Special long tunnel control point layout structure and control measurement method

Abstract

The present application relates to the technical field of tunnel engineering, in particular to a special long tunnel control point layout structure and control measurement method, comprising the following steps: according to the field measurement condition, the entrance control points C and D are arranged on a pier, and the entrance direction points A and B can be arranged separately or on a pier. In the present application, based on the "Z" type diamond traverse ring, the forced centering pier is arranged to weaken the influence of instrument centering error, and the work of repeatedly burying control piles is avoided. The centering pier is not easy to be disturbed, and the workload and cost are reduced. The control point arrangement makes the target prism have small interference and large angle, improves the measurement accuracy, the cross arrangement method avoids the influence of side light, ensures the data quality, each control point forms a closed quadrilateral, provides redundant observation values, facilitates the detection of data gross error, and facilitates data comparison and analysis. Through comparison of point coordinates, angles and side lengths, gross errors are found and data are reviewed.

Description

Technical Field

[0001] This invention relates to the field of tunnel engineering technology, and in particular to a control point layout structure and control measurement method for extra-long tunnels. Background Technology

[0002] In civil engineering, tunnel engineering refers to underground passages constructed through methods such as excavation or blasting, used in transportation, water conservancy projects, and underground engineering. Extra-long tunnels are tunnels of considerable length, whose design, construction, and monitoring are relatively complex and challenging. In extra-long tunnel engineering, the layout structure of control points and control measurement methods involve the design and application of the arrangement and measurement methods for these control points. This involves determining the locations of measurement points at various points inside and outside the tunnel to control the accuracy and quality of construction. By rationally arranging control points and using appropriate measuring instruments and techniques, accurate data can be obtained to guide the tunnel construction process.

[0003] In traditional tunnel control point layout structures and control surveying methods, the placement of control points is often limited by terrain and construction conditions, lacking sufficient flexibility in location selection. This can lead to inaccurate control point placement and affect the accuracy of measurement results. Secondly, traditional methods often fail to consider the impact of instrument centering errors, potentially increasing measurement data errors. Furthermore, traditional methods often require repeated installation of control stakes, increasing both workload and cost. Moreover, traditional methods may lead to interference between target prisms, affecting the accuracy of measurement results. Additionally, traditional methods may be affected by lateral refraction, impacting the accuracy of measurement results. Finally, traditional methods often neglect the convenience of data comparison and analysis, potentially leading to difficulties in data verification and affecting the accuracy of measurement results. Therefore, traditional tunnel control point layout structures and control surveying methods have shortcomings in terms of accuracy, efficiency, and cost, requiring improvement. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and to propose a control point layout structure and control measurement method for extra-long tunnels.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a control point layout structure and control measurement method for extra-long tunnels, comprising the following steps:

[0006] Based on the on-site measurement conditions, the control points C and D for entering the tunnel are set on one pier, while the sight points A and B after entering the tunnel can be set separately or on one pier.

[0007] Forced centering piers are embedded in the tunnel wall to form a "Z"-shaped diamond guide loop. Control points are then arranged in pairs along both sides of the tunnel in a "Z" shape, with intervals of 300-600 meters.

[0008] The control network outside the tunnel is constructed using multiple GNSS receivers in a single setup, forming multiple overlapping synchronous triangles as overlapping areas.

[0009] Satellite error data for each control point is obtained by synchronously acquiring satellite signals using a GNSS receiver.

[0010] By using the layout of the "Z"-shaped rhomboid traverse loop, the coordinates, included angles, and side lengths of each control point are compared and analyzed to obtain the comparison results.

[0011] As a further aspect of the present invention, the control point is used to determine the design location of the tunnel and ensure the accuracy of construction, and the view direction point is used to assist in determining the direction of the tunnel.

[0012] As a further embodiment of the present invention, the entrance control points C and D and the entrance backsight direction points A and B form a special quadrilateral, wherein the sum of ∠DAC, ∠ACB, ∠CBD, and ∠BDA of the special quadrilateral is equal to 360°.

[0013] As a further embodiment of the present invention, the side length between the entrance control points C and D and the entrance backsight direction points A and B is the side length of ABCD, wherein the side length of ABCD is greater than 600 meters and the vertical angle of the side length of ABCD is less than 5°.

[0014] As a further aspect of the present invention, based on the on-site measurement conditions, the steps for setting up the tunnel entry control points C and D on one pier, and for setting up the tunnel entry back-view direction points A and B separately or on one pier, are as follows:

[0015] Based on the terrain and design of the tunnel entrance, the optimal pier location is identified using a terrain matching algorithm to set up the entrance control points C and D, and the pier location coordinates are generated.

[0016] Based on the pier location coordinates, the coordinate data of points C and D are determined using an offset algorithm, and points C and D are accurately laid out.

[0017] Based on the tunnel design and actual construction requirements, a construction path optimization algorithm is adopted to determine the best layout method, decide the layout of view direction points A and B, whether they are on the same pier or separate, and generate the layout strategy of points A and B.

[0018] Based on the A and B point placement strategy, the specific coordinate positions of A and B are determined using an offset algorithm, A and B point coordinate data are generated, and A and B points are placed.

[0019] As a further aspect of the present invention, a forced centering pier is embedded in the tunnel wall to form a "Z"-shaped diamond-shaped guide loop. Control points are then arranged in pairs along both sides of the tunnel in a "Z" shape, with intervals of 300-600 meters. The specific steps are as follows:

[0020] Based on the tunnel's design depth and width, a depth calculation algorithm is used to determine the required pier embedment depth and generate forced centering pier depth data.

[0021] Based on the depth data of the forced centering piers, forced centering piers are deployed along the tunnel wall, and a three-dimensional coordinate correction algorithm is used to ensure the vertical deployment of the piers and obtain the coordinate data of the forced centering piers.

[0022] Based on the forced alignment of the pier to form a "Z" shaped path, a path planning algorithm is used to determine the specific path of the traverse loop, and traverse loops are laid along both sides of the tunnel to obtain the "Z" shaped traverse loop path data.

[0023] Based on the "Z"-shaped guide loop path data, control points are set up in pairs along both sides of the tunnel. A point layout interval calculation algorithm is used to ensure that the control point layout interval is within the range of 300-600 meters, and control point layout location data is generated.

[0024] As a further aspect of the present invention, the external control network employs multiple GNSS receivers to form a single network, creating multiple overlapping synchronization triangles. The specific steps for defining the overlapping area are as follows:

[0025] Based on the surrounding terrain and the location of the tunnel entrance, a control network layout optimization algorithm is used to determine the optimal control network layout and generate external control network layout data.

[0026] Based on the layout data of the external control network, at each node of the external control network, a receiver deployment optimization algorithm is used to determine the specific coordinate position of each receiver, deploy GNSS receivers, and generate GNSS receiver position data.

[0027] Start all the GNSS receivers, use the synchronization signal processing algorithm to synchronously construct the control network, ensure the formation of overlapping synchronization triangles, and generate a synchronization triangle dataset.

[0028] As a further aspect of the present invention, the step of obtaining satellite error data for each control point using satellite signals synchronously acquired by a GNSS receiver specifically comprises:

[0029] The GNSS receiver is activated, and a signal acquisition algorithm is used to acquire the satellite signals of each control point in real time as raw satellite signal data.

[0030] Based on the original satellite signal data, an error analysis algorithm is used to compare the signal with the standard value and analyze and calculate the position error of each control point, which is then used as the control point satellite error data.

[0031] As a further aspect of the present invention, the steps for comparing and analyzing the coordinates, included angles, and side lengths of each control point using a "Z"-shaped rhomboid guide loop layout to obtain the comparison results are as follows:

[0032] Based on the "Z"-shaped traverse loop path data and control point layout location data, a theoretical coordinate calculation algorithm is used to obtain the theoretical coordinates of each control point and integrate the theoretical coordinate dataset.

[0033] Using control point satellite error data and a coordinate correction algorithm, the theoretical coordinate dataset is calibrated to obtain the corrected coordinate dataset;

[0034] A difference comparison algorithm is used to compare the theoretical coordinate dataset with the corrected coordinate dataset to obtain the differences in the included angle and side length, and to obtain the coordinate difference analysis results.

[0035] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0036] In this invention, a forced centering pier is used based on a "Z"-shaped rhomboid traverse loop. The instrument is connected to the centering plate via bolts, reducing the impact of instrument centering errors on measurement data. Secondly, this layout avoids the need for repeated control stake installation, as the centering piers are placed on the tunnel lining, making them less susceptible to construction and traffic interference, thus reducing the workload and cost of reinstalling control stakes. Furthermore, the control point arrangement of the "Z"-shaped rhomboid traverse loop minimizes mutual interference between target prisms and results in larger included angles, which is beneficial for measurement accuracy. The crisscrossing arrangement on the left and right sides of the tunnel's forward direction avoids the influence of side refraction, ensuring data quality. Additionally, each control point forms a closed quadrilateral, providing redundant observations and facilitating the detection of gross errors in the measurement data. Finally, this layout facilitates data comparison and analysis. By comparing point coordinates, included angles, and side lengths, gross errors can be visually identified, and data verification can be performed. In conclusion, the "Z"-shaped rhomboid traverse loop has advantages in the application of long tunnels and can provide accurate and reliable measurement results. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the main steps of the present invention;

[0038] Figure 2 This is a detailed schematic diagram of step 1 of the present invention;

[0039] Figure 3 This is a detailed schematic diagram of step 2 of the present invention;

[0040] Figure 4 This is a detailed schematic diagram of step 3 of the present invention;

[0041] Figure 5 This is a detailed schematic diagram of step 4 of the present invention;

[0042] Figure 6 This is a detailed schematic diagram of step 5 of the present invention;

[0043] Figure 7 This is a schematic diagram showing the location of the control points outside the tunnel according to the present invention;

[0044] Figure 8 A schematic diagram showing the location of the control points for the "Z"-shaped rhomboid conductor loop of the present invention;

[0045] Figure 9 This is a schematic diagram of single-station data acquisition for the Z-shaped rhomboid conductor loop of the present invention;

[0046] Figure 10 This is a schematic diagram of the measurement of the "Z"-shaped rhomboid guide ring of the present invention;

[0047] Figure 11 This is a schematic diagram of the closed quadrilateral formed by adjacent points of the "Z"-shaped rhomboid conductor loop of the present invention;

[0048] Figure 12 This is a schematic diagram of the railway tunnel measurement angle according to the present invention. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention 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, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Example

[0051] Please see Figures 1 to 12 This invention provides a technical solution: a layout structure and control measurement method for control points in extra-long tunnels, comprising the following steps:

[0052] Based on the on-site measurement conditions, the control points C and D for entering the tunnel are set on one pier, while the sight points A and B after entering the tunnel can be set separately or on one pier.

[0053] Forced centering piers are embedded in the tunnel wall to form a "Z"-shaped diamond guide loop. Control points are then arranged in pairs along both sides of the tunnel in a "Z" shape, with intervals of 300-600 meters.

[0054] The control network outside the tunnel is constructed using multiple GNSS receivers in a single setup, forming multiple overlapping synchronous triangles as overlapping areas.

[0055] Satellite error data for each control point is obtained by synchronously acquiring satellite signals using a GNSS receiver.

[0056] By using the layout of the "Z"-shaped rhomboid traverse loop, the coordinates, included angles, and side lengths of each control point are compared and analyzed to obtain the comparison results.

[0057] First, by placing the entry control point on a single pier, the influence of instrument error on the mean square error is reduced, improving measurement accuracy. Second, the use of a "Z"-shaped diamond-shaped traverse loop layout allows control points to be paired and intersected along both sides of the tunnel with appropriate spacing, efficiently covering the entire tunnel area. This not only improves deployment efficiency but also optimizes the control point layout and provides redundant observations by forming closed quadrilaterals, facilitating the detection of gross errors in the data. Furthermore, the use of multiple GNSS receivers to construct an external control network and acquire satellite error data provides a precise measurement benchmark. Finally, by comparing and analyzing the coordinates, angles, and side lengths of each control point, gross errors and anomalies can be visually identified, facilitating data verification and correction. In summary, this scheme improves measurement accuracy, efficiency, and reliability, reduces workload and cost, and provides a reliable means for the control and monitoring of extra-long tunnel projects.

[0058] Please see Figure 1 Control points are used to determine the design location of the tunnel and ensure the accuracy of construction. Sight points are used to help determine the direction of the tunnel. The entry control points C and D and the backsight points A and B form a special quadrilateral. Specifically, the sum of ∠DAC, ∠ACB, ∠CBD, and ∠BDA of the special quadrilateral is equal to 360°. The side length between the entry control points C and D and the backsight points A and B is the side length ABCD. The side length of ABCD is greater than 600 meters, and the vertical angle of the side length of ABCD is less than 5°.

[0059] First, the establishment of control points determines the tunnel's designed location, ensuring construction accuracy and project quality. The placement of sight points assists in determining the tunnel's direction, ensuring it advances as intended. Second, the entry control point and the exit sight point form a special quadrilateral with a sum of 360° angles, geometrically ensuring the rationality of the layout. Furthermore, side length constraints require the side length between the entry control point and the exit sight point to be greater than 600 meters to provide sufficient baseline length and guarantee measurement accuracy. Angle constraints also exist, requiring the vertical angle to be less than 5° to ensure measurement stability and accuracy. Overall, the establishment of control points and sight points determines location and direction, ensures construction accuracy, provides accurate measurement benchmarks, and guarantees the reliability and accuracy of measurement data.

[0060] Please see Figure 2 Based on the on-site measurement conditions, the control points C and D for entering the tunnel are set on one pier. The specific steps for setting the sight points A and B after entering the tunnel, either separately or on one pier, are as follows:

[0061] Based on the terrain and design of the tunnel entrance, the optimal pier location is identified using a terrain matching algorithm to set up the entrance control points C and D, and the pier location coordinates are generated.

[0062] Based on the pier location coordinates, the offset algorithm is used to determine the coordinate data of points C and D, and the precise layout of points C and D is carried out.

[0063] Based on the tunnel design and actual construction requirements, a construction path optimization algorithm is adopted to determine the best layout method, decide the layout of view direction points A and B, whether they are on the same pier or separate, and generate the layout strategy of points A and B.

[0064] Based on the placement strategy of points A and B, the specific coordinate positions of A and B are determined using an offset algorithm, the coordinate data of points A and B are generated, and points A and B are then placed.

[0065] First, the optimal pier location is determined using a terrain matching algorithm, ensuring the accurate placement of control points C and D at the tunnel entrance, thereby improving measurement accuracy and reliability. Second, the application of an offset algorithm accurately calculates the coordinates of points C and D, achieving precise placement and further enhancing measurement accuracy. Furthermore, the construction path optimization algorithm determines the optimal placement method and the arrangement of points A and B to meet the needs of tunnel design and actual construction, improving construction efficiency and the rationality of the placement. Finally, the flexibility in placing points A and B allows for selection of the same pier or separate placements based on specific needs, making the measurement layout more flexible and adaptable to different scenario requirements.

[0066] Please see Figure 3The steps involve embedding forced centering piers in the tunnel wall to form a "Z"-shaped diamond-shaped guide loop, and then arranging control points in pairs along both sides of the tunnel in a "Z" shape, spaced 300-600 meters apart.

[0067] Based on the tunnel's design depth and width, a depth calculation algorithm is used to determine the required pier embedment depth and generate forced centering pier depth data.

[0068] Based on the depth data of the forced centering piers, forced centering piers are deployed along the tunnel wall, and a three-dimensional coordinate correction algorithm is used to ensure the vertical deployment of the piers and obtain the coordinate data of the forced centering piers.

[0069] Based on the forced alignment of the central pier to form a "Z" shaped path, a path planning algorithm is used to determine the specific path of the traverse loop, and traverse loops are laid along both sides of the tunnel to obtain the "Z" shaped traverse loop path data.

[0070] Based on the "Z"-shaped traverse loop path data, control points are set up in pairs along both sides of the tunnel. A point layout interval calculation algorithm is used to ensure that the control point layout interval is within the range of 300-600 meters, and control point layout location data is generated.

[0071] First, the depth calculation algorithm ensures the accurate embedment depth of the forced centering piers, thereby ensuring that control points are placed perpendicular to the tunnel wall, improving the accuracy and reliability of the measurement. Second, the three-dimensional coordinate correction algorithm guarantees the accurate vertical placement of the piers, further improving the accuracy of the control point placement. The path planning algorithm determines the specific path of the traverse loop, ensuring its continuity and integrity, making the measurement path reasonable and effective. Furthermore, the control point spacing calculation algorithm ensures that the spacing between control points is within the range of 300-600 meters, resulting in a moderate placement density that meets the requirements of measurement and control.

[0072] Please see Figure 4 The control network outside the cave uses multiple GNSS receivers to form a single network, creating multiple overlapping synchronization triangles. The specific steps for defining the overlapping area are as follows:

[0073] Based on the surrounding terrain and the location of the tunnel entrance, a control network layout optimization algorithm is used to determine the optimal control network layout and generate external control network layout data.

[0074] Based on the layout data of the external control network, a receiver deployment optimization algorithm is used at each node of the external control network to determine the specific coordinate position of each receiver, deploy GNSS receivers, and generate GNSS receiver position data.

[0075] Start all GNSS receivers, use synchronization signal processing algorithms to synchronously construct the control network, ensure the formation of overlapping synchronization triangles, and generate a synchronization triangle dataset.

[0076] First, the control network layout optimization algorithm ensures the optimal layout of control network nodes, taking into account the surrounding terrain and entrance locations of the tunnel, thereby achieving the goal of comprehensive coverage and reasonable deployment. Second, the receiver deployment optimization algorithm ensures the balanced distribution and accurate deployment of receivers, improving the reliability and accuracy of the entire control network. Simultaneously, through a synchronization signal processing algorithm, the synchronous construction of the control network is achieved, forming overlapping synchronization triangles. This construction method provides a highly accurate measurement baseline, further improving the accuracy and reliability of measurements. In summary, the tunnel external control network deployment scheme using multiple GNSS receivers in a single network construction features optimized layout, accurate deployment, and high synchronization, effectively improving measurement efficiency and accuracy.

[0077] Please see Figure 5 The specific steps for obtaining satellite error data for each control point using satellite signals synchronously acquired by a GNSS receiver are as follows:

[0078] Activate the GNSS receiver and use a signal acquisition algorithm to acquire satellite signals from each control point in real time as raw satellite signal data.

[0079] Based on the raw satellite signal data, an error analysis algorithm is used to compare the signal with the standard value and analyze and calculate the position error of each control point, which is then used as the satellite error data of the control points.

[0080] First, position error analysis can provide information about the precise location and measurement quality of each control point. By comparing satellite signals with standard values, the deviation of the control point from the standard position can be calculated, further evaluating the accuracy and reliability of the measurement. Second, satellite error data can be used for data optimization and correction, improving the accuracy and consistency of measurement data. By considering the error data for each control point, measurement results can be improved to better conform to standard values. Furthermore, satellite error data can be used for quality control and verification. By comparing with standard values ​​and expected error ranges, the reasonableness of the measurement results can be verified, and abnormal data or potential problems can be identified in a timely manner.

[0081] Please see Figure 6 Using a "Z"-shaped rhomboid traverse loop layout, the coordinates, included angles, and side lengths of each control point are compared and analyzed. The specific steps to obtain the comparison results are as follows:

[0082] Based on the "Z"-shaped traverse loop path data and control point layout location data, a theoretical coordinate calculation algorithm is used to obtain the theoretical coordinates of each control point and integrate the theoretical coordinate dataset.

[0083] Using control point satellite error data, a coordinate correction algorithm is employed to calibrate the theoretical coordinate dataset and obtain the corrected coordinate dataset.

[0084] A difference comparison algorithm is used to compare the theoretical coordinate dataset with the corrected coordinate dataset to obtain the differences in the included angle and side length, and to obtain the coordinate difference analysis results.

[0085] First, coordinate correction algorithms can improve the accuracy and consistency of measurements by incorporating satellite error data of control points to correct theoretical coordinate datasets. This reduces measurement deviations caused by satellite errors, making the corrected coordinates closer to the true position. Second, by comparing the corrected coordinate dataset with the theoretical coordinate dataset using a difference comparison algorithm, the precision and accuracy of the measurements can be evaluated. Analyzing differences in angles and side lengths can help identify potential problems or anomalies, allowing for appropriate adjustments and corrections. Furthermore, this comparative analysis can be used for quality control and verification of measurement data. By evaluating the results of coordinate difference analysis, the rationality and consistency of the measurement data can be determined, the reliability of the measurements can be verified, and the credibility of the underlying data can be provided.

[0086] Working Principle: Based on on-site measurement conditions, entry control points C and D are placed on a single pier, while sight direction points A and B can be placed separately or on the same pier. Forced centering piers are embedded in the tunnel wall, forming a "Z"-shaped diamond traverse loop. Control points are then intersected along both sides of the tunnel. Multiple GNSS receivers are used to construct an external control network, with overlapping areas forming synchronous triangles. Satellite signals are acquired using GNSS receivers to obtain satellite error data for each control point. Comparative analysis of the control point coordinates, included angles, and side lengths yields comparative results. Further schemes include strategies for determining pier positions and placing sight direction points, as well as determining the placement of piers and traverse loops based on depth calculations and path planning. Optimization of the external control network layout and GNSS receiver placement ensures effective network construction. The entire method, through comprehensive adjustments to the placement of control points and sight direction points, the installation of forced centering piers, the construction of the external control network, and the acquisition and processing of satellite signals, achieves precise measurement and control of extra-long tunnels.

[0087] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A control measurement method for the layout structure of control points in an extra-long tunnel, characterized in that, Includes the following steps: Based on the on-site measurement conditions, the entry control points C and D are placed on the same pier. The sight direction points A and B after entering the tunnel can be placed separately or on the same pier. This process includes: based on the terrain and design of the tunnel entrance, using a terrain matching algorithm, identifying the optimal pier location for placing the entry control points C and D, and generating pier position coordinates; based on the pier position coordinates, using an offset algorithm to determine the coordinate data of points C and D, and accurately placing points C and D; according to the tunnel design and actual construction needs, using a construction path optimization algorithm to determine the optimal placement method, deciding on the placement method of sight direction points A and B, whether they are on the same pier or separate, and generating a placement strategy for points A and B; based on the placement strategy for points A and B, using an offset algorithm to determine the specific coordinate positions of A and B, generating coordinate data for points A and B, and placing points A and B. Forced centering piers are embedded in the tunnel wall to form a "Z"-shaped diamond-shaped traverse loop. Control points are then arranged in pairs along both sides of the tunnel in a "Z" shape, at intervals of 300-600 meters. This process includes: determining the required pier embedment depth using a depth calculation algorithm based on the tunnel's design depth and width, generating forced centering pier depth data; deploying forced centering piers along the tunnel wall based on this depth data, and using a three-dimensional coordinate correction algorithm to ensure the piers' vertical placement, obtaining forced centering pier coordinate data; forming a "Z"-shaped path based on the forced centering piers, using a path planning algorithm to determine the specific path of the traverse loop, deploying the traverse loop along both sides of the tunnel, and obtaining "Z"-shaped traverse loop path data; and based on the "Z"-shaped traverse loop path data, deploying control points in pairs along both sides of the tunnel, using a point placement interval calculation algorithm. The algorithm ensures that the control point deployment interval is within the range of 300-600 meters, generating control point deployment location data. The external control network uses multiple GNSS receivers to form multiple overlapping synchronous triangles as overlapping areas. This includes using a control network layout optimization algorithm based on the surrounding terrain and tunnel entrance location to determine the optimal control network layout and generate external control network layout data. Based on this external control network layout data, at each node location of the external control network, a receiver deployment optimization algorithm is used to determine the specific coordinate position of each receiver, deploying GNSS receivers and generating GNSS receiver location data. All the GNSS receivers are then activated, and a synchronization signal processing algorithm is used to synchronously construct the control network, ensuring the formation of overlapping synchronous triangles and generating a synchronous triangle dataset. Satellite error data for each control point is obtained by synchronously acquiring satellite signals using a GNSS receiver. By using the layout of "Z"-shaped rhomboid traverse loops, the coordinates, included angles, and side lengths of each control point are compared and analyzed to obtain the comparison results.

2. The control point layout structure and control measurement method for extra-long tunnels according to claim 1, characterized in that, The control points are used to determine the design location of the tunnel and ensure the accuracy of construction, while the sight direction points are used to assist in determining the direction of the tunnel.

3. The control point layout structure and control measurement method for extra-long tunnels according to claim 1, characterized in that, The entrance control points C and D, together with the entrance backsight points A and B, form a special quadrilateral. Specifically, the sum of ∠DAC, ∠ACB, ∠CBD, and ∠BDA of the special quadrilateral is 360°.

4. The control point layout structure and control measurement method for extra-long tunnels according to claim 1, characterized in that, The side length between the entrance control points C and D and the entrance backsight direction points A and B is the side length ABCD, where the side length ABCD is greater than 600 meters and the vertical angle of the side length ABCD is less than 5°.

5. The control point layout structure and control measurement method for extra-long tunnels according to claim 1, characterized in that, The specific steps for obtaining satellite error data for each control point using satellite signals synchronously acquired by a GNSS receiver are as follows: The GNSS receiver is activated, and a signal acquisition algorithm is used to acquire the satellite signals of each control point in real time as raw satellite signal data. Based on the original satellite signal data, an error analysis algorithm is used to compare the signal with the standard value and analyze and calculate the position error of each control point, which is then used as the control point satellite error data.

6. The control point layout structure and control measurement method for extra-long tunnels according to claim 1, characterized in that, Using a "Z"-shaped rhomboid traverse loop layout, the coordinates, included angles, and side lengths of each control point are compared and analyzed. The specific steps to obtain the comparison results are as follows: Based on the "Z"-shaped traverse loop path data and control point layout location data, a theoretical coordinate calculation algorithm is used to obtain the theoretical coordinates of each control point and integrate the theoretical coordinate dataset. Using control point satellite error data and a coordinate correction algorithm, the theoretical coordinate dataset is calibrated to obtain the corrected coordinate dataset; A difference comparison algorithm is used to compare the theoretical coordinate dataset with the corrected coordinate dataset to obtain the differences in the included angle and side length, and to obtain the coordinate difference analysis results.

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