Bridge jacking safety real-time early warning method and system under pass-through condition

Abstract

The application discloses a bridge jacking safety real-time early warning method and system under the condition of keeping open to traffic, and relates to the technical field of bridge construction. The method comprises the following steps: a multi-source monitoring sensor network is constructed in a bridge jacking construction area to realize time-synchronous collection and preprocessing of sensor data. Based on the synchronous data, three key indexes are calculated: a differential jacking posture deviation index reflecting the consistency of the whole bridge spatial posture by real-time displacement of each jacking point; a traffic-jacking coupled stress safety reserve index reflecting the stress safety margin by traffic load and stress of a key section; and a multi-point synchronous deviation index reflecting the synchronous control accuracy by the deviation between actual displacement and PLC instruction displacement. The three indexes are fused into a comprehensive real-time early warning index, which is compared with multi-level early warning thresholds to determine the early warning level and trigger corresponding response measures.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology, and more specifically, relates to a real-time early warning method and system for bridge jacking safety under conditions of maintaining traffic flow. Background Technology

[0002] like Figure 3 As shown, for the synchronous slope adjustment and jacking project of piers 35#-57# of the old Donghe Bridge, the bridge must maintain normal traffic flow (maintain traffic flow) during the construction period. The existing left and right bridges must be synchronously adjusted to the target slope under the action of the PLC-controlled hydraulic synchronous jacking system.

[0003] Existing jacking safety monitoring technology has the following four limitations: Limitation 1: Decoupling of Traffic Live Load and Lifting Conditions. Existing methods operate structural safety monitoring and traffic live load monitoring as two independent subsystems, failing to establish a real-time coupled analysis model for traffic live load and lifting conditions. Fixed static thresholds cannot reflect the real-time impact of the dynamic amplification effect of live load and the superposition of lifting load on the stress state of critical sections under traffic maintenance conditions, resulting in a systematic bias of overestimating safety margins.

[0004] Limitation 2: Synchronous control alarms rely on single-point displacement thresholds. Although existing synchronous jacking control systems can achieve displacement deviation control, they only use whether the displacement deviation of a single jacking point exceeds the limit as the basis for alarms, failing to comprehensively consider the spatial attitude differences between multiple jacking points of the entire bridge and the different effects of stiffness distribution of different beam segments on attitude deviation sensitivity.

[0005] Limitation 3: The cumulative effect of structural fatigue damage is not considered. Existing early warning methods do not include the fatigue stress cycle of key sections during the jacking process in the safety reserve assessment. During the long-term jacking construction phase, the accumulation of fatigue damage will lead to a systematic underestimation of the structural safety margin.

[0006] Limitation 4: The warning threshold is a static, fixed value. The existing warning threshold remains unchanged throughout the entire construction process and cannot be adaptively adjusted based on the real-time monitoring of the structural safety reserve. This poses a risk of missed warnings when the structural safety reserve has already been depleted.

[0007] Therefore, there is an urgent need for a technical solution that can solve the above technical problems. Summary of the Invention

[0008] To address the above technical problems, this invention proposes a real-time early warning method for bridge jacking safety under traffic maintenance conditions, comprising: A multi-source monitoring sensor network was constructed within the bridge jacking construction area to collect and preprocess data from various sensors in real time, thereby obtaining synchronous sensor data. Based on the real-time lifting displacement of each lifting point in the synchronous sensor data, calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points; Based on real-time traffic load and critical section monitoring stress from synchronous sensor data, calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of critical sections under the combined action of traffic live load and jacking load. The multi-point synchronization deviation index, which measures the accuracy of synchronous control, is calculated based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. The differential lifting attitude deviation index, the traffic-lifting coupling stress safety reserve index, and the multi-point synchronization deviation index are integrated into a comprehensive real-time early warning index. The comprehensive real-time early warning index is compared with the multi-level early warning thresholds to determine the early warning level and trigger corresponding response measures.

[0009] Furthermore, the calculation of the lifting attitude deviation index, which reflects the difference in spatial attitude consistency at the entire bridge lifting point, includes: ,in, For a moment The difference in the lifting attitude deviation index. This represents the total number of lifting points of the hydraulic jacks across the entire bridge. For a moment No. The cumulative lifting displacement of each apex point For a moment No. The cumulative lifting displacement of each apex point For the first The first peak point and the first The horizontal projection distance between each apex point For the first The first peak point and the first The structural stiffness weighting coefficient between the corresponding beam segments at each jacking point.

[0010] Furthermore, the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of critical sections under the combined action of traffic live load and jacking load, includes: ,in, For a moment The traffic-lift coupling stress safety reserve index For a moment Residual allowable stress at critical sections, For a moment The static stress generated by the lifting load at the critical section, For a moment The root mean square value of dynamic stress generated by traffic live loads at critical sections. For a moment Traffic dynamic amplification factor.

[0011] Furthermore, calculate the time. Traffic dynamic amplification factor include: ,in, The roughness influence coefficient of the bridge deck surface. For a moment The average speed of passing vehicles It is the acceleration due to gravity. The calculated span of the lifting beam segment, This is the axle load sensitivity coefficient. For a moment The average equivalent axle load of passing vehicles For reference axle load.

[0012] Furthermore, the calculation of the multi-point synchronization deviation index, which measures the accuracy of synchronous control, includes: ,in, For a moment Multi-point synchronization deviation index For a moment No. The load proportion weight of each apex point For a moment No. The actual cumulative lifting displacement of each lifting point For a moment Displacement via PLC commands issued by the PLC For numerical stability parameters, This represents the total number of lifting points of the hydraulic jacks for the entire bridge.

[0013] Furthermore, the calculation of the comprehensive real-time early warning index includes: ,in, For a moment Comprehensive real-time early warning index, For a moment The ratio of the differential lifting attitude deviation index to the updated threshold. For a moment The ratio of the target safety reserve design value to the traffic-lift coupling stress safety reserve index. For a moment The ratio of the multi-point synchronization deviation index to the preset synchronization deviation threshold. As the first weight, As the second weight, As the third weight, for and Positive coupling correction coefficient between them For a moment Fatigue accumulation correction factor.

[0014] Furthermore, calculate the time. Fatigue accumulation correction factor include: ,in, For fatigue damage weighting, From the start of the lifting operation to the moment The cumulative stress cycle number of the critical section, The design fatigue life cycle count for critical cross-sections. This is the fatigue accumulation rate index.

[0015] Furthermore, determining the warning level and triggering corresponding response measures includes: When the comprehensive real-time early warning index is less than the first early warning threshold, it is determined to be a normal state, and the current lifting rate is maintained to continue the operation; When the comprehensive real-time early warning index is greater than or equal to the first early warning threshold and less than the second early warning threshold, it is judged as a level three early warning, triggering an audible and visual alarm and reducing the lifting rate to less than 50% of the normal rate; When the comprehensive real-time early warning index is greater than or equal to the second early warning threshold and less than the third early warning threshold, it is judged as a level two early warning, the jacking operation is suspended and new vehicles are prohibited from entering the jacking section; When the comprehensive real-time early warning index is greater than or equal to the third early warning threshold, it is determined to be a first-level early warning. The jacking is stopped immediately and all hydraulic jacks are switched to the hydraulic and mechanical dual self-locking state.

[0016] Furthermore, it also includes: When the first-level early warning condition is met for M consecutive main sampling times, an emergency stop command is automatically sent to the PLC main controller. When the comprehensive real-time early warning index does not meet the conditions for a Level 1 early warning, if any one of the differential jacking attitude deviation index, traffic-jacking coupling stress safety reserve index, and multi-point synchronization deviation index exceeds the corresponding single trigger threshold, a Level 2 early warning will be directly triggered, and corresponding response measures will be initiated.

[0017] This invention also proposes a real-time early warning system for bridge jacking safety under traffic maintenance conditions, comprising: The data acquisition module is used to build a multi-source monitoring sensor network in the bridge jacking construction area, and to collect and preprocess the data from each sensor in time synchronization to obtain synchronous sensor data. The first calculation module is used to calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points, based on the real-time lifting displacement of each lifting point in the synchronous sensor data. The second calculation module is used to calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of the key section under the combined action of traffic live load and jacking load, based on the real-time traffic load and key section monitoring stress in the synchronous sensor data. The third calculation module is used to calculate the multi-point synchronization deviation index, which measures the accuracy of synchronous control, based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. The fourth calculation module is used to integrate the differential lifting attitude deviation index, the traffic-lifting coupling stress safety reserve index, and the multi-point synchronization deviation index into a comprehensive real-time early warning index; The early warning module is used to compare the comprehensive real-time early warning index with multi-level early warning thresholds, determine the early warning level, and trigger corresponding response measures.

[0018] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art: 1. By incorporating the real-time driving speed and equivalent axle load of passing vehicles into the calculation of the traffic dynamic amplification factor, a coupled quantitative analysis of the dynamic effect of traffic live load and the influence of jacking load on the stress of key sections is realized for the first time, overcoming the systematic deviation caused by the fixed impact coefficient.

[0019] 2. A positive definite quadratic coupling correction term is introduced between the attitude deviation sub-index and the stress safety reserve sub-index into the comprehensive real-time early warning index. This allows for the explicit quantification of the superposition risk when both indices deviate from the safe state simultaneously, avoiding the problem of underestimating the joint risk by the linear superposition method.

[0020] 3. The early warning index for the long-cycle jacking construction phase is dynamically amplified by the fatigue accumulation correction factor, and the early warning sensitivity is adaptively improved by the threshold tightening mechanism based on the historical minimum safety reserve, forming a complete closed loop from data collection to decision response. Attached Figure Description

[0021] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention; Figure 2 This is a system structure diagram of Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the lifting of piers 35#-57# of the old Donghe Bridge. Detailed Implementation

[0022] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0023] The method provided by this invention can be implemented in a terminal environment that may include one or more of the following components: a processor, a storage medium, and a display screen. The storage medium stores at least one instruction, which is loaded and executed by the processor to implement the method described in the following embodiments.

[0024] A processor may include one or more processing cores. The processor uses various interfaces and lines to connect various parts of the terminal, and performs various functions and processes data by running or executing instructions, programs, code sets or instruction sets stored in the storage medium, and by calling data stored in the storage medium.

[0025] Storage media can include random access memory (RAM) or read-only memory (ROM). Storage media can be used to store instructions, programs, code, code sets, or instructions.

[0026] The display screen is used to show the user interface of each application.

[0027] In addition, those skilled in the art will understand that the structure of the terminal described above does not constitute a limitation on the terminal. The terminal may include more or fewer components, or combine certain components, or have different component arrangements. For example, the terminal may also include radio frequency circuits, input units, sensors, audio circuits, power supplies, and other components, which will not be described in detail here.

[0028] Example 1 like Figure 1 As shown in the figure, this embodiment proposes a real-time early warning method for bridge jacking safety under the condition of maintaining traffic flow, including: Step 101: Construct a multi-source monitoring sensor network within the bridge jacking construction area, and collect and preprocess the data from each sensor in real time to obtain synchronized sensor data. Preferably, the construction of the multi-source monitoring sensor network includes: arranging displacement sensors for collecting cumulative jacking displacement and pressure sensors for collecting the jacking force of hydraulic jacks at each jacking point; arranging strain sensors at the beam end support section, mid-span section, and splicing section of the old and new structures; arranging dynamic weighing equipment at the entrance and exit ends of the jacking section; and achieving network-wide time synchronization through GPS or IEEE 1588 precise time protocol, with a time synchronization accuracy of no more than 1 ms.

[0029] Step 102: Calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points, based on the real-time lifting displacement of each lifting point in the synchronous sensor data. Specifically, the jacking attitude deviation index, which reflects the difference in spatial attitude consistency at the jacking point of the entire bridge, includes: ,in, For a moment The difference in the lifting attitude deviation index. This represents the total number of lifting points of the hydraulic jacks across the entire bridge. For a moment No. The cumulative lifting displacement of each apex point For a moment No. The cumulative lifting displacement of each apex point For the first The first peak point and the first The horizontal projection distance between each apex point For the first The first peak point and the first The structural stiffness weighting coefficients of the corresponding beam segments between each jacking point can be obtained as follows: The value is: 1. equal to the ratio of the overall bridge's reference equivalent bending stiffness to the equivalent bending stiffness of this beam segment; 2. for prestressed concrete standard box girder segments with bending stiffness close to the overall bridge's reference value, For the transition section between the old and new bridges (including the area where the new cap beam is connected). For the modified beam segment after the cantilever arm of the cap beam was removed (within the range of piers 42#-44#). .

[0030] Step 103: Based on the real-time traffic load and the monitored stress of key sections (such as the transition section between the old and new bridges, the modified beam section after the cantilever of the cap beam is removed, the prestressed concrete standard box girder section, etc.) in the synchronous sensor data, calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of key sections under the combined action of traffic live load and jacking load. Specifically, the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of critical sections under the combined action of traffic live load and jacking load, includes: ,in, For a moment The traffic-lift coupling stress safety reserve index For a moment Residual allowable stress at critical sections, , To design allowable stress, For a moment Prestress loss in cross section For a moment The static stress generated by the lifting load at the critical section, For a moment The root mean square value of dynamic stress generated by traffic live loads at critical sections. For a moment Traffic dynamic amplification factor.

[0031] Preferred, Target security reserves Pick This means that the stress at the critical section under traffic-jacking coupling conditions must not exceed the remaining allowable stress. .

[0032] Specifically, calculating the time Traffic dynamic amplification factor include: ,in, This is the influence coefficient of road surface roughness, reflecting the impact of road surface unevenness on the vertical excitation amplitude of vehicles. Example value: When the road surface condition is good (ISO 8608 Class A). When the road surface condition is moderate (Class B) When the road surface condition is poor (Class C) , For a moment The average speed of passing vehicles It is the acceleration due to gravity. The calculated span of the lifting beam segment, This is the axle load sensitivity coefficient, reflecting the contribution of heavy vehicle axle load to dynamic effects. Example value: For urban expressways primarily used by light vehicles... National and provincial trunk lines with mixed traffic as the main mode of transportation Freight routes mainly used by heavy-duty vehicles , For a moment The average equivalent axle load of passing vehicles For reference axle load.

[0033] Step 104: Calculate the multi-point synchronization deviation index, which measures the accuracy of synchronous control, based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. Specifically, the multi-point synchronization deviation index, which measures the accuracy of synchronous control, includes: ,in, For a moment Multi-point synchronization deviation index For a moment No. The load proportion weight of each apex point For a moment No. The actual cumulative lifting displacement of each lifting point For a moment Displacement via PLC commands issued by the PLC To avoid decimal division by zero, 0.10 mm can be used. This represents the total number of lifting points of the hydraulic jacks for the entire bridge.

[0034] Step 105: The differential jacking attitude deviation index, the traffic-jacking coupling stress safety reserve index, and the multi-point synchronization deviation index are integrated into a comprehensive real-time early warning index. Specifically, the calculation of the comprehensive real-time early warning index includes: ,in, For a moment Comprehensive real-time early warning index, For a moment The ratio of the differential lifting attitude deviation index to the updated threshold. For a moment The ratio of the target safety reserve design value to the traffic-lift coupling stress safety reserve index. For a moment The ratio of the multi-point synchronization deviation index to the preset synchronization deviation threshold. As the first weight, As the second weight, As the third weight, for and The positive coupling correction coefficient between them can be taken as... , This demonstrates that when attitude deviation and stress safety reserve deteriorate simultaneously, the combined risk of both is greater than the sum of their individual effects. For a moment Fatigue accumulation correction factor.

[0035] Preferred weighting coefficient , , Coupling correction coefficient with positive value The following positive definiteness conditions must be met: , , ,and To ensure that at all times Comprehensive Real-time Early Warning Index It is always non-negative.

[0036] Preferably, the calculation of the updated threshold includes: ,in, For a moment Updated threshold For the initial design threshold (initial design threshold) Can be taken rad (i.e., a difference displacement of 0.30 mm corresponding to 1000 mm degrees). This is the threshold tightening sensitivity coefficient, and its value range can be... , Design value for target safety reserve. From the start of the lifting operation to the moment The observed historical minimum traffic-lift coupling stress safety reserve index, when At that time, the threshold remains unchanged from its initial value.

[0037] Specifically, calculating the time Fatigue accumulation correction factor include: ,in, For fatigue damage weighting, an example value is given: for short-term lifting operations (duration not exceeding 7 days), the following values ​​are used: Standard jacking operation (7 to 30 days) Long-term jacking operations (more than 30 days) , From the start of the lifting operation to the moment The cumulative stress cycle number of the critical section, The design fatigue life cycle count for critical cross-sections. As the fatigue accumulation rate index, we can take... .

[0038] Step 106: Compare the comprehensive real-time early warning index with the multi-level early warning thresholds to determine the early warning level and trigger corresponding response measures.

[0039] Specifically, determining the warning level and triggering corresponding response measures includes: When the comprehensive real-time early warning index is less than the first early warning threshold (for example, it could be 0.40), it is determined to be in a normal state, and the current lifting rate is maintained to continue the operation; When the comprehensive real-time early warning index is greater than or equal to the first early warning threshold and less than the second early warning threshold (for example, it could be 0.70), it is judged as a level three early warning, triggering an audible and visual alarm and reducing the lifting rate to less than 50% of the normal rate; When the comprehensive real-time early warning index is greater than or equal to the second early warning threshold and less than the third early warning threshold (for example, it could be 1.00), it is judged as a level two early warning, the jacking operation is suspended and new vehicles are prohibited from entering the jacking section; When the comprehensive real-time early warning index is greater than or equal to the third early warning threshold, it is determined to be a first-level early warning. The jacking is stopped immediately and all hydraulic jacks are switched to the hydraulic and mechanical dual self-locking state.

[0040] Specifically, it also includes: when the first-level early warning condition is met for M consecutive main sampling times, an emergency stop command is automatically sent to the PLC main controller; When the comprehensive real-time early warning index does not meet the conditions for a Level 1 early warning, if any one of the differential jacking attitude deviation index, traffic-jacking coupling stress safety reserve index, and multi-point synchronization deviation index exceeds the corresponding single trigger threshold, a Level 2 early warning will be directly triggered, and corresponding response measures will be initiated.

[0041] Example 2 like Figure 2 As shown, this embodiment proposes a real-time early warning system for bridge jacking safety under traffic maintenance conditions, including: The data acquisition module is used to build a multi-source monitoring sensor network in the bridge jacking construction area, and to collect and preprocess the data from each sensor in time synchronization to obtain synchronous sensor data. The first calculation module is used to calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points, based on the real-time lifting displacement of each lifting point in the synchronous sensor data. The second calculation module is used to calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of the key section under the combined action of traffic live load and jacking load, based on the real-time traffic load and key section monitoring stress in the synchronous sensor data. The third calculation module is used to calculate the multi-point synchronization deviation index, which measures the accuracy of synchronous control, based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. The fourth calculation module is used to integrate the differential lifting attitude deviation index, the traffic-lifting coupling stress safety reserve index, and the multi-point synchronization deviation index into a comprehensive real-time early warning index; The early warning module is used to compare the comprehensive real-time early warning index with multi-level early warning thresholds, determine the early warning level, and trigger corresponding response measures.

[0042] Since Example 2 is based on Example 1, it will not be described again.

[0043] Example 3 This invention also proposes a storage medium storing multiple instructions, which are used to implement the aforementioned method for real-time early warning of bridge jacking safety under traffic maintenance conditions.

[0044] Optionally, in this embodiment, the storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals.

[0045] Optionally, in this embodiment, the storage medium is configured to store program code for performing the method steps of Embodiment 1.

[0046] Example 4 This invention also proposes an electronic device, including a processor and a storage medium connected to the processor. The storage medium stores multiple instructions, which can be loaded and executed by the processor to enable the processor to execute the aforementioned method for real-time early warning of bridge jacking safety under traffic maintenance conditions.

[0047] Specifically, the electronic device in this embodiment can be a computer terminal, which may include one or more processors and a storage medium.

[0048] The storage medium can be used to store software programs and modules, such as the real-time early warning method for bridge jacking safety under traffic maintenance conditions in this embodiment of the invention. The corresponding program instructions / modules allow the processor to execute various functional applications and data processing by running the software programs and modules stored in the storage medium, thus realizing the aforementioned real-time early warning method for bridge jacking safety under traffic maintenance conditions. The storage medium may include high-speed random access storage media, and may also include non-volatile storage media, such as one or more magnetic storage systems, flash memory, or other non-volatile solid-state storage media. In some instances, the storage medium may further include storage media remotely configured relative to the processor, which can be connected to the terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0049] The processor can execute the method steps of Embodiment 1 by calling the information and application stored in the storage medium through the transmission system.

[0050] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0051] In the several embodiments provided by this invention, it should be understood that the disclosed technical content can be implemented in other ways. The system embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between units or modules, and may be electrical or other forms.

[0052] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0053] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0054] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, optical disks, and other media capable of storing program code.

[0055] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A real-time early warning method for bridge jacking safety under traffic maintenance conditions, characterized in that, include: A multi-source monitoring sensor network was constructed within the bridge jacking construction area to collect and preprocess data from various sensors in real time, thereby obtaining synchronous sensor data. Based on the real-time lifting displacement of each lifting point in the synchronous sensor data, calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points; Based on real-time traffic load and critical section monitoring stress from synchronous sensor data, calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of critical sections under the combined action of traffic live load and jacking load. The multi-point synchronization deviation index, which measures the accuracy of synchronous control, is calculated based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. The differential lifting attitude deviation index, the traffic-lifting coupling stress safety reserve index, and the multi-point synchronization deviation index are integrated into a comprehensive real-time early warning index. The comprehensive real-time early warning index is compared with the multi-level early warning thresholds to determine the early warning level and trigger corresponding response measures.

2. The method for real-time safety early warning of bridge jacking under traffic maintenance conditions as described in claim 1, characterized in that, The calculation of the lifting attitude deviation index, which reflects the difference in spatial attitude consistency at the entire bridge lifting point, includes: in, For a moment The difference in the lifting attitude deviation index. This represents the total number of lifting points of the hydraulic jacks across the entire bridge. For a moment No. The cumulative lifting displacement of each apex point For a moment No. The cumulative lifting displacement of each apex point For the first The first peak point and the first The horizontal projection distance between each apex point For the first The first peak point and the first The structural stiffness weighting coefficient between the corresponding beam segments at each jacking point.

3. The method for real-time safety early warning of bridge jacking under traffic maintenance conditions as described in claim 1, characterized in that, The traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of critical sections under the combined action of traffic live load and jacking load, includes: in, For a moment The traffic-lift coupling stress safety reserve index For a moment Residual allowable stress at critical sections, For a moment The static stress generated by the lifting load at the critical section, For a moment The root mean square value of dynamic stress generated by traffic live loads at critical sections. For a moment Traffic dynamic amplification factor.

4. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 3, characterized in that, Calculation time Traffic dynamic amplification factor include: in, The roughness influence coefficient of the bridge deck surface. For a moment The average speed of passing vehicles It is the acceleration due to gravity. The calculated span of the lifting beam segment, This is the axle load sensitivity coefficient. For a moment The average equivalent axle load of passing vehicles For reference axle load.

5. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 1, characterized in that, The calculation of the multi-point synchronization deviation index, which measures the accuracy of synchronous control, includes: in, For a moment Multi-point synchronization deviation index For a moment No. The load proportion weight of each apex point For a moment No. The actual cumulative lifting displacement of each lifting point For a moment Displacement via PLC commands issued by the PLC For numerical stability parameters, This represents the total number of lifting points of the hydraulic jacks for the entire bridge.

6. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 1, characterized in that, The calculation of the comprehensive real-time early warning index includes: in, For a moment Comprehensive real-time early warning index, For a moment The ratio of the differential lifting attitude deviation index to the updated threshold. For a moment The ratio of the target safety reserve design value to the traffic-lift coupling stress safety reserve index. For a moment The ratio of the multi-point synchronization deviation index to the preset synchronization deviation threshold. As the first weight, As the second weight, As the third weight, for and Positive coupling correction coefficient between them For a moment Fatigue accumulation correction factor.

7. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 6, characterized in that, Calculation time Fatigue accumulation correction factor include: in, For fatigue damage weighting, From the start of the lifting operation to the moment The cumulative stress cycle number of the critical section, The design fatigue life cycle count for critical cross-sections. This is the fatigue accumulation rate index.

8. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 1, characterized in that, Determining the warning level and triggering corresponding response measures includes: When the comprehensive real-time early warning index is less than the first early warning threshold, it is determined to be a normal state, and the current lifting rate is maintained to continue the operation; When the comprehensive real-time early warning index is greater than or equal to the first early warning threshold and less than the second early warning threshold, it is judged as a level three early warning, triggering an audible and visual alarm and reducing the lifting rate to less than 50% of the normal rate; When the comprehensive real-time early warning index is greater than or equal to the second early warning threshold and less than the third early warning threshold, it is judged as a level two early warning, the jacking operation is suspended and new vehicles are prohibited from entering the jacking section; When the comprehensive real-time early warning index is greater than or equal to the third early warning threshold, it is determined to be a first-level early warning. The jacking is stopped immediately and all hydraulic jacks are switched to the hydraulic and mechanical dual self-locking state.

9. A real-time early warning method for bridge jacking safety under traffic maintenance conditions as described in claim 8, characterized in that, Also includes: When the first-level early warning condition is met for M consecutive main sampling times, an emergency stop command is automatically sent to the PLC main controller. When the comprehensive real-time early warning index does not meet the conditions for a Level 1 early warning, if any one of the differential jacking attitude deviation index, traffic-jacking coupling stress safety reserve index, and multi-point synchronization deviation index exceeds the corresponding single trigger threshold, a Level 2 early warning will be directly triggered, and corresponding response measures will be initiated.

10. A real-time early warning system for bridge jacking safety under traffic maintenance conditions, characterized in that, include: The data acquisition module is used to build a multi-source monitoring sensor network in the bridge jacking construction area, and to collect and preprocess the data from each sensor in time synchronization to obtain synchronous sensor data. The first calculation module is used to calculate the differential lifting attitude deviation index, which reflects the consistency of the spatial attitude of the entire bridge lifting points, based on the real-time lifting displacement of each lifting point in the synchronous sensor data. The second calculation module is used to calculate the traffic-lifting coupled stress safety reserve index, which reflects the stress safety margin of the key section under the combined action of traffic live load and jacking load, based on the real-time traffic load and key section monitoring stress in the synchronous sensor data. The third calculation module is used to calculate the multi-point synchronization deviation index, which measures the accuracy of synchronous control, based on the deviation between the real-time lifting displacement of each lifting point and the displacement commanded by the PLC. The fourth calculation module is used to integrate the differential lifting attitude deviation index, the traffic-lifting coupling stress safety reserve index, and the multi-point synchronization deviation index into a comprehensive real-time early warning index; The early warning module is used to compare the comprehensive real-time early warning index with multi-level early warning thresholds, determine the early warning level, and trigger corresponding response measures.

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