Measuring device for characteristics near the face

Abstract

A device for measuring properties near a tunnel face in a shield machine or tunnel boring machine that can be used without boring from above ground, etc. is provided. [Solution] The face vicinity property measuring device 6 is a face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) used in an earth pressure type shield 1 as a shield machine, and includes an exploration tool 61 stored in the shield machine or tunnel boring machine and reaching the face vicinity FA, ​​a jack 62 as an advancing / retracting means for moving the exploration tool 61 back and forth between the shield machine or tunnel boring machine and the face vicinity FA, ​​and a displacement sensor 66 for detecting the amount of displacement of the exploration tool 61. Of these, the exploration tool 61 is stored in a fixed mixing blade 55 protruding from a partition 3 of the shield machine into a chamber 16.

Description

[Technical field]

[0001] The present invention relates to a device for measuring properties near a tunnel face, including displacement near the face, earth pressure near the face, pore water pressure near the face, pressure in a chamber, and / or pore water pressure in a chamber, from inside a tunnel boring machine, including a shield machine or a tunnel boring machine. [Background technology]

[0002] Conventionally, in shield construction, ground deformation in front of and around the shield machine has been measured using inclinometers and the like that utilize boreholes from the ground. In such cases, there are many cases where road restrictions are imposed due to environmental conditions on the ground, or measurements cannot be taken at any desired location due to soil covering problems. The present invention relates to a device that directly measures properties near the face, including displacement, earth pressure, and / or pore water pressure near the face (e.g., forward) at any desired location.

[0003] In this regard, "near the face" in the present invention means the face surface in contact with the shield machine cutter head, in front of the face (about 1D), and the area outside the outer periphery of the shield (about 1D) (D: outer diameter of excavation), but it is particularly preferable to be able to measure the characteristics of the face and in front of the face (about 1D).

[0004] For example, in the case of an earth pressure shield, which is a type of tunnel boring machine, if the pressure inside the chamber is properly managed, the face will not displace significantly, and as a result, the displacement of the surrounding ground can be suppressed. Conventional methods for managing the mud pressure inside the chamber of an earth pressure shield include method 1) and method 2) shown below.

[0005] 1) A method of calculating active earth pressure, passive earth pressure, static earth pressure, etc. using a formula for calculating earth pressure from the soil constants (φ, C, γ, etc.) of the target ground estimated by a prior soil survey, the groundwater level, and the overburden load, and then setting and managing upper and lower limits of the mud soil pressure in the chamber based on these values ​​(see, for example, Patent Document 1).

[0006] 2) A method of setting the controlled earth pressure based on the muddy earth pressure in the chamber measured when the shield is stopped (see, for example, non-patent document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2012-233372 A [Non-Patent Document 1] "Guidelines for safe and secure construction of shield tunnels," Shield Tunnel Construction Technology Review Committee, December 2021, p. 19 Summary of the Invention [Problem to be solved by the invention]

[0008] Issues with method 1): A preliminary soil survey is usually carried out by boring, and is usually carried out at intervals of about 200m along the length of the line. Therefore, if the soil conditions change during that time, it may not be possible to calculate the appropriate control pressure. In addition, since the calculation formula for earth pressure is theoretical, it is not always possible to accurately calculate the earth pressure of the actual ground.

[0009] In addition, shield tunneling routes are almost always planned with road facilities above ground, and since boring and measuring work from above ground would require road restrictions, it is not possible to frequently measure deformation of the ground near the tunnel face. In addition, the planned depth in urban areas is very deep, and there are often tunnel structures and lifelines in use between the tunnel and the ground, making it physically impossible to carry out the work.

[0010] Furthermore, when measuring the displacement in front of the shield machine using a boring tool, it is necessary to temporarily halt excavation because the measuring device must be retrieved before the shield machine reaches the measurement position. Also, there is a risk that the borehole will become a waterway, causing problems such as the sudden outflow of muddy water.

[0011] Issues with method 2): The muddy earth pressure measured when the shield is stopped is thought to reflect the earth pressure acting on the face relatively accurately if the shield itself is not moving and the cutter has no face plate. However, if these conditions are not maintained, the earth pressure measured when the shield is stopped does not necessarily represent the static earth pressure or active earth pressure of the ground.

[0012] With the above-described pressure control method within the chamber, there is a possibility that an appropriate controlled pressure cannot be set if ground conditions, etc. change.

[0013] Therefore, the present invention aims to provide a device for measuring properties near the face that can measure the ground properties around the tunnel face (especially the front) at any position regardless of the conditions on the ground or in the intermediate areas, and without interrupting or causing problems to work, by directly measuring the properties near the face from inside a shield machine or a tunnel boring machine, including a tunnel boring machine, rather than using a means for measuring displacement near the face from the ground. [Means for solving the problem]

[0014] In order to solve the above problems, the present invention provides a measuring device for measuring properties near the face, which is used in a tunnel excavator and includes an exploration tool stored in the tunnel excavator and reaching the vicinity of the face, an advance / retract means for moving the exploration tool back and forth between the tunnel excavator and the vicinity of the face, a displacement sensor for detecting the amount of displacement of the exploration tool, a pressure gauge for measuring the earth pressure near the face, and / or a water pressure gauge for measuring the pore water pressure near the face. Here, "inside the tunnel excavator" refers not only to the area including the rear side (the tunnel mouth side) of the partition wall, but also to the area including the cutter spokes, the storage box installed behind the cutter and in front of the partition wall, the cutter face plate, and the inside of the mixing blade.

[0015] In addition, the controlled earth pressure setting system of the present invention is a controlled earth pressure setting system for a tunnel boring machine, and comprises a pressure gauge that measures the mud pressure in a chamber, a mud pressure changing means that changes the mud pressure in the chamber, the above-mentioned near-face property measuring device, an analysis unit that analyzes the deformation characteristics of the ground based on the measured mud pressure and the measured face displacement, and a setting unit that sets the controlled earth pressure based on the analyzed deformation characteristics. Effect of the Invention

[0016] In this way, the near-face property measuring device of the present invention comprises an exploration tool that is stored in the tunnel boring machine and reaches the vicinity of the face, an advancing / retreating means for moving the exploration tool back and forth between the tunnel boring machine and the vicinity of the face, a displacement sensor that detects the amount of displacement of the exploration tool, an earth pressure gauge that measures earth pressure near the face, and / or a water pressure gauge that measures pore water pressure near the face. Therefore, the properties near the face can be accurately detected based on actual measurements at any measurement position.

[0017] The system for setting the controlled earth pressure in a tunnel boring machine of the present invention comprises a pressure gauge which measures the mud pressure in the chamber, a mud pressure changing means which changes the mud pressure in the chamber, the above-mentioned near-face property measuring device, an analysis section which analyzes the deformation characteristics of the ground based on the measured mud pressure and the measured displacement near the face, and a setting section which sets the controlled earth pressure based on the analyzed deformation characteristics. Therefore, the system for setting the controlled earth pressure in a tunnel boring machine is one which does not set the controlled pressure based on assumptions or estimates, but can confirm the validity of the controlled pressure by directly measuring the displacement near the face. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a cross-sectional view illustrating the internal structure of a shield tunneling machine. [Diagram 2] FIG. 2 is a cross-sectional view illustrating the configuration of the face vicinity property measuring device of the first embodiment when stored. [Diagram 3] FIG. 2 is a cross-sectional view for explaining the configuration of the face vicinity property measuring device of the first embodiment when it reaches the face. [Figure 4] FIG. 11 is an explanatory diagram illustrating variations in the tip shape of the exploration jig. [Diagram 5] FIG. 2 is a cross-sectional view for explaining the configuration of the face vicinity property measuring device of the first and second modified examples. [Figure 6] FIG. 11 is a cross-sectional view illustrating the configuration of the face vicinity property measuring device of the third modified example when it is stored. [Figure 7] 13 is an explanatory diagram of the configuration of a third modified example of a measuring device for properties in the vicinity of the face, in which (a) shows the configuration in the middle and (b) shows the configuration upon reaching the face. [Figure 8] FIG. 13 is an explanatory diagram of the configuration of a face vicinity property measuring device of a fourth modified example. [Figure 9] FIG. 13 is an explanatory diagram of the configuration of a face vicinity property measuring device of a fifth modified example. [Figure 10] 10 is a flowchart illustrating the procedure of a system for setting controlled earth pressure. [Figure 11] 1 is a graph showing the relationship between mud pressure and horizontal displacement in a depressurization test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the components described in the following embodiments are merely examples, and are not intended to limit the technical scope of the present invention to these alone. In the following, an earth pressure shield 1 will be described as an example of a tunnel boring machine, but the present invention can also be applied to other types of tunnel boring machines, such as a muddy water shield, a muddy earth pressure shield, an air bubble shield, a muddy slurry shield, a thick muddy slurry shield, and a tunnel boring machine. EXAMPLES

[0020] (Shield tunneling machine configuration) Fig. 1 is a vertical cross-sectional side view showing an embodiment of the present invention. As shown in Fig. 1, an earth pressure shield 1 as a tunnel boring machine of this embodiment includes a skin plate (shield body cylinder) 2, a bulkhead 3, a cutter head 5, a cutter rotating shaft 10, a cutter driving unit 12, a chamber 16, an earth removal device 17, a shield propulsion jack 18, a mud material supply pipe 21, a pressure gauge 22, a water pressure gauge 23, and a control unit 40 including an analysis unit 41 and a setting unit 42 arranged inside an operation room or the like.

[0021] The cutter head 5 has cutter spokes 51, a plurality of cutter bits 52, ... provided on the front surface of the cutter spokes 51, a fishtail bit 53 provided in the center of the front surface of the cutter spokes 51, and a plurality of stirring blades 54, ... provided on the back surface of the cutter spokes 51. The cutter head 5 is attached integrally to the cutter rotation shaft 10.

[0022] The cutter rotating shaft 10 is rotatably supported by a bearing 11 provided in the partition 3 and a bearing provided at the rear of a gear box 13 described below. The cutter rotating shaft 10 is connected to a cutter driving unit 12. The cutter driving unit 12 has a gear box 13 installed on the rear side of the partition 3, a rotational drive source 14 connected to the gear box 13, and a reduction gear (arranged in the gear box 13; not shown) interposed between the output shaft of the rotational drive source 14 and the cutter rotating shaft 10.

[0023] The chamber 16 is formed in a space surrounded by the hood portion 2a of the skin plate 2, the partition wall 3, and the face F. A screw conveyor, for example, is used as the soil discharge device 17. The mud intake port of the soil discharge device 17 is opened and installed so as to face the chamber 16. In this embodiment, the soil discharge device 17 also functions as a mud pressure changing means.

[0024] Furthermore, an erector 15 for assembling the segments 90 is installed in the tail portion 2b of the skin plate 2. Furthermore, a plurality of shield propulsion jacks 18 are installed at required intervals in the circumferential direction inside the skin plate 2. In addition, a tail seal 19 is provided at the rear end portion of the skin plate 2.

[0025] (Configuration of the face vicinity property measuring device 6) The earth pressure type shield 1 as the shield tunneling machine of this embodiment further includes a near-face property measuring device 6 that measures the displacement of the tunnel face and / or the vicinity of the tunnel face. Here, the on-board measurement type near-face property measuring device 6 that measures the properties near the tunnel face from inside the machine will be described with reference to Figs. 2 and 3. Here, the properties near the tunnel face refer to at least one of the three properties: displacement near the tunnel face, earth pressure near the tunnel face, or pore water pressure near the tunnel face, and two or more properties may be measured.

[0026] As shown in Fig. 2, the face vicinity property measuring device 6 of this embodiment is a rod-shaped probe 61 having a sufficient length to penetrate the partition 3 and the fixed mixing blade 55 and reach, abut or penetrate the face vicinity FA with the tip 610, a hydraulic chuck 63 that moves / opens the probe 61 by gripping / releasing the probe 61 with the extension / retraction of the jacks 62, 62 as advancing / retracting means, a detection unit 64 attached integrally to the end of the probe 61, a guide 65 that supports the sliding movement of the detection unit 64, a displacement sensor 66 that measures the displacement amount of the probe 61 by measuring the distance to the detection unit 64, a water stop device 67 for the probe 61, and water stop valves 68, 68A. Here, the face vicinity property measuring device 6 of this embodiment will be described in the case where the "displacement" near the face is measured as a property near the face.

[0027] That is, in this embodiment, the exploration jig 61 is stored in the fixed stirring blade 55 protruding from the partition 3 into the chamber 16 so as to be able to freely appear and disappear (move forward and backward; move in and out). That is, the fixed stirring blade 55 has a hole (in which the rod-shaped main body 613 of the exploration jig 61 is inserted) formed through the center of the cross section along the axial direction. In this way, the exploration jig 61 (the tip 610) moves and reaches from the tip of the fixed stirring blade 55 to the vicinity of the face FA and abuts or penetrates. Note that in this embodiment, the exploration jig is expressed as moving and reaching the vicinity of the face using the fixed stirring blade and abutting or penetrating it, but if it has a similar shape (for example, a dedicated storage box 55A is separately prepared), it does not have to fulfill the purpose of the fixed stirring blade.

[0028] The detection jig 61 is composed of a rod-shaped main body 613 and a tip 610 formed at the tip of the main body. The end of the main body is gripped by a hydraulic chuck 63. As will be described later with reference to Figures 4(a) to (f), the shape of the tip 610 may be a protruding cone portion 611a, or a shape combining an expanded flange portion 612 and a cone portion 611a in the center of the flange portion 612.

[0029] Therefore, when the hydraulic chuck 63 grips the exploration jig 61, the exploration jig 61 retreats when the jacks 62, 62 extend, and the exploration jig 61 advances when the jacks 62 retract. When the hydraulic chuck 63 is released, the exploration jig 61 is free. Therefore, in the open state (the exploration jig 61 can move freely), if the tip 610 of the exploration jig 61 abuts or penetrates the FA near the face, the exploration jig 61 moves (in the tunnel longitudinal direction) in accordance with the displacement of the FA near the face. As described later, in the present invention, the mud pressure in the chamber 16 is reduced, causing the FA near the face to protrude slightly, so that the exploration jig 61 moves in the tunnel longitudinal direction toward the tunnel mouth.

[0030] (Operation Procedure) Next, with reference to Figs. 2 and 3, the operating procedure of the face vicinity property measuring device 6 equipped with the exploration jig 61, the jack 62 as the advancing and retreating means, and the displacement sensor 66 in the depressurization test of this embodiment will be described. 1. During shield tunneling, the exploration tool 61 is retracted to the position of the fixed mixing blade 55 (FIG. 2). In other words, the exploration tool 61 is housed at the tip of the fixed mixing blade 55 by extending the jack 62. 2. After the shield stops, the hydraulic chuck 63 grips the detection jig 61 and slides it to a position where the tip 610 abuts on or penetrates the face F or the vicinity of the face FA (see FIG. 3). At this time, the jack 62 is retracted. 3. After the tip 610 of the detection tool 61 is brought into contact with or penetrates the tunnel face F or the area near the tunnel face FA, the hydraulic chuck 63 is released. This allows the detection tool 61 to move freely in the tunnel longitudinal direction (front-rear direction) without being restricted. 4. Operate the soil discharge means (soil discharge device 17) at a slow speed to gradually reduce the soil pressure in the chamber 16. 5. When the face F or the area near the face FA is displaced due to the reduction in pressure, the displacement pushes the detection jig 61 toward the inside of the shield. 6. A measuring device (a detection unit 64, a displacement sensor 66) is attached inside the shield of the detection jig 61. The amount of displacement is measured by the displacement sensor 66 through the detection unit 64. 7. The measurement value is sent from the displacement sensor 66 to the PC. At the same time, the mud pressure in the chamber 16 is measured by the pressure gauge 22 installed in the bulkhead 3. 8. Using the above procedure, the relationship between the mud pressure in the chamber 16 and the displacement of the face F or FA near the face is determined. 9. The depressurization test is stopped when all or part of the transition region (including the yield point) in the displacement near the face becomes clear. 10. Then, for example, the soil discharge means (soil discharge device 17) is reversed to return the mud and increase the mud pressure in the chamber 16 to the initial state. 11. The detecting jig 61 is gripped again by the hydraulic chuck 63 and pulled back by operating the jack 62, and the detecting jig 61 is retracted to the position of the fixed mixing blade 55 (see FIG. 2). At this time, the jack 62 is extended.

[0031] (Variations of the tip of the inspection tool) 4(a) to 4(f) will be used to explain various aspects of the tip 610 of the detection jig 61. Note that the tip 610 of the detection jig 61 is not limited to the examples and modified examples described below.

[0032] First, as shown in FIG. 4(a), a tip 610 of a detection jig 61 of the embodiment is composed of a cone portion 611a protruding from the tip.

[0033] Next, as shown in Fig. 4(b), the tip 610 of the exploration jig 61 of the embodiment is composed of a flange portion 612 and a cone portion 611a protruding from the tip. The presence of the flange portion 612 in this way makes it easier for the tip 610 to move together with the natural ground (towards the near side; towards the pit mouth).

[0034] Next, as shown in Fig. 4(c), tip 610 of the modified example is composed of flange portion 612 and one (thin) arrow portion 611b having a cone-shaped "barb" at the tip. By having such a barb, tip 610 that is stuck into the natural ground becomes one with the natural ground and is difficult to come out.

[0035] Next, as shown in Fig. 4(d), tip 610 of another modified example is composed of flange portion 612 and multiple (here, two; thin-diameter) arrow portions 611b, 611b having cone-shaped barbs at the tip. By having multiple arrow portions 611b, ... in this way, tip 610 stuck in the natural ground becomes even more difficult to come out.

[0036] Next, as shown in Fig. 4(e), tip 610 of another modified example is composed of flange portion 612 and drill portion 611c having a drill shape at the tip. By providing drill portion 611c, tip 610 stuck in the natural ground becomes one with the natural ground and is difficult to come out. It is preferable that drill portion 611c is freely rotatable around its axis.

[0037] 4(f), tip 610 of another modified example does not have a flange (612) and is composed of only one (thin) arrow portion 611b having a cone-shaped barb at the tip. In this way, the absence of a flange makes it easier to pass through chamber 16.

[0038] (First Modification: Configuration of the Face Neighborhood Property Measuring Device 6A) Next, the configuration of the face vicinity property measuring device 6A of the first modified example will be described with reference to Fig. 5. As shown in the upper part of Fig. 5, in the face vicinity property measuring device 6A of this modified example, the cylinder part 62a and the rod part 62b of the jack 62 as an advancing and retreating means are stored in the fixed mixing blade 55. That is, in the embodiment, the jack 62 is configured to be attached to the rear (inside the machine) of the bulkhead 3, but in this modified example, the jack 62 penetrates the bulkhead 3 and is stored in the fixed mixing blade 55 or the storage box 55A. The face vicinity property measuring device 6A of this modified example will be described for the case where it measures "displacement" near the face as a property near the face.

[0039] The rod portion 62b of the jack 62 serves as the detection jig 61, which protrudes from the tip of the fixed mixing blade 55 or the storage box 55A and reaches, abuts, or penetrates the vicinity of the face FA. Specifically, the displacement measurement method is such that a through hole is provided along the axial direction at the center of the cross section of the detection jig 61 (62b), and the rod of the displacement sensor 66 is inserted into the through hole. When the detection jig 61 slides back and forth, the relative displacement between the detection portion 64 attached to the detection jig 61 and the rod of the displacement sensor 66 can be measured.

[0040] In this case, the measurement procedure is as follows. 1) During shield tunneling, the rod portion 62b of the exploration jig 61 is stored in the fixed mixing impeller 55 or in the storage box 55A. 2) When the shield is stopped, the jack 62 is operated to extend the detection jig 61 (i.e., the rod portion 62b) forward so that the tip of the detection jig 61 abuts against or penetrates the FA near the face. 3) After the detection jig 61 is securely in contact with or penetrates the tunnel face FA, the hydraulic pressure of the jack 62 is released so that the detection jig 61 can move freely. 4) In this state, when the FA near the face is displaced, the detection jig 61 is pushed back and the amount of displacement can be measured by the detection unit 64 and the displacement sensor 66. In this modified example, the cylinder portion 62a of the jack 62 that slides the inspection jig 61 penetrates the partition and is positioned inside the fixed mixing blade 55 or inside the storage box 55A, so that the amount of protrusion rearward of the partition 3 can be made even shorter than in the embodiment.

[0041] (Second modified example: configuration of face vicinity property measuring device 6B) Next, the configuration of the face vicinity property measuring device 6B of the second modified example will be described with reference to Fig. 5. As shown in the center of Fig. 5, in the face vicinity property measuring device 6B of this modified example, the cylinder part 62a and the rod part 62b of the jack 62 serving as an advancing and retreating means are stored in the cutter spokes 51. That is, while in the embodiment, the jack 62 is configured to be attached to the rear (machine inside) of the bulkhead 3, in this modified example, the jack 62 is accommodated in the cutter spokes 51. The face vicinity property measuring device 6B of this modified example will be described for the case where it measures the "displacement" of the face as a property of the face.

[0042] Furthermore, in this modified example, if the length of the near-face property measuring device 6B is longer than the depth of the cutter spokes 51, the rear part of the near-face property measuring device 6B may be placed inside the (movable) mixing blade 54. In this case, as long as the device is large enough to be placed (for example, using a storage box 54A), it does not have to fulfill the purpose of the (movable) mixing blade. The rod portion 62b of the jack 62 serves as the detection jig 61, and protrudes from the surface on the face side of the cutter spokes 51 and reaches, abuts, or penetrates the near-face FA.

[0043] As in the first modification, the displacement measurement method is the same as the first modification, in which a through hole is provided in the center of the cross section of the probe 61 (62b) along the axial direction, and the rod of the displacement sensor 66 is inserted. When the cutter bit 52 is the tip 610, a through hole is provided on the face side of the cutter spoke 51. When the probe 61 slides back and forth, the relative displacement between the detection unit 64 attached to the probe 61 and the rod of the displacement sensor 66 can be measured. At this time, the hydraulic oil line for driving the jack 62 and the signal line from the displacement sensor 66 are led through the cutter rotation shaft 10 to the inside of the shield machine behind the bulkhead 3. The measurement procedure is the same as that of the face vicinity property measuring device 6A of the first modification, so a description thereof will be omitted.

[0044] (Third Modification: Configuration of the Face Neighborhood Property Measuring Device 6C) Next, the configuration of the face vicinity property measuring device 6C of the third modified example will be described with reference to Fig. 6. As shown in Fig. 6, the face vicinity property measuring device 6C of this modified example is configured such that a jack 62 (cylinder part 62a and rod part 62b) as an advancing and retreating means and an exploration jig is advanced and retreated into the chamber 16 from the machine inside through the bulkhead 3. That is, in the embodiment, the jack 62 is configured to be attached to the rear (machine inside) of the bulkhead 3, but in this modified example, the jack 62 (combined exploration jig 61) itself is advanced and retreated by the second jacks 69, 69 as an in-machine advancing and retreating means. The face vicinity property measuring device 6C of this modified example will be described in the case where the "displacement" of the face is measured as the face property.

[0045] That is, in this modification, the jack 62 in the fixed mixing blade 55 or the storage box 55A described in the first modification has a sliding structure. Specifically, the jack 62 is held by the second jacks 69, 69 as the inboard advancing and retreating means via the bracket 70, and the second jacks 69, 69 are attached to the back side of the bulkhead 3 so as to receive a reaction force. Therefore, the jack 62 moves to the inboard side by extending the second jack 69, and moves to the face F side by contracting the second jack 69. Then, when the second jack 69 is contracted and the jack 62 is on the face F side, the jack 62 is extended so that the rod portion 62b abuts or penetrates the face vicinity FA.

[0046] As in the first and second modified examples, the displacement measurement method is such that a through hole is provided along the axial direction at the center of the cross section of the detecting jig 61 (62b), and the rod of the displacement sensor 66 is inserted into the through hole. When the detecting jig 61 slides back and forth, the relative displacement between the detection unit 64 attached to the detecting jig 61 and the rod of the displacement sensor 66 can be measured.

[0047] The measurement procedure in this case is as follows. 1) During shield tunneling, the rod portion 62b of the exploration tool 61 is stored inside the bulkhead 3 (see FIG. 6). 2) When the shield is stopped, the second jack 69 is retracted to move the jack 62 forward (see FIG. 7(a)). 3) After that, the jack 62 is extended so that the rod portion 62b, that is, the detection jig 61 reaches and abuts against or penetrates the vicinity of the tunnel face (see FIG. 7(b)). 4) After the detection jig 61 is securely in contact with or penetrates the tunnel face F, the hydraulic pressure of the jack 62 is released so that the detection jig 61 can move freely. 5) In this state, when the FA near the face is displaced, the detection jig 61 is pushed back and the amount of displacement can be measured by the detection unit 64 and the displacement sensor 66.

[0048] In this way, by dividing the required stroke into two stages, the amount of protrusion of the face vicinity property measuring device 6C into the machine is reduced. During excavation, the state is as shown in FIG. 6, so the fixed mixing blades (55) do not protrude into the chamber 16. With this structure, deformation and damage to the face vicinity property measuring device 6C caused by getting stuck in large gravel in the excavated ground can be prevented.

[0049] (Fourth Modification: Configuration of Face Neighborhood Property Measuring Device 6D) Next, the configuration of the face vicinity property measuring device 6D of the fourth modified example will be described with reference to FIG. 8. As shown in FIG. 8, in the face vicinity property measuring device 6D of this modified example, the cylinder part 62a and the rod part 62b of the jack 62 as a moving means are stored in the cutter spoke 51 and the mixing blade 54. If the size of the cutter spoke 51 is sufficiently large, the face vicinity property measuring device 6D can be stored in the cutter spoke 51 without using the mixing blade (54). Even if it is protruded backward, it is not necessarily required to have the function of the mixing blade (54). For example, a storage box 54A large enough to store the device may be newly provided. That is, in the embodiment, the jack 62 is configured to be attached to the rear (machine inner side) of the bulkhead 3, but in this modified example, the jack 62 is stored in the cutter spoke 51 and the mixing blade 54, or in the storage box 54A, as in the second modified example. The case where the vicinity of the tunnel face property measuring device 6D of this modified example measures "earth pressure" in the vicinity of the tunnel face as the property in the vicinity of the tunnel face will be described.

[0050] More specifically, in this modification, the length of the near-face property measuring device 6D is longer than the depth of the cutter spokes 51, so the rear part of the near-face property measuring device 6D is arranged inside the (moving) mixing blade 54. The rod part 62b of the jack 62 is integrated with the detecting jig 61, so that the cutter bit 52 installed on the face side of the detecting jig 61 reaches, abuts or penetrates the near-face FA.

[0051] In this modified example, the tip 610 of the rod portion 62b is integrated with the cutter bit 52. In this case, when not performing measurement, for example during excavation work, the tip 610 can be retracted rearward from the other cutter bits 52 to prevent wear on the cutter bit 52 and damage to the measuring device. Furthermore, since the cutter spokes 51 rotate, measurement can be performed at any position on the circumference, and the range of measurement positions can be expanded.

[0052] Furthermore, in the face vicinity property measuring device 6D of this embodiment, the tip 610 of the rod portion 62b is the cutter bit 52. Therefore, if the exploration jig 61 is configured to be extended to the position of the face vicinity FA before stopping excavation, it is possible to reliably abut the exploration jig 61 against the face even in hard ground that is difficult to penetrate.

[0053] Additionally, the face vicinity property measuring device 6D has an earth pressure gauge 22A for measuring earth pressure in the face vicinity FA, ​​in addition to the displacement sensor 66 similar to the embodiment. In this modification, the earth pressure gauge 22A is embedded in a recess provided in the approximate center of the cutter bit 52. As described above, the cutter bit 52 is attached to the face side (tip side) of the exploration jig 61 integrated with the jack 62, and therefore can be moved forward and backward by the operation of the jack 62.

[0054] In this modified example, the case where the earth pressure gauge 22A is installed in the cutter bit 52 has been described, but the present invention is not limited to this, and the water pressure gauge 23A may be installed instead of the earth pressure gauge 22A to measure the pore water pressure. These measuring instruments do not have to be arranged in the center of the cutter bit 52 as described in the embodiment, and may be arranged on the side of the cutter bit 52 or on the cutter spokes 51. In this case, it is more preferable to install them at the same depth position.

[0055] (Fifth Modification: Configuration of Face Vicinity Property Measuring Device 6E) Next, the configuration of the face vicinity property measuring device 6E of the fifth modified example will be described with reference to FIG. 9. As shown in FIG. 9, in the face vicinity property measuring device 6E of this modified example, the cylinder part 62a and the rod part 62b of the jack 62 as the advancing and retreating means are stored in the cutter spoke 51 and the (movable) stirring blade 54, or in the storage box 54A, as in the fourth modified example. If the size of the cutter spoke 51 is large enough, it is possible to store it in the cutter spoke 51 without using the stirring blade or the like. Even if storage is required, it is not necessarily required to have the function of the stirring blade, and it is sufficient if the device is large enough to store it. That is, in the embodiment, the jack 62 is configured to be attached to the rear (machine inside) of the bulkhead 3, but in this modified example, the jack 62 is configured to be stored in the cutter spoke 51 and the (movable) stirring blade 54, or in the storage box 54A, as in the second and fourth modified examples. The case where the vicinity-of-face property measuring device 6E of this modified example measures the "earth pressure" near the face and the "pressure in the chamber" as the properties near the face will be described.

[0056] More specifically, in this modification, the length of the face vicinity property measuring device 6E is longer than the depth of the cutter spokes 51, so the rear part of the face vicinity property measuring device 6E is disposed inside the (moving) mixing blade 54 or the storage box 54A. The rod part 62b of the jack 62 is integrated with the exploration jig 61, and the cutter bit 52 installed on the face side of the exploration jig 61 reaches the face vicinity FA and abuts or penetrates it.

[0057] In this modification, the tip and the trailing part of the bit 52 have the same cross-sectional shape. This makes it easier to penetrate into the vicinity of the face, and also prevents the erroneous ingestion of soil into the machine (cutter spokes) when the face vicinity property device 6E is retrieved and stored (see FIG. 9). Also, as in the fourth modification, if the exploration tool 61 is configured to be extended to the position of the face vicinity FA before stopping excavation, it becomes possible to reliably abut the exploration tool 61 against the face even in hard ground where penetration is difficult.

[0058] In this modification, the tip 610 of the rod portion 62b is integrated with the cutter bit 52. In this case, when not measuring (for example, during excavation work), the tip 610 is retracted rearward from the other cutter bits 52, thereby making it possible to prevent wear on the cutter bits 52 and damage to the measuring device. Furthermore, because the cutter spokes 51 rotate, it is possible to measure at any position on the circumference, thereby expanding the range of measurement positions.

[0059] Additionally, the face vicinity property measuring device 6E has an earth pressure gauge 22A for measuring earth pressure in the face vicinity FA, ​​in addition to the displacement sensor 66 similar to the embodiment. In this modification, the earth pressure gauge 22A is embedded in a recess provided in the approximate center of the cutter bit 52, and one or more earth pressure gauges are provided on the bit side (rear of the tip position). As described above, the cutter bit 52 is attached to the face side (tip side) of the exploration jig 61 integrated with the jack 62, and therefore can be moved forward and backward by the operation of the jack 62.

[0060] In this modified example, by inserting the cutter bit 52 into the vicinity of the tunnel face, it becomes possible to measure the earth pressure in the vicinity of the tunnel face and the pressure (mud pressure) in the chamber.

[0061] In this modification, the case where the earth pressure gauge 22A is installed on the cutter bit 52 has been described, but this is not limiting, and the pore water pressure may be measured by installing a water pressure gauge 23A instead of the earth pressure gauge 22A, as in the fourth modification. This makes it possible to measure the pore water pressure near the face and the pore water pressure in the chamber.

[0062] (Configuration of the controlled earth pressure setting system) In addition, the earth pressure shield 1 further includes a control unit 40 (see FIG. 1). The control unit 40 is, for example, a general-purpose personal computer having a memory, a CPU, an SSD, and the like. The control unit 40 sets the managed earth pressure of the earth pressure shield 1 and controls the excavation. That is, during excavation, the earth pressure is changed by discharging the earth using the earth discharge device 17 (screw conveyor) as an earth pressure changing means while advancing the earth pressure shield 1 using the shield propulsion jack 18, and at the same time, the earth pressure is measured using the pressure gauge 22. Furthermore, the water pressure is measured using the water pressure gauge 23. It is of course possible that the functions of the analysis unit 41 and the setting unit 42 described later can be executed by a control unit (computing device; personal computer) separate from the control unit 40 that controls the excavation of the earth pressure shield 1. In this sense, the control unit can also be called a "computing unit".

[0063] The control unit 40 of this embodiment further has a function as an analysis unit 41 that analyzes the deformation characteristics of the ground based on the properties near the face, such as the measured mud pressure, the measured displacement near the face (e.g., horizontal displacement), and the measured pore water pressure, and a function as a setting unit 42 that sets the controlled earth pressure based on the analyzed deformation characteristics. The control unit 40 is connected to input means such as a keyboard and a mouse, as well as to the earth pressure value from the pressure gauge 22 (22A), the pore water pressure value from the water pressure gauge 23 (23A), and the input value (displacement) from the displacement sensor 66 via a communication cable 43. Furthermore, the control unit 40 is connected to a monitor, a separate PC for excavation management, and the like, as output means. The functions of the analysis unit 41 and the setting unit 42 will be described in the control flow described next.

[0064] The controlled earth pressure setting system S of the present invention is composed of the above-mentioned pressure gauge 22, water pressure gauge 23, earth removal device 17 as a mud pressure changing means, face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E), and control unit 40 including an analysis unit 41 and a setting unit 42.

[0065] (action) Next, the flow of the controlled earth pressure setting system S of this embodiment will be described with reference to Figures 10 and 11. As shown in Figure 10, the flow of the controlled earth pressure setting system S is realized by executing the following steps S1 to S14.

[0066] Initial value processing (step S1) First, an initial value of the controlled earth pressure is set (step S2) based on the initial calculated earth pressure set by a boring test or the like (step S1). Then, the shield is advanced according to this initial value of the controlled earth pressure (step S3). That is, in the initial stage after the shield starts advancing (before the decompression test is carried out), the controlled earth pressure is set based on the theoretical earth pressure calculated from the soil constants obtained from the preliminary soil survey. Alternatively, the mechanical constants of the ground obtained from the preliminary soil survey are given to the 3D-FEM model, and the controlled earth pressure is set from the relationship between the earth pressure and the displacement of the ground.

[0067] Decompression test (steps S4 to S8) Next, the mud pressure in the chamber is reduced while the shield machine is stopped and not retreated (step S4). That is, when the excavation is stopped, such as when assembling the segment 90, the screw conveyor is rotated at a slow speed to gradually discharge the mud in the chamber 16 and reduce the pressure. During the reduction in pressure, the mud pressure is measured by the pressure gauge 22. At the same time, the water pressure is measured by the water pressure gauge 23 (23A). Furthermore, during the reduction in pressure, the displacement of the FA near the face is directly measured by the face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) (step S5). Based on the measured mud pressure and the displacement near the face (e.g., horizontal displacement), the deformation characteristics are grasped (step S6). That is, the mud pressure-face displacement is plotted on a graph to obtain the deformation characteristics (see FIG. 10). Once the deformation characteristics are grasped, the mechanical constants of the ground are analyzed by back analysis (step S7) (step S8).

[0068] 3D-FEM model analysis (steps S9 to S12) Then, a 3D-FEM analysis is performed using the mechanical constants of the ground analyzed by the depressurization test (step S9). Then, the impact on the surrounding ground and adjacent structures is predicted by this 3D-FEM model analysis (step S10).

[0069] That is, when the deformation characteristics of the target ground are clarified by the depressurization test, the mechanical constants of the ground are calculated (step S8) by back analysis of the ground model based on the in-situ boundary conditions such as the ground structure assumed from the boring survey and the measured water pressure (step S7). Using the mechanical constants of the ground calculated in this way, a 3D-FEM analysis is performed (step S9).

[0070] As a result of the analysis, the presence or absence of harmful effects is determined by judging whether the amount of ground surface subsidence, etc. is within the allowable displacement amount (step S11). If harmful effects are found (YES in step S11), the controlled earth pressure is changed (step S12) and the analysis is redone (steps S9 to S11). On the other hand, if harmless (NO in step S11), the process returns to step S2 and the controlled earth pressure setting system S is executed at the next position and time.

[0071] Here, the mechanical constants are, for example, Young's modulus, Poisson's ratio, internal friction angle, and cohesion. A rational simulation of behavior can be performed by adopting an FEM model based on the ground characteristics obtained based on this on-site behavior. A rational simulation based on the above-mentioned on-site behavior makes it possible to predict the ground surface subsidence and the impact on adjacent structures in advance and more accurately, minimizing the impact on the surrounding area or setting the controlled earth pressure corresponding to the regulated values ​​for ground displacement, etc.

[0072] Analysis and settings (steps S13 to S14) On the other hand, if the deformation characteristics of the ground are grasped, the yield point earth pressure is obtained by analysis from the muddy earth pressure-displacement graph as shown in FIG. 11 (step S13). That is, the analysis unit 41 of the control unit 40 finds the point where the gradient suddenly increases, regards this point as the yield point, and obtains the active earth pressure. For example, an approximation line can be obtained from a plurality of plots in the elastic region by the least squares method, and an approximation line can be obtained from a plurality of plots in the plastic region, and the intersection of these can be regarded as the yield point. Alternatively, it can be estimated that the transition region has been entered by the appearance of consecutive plots that are significantly different from the moving average. Then, if a 3D-FEM model analysis is required due to the presence of buildings nearby, etc. ("required" in step S14), the impact on the surrounding ground and adjacent structures is predicted by the 3D-FEM analysis (step S10). If a 3D-FEM model analysis is not required ("not required" in step S14), the control earth pressure is reset based on the active earth pressure (step S2). Specifically, the controlled earth pressure in the chamber 16 during excavation must not fall below the active earth pressure plus water pressure, so the controlled earth pressure must be adjusted to, for example, 0 to 20 kN / m 2 ) is set as the lower limit of the controlled earth pressure. On the other hand, the upper limit of the controlled earth pressure may be theoretically calculated using C and φ calculated backward from the active earth pressure (yield point earth pressure), or may be set as a value that further takes into account the above lower limit and the construction fluctuation range. On the other hand, if a 3D-FEM model analysis is required ("Required" in step S14), the 3D-FEM model analysis is executed (step S9).

[0073] In this way, the observed digital values ​​(observed values) are compared with the digital values ​​(analytical values) obtained through analysis using a model ground, and the model is constantly corrected to create a model ground that is consistent with changes in the ground as the shield face progresses (the so-called "digital twin").

[0074] (effect) Next, the effects achieved by the face vicinity property measuring devices 6, 6A, 6B, 6C, 6D, and 6E of this embodiment will be listed and explained.

[0075] (1) As described above, the face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) of this embodiment is a face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) used in an earth pressure type shield 1 as a shield machine among tunnel boring machines, and includes an exploration tool 61 that is stored in the shield machine, reaches the face vicinity FA, ​​and abuts or penetrates the face vicinity, a jack 62 as an advancing and retreating means for moving the exploration tool 61 back and forth between the shield machine and the face vicinity FA, ​​and a displacement sensor 66 that detects the displacement of the exploration tool 61. Therefore, at any measurement position, the property near the face can be accurately detected based on the actual measurement value.

[0076] That is, since the tip of the detecting jig 61 reaches the FA near the face and abuts against or penetrates the FA near the face, the displacement near the face can be directly and accurately reflected by the detecting jig 61. In this case, since the distance from the partition 3 to the face F (i.e., the tip of the cutter bit 52) ​​is known in advance, the detecting jig 61 can be accurately pressed against or penetrated into the FA near the face.

[0077] (2) Furthermore, the near-face property measuring devices 6, 6A are preferably configured such that the exploration tool 61 is stored in a fixed mixing blade 55 that protrudes from the partition wall 3 of the tunnel boring machine into the chamber 16, and the tip of the fixed mixing blade 55 reaches the near-face FA. Because the fixed mixing blade 55 protrudes from the partition wall 3 into the chamber 16 toward the face F, the stroke of the exploration tool 61 to the near-face FA can be shortened accordingly.

[0078] Therefore, the displacement of the FA near the face can be measured more accurately by the detection jig 61. In other words, since the distance from the tip of the fixed mixing blade 55 to the FA near the face is shorter than the distance from the surface of the partition 3 to the FA near the face, the distance traveled by the detection jig 61 when moving back and forth within the chamber 16 can be shortened. Furthermore, since the required stroke is reduced, the size of devices such as the jack 62 for sliding the detection jig 61 back and forth can be reduced. Since the interior behind the partition 3 of the shield is narrow, it is advantageous to reduce the size of the device.

[0079] (3) Furthermore, in the face vicinity property measuring device 6A, the jack 62 as the advancing / retracting means is preferably configured to be composed of a cylinder portion 62a and a rod portion 62b, and is stored in the fixed mixing blade 55, and the rod portion 62b is preferably configured to be used also as the exploration jig 61 and to reach from the tip of the fixed mixing blade 55 to the face vicinity FA. By configuring in this way, the length of the advancing / retracting means (i.e., the jack 62) protruding toward the tunnel mouth side inside the shield machine can be further shortened. In other words, the protruding amount of the jack 62 inside the shield machine can be reduced by the protruding length of the fixed mixing blade 55 into the chamber 16.

[0080] (4) Furthermore, it is preferable that the jack 62 as the advancing / retracting means of the tunnel face vicinity property measuring device 6C is composed of a cylinder portion 62a and a rod portion 62b, and further includes a second jack 69 as a machine inside advancing / retracting means for advancing / retracting the cylinder portion 62a from the partition wall 3 of the tunnel excavator into the chamber 16. In this way, the jack 62 itself is configured to be slidable back and forth, rather than being stored in the fixed mixing blade 55, thereby reducing obstacles in the chamber 16. In other words, the amount of protrusion into the machine can be reduced by dividing the required stroke into two stages. During excavation, the fixed mixing blade does not protrude into the chamber 16, and deformation and damage of the tunnel face vicinity property measuring device 6C due to the gravel being caught in the excavated ground can be prevented.

[0081] In addition, the face vicinity property measuring devices 6B, 6D, and 6E are preferably configured such that the exploration tool 61 is stored in the cutter spoke 51 of the tunnel boring machine and reaches the face vicinity FA from the cutter spoke 51. In this way, by installing the exploration tool 61 and the jack 62 in the cutter spoke 51, the required stroke to the face vicinity FA can be extremely short, so that the face vicinity property measuring device 6 itself becomes very short. Therefore, the exploration tool 61 and the jack 62 can be arranged inside the cutter spoke 51. In this way, if the measuring device is stored in the cutter spoke 51, the face vicinity property measuring device 6 can be arranged in a narrow place in the shield machine. In addition, since the face vicinity property measuring device 6 can be moved by rotating the cutter head 5, it is possible to measure at any point on a certain radius circle from the shield center.

[0082] (5) Furthermore, although not shown, the detection tool (61) is preferably configured to be stored in the cutter head face plate, intermediate beam, and / or connecting material of the tunnel boring machine and to reach the face. In this way, by installing the detection tool 61 near the face, the required stroke to the face vicinity FA can be made extremely short, and the length of the face vicinity property measuring device is also very short. Therefore, the detection tool 61 can be stored inside the machine.

[0083] (6) Moreover, it is preferable that the cutter spokes 51 have a (movable) stirring blade 54 or a storage box 54A on the rear side, and at least a part of the detection jig 61 or the jack 62 is stored in the (movable) stirring blade 54 or the storage box 54A. When the near-face property measuring device 6 is larger than the depth of the cutter spokes 51, it can be placed inside by utilizing the (movable) stirring blade 54 or the storage box 54A arranged behind the cutter spokes 51. In this case, the hydraulic oil line for driving the jack 62 and the signal line from the displacement sensor 66 are led into the shield machine behind the bulkhead 3 through the center shaft (cutter rotation shaft 10).

[0084] In this modified example, the measuring device 6 for properties near the tunnel face is housed inside the cutter spokes 51, so there is no need to place the measuring device in a narrow space inside the shield machine. In addition, the measuring device can be moved by rotating the cutter head 5, so it is possible to measure at any point on a circle of a certain radius from the center of the shield.

[0085] Furthermore, the face vicinity property measuring devices 6D, 6E further include a pressure gauge 22A for measuring the earth pressure at the face vicinity FA or a water pressure gauge 23A for measuring the pore water pressure at the face vicinity FA in the exploration jig 61, so that by measuring the earth pressure and pore water pressure in addition to the displacement, it becomes possible to analyze the properties around the face (ground rock) in more detail and more accurately.

[0086] In addition, the face vicinity property measuring device 6E has the same cross-sectional shape from the tip to the rear of the exploration jig 61, so it is easy to penetrate into the face vicinity FA with a small load, and the range of options for the advancement and retreat structure can be expanded. In addition, it is possible to prevent the erroneous intake of soil and sand when storing the exploration jig. And, since there are measuring devices at the approximate center and side of the tip of the exploration jig 61, it is possible to simultaneously measure the face properties near the face and inside the chamber.

[0087] (7) Furthermore, since the tip of the exploration jig 61 is a cutter bit 52, if the exploration jig 61 is configured to be extended to the position FA near the face before stopping excavation, it is possible to ensure that the exploration jig 61 abuts against the face even in hard ground that is difficult to penetrate.

[0088] (8) Furthermore, by further providing an in-chamber pressure gauge 22A for measuring the pressure within the chamber 16 of the earth pressure shield 1 as a tunnel boring machine, and / or an in-chamber water pressure gauge 23A for measuring the pore water pressure within the chamber 16, it becomes possible to analyze the properties within the chamber 16 in more detail and more accurately by measuring the pressure and pore water pressure in addition to the displacement.

[0089] (9) The system S for setting the controlled earth pressure in this embodiment is a system S for setting the controlled earth pressure in the earth pressure shield 1 as a tunnel boring machine, and includes a pressure gauge 22 for measuring the mud pressure in the chamber 16, an earth removal device 17 as a mud pressure changing means for changing the mud pressure in the chamber 16, a face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) for measuring the displacement of the face vicinity FA, ​​an analysis unit 41 for analyzing the deformation characteristics of the ground based on the measured mud pressure, the measured displacement of the face vicinity FA, ​​and the measured pore water pressure of the face vicinity FA, ​​and a setting unit 42 for setting the controlled earth pressure based on the analyzed deformation characteristics. Because of this configuration, the system S for setting the controlled earth pressure can set the controlled earth pressure by directly measuring the relationship between the mud pressure in the chamber and the displacement near the face, rather than setting the controlled earth pressure based on assumptions or estimates.

[0090] (10) Furthermore, when the tunnel boring machine is stopped, a small amount of mud is discharged by the soil discharge device 17 as a mud pressure changing means, thereby reducing the mud pressure in the chamber 16, and the active earth pressure can be found from the deformation of the ground by the analysis unit 41. Therefore, when the shield machine stops excavating - for example, when the segments are being assembled - the pressure inside the chamber 16 is slightly reduced to slightly displace the FA near the face toward the chamber 16, and the active earth pressure can be directly found by analyzing the yield point from the transition region in the graph showing the relationship between the mud pressure and the amount of displacement near the face.

[0091] (11) In addition, the analysis unit 41 estimates the mechanical constants of the ground by inverse analysis based on the analyzed deformation characteristics of the ground, updates the FEM model using the estimated mechanical constants of the ground, and predicts the impact on the surrounding ground and / or structures using the updated FEM model. Therefore, although not completely in real time, by updating the FEM model at intervals that are close to real time updates and much shorter than conventional intervals, the characteristics of the ground can be made much closer to the actual characteristics. Therefore, prediction and impact assessment using the FEM model can be realized with extremely high accuracy.

[0092] Although the embodiments and modifications of the present invention have been described in detail above with reference to the drawings, the specific configurations are not limited to these embodiments and modifications, and design changes that do not deviate from the gist of the present invention are included in the present invention.

[0093] For example, in the embodiment and the modified examples, the face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) has been described as being installed at a predetermined position, but the present invention is not limited to this. For example, in the embodiment and the first and third modified examples, the measuring device may be installed midway between the shield center and the hood part of the bulkhead 3 as shown in the figure, or may be installed closer to the hood part. In the second modified example, the measuring device may be installed at the middle position of the cutter spokes 51 as shown in the figure, or may be installed near the shield center or near the tip of the cutter spokes 51. The measuring device may also be attached outward on the outermost circumference of the cutter spokes 51. Furthermore, the measuring device may be installed on the cutter head face plate or intermediate beam connecting member.

[0094] Furthermore, although not shown in the drawings, the measuring device for properties near the face may be installed in a cutter head component such as a cutter head face plate, an intermediate beam, and / or a connecting member. In this case, the cutter head face plate, the intermediate beam, the connecting member, etc. constitute a part of the cutter head.

[0095] In the embodiment, the setting system S for controlled earth pressure using the face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E) has been described, but the present invention is not limited to this. For example, the present invention can be used in a system for detecting looseness of the face using the face vicinity property measuring device 6 (6A, 6B, 6C, 6D, 6E). [Explanation of symbols]

[0096] 1: Earth pressure shield (tunnel boring machine) 2: Skin plate 2a: Hood section 2b: Tail section 3: Bulkhead 5: Cutter head 6: Measuring device for characteristics near the face (Example) 6A-6E: Face vicinity property measuring device (modified) 10: Cutter rotation axis 11: Bearings 12: Cutter drive unit 13: Gearbox 14: Rotation drive source 15: Erector 16: Chamber 17:Earth removal equipment 18: Shield propulsion jack 19: Tail seal 21:Soil supply piping 22, 22A: Pressure gauge 23, 23A: Water pressure gauge 40: Control section 41:Analysis Department 42: Setting section 43: Communication cable 51: Cutter Spoke 52: Cutter Bit 53: Fishtail bit 54: (moving) stirring blade 54A: Storage box 55: Fixed mixing blade 55A: Storage box 61: Inspection tool 610: Tip 611a: Cone section 611b: Arrow section 611c: Drill section 612: flange 613: Main body 62: Jack 62a: Cylinder section 62b: Rod section 63: Hydraulic chuck 64: Detection unit 65: Guide 66: Displacement sensor 67: Water stop device 68: Valve (ball valve) 68A: Valve (ball valve) 68B: Release device (hydraulic chuck) 69: Second jack (machine interior advance / retract means) 70: Bracket 90 :Segment S: Controlled earth pressure setting system F: Face FA: Near the face

Claims

1. A tunnel face vicinity property measuring device used in a tunnel boring machine, A detection tool that is stored in the tunnel boring machine and reaches a position near the tunnel face; an advancing / retracting means for advancing / retracting the detection tool between inside the tunnel boring machine and a position near the tunnel face; A displacement sensor that detects the displacement amount of the exploration jig, a pressure gauge that measures the earth pressure near the face, and / or a water pressure gauge that measures the pore water pressure near the face, The exploration tool is stored in a fixed mixing blade or a storage box that protrudes from a partition wall of the tunnel boring machine into a chamber, and is configured to reach from a tip of the fixed mixing blade or the storage box to a face; The advancing and retreating means is composed of a cylinder section and a rod section, and is stored within the fixed agitator or within the storage box, and the rod section is configured to double as the exploration tool and reach from the tip of the fixed agitator or the storage box to the face, in this device for measuring properties near the face.

2. A tunnel face vicinity property measuring device used in a tunnel boring machine, A detection tool that is stored in the tunnel boring machine and reaches a position near the tunnel face; an advancing / retracting means for advancing / retracting the detection tool between inside the tunnel boring machine and a position near the tunnel face; A displacement sensor that detects the displacement amount of the exploration jig, a pressure gauge that measures the earth pressure near the face, and / or a water pressure gauge that measures the pore water pressure near the face, The advancing and retreating means is composed of a cylinder portion and a rod portion, The device for measuring properties near the tunnel face further comprises an inside-machine advancing / retracting means for moving the cylinder portion back and forth from the partition wall of the tunnel boring machine into the chamber.

3. A tunnel face vicinity property measuring device used in a tunnel boring machine, A detection tool that is stored in the tunnel boring machine and reaches a position near the tunnel face; an advancing / retracting means for advancing / retracting the detection tool between inside the tunnel boring machine and a position near the tunnel face; A displacement sensor that detects the displacement amount of the exploration jig, a pressure gauge that measures the earth pressure near the face, and / or a water pressure gauge that measures the pore water pressure near the face, The detection jig is stored in the cutter head face plate portion and / or intermediate beam of the tunnel boring machine and is configured to reach the face of the tunnel, thereby providing a device for measuring properties near the face.

4. A cutter spoke has a movable mixing blade or a storage box on the rear side, and at least a part of the detection jig or the advancing / retracting means is stored within the movable mixing blade or the storage box, as described in claim 3.

5. 4. The device for measuring properties near a face according to claim 3, wherein a tip of the detection jig is a cutter bit.

Images