Suspension casting construction method using underneath type bridge arch ring

Abstract

The invention belongs to the technical field of intelligent arch bridge construction control, and discloses a cantilever casting construction method using an underneath type bridge arch ring. Firstly, a Beidou base station is arranged on a bridge site shoreside bearing platform, a fixed Beidou positioning terminal is arranged on a bridge main tower, a three-dimensional coordinate system is established, and coordinates of target positions of all pouring sections are calculated. A positioning terminal is installed on the underneath type hanging basket, actual position coordinates are obtained, and a digital twinborn model is constructed. Comparing the actual coordinate with the target coordinate, and if a difference value does not exceed a first preset range and meets a global adjustment condition, adjusting to obtain an adjustment instruction; and if the difference exceeds the range, marking a difference point to be adjusted, performing statistical analysis to generate a difference data set, generating a pre-adjustment instruction according to the difference data set, and pre-adjusting the model. And comparing the pre-adjustment model with the target coordinate, if the pre-adjustment difference value does not exceed a smaller second preset range, outputting an adjustment instruction, and adjusting the hanging basket according to the instruction. The method aims at solving the problems that existing cable-stayed hanging cantilever pouring depends on a local total station and manual measurement, full-bridge real-time three-dimensional coordinate reference cannot be provided, and the arch bridge line shape is difficult to control due to error accumulation.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent bridge construction control, and particularly to a cantilever casting construction method using a lower-mounted bridge arch ring. Background Art

[0002] The construction technology of arch bridges has a long history. Arch bridges have a history of more than 2,500 years in China. With the development of the economy, the application of high-strength and high-quality materials, the development of design theories, and the application of computer technology have promoted the development of new construction techniques and methods. Through years of practice and exploration, the development of arch bridge construction technology is mainly divided into scaffolding and non-scaffolding construction methods. The non-scaffolding construction has a wider application range, but the construction process is relatively complex and the technical difficulty is relatively large. In the construction of long-span arch bridges, the cantilever casting method is widely used due to its advantages such as high construction flexibility and no need for scaffolding. The cantilever construction method of reinforced concrete arch bridges is divided into two categories: the cantilever assembly method and the cantilever casting method. The cantilever casting method mainly uses a hanging basket for cantilever casting construction. The existing hanging baskets include upper-mounted hanging baskets and lower-mounted hanging baskets. The upper-mounted hanging basket moves on the track on the bridge deck as a whole and then is fixed. Its structure is relatively stable and the position prediction is relatively easy to judge. However, it occupies the space on the bridge deck. Therefore, the construction space is limited during the cantilever casting of arch bridges, and it is not suitable for the cantilever casting construction of arch bridges. As Figure 4 shown, the suspension arm of the lower-mounted hanging basket is arranged in the middle of the hanging basket and can move on the track. The end is used as a fulcrum to contact the bottom of the cantilever to form a support, and the attitude of the hanging basket is adjusted by the oil cylinder at the end fulcrum. However, its structural stability is not as good as that of the upper-mounted hanging basket. Therefore, precise adjustment is required every time it advances forward. Using total station and manual measurement is prone to error accumulation. However, precisely because the lower-mounted hanging basket occupies less upper space, has a large adjustment range, and is suitable for curved alignments, etc., it is suitable for the cantilever casting of the arch ring. It has become an important choice for the construction of arch ribs in mountainous valleys and cross-river areas.

[0003] Chinese Patent with Publication No. CN115162211B discloses a cantilever casting construction method for the main arch ring of a reinforced concrete arch bridge. It uses the inclined cable buckling and cantilever casting construction technology to build the bridge. By setting a front fulcrum on the lower-mounted hanging basket and using the arch ring and the buckling cables to jointly bear the load, the structural stability is improved. The cantilever section is a truss structure during the inclined climbing process of the hanging basket, solving problems such as low stiffness of the hanging basket in conventional technologies and poor stability during the walking process. Although the problem of the walking stability of the hanging basket is solved, it still relies on local total station and manual measurement, there are errors and it cannot provide a real-time three-dimensional coordinate reference for the whole bridge. The occlusion of the lower-mounted hanging basket makes it difficult for local measuring points to capture the dynamic alignment of the whole bridge in a timely manner, and the errors accumulate with each segment, ultimately resulting in a deviation in the mid-span plane; making it difficult to control the alignment of the arch bridge and posing a greater construction risk. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the technical problem solved by the present invention is to provide a cantilever casting construction method using an under-mounted bridge arch ring, so as to solve the problem that in the existing under-mounted hanging basket construction method of cable-stayed buckling and cantilever casting, relying on local total stations and manual measurements, it is impossible to provide a real-time three-dimensional coordinate reference for the whole bridge, and the error accumulates with the segments, making it difficult to control the alignment of the arch bridge.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is: a cantilever casting construction method using an under-mounted bridge arch ring, including the following steps;

[0006] S100: Set up a Beidou base station on the abutment of the bridge site, and set a fixed Beidou positioning terminal at the upper end of the main tower of the bridge as a reference point. Establish a three-dimensional coordinate system based on the reference point, and calculate the target position coordinates of each casting segment of the arch bridge according to the three-dimensional coordinate system;

[0007] S200: Install a hanging basket Beidou positioning terminal on the under-mounted hanging basket to obtain the actual position coordinates of the current segment to be cast; and obtain the three-dimensional data of the arch bridge through unmanned aerial vehicle surveying and mapping, and construct a digital twin model of the arch bridge based on the actual position coordinates and the three-dimensional data;

[0008] S300: Compare and analyze the actual position coordinates with the target coordinates to obtain difference data, and judge whether the difference data exceeds the first preset difference range. If not, judge whether the current segment meets the global adjustment condition. If so, perform global adjustment on the current segment and calculate the adjustment instruction, and execute step S600; if so, mark the point where the difference data exceeds the first preset difference range as the point to be adjusted;

[0009] S400: Statistically analyze the number, position and difference value of the points to be adjusted to generate a difference data set, generate a pre-adjustment instruction according to the difference data set, and pre-adjust the digital twin model of the arch bridge according to the pre-adjustment instruction to generate a pre-adjusted arch bridge model;

[0010] S500: Compare the coordinates of the pre-adjusted arch bridge model with the target position coordinates to obtain pre-adjusted difference data, and judge whether the pre-adjusted difference data exceeds the second preset difference range, and the second preset difference range is smaller than the first preset difference range; if so, mark the point where the difference data exceeds the second preset difference range as the point to be adjusted, and return to execute step S400. If not, output the pre-adjustment instruction as the adjustment instruction;

[0011] S600: Adjust the hanging basket according to the adjustment instruction.

[0012] The beneficial effects of this solution are:

[0013] 1. Traditional arch bridge construction monitoring relies on total stations and manual measurement, which has problems such as data update lag and blind spots caused by hanging basket obstruction, which easily leads to error accumulation. This solution uses the Beidou satellite positioning system to collect the three-dimensional coordinate benchmark of the arch bridge under construction in real time, obtain the coordinate data of the actual arch bridge under construction, and eliminate the disadvantage of traditional monitoring that cannot be monitored in real time;

[0014] 2. A high-precision digital twin model is constructed based on Beidou real-time coordinate data. The corrected pre-adjustment instructions are obtained by comparing the digital twin model coordinate data with the target coordinate data. Different from the traditional trial-and-error entity adjustment, this solution introduces a virtual pre-adjustment verification mechanism: the instruction execution effect is simulated in the digital space, and the adjustment strategy is iteratively optimized through the pre-adjustment model until the accuracy requirements are met and then the entity control adjustment instructions are output, thereby ensuring the reliability of the adjustment instructions; a virtual pre-adjustment arch bridge model is constructed for verification to avoid the complexity of repeated adjustments of the entity structure, greatly shorten the verification cycle and reduce the trial-and-error cost, and realize the controllability and reversibility of the construction process;

[0015] 3. During the construction of the arch bridge, even if each segment does not exceed the first preset difference range, there are still cumulative errors in the cast segments. If the cumulative error value is not corrected in time, it will exceed the preset difference range, resulting in a large error in the linear shape of the entire bridge; therefore, in order to address the hidden danger of local compliance but global error accumulation in the construction of multiple segments, the global adjustment operation is further performed on the current segment that does not exceed the preset difference range but satisfies the global adjustment, and the parameters of the constructed segments are collaboratively optimized, and the influence of historical errors is eliminated through reverse compensation. This technology blocks the error chain transmission from the root, ensures that the linear shape of the entire bridge always converges to the design axis, and solves the problem of "local compliance and overall inaccuracy" of the traditional method.

[0016] Further, the specific steps of the global adjustment in step S300 are as follows:

[0017] S301: Determine whether the segment type of the current segment N belongs to the segment to be corrected. The segment to be corrected includes the main correction segment and the fine adjustment segment. If it is judged to be yes, the adjustment instruction is calculated according to the segment type; if it is judged to be no, the absolute value of the deviation of the current segment N |Δ n When | is greater than the tightening threshold, or the total bridge deviation |ΔS| is greater than the set deviation threshold, a global adjustment is performed;

[0018] S302: Mark the current segment n as the reference segment, the n+1 segment as the main correction segment, and the n+2 segment as the fine adjustment segment; then the mold correction amount of the n+1 segment is: C n+1 =-k·Δ n or C n+1 =-k·ΔS; the correction amount of the mold erection of the n+2th segment is: C n+2 =-(1-k)·Δn or C n+2 = -(1 - k)·ΔS; and the cumulative error of three segments is satisfied: Δ n + C n+1 + C n+2 = 0 or ΔS + C n+1 + C n+2 = 0;

[0019] The segments are adjusted by judging whether the current segment error is greater than the tightening threshold; even when the current segment error is less than the tightening threshold, but the cumulative deviation of the whole bridge has exceeded the set deviation threshold, the global adjustment operation is also performed, so that the error of the whole bridge will not accumulate, resulting in the final arch bridge alignment exceeding the error range. And the segment error is adjusted according to the calculation formula of the current segment type, realizing the zeroing of the error within three segments, that is, avoiding too large adjustment amount of a single segment and realizing the error correction in a short time.

[0020] Furthermore, the specific steps of the global adjustment in step S300 are as follows;

[0021] S311: Judge that the absolute value of the current segment deviation is greater than the tightening threshold, or the cumulative deviation of the whole bridge is greater than the set deviation threshold, then perform the global adjustment;

[0022] S312: Establish a dynamic correction model for the linkage of all bridge segments; state vector: X n = [d1, d2,..., d n T ; observation vector: L n = [Δ1, Δ2,..., Δ n T ; error equation: l n = H n ·X n + V n ;

[0023] Among them, Hn is the segment influence matrix, and Vn is the observation noise matrix; where H ij is calculated by the following formula;

[0024]

[0025] S313: Calculate the least squares solution;

[0026]

[0027] d i is the correction amount of a single segment; w ik is the weight coefficient, which decays with the segment distance;

[0028] ​​S314: When adding the (n + 1)-th segment, update X using the recursive least squares method n+1 , and the formula is as follows;

[0029] X n+1 = X n - K n+1 (H n+1 ·X n - Δ n+1 )

[0030] where K n+1 is the gain matrix.

[0031] Adopt a dynamic global adjustment scheme without limiting the number of segments, introduce the least squares method, use the coordinate deviations of all measuring points on the entire bridge as observed values, establish an error equation, and solve the correction amounts of each segment; use recursive least squares to gradually update the correction amounts instead of recalculating the entire bridge every time, reducing the calculation amount and having a fast response speed, meeting the fast response requirements of on-site construction; through the state space model + recursive least squares, it is realized that for each newly added segment, the correction amounts of the entire bridge are automatically updated without waiting for a fixed number of segments. The deviation of a single segment can trigger global adjustment, and the influence weights between segments are considered. For example, the deviation at the proximal end has a greater influence, avoiding over-adjustment at the "far end" during correction.

[0032] Furthermore, the correction amount of a single segment |d i | ≤ α, where α is the maximum stroke of the hanging basket oil cylinder; if it exceeds the limit, it will be corrected in multiple rounds. The correction amount of a single segment matches the oil cylinder stroke, avoiding equipment damage due to overload; fine-tuning in multiple rounds when exceeding the limit can not only protect the mechanical structure but also make the error gradually zero with the progress of pouring, avoiding the structural impact caused by a one-time large adjustment.

[0033] Furthermore, step S200 also includes, after the hanging basket moves, scanning the bottom surface of the cast arch rib by an unmanned aerial vehicle, and matching the point cloud data scanned by the unmanned aerial vehicle with the actual position coordinates and satellite radar data to correct the digital twin model of the arch bridge. Due to the differences between the poured segment and the segment after solidification and forming, the bottom surface of the cast arch rib is actually measured by the unmanned aerial vehicle to dynamically correct the positioning deviation caused by the concrete solidification deformation, thereby eliminating the error of the hanging basket Beidou positioning during the pouring stage, making the model accurately restore the real alignment, making the subsequent adjustment instructions more in line with the actual structure, and preventing the alignment deviation accumulated due to shrinkage deformation from the source to ensure the alignment of the arch bridge.

[0034] Furthermore, the hanging basket is provided with an inclination sensor and a displacement meter. In step S200, the hanging basket inclination data and the hanging basket displacement data are also acquired. The adjustment instruction in step S600 includes the hanging basket inclination adjustment data and the displacement adjustment data and is sent to the hanging basket hydraulic system. The hanging basket hydraulic system adjusts the position of the hanging basket according to the inclination adjustment data and the displacement adjustment data. The lower-mounted hanging basket integrates Beidou positioning, inclination, and displacement sensors, fuses the spatial coordinates and attitude data in real time, automatically calculates the deviation between the actual position of the segment and the target, and drives the hydraulic system to adjust the posture synchronously.

[0035] Furthermore, it further includes step S700. Embedded Beidou measuring points are arranged at set intervals along the axis of the arch rib in the already cast segment; after the bridge is completed, the Beidou base station conducts 24-hour static observations on all the Beidou measuring points of the whole bridge, and outputs the linear report of the whole bridge. By embedding Beidou measuring points, there is no need to manually set up total stations point by point for remeasurement. The Beidou receiver automatically collects data at high frequency and uploads it in real time, saving the cumbersome procedures of the traditional "running points - aiming - recording". During the bridge completion acceptance, the system automatically generates a three-dimensional linear report based on the data of the embedded measuring points, which is compressed from the original 3-day manual remeasurement to automatic output within a few hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is the flowchart of the steps of the present invention.

[0037] Figure 2 It is the global adjustment flowchart of Embodiment 1.

[0038] Figure 3 It is the global adjustment flowchart of Embodiment 2.

[0039] Figure 4 It is the schematic diagram of the lower-mounted hanging basket. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The following is further detailed through specific embodiments:

[0041] Embodiment 1 is basically as shown in the Figure 1 、 2 figures: A cantilever casting construction method using a lower-mounted bridge arch ring includes the following steps;

[0042] S100: Set up a Beidou base station on the abutment cap on the bank of the bridge site, and set a fixed Beidou positioning terminal on the top of the completed abutment or pier as a reference point. Establish a three-dimensional coordinate system based on the reference point, and calculate the target position coordinates of each casting segment of the arch bridge according to the three-dimensional coordinate system;

[0043] S200: Install the hanging basket Beidou positioning terminal on the lower-mounted hanging basket. The hanging basket is also equipped with an inclination sensor and a displacement meter. Calculate the actual position coordinates of the current segment to be poured based on the Beidou positioning data, the hanging basket inclination data, and the hanging basket displacement data. And obtain the three-dimensional data of the arch bridge through UAV surveying and mapping. Build a digital twin model of the arch bridge based on the actual position coordinates and the three-dimensional data of the arch bridge. At least two Beidou positioning terminals are arranged, respectively on both sides of the front end of the hanging basket cantilever. Multiple Beidou positioning terminals can be arranged on the hanging basket cantilever according to positioning requirements, and multiple Beidou positioning terminals are arranged at the front end and both sides of the formwork system to monitor the deformation during concrete pouring.

[0044] After the hanging basket moves, scan the bottom surface of the cast arch rib by UAV, and match the UAV scanned point cloud data with the actual position coordinates and satellite radar data to correct the digital twin model of the arch bridge.

[0045] S300: Compare and analyze the actual position coordinates with the target coordinates to obtain difference data. Judge whether the difference data exceeds the first preset difference range. If the difference data is within the first preset difference range, judge whether the current segment meets the global adjustment condition. If not, the current segment is not adjusted. If so, perform global adjustment on the current segment and calculate the adjustment instruction, and execute step S600. If the difference data exceeds the first preset difference range, mark the point where the difference data exceeds the first preset difference range as the point to be adjusted. Global adjustment includes the fixed segment number adjustment method and the dynamic segment adjustment method. In this embodiment, it is the fixed segment adjustment method, and the specific steps are as follows;

[0046] S331: Judge whether the segment type of the current segment n belongs to the segment to be corrected. The segments to be corrected include the main correction segment and the micro-adjustment segment. If it is judged to be yes, calculate the adjustment instruction according to the segment type. If it is judged to be no, when the absolute value of the deviation of the current segment n |Δ n | is greater than the tightening threshold, or the cumulative deviation of the whole bridge |ΔS| is greater than the set deviation threshold, perform global adjustment;

[0047] S332: Mark the current segment n as the reference segment, the n + 1 segment as the main correction segment, and the n + 2 segment as the micro-adjustment segment; then; the formwork correction amount of the n + 1 segment is: C n+1 =-k·Δ n or C n+1 =-k·ΔS; the formwork correction amount of the n + 2 segment is: C n+2 =-(1 - k)·Δ n or C n+2 =-(1 - k)·ΔS; and satisfy the cumulative error of three segments: Δ n +C n+1 +C n+2 =0 or ΔS + C n+1 +Cn+2 = 0.

[0048] The value range of the coefficient k is (0.5, 1), and |C n+1 | ≤ α, where α is the maximum stroke of the hanging basket oil cylinder.

[0049] Taking the coefficient k value of 0.75 and the deviation as the plane deviation as an example; the left deviation of the nth segment is 4 mm, that is, Δ n = +4 mm; the right adjustment of the (n + 1)th segment is C n+1 = -k·Δ n = -0.75 × 4 = -3 mm; the right adjustment of the (n + 2)th segment is C n+2 = -(1 - k)·Δ n = -0.25 × 4 = -1 mm; the total correction of the three segments: 4 - 3 - 1 = 0, and the error is zeroed.

[0050] S400: Statistically analyze the quantity, position, and difference values of the points to be adjusted to generate a difference data set, generate a pre-adjustment instruction according to the difference data set, pre-adjust the digital twin model of the arch bridge according to the pre-adjustment instruction, and generate a pre-adjusted arch bridge model;

[0051] S500: Compare the coordinates of the pre-adjusted arch bridge model with the target position coordinates to obtain pre-adjustment difference data, and determine whether the pre-adjustment difference data exceeds the second preset difference range, and the second preset difference range is smaller than the first preset difference range; if so, mark the difference data that exceeds the second preset difference range as the point to be adjusted, and return to execute step S400, if not, output the pre-adjustment instruction as the adjustment instruction;

[0052] S600: Adjust the hanging basket according to the adjustment instruction;

[0053] S700: Layout embedded Beidou measurement points at regular intervals along the axis of the arch rib in the cast segments; after the bridge is completed, use the Beidou base station to conduct 24-hour static observations on all the Beidou measurement points of the whole bridge, and output the linear report of the whole bridge.

[0054] Example 2 is as Figure 3 shown. The same parts as Example 1 will not be described in detail. The differences are that this example adopts the dynamic segment adjustment method, and the specific steps are as follows;

[0055] S311: Judge that the absolute value of the deviation of the current segment is greater than the tightening threshold, or the cumulative deviation of the whole bridge is greater than the set deviation threshold, then perform global adjustment;

[0056] S312: Establish a dynamic correction model for the whole bridge segment linkage; state vector: X n = [d1, d2,..., d n T ; observation vector: L n ​= [Δ1, Δ2,..., Δ n T ; Error equation: l n = H n ·X n + V n ;

[0057] where Hn is the segment influence matrix, Vn is the observation noise matrix, reflecting the random error characteristics of the observations, and its diagonal is the variance of each component where H ij is calculated by the following formula;

[0058]

[0059] V n reflects the random error characteristics of the observations, and its diagonal is the variance of each component V n is calculated in the following way. According to the nominal accuracy of the Beidou positioning terminal instrument, a diagonal matrix V n ,

[0060]

[0061] Using the adjustment residual V of the previous segment n-1 to recursively calculate the current noise:

[0062]

[0063] where β = 0.8 is the forgetting factor. When the hanging basket moves to a new segment, if the satellite geometric configuration difference PDOP > 6, automatically multiply σ by a deterioration factor of 1.5 times.

[0064] S313: Calculate the least squares solution;

[0065]

[0066] d i is the single-segment correction amount; w ik is the weight coefficient, decaying with the segment distance; the single-segment correction amount |d i | ≤ α, where α is the maximum stroke of the hanging basket cylinder; if it exceeds the limit, it will be corrected in multiple rounds, specifically;

[0067] The correction value for this round is: The remaining correction value is:

[0068] S314: When adding the (n + 1)-th segment, update X using the recursive least squares method n+1 , and the formula is as follows;

[0069] X n+1 = X​n -K n+1 (H n+1 ·X n -Δ n+1 )

[0070] where K n+1 is a gain matrix, adaptively adjusted according to the accuracy of new measurement points, reducing the computational load by 90%.

[0071] Adopt a dynamic global adjustment scheme with unlimited number of segments, introduce the least squares method, use the coordinate deviations of all measurement points on the whole bridge as observation values, establish error equations, and solve the correction amounts of each segment; use recursive least squares to gradually update the correction amounts instead of recalculating the whole bridge every time, reducing the computational load and having a fast response speed, meeting the fast response requirements of on-site construction; through the state space model + recursive least squares, it realizes that for each newly added segment, the correction amounts of the whole bridge are automatically updated without waiting for a fixed number of segments. The deviation of a single segment can trigger global adjustment, and the influence weights between segments are considered, for example, the deviation at the proximal end has a greater impact, avoiding "over-adjustment at the distal end" in correction.

[0072] The above are only embodiments of the present invention, and common knowledge such as specific structures and characteristics known in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application should be subject to the content of its claims, and the specific implementation manners described in the specification can be used to explain the content of the claims.

Claims

1. A suspended pouring construction method using a bottom-mounted bridge arch ring, characterized in that: The steps include: S100: A Beidou base station is set up on the bridge site shore foundation, and a fixed Beidou positioning terminal is set up on the top of the completed abutment or pier as a reference point. A three-dimensional coordinate system is established based on the reference point, and the target position coordinates of each casting section of the arch bridge are calculated based on the three-dimensional coordinate system; S200: Install the Beidou positioning terminal on the lower hanging basket to obtain the actual position coordinates of the current segment to be cast; obtain the three-dimensional data of the arch bridge through drone mapping, and build a digital twin model of the arch bridge based on the actual position coordinates and the three-dimensional data of the arch bridge; S3 00: Compare and analyze the actual position coordinates with the target coordinates to obtain difference data, and determine whether the difference data exceeds the first preset difference range. If not, determine whether the current segment meets the global adjustment conditions. If so, perform global adjustment on the current segment and calculate the adjustment instruction, and execute step S600; if so, mark the difference data as a point to be adjusted when it exceeds the first preset difference range; S400: Statistically analyzing the number, position and difference value of the difference points to be adjusted to generate a difference data set, generating a pre-adjustment instruction according to the difference data set, pre-adjusting the digital twin model of the arch bridge according to the pre-adjustment instruction, and generating a pre-adjusted arch bridge model; S5 00: Compare the pre-adjusted arch bridge model coordinates with the target position coordinates to obtain pre-adjusted difference data, and determine whether the pre-adjusted difference data exceeds a second preset difference range, and the second preset difference range is smaller than the first preset difference range; If yes, the difference data exceeding the second preset difference range is marked as a difference point to be adjusted, and the process returns to step S400; if no, the pre-adjustment instruction is output as an adjustment instruction; S600: Adjust the hanging basket according to the adjustment instruction.

2. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 1 is characterized in that: The specific steps of global adjustment in step S300 are as follows: S301: Determine whether the segment type of the current segment n belongs to the segment to be corrected. The segment to be corrected includes the main correction segment and the fine adjustment segment. If it is judged to be yes, the adjustment instruction is calculated according to the segment type; if it is judged to be no, the absolute value of the deviation of the current segment n |Δ n When | is greater than the tightening threshold, or the total bridge deviation |ΔS| is greater than the set deviation threshold, a global adjustment is performed; S302: Mark the current segment n as the reference segment, the n+1 segment as the main correction segment, and the n+2 segment as the fine adjustment segment; then; the mold correction amount of the n+1 segment is: C n+1 =-k·Δ n or C n+1 =-k·ΔS; the correction amount of the mold erection of the n+2th segment is: C n+2 =-(1-k)·Δ n or C n+2 =-(1-k)·ΔS; and satisfy the three-segment cumulative error: Δ n +C n+1 +C n+2 =0 or ΔS+C n+1 +C n+2 =0.

3. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 1 is characterized in that: The specific steps of global adjustment in step S300 are as follows: S311: If it is determined that the absolute value of the current segment deviation is greater than the tightening threshold, or the total deviation of the entire bridge is greater than the set deviation threshold, a global adjustment is performed; S312: Establish a dynamic correction model for the linkage of all bridge segments; state vector: X n =[d1,d2,...,d n ] T ; Observation vector: L n =[Δ1,Δ2,...,Δ n ] T ; Error equation: l n =H n X n +V n ; Among them, Hn is the segment influence matrix, Vn is the observation noise matrix; ij Calculated by the following formula; S313: Calculate the least squares solution; d i is the correction value of a single segment; w ik is the weight coefficient, which decays with segment distance; S314: When adding the n+1th segment, update X using the recursive least squares method n+1 , the formula is as follows; X n+1 =X n -K n+1 (H n+1 ·X n -Δ n+1 ) Where K n+1 is the gain matrix.

4. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 3 is characterized in that: The single segment correction amount |d i |≤α, α is the maximum stroke of the basket cylinder; if it exceeds the limit, it will be corrected in multiple rounds.

5. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 1 is characterized in that: The step S200 also includes scanning the bottom surface of the cast arch rib by a drone after the hanging basket moves, and matching the drone scanning point cloud data with the actual position coordinates and Beidou satellite data to correct the digital twin model of the arch bridge.

6. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 1 is characterized in that: The hanging basket is provided with an inclination sensor and a displacement meter, and the step S200 is also used to obtain the hanging basket inclination data and the hanging basket displacement data. The adjustment instruction of the step S600 includes the hanging basket inclination adjustment data and the displacement adjustment data and is sent to the hanging basket hydraulic system. The hanging basket hydraulic system adjusts the hanging basket position according to the inclination adjustment data and the displacement adjustment data.

7. The suspended pouring construction method using a bottom-mounted bridge arch ring according to claim 1 is characterized in that: It also includes step S700, laying out embedded Beidou measuring points at set intervals along the arch rib axis in the cast segments; after the bridge is completed, using the Beidou base station to conduct 24-hour static observation of the Beidou measuring points of the entire bridge and output a full-bridge linear report.

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