Bridge incremental launching construction monitoring method and system based on multi-source data fusion

Abstract

The invention provides a bridge incremental launching construction monitoring method and system based on multi-source data fusion, and the method comprises the steps: obtaining the strain and temperature data of a box girder in real time in a non-incremental launching state, and judging whether a construction environment is abnormal or not according to the strain and temperature data of the box girder; in the pushing state, posture data of the box girder, stress and strain of the box girder and displacement of the temporary piers are obtained in real time, and real-time deviation correction or manual intervention is conducted according to the posture data of the box girder, the stress of the box girder and the displacement of the temporary piers. By detecting multi-source data such as jacking, pushing, deviation correction displacement, structural strain, temperature and oil pressure, real-time deviation correction and construction environment adjustment are achieved, the pushing precision can be guaranteed, and structural instability is avoided.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a bridge jacking construction monitoring method and system based on multi-source data fusion. Background Technology

[0002] In applications involving long-span beam bridges, it is typically required that traffic or navigation not be affected. Therefore, among mainstream construction methods such as cantilever casting, incremental launching, whole-span erection, and segmental assembly, incremental launching has become the preferred method for crossing areas with special requirements due to its advantages of low interference, low cost, high precision, short construction period, and strong safety. As the span of bridges constructed using the incremental launching method increases year by year, the negative bending moment and reaction force of the front beams during construction also gradually increase. The alternation of positive and negative bending moments on various sections leads to frequent system transitions and stress redistribution at joints, reducing bridge safety. To ensure safe and efficient construction, close monitoring of the entire construction process is essential. Currently, traditional manual on-site monitoring methods are inefficient, labor-intensive, and prone to errors, making them increasingly inadequate for the ever-increasing scale of large-scale bridge construction. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a bridge jacking construction monitoring method and system based on multi-source data fusion. By detecting multi-source data such as jacking, pushing, correction displacement, structural strain, temperature, and oil pressure, real-time correction and construction environment adjustment can be achieved, ensuring jacking accuracy and preventing structural instability.

[0004] To address the aforementioned technical problems, this invention provides, on the one hand, a bridge jacking construction monitoring method based on multi-source data fusion, comprising: In non-jacking mode, the strain and temperature data of the box girder are acquired in real time, and the construction environment is judged based on the strain and temperature data of the box girder. During the jacking process, the attitude data, stress and strain of the box girder, and displacement of the temporary piers are acquired in real time. Based on the attitude data, stress, and displacement of the box girder, real-time correction or manual intervention is performed.

[0005] In some embodiments, determining whether the construction environment is abnormal based on the strain and temperature data of the box girder includes: The monitored temperature data is substituted into the relationship function between the static length of the box girder and temperature to calculate the strain of the box girder; If the deviation between the monitored strain data and the strain calculated through the relational function exceeds the threshold, an alarm will be triggered and a prompt will be made to check the construction equipment or environmental conditions.

[0006] In some embodiments, real-time correction or manual intervention based on the box girder's attitude data, stress, and displacement of temporary piers includes: The box girder's attitude data includes the jacking displacement at various points on the box girder. The deviation of the jacking displacement at various points on the box girder is calculated. If the deviation of the jacking displacement at any two points is greater than the preset maximum allowable height difference, the jacking is stopped immediately, and manual adjustment of the shims is coordinated.

[0007] In some embodiments, real-time correction or manual intervention based on the box girder's attitude data, stress, and displacement of temporary piers includes: The attitude data of the box girder includes the lateral displacement at various points on the box girder. The lateral displacement at various points on the box girder is calculated. If the lateral displacement at any point exceeds the preset maximum allowable jacking deviation, the steel girder is adjusted along the transverse direction of the bridge using lateral adjustment jacks.

[0008] In some embodiments, real-time correction or manual intervention based on the box girder's attitude data, stress, and displacement of temporary piers includes: If the stress at any point on the box girder exceeds the preset allowable stress range, an early warning is issued and the jacking is stopped. The cantilever elevation at the end of the box girder is checked to see if it is lower than the support height of the next temporary pier. If so, a manual inspection is conducted to check for temporary materials on the box girder, whether the settlement of the temporary pier meets the requirements, and whether the supporting materials between the temporary pier and the box girder are normal. If there are temporary materials on the box girder, and / or the settlement of the temporary piers does not meet the requirements, and / or the supporting materials between the temporary piers and the box girder are compressed and deformed, then remove the temporary materials, and / or lift the jacks on the temporary piers with insufficient settlement to the design height, and / or replace the supporting materials between the temporary piers and the box girder, and check again whether the end cantilever elevation of the box girder is lower than the support height of the next temporary pier. If so, lift the box girder as a whole so that the end cantilever elevation of the box girder is higher than the support height of the next temporary pier, and continue to push. If there are no problems, the box girder is lifted as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking continues.

[0009] In some embodiments, real-time correction or manual intervention based on the box girder's attitude data, stress, and displacement of temporary piers includes: If the deformation of the temporary pier causes its top horizontal displacement to exceed the warning value for the temporary pier's horizontal displacement, then the jacking force at this time is calculated and taken as the maximum allowable jacking force. The temporary pier is then reinforced and jacking continues. The jacking force during subsequent jacking shall not exceed the maximum allowable jacking force.

[0010] In some embodiments, real-time correction or manual intervention based on the box girder's attitude data, stress, and displacement of temporary piers includes: If the settlement of the temporary pier exceeds the settlement warning value, the temporary pier will be reinforced and the support on the temporary pier will be raised back to the design elevation. The cantilever elevation of the end of the box girder will be checked to see if it is lower than the support height of the next temporary pier. If so, the box girder will be raised as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking will continue. Otherwise, the jacking will continue directly.

[0011] In some embodiments, the method for controlling the synchronous pushing of the jacks during the jacking state includes: One jack on each pier is used as the reference jack for the rest of the jacks on that pier. The real-time displacement of the reference jack is used as the reference value. The other jacks on the pier corresponding to the reference jack are corrected in the direction closer to the reference value. The reference jack on one pier is used as the total reference jack. The real-time displacement of the total reference jack is used as the total reference value. The rest of the reference jacks are corrected in the direction closer to the total reference value.

[0012] On the other hand, the present invention provides a system for implementing the bridge jacking construction monitoring method based on multi-source data fusion, comprising: The monitoring system is used to collect static strain and temperature data of the box girder in non-construction state, and to collect the attitude, stress and temporary pier displacement data of the box girder in construction state. The data processing and control unit is used to receive and process the data from the monitoring system and determine whether the construction environment is abnormal and whether correction or manual intervention is required. The actuator unit includes a three-way jacking mechanism, which is used to receive control commands from the data processing and control unit and perform jacking and correction actions; The human-computer interaction unit is used to display monitoring data and early warning information, and provides an interface for automatic control and manual intervention.

[0013] In some embodiments, the monitoring system includes a distance sensor, a strain sensor, a stress-temperature combined sensor, a total station, and a level. The distance sensor is used to monitor the jacking displacement, jacking displacement, and transverse displacement of the box girder. The strain sensor is used to monitor the strain at various points on the box girder. The stress-temperature combined sensor is used to monitor the stress and temperature at various points on the box girder. The total station and level are used to monitor the horizontal displacement and settlement of the temporary piers.

[0014] In some embodiments, the strain sensor and stress-temperature combined sensor are installed at the center of the cast-in-place section at the pier top, at the support section of the pier, at the mid-span section of the main span, at the mid-span section of the side span, at the 1 / 4 span section, at the 3 / 4 span section, at the connection between the guide beam and the box girder, and at the inner and outer arc sides of the curved bridge.

[0015] The beneficial effects of this invention are as follows: 1. This invention integrates multi-source data such as jacking, pushing, correction displacement, structural strain, temperature, and hydraulic pressure, and performs data fusion and dynamic correction based on Bayesian estimation and weighted time-series algorithms, eliminating the effects of sensor drift and signal lag. The system achieves precise closed-loop control of the box girder's attitude by adjusting the pressure of each jack in real time through a PID control module with a millisecond-level response speed. This method can control the synchronization accuracy of horizontal pushing to ≤1mm on both sides of the same pier and ≤5mm between piers, and the jacking synchronization accuracy to ≤4mm, ensuring the precise positioning of the box girder's axis and elevation during long-distance, multi-support jacking processes.

[0016] 2. This invention establishes a dynamic model of the overall stress and displacement of a bridge by integrating multi-point stress, strain, displacement, and hydraulic pressure data. It can calculate the differences in reaction force distribution and synchronization errors at each support point in real time. When the stress at a critical section exceeds the limit, the horizontal displacement or settlement of temporary piers exceeds the warning level, or the box girder posture (e.g., jacking deviation > 0.5 mm, lateral offset > 50 mm) is abnormal, the system can immediately issue an early warning and automatically shut down. Simultaneously, it provides specific risk sources (e.g., temporary piers need reinforcement, shims need adjustment, or temporary loads need to be removed) through a human-machine interface, transforming passive response into proactive early warning and effectively preventing structural instability accidents.

[0017] 3. This invention achieves real-time separation and correction of temperature stress and construction stress by deploying stress-temperature dual-sensor at key cross-sections and combining it with a thermal stress analytical model. The system can automatically identify signal changes caused by ambient temperature fluctuations, avoiding false alarms.

[0018] 4. This invention not only enables real-time correction during jacking operations, but also allows for the prediction of abnormal construction environments (such as equipment malfunctions) through static data analysis during non-construction periods. By programming the control logic, it significantly reduces manual intervention and intermittent measurement time, achieving continuous and stable jacking operations. Engineering examples demonstrate that this system can successfully handle multiple exceeding-limit conditions, ensuring continuous jacking, thereby greatly shortening the construction period and reducing labor costs. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the bridge jacking construction monitoring system based on multi-source data fusion according to the present invention; Figure 2 This is a schematic diagram of the box girder jacking construction of the present invention; Figure 3 This is a control schematic diagram of the actuator unit of the present invention; Figure 4 This is a diagram showing the stress and vertical displacement data of the box girder and guide beam of the present invention; Figure 5 This is a summary diagram of the temporary pier support reaction force data for this invention; Figure 6 This is a schematic diagram of the three-way jacking mechanism of the present invention. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0021] In the current field of bridge jacking construction, traditional monitoring systems generally rely on single displacement or hydraulic signals as control basis, lacking comprehensive perception capabilities of structural stress, temperature field, and multi-point synchronization. This makes it difficult to achieve coordinated control of multiple supports during long-distance continuous jacking. When temporary piers experience uneven stress or guide beams experience torsion, the system often reacts with lag, failing to provide early warning of structural instability risks. This is especially true in day-night construction environments with significant temperature differences, where the additional stress caused by thermal expansion and contraction of steel beams is not effectively incorporated into the monitoring model. This problem is particularly prominent in the jacking of large continuous beams and the construction of multi-pier bridges in mountainous areas, becoming a core bottleneck restricting the automation and intelligent safety of bridge jacking construction.

[0022] This invention addresses the aforementioned problems by constructing a bridge jacking construction monitoring system based on multi-source data fusion. By incorporating jacking displacement, jacking displacement, correction displacement, structural strain, temperature field, and hydraulic pressure data into a single fusion framework, a dynamically correlated set of monitoring parameters is formed. The system treats each jacking point as an independent measurement and control unit, achieving synchronous data transmission through a real-time control network. The main controller establishes a dynamic model of the overall stress and displacement of the bridge after fusing multi-modal signals. This model can calculate the synchronization error and stress distribution differences at each support point in real time during the jacking process, thereby providing the control program with a decision-making basis based on multivariate feedback, significantly improving control accuracy and response speed.

[0023] The system utilizes distributed sensor units to continuously sample the structural state. Cable displacement sensors record the longitudinal and transverse displacement changes of the box girder, strain gauges acquire stress data at key sections, temperature sensors capture local temperature differences, and hydraulic sensors provide real-time feedback on the working pressure of each jack. All acquired signals are filtered and time-synchronized before being input to the main controller's data fusion module. This module, based on Bayesian estimation and weighted time-series algorithms, performs correlation analysis and dynamic correction on multi-source data, thereby eliminating the effects of sensor drift and signal hysteresis and achieving self-consistent processing of multi-dimensional measurement data.

[0024] During the jacking control process, the system's PID control module adjusts the pump station's output pressure in real time based on the fused displacement and force information, achieving multi-point synchronous control through coupled calculations of proportional, integral, and derivative parameters. This control closed loop completes its response within a millisecond timescale, ensuring the dynamic stability of the box girder's attitude and stress state during the jacking process.

[0025] For adaptive correction of environmental impacts, the system installs a combined stress and temperature sensor at the stress monitoring section, and corrects the structural stress value in real time through a thermal stress analysis model. When fluctuations in ambient temperature or changes in sunlight cause thermal deformation of the steel beam, the system can automatically distinguish between the components of temperature stress and construction stress, thereby avoiding false alarms. Monitoring data for the temporary pier section is supplemented by joint measurements using a total station and a level. The controller determines the presence of unbalanced horizontal forces based on the ratio of oil pressure change rate to displacement increment, and actively unloads or adjusts the support reaction force through control strategies.

[0026] The multi-source data fusion monitoring method of this invention, applied in bridge jacking construction, achieves a transformation from single-parameter monitoring to multi-physics field coupled sensing, breaking the limitation of "single displacement monitoring" in traditional jacking systems. Through the collaborative mechanism of data fusion, model feedback, and adaptive control, potential risks can be dynamically identified in complex construction environments, enabling real-time monitoring and intelligent early warning throughout the entire bridge jacking process. This method has good engineering versatility and can be extended to various structural forms such as continuous beams, steel-concrete composite beams, and box girder jacking, providing reliable technical support for the digitalization and intelligentization of bridge construction.

[0027] like Figure 1 As shown, this invention provides a bridge jacking construction monitoring system based on multi-source data fusion, comprising: The monitoring system is used to collect static strain and temperature data of the box girder in non-construction state, and to collect the attitude, stress and temporary pier displacement data of the box girder in construction state. The data processing and control unit, including the real-time control system software module, is used to receive and process data from the monitoring system and determine whether the construction environment is abnormal and whether correction or manual intervention is required.

[0028] The actuator unit includes the pump station electronic control unit and the three-way jacking mechanism, such as... Figure 3 As shown, the pump station's electronic control unit receives control commands from the data processing and control unit, and sends pushing and correction commands to the three-way jacking mechanism; the three-way jacking mechanism (i.e. Figure 3 The jacking equipment in the middle is an existing device that can realize the upward jacking, forward jacking, and transverse jacking of the box girder.

[0029] The human-computer interaction unit is used to display monitoring data and early warning information, and provides an interface for automatic control and manual intervention.

[0030] The monitoring system includes sensor units, total station, and level. The sensor units include distance sensor, strain sensor, and stress-temperature combined sensor.

[0031] Distance sensors are used to monitor the lifting displacement, pushing displacement, and transverse displacement of the box girder, i.e., the pushing displacement in each direction of the three-way pushing mechanism. The distance sensors are rope sensors.

[0032] Strain sensors are used to monitor the longitudinal strain at various points on the box girder. The strain sensors are steel wire strain gauges.

[0033] The stress-temperature combined sensor is used to monitor the longitudinal stress and temperature at various points on the box girder.

[0034] Strain sensors and stress-temperature combined sensors should be installed at critical sections of the steel beam. Critical sections include the center of the cast-in-place section at the pier top, the support section of the pier, the mid-span section of the main span, the mid-span section of the side span, the 1 / 4 span section, the 3 / 4 span section, the connection between the guide beam and the box girder, and the inner and outer arc sides of the curved bridge.

[0035] Total station and level are used to monitor the horizontal displacement and settlement of temporary piers.

[0036] Based on the above system, this invention provides a bridge jacking construction monitoring method based on multi-source data fusion, comprising: S1. In the non-jacking state, the strain and temperature data of the box girder are acquired in real time, and the construction environment is judged based on the strain and temperature data of the box girder. Sensors are used to collect the temperature along the length of the static box girder. A corresponding relationship function is fitted based on the relationship between temperature change and the length of the box girder. The real-time monitored temperature is substituted into the relationship function to obtain the length of the steel beam. When calculating the strain of the box girder, if the deviation between the monitored strain data and the strain calculated by the relationship function exceeds a threshold, an alarm is triggered and a prompt is made to check the construction equipment or environmental conditions. For example, check for hidden dangers in the jacking system and check the displacement of temporary piers.

[0037] S2. In the jacking state, the attitude data, stress and strain of the box girder, and displacement of the temporary pier are acquired in real time. Based on the attitude data, stress, and displacement of the box girder, real-time correction or manual intervention is performed.

[0038] S21. The attitude data of the box girder includes the jacking displacement and lateral displacement at various points on the box girder.

[0039] By retrieving the absolute elevations of at least four distance sensors located below the box girder and above the pad, the elevation difference between the two distance sensors is calculated, which represents the deviation of the box girder's jacking displacement at that location. Special attention is paid to the height difference between the top surfaces of the sliding devices at the two supports on the same pier. If the deviation of the jacking displacement at any two locations exceeds the preset maximum allowable height difference (generally taken as 0.5mm, meaning the absolute value of the jacking displacement deviation is no greater than 0.5mm), the jacking should be stopped immediately, and manual adjustment of the pad should be coordinated.

[0040] Calculate the lateral displacement at each point of the box girder. If any lateral displacement exceeds the preset maximum allowable jacking deviation (generally taken as 50mm), then use lateral adjustment jacks to adjust the steel beam along the transverse direction of the bridge to ensure that the web of the box girder and the guide beam is always within ±50mm of the longitudinal centerline of the jacking equipment during the jacking process.

[0041] S22. If the stress at a certain point on the box girder exceeds the preset allowable stress range for that point (the allowable stress range for each point is determined based on the simulation results of the jacking model and should fluctuate within a certain range of the simulation results), an early warning is issued and jacking is stopped. The cantilever elevation at the end of the box girder is checked to see if it is lower than the support height of the next temporary pier. If so, a manual inspection is conducted to check for temporary materials on the box girder, whether the settlement of the temporary pier meets the requirements, and whether the supporting materials between the temporary pier and the box girder are normal. If there are temporary materials on the box girder, and / or the settlement of the temporary piers does not meet the requirements, and / or the supporting materials between the temporary piers and the box girder are compressed and deformed, then remove the temporary materials, and / or lift the jacks on the temporary piers with insufficient settlement to the design height, and / or replace the supporting materials between the temporary piers and the box girder, and check again whether the end cantilever elevation of the box girder is lower than the support height of the next temporary pier. If so, lift the box girder as a whole so that the end cantilever elevation of the box girder is higher than the support height of the next temporary pier, and continue to push. If there are no problems, the box girder is lifted as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking continues.

[0042] It should be noted that during the jacking process, except for the jacking points where the box girder contacts the jacking equipment, the rest of the box girder is in a suspended or cantilevered state, especially the foremost part of the box girder, which is partially cantilevered. Partial cantilever can lead to deformation of the box girder. This invention places sensors at eight specific key sections, and the data collected by the sensors can be compared with the data of the jacking model. If the stress at the key sections changes significantly, it indicates that there are discrepancies between the on-site conditions and the model during construction. For example, a possible phenomenon is that the cantilever elevation of the end of the box girder is lower than the support height of the next temporary pier. In this case, the box girder cannot continue to be jacked to the pier, and the existing support needs to be raised as a whole before continuing to jack to the next temporary pier and lowering the girder. Usually, a model simulating the cantilever posture of the box girder during the jacking process is created before construction, but the actual construction state may differ from the model state. The reasons for this may include: temporary materials or equipment above the box girder causing the weight of a certain part of the steel beam to be inconsistent with the model, settlement of the temporary pier, compression deformation of the support material between the temporary pier and the box girder, etc.

[0043] S23. If the deformation of the temporary pier causes its top horizontal displacement to exceed the warning value of the temporary pier, calculate the jacking force at this time, take the jacking force at this time as the maximum allowable jacking force, reinforce the temporary pier, and continue jacking. The jacking force in subsequent jacking shall not exceed the maximum allowable jacking force.

[0044] Among them, the pipeline oil pressure P can be used to determine and Where d is the pipe diameter, Let be the oil pressure of the i-th pipeline. If the settlement of the temporary pier exceeds the settlement warning value, the temporary pier will be reinforced, and the support on the temporary pier will be raised back to the design elevation. Check whether the cantilever elevation of the end of the box girder is lower than the support height of the next temporary pier. If so, the box girder will be raised as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking will continue. Otherwise, the jacking will continue directly.

[0045] Monitoring of temporary piers is conducted using total stations, levels, and other monitoring instruments at a frequency of once every 30 minutes. Observation points are arranged on the three-way jacking mechanism, with no fewer than two support horizontal displacement, deformation monitoring, and settlement observation points arranged along the longitudinal bridge axis for each three-way jacking mechanism. The top of the temporary pier, the overall horizontal displacement of the temporary pier, and the settlement deformation of the temporary pier should all not exceed 10mm. If the value exceeds the warning value of 100mm, the system will issue a warning, stop the jacking construction, and coordinate manual reinforcement. S24. In the jacking state, the methods for controlling the synchronous jacking of the jacking jack include: One jack on each pier is used as the reference jack for the rest of the jacks on that pier. The real-time displacement of the reference jack is used as the reference value. The other jacks on the pier corresponding to the reference jack are corrected in the direction closer to the reference value. The reference jack on one pier is used as the total reference jack. The real-time displacement of the total reference jack is used as the total reference value. The rest of the reference jacks are corrected in the direction closer to the total reference value.

[0046] In addition, before the multiple three-way jacking mechanisms are simultaneously jacked, they need to be pre-jacked to ensure they are in contact with the bottom surface of the box girder. The pre-jacking force is set to 300kN. During the jacking process, a dedicated person is responsible for controlling the human-machine interface. By controlling the flow of each proportional valve, the synchronization accuracy of the horizontal jacking jacks can be controlled within 5mm between each pier, and within 1mm on both sides of the same pier. The synchronization accuracy of jacking and lowering can be controlled within 4mm. Pressure sensors are installed on the jacks to monitor the load at each force point. During the jacking process, the reaction force of each three-way jacking mechanism is compared with the modeling calculation results. If the difference exceeds the theoretical value by 10%, construction should be suspended and a manual re-inspection and verification should be organized.

[0047] The steps S1, S2, etc. mentioned above do not indicate the order of the steps.

[0048] (1) The expected benefits and commercial value of the technical solution of this invention after transformation are as follows: Current engineering practices have validated the benefits of similar intelligent monitoring technologies—by integrating IoT, BeiDou positioning, and multi-sensor parameters, it is possible to achieve a synchronization error of ≤0.5 mm in jacking (as seen in the equipment of Shandong Road & Bridge), and shorten the construction period by 32%-65% (as demonstrated by the digital twin platform of the Bridge Science Institute and the Zhejiang jacking case). In projects such as the Chengdu-Chongqing Central Line, single projects have saved over 100 million yuan in costs. These efficiency improvements are highly attractive in the trillion-dollar global bridge construction market expected by 2025. With the continued growth of China's domestic and international bridge engineering markets, this invention can capture a niche market through patent licensing, intelligent system sales, and solution output. Assuming a penetration rate of only 1%, it could generate billions of yuan in revenue. Its standardized model can also be replicated in overseas projects (currently, overseas orders account for 15%), further expanding its commercial boundaries. This invention can form a high-premium intelligent solution in the trillion-dollar bridge construction market, and its profit margins will continue to expand with technology standardization and overseas export.

[0049] (2) The technical solution of this invention fills a technical gap in the industry both domestically and internationally: This invention details a bridge jacking construction monitoring method based on multi-source data fusion, including... 1. Improve the types of monitoring data for bridge jacking, and enhance the efficiency, accuracy, and safety of jacking construction by making the data from multiple sources more refined and comprehensive. Propose detailed placement locations for various strain gauges, and obtain the necessary data for subsequent control, such as the box girder lifting displacement and jacking displacement.

[0050] 2. To address settlement and unbalanced horizontal forces, a bridge jacking construction monitoring system is proposed, which includes monitoring hydraulic jack pressure data, calculating support reaction force using formulas, transmitting the data back to the PIC control center in real time, recalibrating the jacking force, and implementing a closed-loop correction system.

[0051] 3. Provide a detailed explanation of the structure, function, and physical connections of the sensor units, real-time control system software modules, real-time control network, and pump station electronic control units required for the bridge jacking construction monitoring system, forming a closed-loop system for data monitoring, data feedback, data analysis, and construction guidance for jacking construction.

[0052] This embodiment provides a specific engineering example to illustrate the technical content of the above embodiments.

[0053] A bridge spans a river, with a main girder made of steel-concrete composite beam. It is 244.72 meters long and 47 meters wide, with a 2% cross slope on both sides of the top surface. The bridge span arrangement is as follows: Figure 2 As shown.

[0054] The specific monitoring plan for this bridge is as follows: 1. Overall posture monitoring of steel beams Using a theodolite, four coordinate observation points are set on the bottom surface of the steel beam at each temporary pier location. After each push is completed, the monitoring team will measure and collect data, and calculate the maximum allowable height difference of the box girder without needing to adjust the pads. If the height difference of the box girder exceeds the allowable range, construction must be stopped immediately and the pads adjusted.

[0055] 2. Monitoring of construction displacement and box girder centerline offset Pull rope sensors are installed at the front end, rear end, and web of the box girder. During construction, the measured values ​​are displayed in real time on the human-machine interface of the main control console. If the value exceeds the allowable range of 100mm, the PID control system issues an early warning and stops the jacking.

[0056] 3. Temporary pier foundation settlement monitoring Monitoring instruments such as total stations, theodolites, and levels are used to monitor the horizontal displacement, deformation, and settlement of the temporary piers every 30 minutes. At least two monitoring points for horizontal displacement, deformation, and settlement are set up along the longitudinal bridge axis. The warning values ​​for the horizontal displacement and settlement of the temporary piers are both 10 mm. If the warning value is exceeded, the system will issue an alert, stop the jacking construction, and coordinate manual reinforcement.

[0057] 4. Monitoring of Temporary Pier Support Reactions Accurate calculation of the reaction force of the temporary pier is crucial to determining the jacking force at each point. Excessive unbalanced horizontal forces on the temporary pier should be avoided during construction. The reaction force of the temporary pier is primarily measured using hydraulic pressure measuring equipment, and then indirectly calculated.

[0058] 5. Stress monitoring of main beam structure Twelve steel wire strain gauges are planned to be installed on each key control section of the box girder to measure the longitudinal stress of the steel beam structure and transmit it to the main controller in real time. During the jacking process, if the stress exceeds the allowable range, an early warning will be issued and the segmented beam will be stopped.

[0059] 6. Synchronous top-push early warning After the lifting jack piston extends and lifts the box girder, the pushing jack piston extends and pushes the girder forward. This process requires displacement synchronization control, pressure equalization control, and lateral adjustment control. In addition to controlling the unified action of all pushing jacks on all piers, the main control console must also ensure the synchronization of each stroke of all pushing jacks. The control strategy is as follows: among the horizontal pushing jacks on the same pier, jack #1 is the active point, extending its cylinder at a certain speed. The other horizontal jacks are the follower points and are compared with jack #1. The displacement difference between each jack and jack #1 is controlled within a set value. If a jack extends its cylinder faster, the flow rate of the corresponding proportional valve is reduced; conversely, the flow rate of the corresponding proportional valve is increased. The synchronization control method for horizontal pushing jacks on different piers is as follows: jack #1 on pier #1 is the active point, and the jacks #1 on the other piers are compared with it. If a jack extends its cylinder faster, the flow rate of the corresponding proportional valve is reduced; conversely, the flow rate of the corresponding proportional valve is increased, thereby achieving synchronization of all horizontal pushing jacks. The synchronization accuracy during this process can be controlled within 5mm between each pier, and within 3mm between the two sides of the same pier. Based on sensitivity analysis, the maximum allowable asynchronous error for the jacking equipment is ≤30mm, and the actual system setting allows a maximum allowable deviation of ≤10mm. Synchronization control is not required for the jacking jack retraction cylinder.

[0060] Each jack is equipped with a pressure sensor to monitor load changes. The maximum pressure of each jack and the maximum pressure difference between jacks on the same pier can be set via the field controller or the panel on the main control console. The computer monitors the load changes of each jack to accurately coordinate the load distribution of the entire system. If the load on a jack reaches the set maximum pressure or the maximum pressure difference between jacks on the same pier exceeds the set value, the system will automatically shut down and issue a warning.

[0061] 7. Early warning system for box girder balance control Each pier's sliding box is equipped with an inclination sensor to detect the tilt angle of the box girder in the X and Y axes. Therefore, by setting the maximum tilt angle of each inclination sensor in the X and Y axes, the balance of the box girder can be controlled. If any inclination sensor's tilt angle in the X or Y axis exceeds the set value, the system will stop and issue a warning.

[0062] like Figure 4 As shown, this application example sets up 29 bridge jacking conditions. Stress and vertical displacement data for the box girder and guide beam can be obtained from stress and displacement sensor data. Analysis shows that during construction up to condition 19, the maximum stress value of the steel beam is 93.1 MPa; the maximum total reaction force of a single cross section is 22437 kN, occurring in condition 23; the maximum stress of the guide beam is 215 MPa, occurring in condition 14; and the maximum vertical deformation of the guide beam is 159 mm, occurring in condition 13. In summary, a total of 5 exceeding-limit conditions occurred, prompting a halt to jacking and correction.

[0063] This application example focuses on monitoring the reaction force of temporary pier supports, taking temporary pier L1 as an example, and dividing it into 4 working conditions: (1) In the jacking operation, the equipment is arranged on the inner side. Consider the temporary pier structure bearing the vertical load of jacking, the longitudinal horizontal load, the wind load, and the load of construction personnel and equipment.

[0064] (2) In the jacking operation, the equipment is arranged on the outside. Consider the temporary pier structure bearing the vertical load of jacking, the longitudinal horizontal load, the wind load, and the load of construction personnel and equipment.

[0065] (3) Correction condition: The equipment is arranged on the inner side, taking into account the temporary pier structure bearing the vertical load of jacking, the lateral adjustment load, the wind load, and the load of construction personnel and equipment.

[0066] (4) Correction condition: the equipment is arranged on the outside, and the temporary pier structure is considered to bear the vertical load of the jacking, the lateral adjustment load, the wind load and the load of construction personnel and equipment.

[0067] Measurement of temporary pier support reaction force, such as Figure 5 As shown, the maximum stress can be calculated. It is located in the middle of the longitudinal beam. The maximum displacement is 29.1mm. At this point, the jacking construction is stopped and the correction is initiated.

[0068] Combination Figure 6 The structure shown comprises a hydraulic drive subsystem, a network of sub-control pump stations, a main control unit, and an intelligent control terminal. The hydraulic drive section includes multiple jacking devices numbered 1 to 8, each connected to its corresponding hydraulic pump station sub-control unit via oil pipes and sensor communication lines. Each pump station forms a local closed loop with an electronically controlled proportional valve and an oil pressure sensing module to achieve synchronized movement and real-time pressure feedback of the jacking cylinders. The main control unit forms a master-slave control network with each sub-control pump station via pump station communication lines, with data and control signals cyclically transmitted on the CAN bus at millisecond intervals. The intelligent control terminal embeds control algorithms and a visual interface to display jacking displacement, oil pressure, displacement error, and synchronization status, and to identify and warn of abnormal signals.

[0069] From the perspective of mechanical transmission path, the three-way jacking mechanism includes a lower support, lifting cylinders, pushing cylinders, longitudinal sliding blocks, transverse sliding blocks, and correction cylinders. The lifting cylinders are arranged vertically and support the upper bridge segments, providing vertical support force through a hydraulic system to counteract their own weight. The pushing cylinders are arranged longitudinally along the bridge direction, forming a thrust force to jack the beam through a piston rod connected to the sliding block. The transverse sliding blocks and correction cylinders are arranged transversely along the bridge direction to correct the axial misalignment between the guide beam and the box girder. The bottom of each cylinder and the lower support form a closed support system, bearing both vertical reaction forces and providing a stable base for lateral and longitudinal sliding.

[0070] During system operation, the cylinder movements of each jacking device are controlled by commands from the hydraulic pump station sub-control module. The main control unit collects real-time data from the pressure and displacement sensors of each cylinder, calculates the actual thrust and stroke difference at each support point, and dynamically adjusts the hydraulic pressure output based on a PID control algorithm. The switching between the lifting cylinder and the pushing cylinder is controlled by a three-position four-way solenoid valve to ensure stable thrust during the jacking phase and depressurization and reset during the return phase. Speed ​​regulation between each hydraulic circuit is achieved through throttle valves to ensure jacking synchronization and smoothness. The system uses a data fusion algorithm to dynamically weight signals from multiple points, thereby obtaining a real-time mapping of the overall bridge attitude and force distribution.

[0071] When the monitoring system detects that the pressure fluctuation or displacement error at any support point exceeds the set threshold, the main control equipment immediately sends a flow restriction or pump stop command to the corresponding pump station through the communication network, and simultaneously displays the abnormal status on the intelligent control terminal interface. If the axis offset exceeds the allowable range, the correction cylinder initiates lateral adjustment to straighten the beam. This working mechanism forms a closed-loop process of "perception-decision-control-feedback," enabling the multi-support jacking equipment to maintain mechanical coordination and structural safety in complex environments, thereby ensuring the continuity and stability of bridge jacking construction.

[0072] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A bridge jacking construction monitoring method based on multi-source data fusion, characterized in that: include: In non-jacking mode, the strain and temperature data of the box girder are acquired in real time, and the construction environment is judged based on the strain and temperature data of the box girder. During the jacking process, the attitude data, stress and strain of the box girder, and displacement of the temporary piers are acquired in real time. Based on the attitude data, stress, and displacement of the box girder, real-time correction or manual intervention is performed.

2. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Determining whether the construction environment is abnormal based on the strain and temperature data of the box girder includes: The monitored temperature data is substituted into the relationship function between the static length of the box girder and temperature to calculate the strain of the box girder; If the deviation between the monitored strain data and the strain calculated through the relational function exceeds the threshold, an alarm will be triggered and a prompt will be made to check the construction equipment or environmental conditions.

3. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Real-time correction or manual intervention based on the box girder's posture data, stress, and temporary pier displacement includes: The box girder's attitude data includes the jacking displacement at various points on the box girder. The deviation of the jacking displacement at various points on the box girder is calculated. If the deviation of the jacking displacement at any two points is greater than the preset maximum allowable height difference, the jacking is stopped immediately, and manual adjustment of the shims is coordinated.

4. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Real-time correction or manual intervention based on the box girder's posture data, stress, and temporary pier displacement includes: The attitude data of the box girder includes the lateral displacement at various points on the box girder. The lateral displacement at various points on the box girder is calculated. If the lateral displacement at any point exceeds the preset maximum allowable jacking deviation, the steel girder is adjusted along the transverse direction of the bridge using lateral adjustment jacks.

5. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Real-time correction or manual intervention based on the box girder's posture data, stress, and temporary pier displacement includes: If the stress at any point on the box girder exceeds the preset allowable stress range, an early warning is issued and the jacking is stopped. The cantilever elevation at the end of the box girder is checked to see if it is lower than the support height of the next temporary pier. If so, a manual inspection is conducted to check for temporary materials on the box girder, whether the settlement of the temporary pier meets the requirements, and whether the supporting materials between the temporary pier and the box girder are normal. If there are temporary materials on the box girder, and / or the settlement of the temporary piers does not meet the requirements, and / or the supporting materials between the temporary piers and the box girder are compressed and deformed, then remove the temporary materials, and / or lift the jacks on the temporary piers with insufficient settlement to the design height, and / or replace the supporting materials between the temporary piers and the box girder, and check again whether the end cantilever elevation of the box girder is lower than the support height of the next temporary pier. If so, lift the box girder as a whole so that the end cantilever elevation of the box girder is higher than the support height of the next temporary pier, and continue to push. If there are no problems, the box girder is lifted as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking continues.

6. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Real-time correction or manual intervention based on the box girder's posture data, stress, and temporary pier displacement includes: If the deformation of the temporary pier causes its top horizontal displacement to exceed the warning value for the temporary pier's horizontal displacement, then the jacking force at this time is calculated and taken as the maximum allowable jacking force. The temporary pier is then reinforced and jacking continues. The jacking force during subsequent jacking shall not exceed the maximum allowable jacking force.

7. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: Real-time correction or manual intervention based on the box girder's posture data, stress, and temporary pier displacement includes: If the settlement of the temporary pier exceeds the settlement warning value, the temporary pier will be reinforced and the support on the temporary pier will be raised back to the design elevation. The cantilever elevation of the end of the box girder will be checked to see if it is lower than the support height of the next temporary pier. If so, the box girder will be raised as a whole so that the cantilever elevation of the end of the box girder is higher than the support height of the next temporary pier, and the jacking will continue. Otherwise, the jacking will continue directly.

8. The bridge jacking construction monitoring method based on multi-source data fusion according to claim 1, characterized in that: In the jacking state, the methods for controlling the synchronous jacking of the jacking jacks include: One jack on each pier is used as the reference jack for the rest of the jacks on that pier. The real-time displacement of the reference jack is used as the reference value. The other jacks on the pier corresponding to the reference jack are corrected in the direction closer to the reference value. The reference jack on one pier is used as the total reference jack. The real-time displacement of the total reference jack is used as the total reference value. The rest of the reference jacks are corrected in the direction closer to the total reference value.

9. A system for implementing the bridge jacking construction monitoring method based on multi-source data fusion as described in any one of claims 1 to 8, characterized in that: include: The monitoring system is used to collect static strain and temperature data of the box girder in non-construction state, and to collect the attitude, stress and temporary pier displacement data of the box girder in construction state. The data processing and control unit is used to receive and process the data from the monitoring system and determine whether the construction environment is abnormal and whether correction or manual intervention is required. The actuator unit includes a three-way jacking mechanism, which is used to receive control commands from the data processing and control unit and perform jacking and correction actions; The human-computer interaction unit is used to display monitoring data and early warning information, and provides an interface for automatic control and manual intervention.

10. The system according to claim 9, characterized in that: The monitoring system includes a distance sensor, a strain sensor, a stress-temperature combined sensor, a total station, and a level. The distance sensor is used to monitor the lifting displacement, pushing displacement, and transverse displacement of the box girder. The strain sensor is used to monitor the strain at various points on the box girder. The stress-temperature combined sensor is used to monitor the stress and temperature at various points on the box girder. The total station and level are used to monitor the horizontal displacement and settlement of the temporary piers.

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