Dynamic pre-camber regulation method and system in pouring process of u-shaped simply supported aqueduct

Abstract

The application discloses a U-shaped simply-supported aqueduct pouring process pre-camber dynamic regulation method and system, relates to the technical field of hydraulic engineering construction, and comprises the following steps: collecting longitudinal settlement, transverse eccentric load, structure stress and temperature and humidity data in real time through a multi-source sensing module; constructing a wet weight-settlement coupling model based on the transverse eccentric load and structure stress data, calculating the concrete wet weight in real time; calculating the load eccentricity through the transverse eccentric load data to correct the influence of support torsional deformation on settlement; fusing the longitudinal settlement data by using an extended Kalman filter to generate a pre-camber dynamic compensation amount; when the compensation amount exceeds a preset threshold, triggering a fuzzy PID controller to adjust the hydraulic jacking amount of a hydraulic servo jacking mechanism, and monitoring the initial setting state of the concrete at the same time; after the concrete pouring is completed, switching the electromagnetic valve to release the hydraulic oil circuit, and pushing the piston rod to the initial position through a self-resetting execution unit. The construction precision and safety of the U-shaped aqueduct are ensured.

Description

Technical Field

[0001] This invention relates to the field of water conservancy engineering construction technology, and in particular to a method and system for dynamic control of pre-camber during the pouring of a U-shaped simply supported aqueduct. Background Technology

[0002] U-shaped simply supported aqueducts are an important type of hydraulic water conveyance structure, widely used in irrigation, water diversion, and inter-basin water transfer projects. Their construction often employs a cast-in-place process using a support structure, requiring a pre-set mid-span camber to compensate for deflection caused by support settlement and the self-weight of the concrete during pouring.

[0003] Traditional pre-camber setting mainly relies on geological survey data and empirical formulas for static prediction. However, under complex geological conditions, the support foundation is prone to uneven settlement, which causes the actual alignment to deviate significantly from the design value, and the deviation can reach ±20mm.

[0004] Furthermore, the semi-open structural characteristics of the U-shaped cross-section make it prone to lateral eccentric loading during concrete pouring, leading to stress concentration in the structure. Existing monitoring methods cannot effectively capture such multidimensional dynamic changes, which are manifested in the following ways:

[0005] 1. Limited monitoring dimensions: Traditional methods typically use total stations to periodically measure the mid-span elevation or place pressure sensors at the bottom of the support, which can only obtain vertical settlement or total weight data, and cannot perceive the lateral load distribution of the U-shaped section and its impact on the torsional deformation of the support in real time.

[0006] 2. Significant compensation lag: Manual adjustment relies on periodic measurements with intervals of ≥30 minutes, making it difficult to match the critical time window for the initial setting of concrete. The adjustment delay leads to compensation failure.

[0007] 3. Insufficient reset capability: Conventional hydraulic jacking systems require manual locking after adjustment and cannot automatically reset to the initial state after pouring, affecting the efficiency of repeated use of the support and having low reset accuracy.

[0008] Therefore, it is crucial to study a dynamic control method for the pre-camber during the pouring of a U-shaped simply supported aqueduct in order to ensure the construction accuracy and safety of the U-shaped aqueduct. Summary of the Invention

[0009] In a first aspect, to solve the above-mentioned technical problems, this invention provides a method for dynamically controlling the pre-camber during the casting of a U-shaped simply supported aqueduct, the method comprising:

[0010] The longitudinal settlement, lateral eccentric load, structural stress and temperature and humidity data of the U-shaped simply supported aqueduct are collected in real time by a multi-source sensing module and the data is preprocessed.

[0011] Based on the lateral eccentric load and the structural stress data, a wet weight-settlement coupled model is constructed to calculate the wet weight of concrete in real time; and the load eccentricity is calculated through the lateral eccentric load data to correct the influence of the torsional deformation of the support on the settlement.

[0012] The longitudinal settlement data is fused using an extended Kalman filter to generate a dynamic compensation amount for the pre-camber. When the compensation amount exceeds a preset threshold, a fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism, while monitoring the initial setting state of the concrete.

[0013] After the concrete pouring is completed, the solenoid valve is switched to release the hydraulic oil circuit, and the piston rod is pushed back to the initial position by the self-resetting execution unit of the hydraulic servo lifting mechanism.

[0014] Furthermore, the multi-source sensing module includes:

[0015] An array of spring-loaded wire displacement devices symmetrically arranged along the longitudinal axis of the U-shaped channel is used to monitor the longitudinal settlement.

[0016] A pressure cell matrix is ​​set laterally in the bottom formwork of the hanging basket to obtain the lateral eccentric load distribution of the cross section;

[0017] Vibrating wire strain gauges or resistance strain gauges are arranged at the mid-span of the main truss to measure the stress of the structure;

[0018] A temperature and humidity sensor is used to acquire the temperature and humidity data, which is used to assist in monitoring the initial setting state of the concrete.

[0019] Furthermore, the method for fusing the collected data by the multi-source sensing module includes:

[0020] Develop a dual-channel acquisition system: a high-frequency channel for acquiring vibration signals and a low-frequency channel for acquiring longitudinal settlement and structural stress data;

[0021] Establish a spatiotemporal alignment mechanism: Use the PTP protocol to achieve time synchronization of multiple sensors, and unify the spatial coordinates to the construction coordinate system.

[0022] Furthermore, the data preprocessing specifically includes:

[0023] The vibration signal is denoised using wavelet packet transform, retaining the effective frequency band of 2-80Hz to ensure the accuracy of the longitudinal settlement measurement;

[0024] Kalman smoothing filter is applied to the lateral off-center load data to suppress hydraulic pulsation interference;

[0025] Temperature compensation is performed on the structural stress data. ,in, For the collected structural stress data, The temperature sensitivity coefficient of the FBG strain gauge; Data was obtained from distributed resistance temperature measurement.

[0026] Furthermore, the wet weight-settlement coupling model satisfies the expression:

[0027]

[0028] In the formula, Real-time wet weight; For the first The strain value of the vibrating wire strain gauge or the resistance strain gauge; This refers to the elastic modulus of the corresponding component; This refers to the pressure cell matrix data; , The calibration coefficients are used and updated online using the recursive least squares method.

[0029] Furthermore, the torsional deformation of the corrected support satisfies the expression:

[0030]

[0031] In the formula, The load eccentricity ,in, Number the pressure cells from 1 to m; The pressure values ​​measured by the pressure cells are numbered from 1 to m. This represents the deformation value at the corresponding position where the force direction is consistent with the force direction. It is the linear torsional stiffness coefficient; It is the nonlinear torsional stiffness coefficient.

[0032] Furthermore, the compensation amount satisfies the expression:

[0033]

[0034] In the formula, This is the observation matrix, which contains geological subsidence rate parameters; This refers to the theoretical precamber value given based on the design precamber curve; This is the Kalman gain weighting factor, used to balance the reliability of the design pre-camber and the measured settlement data. When the observation noise is low, Larger, more dependent on observational data When the model predicts low noise, Smaller, more dependent on design values ; For at any time Actual observed settlement data.

[0035] Furthermore, when the compensation amount exceeds a preset threshold, a fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism, and its control logic satisfies the expression:

[0036]

[0037] In the formula, , , These are the proportional coefficient, integral coefficient, and differential coefficient, respectively, and are determined through optimization using a genetic algorithm. The difference between the desired pre-camber and the actual pre-camber. ,in, It is the target pre-camber based on the design or after correction by extended Kalman filter. It is the actual pre-camber measured in real time by sensors. The output of the controller indicates the real-time lifting amount that the hydraulic servo lifting mechanism needs to apply, which is used to dynamically adjust the height of the template or support structure and compensate for the pre-camber deviation caused by settlement.

[0038] Furthermore, the self-resetting execution unit includes a plurality of disc springs arranged in parallel, wherein:

[0039] During the pouring stage, hydraulic oil pushes the piston rod to rise, and the spring assembly is compressed to store energy;

[0040] During the reset phase, the solenoid valve switches the oil circuit, the spring assembly releases energy to push the piston rod to reset, and after the piston rod resets to the initial position, the reset position of the piston rod is verified by a laser rangefinder in a closed loop.

[0041] A second aspect of the present invention provides a dynamic control system for the pre-camber during the casting process of a U-shaped simply supported aqueduct to implement the method, comprising:

[0042] The multi-source sensing module includes an array of spring-drawn wire displacement devices arranged along the longitudinal axis of the U-shaped channel, a matrix of pressure cells set laterally in the bottom formwork of the hanging basket, vibrating wire strain gauges or resistance strain gauges arranged in the middle of the main truss span, and temperature and humidity sensors, which respectively collect longitudinal settlement, lateral eccentric load, structural stress data and temperature and humidity data in real time during the pouring of the U-shaped simply supported aqueduct.

[0043] The compensation decision module is configured to execute the wet weight-settlement coupling model and the precamber dynamic compensation algorithm.

[0044] The reset execution module includes a hydraulic servo lifting mechanism equipped with a self-resetting execution unit. The hydraulic servo lifting mechanism is based on extended Kalman filtering to fuse settlement data with the design pre-camber curve, and outputs the lifting amount through a fuzzy PID controller. The self-resetting execution unit releases stored energy through a disc spring assembly to achieve reset after the pouring is completed.

[0045] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0046] This invention uses a multi-source sensing module to collect longitudinal settlement, lateral eccentric load, and structural stress data in real time, and combines this with a wet weight-settlement coupling model to dynamically calculate the wet weight distribution of concrete, significantly improving the accuracy and response speed of pre-camber control. The invention employs a control algorithm that integrates extended Kalman filtering and a fuzzy PID controller, which can complete compensation calculation and hydraulic jacking adjustment within 60 seconds, effectively overcoming the lag of traditional manual adjustments and providing an efficient, safe, and intelligent solution for aqueduct engineering under complex geological conditions. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is an overall flowchart of the present invention; Detailed Implementation

[0049] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] This invention aims to provide a method for dynamically controlling the pre-camber during the pouring of a U-shaped simply supported aqueduct, to ensure the construction accuracy and safety of the aqueduct. Please refer to [link / reference]. Figure 1 It mainly includes the following steps:

[0051] S1. The longitudinal settlement, lateral eccentric load, structural stress and temperature and humidity data of the U-shaped simply supported aqueduct are collected in real time through the multi-source sensing module, and the data is preprocessed.

[0052] In a specific example, the arrangement of sensors and data preprocessing in the multi-source sensing module are described below:

[0053] Regarding longitudinal settlement monitoring: A spring-loaded wire displacement sensor array is symmetrically deployed along the longitudinal axis of the U-shaped channel. In this embodiment, 12 sets are deployed, with a spacing of 0.5m in the mid-span area and 1m on both sides. The sensors are installed at the connection points between the hanging basket support beam and the foundation support. The data acquisition frequency is 1Hz during the normal phase and automatically increases to 20Hz during the initial setting stage of the concrete. The data is transmitted to the edge computing gateway via an RS485 bus.

[0054] Regarding lateral eccentric load monitoring: A 3×5 pressure cell matrix is ​​evenly distributed laterally on the bottom formwork of the hanging basket, with a row spacing of 0.8m and a column spacing of 1.2m, directly embedded in the bottom steel structure of the formwork. The lateral scanning frequency is 5Hz / point, and the longitudinal section scanning frequency is 1Hz; the data is transmitted wirelessly via LoRa.

[0055] Regarding structural stress monitoring: Six sets of vibrating wire strain gauges or resistance strain gauges are arranged at the mid-span of the main truss, and two sets of vibrating wire strain gauges or resistance strain gauges are arranged at each anchor point of the hanger. Preferably, the vibrating wire strain gauges or resistance strain gauges are fixed to the steel structure surface using epoxy resin adhesive. The normal frequency for data acquisition is 50Hz, and the frequency is increased to 200Hz when abnormal vibration occurs.

[0056] Regarding temperature and humidity data monitoring: The temperature and humidity sensor in this embodiment is model SHT35, which is placed on the concrete pouring surface and key nodes of the support to monitor the initial setting state of the concrete. The data acquisition frequency is 0.2Hz.

[0057] Before pouring, under no-load conditions, the spring wire displacement device and pressure box are zero-point calibrated, and a standard displacement of 5-10mm is applied to verify their linearity.

[0058] In this embodiment, a multi-mode adaptive acquisition strategy is adopted, and the acquisition frequency is adjusted based on two factors: the pouring stage and the settlement rate, as shown in Table 1 below:

[0059] Table 1

[0060]

[0061] The methods for fusing and collecting data using multi-source sensing modules include:

[0062] 1) Deploy industrial-grade gateways: integrate RS485, LoRa, and fiber optic interfaces to achieve multi-protocol data aggregation;

[0063] 2) Develop a dual-channel acquisition system: the high-frequency channel is used to acquire vibration signals, and the low-frequency channel is used to acquire longitudinal settlement and structural stress data;

[0064] 3) Establish a spatiotemporal alignment mechanism: Use the IEEE 1588PTP protocol to achieve time synchronization of multiple sensors and unify spatial coordinates to the construction coordinate system.

[0065] The preprocessing of multi-source data specifically includes:

[0066] a. The vibration signal is denoised using db4 wavelet packet transform and decomposed to the 6th layer, retaining the effective frequency band of 2-80Hz to ensure the accuracy of longitudinal settlement measurement.

[0067] b. Apply Kalman smoothing filter to the lateral offset data , This is the smoothed pressure value at the current moment; This represents the original pressure value at the current moment. The smoothed value from the previous time step; smoothing factor. Using an empirical value of 0.7, hydraulic pulsation interference is suppressed, resulting in a smooth output pressure value. .

[0068] c. Perform temperature compensation on structural stress data ,in, For the collected structural stress data, The temperature sensitivity coefficient of the FBG strain gauge; Acquired from distributed fiber optic temperature measurement data.

[0069] S2. Based on the lateral eccentric load and structural stress data, a wet weight-settlement coupled model is constructed to calculate the wet weight of concrete in real time; and the load eccentricity is calculated through the lateral eccentric load data to correct the influence of the torsional deformation of the support on the settlement.

[0070] S21. The wet weight-settlement coupling model satisfies the following expression:

[0071]

[0072] In the formula, Real-time wet weight; For the first The strain value of a vibrating wire strain gauge or a resistance strain gauge; To correspond to the elastic modulus of the component, steel 210 GPa; The data is from the pressure cell matrix, and the integration interval covers the current pouring area. , The calibration coefficients are used and updated online using the recursive least squares method, where the forgetting factor is... The value is 0.98, and the update cycle is 10 minutes.

[0073] S22. Lateral eccentric load correction, the eccentricity calculation satisfies the expression:

[0074]

[0075] In the formula, Number the pressure cells from 1 to m; The pressure values ​​measured by the pressure cells are numbered from 1 to m. This represents the deformation value at the corresponding location, which is aligned with the direction of the force.

[0076] The torsional deformation transfer function is:

[0077]

[0078] The linear torsional stiffness coefficient reflects the support's response to load eccentricity. The proportion of linear torsional deformation produced under action; This is a nonlinear torsional stiffness coefficient, reflecting the proportion of higher-order torsional deformation caused by structural geometric nonlinearity or material nonlinearity under large eccentric loads; the coefficient... , Obtained through finite element calibration.

[0079] S3. The longitudinal settlement data is fused using extended Kalman filtering to generate a dynamic compensation amount for pre-camber. When the compensation amount exceeds the preset threshold, the fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism, while monitoring the initial setting state of the concrete.

[0080] In a further embodiment, the state equation for extended Kalman filter (EKF) fusion is:

[0081]

[0082] In the formula, For a moment The pre-camber value; Settlement rate; The sampling time interval; This is process noise.

[0083] The observation equation is:

[0084]

[0085] In the formula, The matrix contains geological settlement rate parameters (e.g., 0.5 mm / min for soft soil foundations).

[0086] Based on Kalman gain update, the output compensation amount satisfies the expression:

[0087]

[0088] In the formula, This is the observation matrix, which contains geological subsidence rate parameters; This refers to the theoretical precamber value given based on the design precamber curve; This is the Kalman gain weighting factor, used to balance the reliability of the design pre-camber and the measured settlement data. When the observation noise is low (data is reliable), Larger, more dependent on observational data When the model predicts low noise (the design curve is reliable), Smaller, more dependent on design values ; For at any time Actual observed settlement data (measured values).

[0089] When the compensation amount exceeds the preset threshold, the fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism. Its control logic satisfies the expression:

[0090]

[0091] In the formula, , , These are the proportional coefficient, integral coefficient, and differential coefficient, respectively, and are determined through optimization using a genetic algorithm. The difference between the desired pre-camber and the actual pre-camber. ,in, It is the target pre-camber based on the design or after correction by extended Kalman filter. It is the actual pre-camber measured in real time by sensors (such as laser rangefinders and inclinometers). The output of the controller indicates the real-time lifting amount (such as the displacement or pressure of the hydraulic cylinder) that the hydraulic servo lifting mechanism needs to apply, which is used to dynamically adjust the height of the template or support structure and compensate for the pre-camber deviation caused by settlement.

[0092] In this embodiment, when the compensation amount exceeds 3mm, the hydraulic servo lifting mechanism is activated, and the lifting speed is adjusted according to the output value of the fuzzy PID controller.

[0093] S4. After the concrete pouring is completed, switch the solenoid valve to release the hydraulic oil circuit, and push the piston rod to reset to the initial position through the self-resetting execution unit set by the hydraulic servo lifting mechanism.

[0094] In this embodiment, the hydraulic servo lifting mechanism adopts a double-acting hydraulic cylinder with an oil elastic modulus of 1700MPa and a maximum lifting speed of 5mm / s.

[0095] The self-resetting actuator comprises several parallel-connected disc springs with a preload of 200 kN and an energy storage capacity of 20.8 kJ. During the pouring stage, hydraulic oil pushes the piston rod upward, compressing the spring assembly to store energy. During the reset stage, the solenoid valve switches the oil circuit, the spring assembly releases energy to push the piston rod back to its initial position, and the reset position of the piston rod is verified by a laser rangefinder in a closed-loop manner.

[0096] After the pouring is completed, the reset action is performed. The solenoid valve is manually triggered to switch the oil circuit. The spring assembly completes the reset within 30 seconds. The position error of the laser ranging is ≤0.5mm.

[0097] In a further embodiment, the accuracy guarantee mechanism for the self-resetting execution unit during reset includes mechanical limit, closed-loop control, and locking mechanism. The mechanical limit includes upper and lower limit retaining rings with a spacing tolerance of ±0.05mm. The closed-loop control uses a laser rangefinder combined with a PID controller for real-time feedback of the piston rod position. The locking mechanism includes a wedge-shaped locking block. After reset, the wedge-shaped locking block is hydraulically driven to lock, and the contact stress is checked to see if it is ≥3MPa. Otherwise, it is manually corrected by adjusting the fine-tuning nut.

[0098] In a further embodiment, a digital twin verification platform is also included, which simulates different working conditions by establishing an ANSYS-ADAMS co-simulation model:

[0099] Condition 1, Uniform Settlement: Verify longitudinal compensation by simulating a foundation settlement rate of 0.5 mm / min and verifying that the linear error is ≤ ±1.5 mm.

[0100] Condition 2, Lateral eccentric load: Verify torsional deformation suppression by applying eccentricity. , For the span, verify the twist angle. ≤0.5°.

[0101] Operating Condition 3, Sudden Vibration: To verify the filter's effectiveness, white noise (SNR=20dB) was injected and a 50Hz sinusoidal sweep was performed to verify that the filter attenuation was ≥30dB.

[0102] A 30m span U-shaped aqueduct was selected for comparative testing. The traditional group underwent manual adjustment with a measurement interval of 30 minutes; the group in this embodiment was automatically controlled with a sampling interval of 10 seconds. The key indicators are compared in Table 2 below.

[0103] Table 2

[0104]

[0105] This invention also protects a dynamic control system for pre-camber during the casting process of a U-shaped simply supported aqueduct using the above method, including a multi-source sensing module, a compensation decision module, and a reset execution module.

[0106] The multi-source sensing module includes an array of spring-loaded wire displacement devices arranged along the longitudinal axis of the U-shaped channel, a matrix of pressure cells set laterally on the bottom formwork of the hanging basket, vibrating wire strain gauges or resistance strain gauges arranged in the middle of the main truss span, and temperature and humidity sensors, which respectively collect longitudinal settlement, lateral eccentric load, structural stress data and temperature and humidity data in real time during the pouring of the U-shaped simply supported aqueduct.

[0107] The compensation decision module is configured to execute the wet weight-settlement coupling model and the precamber dynamic compensation algorithm.

[0108] The reset execution module includes a hydraulic servo lifting mechanism equipped with a self-resetting execution unit. The hydraulic servo lifting mechanism is based on extended Kalman filtering to fuse settlement data with the design pre-camber curve, and outputs the lifting amount through a fuzzy PID controller. The self-resetting execution unit releases stored energy through a disc spring assembly to achieve reset after the pouring is completed.

[0109] In this embodiment, the pressure box matrix is ​​integrated with the hydraulic servo lifting mechanism, wherein each pressure box corresponds to a single flat jack. The jack incorporates a laser rangefinder, a solenoid valve, a piston rod, and a wedge-shaped locking block, and controls the oil circuit switching via the solenoid valve to drive the piston rod to lift and reset.

[0110] The self-resetting actuator includes several disc springs arranged in parallel, located between the piston rod and the cylinder flange of the main hydraulic cylinder. After the self-resetting actuator is reset to its position, it activates the wedge locking block to lock, and the locking is verified through a closed-loop test using a laser rangefinder.

[0111] This invention achieves three-dimensional synchronous sensing of longitudinal settlement, lateral eccentric load, and structural stress for the first time. By integrating extended Kalman filtering and fuzzy PID control, it achieves a compensation response time of less than 60 seconds, which is faster than the initial setting time of concrete. At the same time, it utilizes energy storage during the pouring process to achieve zero-energy reset, with a reset accuracy of ±0.5mm.

[0112] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for dynamically controlling the pre-camber during the casting of a U-shaped simply supported aqueduct, characterized in that, The method includes: The longitudinal settlement, lateral eccentric load, structural stress and temperature and humidity data of the U-shaped simply supported aqueduct are collected in real time by a multi-source sensing module and the data is preprocessed. Based on the lateral eccentric load and the structural stress data, a wet weight-settlement coupled model is constructed to calculate the wet weight of concrete in real time; and the load eccentricity is calculated through the lateral eccentric load data to correct the influence of the torsional deformation of the support on the settlement. The longitudinal settlement data is fused using an extended Kalman filter to generate a dynamic compensation amount for the pre-camber. When the compensation amount exceeds a preset threshold, a fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism, while monitoring the initial setting state of the concrete. After the concrete pouring is completed, the solenoid valve is switched to release the hydraulic oil circuit, and the piston rod is pushed back to the initial position by the self-resetting execution unit of the hydraulic servo lifting mechanism.

2. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1, characterized in that, The multi-source sensing module includes: An array of spring-loaded wire displacement devices symmetrically arranged along the longitudinal axis of the U-shaped channel is used to monitor the longitudinal settlement. A pressure cell matrix is ​​set laterally in the bottom formwork of the hanging basket to obtain the lateral eccentric load distribution of the cross section; Vibrating wire strain gauges or resistance strain gauges are arranged at the mid-span of the main truss to measure the stress of the structure; A temperature and humidity sensor is used to acquire the temperature and humidity data, which is used to assist in monitoring the initial setting state of the concrete.

3. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1, characterized in that, The method for fusing and collecting data by the multi-source sensing module includes: Develop a dual-channel acquisition system: a high-frequency channel for acquiring vibration signals and a low-frequency channel for acquiring longitudinal settlement and structural stress data; Establish a spatiotemporal alignment mechanism: Use the PTP protocol to achieve time synchronization of multiple sensors, and unify the spatial coordinates to the construction coordinate system.

4. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 3, characterized in that, The data preprocessing specifically includes: The vibration signal is denoised using wavelet packet transform, retaining the effective frequency band of 2-80Hz to ensure the accuracy of the longitudinal settlement measurement; Kalman smoothing filter is applied to the lateral off-center load data to suppress hydraulic pulsation interference; Temperature compensation is performed on the structural stress data. ,in, For the collected structural stress data, The temperature sensitivity coefficient of the FBG strain gauge; Data was obtained from distributed resistance temperature measurement.

5. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 2, characterized in that, The wet weight-settlement coupling model satisfies the following expression: In the formula, Real-time wet weight; For the first The strain value of the vibrating wire strain gauge or the resistance strain gauge; This refers to the elastic modulus of the corresponding component; This refers to the pressure cell matrix data; , The calibration coefficients are used and updated online using the recursive least squares method.

6. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1 or 5, characterized in that, The torsional deformation of the corrected support satisfies the expression: In the formula, The load eccentricity ,in, Number the pressure cells from 1 to m; The pressure values ​​measured by the pressure cells are numbered from 1 to m. This represents the deformation value at the corresponding position where the force direction is consistent with the force direction. It is the linear torsional stiffness coefficient; It is the nonlinear torsional stiffness coefficient.

7. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1, characterized in that, The compensation amount satisfies the expression: In the formula, This is the observation matrix, which contains geological subsidence rate parameters; This refers to the theoretical precamber value given based on the design precamber curve; This is the Kalman gain weighting factor, used to balance the reliability of the design pre-camber and the measured settlement data. When the observation noise is low, Larger, more dependent on observational data When the model predicts low noise, Smaller, more dependent on design values ; For at any time Actual observed settlement data.

8. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1 or 7, characterized in that, When the compensation amount exceeds a preset threshold, a fuzzy PID controller is triggered to adjust the hydraulic lifting amount of the hydraulic servo lifting mechanism. Its control logic satisfies the expression: In the formula, , , These are the proportional coefficient, integral coefficient, and differential coefficient, respectively, and are determined through optimization using a genetic algorithm. The difference between the desired pre-camber and the actual pre-camber. ,in, It is the target pre-camber based on the design or after correction by extended Kalman filter. It is the actual pre-camber measured in real time by sensors. The output of the controller indicates the real-time lifting amount that the hydraulic servo lifting mechanism needs to apply, which is used to dynamically adjust the height of the template or support structure and compensate for the pre-camber deviation caused by settlement.

9. The method for dynamic control of pre-camber during the casting process of a U-shaped simply supported aqueduct according to claim 1, characterized in that, The self-resetting actuator includes several disc springs arranged in parallel, wherein: During the pouring stage, hydraulic oil pushes the piston rod to rise, and the spring assembly is compressed to store energy; During the reset phase, the solenoid valve switches the oil circuit, the spring assembly releases energy to push the piston rod to reset, and after the piston rod resets to the initial position, the reset position of the piston rod is verified by a laser rangefinder in a closed loop.

10. A dynamic control system for pre-camber during the casting process of a U-shaped simply supported aqueduct, implementing the method as described in any one of claims 1-9, characterized in that, include: The multi-source sensing module includes an array of spring-drawn wire displacement devices arranged along the longitudinal axis of the U-shaped channel, a matrix of pressure boxes set laterally in the bottom formwork of the hanging basket, vibrating wire strain gauges or resistance strain gauges arranged in the middle of the main truss span, and temperature and humidity sensors, which respectively collect longitudinal settlement, lateral eccentric load, structural stress data and temperature and humidity data in real time during the pouring of the U-shaped simply supported aqueduct. The compensation decision module is configured to execute the wet weight-settlement coupling model and the precamber dynamic compensation algorithm; The reset execution module includes a hydraulic servo lifting mechanism equipped with a self-resetting execution unit. The hydraulic servo lifting mechanism is based on extended Kalman filtering to fuse settlement data with the design pre-camber curve, and outputs the lifting amount through a fuzzy PID controller. The self-resetting execution unit releases stored energy through a disc spring assembly to achieve reset after the pouring is completed.

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