Tunnel inverted arch acceptance method

Abstract

The invention discloses an acceptance method for a tunnel inverted arch. The method comprises the steps of 1, designing an acceptance tool; and step 2, surveying and setting out. And step 3, installing and positioning the inverted arch acceptance tool. 4, after the inverted arch acceptance inspection tool is positioned, the inverted arch acceptance inspection tool slowly moves back and forth, and meanwhile, a sensor is adopted for inverted arch contour data collection; 5, processing the data collected by the inverted arch contour to obtain related inverted arch contour parameters, comparing the inverted arch contour parameters with design requirements, and recording a deviation value; 6, for the part, which does not meet the design requirements, in the inverted arch contour parameters, a constructor adjusts the inverted arch according to the deviation report; and 7, after the inverted contour is corrected, the inverted arch acceptance tool is used for conducting contour inspection again, it is ensured that all deviations are within the allowable range, and the construction is finished. The technical problems of large measurement error, low efficiency, strong subjectivity and inaccurate detection result due to the fact that traditional tunnel inverted arch acceptance mainly depends on manual measurement and manual recording are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering construction, and in particular relates to an acceptance method for a tunnel invert. Background Art

[0002] There are five tunnels in a certain project, with lengths of 5652m, 8924m, 9343m, 2395m and 267.9m respectively. The main lithology of the tunnel site is flaky slate, with Grade III surrounding rock accounting for 10% of the whole tunnel; Grade IV surrounding rock accounting for 75% of the whole tunnel; and Grade V surrounding rock accounting for 25% of the whole tunnel. Tunnel excavation adopts manual drilling and blasting excavation. The invert construction adopts a 36m long fully hydraulic self-propelled mobile trestle to cooperate with the construction. During the tunnel construction process, the invert is an important structure supporting the top of the tunnel, and its quality is directly related to the overall stability and safety of the tunnel project. At present, after the completion of the tunnel construction, the acceptance of the tunnel invert mostly relies on manual measurement and manual recording, which has problems such as large measurement error, low efficiency, strong subjectivity and inaccurate detection results, which makes it difficult to meet the needs of modern tunnel construction quality control. Therefore, it is of great significance to develop an accurate, efficient and automated acceptance method for tunnel inverts. Summary of the invention

[0003] The purpose of the present invention is to provide a tunnel invert acceptance method, which aims to solve the technical problems that the traditional tunnel invert acceptance mostly relies on manual measurement and manual recording, and has large measurement errors, low efficiency, strong subjectivity and inaccurate detection results.

[0004] To achieve the above purpose, the present invention adopts the following technical solution.

[0005] A method for accepting a tunnel invert comprises the following steps.

[0006] Step 1: Design acceptance tooling: Design acceptance tooling for the invert according to the design drawings and the requirements of the tunnel invert structure; The inverted arch acceptance tooling comprises an inverted arch acceptance plate, a slide groove and a sensor; the cross section of the inverted arch acceptance plate is adapted to the cross section shape of the designed inverted arch; the inverted arch acceptance plate is installed at the inverted arch at the bottom of the tunnel, and the center line of the inverted arch acceptance plate corresponds to the center line of the tunnel; a shaping rod is installed on the inner side of the inverted arch acceptance plate along the longitudinal interval; the shape of the shaping rod is adapted to the cross section shape of the inverted arch acceptance plate, and the two ends of the shaping rod respectively exceed the two side top edges of the inverted arch acceptance plate; at the top positions of the two ends of the inverted arch acceptance plate and on the side walls on both sides of the tunnel, a limit plate is respectively arranged along the longitudinal full length; a slide groove is arranged on the plate surface of the limit plate along the longitudinal full length; sliding ends are respectively arranged at the two ends of the shaping rod; the sliding end is inserted into the slide groove and slides along the slide groove; a rolling support device is arranged at the bottom of the inverted arch acceptance plate; the sensors are arranged at intervals on the inverted arch acceptance plate for real-time measurement of the geometric shape of the tunnel inverted arch; Step 2: Survey and set out: First, lay out the tunnel centerline, and lay out elevation control lines on the side walls on both sides of the tunnel and at the upper ends of the corresponding invert acceptance plates on both sides; Step 3, installation and positioning of the inverted arch acceptance tooling: the designed inverted arch acceptance plate is set at the inverted arch at the bottom of the tunnel, and the limit plates are installed on the side walls on both sides of the tunnel; then the two ends of the inverted arch acceptance plate are respectively inserted into the slide grooves of the limit plates to ensure the stability and accuracy of the inverted arch acceptance tooling during the installation process; Step 4: Inverted arch profile measurement: After the inverted arch acceptance tool is positioned, it is slowly moved forward and backward, and sensors are used to collect inverted arch profile data; the moving process accurately controls the centerline position of the inverted arch acceptance plate and the elevations at both ends; Step 5, deviation detection and analysis: Process the data collected from the invert profile to obtain relevant invert profile parameters, compare the invert profile parameters with the design requirements, and record the deviation values; Step 6, deviation correction and adjustment: For the part of the inverted arch profile parameters that do not meet the design requirements, the construction personnel will adjust the inverted arch according to the deviation report to ensure that the inverted arch profile meets the design standards; Step seven: After the invert arch profile has been corrected, use the invert arch acceptance tool to check the profile again to ensure that all deviations are within the allowable range. This completes the construction.

[0007] Preferably, the inverted arch acceptance plate is connected to the shaping rod by bolts; an oblique brace is also provided on the inner side of the inverted arch acceptance plate; the oblique brace is connected between the bottom plate and the side wall of the inverted arch acceptance plate.

[0008] Preferably, the rolling support device includes a connecting plate and a rolling sleeve; the connecting plate is arranged at the bottom of the inverted arch acceptance plate and is located on both sides of the tunnel centerline, and the connecting plates on both sides of the central axis are arranged laterally correspondingly; a positioning shaft is detachably connected between the laterally corresponding connecting plates; the rolling sleeve is sleeved on the positioning shaft and can roll on the positioning shaft.

[0009] Preferably, the cross-section of the slide groove is a horizontal U-shape, and clamping edges are respectively provided at the two side ends of the slide groove; the vertical section of the sliding end is arc-shaped, the lower end of the sliding end is connected to the top of the forming rod, and the upper end of the sliding end is provided with an enlarged end, and the enlarged end is clamped in the slide groove.

[0010] Preferably, when laying out the tunnel centerline in step 2, the centerline points are first laid out, and the spacing between adjacent centerline points in the longitudinal direction is not more than 3m. After the laying out is completed, the front and rear centerline points are connected, and the tunnel centerline is drawn using spray paint; then, the elevation control points are laid out on the side walls on both sides, and the spacing between adjacent elevation control points in the longitudinal direction is not more than 3m. The elevation control points on the side walls on both sides are connected using spray paint lines.

[0011] Preferably, in step three, after the inverted arch acceptance tooling is installed, the inverted arch acceptance plate is positioned and calibrated by a measuring tool to ensure that the position and size of the inverted arch acceptance plate are consistent with the geometric position and size of the design drawing.

[0012] Preferably, in step 4, the sensor collects the vertical distance between the inverted arch and the inverted arch acceptance plate at different positions, thereby obtaining the three-dimensional coordinate information of the corresponding points of the inverted arch, and calculating the inverted arch profile parameters through multiple measurement points; the inverted arch profile parameters in step 5 include the width, curvature and height of the corresponding section of the inverted arch.

[0013] Preferably, in step six, the process of correcting the invert profile is specifically as follows: If the invert arch profile is partially under-excavated, it should be treated by supplementary blasting or chipping with a breaker hammer; If over-excavation occurs locally in the arch contour, initial support concrete should be used to fill the gap. It is strictly prohibited to use slag backfill.

[0014] Preferably, after the acceptance is completed in step seven, an acceptance report is generated according to the acceptance process. The acceptance report includes measurement data, deviation analysis, corrective measures and final acceptance conclusion. The acceptance report serves as an important basis for quality control and project management.

[0015] Compared with the prior art, the present invention has the following characteristics and beneficial effects.

[0016] 1. The present invention adopts a specially designed inverted arch acceptance tool, including an inverted arch acceptance plate, a chute, a shaping rod, a sensor and other devices, which can accurately reflect the geometric shape of the tunnel inverted arch and ensure the precision control during the acceptance process. The inverted arch profile is accurately measured by the sensor, and the data collected can further calculate the parameters such as the cross-sectional width, curvature, height of the inverted arch, thereby realizing high-precision acceptance and detection. In addition, the structural designs such as the bolt connection between the inverted arch acceptance plate and the shaping rod, the rolling support device and the chute enable the acceptance tool to be stably and accurately positioned and moved, thereby ensuring the high efficiency and precision of the measuring process.

[0017] 2. The inverted arch acceptance tooling used in the present invention is convenient for real-time data collection and analysis, and the spaced arrangement of sensors enables the geometric data of the inverted arch to be collected in real time at different positions. By obtaining the vertical spacing between the inverted arch and the acceptance plate and calculating the three-dimensional coordinate information of the corresponding points of the inverted arch, the relevant parameters of the inverted arch profile can be obtained quickly and effectively. These real-time collected data can be quickly processed and analyzed, any existing deviations can be detected, and compared with the design requirements, so as to quickly provide an accurate deviation report. Deviation analysis and correction can be efficiently fed back to the construction personnel, further improving the quality control of the acceptance. The method of the present invention is carried out step by step from designing the acceptance tooling, measuring and setting out to deviation correction, and each step strictly stipulates the implementation details. The standardization of the process ensures that each link has strict technical support, greatly reduces errors, and avoids the problems caused by manual measurement and inaccurate positioning in the traditional acceptance process. At the same time, the use of automated sensor measurement and real-time data collection greatly reduces the workload and time cost of manual measurement. The sensor can quickly and accurately collect geometric data at different positions, saving a lot of time compared to the traditional manual measurement method, and reducing the errors caused by manual operation.

[0018] 3. After the completion of the acceptance, the present invention generates an acceptance report including detailed measurement data, deviation analysis, correction measures and final conclusions, which can provide a clear basis for the quality control of the project. These data can serve as an important reference for project management and later maintenance, help improve the transparency of the project, and ensure that quality standards are implemented. And through the acceptance report, project stakeholders can clearly understand every link in the construction process and take timely measures to solve possible problems, thereby enhancing the controllability of project management and the basis for decision-making.

[0019] 4. The present invention adopts customized acceptance tooling to accept the profile of the invert, which can provide more accurate measurement results and avoid errors in traditional manual measurement. The acceptance tooling makes the entire acceptance process more standardized and systematic, reduces the time for repeated measurement and correction, and improves the acceptance efficiency. The tunnel invert acceptance method of the present invention makes each construction link subject to strict quality control, and has significant advantages in improving acceptance accuracy, data collection efficiency, construction quality control, saving time and labor costs, and enhancing engineering controllability and transparency. At the same time, through a strict deviation detection and correction mechanism, it is ensured that the final structure of the tunnel invert meets the design standards, reduces safety hazards, and improves the quality and reliability of the tunnel project. These beneficial effects make this method have a strong promotion value and practical application significance in tunnel engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0021] Figure 1 It is a schematic diagram of the connection structure between the shaping rod and the inverted arch acceptance plate in the present invention.

[0022] Figure 2 It is a schematic diagram of the connection structure between the sliding end and the sliding groove in the present invention.

[0023] Figure 3 It is a structural schematic diagram of the enlarged end being clamped in the slide groove in the present invention.

[0024] Figure numerals: 1 - inverted arch acceptance plate, 2 - slide groove, 3 - sensor, 4 - shaping rod, 5 - limit plate, 6 - sliding end, 7 - connecting plate, 8 - rolling sleeve, 9 - positioning shaft, 10 - clamping edge. DETAILED DESCRIPTION

[0025] like Figure 1-3 As shown, the acceptance method of this tunnel invert includes the following steps.

[0026] Step 1, design acceptance tooling: design an inverted arch acceptance tooling according to the design drawings and the requirements of the inverted arch structure of the tunnel; the inverted arch acceptance tooling includes an inverted arch acceptance plate 1, a slide 2 and a sensor 3; the cross section of the inverted arch acceptance plate 1 is adapted to the cross section shape of the designed inverted arch, and is an arc-shaped plate; the bottom of the inverted arch acceptance plate 1 is substantially parallel to the bottom surface of the tunnel, and the two ends of the inverted arch acceptance plate 1 are bent upward and extend to the side walls on both sides of the tunnel; the inverted arch acceptance plate 1 is installed at the inverted arch at the bottom of the tunnel, and the center line of the inverted arch acceptance plate 1 corresponds to the center line of the tunnel; the inner side of the inverted arch acceptance plate 1 is provided with shaping rods 4 at intervals along the longitudinal direction; the shaping rods 4 are provided at the inner side of the inverted arch acceptance plate 1; the shaping rods 4 are provided ... The shape of the forming rod 4 is adapted to the cross-sectional shape of the inverted arch acceptance plate 1, and the two ends of the forming rod 4 respectively exceed the top edges of the two sides of the inverted arch acceptance plate 1; at the top positions of the two ends of the inverted arch acceptance plate 1, on the side walls on both sides of the tunnel, limit plates 5 are respectively arranged along the longitudinal length; on the plate surface of the limit plate 5, a slide groove 2 is arranged along the longitudinal length; the two ends of the forming rod 4 are respectively provided with sliding ends 6; the sliding end 6 is inserted into the slide groove 2 and slides along the slide groove 2; a rolling support device is arranged at the bottom of the inverted arch acceptance plate 1; the sensors 3 are arranged at intervals on the inverted arch acceptance plate 1 for real-time measurement of the geometric shape of the tunnel inverted arch.

[0027] Step 2, measurement and layout: first, lay out the tunnel centerline, and lay out the elevation control lines on the side walls on both sides of the tunnel, corresponding to the upper ends of the invert acceptance plate 1 on both sides.

[0028] Step three, installation and positioning of the inverted arch acceptance tooling: set the designed inverted arch acceptance plate 1 at the inverted arch at the bottom of the tunnel, and install the limit plates 5 on the side walls on both sides of the tunnel; then insert the two ends of the inverted arch acceptance plate 1 into the slide grooves of the limit plates 5 respectively to ensure the stability and accuracy of the inverted arch acceptance tooling during the installation process, and use measuring tools to position and calibrate the inverted arch acceptance plate to ensure accuracy during the acceptance process.

[0029] Step 4, inverted arch contour measurement: After the inverted arch acceptance tooling is positioned, three auxiliary workers slowly move it back and forth through the rolling support device, and use the sensor 3 to collect the inverted arch contour data; the moving process accurately controls the centerline position of the inverted arch acceptance plate 1 and the elevations at both ends; the centerline position of the inverted arch acceptance plate is accurately controlled to avoid the influence of human deviation.

[0030] Step 5: Deviation detection and analysis: Process the data collected from the invert profile to obtain relevant invert profile parameters, compare the invert profile parameters with the design requirements, record the deviation value, and further analyze the cause of the deviation.

[0031] Step 6, deviation correction and adjustment: For the parts of the invert profile parameters that do not meet the design requirements, the construction personnel adjusted the invert according to the deviation report to ensure that the invert profile meets the design standards. For local defects or parts that do not meet the design requirements, reasonable correction measures such as additional blasting, hammer chiseling, and initial support concrete filling are taken to ensure that the final geometric shape of the invert meets the design standards and enhance the stability and safety of the project. In particular, when correcting the deviation, it is strictly stipulated that the use of slag backfill is not allowed, which avoids the hidden dangers that may be caused by the use of unqualified materials and further improves the quality of the project.

[0032] Step seven: After the invert arch profile has been corrected, use the invert arch acceptance tool to check the profile again to ensure that all deviations are within the allowable range. This completes the construction.

[0033] In this embodiment, the inverted arch acceptance plate 1 and the shaping rod 4 are connected by bolts; a diagonal brace is also provided on the inner side of the inverted arch acceptance plate 1; the diagonal brace is connected between the bottom plate and the side wall of the inverted arch acceptance plate 1. The inverted arch acceptance plate 1 is made of steel plate or aluminum alloy plate, which has good durability and stability; the diagonal brace of the inverted arch acceptance plate 1 is processed by Φ22 threaded steel. The shaping rod 4 is made of section steel.

[0034] In this embodiment, the rolling support device includes a connecting plate 7 and a rolling sleeve 8; the connecting plate 7 is arranged at the bottom of the arch acceptance plate 1 and on both sides of the tunnel centerline, and the connecting plates 7 on both sides of the central axis are arranged laterally correspondingly; a positioning shaft 9 is detachably connected between the laterally corresponding connecting plates 7; the rolling sleeve 8 is sleeved on the positioning shaft 9 and can roll on the positioning shaft 9, and the rolling sleeve 8 adopts a 2cm galvanized steel pipe.

[0035] In this embodiment, the cross-section of the slide 2 is a horizontal U-shape, and clamping edges 10 are respectively provided at the two side ends of the slide 2; the vertical section of the sliding end 6 is arc-shaped, the lower end of the sliding end 6 is connected to the top of the forming rod 4, and the upper end of the sliding end 6 is provided with an enlarged end head, and the enlarged end head is clamped in the slide 2; the forming rod 4 is made of steel rod segments spliced ​​together, and adjacent steel rod segments are welded or bolted.

[0036] In this embodiment, when laying out the center line of the tunnel in step 2, the center line points are first laid out, and the spacing between adjacent center line points in the longitudinal direction is not more than 3m. After the laying out is completed, the front and rear center line points are connected, and the center line of the tunnel is drawn with spray paint; then, the elevation control points are laid out on the side walls on both sides, and the spacing between adjacent elevation control points in the longitudinal direction is not more than 3m. The elevation control points on the side walls on both sides are connected with spray paint lines; ensure accuracy and eye-catchingness to facilitate the determination of the position of the large-scale tooling.

[0037] In this embodiment, in step three, after the inverted arch acceptance tooling is installed, the inverted arch acceptance plate 1 is positioned and calibrated by measuring tools (such as a total station, a level, etc.) to ensure that the position and size of the inverted arch acceptance plate 1 are consistent with the geometric position and size of the design drawing.

[0038] In this embodiment, in step 4, the sensor collects the vertical distance between the inverted arch and the inverted arch acceptance plate 1 at different positions, thereby obtaining the three-dimensional coordinate information of the corresponding points of the inverted arch, and calculating the inverted arch contour parameters through multiple measuring points; the inverted arch contour parameters in step 5 include the width, curvature and height of the corresponding section of the inverted arch.

[0039] In this embodiment, in step 6, the process of correcting the invert profile is specifically as follows: If the invert arch profile is partially under-excavated, it should be treated by supplementary blasting or chipping with a breaker hammer; If over-excavation occurs locally in the invert profile, initial support concrete shall be used to fill the gap. Backfilling with slag is strictly prohibited.

[0040] In this embodiment, after the acceptance is completed in step seven, an acceptance report is generated according to the acceptance process. The acceptance report includes measurement data, deviation analysis, corrective measures and final acceptance conclusion. The acceptance report serves as an important basis for quality control and project management.

[0041] In this embodiment, the side of the inverted arch acceptance plate 1 close to the tunnel wall is the outer side, and the side of the inverted arch acceptance plate 1 away from the tunnel wall is the inner side.

[0042] In this embodiment, a through hole is opened on the connecting plate 7; both ends of the positioning shaft 9 are respectively provided with threads, and the ends of the positioning shaft 9 are correspondingly inserted into the through hole and fixed by double nuts.

[0043] In this embodiment, a laser is arranged at the central axis of the plate surface of the inverted arch acceptance plate 1. During the movement of the inverted arch acceptance plate 1, the laser emitted by the laser is kept on the same vertical plane as the central axis of the tunnel, thereby ensuring the position of the inverted arch acceptance plate 1 at all times.

[0044] The above embodiments are not exhaustive of specific implementation methods, and there may be other embodiments. The above embodiments are intended to illustrate the present invention rather than to limit the protection scope of the present invention. All applications derived from simple variations of the present invention fall within the protection scope of the present invention.

Claims

1. A method for acceptance of a tunnel invert, characterized in that: The steps include: Step 1: Design acceptance tooling: Design acceptance tooling for the invert according to the design drawings and the requirements of the tunnel invert structure; The inverted arch acceptance tool comprises an inverted arch acceptance plate (1), a slide groove (2) and a sensor (3); the cross section of the inverted arch acceptance plate (1) is adapted to the cross section shape of the designed inverted arch; the inverted arch acceptance plate (1) is installed at the inverted arch at the bottom of the tunnel, and the center line of the inverted arch acceptance plate (1) corresponds to the center line of the tunnel; shaping rods (4) are installed on the inner side of the inverted arch acceptance plate (1) along the longitudinal interval; the shape of the shaping rods (4) is adapted to the cross section shape of the inverted arch acceptance plate (1), and the two ends of the shaping rods (4) respectively extend beyond the two sides of the inverted arch acceptance plate (1). The top edge of the inverted arch acceptance plate (1) is provided with a limit plate (5) at the top positions of both ends of the inverted arch acceptance plate (1) and on the side walls on both sides of the tunnel respectively along the longitudinal length; a slide groove (2) is provided on the plate surface of the limit plate (5) along the longitudinal length; sliding ends (6) are provided at both ends of the shaping rod (4); the sliding ends (6) are inserted into the slide groove (2) and slide along the slide groove (2); a rolling support device is provided at the bottom of the inverted arch acceptance plate (1); the sensors (3) are arranged at intervals on the inverted arch acceptance plate (1) for real-time measurement of the geometric shape of the tunnel inverted arch; Step 2, measurement and setting out: first, the tunnel centerline is set out, and elevation control lines are set out on the side walls on both sides of the tunnel, corresponding to the upper ends of the invert acceptance plate (1) on both sides; Step 3, installation and positioning of the inverted arch acceptance tooling: the designed inverted arch acceptance plate (1) is set at the inverted arch at the bottom of the tunnel, and the limit plates (5) are installed on the side walls on both sides of the tunnel; then the two ends of the inverted arch acceptance plate (1) are respectively inserted into the slide grooves of the limit plates (5) to ensure the stability and accuracy of the inverted arch acceptance tooling during the installation process; Step 4: measuring the profile of the inverted arch: after the inverted arch acceptance tool is positioned, three auxiliary workers slowly move it forward and backward through the rolling support device, and use the sensor (3) to collect the profile data of the inverted arch; the centerline position and the elevations of the two ends of the inverted arch acceptance plate (1) are accurately controlled during the movement process; Step 5, deviation detection and analysis: Process the data collected from the invert profile to obtain relevant invert profile parameters, compare the invert profile parameters with the design requirements, and record the deviation values; Step 6, deviation correction and adjustment: For the part of the inverted arch profile parameters that do not meet the design requirements, the construction personnel will adjust the inverted arch according to the deviation report to ensure that the inverted arch profile meets the design standards; Step seven: After the invert arch profile has been corrected, use the invert arch acceptance tool to check the profile again to ensure that all deviations are within the allowable range. This completes the construction.

2. The acceptance method for tunnel invert according to claim 1, characterized in that: The inverted arch acceptance plate (1) and the shaping rod (4) are connected by bolts; an inclined brace is also provided on the inner side of the inverted arch acceptance plate (1); and the inclined brace is connected between the bottom plate and the side wall of the inverted arch acceptance plate (1).

3. The acceptance method for tunnel invert according to claim 1, characterized in that: The rolling support device comprises a connecting plate (7) and a rolling sleeve (8); the connecting plate (7) is arranged at the bottom of the inverted arch acceptance plate (1) and located on both sides of the tunnel centerline, and the connecting plates (7) on both sides of the centerline are arranged in a transversely corresponding manner; a positioning shaft (9) is detachably connected between the transversely corresponding connecting plates (7); the rolling sleeve (8) is sleeved on the positioning shaft (9) and can roll on the positioning shaft (9).

4. The acceptance method for tunnel invert according to claim 1, characterized in that: The cross section of the slide groove (2) is in a horizontal U-shape, and clamping edges (10) are respectively provided at the two side ends of the slide groove (2); the vertical cross section of the sliding end (6) is arc-shaped, the lower end of the sliding end (6) is connected to the top of the shaping rod (4), and the upper end of the sliding end (6) is provided with an enlarged end, and the enlarged end is clamped in the slide groove (2).

5. The inspection and acceptance method for a tunnel invert according to claim 1, characterized in that: When laying out the tunnel centerline in step 2, first lay out the centerline points. The distance between adjacent centerline points in the longitudinal direction shall not exceed 3m. After the layout is completed, connect the front and rear centerline points, and use spray paint to draw the tunnel centerline; then lay out the elevation control points on the side walls on both sides. The distance between adjacent elevation control points in the longitudinal direction shall not exceed 3m, and use spray paint lines to connect the elevation control points on the side walls on both sides.

6. The acceptance method for tunnel invert according to claim 1, characterized in that: Step 3: After the inverted arch acceptance tooling is installed, the inverted arch acceptance plate (1) is positioned and calibrated by using a measuring tool to ensure that the position and size of the inverted arch acceptance plate (1) are consistent with the geometric position and size of the design drawing.

7. The acceptance method for tunnel invert according to claim 1, characterized in that: In step 4, the sensor collects the vertical distances between the inverted arch and the inverted arch acceptance plate (1) at different positions, thereby obtaining the three-dimensional coordinate information of the corresponding points of the inverted arch, and calculating the inverted arch profile parameters through multiple measurement points; the inverted arch profile parameters in step 5 include the width, curvature and height of the corresponding section of the inverted arch.

8. The inspection and acceptance method for tunnel inverts according to claim 1, characterized in that: In step 6, the process of correcting the invert profile is as follows: If the invert arch profile is partially under-excavated, it should be treated by supplementary blasting or chipping with a breaker hammer; If over-excavation occurs locally in the invert profile, primary support concrete shall be used to fill the gap.

9. The method for acceptance of a tunnel invert according to claim 1, characterized in that: After the acceptance is completed in step seven, an acceptance report is generated according to the acceptance process. The acceptance report includes measurement data, deviation analysis, corrective measures and final acceptance conclusion. The acceptance report serves as an important basis for quality control and project management.

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