Inner space displacement measurement system and inner space displacement measurement method

Abstract

To provide an internal displacement measurement system and method to improve the accuracy of measuring internal displacement in tunnels.SOLUTION: The present invention provides an internal displacement measurement system 100 that is disposed on a jig fixed to the wall surface of a tunnel 4 and includes a plurality of laser rangefinders that irradiate the wall surface of the tunnel 4 with a laser, and a processing device 1 that includes a measurement unit 11 that analyzes distance data indicating the distance between the laser rangefinder and the laser irradiation position to measure the amount of internal displacement of the tunnel 4. The laser rangefinders may include an angle detection unit (e.g., an inclinometer or an encoder) that detects the irradiation angle of the laser rangefinders, and the processing device 1 may include an angle correction unit 12 that performs angle correction for the amount of internal displacement using the irradiation angle detected by the angle detection unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an internal space displacement measurement system and an internal space displacement measurement method. [Background technology]

[0002] In recent years, there has been active development of technology related to surveying used in tunnel construction, and inventions related to surveying for measuring displacement inside a tunnel are also known. For example, Patent Document 1 discloses a method for measuring displacement of a tunnel shape. The invention of Patent Document 1 performs a tunnel shape measurement method including a distance measurement step in which laser light emitted from the origin of a distance measurement means is sequentially emitted onto the inner surface of the tunnel at predetermined angles, and the laser light reflected at the irradiation point on the inner surface of the tunnel is detected at the origin, thereby sequentially measuring the distance between the origin and the irradiation point at each predetermined angle; a cross-sectional data creation step in which position data of the multiple irradiation points is calculated based on the measurement results of the distance measurement step, using a predetermined reference point as a reference, to create cross-sectional data of the tunnel shape; and a cross-sectional data correction step in which the position data of the multiple irradiation points included in a predetermined area to which the position data of the target irradiation point belongs is averaged to calculate corrected position data, thereby correcting the cross-sectional data of the tunnel shape by performing this operation for a predetermined multiple of the irradiation points, and creating the corrected cross-sectional data at multiple time points, and comparing the corrected cross-sectional data at the multiple time points to detect displacement of the tunnel shape. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-65755 Summary of the Invention [Problem to be solved by the invention]

[0004] In the invention of Patent Document 1, the distance measuring device is installed on the road surface inside the tunnel, rotates around the origin in the circumferential direction of the tunnel, and irradiates the inner surface of the tunnel with a laser beam at a predetermined angle. However, because the distance measuring device rotates around the entire circumference, there is a risk that the irradiation position of the laser beam may shift slightly even if the irradiation angle setting remains the same. As a result, there is a problem in that it is not possible to improve the accuracy of the measurement results of the displacement of the tunnel shape.

[0005] From this perspective, an object of the present invention is to propose an internal displacement measurement system and an internal displacement measurement method that improve the measurement accuracy of internal displacement in a tunnel. [Means for solving the problem]

[0006] The present invention, which solves the above problem, is an internal displacement measurement system that is arranged on a jig fixed to the wall of a tunnel and includes a plurality of laser rangefinders that irradiate the wall of the tunnel with a laser, and a processing device that includes a measurement unit that analyzes distance data indicating the distance between the laser rangefinder and the laser irradiation position to measure the amount of internal displacement of the tunnel. The present invention also provides an internal displacement measurement method comprising the steps of: a step in which a plurality of laser rangefinders arranged on a jig fixed to the wall of a tunnel irradiate the wall of the tunnel with a laser; and a step in which a measurement unit of a processing device analyzes distance data indicating the distance between the laser rangefinders and the laser irradiation position, and measures the amount of internal displacement of the tunnel. According to the present invention, fixed-point observation can be achieved at the corresponding irradiation positions by laser irradiation without rotating each of the multiple laser range finders. Therefore, once the irradiation position is set, it will not shift due to the operation of the laser range finder, and the measurement accuracy of the displacement inside the tunnel can be improved.

[0007] Preferably, the laser rangefinder includes an angle detection unit that detects an irradiation angle of the laser rangefinder, and the processing device includes an angle correction unit that performs angle correction of the amount of internal displacement using the irradiation angle detected by the angle detection unit. In particular, it is preferable to perform multiple cross-section measurements using multiple types of horizontal irradiation angles as the irradiation angle. As a result, even if the attitude of the laser range finder disposed on the jig is changed as needed due to the presence of an obstacle or the like, the amount of internal displacement at the corresponding irradiation position can be accurately measured.

[0008] Preferably, the processing device further includes a setting unit that sets settings related to the laser rangefinder, and a display control unit that controls the display of the change over time in the amount of internal displacement measured by the measurement unit. This allows you to set or change the exposure time, measurement pitch, etc. for the laser rangefinder. It also allows you to visually grasp the change in the amount of internal air displacement over time. Therefore, it is possible to display the change in the amount of internal air displacement over time when using a laser rangefinder with changed settings, and to optimize the settings of the laser rangefinder based on the change in the amount of internal air displacement over time.

[0009] It is also preferable that the jig has a vibration-isolating section that is in close contact with the wall surface of the tunnel, and that the laser range finder be connected to the vibration-isolating section. This allows the vibration-damping performance of the jig to be maximized.

[0010] It is also preferable that the measurement unit analyzes the laser reflected from the irradiation position, outputs measurement quality as the analysis result, and performs filtering processing on the measurement values ​​obtained from the laser rangefinder using the output measurement quality. This makes it possible to exclude measurement values ​​whose measurement quality is below a predetermined threshold, thereby improving measurement accuracy.

[0011] It is also preferable that the system further includes one or more targets attached to the jig and a total station placed inside the tunnel, and that the targets are used to provide coordinates for each of the laser rangefinders and the irradiation position. This allows for improved measurement accuracy of tunnel interior displacement using the coordinates of the laser rangefinder and the coordinates of the irradiation position. Also, by observing changes in the coordinates over time, it is possible to monitor whether or not there is any misalignment of the jig or laser rangefinder. [Effects of the Invention]

[0012] According to the present invention, the measurement accuracy of the displacement inside a tunnel can be improved. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a functional configuration diagram of the internal space displacement measurement system of the present embodiment. [Figure 2] FIG. 1 is an explanatory diagram of multiple cross-section measurements for a shield tunnel. [Figure 3] FIG. 10 is an explanatory diagram of single-section measurement using a divided arrangement for a shield tunnel. [Figure 4] FIG. 1 is an explanatory diagram of single-section measurement for a mountain tunnel. [Figure 5] FIG. [Figure 6] 3 is a flowchart showing the process of the method for measuring displacement in the interior of the present embodiment. [Figure 7] This is the main screen for monitoring the amount of internal displacement for mountain tunnels. [Figure 8] This is the main screen for monitoring the amount of internal displacement of a shield tunnel. [Figure 9] 10 is an example of a graph showing a change over time in the amount of inner space displacement. DETAILED DESCRIPTION OF THE INVENTION

[0014] 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 will be omitted.

[0015] [composition] FIG. 1 is a functional configuration diagram of an internal displacement measurement system according to this embodiment. The internal displacement measurement system 100 is a system that detects changes in the interior of a tunnel due to tunnel excavation or the like. The internal displacement measurement system 100 includes a processing device 1, a measuring device 2, and a control device 3. FIG. 1 shows an example of single-section measurement of a shield tunnel (hereinafter referred to as tunnel 4). Single-section measurement is a method of setting multiple measurement cross sections 5 along the extension direction of the tunnel 4 and measuring the shape of each cross section 5. The measuring device 2 and the control device 3 are disposed, for example, on the wall surface of the tunnel 4. Furthermore, the measuring device 2 and the control device 3 are disposed for each cross section 5. The processing device 1 may be disposed, for example, in a control room (not shown) provided in the tunnel, or in an office (not shown) away from the construction site. The location of the processing device 1 is not limited to these.

[0016] The processing device 1 is a computer equipped with hardware such as an input unit, an output unit, a control unit, and a storage unit. For example, if the control unit is composed of a CPU (Central Processing Unit), information processing by a computer including the control unit is realized by program execution processing by the CPU. Furthermore, a storage unit included in the computer stores various programs for realizing the functions of the computer in response to instructions from the CPU. This realizes collaboration between software and hardware. The programs can be provided by recording them on a recording medium or via a network. The storage unit may also be implemented as a cloud. A console can be communicatively connected to the processing device 1, and the console can display the processing contents of the processing device 1. For example, the console can display image data generated by image processing by the processing device 1 on a screen.

[0017] The measuring device 2 is equipped with multiple laser range finders. The laser range finders are devices that irradiate the wall surface of the tunnel 4 with a laser and measure the distance to the laser irradiation position. Each laser range finder irradiates a predetermined circumferential position on the cross section 5 corresponding to the measuring device 2 on which it is mounted. The posture of the laser range finder, once the irradiation position is determined, is fixed. Therefore, fixed-point distance observation is performed for each laser range finder. For example, the laser range finder is disposed on a jig fixed to the wall surface of the tunnel 4 (details will be described later). Therefore, the laser range finder is disposed near the wall surface of the tunnel 4. The location of the laser range finder can be changed as appropriate. The laser rangefinder also includes an inclinometer (angle detection unit). The inclinometer detects the vertical irradiation angle (pitch angle) of the laser. The vertical irradiation angle is the irradiation angle with respect to a horizontal plane. The inclinometer may be built into the laser rangefinder or attached externally to the laser rangefinder. The laser rangefinder also includes an encoder. The encoder detects the horizontal irradiation angle (yaw angle) of the laser. The horizontal irradiation angle is the irradiation angle with respect to a vertical plane (vertical plane). The encoder may be built into the laser rangefinder or attached externally to the laser rangefinder. Note that in this embodiment, the irradiation angle is not limited to the pitch angle and yaw angle, but may also include the roll angle. The laser rangefinder may also be configured so that the inclinometer detects the vertical irradiation angle and roll angle of the laser. The laser rangefinder may also be configured so that the encoder detects the horizontal irradiation angle and roll angle of the laser. The irradiation angles (pitch angle, yaw angle, and roll angle) can also be determined by measurement using a separate means.

[0018] The control device 3 is a data logger that records the measurement values ​​of the laser rangefinder installed in the measuring device 2. For example, the control device 3 can be connected to the laser rangefinder via a wired connection so that they can communicate with each other, but this is not limited thereto, and for example, the control device 3 can be connected to the processing device 1 so that they can communicate with each other wirelessly. For example, the control device 3 can be connected to the processing device 1 so that they can communicate with each other wirelessly, but this is not limited thereto, and for example, the control device 3 can be connected to the processing device 1 so that they can communicate with each other wirelessly. The wireless connection between the control device 3 and the processing device 1 can be achieved via an access point installed inside the tunnel 4, but this is not limited thereto. The control device 3 can transmit the measurement values ​​obtained from the laser rangefinder to the processing device 1. Furthermore, when an administrator outputs a request from the console, the processing device 1 can transmit a control signal to the control device 3. The control device 3 can control the processing of the laser rangefinder according to the control signal. For example, it can control the adjustment of the exposure time of laser irradiation.

[0019] The control device 3 may have built-in non-volatile memory. The measurement values ​​measured by the laser rangefinder are stored in the memory. Even if the wireless function provided in the tunnel 4 goes down for various reasons (e.g., access point failure), the measurement values ​​stored in the memory will not be erased. Furthermore, if the laser rangefinder and the control device 3 are operating normally, the measurement values ​​can continue to be stored in the memory even when the wireless function is down. After communication is restored, the control device 3 can sequentially output the measurement values ​​stored in the memory. If a wireless function failure or other error occurs, the processing device 1 can notify the administrator of the cause of the error. The error can be, for example, a communication error or a measurement error, but is not limited to these. The error can be notified, for example, by a screen display on a console, an alarm output, or by a notification means installed inside the tunnel 4, but is not limited to these. The control device 3 can also be installed near the wall surface of the tunnel 4. However, the installation position of the control device 3 can be changed as appropriate.

[0020] The processing device 1 includes a measurement unit 11, an angle correction unit 12, a display control unit 13, a database 14, and a setting unit 15. The measurement unit 11 analyzes distance data indicating the distance between the laser rangefinder and the laser irradiation position to measure the amount of displacement inside the tunnel 4. For example, the distance data includes, but is not limited to, the measurement value (distance) of the laser rangefinder, an identifier of the laser rangefinder, information indicating the position of the laser rangefinder, information indicating the attitude (e.g., angle) of the laser rangefinder, an identifier of the cross section 5 including the laser irradiation position, and measurement timing (e.g., timestamp). The angle correction unit 12 performs angle correction of the amount of internal space displacement using the irradiation angle detected by the angle detection unit. For example, if the irradiation angle with respect to the horizontal plane is θ and the measurement value (internal space displacement) of the laser rangefinder is L, the amount of internal space displacement in the vertical direction is L × sin θ, and the amount of internal space displacement in the horizontal direction is L × cos θ. The display control unit 13 controls the display of image data generated by image processing of the processing device 1. The image data can be, for example, but is not limited to, a visualization of the analysis results of the measurement unit 11 in a predetermined display format. In addition, a console communicably connected to the processing device 1 can display the image data on a screen under the control of the display control unit 13. The database 14 stores distance data. The database 14 also stores the analysis results of the measurement unit 11. For example, the analysis results of the measurement unit 11 include, but are not limited to, the amount of internal displacement. The setting unit 15 performs settings related to the laser rangefinder.

[0021] (Single cross section measurement) In the case of Figure 1, for the measuring devices 2 disposed for each cross section 5, the laser range finder mounted on the measuring devices 2 is fixed at a predetermined irradiation angle, and can irradiate a laser at a predetermined circumferential position within the plane of the cross section 5. In Figure 1, the irradiated laser is indicated by a dashed arrow. It is preferable to adjust the irradiation angle of the laser range finder so that the laser irradiation positions are evenly distributed over the entire circumferential direction of the cross section 5.

[0022] The laser rangefinder measures the distance to the irradiation position on the tunnel wall surface of the cross section 5 and records the measured value. The control device 3 acquires and records the measured values ​​from each of the laser rangefinders. When the processing device 1 sends a request to send the measured value to the control device 3 in accordance with the administrator's operation, the control device 3 can send the recorded measured value to the processing device 1. The measurement unit 11 of the processing device 1 can process the measured value from the control device 3 and output distance data indicating the distance between the laser rangefinder and the laser irradiation position. The measurement unit 11 can also analyze the output distance data and measure the amount of internal displacement of the tunnel 4.

[0023] A known method for measuring the amount of internal displacement can be used. Although a detailed description will be omitted, for example, the difference between the initial value of the geometric information of the cross section 5 and the latest value of the geometric information of the cross section 5 can be calculated as the amount of internal displacement of the tunnel 4. Here, the initial value of the geometric information of the cross section 5 can be, for example, the shape of the cross section 5 obtained from distance data output by processing the measurement value at the start of measurement by a laser rangefinder. Furthermore, the latest value of the geometric information of the cross section 5 can be, for example, the shape of the cross section 5 obtained from distance data output by processing the measurement value at the latest measurement by a laser rangefinder.

[0024] As shown in Figure 1, the same processing as above is carried out for each cross section 5 set along the extension direction of the tunnel 4, and the amount of internal displacement of the tunnel 4 can be measured for each cross section 5. As excavation progresses, a new cross section 5 is set on the face side, and the amount of internal displacement of the tunnel 4 can be measured for the set cross section 5.

[0025] The measuring device 2 and the control device 3 can also be installed on the wall of the tunnel 4 at a position away from the cross section 5 to be set in the direction of extension of the tunnel 4. In this case, the laser rangefinder can be irradiated at an angle (yaw angle) toward the cross section 5 where the laser rangefinder is installed, and can be irradiated at a predetermined circumferential position of the target cross section 5. Although the measurement value is an oblique distance, fixed-point observation using the laser rangefinder is possible. The measurement unit 11 of the processing device 1 can process the measurement value from the control device 3 and output distance data indicating the oblique distance between the laser rangefinder and the laser irradiation position. In addition, the measurement unit 11 can analyze the output distance data and measure the amount of internal displacement of the tunnel 4 for the target cross section 5.

[0026] For example, depending on the on-site conditions inside the tunnel 4, it is preferable to dispose the measuring device 2 and the control device 3 at a distance from the target cross section 5. In particular, if an obstacle exists on the target cross section 5, it is preferable to dispose the measuring device 2 and the control device 3 so as to avoid the obstacle. According to this embodiment, the degree of freedom in disposing the measuring device 2 and the control device 3 can be increased.

[0027] (Other measurement methods) There are various ways to measure internal displacement using a laser rangefinder. Figure 2 is an explanatory diagram of multiple cross-section measurement for a shield tunnel. Figure 3 is an explanatory diagram of single cross-section measurement using a divided arrangement for a shield tunnel. Figure 4 is an explanatory diagram of single cross-section measurement for a mountain tunnel.

[0028] As shown in Figure 2, multiple cross sections 5 can be set corresponding to one measuring device 2, enabling multiple cross section measurement. Multiple cross section measurement is a measurement method in which single cross section measurements are performed in parallel on multiple cross sections 5 using one measuring device 2. In other words, multiple cross section measurement is a measurement method in which multiple horizontal irradiation angles (yaw angles) are prepared as the irradiation angle of the laser emitted by the laser range finder. Each of the laser range finders mounted on the measuring device 2 irradiates a predetermined circumferential position on one of the multiple cross sections 5 to be measured.

[0029] The laser rangefinder mounted on the measuring device 2 is fixed at a predetermined irradiation angle, and can irradiate a laser beam at a predetermined circumferential position of one of the multiple cross sections 5. In Figure 2, the irradiated laser beam is indicated by a dashed arrow. In particular, the yaw angle of the laser rangefinder can be changed appropriately depending on the cross section 5 to be irradiated, and the laser rangefinder can be fixed.

[0030] As shown in Figure 3, single cross-section measurement can be achieved by a split arrangement. Split arrangement means that multiple measuring devices 2 (two in Figure 3) are arranged for one target cross-section 5. The laser range finders mounted on each measuring device 2 can be handled in the same way as in the case of single cross-section measurement. Note that split arrangement can also be used to achieve multiple cross-section measurement.

[0031] As shown in Fig. 4, single cross-section measurement can be realized not only in shield tunnels but also in mountain tunnels (hereinafter referred to as tunnel 4a). In the case of mountain tunnels, for example, the distance from both ends of the tunnel 4a in the width direction to the top end is measured. According to this embodiment, single cross-section measurement can be performed by disposing measuring devices 2 at both ends of the tunnel 4a in the width direction and preparing laser range finders whose irradiation position is the top end of the cross section 5.

[0032] As with shield tunnels, multiple cross-section measurements can be achieved for mountain tunnels. Also, single-section measurements and multiple-section measurements can be achieved by dividing the installation. For the sake of convenience, when there is no need to distinguish between shield tunnels and mountain tunnels, the explanation will continue by referring to them as tunnel 4.

[0033] (Adjusting exposure time) Laser rangefinders have a mechanism that controls the laser irradiation by opening and closing a shutter provided for the light source. The time that the shutter is open is the exposure time. The measurement accuracy of a laser rangefinder depends on the exposure time. It is preferable to adjust the exposure time depending on the surrounding environment of the laser rangefinder and the measurement distance. Furthermore, the longer the exposure time, the greater the amount of reflected light and the better the measurement accuracy, but there is also the disadvantage that the measurement value will contain more noise.

[0034] In this embodiment, for example, the exposure time of the laser rangefinder can be remotely adjusted by sending a control signal from the processing device 1 to the measuring device 2 in response to a request from the console. The measurement accuracy of the laser rangefinder can be optimized depending on the surrounding environment of the laser rangefinder, the measurement distance, etc. The setting unit 15 of the processing device 1 can, for example, set the exposure time in response to a request from the console and output a control signal including the set exposure time. Furthermore, if a request to change the exposure time is received from the console, the setting unit 15 can set the changed exposure time and output a control signal including the set exposure time. The measurement pitch of the laser rangefinder can also be remotely adjusted. The setting unit 15 can set the measurement pitch in response to a request from the console and output a control signal including the set measurement pitch. Furthermore, if a request to change the measurement pitch is received from the console, the setting unit 15 can set the changed measurement pitch and output a control signal including the set measurement pitch.

[0035] (Measurement value filtering) The laser rangefinder may output an extremely short distance measurement value (an abnormal value) due to events such as the laser irradiation being blocked by pedestrians or vehicles moving inside the tunnel 4, or due to dust or dirt floating inside the tunnel. In addition, noise (an abnormal value) may occur due to the exposure time as already explained. It is preferable that the measurement unit 11 has a filtering function for the measurement values ​​obtained from the laser rangefinder. Filtering can eliminate abnormal values, contributing to improving measurement accuracy.

[0036] Furthermore, the measurement unit 11 can analyze the laser reflected from the measurement target. More specifically, the measurement unit 11 can analyze the wavelength, waveform, etc. contained in the laser reflected from the irradiation position on the wall surface of the tunnel 4. The measurement unit 11 can output the measurement quality (SQ: Signal Quality) as the analysis result. The measurement quality is an index that quantifies the reliability of the measurement value measured by the laser rangefinder. The larger the value, the higher the measurement quality. The measurement unit 11 can use the measurement quality to perform a filtering process on the measurement values ​​acquired from the laser rangefinder. For example, the measurement unit 11 can exclude measurement values ​​whose measurement quality is below a predetermined threshold. This can improve the measurement accuracy.

[0037] (Statistical processing) The measurement unit 11 can perform statistical processing on the measurement values ​​acquired from the laser rangefinder. For example, the measurement unit 11 can perform statistical processing on the acquired measurement values ​​using standard deviation. In other words, the measurement unit 11 can calculate the standard deviation of the acquired measurement values ​​and exclude measurement values ​​that deviate from the standard deviation.

[0038] Furthermore, the measurement unit 11 can calculate a moving average value over time for the acquired measurement values. The measurement values ​​are values ​​obtained at predetermined times and can be arranged in chronological order. The measurement unit 11 can set any interval over time and calculate the average value of the measurement values ​​belonging to the set interval. Furthermore, the start time and end time of the interval can be changed as appropriate for calculation. Therefore, the measurement unit 11 can output a stable calculated value.

[0039] (Angle correction) The amount of internal displacement of the tunnel 4 measured by the measurement unit 11 is a three-dimensional vector. For example, the measurement unit 11 can use the irradiation angle of the laser rangefinder to decompose the amount of internal displacement into a horizontal component, a vertical component, and a component in the extension direction of the tunnel 4. If the irradiation direction of the laser from the laser rangefinder is parallel to the cross section 5, the component of the internal displacement in the extension direction of the tunnel 4 can be set to zero. Depending on the shape of the tunnel 4, it may be preferable to determine the component of the internal displacement in an arbitrary direction. The measurement unit 11 can determine the component of the internal displacement in an arbitrary direction by performing a weighting calculation using the irradiation angle of the laser rangefinder for each of the horizontal component, vertical component, and component in the extension direction of the tunnel 4.

[0040] As mentioned above, the measuring device 2 and the control device 3 may be placed away from the target cross section 5 to avoid obstacles, etc. In this case, the angle correction unit 12 can perform angle correction of the amount of internal displacement. The laser rangefinder, which is originally placed at a predetermined irradiation angle, will irradiate the target cross section 5 at an angle (not parallel to the tunnel width direction). For this reason, the measured distance will be increased compared to when the laser rangefinder is irradiated on a cross section that crosses the laser rangefinder (not necessarily the cross section set as the measurement target). The amount of increase in distance depends on the distance between the laser rangefinder and the target cross section 5.

[0041] Therefore, for a laser rangefinder with a set irradiation angle, the virtual position of the laser rangefinder, which will cross the cross section 5 of the target by temporarily moving it by the separation distance, is geometrically calculated, and the virtual distance is calculated between the irradiation position on the cross section 5 of the target by the laser rangefinder at that virtual position. Furthermore, using the separation distance and the virtual distance, the angle (hereinafter referred to as the composite angle) between the cross section crossing the laser rangefinder (at its original position) and the irradiation direction of the laser from the laser rangefinder is geometrically calculated. Furthermore, the composite angle can be used to calculate the above-mentioned distance increase. The angle correction unit 12 can correct the amount of internal displacement taking into account the distance increase. In other words, the angle correction unit 12 can correct the amount of internal displacement using the irradiation angle set in the laser rangefinder.

[0042] The angle correction by the angle correction unit 12 can also be applied to multiple cross-section measurement (FIG. 2). That is, among the multiple cross-sections 5, the angle correction by the angle correction unit 12 can be applied to the cross-section 5 that is obliquely illuminated by the laser rangefinder. The irradiation angle set in the laser rangefinder may be the value of the inclinometer attached to the laser rangefinder. Alternatively, the irradiation angle may be an angle calculated by referring to the CAD data of the tunnel 4. When using an inclinometer, one inclinometer is sufficient for single cross-section measurement, but for multiple cross-section measurement, it is advisable to increase the number of inclinometers according to the number of target cross-sections 5.

[0043] (Monitoring of internal displacement) The display control unit 13 can generate image data that visualizes in a predetermined display format the amount of internal displacement measured by the measurement unit 11. A console that is communicably connected to the processing device 1 can display the amount of internal displacement on a screen, allowing the user of the console to monitor the amount of internal displacement.

[0044] There are various display formats. For example, it is possible to prepare a screen display of the amount of internal displacement for shield tunnel specifications and a screen display of the amount of internal displacement for mountain tunnel specifications. This is in consideration of the fact that the number of measurements required differs between shield tunnels and mountain tunnels. The measurement value (distance) of the laser rangefinder and the measurement value of the amount of internal displacement by the measurement unit 11 may be displayed as the measurement value of the latest measurement by the laser rangefinder. It is also possible to display the history of measurement values ​​from the start of measurement by the laser rangefinder to the latest measurement. The measurement values ​​may be displayed numerically or as a graph. The change in the amount of internal displacement over time may be displayed in the specified unit of the laser rangefinder or in the unit of the cross section 5.

[0045] Fig. 7 shows the main screen for monitoring the amount of internal displacement for mountain tunnels. The display control unit 13 can control the display of the main screen in Fig. 7 and can display it on a console that is communicatively connected to the processing device 1. For example, the display control unit 13 can display a list that associates "TD" (tunnel direction), "jig No.", "distance meter," "difference from initial value," and a graph of the change in the amount of internal displacement over time.

[0046] "TD" indicates the distance [m] traveled into the mountain tunnel from the entrance. "Jig No." indicates the identifier of the jig that fixes the laser rangefinder. "Range meter" indicates the identifier (A, B, C, D) of the laser rangefinder. The laser irradiation direction of the laser rangefinder (A, B, C, D) for each TD is as shown in the illustration on the right side of Figure 7. The "difference from the initial value" indicates the difference between the measurement value by the measurement unit 11 and the initial value at the start of measurement (the distance between a specific laser rangefinder and the irradiation position). The difference is expressed in the following formats: "X" (difference in the tunnel extension direction [mm]), "Y" (difference in the tunnel width direction [mm]), "Z" (difference in the tunnel vertical direction [mm]), "θ A ” (the angle between the lasers emitted from the laser distance meters (A, C)), “θ B " (the angle formed by the lasers emitted from the laser range finders (B, C)), but the expression format is not limited to this. The graph of the change in internal displacement over time is a graph with the vertical axis representing the displacement [mm] from the initial value and the horizontal axis representing time. The displacement from the initial value on the vertical axis is a value calculated using a predetermined formula using various values ​​of the "difference from the initial value." The time on the horizontal axis can indicate the time period of the excavation work.

[0047] According to the graph of change over time in Figure 7, it is possible to predict whether the amount of internal displacement has reached the primary control value or the secondary control value. Here, the primary control value is a threshold (absolute value) for the amount of internal displacement, and if the amount of internal displacement exceeds the primary control value, it is preferable to take passive measures such as strengthening monitoring for excavation work. Furthermore, the secondary control value is a threshold (absolute value) for the amount of internal displacement that is greater than the primary control value. If the amount of internal displacement exceeds the secondary control value, it is necessary to take active measures such as reinforcement work for excavation work. Note that the values ​​and meanings of the primary and secondary control values ​​are not limited to these and can be changed as appropriate.

[0048] Fig. 8 shows the main screen for monitoring the amount of internal displacement of a shield tunnel. The display control unit 13 can control the display of the main screen in Fig. 8 and can display it on a console connected to the processing device 1 so that it can communicate with the processing device 1. For example, the display control unit 13 can display a list that associates "Check for changes over time," "Jig No.," "Equipment installation R number," "Distance meter No.," "Difference from initial value [mm]," and "Management."

[0049] "Check change over time" is a check box field for displaying a graph of the change over time in the amount of inner space displacement for the target ring (R). "Jig No." indicates the identifier of the jig that fixes the laser rangefinder. The "equipment installation R number" indicates the identifier of the ring (R) used in the shield tunnel. The equipment installation R number can indicate the distance [m] traveled from the entrance of the mountain tunnel into the tunnel (the larger the R number, the greater the distance [m]). "Range meter No." indicates the identifier (A, B, C, D) of the laser rangefinder. The direction of laser irradiation by the laser rangefinder (A, B, C, D) for each ring (R) is as shown in the illustration on the right side of Figure 8. The "difference from the initial value [mm]" indicates the difference between the measurement value by the measurement unit 11 and the initial value at the start of measurement (the distance between the specific laser rangefinder and the irradiation position). The difference can be expressed as the amount of displacement [mm] from the initial value, but the expression format is not limited to this. "Management" indicates the evaluation result of the value of "difference from initial value [mm]." For example, if the value of "difference from initial value [mm]" of the target ring (R) exceeds the primary management value, "●" is registered in the "Management" column. Note that the conditions for registration in the "Management" column are not limited to this.

[0050] FIG. 9 is an example of a graph showing the change over time of the amount of internal displacement. For example, suppose a console user checks the "Check change over time" checkbox for a ring (R) that has a "●" registered in the "Management" column, and clicks the "Display graph over time" button on the right side of FIG. 8. In this case, the display control unit 13 can control the display of the change over time of the amount of internal displacement measured by the measurement unit 11, and can create the graph of change over time shown in FIG. 9 for the target ring (R). The content of the graph of change over time in FIG. 9 is substantially the same as the content of the graph of change over time in FIG. 7.

[0051] [jig] The following describes a jig for fixing the laser rangefinder to the wall surface of the tunnel 4. Fig. 5 is an overall perspective view of the jig. In Fig. 5, up and down are approximately vertical directions, left and right are approximately the extension direction of the tunnel 4, and front and back are approximately the width direction of the tunnel 4.

[0052] As shown in FIG. 5, the jig 6 includes two base members 61, two first support members 62, and four second support members 63. The basic members 61 are square timbers with a rectangular cross section (square pipes in this embodiment). When the jig 6 is attached to the wall surface of the tunnel 4, the two basic members 61 extend substantially vertically and are arranged side by side with a gap between them. The first support members 62 are plates with an L-shaped cross section. The first support members 62 extend substantially to the left and right, and are fixed to the upper and lower parts of the front surfaces of the base members 61, 61, respectively. The second support members 63 are plate materials with an L-shaped cross section. Each second support member 63 extends approximately in the front-to-rear direction and is connected to the upper and lower sides of the base member 61 and to the bottom surface of the first support member 62. The second support members 63 protrude laterally from the first support member 62 in a cantilevered manner.

[0053] A pedestal portion 64 can be attached to each end of the first support member 62. The pedestal portion 64 is rectangular. The pedestal portion 64 can be fixed to the first support member 62 with bolts or the like. Furthermore, a pan head 65 can be placed on each of the pedestal portions 64. The pan head 65 is a member to which the laser rangefinder 7 can be attached. The pan head 65 can be fixed to the pedestal portions 64. Therefore, the laser rangefinder 7 can be fixed to the jig 6.

[0054] Furthermore, the pan head 65 has a mechanism that can adjust the attitude of the laser rangefinder 7. Therefore, the laser rangefinder 7 is fixed to the jig 6 so that the attitude thereof can be freely adjusted. As shown in Fig. 5, the jig 6 can accommodate a total of four laser rangefinders 7, with the first support member 62 as a base.

[0055] A total of four vibration-isolating rubbers 66 (vibration-isolating parts) can be attached to the rear end surface of the upright plate of the first support member 62. The vibration-isolating rubbers 66 are parts that come into close contact with the wall surface of the tunnel 4, and absorb vibrations transmitted from the wall surface of the tunnel 4 to the jig 6. The vibration-isolating rubbers 66 can eliminate vibrations transmitted to the laser rangefinder 7, preventing positional and posture shifts (movements) of the laser rangefinder 7.

[0056] For example, a through hole (not shown) is provided at the end of the upright plate of the first support member 62. Furthermore, a screw hole (not shown) is provided in the vibration-proof rubber 66, extending from one surface of the vibration-proof rubber 66 to the inside, and a bolt 67 is screwed into the screw hole. The through hole in the base portion 64 communicates with the through hole in the first support member 62. The bolt 67 is threadably inserted and fastened from the rear of the upright plate of the first support member 62 through the through hole in the first support member 62 and the through hole in the base portion 64. With such a mechanism, the vibration-proof rubber 66 can be attached to the jig 6.

[0057] More specifically, the vibration-proof rubber 66 is connected to the first support member 62 and the pedestal 64 by bolts 67. The laser rangefinder 7 and the camera platform 65 are fixed to the pedestal 64. In other words, the jig 6 can have a structure in which each laser rangefinder 7 is connected to each vibration-proof rubber 66. This allows a mechanism to support the jig 6 using each of the bolts 8 and the vibration-proof rubber 66 (described later), thereby maximizing the vibration-proof performance of the jig 6. Note that, for example, a predetermined connecting mechanism (not shown) may be introduced into the laser rangefinder 7, so that each laser rangefinder 7 is directly connected to each vibration-proof rubber 66. In other words, a structure may be used in which the base 64 or the upright plate of the first support member 62 is not interposed.

[0058] By rotating the vibration-isolating rubber 66 around the axis of the bolt, the distance from the rear surface of the end of the standing plate of the first support member 62 to the rear surface of the vibration-isolating rubber 66 (the surface that abuts against the wall surface of the tunnel 4) can be adjusted. In other words, by moving the vibration-isolating rubber 66 back and forth, the position of the jig 6 can be adjusted. In addition, a nut (not shown) may be welded to the rear end surface of the upright plate of the first support member 62, a hole may be drilled in the nut, and the through hole of the first support member 62, the hole of the nut, and the through hole of the base portion 64 may be connected, and a bolt may be fastened so as to pass through the through hole of the first support member 62, the hole of the nut, and the through hole of the base portion 64.

[0059] (action) The procedure for installing the laser distance meter is as follows. An insert nut (not shown) into which the bolt 8 can be threaded is embedded in the wall of the tunnel 4 at the location where the jig 6 is to be attached. If there is no insert nut or the surface is one to which it cannot be attached (for example, a steel segment), a magnet may be used instead of the bolt 8 for attachment.

[0060] First, the jig 6, with the first support member 62 and second support member 63 assembled to the basic member 61, is placed against the wall of the tunnel 4. At this time, the gap between the two basic members 61 is connected to the insert nut (threaded hole) on the wall of the tunnel 4. Next, the bolt 8 is inserted from the front of the basic member 61 into the gap between the two basic members 61 and threadedly inserted into the insert nut (threaded hole) on the wall of the tunnel 4. As a result, the hexagonal nut 81 threadedly inserted onto the bolt 8 abuts against the front of the basic member 61. Next, with the bolt 8 inserted, the jig 6 is moved up and down to determine the height of the jig 6, and then the bolt 8 is tightened. Tightening the bolt 8 presses the jig 6 against the wall of the tunnel 4, causing the vibration-damping rubber 66 to come into close contact with the wall of the tunnel 4. As a result, the jig 6 is fixed to the wall of the tunnel 4. The posture of the entire jig 6 can be adjusted by rotating the vibration-proof rubber 66 and moving it back and forth relative to the rear surface of the end of the standing plate of the first support member 62.

[0061] Thereafter, the pan head 65 is placed and attached to the pedestal 64 at each end of the first support member 6. Next, the attitude of the laser rangefinder 7 attached to the pan head 65 is adjusted appropriately. By following the above procedure, the laser rangefinder 7 in the desired attitude can be placed in the jig 6. In the case of a mountain tunnel, for example, by installing one anchor bolt on the sprayed surface, the jig 6 can be attached to the tunnel wall surface using the same procedure as above.

[0062] (Used in conjunction with TS (total station)) The internal displacement measurement system 100 of this embodiment may be equipped with a TS. The TS can be disposed at an appropriate location inside the tunnel 4. For example, as shown in FIG. 5, a mirror target 91 (target) can be fixed to the jig 6. Also, a target seal 92 (target) may be affixed to the second support member 63, which is an example of a component of the jig 6, or to the laser rangefinder 7. By aiming the TS at the mirror target 91 and the target seal 92, the coordinates of the mirror target 91 and the target seal 92 can be given.

[0063] The relative positional relationship (offset) between the mirror target 91 and the target seal 92 and each of the laser rangefinders 7 fixed to the jig 6 can be known in advance by a well-known method. Therefore, coordinates can be given to each of the laser rangefinders 7 by the TS. Furthermore, the relative positional relationship (offset) between each of the laser rangefinders 7 and the circumferential position of the cross section 5, which is the laser irradiation position, can be known in advance by measurement by the laser rangefinder 7. Therefore, coordinates can be given to each of the laser irradiation positions by the TS.

[0064] The control device 3 is communicatively connected to the TS. Therefore, the processing device 1 is communicatively connected to the TS via the control device 3. The processing device 1 may also be communicatively connected to the TS and exchange information with the TS. For example, the TS can repeatedly measure the coordinates of the mirror target 91 and the coordinates of the target sticker 92 at a predetermined timing. The processing device 1 can acquire the measurement results from the TS and measure the changes over time in the coordinates of the mirror target 91 and the coordinates of the target sticker 92. By analyzing these changes over time, the processing device 1 can determine the positional deviation of the jig 6 and the positional deviation of the laser rangefinder 7 (determination of movement). The measurement unit 11 can measure the amount of displacement inside the tunnel 4 by taking into account the determination results of the positional deviation of the jig and the determination results of the laser rangefinder 7.

[0065] [process] The processing of the method for measuring displacement in the interior space of this embodiment will now be described. Fig. 6 is a flowchart showing the processing of the method for measuring displacement in the interior space of this embodiment. The laser rangefinder 7 irradiates the cross section 5 of the tunnel with a laser and repeatedly measures the distance to the irradiated position at a predetermined timing.

[0066] First, the processing device 1 acquires the measurement value of the laser rangefinder 7 via the control device 3 (step S1). The processing device 1 generates distance data for the acquired measurement value and stores it in the database 14. Next, the measurement unit 11 of the processing device 1 analyzes the distance data and measures the amount of internal displacement of the tunnel 4 (step S2). When measuring the amount of internal displacement, the measurement unit 11 may perform angle correction using the angle correction unit 12. Furthermore, when measuring the amount of internal displacement, the measurement unit 11 can also take into account the results of determining the positional deviation of the jig 6 and the laser rangefinder 7 based on the measurement results of the TS. Finally, the display control unit 13 of the processing device 1 performs display processing for the amount of internal displacement measured by the measurement unit 11 (step S3). A console communicatively connected to the processing device 1 can display the amount of internal displacement in a predetermined display format in accordance with the display control unit 13. This completes the process of the method for measuring displacement in the interior space.

[0067] [effect] According to this embodiment, the measurement accuracy of the displacement inside the tunnel can be improved. More specifically, fixed-point observation can be achieved at the corresponding irradiation position by laser irradiation without rotating each of the multiple laser rangefinders as in the past. Therefore, once the irradiation position is set, it will not shift due to the operation of the laser rangefinder, and the measurement accuracy of the tunnel displacement can be improved.

[0068] Furthermore, by providing the angle correction unit 12, even if the posture of the laser rangefinder 7 arranged on the jig 6 is changed as needed due to the presence of an obstacle or the like, the amount of internal displacement at the corresponding irradiation position can be accurately measured. Furthermore, by providing the setting unit 15, it is possible to set or change the exposure time, measurement pitch, etc. for the laser rangefinder 7. Furthermore, by providing the display control unit 13, it is possible to visually grasp the change over time of the amount of internal air displacement. Therefore, it is possible to display the change over time of the amount of internal air displacement when using a laser rangefinder with changed settings, and it is possible to optimize the settings of the laser rangefinder based on the change over time of the amount of internal air displacement. Furthermore, by providing the jig 6 with the vibration-isolating rubber 66, the vibration-isolating performance of the jig 6 can be maximized. Furthermore, by performing filtering processing using the measurement quality, it is possible to exclude measurement values ​​whose measurement quality is below a predetermined threshold, thereby improving measurement accuracy. Furthermore, by providing a TS, it is possible to improve the measurement accuracy of the tunnel interior displacement by using the coordinates of the laser rangefinder 7 and the coordinates of the irradiation position. Also, by observing the change in coordinates over time, it is possible to monitor whether or not there is any positional deviation of the jig or laser rangefinder.

[0069] [others] (a): This is a method of measuring distance using a laser rangefinder 7, but it does not have to be a measurement targeting a cross section 5, such as a single cross section measurement or multiple cross section measurement. For example, it may be a method of measuring the distance when one laser rangefinder 7 irradiates a laser at an arbitrary irradiation position on the wall of the tunnel 4 (single point measurement). It may also be a method of preparing multiple laser rangefinders 7 that irradiate a laser at an arbitrary irradiation position on the wall of the tunnel 4, and measuring multiple types of distances (multiple point measurement). (b): In the jig 6, only one basic member 61 may be prepared, or three or more may be prepared. The second support members 63 may be arranged side by side depending on the number of basic members 61. Therefore, the number of laser rangefinders 7 arranged side by side in front of the second support members 63 can be changed as appropriate. Also, only one first support member 62 may be prepared, or three or more may be prepared. Three or more first support members 62 can be attached to the basic member 61 and arranged side by side vertically. Therefore, the number of laser rangefinders 7 arranged side by side in front of the second support members 63 can be changed as appropriate.

[0070] (c) It is also possible to realize a technology that appropriately combines the various technologies described in this embodiment. (d) The software described in this embodiment can be realized as hardware, and vice versa. (e) In addition, the components of the present invention can be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0071] 100 Inner space displacement measurement system 1 Processing equipment 2 Measuring equipment 3. Control equipment 4,4a Tunnel 5 Cross Section 6 Jig 7 Laser rangefinder 8 volts 11 Measurement section 12 Angle correction unit 13 Display control unit 14 Database 15 Setting section 61 Basic components 62 first support member 63 Second support member 64 Mating concave plate 65 Base 66 Anti-vibration rubber 67 volts 81 Hexagon nut 91 Mirror Target (Target) 92 Target Seal (Target)

Claims

1. a plurality of laser range finders that are disposed on a jig fixed to a wall surface of the tunnel and that irradiate the wall surface of the tunnel with a laser; An internal displacement measurement system comprising: a processing device having a measurement unit that analyzes distance data indicating the distance between the laser rangefinder and the laser irradiation position to measure the internal displacement of the tunnel.

2. the laser rangefinder includes an angle detection unit that detects an irradiation angle of the laser rangefinder; 2. The internal space displacement measuring system according to claim 1, wherein the processing device includes an angle correction unit that performs angle correction of the internal space displacement amount using the irradiation angle detected by the angle detection unit.

3. The internal displacement measurement system according to claim 2, wherein a plurality of cross-section measurements are performed using a plurality of horizontal irradiation angles prepared as the irradiation angle.

4. The processing device includes: a setting unit for setting the laser rangefinder; The internal displacement measuring system according to claim 1 , further comprising a display control unit that controls the display of the change over time in the internal displacement amount measured by the measurement unit.

5. The jig includes a vibration-isolating part that is in close contact with the wall surface of the tunnel, 2. The system for measuring displacement in an internal space according to claim 1, wherein the laser range finder is connected to the vibration isolation unit.

6. The internal displacement measurement system of claim 1, wherein the measurement unit analyzes the laser reflected from the irradiation position, outputs measurement quality as the analysis result, and performs filtering processing on the measurement values ​​obtained from the laser rangefinder using the output measurement quality.

7. one or more targets attached to the jig; and a total station disposed within the tunnel, 7. The system for measuring displacement in an internal space according to claim 1, wherein the target is used to provide coordinates for each of the laser range finders and the irradiation position.

8. a step in which a plurality of laser range finders, which are arranged on a jig fixed to a wall surface of the tunnel, irradiate the wall surface of the tunnel with lasers; an internal displacement measurement method comprising a step in which a measurement unit of a processing device analyzes distance data indicating the distance between the laser rangefinder and the laser irradiation position, and measures the internal displacement of the tunnel.

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