. The sampling of soil and sand by the sampling device is performed in parallel with the assembly of the segment rings in the fuselage.
A tunnel boring machine according to any one of claims 1 to 4. Further comprising an earth pressure measuring device provided on the body and measuring earth pressure acting on the body.
A tunnel boring machine according to any one of claims 1 to 5.