Shield tunnel construction evaluation method and shield tunnel construction evaluation system

Abstract

To provide a shield tunnel construction evaluation method and a shield tunnel construction evaluation system capable of suppressing cost more than before.SOLUTION: The shield tunnel construction evaluation system 100 includes a three-dimensional measuring instrument 20 for measuring three-dimensional coordinates of an inner peripheral surface of a segment ring and an inner peripheral surface of a skin plate, and a shield tunnel construction evaluation device 40 for evaluating a construction state of the shield tunnel based on a measurement result of the three-dimensional measuring instrument 20. The shield tunnel construction evaluation device 40 obtains a tail clearance based on a first shape obtained by projecting a plurality of first measurement points on the inner peripheral surface of the skin plate onto an orthogonal plane orthogonal to the machine axis of the shield machine, a second shape obtained by projecting a plurality of second measurement points on the inner peripheral surface of the segment ring onto the orthogonal plane, and the thickness of the segment ring.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a shield tunnel construction evaluation method and a shield tunnel construction evaluation system. [Background technology]

[0002] One of the construction management items for shield tunneling is "tail clearance," which is the distance between the outer surface of the segments assembled inside the tail of the shield tunneling machine and the inner surface of the shield tunneling machine's steel shell (skin plate).

[0003] Conventionally, when shield tunneling or segment assembly is completed, workers move to a predetermined location and measure the tail clearance using a measuring tool (for example, a convex or vernier caliper). Regarding tail clearance measurement, there are techniques for measuring tail clearance using dedicated equipment (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-090363 [Patent Document 2] Japanese Patent Publication No. 2022-023632 Summary of the Invention [Problem to be solved by the invention]

[0005] In addition to tail clearance, there are several other items that must be managed during shield construction (one example is the roundness of the segment rings). This means that there are problems such as reduced construction efficiency due to workers having to measure each item individually, reduced safety due to measurement work being performed at high altitudes, and increased costs if measuring equipment is installed for each item.

[0006] From this perspective, the present invention provides a shield tunnel construction evaluation method and a shield tunnel construction evaluation system that can improve construction efficiency and safety and reduce costs compared to conventional methods. [Means for solving the problem]

[0007] The shield tunnel construction evaluation method according to the present invention is a method for evaluating the construction status of a shield tunnel. This shield tunnel construction evaluation method includes a skin plate coordinate measurement step, a segment ring coordinate measurement step, and a tail clearance calculation step. In the skin plate coordinate measurement process, a three-dimensional measuring device is used during excavation by the shield machine or when excavation is completed to measure the three-dimensional coordinates of multiple first measurement points on the inner surface of the skin plate corresponding to the segment ring to be assembled next. In the segment ring coordinate measurement step, the three-dimensional coordinates of a plurality of second measurement points on the inner peripheral surface of the segment ring are measured using the three-dimensional measuring device when the assembly of the next segment ring is completed. In the tail clearance calculation process, the tail clearance is calculated based on the apparent first shape of the inner surface of the skin plate obtained by projecting the first measurement point onto an orthogonal plane perpendicular to the machine axis of the shield tunneling machine, the apparent second shape of the inner surface of the segment ring obtained by projecting the second measurement point onto the orthogonal plane, and the thickness of the segment ring registered in advance.

[0008] In the shield tunnel construction evaluation method according to the present invention, information about the shape of the segment rings is obtained during the tail clearance calculation process, and this information can be used to calculate the circularity of the segment rings. In other words, it is possible to measure both the tail clearance and the circularity of the segment rings using a single three-dimensional measuring device. This reduces costs compared to having workers measure each of these control items separately or installing measuring equipment. Furthermore, because tail clearance can be measured continuously while excavating, fluctuations can be constantly monitored and reflected in the operation of the shield tunneling machine. This prevents segment assembly failure due to a decrease in tail clearance and segment damage due to contact with the skin plate.

[0009] The shield tunnel construction evaluation method may further include a segment roundness calculation step, in which the second measurement points projected onto the orthogonal plane are fitted to an ellipse by the least squares method, and an appropriate second shape is obtained by calculating the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of distances to the ellipse on lines connecting the projected second measurement points and the center of the ellipse is minimized, and the amount and direction of distortion are determined from the second shape.

[0010] The shield tunnel construction evaluation method may further include a skin plate shape calculation step in which the first measurement points projected onto the orthogonal plane are fitted to an ellipse by the least squares method, and an appropriate first shape is determined by calculating the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of the distances to the ellipse on the lines connecting the projected first measurement points and the center of the ellipse is minimized. In this case, in the tail clearance calculation process, a virtual third shape of the outer surface of the segment ring may be obtained by offsetting the second shape by the thickness of the segment ring, and the distance between the first shape and the third shape may be obtained as the tail clearance.

[0011] In the skin plate coordinate measuring step and the segment ring coordinate measuring step, measurements may be performed using a plurality of the three-dimensional measuring devices. In this case, the first measurement point and the second measurement point projected onto the orthogonal plane in the tail clearance calculation step are a combination of measurement results from the plurality of three-dimensional measuring devices.

[0012] A shield tunnel construction evaluation system according to the present invention is a system for evaluating the construction status of a shield tunnel, and includes a three-dimensional measuring device that measures the three-dimensional coordinates of the inner peripheral surfaces of the segment rings and the skin plates, and a shield tunnel construction evaluation device that evaluates the construction status of the shield tunnel based on the measurement results of the three-dimensional measuring device. The shield tunnel construction evaluation device includes a tail clearance calculation unit that calculates the tail clearance based on a first apparent shape of the inner peripheral surface of the skin plate obtained by projecting a plurality of first measurement points on the inner peripheral surface of the skin plate onto an orthogonal plane orthogonal to the machine axis of the shield machine, a second apparent shape of the inner peripheral surface of the segment ring obtained by projecting a plurality of second measurement points on the inner peripheral surface of the segment ring onto the orthogonal plane, and a pre-registered thickness of the segment ring.

[0013] In the shield tunnel construction evaluation system according to the present invention, information about the shape of the segment rings is obtained during the tail clearance calculation process, and this information can be used to calculate the circularity of the segment rings. In other words, it is possible to measure both the tail clearance and the circularity of the segment rings using a single three-dimensional measuring device. This reduces costs compared to having workers measure each of these control items separately or installing measuring equipment. Furthermore, because tail clearance can be measured continuously while excavating, fluctuations can be constantly monitored and reflected in the operation of the shield tunneling machine. This prevents segment assembly failure due to a decrease in tail clearance and segment damage due to contact with the skin plate.

[0014] The three-dimensional measuring device may be fixed to the shield machine by a fixture. The fixture may have, for example, a plate-shaped main body to which the three-dimensional measuring device is fixed and a fixing part that fixes the main body to the shield machine. Four mounting holes for attaching targets of a surveying instrument are formed around the periphery of the three-dimensional measuring device in the main body. The mounting holes are preferably arranged at equal distances to the three-dimensional measuring device and are arranged in a circle at 90-degree intervals. [Effects of the Invention]

[0015] According to the present invention, construction efficiency and safety can be improved and costs can be reduced compared to conventional methods. [Brief explanation of the drawings]

[0016] [Figure 1] This is an example of a shield tunneling machine, showing a cross section. [Figure 2] FIG. 2 is a cross-sectional view showing an example of a shield tunneling machine, corresponding to II-II in FIG. 1. [Figure 3] 1 is a configuration diagram of a shield tunnel construction evaluation system according to an embodiment of the present invention. [Figure 4] An image of the detection range of a 3D-LiDAR, where (a) is a perspective view and (b) is a cross-sectional view. [Figure 5] 1 shows an example of a fixture for a three-dimensional measuring device. (a) shows the fixture with the three-dimensional measuring device attached, and (b) shows the fixture with the three-dimensional measuring device and a target for position measurement attached. [Figure 6] 1 is a schematic configuration diagram of a shield tunnel construction evaluation device according to an embodiment of the present invention. [Figure 7] 1 is an example of a flowchart showing a preparation process of a shield tunnel construction evaluation method. [Figure 8] 1 is an example of a flowchart showing a measurement process of a shield tunnel construction evaluation method. [Figure 9]This is an illustration of three-dimensional coordinate measurement using a three-dimensional measuring device, where (a) shows the state at the start of excavation, (b) shows the state at the end of excavation, and (c) shows the state at the end of segment assembly. [Figure 10] FIG. 10 is an image diagram for explaining a process for deleting unnecessary point clouds. [Figure 11] FIG. 10 is an image diagram for explaining the necessary point cloud interpolation processing. [Figure 12] 10A and 10B are diagrams for explaining a calculation process of circularity; [Figure 13] FIG. 10 is a diagram for explaining a calculation process of a tail clearance. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Each drawing is merely a schematic illustration to allow a sufficient understanding of the present invention. Therefore, the present invention is not limited to the illustrated examples. In each drawing, common or similar components are designated by the same reference numerals, and redundant explanations thereof may be omitted.

[0018] <Configuration of a shield machine using the shield tunnel construction evaluation system according to the embodiment> With reference to Figures 1 and 2, a shield tunnel construction evaluation system according to an embodiment will be described below. Figures 1 and 2 show cross-sectional views of an example of a shield tunnel construction evaluation system 1. Figure 2 is a cross-sectional view corresponding to II-II in Figure 1. In the description of the shield tunnel construction machine 1, the tunnel excavation direction is set as the forward direction (forward movement direction), and up, down, left, and right are set. As shown in Figure 1, this embodiment will be described assuming an earth pressure type shield tunnel construction machine 1, but the type of shield tunnel construction machine 1 is not limited to this. In other words, the shield tunnel construction evaluation system can also evaluate construction work by shield tunnel construction machines using construction methods other than earth pressure type.

[0019] As shown in Figure 1, the shield machine 1 comprises a front body 3 and a rear body 4. The front body 3 and rear body 4 are connected by a bending jack 5. The bending jacks 5 are arranged at intervals around the circumference of the front body 3 (only the bending jacks arranged on the upper side of the shield machine 1 are shown in Figure 1). The bending jack 5 is a hydraulic jack made up of a cylinder and a rod that can move back and forth. Note that the shield machine 1 shown in Figure 1 is merely an example, and it may also be a single-body shield machine that does not have a bending jack 5 (bending mechanism).

[0020] As shown in Figure 1, the front body 3 has a cutter head 6. The cutter head 6 is a rotating part that excavates the natural ground and is located at the front end of the front body 3. The rear body 4 has a shield jack 7 and an erector 8. The shield jacks 7 are hydraulic jacks consisting of a cylinder and a retractable rod, and multiple shield jacks 7 are arranged at a predetermined pitch around the circumferential direction of the rear body 4 (Figure 2 shows only those arranged on the upper and lower sides of the shield machine 1). The erector 8 is a device that grips and rotates segments 9 to transport the segments 9 to a predetermined assembly position. The shield machine 1 excavates the natural ground by rotating the cutter head 6 and pressing the shield jacks 7 against the joint surface 10c of the segment ring 10 assembled at the rear, thereby obtaining propulsion force.

[0021] <Configuration of shield tunnel construction evaluation system according to the embodiment> The configuration of a shield tunnel construction evaluation system 100 according to an embodiment will be described with reference to Fig. 3. Fig. 3 is a configuration diagram of the shield tunnel construction evaluation system 100. The shield tunnel construction evaluation system 100 is a system for evaluating the construction status of a shield tunnel, and in this embodiment, evaluates the tail clearance and the roundness of the segment ring 10. The tail clearance is the distance between the inner peripheral surface 2a of the skin plate 2 in the tail portion of the rear body 4 and the outer peripheral surface 10b of the segment ring 10.

[0022] As shown in Fig. 3, the shield tunnel construction evaluation system 100 mainly comprises a three-dimensional measuring device 20, a joint box 30, and a shield tunnel construction evaluation device 40. The three-dimensional measuring device 20 and the shield tunnel construction evaluation device 40 can communicate via the joint box 30. The joint box 30 functions as an AC / DC converter for power supply and as a gigabit Ethernet hub.

[0023] The three-dimensional measuring device 20 shown in FIG. 3 is a sensor capable of detecting the distance to an object (the object's position) and the object's shape. The three-dimensional measuring device 20 is, for example, a 3D-LiDAR (Light Detection and Ranging) device, and this embodiment will be described assuming a 3D-LiDAR. The 3D-LiDAR has an emitting unit that emits laser light and a receiving unit that receives the laser light reflected from the object, and measures the time it takes for the laser light to hit the object and bounce back. The emitting unit of the 3D-LiDAR emits laser light, for example, at a specified angular interval of approximately 1 to 2 degrees vertically and at dense intervals of 0.1 to 0.4 degrees horizontally while rotating using a motor. This allows the 3D-LiDAR to have a planar detection range and can acquire the shape of the object as point cloud data. An image of the 3D-LiDAR's detection range is shown in FIG. 4. FIG. 4(a) is a perspective view, and FIG. 4(b) is a cross-sectional view.

[0024] In this embodiment, a three-dimensional measuring device 20 is used to detect (1) the inner peripheral surface 2a of the skin plate 2 in the tail portion of the rear body 4, and (2) the inner peripheral surface 10a of the segment ring 10. The three-dimensional measuring device 20 is fixed to the rear body 4 of the shield tunneling machine 1, and the position of the shield tunneling machine 1 relative to a reference point is measured in advance. The three-dimensional measuring device 20 detects the inner peripheral surface 2a of the skin plate 2 while the shield jack 7 is extended (the rod extends from the cylinder) from the start of excavation to the end of excavation. Meanwhile, the three-dimensional measuring device 20 detects the inner peripheral surface 10a of the segment ring 10 while the shield jack 7 is retracted (the rod is stored in the cylinder) from the completion of assembly of the segment ring 10 to the start of excavation.

[0025] Referring to FIG. 5, a fixture 50 for fixing the three-dimensional measuring device 20 will be described. FIG. 5 is an example of the fixture 50 for the three-dimensional measuring device 20, where (a) shows the three-dimensional measuring device 20 attached to the fixture 50, and (b) shows the three-dimensional measuring device 20 and a target 53 for position measurement attached to the fixture 50. With the target 53 attached as shown in FIG. 5(b), a surveying instrument is used to measure the position of the three-dimensional measuring device 20 relative to a reference point on the shield tunneling machine 1. Measurement with the three-dimensional measuring device 20 is performed, for example, before the shield tunneling machine 1 starts operating. Then, the target 53 is removed to return to the state shown in FIG. 5(a), and the three-dimensional measuring device 20 is operated while the shield tunneling machine 1 is operating to detect the shape of the target object.

[0026] 5(a) is for fixing the three-dimensional measuring device 20 to the shield machine 1 (assumed to be the rear body 4 in this embodiment). The fixing device 50 mainly comprises a main body portion 51 and a fixing portion 52.

[0027] The main body 51 is a rectangular (square in this embodiment) plate material. The three-dimensional measuring device 20 is fixed to the center of the main body 51 by a fixing means (for example, a screw), not shown. It is desirable that an orthogonal line perpendicular to the main body 51 and one of the axes of the coordinate system unique to the three-dimensional measuring device 20 are parallel. In this embodiment, the origin 20a of the coordinate system of the three-dimensional measuring device 20 is located at the center of the main body 51 and on the central orthogonal line 51a perpendicular to the main body 51.

[0028] The fixing parts 52 are used to fix the main body part 51 to the rear torso 4. In this embodiment, magnets are assumed as the fixing parts 52, and the fixing parts 52 fix the main body part 51 to the metal part of the rear torso 4 using magnetic force. The number and arrangement of the fixing parts 52 are not particularly limited, and it is preferable that they are in a number and arrangement that can maintain the main body part 51 in a stable fixed state. In this embodiment, the fixing parts 52 are placed on the rear surface of the main body part 51 (the surface opposite to the surface on which the three-dimensional measuring device 20 is installed), near each corner. When the fixing device 50 is fixed to the rear torso 4, it is preferable that the central axis of the rear torso 4 and the central orthogonal line 51a of the main body part 51 are parallel.

[0029] The main body 51 has a mounting hole 51b for mounting a target 53 (see FIG. 5(b)). As shown in FIG. 5(b), the target 53 has a prism 53a and a holder 53b that rotatably holds the prism 53a. The target 53 can orient the prism 53a toward a surveying instrument (not shown).

[0030] The number of mounting holes 51b is preferably three or more. By measuring three or more targets 53 attached to the fixture 50 using a surveying instrument, the position of the origin 20a of the three-dimensional measuring device 20 and the orientation (azimuth) of the coordinate system of the three-dimensional measuring device 20 can be determined. In this embodiment, a total of four mounting holes 51b are formed near the center of each side of the main body 51. In other words, the mounting holes 51b are arranged in a ring shape at 90-degree intervals. When viewed from above, the origin 20a of the coordinate system of the three-dimensional measuring device 20 is located at the intersection of two line segments connecting opposing mounting holes 51b (in other words, the intersection of two line segments connecting opposing mounting holes 51b is located on the center orthogonal line 51a of the main body 51). The distance from the mounting holes 51b to the origin 20a of the coordinate system is the same for all mounting holes 51b.

[0031] As shown in FIG. 5(b), targets 53 are attached to three of the four mounting holes 51b, and no target 53 is attached to the remaining one. By providing four mounting holes 51b in the main body 51, the fixing device 50 can be fixed to the shield tunneling machine 1 without having to consider the orientation of the main body 51. Another advantage is that the target 53 can be placed without having to consider the direction of the cable extending from the three-dimensional measuring device 20 or the presence of obstacles. For example, even if it is difficult to attach the target 53 to a specific mounting hole 51b due to the cable extending from the three-dimensional measuring device 20 or an obstacle, the target 53 can be attached to the remaining three mounting holes 51b.

[0032] The number and arrangement of the three-dimensional measuring devices 20 are not particularly limited, and it is preferable that they are in a number and arrangement that allows the shape of the inner peripheral surface 2a of the skin plate 2 and the inner peripheral surface 10a of the segment ring 10 to be properly measured using point cloud data acquired by the three-dimensional measuring device 20. It is preferable that the number and arrangement of the three-dimensional measuring devices 20 be determined taking into consideration the presence of obstacles (for example, the shield jack 7, the erector 8, the screw conveyor 12, etc.).

[0033] In this embodiment, as shown in FIG. 2, six three-dimensional measuring devices 20 are arranged in a ring shape inside the rear fuselage 4. The three-dimensional measuring devices 20 are fixed to the aft work deck 11, for example. By measuring the relative positions of each three-dimensional measuring device 20 in advance by surveying using targets 53 (see FIG. 5(b)), it is possible to combine the measurement results (here, point cloud data) of the six three-dimensional measuring devices 20 into one based on this positional relationship. In other words, by measuring the relative positions of each three-dimensional measuring device 20 in advance, it is possible to combine all point cloud data into one, so the positions at which the three-dimensional measuring devices 20 are installed can be freely selected.

[0034] 3 evaluates the construction status of a shield tunnel based on the detection results of the three-dimensional measuring device 20. In this embodiment, the shield tunnel construction evaluation device 40 evaluates the tail clearance and the roundness of the segment ring 10.

[0035] The shield tunnel construction evaluation device 40 is, for example, a personal computer (PC) or a server (including a cloud system configuration) connected to the personal computer so that it can communicate with the personal computer. In this embodiment, a personal computer is assumed to be installed in the driver's seat of the shield tunneling machine 1 and to be able to communicate with the three-dimensional measuring device 20 without going through the Internet. Since communication does not go through the Internet, high security can be achieved and problems such as communication failures can be avoided.

[0036] The configuration of the shield tunnel construction evaluation device 40 will be described with reference to Fig. 6. Fig. 6 is a schematic configuration diagram of the shield tunnel construction evaluation device 40. The shield tunnel construction evaluation device 40 mainly includes a memory unit 41, a control unit 42, a communication unit 43, an input unit 44, and an output unit 45.

[0037] The storage unit 41 is a component that stores information necessary for calculating the tail clearance and the roundness of the segment ring 10. The storage unit 41 is a storage medium such as a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a flash memory.

[0038] The storage unit 41 stores, for example, the thickness of the segment ring 10 (the thickness of the segment 9), an offset file, etc. The offset file is information for converting coordinate values ​​in one coordinate system to those in a different coordinate system. The offset file may contain, for example, the displacement amounts in the x-, y-, and z-axis directions and the rotation amounts (pitching, rolling, yawing) around the x-, y-, and z-axes of the origin of another coordinate system (second coordinate system, third coordinate system, etc.) relative to the reference coordinate system (first coordinate system). Note that a device other than the shield tunnel construction evaluation device 40 may have an offset file, and the converted coordinates may be acquired by the shield tunnel construction evaluation device 40.

[0039] By using the offset file, the position of the object can be converted as appropriate into, for example, the coordinate system of the three-dimensional measuring device 20, the machine coordinate system, the tunnel coordinate system, or the absolute coordinate system. The coordinate system of the three-dimensional measuring device 20 is a coordinate system having the three-dimensional measuring device 20 as its origin. The machine coordinate system is a coordinate system whose origin is an arbitrary point on the rear body 4 of the shield machine 1. The tunnel coordinate system is a local coordinate system with the x-axis in the direction of travel, the y-axis in the horizontal direction, and the z-axis in the vertical direction. The absolute coordinate system (plane rectangular coordinate system) is a coordinate system developed for surveying within Japan, and is the coordinate system adopted for public surveying in Japan.

[0040] The control unit 42 is a component that calculates and evaluates tail clearance and roundness through calculation processing. The control unit 42 is configured, for example, with a CPU (Central Processing Unit) and its peripheral devices, reads various processing programs, loads them into RAM, and performs various processes in cooperation with the programs. By executing the programs, the control unit 42 realizes functions such as a measurement result processing unit 42a, a skin plate roundness calculation unit 42b, a segment roundness calculation unit 42c, and a tail clearance calculation unit 42d. Note that only an overview of each function will be described here, and the details of each function will be described in the method explanation below.

[0041] Measurement result processing unit 42a is a function that processes the measurement results of three-dimensional measuring device 20. Measurement result processing unit 42a combines the measurement results (here, point cloud data) of multiple three-dimensional measuring devices 20 into one. Measurement result processing unit 42a also processes the measurement results (one example is deleting unnecessary point clouds and supplementing necessary point clouds) to make them easier to process in other functions.

[0042] The skin plate roundness calculation unit 42b projects multiple first measurement points on the inner surface 2a of the skin plate 2 onto an orthogonal plane perpendicular to the machine axis of the shield tunneling machine 1, thereby determining the apparent first shape of the inner surface 2a when viewed from the machine axis direction.

[0043] The segment circularity calculation unit 42c projects multiple second measurement points on the inner surface 10a of the segment ring 10 onto an orthogonal plane perpendicular to the machine axis of the shield tunneling machine 1, thereby determining the apparent second shape of the inner surface 10a when viewed from the machine axis direction.

[0044] The tail clearance calculation unit 42d calculates the tail clearance based on the apparent first shape of the inner circumferential surface 2a of the skin plate 2, the apparent second shape of the inner circumferential surface 10a of the segment ring 10, and the thickness of the segment ring 10. The tail clearance calculation unit 42d calculates an imaginary third shape of the outer circumferential surface 10b of the segment ring 10, for example, by offsetting the second shape by the thickness of the segment ring 10, and calculates the distance between the first shape and the third shape as the tail clearance.

[0045] The communication unit 43 is a component that realizes communication with other devices, apparatuses, systems, etc. (for example, the three-dimensional measuring device 20 and the operation management system of the shield tunneling machine 1). The communication unit 43 is configured by a network interface, etc.

[0046] The input unit 44 is a component that allows input of information and is configured by a keyboard equipped with various function keys, a pointing device equipped with various buttons (for example, a mouse or a touchpad), and the like.

[0047] The output unit 45 is a component that outputs the results and is configured with a display, a speaker, etc.

[0048] <Shield tunnel construction evaluation according to the embodiment> Shield tunnel construction evaluation using the shield tunnel construction evaluation system 100 will be described with reference to Figs. 7 and 8 (and Figs. 1 to 6 as appropriate). Shield tunnel construction evaluation mainly includes a preparation step S10 (see Fig. 6) and a measurement step S20 (see Fig. 7). Fig. 7 is an example of a flowchart showing the preparation step S10 of the shield tunnel construction evaluation. Fig. 8 is an example of a flowchart showing the measurement step S20 of the shield tunnel construction evaluation.

[0049] (Preparation step S10) The preparation step S10 shown in Figure 7 is carried out in advance as a step preceding the measurement step S20. The preparation step S10 may be carried out, for example, during initial excavation, or may be carried out at a predetermined timing during main excavation. In this embodiment, six three-dimensional measuring devices 20 are installed, and the preparation step S10 will be explained by focusing on one of them.

[0050] First, a person involved with the shield tunneling machine 1 (for example, a worker) considers the installation position of the three-dimensional measuring device 20 (step S11). The installation position of the three-dimensional measuring device 20 should be determined taking into consideration the presence of obstacles (for example, the shield jack 7, the erector 8, etc.).

[0051] Next, the worker installs the three-dimensional measuring device 20 at the position determined in step S11 (step S12). Specifically, the worker fixes the three-dimensional measuring device 20 to the fixture 50, and installs the integrated three-dimensional measuring device 20 and fixture 50 at the position determined in step S11. After the three-dimensional measuring device 20 and fixture 50 are installed, the wiring of the three-dimensional measuring device 20 is performed.

[0052] Next, the worker installs the target 53 (see FIG. 5(b)) in the fixture 50 (step S13). Specifically, the target 53 is installed in three of the four mounting holes 51b of the fixture 50. The three mounting holes 51b for installing the target 53 can be selected as appropriate, and it is preferable to select the mounting holes 51b depending on the situation at the site.

[0053] Next, the worker uses a surveying instrument to measure the coordinates of the prisms 53a of the target 53 (step S14). Specifically, the surveying instrument is installed in a position where it can collimate the prisms 53a of the target 53 attached to the fixture 50, and the three prisms 53a are measured using the surveying instrument. The shield tunnel construction evaluation device 40 obtains the results of measuring the prisms 53a using some means (one example is wireless communication from the surveying instrument). The surveying instrument determines the coordinate orientation of its own position using resection, so it can be installed either inside or outside the shield tunneling machine 1. When the surveying instrument is installed inside the shield tunneling machine 1, a temporary reference point is set during surveying. The positional relationship between the three-dimensional measuring instrument 20 and the three prisms 53a is known in advance (i.e., known) and is registered in advance in the shield tunnel construction evaluation device 40. This makes it possible to determine the position and orientation of the three-dimensional measuring instrument 20.

[0054] Next, the shield tunnel construction evaluation device 40 converts the position and orientation of the three-dimensional measuring device 20 determined in step S14 into machine coordinates (step S15). The worker also registers an offset file in the shield tunnel construction evaluation device 40 (step S16). The offset file here is used to convert the coordinate system of the three-dimensional measuring device 20 into the machine coordinate system. Next, the worker removes the target 53 from the fixture 50, leaving only the three-dimensional measuring device 20 (step S17). This completes the preparation process S10.

[0055] (Measurement process S20) The measurement step S20 shown in Fig. 8 is carried out as a step subsequent to the preparation step S10. The measurement step S20 is carried out, for example, during actual excavation.

[0056] The shield tunnel construction evaluation device 40 monitors the completion of excavation and the completion of assembly of the segment rings, and receives a signal when excavation and assembly are completed (step S21). When the shield tunnel construction evaluation device 40 receives these signals, it proceeds with the processing.

[0057] When receiving signals indicating completion of excavation and assembly, the shield tunnel construction evaluation device 40 cooperates with the operation management system of the shield tunneling machine 1 to acquire the necessary information (step S22). For example, the shield tunnel construction evaluation device 40 reads the segment assembly plan, stores the ring representative value, and grasps the jack stroke. The shield tunnel construction evaluation device 40 also cooperates with an automatic tracking surveying system to grasp the current position during excavation. The shield tunnel construction evaluation device 40 also grasps the position of the three-dimensional measuring device 20 from the jack stroke and the current position. The shield tunnel construction evaluation device 40 also acquires information on the position and type of the segment from the segment assembly plan and segment surveying history.

[0058] Next, three-dimensional measuring device 20 measures three-dimensional coordinates (step S23). For example, first three-dimensional measuring device 20 measures three-dimensional coordinates (step S23A), then second three-dimensional measuring device 20 measures three-dimensional coordinates (step S23B), and so on. Shield tunnel construction evaluation device 40 acquires the measurement results from three-dimensional measuring device 20.

[0059] Measurement of three-dimensional coordinates using the three-dimensional measuring device 20 will be described with reference to Figure 9. Figure 9 is an image diagram of measurement of three-dimensional coordinates using the three-dimensional measuring device 20, where (a) shows the state at the start of excavation, (b) shows the state at the completion of excavation, and (c) shows the state at the completion of segment assembly.

[0060] The area marked with the symbol P in Figure 9(a) indicates the detectable range of the three-dimensional measuring device 20 at the start of excavation. At the end of excavation, as shown in Figure 9(b), the detectable range expands by the amount of excavation, and an area marked with the symbol Q is added to the detectable range. The added detectable range Q corresponds to the segment ring 10 to be assembled next, and the three-dimensional coordinates of multiple first measurement points included in the detectable range Q are used to determine the apparent first shape of the inner surface 2a of the skin plate 2.

[0061] As shown in Figure 9(c), a new segment ring 10 is assembled in the detectable range Q, and the three-dimensional measuring device 20 performs measurements in the state shown in Figure 9(c), thereby obtaining the three-dimensional coordinates of the inner surface 10a of the newly assembled segment ring 10. The three-dimensional coordinates measured in the state shown in Figure 9(c) are used to determine the apparent second shape of the inner surface 10a of the segment ring 10.

[0062] Next, the measurement result processing unit 42a of the shield tunnel construction evaluation device 40 performs a synthesis process to synthesize the measurement results (point cloud data) from the three-dimensional measuring devices 20 (step S24). By measuring the relative positions of each three-dimensional measuring device 20 in advance, all point cloud data can be combined into one.

[0063] As shown in Fig. 10, the measurement result processing unit 42a may delete point clouds (point clouds within the range indicated by the dashed lines) that are not required for calculating the tail clearance and roundness. Fig. 10 is an image diagram for explaining the process of deleting unnecessary point clouds. Also, as shown in Fig. 11, if the measurement result processing unit 42a is unable to detect necessary point clouds for some reason, it may complement the point clouds using surrounding information. Fig. 11 is an image diagram for explaining the process of complementing necessary point clouds.

[0064] 8, following step S25, the shield tunnel construction evaluation device 40 converts the measurement results of the three-dimensional measuring device 20 into absolute coordinates (step S25). Then, if a signal indicating excavation completion has been received in step S21, the skin plate roundness calculation unit 42b of the shield tunnel construction evaluation device 40 calculates the roundness of the inner circumferential surface 2a of the skin plate 2 (step S26). On the other hand, if a signal indicating assembly completion has been received in step S21, the segment roundness calculation unit 42c of the shield tunnel construction evaluation device 40 calculates the roundness of the inner circumferential surface 10a of the segment ring 10 (step S27).

[0065] The roundness calculation process will be described with reference to FIG. 12. FIG. 12 is a diagram for explaining the roundness calculation process. The skin plate roundness calculation unit 42b projects multiple first measurement points on the inner circumferential surface 2a of the skin plate 2 onto an orthogonal plane perpendicular to the machine axis of the shield machine 1. The skin plate roundness calculation unit 42b also fits the first measurement points projected onto the orthogonal plane to an ellipse using the least squares method. As shown in FIG. 12, the skin plate roundness calculation unit 42b then calculates the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of the distances to the straight lines connecting the projected first measurement points and the center of the ellipse is minimized, thereby obtaining an appropriate first shape. The major axis angle is the angle between the major axis (the point at which the diameter of the ellipse is longest) and the horizontal.

[0066] The processing by the segment circularity calculation unit 42c is similar to the processing by the skin plate circularity calculation unit 42b. In the processing by the segment circularity calculation unit 42c, a plurality of second measurement points on the inner circumferential surface 10a of the segment ring 10 are projected onto an orthogonal plane perpendicular to the machine axis of the shield machine 1. The segment circularity calculation unit 42c also fits the second measurement points projected onto the orthogonal plane to an ellipse using the least squares method. Then, as shown in FIG. 12, the segment circularity calculation unit 42c calculates the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of the distances to the straight-line ellipse connecting the projected second measurement points and the center of the ellipse is minimized, thereby obtaining an appropriate second shape.

[0067] As shown in Figure 8, when the assembly of the segment ring 10 is completed, the tail clearance calculation unit 42d of the shield tunnel construction evaluation device 40 calculates the tail clearance based on the shape of the inner surface 2a of the skin plate 2 obtained in step S26 and the shape of the inner surface 10a of the segment ring 10 obtained in step S27 (step S28).

[0068] The tail clearance calculation process will be described with reference to FIG. 13. FIG. 13 is a diagram for explaining the tail clearance calculation process. The tail clearance calculation unit 42d calculates the tail clearance based on an apparent first shape of the inner circumferential surface 2a of the skin plate 2 calculated by projecting the first measurement points onto an orthogonal plane orthogonal to the machine axis of the shield machine 1, an apparent second shape of the inner circumferential surface 10a of the segment ring 10 calculated by projecting the second measurement points onto the orthogonal plane, and the pre-registered thickness of the segment ring 10. Specifically, the tail clearance calculation unit 42d calculates a virtual third shape of the outer circumferential surface 10b of the segment ring 10 by offsetting the second shape by the thickness of the segment ring 10. The tail clearance calculation unit 42d then calculates the intersections of vectors extending from the machine center axis in the up, down, left, right, and diagonal directions (which may include oblique directions) with the first shape and the third shape, and calculates the distance between the two points as the tail clearance.

[0069] Then, the shield tunnel construction evaluation device 40 displays the calculated circularity and tail clearance on the output unit 45. This completes the measurement step S20.

[0070] As described above, the shield tunnel construction evaluation system 100 according to this embodiment obtains information about the shape of the segment ring 10 during the tail clearance calculation process, and this information can be used to calculate the roundness of the segment ring 10. In other words, it is possible to measure both the tail clearance and the roundness of the segment ring 10 using a single three-dimensional measuring device 20. This reduces costs compared to having workers measure each of these control items individually or installing separate measuring devices. Furthermore, because the tail clearance can be measured continuously while excavating, fluctuations can be constantly monitored and reflected in the operation of the shield machine 1. This prevents segment assembly failure due to a decrease in tail clearance and segment damage due to contact with the skin plate.

[0071] Although the embodiments of the present invention have been described above, the present invention is not limited to these and can be practiced within the scope of the claims. For example, in the embodiment, the first and second measurement points projected onto an orthogonal plane are fitted to an ellipse using the least squares method. However, the first and second measurement points projected onto an orthogonal plane may be fitted to a shape other than an ellipse (such as a circle or polygon). It is preferable to use the approximation that maximizes the coefficient of determination (correlation coefficient). [Explanation of symbols]

[0072] 1. Shield tunneling machine 2 Skin Plate 3 Front body 4 Rear fuselage 5. Center-bending jack 6 cutter head 7 Shield Jack 8 Erector 9 segments 10 segment ring 11 Aft work deck 12 Screw conveyor 20 Three-dimensional measuring instrument 30 Joint Box 40 Shield tunnel construction evaluation device 41 Storage section 42 Control Unit 42a Measurement result processing section 42b Skin plate roundness calculation section 42c Segment roundness calculation section 42d Tail clearance calculation section 43 Communications Department 44 Input section 45 Output section 50 Fixtures 51 Main body 52 Fixed part 53 Target 53a Prism 53b Holding part 100 Shield Tunnel Construction Evaluation System

Claims

1. A shield tunnel construction evaluation method for evaluating the construction status of a shield tunnel, comprising: a skin plate coordinate measurement process in which, using a three-dimensional measuring device during or after the shield machine has excavated, the three-dimensional coordinates of a plurality of first measurement points on the inner peripheral surface of the skin plate corresponding to the segment ring to be assembled next are measured; a segment ring coordinate measurement step of measuring three-dimensional coordinates of a plurality of second measurement points on the inner peripheral surface of the segment ring using the three-dimensional measuring device when the assembly of the segment ring is completed; a tail clearance calculation step of calculating a tail clearance based on a first apparent shape of the inner peripheral surface of the skin plate obtained by projecting the first measurement points onto an orthogonal plane orthogonal to the machine axis of the shield machine, a second apparent shape of the inner peripheral surface of the segment ring obtained by projecting the second measurement points onto the orthogonal plane, and a pre-registered thickness of the segment ring. A shield tunnel construction evaluation method characterized by:

2. The method further includes a segment circularity calculation step of fitting the second measurement points projected onto the orthogonal plane to an ellipse by the least squares method, calculating the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of the distances to the ellipse along lines connecting the second measurement points after projection and the center of the ellipse is minimized, thereby obtaining an appropriate second shape, and determining the amount and direction of distortion from the second shape.

2. The shield tunnel construction evaluation method according to claim 1 .

3. a skin plate shape calculation step of fitting the first measurement points projected onto the orthogonal plane to an ellipse by the least squares method, and calculating the center, major axis, minor axis, and major axis angle of the ellipse so that the sum of squares of distances to the ellipse on straight lines connecting the first measurement points after projection and the center of the ellipse is minimized, thereby determining an appropriate first shape; In the tail clearance calculation step, a virtual third shape of the outer peripheral surface of the segment ring is obtained by offsetting the second shape by an amount corresponding to the thickness of the segment ring, and a distance between the first shape and the third shape is obtained as the tail clearance.

3. The shield tunnel construction evaluation method according to claim 2.

4. In the skin plate coordinate measuring step and the segment ring coordinate measuring step, measurements are performed using a plurality of the three-dimensional measuring devices, the first measurement points and the second measurement points projected onto the orthogonal plane in the tail clearance calculation step are obtained by combining measurement results of the plurality of three-dimensional measuring devices.

2. The shield tunnel construction evaluation method according to claim 1 .

5. A shield tunnel construction evaluation system for evaluating the construction status of a shield tunnel, a three-dimensional measuring device that measures three-dimensional coordinates of the inner peripheral surface of the segment ring and the inner peripheral surface of the skin plate; a shield tunnel construction evaluation device that evaluates the construction status of the shield tunnel based on the measurement results of the three-dimensional measuring device, The shield tunnel construction evaluation device is a tail clearance calculation unit that calculates a tail clearance based on a first apparent shape of the inner peripheral surface of the skin plate obtained by projecting a plurality of first measurement points on the inner peripheral surface of the skin plate onto an orthogonal plane orthogonal to the machine axis of the shield machine, a second apparent shape of the inner peripheral surface of the segment ring obtained by projecting a plurality of second measurement points on the inner peripheral surface of the segment ring onto the orthogonal plane, and a pre-registered thickness of the segment ring. A shield tunnel construction evaluation system characterized by:

6. the three-dimensional measuring device is fixed to the shield tunneling machine by a fixture, the fixture has a plate-shaped main body portion to which the three-dimensional measuring device is fixed, and a fixing portion that fixes the main body portion to the shield machine, The main body has four mounting holes formed around the periphery of the three-dimensional measuring device for mounting targets of a surveying instrument.

6. A shield tunnel construction evaluation system according to claim 5.

7. The mounting holes are arranged at equal distances to the three-dimensional measuring device and are arranged in a circle at 90-degree intervals.

7. A shield tunnel construction evaluation system according to claim 6.

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