Shield prefabricated part assembling measurement device and installation method

Abstract

This application discloses a shield precast component assembly measurement device and installation method. The device and corresponding control terminal enable real-time data acquisition and calculation, solving the problems of high assembly accuracy and low efficiency caused by human factors in existing technologies. The measurement device includes a protective shell, a distance measurement module, and an inclination measurement module. The measurement method includes the following steps: (1) installation of the measurement device; (2) zero-point measurement; (3) establishment of an independent coordinate system for the precast component; (4) zero-point data calculation; (5) precast component assembly; (6) measurement point calculation; (7) four-point fitting of a plane circle; (8) comparison of the circle center coordinates. It has advantages such as high accuracy and efficiency, labor saving, and verifiable process data.

Description

Technical Field

[0001] This application relates to the field of shield tunneling technology, specifically to a shield prefabricated component assembly and measurement device and installation method. Background Technology

[0002] With the development of shield tunneling technology, in order to ensure the construction period, most shield tunnel projects currently adopt synchronous construction for internal structure construction, that is, the internal structure construction is carried out at the same time as shield tunneling. However, due to the slow speed of cast-in-place construction of internal structure and the limited space inside the tunnel, it will lead to inconvenience in the organization of internal structure construction, and will also affect the normal tunneling of shield, thus affecting the construction period of the entire tunnel project.

[0003] To address the problems caused by cast-in-place construction, precast structures can be used, such as arched inverted arch components, U-shaped components, and box culverts—precast concrete components with fixed geometric dimensions. Because they are manufactured through mechanized design and construction, they feature high standardization and precision, ensuring structural quality. Assembly and installation significantly increase construction speed compared to cast-in-place construction. During assembly, the measurement of the precast component's position is crucial; complete and reliable measurements are essential to guarantee the accuracy of installation and project quality. Current measurement methods typically involve surveyors measuring the cross-section at the pre-assembly point, calculating the actual tunnel centerline and elevation, and laying out the precast component assembly lines. The accuracy of this layout and assembly is entirely dependent on the surveyor's skill, making precise control difficult. Furthermore, the measurement and calculation processes are time-consuming and cannot provide real-time data during assembly, impacting the construction progress.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the background technology of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] In view of at least one of the above technical problems, this disclosure provides a shield precast component assembly measurement device and installation method, which completes real-time data acquisition and calculation through the measurement device and corresponding control terminal, solving the problem that the assembly accuracy of the prior art is greatly affected by human factors and has low efficiency.

[0006] According to one aspect of this disclosure, a shield prefabricated component assembly and measurement device is provided, comprising a protective shell, a distance measurement module and an inclination measurement module respectively disposed in the protective shell; the distance measurement module includes two rangefinders forming an angle with each other; the inclination measurement module includes an inclination meter.

[0007] In some embodiments of this disclosure, the rangefinder is a laser rangefinder, and the protective housing has an exit window at the corresponding position.

[0008] According to another aspect of this disclosure, a method for installing precast shield components in a tunnel is provided, implemented based on the aforementioned precast shield component assembly and measurement device, comprising the following steps:

[0009] (1) Installation of measuring devices: Install a measuring device on each of the beam arms on both sides of the corresponding assembly machine, and ensure that the laser beam in each measuring device can irradiate the tunnel wall, and connect the measuring device to the control terminal via wired / wireless connection.

[0010] (2) Zero-position measurement: The assembly machine lifts the precast component to be installed and turns on the measuring device. A total station is used to measure the coordinates of the left and right corners of the front end of the precast component in the geodetic coordinate system, the coordinates of any two points on each laser measuring line of the rangefinder and the corresponding rangefinder readings, the height H of the precast component, the inner radius R of the pipe wall, and the zero-position inclinometer reading γ0.

[0011] (3) Take the midpoint of the line connecting the left and right corners of the front end of the precast component as the origin of the coordinate system and the line connecting the corners as a coordinate axis to establish an independent coordinate system for the precast component. Transform the coordinates of each point obtained in step (2) to the independent coordinate system of the precast component through the transformation parameters of the two coordinate systems, and calculate the slope angle δ between the left and right corners.

[0012] (4) Zero-point data calculation: Under the independent coordinate system of the precast component, the azimuth angles θ1, θ2, θ3, and θ4 of each measuring line are calculated by inverse coordinate calculation, and the zero-point coordinates (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) and zero-point roll angle of each rangefinder are calculated by forward coordinate calculation. ;

[0013] (5) Precast component splicing: The precast component is hoisted to the splicing position by the assembly machine;

[0014] (6) Measurement point calculation: Based on the zero-position data and the real-time distance data S1, S2, S3, and S4 of each rangefinder, calculate the coordinates of each measurement point on the pipe wall illuminated by the laser beam in the independent coordinate system of the precast component. Calculate the roll angle β = γ + γ based on the real-time data γ from the inclinometer. ;

[0015] (7) Fit a plane circle at four points. Fit the center coordinates (X0, Y0) of a plane circle passing through each measuring point in the independent coordinate system of the preform.

[0016] (8) Comparison of center coordinates: Compare the center coordinates of the fitted circle with the center coordinates of the circle corresponding to the proposed installation position, and provide feedback on the position difference information. The assembly machine is then used to adjust the posture of the prefabricated component until the two centers coincide.

[0017] In some embodiments of this disclosure, in step (1), either of the two measuring devices is provided with only a distance measuring module.

[0018] In some embodiments of this disclosure, in step (2), any two points on the laser measuring line are non-coincident and have a certain distance between them.

[0019] In some embodiments of this disclosure, in step (4), the zero rolling angle β0 = slope angle δ - zero tilt meter reading γ0.

[0020] In some embodiments of this disclosure, in step (5), except for the first prefabricated piece, the rear ends of the remaining prefabricated pieces are brought close to the prefabricated pieces that have been installed.

[0021] In some embodiments of this disclosure, in step (6), the coordinates of each measuring point are ( The independent coordinate system of the precast component is the one that is viewed directly from the precast component. The line connecting its left and right corners points to the right is the positive direction of the Y-axis, and the line passing through the origin and going upwards is the positive direction of the X-axis.

[0022] In some embodiments of this disclosure, in step (8), the center coordinates of the circle corresponding to the proposed installation location are (RH, 0).

[0023] In some embodiments of this disclosure, in step (8), the position difference information includes a left-right movement value L. LR =(Y0×cosβ+X0×sinβ), shift value L UD = (X0×cosβ+Y0×sinβ)-(RH).

[0024] One or more technical solutions provided in the embodiments of this application have at least one of the following technical effects or advantages:

[0025] 1. By using a laser rangefinder and inclinometer, real-time acquisition, processing and storage of data during the attitude adjustment of precast components are realized. This effectively solves the technical problem of low efficiency caused by manual measurement and layout in the existing technology, thereby greatly improving measurement efficiency and construction accuracy, and making construction data recordable.

[0026] 2. By acquiring and converting zero-point data, the coordinate information of each distance measuring instrument in an independent coordinate system is obtained. Only the total station needs to be used for measurement during the initial installation and debugging. Subsequent prefabricated components can be directly positioned based on the feedback from the measuring device, avoiding repeated measurements during the installation of each prefabricated component and further improving construction efficiency.

[0027] 3. By introducing the zero roll angle and taking initial error into account, the measurement accuracy can be improved, ensuring the reliability of the measurement and the precision of the prefabricated component installation. Attached Figure Description

[0028] Figure 1 This is a schematic diagram showing the installation position of the shield prefabrication component assembly and measurement device in one embodiment of this application.

[0029] Figure 2 This is a schematic diagram of zero-point data measurement in one embodiment of this application.

[0030] Figure 3 This is a schematic diagram of the azimuth angle of the zero-position data in an embodiment of this application.

[0031] Figure 4 This is a schematic diagram illustrating the calculation of the azimuth angle of the rangefinder from the coordinates of the measuring point in one embodiment of this application.

[0032] Figure 5 This is a schematic diagram illustrating the calculation of the zero coordinates of the laser rangefinder's emission point in one embodiment of this application.

[0033] Figure 6 This is a schematic diagram of a measurement point calculation in one embodiment of this application.

[0034] Figure 7 This is a schematic diagram of the center of a four-point fitted circle in one embodiment of this application.

[0035] Figure 8 This is a schematic diagram of the center of the fitted circle after the prefabricated part is correctly positioned in one embodiment of this application.

[0036] In the above figures, 1 is the tunnel wall, 2 is the U-shaped precast component, 21 is the installed precast component, 22 is the precast component to be installed, 3 is the assembly machine, 4 is the measuring device, 41 is the laser rangefinder, 42 is the inclinometer, A is the observation point on the left side of the precast component, and B is the observation point on the right side of the precast component. Detailed Implementation

[0037] In the description of this application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "vertical," "horizontal," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "connection" and "linkage" in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0038] The programs involved or relied upon in the following embodiments are all conventional or simple programs in this technical field. Those skilled in the art can make conventional choices or adaptive adjustments according to specific application scenarios.

[0039] Unless otherwise specified, all unit modules and other devices involved in the following embodiments are conventional commercially available products.

[0040] To better understand the technical solution of this application, the above technical solution will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] This example discloses a shield prefabricated component assembly and measurement device, including a protective shell, a distance measurement module, and an inclination measurement module.

[0042] The protective shell serves two purposes: firstly, it provides dust and water protection; secondly, it incorporates internal grooves for securing the distance and tilt measurement modules, ensuring they are positioned correctly for measurement. The distance measurement module includes two laser rangefinders positioned at an angle to each other, and the tilt measurement module includes an inclinometer. In this embodiment, the protective shell is a cuboid structure. For ease of measurement and calculation, one laser rangefinder is vertically positioned downwards along the shell's side wall, while the other is positioned at a 45-degree angle to it. Exit windows are provided at corresponding positions on the protective shell and the laser rangefinders' emission ends to ensure unobstructed laser beam emission. Furthermore, the inclinometer is positioned parallel to the top surface of the protective shell for measuring tilt angles.

[0043] This example also discloses a method for installing precast shield components inside a tunnel. The precast components to be installed are U-shaped precast components, which include the following steps:

[0044] (1) Installation of measuring devices: Install a measuring device on each of the two beam arms of the assembly machine, and ensure that the laser beam in each measuring device can irradiate the tunnel wall.

[0045] To achieve real-time monitoring and feedback of the precast component's attitude, see [link / reference]. Figure 1 One of the aforementioned measuring devices needs to be installed on each of the two beam arms of the assembly machine. Since the measuring objects of both measuring devices are the same U-shaped precast component, only one measuring device needs to be equipped with an inclinometer, eliminating the need for an inclinometer in the other measuring device. This ensures reliable measurement while avoiding increased construction costs due to the addition of additional instruments. Furthermore, to ensure the normal operation and measurement reliability of the rangefinder, it is necessary to ensure that the laser beam of the measuring device illuminates the tunnel wall without obstruction, avoiding interference from obstacles in subsequent attitude calculations and adaptive adjustments.

[0046] (2) Zero-position measurement: The assembly machine lifts the precast component to be installed and turns on the measuring device. A total station is used to measure the coordinates of the left and right corners of the front end of the precast component in the geodetic coordinate system, the coordinates of any two points on each laser measuring line of the rangefinder and the corresponding rangefinder readings, the height H of the precast component, the inner radius R of the pipe wall, and the zero-position inclinometer reading γ0.

[0047] To ensure the precast component is correctly positioned at its intended location, its attitude needs to be continuously adjusted using measuring devices. When the precast component is correctly positioned, there is a definite positional relationship between the center of the tunnel wall and the precast component. Therefore, by projecting laser rangefinders from both sides onto various measuring points on the tunnel wall, a fitted circle is created that passes through the bottom edge of the precast component during the attitude adjustment process. A corresponding coordinate system is established with the precast component as the reference. Under this reference, the center of the fitted circle continuously changes position in this coordinate system during the attitude adjustment process. Since the precast component has a definite position coordinate in this coordinate system when it is correctly placed, the difference between the coordinates of the fitted circle's center and the expected position coordinates when the precast component is correctly placed is compared to guide the precast component to make corresponding attitude adjustments until the two coordinates are consistent, at which point the precast component is placed in place. In addition, to simplify and eliminate tedious and time-consuming measurement operations and avoid increasing manpower and equipment for repeated observation of each measuring point, based on the characteristic that the relative position of the measuring device and the prefabricated component does not change during the attitude adjustment process, the spatial position of each measuring device is first determined, and the coordinates of each measuring point are calculated based on the distance measurement information of the rangefinder, thereby saving manpower for measurement.

[0048] After each measuring device is fixed to one of the side beams of the assembly machine, its position is also fixed. Therefore, the first step is to locate and calculate the position of the measuring devices, i.e., to measure the zero-point data. This data acquisition is mainly achieved using a total station. See also Figure 2 First, measure the height H of the precast component and the inner radius R of the tunnel wall.

[0049] To locate the spatial position of the two measuring devices, and since two points can determine a line segment or straight line, see [reference needed]. Figure 2 The coordinates of any two points on the laser beams emitted by each laser rangefinder in the measuring device are observed. In this embodiment, a steel rod is manually used to block the laser beam at any position. A total station is used to observe the coordinates at the intersection of the steel rod and the laser beam, and the readings of each rangefinder are recorded. This process is repeated to complete the observation of the coordinate positions of any two points on each laser beam and the distance measurement. In other embodiments, other obstructions are used to block the laser beam. This determines the position information of the corresponding observation points in each laser beam, and then obtains the coordinate information of each laser rangefinder. In this case, any two points on the laser beam are non-coincident and maintain a certain distance along the direction of the laser beam.

[0050] Since the total station observation data is coordinate information in the geodetic coordinate system, and this coordinate system cannot be directly used to establish a new independent coordinate system for the precast component for fitting the circle, the coordinates of the left and right corners of the square precast component are measured in order to transform between the two coordinate systems, and the transformation parameters between the two coordinate systems are calculated accordingly.

[0051] In addition, since the inclinometer inside the measuring device cannot be guaranteed to be level with the prefabricated component during installation, there will be a certain installation error, which will cause the actual inclination angle to be inconsistent with the inclinometer reading. Therefore, in order to eliminate the installation error, it is also necessary to read the inclinometer reading γ0 at the initial zero position and compare it with the angle actually observed by the total station to obtain the initial error at the zero position.

[0052] (3) Take the midpoint of the line connecting the left and right corners of the front end of the precast component as the origin of the coordinate system and take the line connecting the corners as a coordinate axis to establish an independent coordinate system for the precast component. Transform each point in step (2) to the independent coordinate system of the precast component through the transformation parameters of the two coordinate systems, and calculate the slope angle δ between the left and right corners.

[0053] Since the two measuring devices are installed on both sides of the assembly machine, and the precast component has a symmetrical structure, an independent coordinate system for the precast component is established with the midpoint of the line connecting the left and right corners of the front end of the precast component as the origin and this line as one coordinate axis. (See also...) Figure 2 In this embodiment, facing the section to be installed, the line connecting the left and right corners of the precast component is taken as the Y-axis, with the rightward direction being positive. The straight line passing through the origin and perpendicular to the Y-axis is taken as the X-axis, with the upward direction being positive. After the independent coordinate system of the precast component is established, since the zero-position data observed by the total station is data under the geodetic coordinate system, it needs to be converted into an independent coordinate system. In step (2), the position coordinates of the two corners of the precast component have been observed. Through spatial three-dimensional coordinate transformation, the transformation parameters between the two coordinate systems can be obtained. Then, the observation points on the laser beam of the laser rangefinder can be transformed to the independent coordinate system of the precast component through the transformation parameters between the two coordinate systems.

[0054] In addition, since the precast components are not necessarily horizontal when they are lifted by the assembly machine, in order to know the degree of inclination of the precast components, the slope angle δ between the left and right corner points is calculated by using the coordinate information of the two corner points observed by the total station, based on the difference in the horizontal direction and the difference in the vertical direction between the two coordinate points. The slope angle δ = vertical height difference / horizontal distance difference is calculated.

[0055] (4) Zero-point data calculation: Under the independent coordinate system of the precast component, the azimuth angles θ1, θ2, θ3, and θ4 of each measuring line are calculated by coordinate inverse calculation, and the zero-point coordinates (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) and zero-point roll angle of each rangefinder are calculated by coordinate forward calculation. .

[0056] After establishing an independent coordinate system for the precast component and transforming each observation point to the independent coordinate system of the precast component using the transformation parameters between the two coordinate systems, the position information of each laser rangefinder, including its coordinates in the independent coordinate system of the precast component, can be calculated based on each transformed observation point.

[0057] Since the measuring device is relatively stationary with respect to the precast component once installed in the precast component's independent coordinate system, their spatial positions remain unchanged. Therefore, the fixed position of the measuring device in the precast component's independent coordinate system can be calculated using the corresponding observation information. Using this as a known reference, the coordinates of each measuring point projected onto the pipe wall can be calculated based on the distance information.

[0058] First, the azimuth angles θ1, θ2, θ3, and θ4 of each survey line need to be calculated. In this embodiment, see [reference needed]. Figure 3 0° is defined as the direction parallel to and in the same direction as the positive X-axis, passing through the laser emission point of the laser rangefinder, and clockwise is defined as the positive direction. In step (3), the coordinates of any two points on each survey line observed by the total station have been converted to the independent coordinate system of the precast component through transformation parameters. Therefore, the azimuth angle of each side survey line can be calculated based on the coordinates. See [reference needed]. Figure 4 Given the coordinates of any two points on the laser measuring line of the laser rangefinder in the independent coordinate system of the prefabricated component, the distance differences ΔX and ΔY between the two points in the X and Y axes can be calculated from these coordinates. Furthermore, trigonometric relationships can be used to obtain... =arctan(ΔX / ΔY), since the sum of the interior angles of a triangle is 180 degrees, then =90°- From this, we can obtain =π+ That is, the azimuth angle of the laser rangefinder's measuring line. Similarly, the azimuth angle data of the other measuring lines can be calculated.

[0059] After calculating the azimuth angles of the measuring lines of each laser rangefinder, the zero-point coordinates (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4) of each laser rangefinder are obtained through coordinate forward calculation based on the distances of the rangefinders from the observation points on the measuring lines recorded in step (2). See also... Figure 5 Given the coordinates (X, Y) of an observation point on the survey line, calculate the coordinates of the laser rangefinder's emission point, i.e., the zero-point coordinates (X1, Y1). Furthermore, the distance S1 between the observation point and the emission point is known through the zero-point data. The direction angle is then used to determine the coordinates. By converting trigonometric functions, the components ΔX1 and ΔY1 of the known observation point and emission point on the X and Y axes can be obtained. Therefore, the zero-point coordinates of the emission point are (X+ΔX1, Y+ΔY1). Similarly, the zero-point coordinates of the emission points of the other laser rangefinders can be obtained. From this, the position information of each laser rangefinder in the independent coordinate system of the prefabricated component can be obtained, and based on this, the coordinate information of the measuring points projected by each laser beam onto the pipe wall can be calculated.

[0060] Furthermore, due to installation errors during the installation of the measuring device, the reading of the inclinometer inside may not match the actual tilt angle of the precast component. To eliminate the error caused by the inclinometer not being installed horizontally, it is necessary to calculate the zero roll angle. =Slope angle δ - zero-position inclinometer reading γ0. The difference between the slope between the two corners of the precast component actually observed by the total station and the inclinometer reading is used as the initial installation error of the inclinometer and is taken into account in the subsequent attitude control process of the precast component.

[0061] (5) Precast component splicing: The assembly machine hoists the precast components to the position to be spliced.

[0062] After the initial zero-position data measurement and calculation of the precast components are completed, the precast components can be lowered and installed. Except for the initial first precast component, when assembling each subsequent precast component, the rear end face of the precast component to be assembled needs to be adjusted to fit with the front end face of the precast component that has been installed along the direction of the tunnel boring machine. Subsequently, based on the measurement data of the measuring device, only the front end face of the precast component needs to be adjusted to the design position to complete the assembly of the precast component.

[0063] (6) Calculation of measuring points: Based on the zero-position data and the real-time distance data S1, S2, S3 and S4 of each rangefinder, calculate the coordinates of each measuring point on the pipe wall irradiated by each laser beam in the independent coordinate system of the precast component. Calculate the rolling angle β=γ+β0 based on the real-time data γ of the inclinometer.

[0064] After the zero-point data measurement and calculation are completed, subsequent data measurements and adjustments to the corresponding attitude of the prefabricated component can be made based on the laser rangefinder and inclinometer in the measuring device.

[0065] Based on the zero-position measurement data, the coordinates of each laser rangefinder's emission point in the independent coordinate system of the precast component and the azimuth angle of the corresponding measurement line can be determined. Furthermore, based on the distance information between the emission point and the measurement point projected onto the pipe wall by the laser beam, obtained in real-time from the laser rangefinder, the position coordinates of each measurement point can be calculated. (See also...) Figure 6 Given the coordinates of the exit point ( and survey line distance And by the azimuth of the survey line It can be determined that the coordinates of measuring point N are ( , Similarly, the coordinates of other measuring points can be obtained as follows: ).

[0066] Furthermore, since the inclinometer has an initial installation error during installation, which persists in the subsequent measurement and adjustment of the precast component's attitude data, it is necessary to eliminate the interference of this error on the installation accuracy. The initial zero-position roll angle has been calculated in step (4). That is, the initial error of the tilt angle is During the precast component attitude measurement process, the inclinometer reading is insufficient to characterize the actual attitude of the precast component. It is necessary to consider the initial zero roll angle. Therefore, the actual roll angle β of the precast component = inclinometer reading γ + zero roll angle .

[0067] (7) Fit a plane circle at four points. Fit the center coordinates (X0, Y0) of the plane circle passing through each measuring point according to the coordinates of each measuring point in the independent coordinate system of the precast part.

[0068] Based on step (6), the coordinate information of the four measuring points in the independent coordinate system of the precast component can be calculated. Since any point on the perpendicular bisector of a line segment is equidistant from both ends of the line segment, the four measuring points are connected in pairs to form the two-end line segments. (See [reference]). Figure 7 And draw perpendicular bisectors for the two line segments. The intersection of the two perpendicular bisectors is the center (X0, Y0) of the fitted circle in the independent coordinate system of the preform.

[0069] (8) Comparison of center of the circle: Compare the center of the fitted circle with the center coordinates of the circle corresponding to the proposed installation position, and provide feedback on the position difference information. Adjust the posture of the precast component by the assembly machine until the two centers of the circle coincide.

[0070] Based on the zero-position measurement data, it can be determined that when the U-shaped precast component is correctly installed at the center of the tunnel bottom, see [reference needed]. Figure 8 The center coordinates of the fitted circles at each measuring point should be (RH, 0) in the independent coordinate system of the precast component. Based on this, compare the center coordinates of the fitted circles during the precast component's attitude adjustment process, and adjust the center of the fitted circles accordingly to the desired position (RH, 0). The left and right movement value L of the precast component... LR = (Y0×cosβ+X0×sinβ), positive values ​​shift to the right, negative values ​​shift to the left; the shift value is L. UD = (X0×cosβ+Y0×sinβ)-(RH), where a positive value moves the component upwards and a negative value moves it downwards. This allows for the adjustment and placement of the precast component's orientation, and the data generated during the orientation adjustment process can be completely recorded for future verification.

[0071] Although some preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0072] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A method of installing a shield precast member in a tunnel, based on a shield precast member assembly measuring device, characterized by, The shield precast component assembly and measurement device includes a protective shell, a distance measurement module and an inclination measurement module respectively disposed in the protective shell; the distance measurement module includes two rangefinders at an angle to each other; the inclination measurement module includes an inclination meter; the shield precast component installation method in the tunnel includes the following steps: (1) Installation of measuring devices: Install a measuring device on each of the beam arms on both sides of the corresponding assembly machine, and ensure that the laser beam in each measuring device can irradiate the tunnel wall, and connect the measuring device to the control terminal via wired / wireless connection. (2) Zero-position measurement: The assembly machine lifts the precast component to be installed and turns on the measuring device. A total station is used to measure the coordinates of the left and right corners of the front end of the precast component in the geodetic coordinate system, the coordinates of any two points on each laser measuring line of the rangefinder and the corresponding rangefinder readings, the height H of the precast component, the inner radius R of the pipe wall, and the zero-position inclinometer reading γ0. (3) Take the midpoint of the line connecting the left and right corners of the front end of the precast component as the origin of the coordinate system and the line connecting the corners as a coordinate axis to establish an independent coordinate system for the precast component. Transform the coordinates of each point obtained in step (2) to the independent coordinate system of the precast component through the transformation parameters of the two coordinate systems, and calculate the slope angle δ between the left and right corners. (4) Zero-point data calculation: Under the independent coordinate system of the prefabricated component, the azimuth angles θ1, θ2, θ3, and θ4 of each measuring line are calculated by inverse coordinate calculation, and the zero-point coordinates (X1, Y1), (X2, Y2), (X3, Y3), (X4, Y4) and zero-point roll angle β0 of each rangefinder are calculated by forward coordinate calculation. (5) Precast component splicing: The precast component is hoisted to the splicing position by the assembly machine; (6) Calculation of measuring points: Based on the zero-position data and the real-time distance data S1, S2, S3 and S4 of each rangefinder, calculate the coordinates of each measuring point on the pipe wall irradiated by each laser beam in the independent coordinate system of the precast component. Calculate the rolling angle β=γ+β0 based on the real-time data γ of the inclinometer. (7) Fit a plane circle at four points. Fit the center coordinates (X0, Y0) of a plane circle passing through each measuring point in the independent coordinate system of the preform. (8) Comparison of center coordinates: Compare the center coordinates of the fitted circle with the center coordinates of the circle corresponding to the proposed installation position, and provide feedback on the position difference information. The assembly machine is then used to adjust the posture of the prefabricated component until the two centers coincide.

2. The method of installing a tunnel shield preform according to claim 1, wherein, The rangefinder is a laser rangefinder, and the protective shell has an exit window at the corresponding position.

3. The method of claim 1, wherein, In step (1), either of the two measuring devices is equipped with only a distance measuring module.

4. The method of installing a pre-fabricated shield in a tunnel according to claim 1, wherein, In step (2), any two points on the laser measuring line are non-coincident and have a certain distance between them.

5. The method of installing a pre-fabricated shield in a tunnel according to claim 1, wherein, In step (4), the zero rolling angle β0 = slope angle δ - zero tilt meter reading γ0.

6. The method of installing a tunnel shield preform according to claim 1, wherein, In step (5), except for the first prefabricated component, the rear ends of the remaining prefabricated components are brought close to the prefabricated components that have been installed.

7. The method of installing a tunnel shield preform according to claim 1, wherein In the step (6), the coordinates of each of the measuring points in the preform independent coordinate system are (X i + S i × COS θ i , Y i + S i × SIN θ i ), wherein the preform independent coordinate system is a front view of the preform, the connecting line of the left and right two corner points of the preform is the positive direction of the Y axis, and the upward direction through the origin is the positive direction of the X axis.

8. The method of installing a tunnel shield preform according to claim 1, wherein, In step (8), the center coordinates of the circle corresponding to the proposed installation location are (RH, 0).

9. The method of installing a tunnel shield preform according to claim 1, wherein, In the step (8), the position difference information includes a left-right movement value L LR = (Y0 x cos β + X0 x sin β), an up-down movement value L UD = (X0 x cos β + Y0 x sin β) - (R - H).

Images