A long-distance tunnel control through-accuracy measurement and verification system

Abstract

The application discloses a long-distance tunnel control through-accuracy measurement and verification system, and relates to the technical field of tunnel construction measurement. The system comprises a measurement control point, an observation traverse, a traverse stake, a traverse measurement network, the observation traverse being arranged on the traverse stake, one end of the observation traverse being connected with the measurement control point, the other end of the observation traverse being connected with the traverse measurement network, a first ground control network; the system further comprises a pilot hole, a verification traverse, a through tunnel, a horizontal drill hole and a second ground control network; the structure of the second ground control network is the same as that of the first ground control network, the verification traverse is arranged in the pilot hole and along the length direction of the pilot hole, the verification traverse is installed on the traverse stake of the second ground control network, one end of the verification traverse is connected with the measurement control point of the second ground control network, and the other end of the verification traverse is connected with the traverse measurement network through the horizontal drill hole. The application has the effect of verifying the through-accuracy measurement result of the first ground control network.

Description

Technical Field

[0001] This application relates to the technical field of tunnel construction surveying, and in particular to a measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels. Background Technology

[0002] A subway is a type of urban rail transit system, referring to a high-speed, high-capacity, electrically powered rail transit system built in cities. Subway tunnels are typically constructed using the shield tunneling method. By establishing a horizontal control network within the tunnel, the accuracy of the tunnel's centerline can be ensured, allowing the excavation face to be correctly connected according to specified precision. While the shield machine is excavating the tunnel, it simultaneously installs segments on the tunnel wall to support the tunnel and prevent water seepage. However, the length of subway lines between stations is often greater than 3km. When measuring tunnel connection accuracy, the cumulative error will gradually increase, exceeding the tunnel design requirements. If the connection error continues to increase, in long-distance tunnel construction, it will eventually lead to a significant deviation between the shield's centerline and the reserved axis of the next subway station's receiving end, causing the formed tunnel to deviate beyond the limit and posing a risk that the shield will be unable to exit the tunnel.

[0003] In related technologies, a ground control network system is established, including a first traverse network. The first traverse network comprises several first traverses and traverse point groups located at each mileage within the tunnel. Adjacent mileage traverse point groups are located on different sides of the tunnel centerline. Each traverse point group includes two traverse points, denoted as traverse point one and traverse point two. Traverse point one of each traverse point group connects to traverse point one and traverse point two of adjacent traverse point groups via first traverses. Similarly, traverse point two of each traverse point group connects to traverse point one and traverse point two of adjacent traverse point groups via first traverses. When traverse point one and traverse point two of the same traverse point group connect to traverse point one and traverse point two of adjacent traverse point groups, the connecting first traverses intersect, forming a polygonal closed loop. This increases the redundant observations of the ground control network, enhances the traverse closure check conditions, and reduces the impact of angle measurement errors on the tunnel breakthrough error.

[0004] Regarding the aforementioned technologies, although the ground control network system can reduce breakthrough errors, it cannot verify the breakthrough accuracy of the tunnel after measurement, thus making it difficult to control and improve the breakthrough accuracy of long-distance tunnels. Utility Model Content

[0005] In order to verify the tunnel breakthrough accuracy after measurement, and thus control and improve the breakthrough accuracy of long-distance tunnels, this application provides a measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels.

[0006] This application provides a measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels, which adopts the following technical solution:

[0007] A measurement and verification system for controlling the breakthrough accuracy of a long-distance tunnel includes a first ground control network providing coordinate references for tunnel construction and a traverse survey network for monitoring the excavation direction during tunnel construction. The first ground control network includes measurement control points providing the original coordinate references, observation traverses, and traverse stakes serving as nodes for transmitting coordinate information between the ground and underground. The observation traverses are set on the traverse stakes, with one end connected to the measurement control points and the other end connected to the traverse survey network. The system also includes a pilot tunnel for assisting tunnel construction, a verification traverse for verifying the tunnel breakthrough accuracy, a horizontal borehole connecting the tunnel and the pilot tunnel, and a second ground control network for verifying and confirming the measurement results of the initial control network. The structure of the second ground control network is the same as that of the first ground control network. The verification traverse is located inside the pilot tunnel and is set along the length of the pilot tunnel. The verification traverse is installed on the traverse stakes of the second ground control network, with one end connected to the measurement control points of the second ground control network and the other end passing through the horizontal borehole and connected to the traverse survey network.

[0008] By adopting the above technical solution, coordinate benchmarks are provided through measurement control points. Traverse stakes serve as transfer stations for the measurement traverse from the ground to the underground. The observation traverse is connected to the traverse measurement network and the excavation direction is monitored in real time to ensure that the construction proceeds according to the design axis. A second ground control network with the same structure as the first ground control network is added. The verification traverse is connected to the trough-shaped measurement network in the connecting tunnel and the pilot tunnel. The second ground control network forms a closed loop with the traverse measurement network through the verification traverse. After the tunnel penetration accuracy is measured by the first ground control network, the result of the tunnel penetration accuracy measured by the first ground control network is verified, thereby controlling and improving the penetration accuracy of long-distance tunnels.

[0009] Preferably, the traverse survey network includes underground traverse points within the station and traverse points within the tunnel. The underground traverse points within the station are located at the reserved exit of the subway station. Multiple traverse points are set up within the tunnel, and these multiple traverse points are evenly spaced along the length of the tunnel. The underground traverse points within the station and the traverse points within the tunnel near the end of the subway station are mutually visible. The underground traverse points are arranged in two parallel rows along the length of the tunnel, with the two rows of underground traverse points located on both sides of the tunnel. The observation traverse starts from the underground traverse points within the station, connects with multiple traverse points, and returns to the underground traverse points within the station to form a closed loop.

[0010] By adopting the above technical solution, the underground traverse points in the station are in line with the traverse points in the tunnel near the end of the subway station, thereby extending the observation distance of the station and correcting the accuracy of the traverse in the tunnel. Two rows of traverse points are set up in parallel on both sides of the tunnel, and the positional deviation or observation error of the traverse on one side can be detected in time through mutual calibration of the measurement data on both sides. The observation traverse starts from the underground traverse points in the station, connects the traverse points in the tunnel, and returns to the starting point to form a closed loop. The cumulative error is eliminated by the adjustment calculation of the closed traverse, so that the deviation of the tunnel excavation direction can be monitored and corrected in real time.

[0011] Preferably, the observation traverse forms multiple closed loops with the underground traverse points within the station and multiple traverse points within the tunnels; the observation traverse connects to no more than six traverse points within the tunnels in each closed loop.

[0012] By adopting the above technical solution, each closed loop connects no more than 6 traverse points within the tunnel, reducing the superposition effect of angle and distance errors in a single measurement and making the error allocation more accurate during adjustment calculations. The small-scale closed loop facilitates rapid measurement and verification, reduces the impact of factors such as instrument drift and environmental interference in long-distance measurements, and improves measurement efficiency and data reliability.

[0013] Preferably, the horizontal borehole is located at two-thirds of the total length from the tunnel to the next subway station and the distance between the horizontal borehole and the previous subway station does not exceed 3km. Multiple verification points are evenly spaced in a single row inside the pilot tunnel. One end of the verification traverse starts from the measurement control point of the second ground control network. After connecting with multiple verification points, the verification traverse passes through the horizontal borehole and connects with multiple traverse points inside the tunnel to form a closed loop to verify the tunnel penetration accuracy measurement results.

[0014] By adopting the above technical solution, the horizontal borehole is located at two-thirds of the total length of the tunnel to the next subway station, and the distance between the horizontal borehole and the previous subway station is no more than 3km. This location is a key section for controlling the subsequent tunnel breakthrough, and the cumulative error has the greatest impact on the final result. The setting of the horizontal borehole ensures that the error in the transverse breakthrough measurement of the underground tunnel does not exceed ±50mm. The verification point in the pilot tunnel is connected to the traverse point in the tunnel through the horizontal borehole. The verification traverse connects the second ground control network, the verification point, and the traverse point in the tunnel to form a closed loop. By comparing the original data with the secondary measurement of the independent benchmark, the tunnel breakthrough accuracy is checked, which facilitates the timely detection of deviations and allows for adjustment space.

[0015] Preferably, the guide stake includes a tripod, a steel wire, a counterweight, and an oil drum. The two sides of the tripod are fixed to a retaining wall pre-constructed inside the subway station. One end of the steel wire is fixed to the tripod, and the other end of the steel wire is connected to the counterweight and suspended from the tripod. The oil drum is placed below the tripod, and the counterweight is placed in the oil drum and immersed in the oil. The observation guide is set on the tripod, and the steel wire extends the observation guide from the ground to the underground.

[0016] By adopting the above technical solution, the tripod is fixed to the retaining wall of the subway station to provide rigid support; the steel wire is suspended on the tripod, and the weight is completely immersed in the oil drum. The weight ensures that the steel wire is vertical, and the oil drum reduces the swing of the weight through damping; the observation wire extends from the ground to the underground along the steel wire, thereby accurately transmitting the ground coordinates to the underground.

[0017] Preferably, the first ground control network has two guide stakes, which are located at the reserved entrance of the subway station.

[0018] By adopting the above technical solution, the two guide stakes are located at the reserved entrance of the subway station, corresponding to the start and end points of the tunnel construction, forming a symmetrical reference at both ends, preventing the deviation of the tunnel direction caused by the deviation of the single-end reference; the entrance and exit locations have open space, reducing construction interference, facilitating the installation and observation operation of the guide stakes, and ensuring that the coordinate transfer from the ground to the underground can be carried out accurately at both ends of the tunnel.

[0019] Preferably, the first ground control network further includes control stakes that receive and transmit the coordinate information of the measurement control points. Two control stakes are provided, and the two control stakes are located at the subway station near the two traverse stakes. The observation traverse extends to the traverse stakes through the control stakes.

[0020] By adopting the above technical solution, after the control stake receives the coordinate information of the measurement control point, it is transmitted to the traverse stake through the observation traverse. The control stake shortens the transmission distance of the high-precision benchmark and prevents the accuracy decay caused by long-distance transmission. Each level of transmission can be checked independently, further improving the reliability of the coordinate benchmark. Two control stakes are set up for two traverse stakes, and the data between the two can be compared.

[0021] Preferably, the interval between two adjacent guide points in the same row of tunnels is 200-280m.

[0022] By adopting the above technical solution, the interval between adjacent traverse points in the same row is 200-280m, which can ensure the visibility between traverse points and achieve high-frequency direction verification through reasonable density.

[0023] Preferably, a gyroscope for measuring the azimuth angle of a point is installed in the tunnel, and the gyroscope is installed at every 800m interval in the tunnel.

[0024] By adopting the above technical solution, the gyroscope can measure the azimuth angle, periodically correct the azimuth angle deviation of the tunnel excavation line, and prevent the linear accumulation of angle errors during long-distance transmission.

[0025] In summary, this application includes at least one of the following beneficial technical effects:

[0026] 1. Coordinate benchmarks are provided by measurement control points. Traverse stakes serve as transit stations for the survey traverse from the ground to the underground. The observation traverse is connected to the traverse survey network and the excavation direction is monitored in real time to ensure that the construction proceeds according to the design axis. A second ground control network with the same structure as the first ground control network is added. The verification traverse is connected to the trough-shaped survey network in the connecting tunnel and the pilot tunnel. The second ground control network forms a closed loop with the traverse survey network through the verification traverse. After the tunnel penetration accuracy is measured by the first ground control network, the result of the tunnel penetration accuracy measured by the first ground control network is verified, thereby controlling and improving the penetration accuracy of long-distance tunnels.

[0027] 2. The underground traverse points within the station are visible to the traverse points located near the end of the subway station within the tunnel, thereby extending the observation distance of the station and correcting the accuracy of the traverse within the tunnel. Two rows of traverse points are set up in parallel on both sides of the tunnel. By cross-checking the measurement data from both sides, the positional deviation or observation error of the traverse on one side can be detected in a timely manner. The observation traverse starts from the underground traverse points within the station, connects to the traverse points within the tunnel, and returns to the starting point to form a closed loop. The cumulative error is eliminated by the adjustment calculation of the closed traverse, so that the deviation of the tunnel excavation direction can be monitored and corrected in real time.

[0028] 3. The gyroscope can measure the azimuth angle and periodically correct the azimuth angle deviation of the tunnel excavation line to prevent the linear accumulation of angle errors during long-distance transmission. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the structure of the ground control network and the traverse survey network in the embodiments of this application;

[0031] Figure 3 This is a schematic diagram of the structure of the guide stake in the embodiment of this application;

[0032] Figure 4 This is a schematic diagram of the structure of the pilot tunnel, tunnel and horizontal borehole in the embodiments of this application.

[0033] Attached reference numerals: 1. First ground control network; 2. Second ground control network; 3. Traverse survey network; 301. Underground traverse point within the station; 302. Traverse point inside the tunnel; 4. Pilot tunnel; 5. Verification traverse; 6. Horizontal borehole; 7. Survey control point; 8. Observation traverse; 9. Control stake; 10. Traverse stake; 101. Tripod; 102. Steel wire; 103. Weight; 104. Oil drum; 11. Verification point; 12. Gyroscope; 13. Tunnel. Detailed Implementation

[0034] The following is in conjunction with the appendix Figure 1 -Appendix Figure 4 This application will be described in further detail.

[0035] This application discloses a measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels.

[0036] refer to Figure 1 A measurement and verification system for controlling the breakthrough accuracy of a long-distance tunnel 13 includes a first ground control network 1 providing coordinate references, a second ground control network 2 for verifying and confirming the measurement results of the initial control network, a traverse survey network 3 for monitoring the excavation direction during tunnel 13 construction, a pilot tunnel 4 for assisting tunnel 13 construction, a verification traverse 5 for verifying the breakthrough accuracy of tunnel 13, and a horizontal borehole 6 connecting tunnel 13 and pilot tunnel 4. The first ground control network 1 and the traverse survey network 3 work together to measure the breakthrough accuracy of tunnel 13. The horizontal borehole 6 connects tunnel 13 and pilot tunnel 4. The verification traverse 5 is arranged in pilot tunnel 4, with one end connected to the second ground control network 2 and the other end passing through pilot tunnel 4 and horizontal borehole 6 to connect to traverse survey network 3. After the breakthrough accuracy of tunnel 13 is measured by the first ground control network 1, the result of the breakthrough accuracy measurement by the first ground control network 1 is verified, thereby controlling and improving the breakthrough accuracy of the long-distance tunnel 13.

[0037] refer to Figure 1 and Figure 2 The first ground control network 1 includes a measurement control point 7 that provides the original coordinate reference, an observation traverse 8, control stakes 9 that receive and transmit the coordinate information of the measurement control point 7, and traverse stakes 10 that serve as nodes for transmitting coordinate information between the ground and underground. One end of the observation traverse 8 is connected to the measurement control point 7, and the other end of the observation traverse 8 is connected to the traverse measurement network 3. The observation traverse 8 connects the measurement control point 7, control stakes 9, traverse stakes 10, and traverse measurement network 3 into a whole. There are two traverse stakes 10, which are installed at the entrance and exit of the subway station, respectively. There are also two control stakes 9 corresponding to the traverse stakes 10, which are located near the two traverse stakes 10, respectively. The observation traverse 8 is connected to both control stakes 9 and both traverse stakes 10.

[0038] refer to Figure 1 and Figure 3 The guide stake 10 includes a tripod 101, a steel wire 102, a counterweight 103, and an oil drum 104. A square steel bar is installed on each side of the tripod 101 and fixed to the retaining wall. The steel wire 102 is suspended on the tripod 101 by rollers. One end of the steel wire 102 is welded to the top of the tripod 101 and fixed. The other end of the steel wire 102 is tied to the ring at the top of the counterweight 103 and connected to the counterweight 103. The observation guide 8 is also suspended on the tripod 101 and extends to the ground by winding the steel wire 102. The oil drum 104 contains oil, and the counterweight 103 is placed in the oil drum 104 and immersed in the oil.

[0039] The second ground control network 2 also includes measurement control points 7, observation traverses 8, control stakes 9 and traverse stakes 10. The structure of the second ground control network 2 is the same as that of the first ground control network 1.

[0040] The traverse survey network 3 includes underground traverse points 301 within the station and traverse points 302 inside the tunnel. The underground traverse points 301 within the station are located at the exit of the subway station. Multiple traverse points 302 inside the tunnel are set up, and the multiple traverse points 302 inside the tunnel are evenly spaced along the length of the tunnel 13. There is a row of traverse points 302 inside the tunnel on each side of the tunnel 13. The interval between two adjacent traverse points 302 inside the tunnel in the same row is 200-280m. In this embodiment, the interval between two adjacent traverse points 302 inside the tunnel in the same row is 220m.

[0041] The underground traverse point and the traverse point 302 in the tunnel near the end of the subway station in Tunnel 13 are mutually visible, which achieves the purpose of lengthening the observation distance of the station and correcting the accuracy of the traverse in Tunnel 13.

[0042] The observation traverse 8 starts from the underground traverse point 301 in the station and connects with multiple traverse points 302 in the tunnel and returns to the underground traverse point 301 in the station to form multiple closed loops. The cumulative error is eliminated by the adjustment calculation of the closed traverse, so that the deviation of the tunnel 13 excavation direction can be monitored and corrected in real time.

[0043] In each closed loop, the observation traverse 8 connects to no more than six traverse points 302 inside the tunnel, which reduces the superposition effect of angle and distance errors in a single measurement and makes the error distribution more accurate in the adjustment calculation. The small-range closed loop facilitates the rapid completion of measurement and verification, reduces the impact of factors such as instrument drift and environmental interference in long-distance measurements, and improves measurement efficiency and data reliability.

[0044] Multiple verification points 11 are set in a single row at even intervals inside the pilot tunnel 4. One end of the verification traverse 5 starts from the measurement control point 7 of the second ground control network 2. After the verification traverse 5 is connected to the multiple verification points 11, it passes through the horizontal borehole 6 and is connected to the multiple traverse points 302 in the tunnel to form a closed loop to verify the tunnel 13 penetration accuracy measurement results.

[0045] refer to Figure 1 and Figure 4 The horizontal borehole 6 is located at two-thirds of the total length from tunnel 13 to the next subway station, and the distance between the horizontal borehole 6 and the previous subway station is no more than 3km. This position is the key section for controlling the subsequent tunnel 13 before it is completed. The cumulative error has the greatest impact on the final result. The setting of the horizontal borehole 6 ensures that the error in the transverse breakthrough measurement of the underground tunnel does not exceed ±50mm.

[0046] The rock strata where horizontal borehole 6 is located must have good integrity, and should be slightly weathered or moderately weathered rock strata with an RQD value of 88% to 90% or higher, to prevent the risk of formation water jetting during and after drilling.

[0047] Before drilling, surveyors marked the center point of the borehole on the steel pipe segments of the connecting passage, and welded DN200 galvanized steel pipes and flanges. A battery-powered vehicle transported a 150D anchoring drilling rig and a 160KW diesel generator to the drilling location. The drilling angle was determined by pulling lines at both ends based on the markings left by the surveyors on the steel pipe segments and the opposite segments. A φ168 hollow core drill bit was used for drilling, with a core tube length of 1m. Every 500-600mm of drilling, the core was removed and drilling continued until the adjacent line section steel pipe segments were drilled through. The back ribs of the steel pipe segments were cut off, steel pipe flange rings were welded, and gate valves were installed, completing the construction of horizontal borehole 6.

[0048] Gyroscopes 12 are placed every 800m inside tunnel 13. The gyroscopes 12 can measure the azimuth angle and periodically correct the azimuth angle deviation of the tunnel 13 excavation line to prevent the linear accumulation of angle error during long-distance transmission.

[0049] The implementation principle of this application embodiment is as follows: the observation traverse 8 connects the measurement control point 7 with the traverse measurement network 3, and forms multiple closed loops with the underground and station traverse points and the tunnel traverse points 302. The cumulative error is eliminated by the adjustment calculation of the closed traverse, so that the deviation of the tunnel 13 excavation direction can be monitored and corrected in real time; the verification traverse 5 connects the second ground control network 2 with the traverse measurement network 3, and forms a closed loop with the tunnel traverse points 302. After measuring the tunnel 13 penetration accuracy with the first ground control network 1, the tunnel 13 penetration accuracy is verified, thereby controlling and improving the penetration accuracy of the long-distance tunnel 13.

[0050] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A measurement and verification system for controlling the breakthrough accuracy of a long-distance tunnel, comprising a first ground control network (1) providing coordinate reference for tunnel (13) construction and a traverse survey network (3) for monitoring the excavation direction during tunnel (13) construction, wherein the first ground control network (1) comprises a measurement control point (7) providing the original coordinate reference, an observation traverse (8), and traverse stakes (10) serving as nodes for transmitting coordinate information between the ground and underground, wherein the observation traverse (8) is set on the traverse stakes (10), one end of the observation traverse (8) is connected to the measurement control point (7), and the other end of the observation traverse (8) is connected to the traverse survey network (3); characterized in that, It also includes a pilot tunnel (4) for assisting in the construction of the tunnel (13), a verification traverse (5) for verifying the penetration accuracy of the tunnel (13), a horizontal borehole (6) connecting the tunnel (13) and the pilot tunnel (4), and a second ground control network (2) for verifying and confirming the measurement results of the initial control network; the structure of the second ground control network (2) is the same as that of the first ground control network (1), the verification traverse (5) is located inside the pilot tunnel (4) and is set along the length of the pilot tunnel (4), the verification traverse (5) is installed on the traverse stakes (10) of the second ground control network (2), one end of the verification traverse (5) is connected to the measurement control point (7) of the second ground control network (2), and the other end of the verification traverse (5) passes through the horizontal borehole (6) and is connected to the traverse measurement network (3).

2. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 1, characterized in that, The traverse survey network (3) includes underground traverse points (301) within the station and traverse points (302) within the tunnel. The underground traverse points (301) within the station are set at the reserved entrance of the subway station. There are multiple traverse points (302) within the tunnel, which are evenly spaced along the length of the tunnel (13). The underground traverse points (301) within the station and the traverse points (302) within the tunnel (13) near the end of the subway station are mutually visible. The underground traverse points are arranged in two rows parallel to each other along the length of the tunnel (13). The two rows of underground traverse points are located on both sides of the tunnel (13). The observation traverse (8) starts from the underground traverse point (301) within the station, connects with multiple traverse points, and returns to the underground traverse point (301) within the station to form a closed loop.

3. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 2, characterized in that, The observation traverse (8) forms multiple closed loops with the underground traverse points (301) in the station and multiple tunnel traverse points (302); the observation traverse (8) connects to no more than six tunnel traverse points (302) in each closed loop.

4. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 2, characterized in that, The horizontal borehole (6) is located at two-thirds of the total length from the tunnel (13) to the next subway station, and the distance between the horizontal borehole (6) and the previous subway station is no more than 3km. Multiple verification points (11) are evenly spaced in a single row in the pilot tunnel (4). One end of the verification guide (5) starts from the measurement control point (7) of the second ground control network (2). After the verification guide (5) is connected to multiple verification points (11), it passes through the horizontal borehole (6) and is connected to multiple guide points (302) in the tunnel to form a closed loop to verify the tunnel (13) penetration accuracy measurement results.

5. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 1, characterized in that, The guide stake (10) includes a tripod (101), a steel wire (102), a weight (103), and an oil drum (104). The tripod (101) is fixed on both sides of a retaining wall pre-constructed inside the subway station. One end of the steel wire (102) is fixed to the tripod (101), and the other end of the steel wire (102) is connected to the weight (103) and suspended on the tripod (101). The oil drum (104) is placed below the tripod (101), and the weight (103) is placed in the oil drum (104) and immersed in the oil. The observation guide (8) is placed on the tripod (101), and the steel wire (102) extends the observation guide (8) from the ground to the underground.

6. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 5, characterized in that, The first ground control network (1) has two guide stakes (10), and the two guide stakes (10) are located at the reserved entrance of the subway station.

7. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 6, characterized in that, The first ground control network (1) also includes control stakes (9) that receive and transmit the coordinate information of the measurement control points (7). There are two control stakes (9), and the two control stakes (9) are located at the subway station near the two guide stakes (10). The observation guide (8) extends to the guide stakes (10) through the control stakes (9).

8. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 2, characterized in that, The interval between two adjacent guide points (302) in the same row of the tunnel is 200-280m.

9. The measurement and verification system for controlling the breakthrough accuracy of long-distance tunnels according to claim 1, characterized in that, The tunnel (13) is equipped with a gyroscope (12) for measuring the azimuth angle of a point. The gyroscope (12) is set at every 800m interval in the tunnel (13).

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