A complex spatial virtual axis coaxiality measuring device

Abstract

The utility model provides a kind of complex space virtual axis coaxality measuring device, belong to building coaxality measurement technical field, the complex space virtual axis coaxality measuring device, including measuring unit, control unit, adjusting unit and reference unit;Measuring unit uses total station scanner;Control unit includes computer, and computer is connected with total station scanner;Adjusting unit includes angle steel, stainless steel plate, adjustable support and adjustable bolt;Reference unit includes first control point and permanent control point;Total station scanner integrates the function of total station and scanner, for importing BIM model;Computer is high-performance industrial computer, with data receiving, processing and graphic display function;Adjustable support is composed of base, screw rod and top seat, base is fixed on hole body bottom plate reinforcement, top seat is used to place angle steel or stainless steel plate, and the lifting of top seat can be realized by adjusting screw rod;The utility model can solve the problem of wind tunnel complex space coaxality guarantee difficulty.

Description

Technical Field

[0001] This utility model belongs to the field of building coaxiality measurement technology, specifically, it relates to a coaxiality measurement device for a complex space virtual axis. Background Technology

[0002] In the field of wind tunnel engineering, the coaxiality of the tunnel structure directly determines the flow stability of airflow within the tunnel. It is a core key indicator for ensuring the aerodynamic performance of the wind tunnel and the accuracy of experimental data. Especially for high-precision experimental equipment such as high-speed wind tunnels and ultra-high-speed wind tunnels, excessive coaxiality deviation can lead to turbulence and flow deviation, seriously affecting the reliability of experimental results. Specifically, the coaxiality deviation of the tunnel structure is defined as the difference between the measured distance and the theoretically designed distance between the inner wall position of each section of the tunnel structure (such as straight sections, oblique sections, curved sections, and contraction sections) and the tunnel axis. The tunnel axis is not a physical entity, but a virtual spatial axis formed by connecting the centroids of the cross-sections of each section of the tunnel. Because this axis has no physical form, it cannot be directly marked or benchmarked using methods such as string lines and layout as in traditional linear structures, posing a fundamental challenge to coaxiality control during construction. In actual construction, tunnels typically involve multiple parts and various structural forms, including fair-faced concrete base slabs, side walls, and cast-in-place slabs suspended from space frames. The forming processes for different parts (such as concrete pouring, formwork support, and space frame lifting) differ, further increasing the complexity of ensuring coaxiality.

[0003] Currently, while the industry has developed some decentralized measures for precision control of different parts of the tunnel, such as using a level to measure the elevation of straight sections and using a general total station to measure the coordinates of simple sections, these measures generally have limitations. On the one hand, there is a lack of an integrated device that can integrate measurement, data analysis, deviation adjustment, and benchmark unification, making it impossible for data from each stage to be efficiently linked. On the other hand, traditional measuring equipment has limited accuracy and cannot meet the high-precision positioning requirements of virtual axes in complex spaces, making it difficult to carry out tunnel civil construction and subsequent subsystem equipment (such as airflow regulation devices and measuring sensors) based on the same baseline. In summary, existing technologies face difficulties in ensuring coaxiality measurement in complex wind tunnel spaces. Utility Model Content

[0004] In view of this, the present invention provides a coaxiality measuring device for a virtual axis in a complex space, which can solve the problem of difficulty in ensuring coaxiality measurement in a complex space of a wind tunnel.

[0005] This utility model is implemented as follows: This utility model provides a coaxiality measuring device for a complex spatial virtual axis, comprising a measuring unit, a control unit, an adjustment unit, and a reference unit; the measuring unit uses a total station scanner; the control unit includes a computer connected to the total station scanner; the adjustment unit includes angle steel, stainless steel plate, adjustable support, and adjustable bolts; the reference unit includes a primary control point and a permanent control point.

[0006] The technical advantages of this invention's coaxiality measurement device for complex spatial virtual axes are as follows: The measurement unit acquires the three-dimensional coordinates of various parts of the tunnel; the control unit processes and analyzes the data and compares it with the BIM model to determine the deviation; the adjustment unit makes precise adjustments based on the deviation; and the reference unit provides a unified measurement reference. This solves the problem of difficulty in ensuring coaxiality caused by the inability to directly lay out virtual axes and the lack of unified references in various construction stages. Through a closed-loop working mode of unified reference, precise measurement, intelligent analysis, and real-time adjustment, efficient control of coaxiality in complex wind tunnel spaces is achieved, providing reliable technical support for tunnel construction and equipment installation.

[0007] Based on the above technical solution, the coaxiality measuring device for complex spatial virtual axes of this utility model can be further improved as follows: The total station scanner integrates the functions of a total station and a scanner. It is used to import BIM models and perform measurements by clicking on the model. The measured coordinates are the three-dimensional coordinates of the measured part.

[0008] The beneficial effects of adopting the above-mentioned improved scheme are as follows: The integrated function of the total station scanner allows for flexible switching according to measurement needs, meeting the measurement requirements of different scenarios. After importing the BIM model, measurement can be performed simply by clicking on the model, directly linking the measured coordinates with the theoretical coordinates of the model. This eliminates the cumbersome coordinate transformation and registration steps in traditional measurement, reducing registration deviations. This feature, combined with the BIM model software of the control unit, enables real-time comparison between measurement data and the theoretical model, quickly obtaining the deviation amount. It solves the problems of low coordinate matching accuracy and poor efficiency in virtual axis measurement, providing high-precision data for the precise operation of subsequent adjustment units.

[0009] Furthermore, the computer is a high-performance industrial computer used for data reception, processing, and graphical display. It compares and analyzes the measured coordinates with the theoretical coordinates in the BIM model and calculates the deviation, and can display the deviation area graphically.

[0010] The beneficial effects of adopting the above-mentioned improved scheme are as follows: By connecting a high-performance industrial computer to a total station scanner, a large amount of measured data can be received quickly. Its powerful data processing capabilities can complete the comparative analysis of measured coordinates and theoretical coordinates of the BIM model in a short time, accurately calculating the deviation. The function of graphically displaying the deviation area can transform abstract deviation data into intuitive images, facilitating operators to quickly locate problem areas. In conjunction with the measurement unit, real-time processing and visualization of measurement data are achieved, solving the problems of slow data processing and unintuitive deviation locations in traditional measurement. This provides clear guidance for targeted adjustments by the adjustment unit, improving the efficiency and accuracy of the entire measurement and adjustment process.

[0011] Furthermore, the angle steel is 5mm thick and is used for controlling the concrete forming surface of straight and oblique sections. The angle steel is spaced 2m apart and is fixed to the adjustable support by welding.

[0012] The beneficial effects of the above-mentioned improved scheme are as follows: By setting 5mm thick angle steel, sufficient rigidity is ensured while resisting disturbances caused by concrete vibration and personnel movement, guaranteeing its own positional stability during construction. With 2m intervals, the angle steel can evenly cover both straight and inclined sections of the base slab, resulting in more balanced control of the concrete forming surface. The angle steel is welded and fixed to the adjustable supports, ensuring a stable connection. When the adjustable supports are adjusted in elevation, the angle steel can move synchronously and precisely. The angle steel and the adjustable supports together form a stable and adjustable control structure, solving the problem of difficulty in controlling the surface accuracy of wide base slabs using only side wall control points. The use of a laser leveling machine running along the angle steel ensures the flatness of the concrete forming surface, meeting the surface accuracy requirements of both straight and inclined sections.

[0013] Furthermore, the stainless steel plate is 5mm thick and 100mm wide, and is processed into an arc-shaped track by laser cutting for controlling the concrete forming surface of the arc segment. The stainless steel plate is reinforced by chemical anchors and supporting steel bars.

[0014] The beneficial effects of the above-mentioned improved scheme are as follows: By laser-cutting a 5mm thick, 100mm wide stainless steel plate into an arc-shaped track, the theoretical profile of the arc segment can be precisely matched. The connection method of chemical anchors and supporting steel bars ensures a firm connection between the stainless steel plate and the base plate, avoiding the possibility of steel plate displacement that might occur with reinforcement by the base plate steel bars. The adjustable bolts on the connecting steel bars, in conjunction with the stainless steel plate, allow for fine adjustment of the steel plate elevation. This structure solves the problem of the complex and difficult-to-precise control of the arc segment profile. By controlling the concrete forming surface through the elevation of the steel plate surface, the accuracy of the concrete surface of the arc segment meets the requirements, reflecting the targeted design for different parts of the tunnel.

[0015] Furthermore, the adjustable support consists of a base, adjustable bolts, and a top seat. The base is fixed to the reinforcing steel bars on the bottom slab of the tunnel, and the top seat is used to place angle steel or stainless steel plates.

[0016] The beneficial effects of adopting the above-mentioned improved scheme are as follows: By fixing the base to the reinforcing steel of the base plate, stable support is provided for the entire support; the top seat bears angle steel or stainless steel plate, and the height of the top seat can be changed by adjusting the bolts, thereby adjusting the elevation of the angle steel or stainless steel plate. When the measuring unit detects a deviation in the elevation of the angle steel or steel plate, the operator can adjust the bolts to raise or lower the top seat until the design elevation is reached. The adjustable support, in conjunction with the angle steel and stainless steel plate, solves the problem of inaccurate elevation control before concrete pouring, realizes flexible adjustment of the support structure in different parts, ensures the accuracy of the subsequent concrete forming surface, and provides a basic guarantee for coaxiality control.

[0017] Furthermore, adjustable bolts are installed at the bottom of the adjustable support for fine-tuning the elevation of the angle steel or stainless steel plate.

[0018] The beneficial effects of adopting the above-mentioned improved scheme are as follows: by fine-tuning the adjustable bolts, the deviation between the angle steel or steel plate and the theoretical elevation can be further reduced. Combined with the adjustable support, it forms a dual adjustment mechanism of "coarse adjustment plus fine adjustment," solving the problem of insufficient accuracy of a single adjustment method. Especially in areas with high precision requirements, such as contraction sections, the fine-tuning effect of the adjustable bolts can control the elevation deviation within a smaller range, ensuring that the accuracy of the concrete forming surface or formwork plate meets the coaxiality requirements, thus improving the adjustment accuracy of the device.

[0019] Furthermore, the primary control points are CPI01 to CPI04, which are set up using high-precision measurement methods; the permanent control points are set on the top surface of the side wall of the corner section and are obtained by measuring the primary control points.

[0020] The beneficial effects of adopting the above-mentioned improved scheme are as follows: The primary control points CPI01 to CPI04, established through high-precision measurement, provide the original benchmark for the entire measurement work. The permanent control points, derived from the primary control points and located on the top surface of the side walls, are less susceptible to construction interference and can remain stable over the long term. Together, they form a unified and stable benchmark system, solving the problems of easily changing benchmarks and inconsistent benchmarks across different stages during construction. Both the tunnel civil engineering construction and the installation of subsystem equipment are based on this benchmark system, ensuring that all work revolves around the same virtual axis, providing a benchmark guarantee for meeting coaxiality design requirements, and demonstrating the systematic and coherent nature of the installation.

[0021] Furthermore, it also includes an observation platform, which is constructed using a steel support frame measuring 2m in length and 2m in width. The height of the steel support platform is greater than 2 / 3 of the height of the tunnel sidewall.

[0022] The beneficial effects of adopting the above-mentioned improved scheme are as follows: The observation platform, erected with a 2m×2m steel support, provides a stable operating space for surveyors and the total station scanner. The platform height is greater than 2 / 3 of the side wall height, solving the problem of poor visibility caused by the dense support structure of the side wall formwork, allowing the scanner to clearly observe all parts of the side wall. The observation platform, in conjunction with the measurement unit, ensures the smooth progress of side wall formwork measurement, improves the reliability of side wall forming surface accuracy control, provides excellent measurement conditions for side wall coaxiality control, and overcomes the limitations of traditional measurement methods in complex environments.

[0023] Furthermore, there are 10-15 observation platforms, evenly distributed between the two side walls inside the cave.

[0024] The beneficial effects of adopting the above-mentioned improved scheme are as follows: With 10-15 evenly distributed observation platforms, the entire tunnel sidewall can be fully covered, ensuring that every template on the sidewall is within the effective measurement range of the scanner. Multiple observation platforms work together to avoid the limited observation range of a single platform, ensuring no blind spots in the sidewall measurement. Working in conjunction with the measurement unit, comprehensive and high-precision measurements of the sidewall can be performed, promptly detecting and reporting deviations in the sidewall template, providing comprehensive data for adjustments, ensuring the sidewall forming surface accuracy meets requirements, and further guaranteeing the overall coaxiality of the tunnel.

[0025] Compared with existing technologies, the beneficial effects of the virtual axis coaxiality measuring device for complex spaces provided by this utility model are as follows: This device, through a total station scanner combined with BIM technology, can directly acquire the three-dimensional coordinates of various parts of the tunnel and compare them with the BIM model in real time, quickly and accurately obtaining the deviation, providing a precise basis for adjustment, and improving measurement accuracy and efficiency. Furthermore, by adjusting components such as adjustable supports and adjustable bolts in the adjustment unit, fine adjustments can be made to the concrete forming surface or formwork surface to ensure that it meets the requirements for surface accuracy and coaxiality. The setting of the benchmark unit ensures that there is a unified benchmark throughout the measurement process, ensuring that the tunnel civil construction and subsystem equipment installation follow the same benchmark line, which is conducive to improving the overall coaxiality of the tunnel. This invention aims to solve the problem of difficulty in ensuring coaxiality in complex spaces of wind tunnels, and provides a virtual axis coaxiality measuring device for complex spaces to achieve precise measurement and control of parts such as the tunnel floor, side walls, and cast-in-place slabs under the grid structure, ensuring that the coaxiality of the tunnel meets the design requirements. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the construction operation of a complex spatial virtual axis coaxiality measuring device; Figure 2 A schematic diagram of the adjustment unit of a complex spatial virtual axis coaxiality measuring device; The attached diagram lists the components represented by each number as follows: 10. Measuring unit; 11. Control unit; 12. Adjustment unit; 121. Angle steel; 122. Stainless steel plate; 123. Adjustable support; 124. Adjustable bolt; 13. Reference unit; 131. Primary control point. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0029] like Figure 1 Figure 2 shows an embodiment of a complex spatial virtual axis coaxiality measuring device provided by this utility model. In this embodiment, it includes a measuring unit 10, a control unit 11, an adjustment unit 12, and a reference unit 13. The measuring unit adopts a total station scanner. The control unit includes a computer, which is connected to the total station scanner. The adjustment unit includes an angle steel 121, a stainless steel plate 122, an adjustable support 123, and an adjustable bolt 124. The reference unit includes a primary control point 131 and a permanent control point.

[0030] The measurement unit can use a Leica MS60 total station scanner; the computer is equipped with BIM modeling software and data processing software.

[0031] In the above technical solution, the total station scanner integrates the functions of a total station and a scanner, and is used to import BIM models. Measurements are performed by clicking on the model, and the measured coordinates are the three-dimensional coordinates of the measured part.

[0032] Furthermore, in the above technical solution, the computer is a high-performance industrial computer used for data reception, processing, and graphic display. It compares and analyzes the measured coordinates with the theoretical coordinates in the BIM model and calculates the deviation, and can display the deviation area in a graphical manner.

[0033] Furthermore, in the above technical solution, the angle steel is 5mm thick and is used for controlling the concrete forming surface of straight and oblique sections. The angle steel is spaced 2m apart and is fixed to the adjustable support by welding.

[0034] Furthermore, in the above technical solution, the stainless steel plate is 5mm thick and 100mm wide, and is processed into an arc-shaped track by laser cutting for controlling the concrete forming surface of the arc segment. The stainless steel plate is reinforced by chemical anchors and supporting steel bars.

[0035] like Figure 2 As shown, in the above technical solution, the adjustable support consists of a base, an adjustable bolt, and a top seat. The base is fixed to the reinforcing steel bars on the bottom plate of the tunnel, and the top seat is used to place angle steel or stainless steel plate.

[0036] Furthermore, in the above technical solution, the adjustable bolt is set at the bottom of the adjustable support for fine-tuning the elevation of the angle steel or stainless steel plate.

[0037] When in use, when the angle steel is welded to the adjustable support, there is an adjustable bolt under the support. When the elevation of the support is higher than the elevation of the plate, the bolt can be adjusted to lower the elevation of the support. When other supports are lower than the elevation of the plate, the bolt can be adjusted to raise the elevation for final measurement of the angle steel elevation.

[0038] Furthermore, in the above technical solution, the primary control points are CPI01 to CPI04, which are set up using high-precision measurement methods; the permanent control points are set on the top surface of the side wall of the corner section and are obtained by measuring the primary control points.

[0039] Furthermore, the above technical solution also includes an observation platform, which is constructed using a steel support frame that is 2m long and 2m wide. The height of the steel support platform is greater than 2 / 3 of the height of the tunnel sidewall.

[0040] Furthermore, in the above technical solution, the number of observation platforms is 10-15, evenly distributed in the middle of the two side walls inside the cave.

[0041] Preferably, the number of observation platforms is 13.

[0042] The following is a specific embodiment of this technical solution: Reference unit layout: Using a high-precision GNSS positioning system (such as Trimble R12i) combined with a total station (such as Leica TS60), the primary control points CPI01 to CPI04 are laid out according to the national second-class surveying standard. During layout, locations with open views and minimal construction interference should be selected, with good visibility between control points, and each control point should be visible to at least two other primary control points. After layout, the control points are measured at least twice, and the average coordinates are calculated to ensure that the mean square error of the plane coordinates of the primary control points is ≤ ±2mm, and the mean square error of the elevation is ≤ ±1mm. After the concrete pouring of the sidewalls at the tunnel corners is completed and reaches 80% of the design strength, permanent control points are established using the primary control points CPI01 to CPI04. A Leica TS60 total station is used with the traverse method for the survey. A permanent control point is marked every 5 meters on the top surface of the sidewalls, for a total of 8 points. After the survey is completed, the closure error of the permanent control points is calculated to ensure that the horizontal closure error is ≤ ±3mm and the vertical closure error is ≤ ±2mm. Once qualified, the permanent control points are fixed and protected using stainless steel embedded parts.

[0043] Observation platform construction: Based on the height of the tunnel sidewalls (assuming a sidewall height of 15m), the observation platform height is determined to be 11m (greater than 2 / 3 of the sidewall height). A steel support frame, 2m long × 2m wide, is fabricated using Q235B steel. The support frame columns are made of Φ80mm × 5mm steel pipe, and the crossbars are made of Φ50mm × 4mm steel pipe. The support frame joints are connected by welding, with a weld height ≥ 6mm.

[0044] Following the principle of uniform distribution, 13 observation platforms were constructed between the two side walls inside the tunnel. The spacing between the platforms was determined based on the tunnel length (assuming a tunnel length of 100m, the platform spacing would be approximately 7.7m). During construction, holes were first drilled in the concrete floor slab of the tunnel using an impact drill, and M16 chemical anchors were inserted. The steel support base was then fixed to the chemical anchors. After fixing, a level was used to calibrate the platform's levelness, ensuring that the platform's horizontal deviation was ≤±0.5mm / m.

[0045] Measurement and control unit installation: Place the total station scanner (Leica MS60) on the observation platform, adjust the scanner's level bubble to the center position, and fix it with a tripod. The bottom of the tripod is connected to the observation platform with bolts to prevent the scanner from shifting during the measurement process.

[0046] A high-performance industrial computer (Advantech IPC-610L, configured with an Intel Core i7-12700 processor, 32GB of RAM, and a 2TB SSD) is placed on a nearby observation platform or temporary control room. A wired connection is established with the total station scanner via a gigabit network cable (if the site environment is complex, an industrial-grade wireless AP can be used to establish a 5.8GHz wireless connection, ensuring a data transmission rate ≥100Mbps). BIM modeling software (such as Autodesk Revit 2024) and data processing software (such as Leica Cyclone REGISTER 360) are installed on the computer, and the complete BIM model of the tunnel (including theoretical coordinates and surface parameters of each part) is imported into the software. Communication debugging between the software and the total station scanner is completed to ensure that the scanner can transmit the measured data to the computer in real time.

[0047] Pre-assembly of the adjustment unit: Pre-fabricated 5mm thick equilateral angle steel (model L50×5) and 5mm thick, 100mm wide 304 stainless steel plate. For the stainless steel plate required for the curved section, the curved section of the tunnel is cut into arc shape using a laser cutting machine (such as Han's Laser G3015) according to the arc parameters of the BIM model of the curved section (assuming the radius of the curved section is 8m and the central angle is 60°), with the cutting accuracy controlled within ±0.1mm. Adjustable support: The base is made of 10mm thick square steel plate (150mm side length), the adjustable screw is made of M20×150mm high strength bolt, and the top is made of 8mm thick rectangular steel plate (200mm long and 100mm wide).

[0048] After the bottom slab reinforcement of the tunnel is tied, adjustable supports are fixed to the bottom slab reinforcement at 2m intervals. The base is fixed to the reinforcement by spot welding, with no less than 4 welding points, each weld point being ≥10mm in length. After fixing, the screw rods are initially adjusted so that the top seat elevation is close to the design elevation (error controlled within ±5mm). A 5mm thick angle steel is placed on the top seat of the adjustable support and fixed to the top seat by spot welding, ensuring that the top surface of the angle steel fits tightly against the top surface of the top seat during welding. Start the full-station scanner, select the theoretical model of the straight section of the base plate in the BIM model, click on the measurement point on the model (select a measurement point every 1m), the scanner will automatically measure the three-dimensional coordinates of the top surface of the angle steel and transmit the data to the computer. The computer uses data processing software to compare the measured coordinates with the theoretical coordinates in the BIM model and calculate the elevation deviation. If the deviation exceeds ±2mm, the operator adjusts the screws of the adjustable support to raise or lower the top support, thereby adjusting the elevation of the angle steel. After adjustment, the measurements are repeated until the elevation deviation of all measurement points is ≤ ±2mm. After the angle steel elevation is adjusted to be qualified, a laser leveling machine (such as SANYS Z25-3) is used to run along the top surface of the angle steel to pour the base slab concrete. During the pouring process, the level of the laser leveling machine is observed in real time to ensure that the top surface of the concrete is flush with the top surface of the angle steel. Adjustable supports and angle steel are pre-installed in the same way as the straight section. Then, the total station scanner is started, the BIM model of the inclined section of the base slab is imported, and the measurement points on the model are clicked (one measurement point is selected every 0.8m) to obtain the measured three-dimensional coordinates of the top surface of the angle steel. The computer compares the measured coordinates with the theoretical coordinates. If a large local deviation is found (such as a deviation of +6mm at a certain point), a coarse adjustment is first made by using the screw of the adjustable support to reduce the deviation to within ±1mm. Then, a fine adjustment is made by using the adjustable bolt (M16×50mm) on the connecting steel bar. The bolt is rotated to change the local elevation of the angle steel until the deviation is ≤±0.5mm. After adjustment, the top surface of the angle steel is scanned again to confirm that the deviation of all measurement points is within acceptable limits. Then, concrete is poured. During the pouring process, a level is used to monitor the elevation of the top surface of the concrete in real time to ensure that it is consistent with the top surface of the angle steel. The prefabricated arc-shaped stainless steel plate is placed on the top seat of the adjustable support and reinforced with chemical anchors (M12×100mm) and supporting steel bars (Φ16mm): holes are drilled every 1m on both sides of the steel plate and chemical anchors are inserted. One end of the supporting steel bar is welded to the chemical anchor and the other end is spot welded to the steel plate. At the same time, adjustable bolts are installed on the supporting steel bars, with the top of the bolts contacting the bottom surface of the steel plate. Start the full-site scanner, import the BIM model of the curved segment, and scan the top surface of the curved steel plate to obtain point cloud data. The computer fits the point cloud data with the BIM model to generate a deviation cloud map. If the deviation in a certain area is -4mm, first adjust the adjustable support screw to raise the steel plate as a whole, and then push the steel plate locally with the adjustable bolts until the deviation is ≤±0.8mm. After the deviation adjustment is qualified, concrete pouring is carried out. During the pouring process, a small-diameter vibrator (Φ30mm) is used to vibrate the concrete to avoid the vibrator colliding with the steel plate and affecting the positional accuracy of the steel plate. The total station scanner is moved to the observation platform, the scanner is started and the side wall BIM model is imported, and the side wall formwork is scanned (the scanning density is no less than 20 points per square meter). The computer compares the scan data with the theoretical model. If the formwork is found to protrude locally (deviation +5mm), the operator adjusts the formwork outward by adjusting the top support screws behind the formwork until the deviation is ≤±1mm. During the side wall concrete pouring process, the formwork is scanned every 30 minutes. If deformation of the formwork due to the lateral pressure of the concrete is detected (e.g., deformation in a certain area reaches +3mm), the pouring personnel are immediately notified to stop pouring, adjust the top support bolts, and resume pouring only after the formwork has returned to the acceptable deviation range. Secondary correction of the tunnel axis is also required. After all parts of the tunnel have been poured with concrete and the curing period has ended, a total station scanner will be used to scan the internal surface of the tunnel. The point cloud density will be no less than 30 points per square meter. The scanned point cloud will then be imported into the BIM model for fitting. The computer analyzes the fitting results using data processing software and selects an optimal axis M0 (the axis that minimizes the coaxiality deviation of each part) as the reference axis of the tunnel. The starting point coordinates (e.g., X=1000.000m, Y=500.000m, Z=10.000m) and elevation parameters of M0 are marked on the BIM model. Using a Leica TS60 total station, based on the M0 parameters marked in the BIM model, the projection lines of M0 were laid out on the bottom slab, side walls, and cast-in-place slabs under the space frame of the tunnel. The projection lines were marked with ink lines, and reflective stickers were affixed to the marked locations as the reference axis for the installation of subsystem equipment. The coaxiality deviation of each section of the corrected tunnel is measured, and a correction report is generated. The report includes the deviation data of each part (e.g., coaxiality deviation of the contraction section ≤ 12mm, straight section ≤ 8mm), and is submitted to the supervision unit for approval. After approval, it will serve as the basis for subsequent construction.

[0049] Secondary correction of the tunnel axis: After the concrete pouring of all parts of the tunnel is completed and the curing period is over, a total station scanner is used to conduct a comprehensive scan of the tunnel's internal surface. The scan point cloud density is no less than 30 points per square meter. The scan point cloud is then imported into the BIM model for fitting. The computer analyzes the fitting results using data processing software and selects an optimal axis M0 (the axis that minimizes the coaxiality deviation of each part) as the reference axis of the tunnel. The starting point coordinates (e.g., X=1000.000m, Y=500.000m, Z=10.000m) and elevation parameters of M0 are marked on the BIM model. Using a Leica TS60 total station, based on the M0 parameters marked in the BIM model, the projection lines of M0 were laid out on the bottom slab, side walls, and cast-in-place slabs under the space frame of the tunnel. The projection lines were marked with ink lines, and reflective stickers were affixed to the marked locations as the reference axis for the installation of subsystem equipment. The coaxiality deviation of each section of the corrected tunnel is measured, and a correction report is generated. The report includes the deviation data of each part (e.g., coaxiality deviation of the contraction section ≤ 12mm, straight section ≤ 8mm), and is submitted to the supervision unit for approval. After approval, it will serve as the basis for subsequent construction.

[0050] Specifically, the principle of this invention is as follows: This device establishes a unified measurement benchmark through a reference unit, ensuring that all measurement work is based on the same baseline. The total station scanner in the measurement unit can accurately acquire the three-dimensional coordinates of various parts of the tunnel. The control unit compares the measured coordinates with the theoretical coordinates in the BIM model and quickly calculates the deviation. For different parts, such as the straight sections, inclined sections, and curved sections of the base plate, as well as the cast-in-place slabs and side walls hanging under the space frame, the adjustment unit makes corresponding adjustments according to the deviation. Through adjustable supports and adjustable bolts, the concrete forming surface or formwork surface can be finely adjusted to control the deviation between the measured value and the theoretical value within the design requirements. During concrete pouring, deformation of the formwork system is monitored in real time to promptly identify and adjust areas exceeding tolerances, preventing deviations in surface accuracy caused by deformation. Finally, through secondary correction of the tunnel's axis and elevation, the optimal reference axis is determined, providing a unified benchmark for the installation of each subsystem, thereby ensuring that the tunnel's coaxiality meets design requirements.

Claims

1. A device for measuring the coaxiality of a complex spatial virtual axis, characterized in that, It includes a measurement unit, a control unit, an adjustment unit, and a reference unit; the measurement unit uses a total station scanner; the control unit includes a computer connected to the total station scanner; the adjustment unit includes angle steel, stainless steel plates, adjustable supports, and adjustable bolts; the reference unit includes primary control points and permanent control points.

2. The coaxiality measuring device for a complex spatial virtual axis according to claim 1, characterized in that, The total station scanner integrates the functions of a total station and a scanner. It is used to import BIM models, and measurements can be taken by clicking on the model. The measured coordinates are the three-dimensional coordinates of the measured part.

3. The coaxiality measuring device for a complex spatial virtual axis according to claim 2, characterized in that, The computer is a high-performance industrial computer used for data reception, processing, and graphical display. It compares and analyzes the measured coordinates with the theoretical coordinates in the BIM model and calculates the deviation, and can display the deviation area graphically.

4. The coaxiality measuring device for a complex spatial virtual axis according to claim 3, characterized in that, The angle steel is 5mm thick and is used for controlling the concrete forming surface of straight and oblique sections. The angle steel is spaced 2m apart and is fixed to the adjustable support by welding.

5. The coaxiality measuring device for a complex spatial virtual axis according to claim 4, characterized in that, The stainless steel plate is 5mm thick and 100mm wide. It is laser-cut into an arc-shaped track for controlling the concrete forming surface of the arc segment. The stainless steel plate is reinforced by chemical anchors and supporting steel bars.

6. The coaxiality measuring device for a complex spatial virtual axis according to claim 5, characterized in that, The adjustable support consists of a base, adjustable bolts, and a top seat. The base is fixed to the reinforcing steel bars on the bottom slab of the tunnel, and the top seat is used to place angle steel or stainless steel plates.

7. The coaxiality measuring device for a complex spatial virtual axis according to claim 6, characterized in that, Adjustable bolts are located at the bottom of the adjustable support for fine-tuning the elevation of angle steel or stainless steel plates.

8. The coaxiality measuring device for a complex spatial virtual axis according to claim 7, characterized in that, The primary control points are CPI01 to CPI04, which are set up using high-precision measurement methods; the permanent control points are set on the top surface of the side wall of the corner section and are obtained by measuring the primary control points.

9. The coaxiality measuring device for a complex spatial virtual axis according to claim 8, characterized in that, It also includes an observation platform, which is constructed using a steel support frame measuring 2m in length and 2m in width. The height of the steel support platform is greater than 2 / 3 of the height of the tunnel sidewall.

10. The coaxiality measuring device for a complex spatial virtual axis according to claim 9, characterized in that, There are 10-15 observation platforms, evenly distributed between the two side walls inside the cave.

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