Intelligent monitoring system and method for whole construction process of large-span steel box tied arch bridge

Abstract

The invention discloses an intelligent monitoring system and method for the whole construction process of a large-span steel box tied arch bridge. According to the system and the method, aiming at key technical problems in integral incremental launching construction, real-time monitoring, accurate analysis and dynamic control of structure line shape, stress, temporary structure stress and multi-point synchronism in the incremental launching process are realized by integrating sensing monitoring, data acquisition, an incremental launching construction finite element model as shown in figure 4 and a feedback control module. Graded early warning and control logic (as shown in Figure 5) in the incremental launching process is particularly constructed, the industrial pain points that wide bridge incremental launching is asynchronous, prone to deviation and high in safety risk are effectively solved, and the automation level, the intelligence level and the safety of incremental launching construction are remarkably improved.

Description

Technical fields:

[0001] This invention belongs to the field of construction monitoring technology in bridge engineering, and specifically relates to a full-process, multi-parameter intelligent monitoring system and method for large-span steel box girder arch bridges under complex construction processes (such as overall jacking). Background technology:

[0002] Long-span steel box girder arch bridges are increasingly widely used in transportation engineering due to their advantages such as lightweight structure, beautiful shape, and large span capacity. These bridges often employ a construction method of factory manufacturing, on-site assembly, and overall jacking. The construction process is a dynamic process in which the structural system and load state are constantly changing. During this process, the internal forces and alignment of the structure directly affect the quality of the completed bridge and construction safety.

[0003] Currently, traditional construction monitoring methods have the following limitations:

[0004] 1. Data discretization: Independent instruments are usually used to measure parameters such as linearity and stress. There is a lack of linkage analysis between the data, making it difficult to form a comprehensive evaluation of the structural condition.

[0005] 2. Delayed feedback: The processing and analysis of monitoring data often rely on manual labor, which cannot provide real-time guidance for construction. Corrective measures may be delayed, which could lead to the accumulation of errors.

[0006] 3. Insufficient predictability: There is a lack of accurate prediction and early warning in conjunction with the monitoring data of the main structure for key issues such as the stress safety of temporary structures (such as guide beams and temporary supports) during the jacking process and the timing of system transformation.

[0007] 4. Systemic deficiencies: The system has failed to form a closed-loop control system that integrates real-time monitoring, intelligent analysis, dynamic prediction and feedback control, and especially lacks automated control strategies for sensitive factors such as temperature effects and push synchronization.

[0008] Especially during the overall jacking construction process, the superstructure and guide beam alignment are constantly changing, the stress state of the temporary supports is complex, and the main beam not only experiences vertical disturbance but may also twist in the plane, making alignment and synchronization control extremely difficult. Improper monitoring can easily lead to structural alignment deviations, stress exceeding limits, or even safety accidents.

[0009] Therefore, there is an urgent need in this field for a system and method that can achieve full-process, intelligent, and high-precision monitoring to ensure that bridge construction is safe and accurately reaches the designed bridge state. Summary of the Invention:

[0010] The purpose of this invention is to convey the following:

[0011] To address the shortcomings of existing technologies, this invention aims to provide an intelligent monitoring system and method for the entire construction process of a long-span steel box girder arch bridge. The core of this invention is to solve the challenges of structural safety, precise alignment control, and multi-point synchronization in the overall jacking construction, thereby ensuring construction safety and bridge completion accuracy.

[0012] Technical solution of the present invention

[0013] To achieve the above objectives, the present invention adopts the following technical solution:

[0014] In a first aspect, the present invention provides an intelligent monitoring system for the entire construction process of a long-span steel box girder arch bridge, characterized in that the system is particularly suitable for monitoring the overall jacking construction and includes:

[0015] Sensor monitoring module: Used to collect physical parameters at the construction site, including:

[0016] The geometric monitoring unit is equipped with a total station and a precision level, used to measure the three-dimensional coordinates of the control points of the main beam and main arch.

[0017] The stress monitoring unit is equipped with vibrating wire strain gauges and is installed at the arch foot, arch crown section and key stress sections of the main beam.

[0018] The cable force monitoring unit is equipped with a cable force dynamic measuring instrument based on the principle of random environmental vibration, which is used to measure the cable force of the suspender rod;

[0019] The temperature monitoring unit is equipped with a semiconductor temperature sensor for measuring structural temperature and ambient temperature.

[0020] In order to accurately control the jacking process, the geometric monitoring unit performs high-frequency verification of the main beam axis, guide beam alignment and temporary support displacement before and after key jacking conditions; the stress monitoring unit tracks and monitors the stress of key sections of the steel guide beam, temporary steel support and main arch and main beam in real time during the jacking process.

[0021] Data acquisition and transmission module: Communicatively connected to the sensing and monitoring module, used to receive, preliminarily process and wirelessly transmit the physical parameters in real time.

[0022] The calculation, analysis, and simulation module is communicatively connected to the data acquisition and transmission module. It contains a pre-stored simulation model of the entire bridge construction process based on finite element analysis software (such as Midas Civil). This module is used for:

[0023] Based on the received real-time data, simulation calculations are performed during the construction phase to obtain theoretical prediction values;

[0024] The measured values ​​are compared with the theoretical predicted values ​​to perform error analysis, parameter identification, and state assessment.

[0025] Predict the structural behavior in subsequent construction phases.

[0026] The module performs a detailed simulation of the entire jacking process of the arch beam, calculates the internal forces and stress state of the temporary steel supports, the internal forces and deformations of the main arch and main beam, and the internal forces and deformations of the steel guide beam under each key jacking condition; and performs a special analysis of jacking stability, including stability verification of the steel guide beam and temporary steel supports.

[0027] Feedback control and early warning module: Communicatively connected to the calculation, analysis, and simulation module, used for:

[0028] Based on the error analysis results, construction adjustment instructions are generated. These instructions particularly focus on the dynamic correction of pre-camber during the jacking process, the multi-point synchronous adjustment instructions of the walking jacking equipment (including jacking, translation, and lateral correction), and the jacking start and stop decisions based on stress state.

[0029] It includes a three-level early warning mechanism. When the deviation of the monitored parameters exceeds the preset threshold, it will trigger prompts, warnings and alarms in sequence, and generate corresponding handling suggestions.

[0030] Secondly, the present invention provides a construction monitoring method using the above-mentioned system, characterized in that the method takes the monitoring of the jacking process as the core control link, and includes the following steps:

[0031] S1: Preliminary preparation stage: Establish a finite element model for construction control, determine the target state of the completed bridge and the theoretical control target values ​​for each construction stage; complete the deployment and calibration of the sensor monitoring module on site;

[0032] S2: Real-time data acquisition stage: During each key process of bridge construction, including main beam and main arch assembly, overall jacking, system conversion, and bridge deck paving, the aforementioned sensing and monitoring module collects geometric, stress, cable force, and temperature data in real time; in particular, high-frequency data acquisition is carried out in each cycle of the overall jacking.

[0033] S3: Data Analysis and State Identification Stage: The real-time collected data is input into the calculation analysis and simulation module, compared with the theoretical model, design parameter errors are identified, the calculation model is updated, and the safety of the current state of the structure is assessed. This stage focuses on analyzing the error between the actual state and the theoretical state of the structure during the jacking process, and assessing the stress safety of the guide beam, temporary supports, and main structure.

[0034] S4: Feedback Control Stage: Based on the analysis results of step S3, the feedback control and early warning module generates and issues construction control commands to dynamically adjust the alignment, stress, or cable force during construction; the core of this stage includes the dynamic adjustment of the jacking synchronization, jacking trajectory line, and jacking sequence.

[0035] S5: Iterative Cycle Stage: Repeat steps S2 to S4 throughout the entire jacking construction cycle until the bridge construction is completed, ensuring that the completed bridge meets the design requirements.

[0036] Beneficial effects of the present invention

[0037] Compared with the prior art, the present invention has the following significant advantages:

[0038] Systematic: It deeply integrates geometry, stress, cable force, temperature monitoring with finite element simulation analysis to form a complete "monitoring-analysis-feedback" closed-loop control system.

[0039] Real-time performance and predictability: By driving model updates with real-time data, it can not only reflect the current structural status, but also predict the impact of subsequent construction, realizing the transformation from "post-event correction" to "pre-event prediction and control".

[0040] High precision and safety: Control accuracy is significantly improved through parameter identification and model correction. The three-level early warning mechanism can effectively prevent structural overruns and ensure construction safety, making it particularly suitable for high-risk processes such as jacking.

[0041] Automation and intelligence: Reduced manual intervention, improved monitoring efficiency and control response timeliness, and provided core technical support for the digital and intelligent construction of bridges.

[0042] Advantages of the jacking control system: By establishing a simulation model of the entire jacking process and real-time data-driven operation, the system achieves coordinated control and accurate prediction of the cantilever state of the guide beam, the reaction force of temporary supports, and the stress and alignment of the main structure. This effectively solves technical problems such as asynchronous jacking and easy deviation in wide-span bridges, ensuring the safety and accuracy of the jacking construction. Attached image description:

[0043] Figure 1 Diagram of the Overall Jacking Monitoring Technology System for Wide Steel Box Girder

[0044] Figure 2 Schematic diagram of the layout of measuring points for the main beam and main arch.

[0045] Figure 3 Schematic diagram of the arrangement of stress measuring points for the main beam and main arch

[0046] Figure 4 Finite element model of the jacking construction of Tujiaba Bridge

[0047] Figure 5 Multi-point synchronous jacking hierarchical control logic diagram

[0048] Figure 1 shows the overall architecture of the system of the present invention, which focuses on demonstrating the collaborative working relationship of the four major modules of sensing and monitoring, data acquisition, analysis and calculation and feedback control in the jacking construction scenario, and highlights the key monitoring elements in jacking construction, such as the interaction between the walking jacking equipment group, guide beam, temporary support and monitoring data.

[0049] Figure 2 shows the longitudinal and transverse distribution of the observation sections on the main beam and main arch, as well as the location of the transverse measuring points on each section.

[0050] Figure 3 shows the distribution of stress measurement points at key sections such as the main beam, arch foot, and arch crown.

[0051] Figure 4 shows a simulation model of the entire process of the overall jacking construction of the Tujiaba Bridge arch beam, established using general-purpose structural finite element analysis software such as Midas Civil. The model clearly displays components such as the main arch, main beam, steel guide beam, and temporary steel supports, as well as boundary conditions such as nodal elastic supports simulating the jacking process. This model is the core calculation tool for construction stage simulation, error analysis, and state prediction.

[0052] Figure 5 illustrates the judgment logic of a three-level early warning system ("prompt-warning-alarm") based on core monitoring data such as axis deviation, guide beam deflection, temporary support reaction force, and key section stress during the jacking construction, as well as the execution process of corresponding synchronous adjustment and correction measures such as jacking speed adjustment, single-point correction, and system emergency stop. Detailed implementation method:

[0053] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment takes the construction monitoring of the Tujiaba Bridge (a 158m under-deck steel box girder arch bridge with a total bridge deck width of 59.56m) on the Chongqing-Xiangtan Expressway as an application scenario. The construction process of "beams first, then arches, bridge deck assembly, arch rib support method installation, and overall jacking of the arch beams" adopted is highly representative.

[0054] System deployment:

[0055] Geometric monitoring: Considering the ultra-wide bridge deck, 27 observation sections are arranged along the longitudinal direction of the main girder. At each section, five prism measuring points are placed at different locations from the bridge deck centerline (e.g., -13.719m, ±0.85m, +13.645m) to achieve precise control over the overall bridge deck alignment and torsional deformation. Four prism measuring points are placed at each segment joint of the main arch to closely monitor the arch rib installation axis and elevation.

[0056] Stress monitoring: Five cross-sections were selected at the arch foot and crown of the left and right arch sections of the main arch, and vibrating wire surface strain gauges were installed. Three most unfavorable stress sections (such as near the support and mid-span) were selected on the main beam, and vibrating wire embedded strain gauges were installed to monitor stress changes in real time during the jacking and system transformation processes. Stress monitoring units were also deployed on the steel guide beam and temporary steel supports, which were subjected to complex stresses during the jacking process.

[0057] Cable stress monitoring: Cable stress dynamic measuring instruments are equipped for all 46 cable suspenders arranged in a net pattern throughout the bridge. The cable stress is measured after each tensioning and after the bridge is completed to ensure that the error between the cable stress of the completed bridge and the design value is controlled within the allowable range of -9.7% to +9.84%.

[0058] Temperature monitoring: 24-hour temperature monitoring is performed using the temperature sensor built into the strain gauge and an additional ambient temperature sensor to provide a basis for temperature correction of linear measurement data and cable force monitoring results.

[0059] Implementation of the method:

[0060] During the jacking construction stage (in conjunction with) Figure 4 and Figure 5 (This is the core application scenario of the invention): The system adopts a closed-loop control mode of "prediction-monitoring-feedback". Before each round of jacking, based on... Figure 4 The finite element model shown simulates the upcoming jacking sequence, predicting the alignment, stress, and temporary support reactions at each control point of the main beam, main arch, and guide beam, serving as a theoretical benchmark for monitoring. During the jacking process, the system monitors the guide beam deflection, main beam axis (specification requirement ≤10mm), and key section stresses in real time (e.g., the maximum measured stress of the main arch steel structure is -21.13MPa, and the maximum measured stress of the main beam tie beam is 18.3MPa). Load changes are monitored in real time by pressure transmitters installed at each jacking step to determine jacking synchronization. When the finite element model analysis shows abnormal reactions at a temporary support, guide beam stress approaching the warning value, or axis deviation exceeding limits, the system immediately initiates... Figure 5 The system employs a tiered control logic. For example, when the axis deviation reaches 5mm (warning level), the system instructs to adjust the jacking speed of the corresponding stepping jack or activate the lateral correction function; if the stress exceeds the limit or the axis deviation reaches 8mm (alarm level), jacking is immediately suspended until the cause is identified and adjusted before it can continue. In this embodiment, this system ultimately controls the maximum axis deviation of the arch beam after it has been jacked into place to 6mm, and the maximum deviation of the beam end mileage to 9mm, far exceeding the specifications, ensuring the synchronization, safety, and precise positioning of the wide-span bridge jacking process.

[0061] During the system transition phase: Based on the measured alignment after beam placement, the system uses model calculations and analysis to accurately determine the initial tension force of each hanger and the corresponding sequence for removing temporary supports. During tensioning, the system monitors cable forces and main beam alignment changes in real time to ensure a smooth and controllable transition of the force system from temporary supports to hangers.

[0062] During the bridge completion phase: The system performs comprehensive measurements of the entire bridge alignment and cable tension, comparing the final measured data with the designed bridge state. In this embodiment, the maximum deviation of the completed bridge alignment is controlled within the allowable range specified in the standards, the maximum deviation of the main arch rib axis is 11mm (standard ≤ 26mm), the maximum elevation deviation is 45mm (standard ≤ 52mm), and the cable tension error meets the requirement of ±10%. This verifies the effectiveness and accuracy of the system in monitoring the construction of wide-span, long-span steel box girder arch bridges.

Claims

1. An intelligent monitoring system for the entire construction process of a long-span steel box girder arch bridge, characterized in that, The system is specifically optimized for the overall jacking construction process and includes: a sensing and monitoring module for collecting physical parameters at the construction site, including geometric, stress, cable force, and temperature data. During the jacking stage, it focuses on monitoring the main beam axis, guide beam alignment, temporary support displacement, and the stress of key sections of the steel guide beam, temporary steel supports, and main structure; a data acquisition and transmission module, which is communicatively connected to the sensing and monitoring module, for receiving and transmitting the physical parameters; a calculation, analysis, and simulation module, which is communicatively connected to the data acquisition and transmission module and pre-stores a simulation model of the entire bridge construction process. This model is a finite element model of the jacking construction, as shown in Figure 4, including the main arch, main beam, steel guide beam, and temporary steel supports, used for jacking construction stage simulation, error analysis, stability assessment, and state prediction; and a feedback control and early warning module, which is communicatively connected to the calculation, analysis, and simulation module, for generating jacking synchronization adjustment, correction, and safety decision commands based on the analysis results and triggering early warnings.

2. The system according to claim 1, characterized in that, The sensing and monitoring module includes: a geometric monitoring unit equipped with a total station and a precision level for measuring the three-dimensional coordinates of the control points of the main beam and main arch; a stress monitoring unit equipped with vibrating wire strain gauges, which are installed on the steel guide beam, temporary steel supports, and key sections of the main arch and main beam that are subject to complex stresses during the jacking process; a cable force monitoring unit equipped with a cable force dynamic measuring instrument for measuring the cable force of the suspenders; and a temperature monitoring unit equipped with a temperature sensor for measuring the structural temperature and ambient temperature.

3. The system according to claim 1, characterized in that, The calculation, analysis and simulation module performs specific calculations and analyses on the strength, stiffness and stability of the steel guide beam and temporary steel support during the jacking process.

4. The system according to claim 1, characterized in that, The feedback control and early warning module includes a three-level early warning mechanism. During the jacking process, this mechanism dynamically triggers different levels of early warning and response measures based on the comparison of monitoring data and thresholds of axis deviation, structural stress, and temporary support reaction force.

5. The system according to claim 1, characterized in that, The core of the construction adjustment instructions generated by the feedback control and early warning module includes: jacking synchronization adjustment instructions, lateral correction instructions, and jacking sequence pause / continue instructions; wherein, the jacking synchronization adjustment instructions are generated based on the monitoring data of axis deviation, guide beam deflection, and structural stress through the hierarchical control logic shown in Figure 5.

6. A construction monitoring method using the system described in any one of claims 1-5, characterized in that, The method places monitoring of the pushing process at its core and includes the following steps: S1: Preliminary preparation stage: Establish the construction control finite element model as shown in Figure 4, determine the theoretical control target values ​​for each construction stage, and complete the on-site deployment of the sensing and monitoring modules. S2: Real-time data acquisition stage: During key processes of bridge construction, especially in multiple cycles of overall jacking, high-frequency acquisition of main beam axis, guide beam alignment, temporary support status, and key section stress data is conducted. S3: Data Analysis and Status Identification Stage: Input the real-time collected data into the calculation analysis and simulation module, compare it with the theoretical calculation results of the model shown in Figure 4, identify errors and evaluate the structural status. This stage focuses on error analysis and structural safety assessment under the jacking condition. S4: Feedback Control Stage: Based on the analysis results, construction control instructions are generated and issued to dynamically adjust the construction. The core of this stage is to dynamically intervene and adjust the synchronicity, alignment and safety status of the jacking process. S5: Iterative phase: Repeat steps S2 to S4 until the jacking construction is successfully completed.

7. The method according to claim 6, characterized in that, In step S2, the key process is centered on overall jacking and includes the main beam and main arch assembly, system conversion and bridge deck paving.

8. The method according to claim 6, characterized in that, In step S3, the error analysis during the jacking stage includes comparing the measured value of the tie beam axis deviation with the theoretical value and the allowable value (≤10mm) in the specification.

9. The method according to claim 6, characterized in that, In step S4, when abnormal deviation of the main beam axis, abnormal stress of the guide beam or abnormal reaction force of the temporary support are detected during the jacking process, the system generates and executes a series of instructions from adjusting the jacking speed, activating lateral correction to emergency stop of jacking according to the hierarchical control logic shown in Figure 5.

10. The method according to claim 6, characterized in that, Before and during the jacking operation, the stability of the steel guide beam and temporary steel support is verified by the calculation analysis and simulation module to ensure the overall structural stability during the jacking process.

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