Bridge vehicle load inversion method and system based on dynamic deflection

Abstract

The invention discloses a bridge vehicle load inversion method and system based on dynamic deflection, and the method comprises the following steps: constructing a bridge information database which stores bridge structure type information, vehicle actuation deflection variation amplitudes, vehicle load data, and probability arrays of vehicle load data corresponding to different vehicle actuation deflection variation amplitudes; reading to-be-inverted dynamic deflection monitoring data, and calculating the change amplitude of the vehicle actuating deflection of the to-be-inverted dynamic deflection monitoring data; reading corresponding vehicle load data and a probability array according to the current bridge type information and the vehicle actuation deflection variation amplitude of the dynamic deflection monitoring data to be inverted; and taking the probability of the vehicle load data as a weight, determining an interval in which the vehicle load is located by adopting weighted sampling, and determining the vehicle load of the dynamic deflection monitoring data to be inversed in the interval by adopting simple random sampling. According to the method, the importance evaluation value of the influence of the vehicle on the crack is further constructed based on the vehicle actuation deflection change amplitude, the crack development is tracked and positioned, and the vehicle load effect evaluation is realized.

Description

Technical Field

[0001] The present application relates to the technical field of bridge health monitoring and performance evaluation, and in particular to a bridge vehicle load inversion method and system based on dynamic deflection. Background Art

[0002] The dynamic deflection data of bridges is real-time and instantaneous, and its changes are closely related to vehicle loads and crack development. Existing technologies require load tests to capture bridge dynamic deflection monitoring data. The obtained bridge dynamic deflection monitoring data are mostly used to derive its modal characteristics and dynamic characteristics. The core purpose is to analyze the intrinsic mechanical characteristics of the bridge structure through dynamic response data to evaluate the health of the bridge, but the existing technology has not yet been applied to invert vehicle loads based on dynamic deflection data. Secondly, large-scale and widespread national and provincial highway bridges are generally equipped with dynamic deflection monitoring projects, while other monitoring items are relatively few, especially the layout of dynamic weighing systems, which is not very common, resulting in a serious lack of vehicle load information for the corresponding national and provincial highway bridges. Therefore, the application scope of bridge dynamic deflection data still needs to be expanded to further explore the information contained in the data.

[0003] Secondly, in the study of crack development, existing technologies mostly obtain crack parameters through inspection and monitoring means, and combine the crack parameters with the stress in the nearby area for correlation analysis to locate potential damaged areas and reveal the crack development mechanism. In the case of less crack data obtained through manual detection and no stress data, it is impossible to effectively monitor the crack development. Summary of the invention

[0004] In view of the fact that the dynamic weighing system on national and provincial roads is not widely installed due to factors such as cost, resulting in a lack of vehicle load information, this application proposes a bridge vehicle load inversion method and system based on dynamic deflection, which takes the probability array of bridges with similar structural characteristics as a priori conditions, uses dynamic deflection data as input, performs vehicle load inversion, and can quickly evaluate vehicle load conditions and their impact on cracks.

[0005] In a first aspect, the present application provides a bridge vehicle load inversion method based on dynamic deflection, comprising the following contents: Constructing a bridge information database; the bridge information database stores bridge structure type information, dynamic deflection monitoring data, vehicle-actuated deflection variation amplitude, vehicle load data, vehicle-actuated deflection variation amplitude interval, vehicle load interval, and a probability array of vehicle load intervals corresponding to different vehicle-actuated deflection variation amplitude intervals; Reading the dynamic deflection monitoring data to be inverted, calculating the vehicle actuation deflection change amplitude of the dynamic deflection monitoring data to be inverted, and determining the vehicle actuation deflection change amplitude interval in which the vehicle actuation deflection change amplitude lies; According to the current bridge type information and the vehicle-driven deflection variation range of the dynamic deflection monitoring data to be inverted, a probability array of multiple vehicle load ranges corresponding to the range is extracted from the bridge information database; According to the extracted vehicle load range and its probability array, the weighted sampling method is used to determine the vehicle load range of the dynamic deflection monitoring data to be inverted, and simple random sampling is used within the vehicle load range to determine the vehicle load corresponding to the dynamic deflection monitoring data to be inverted.

[0006] In a possible implementation manner of the first aspect, the specific process of building the bridge information database is as follows: Collect information on bridge structure types, and collect dynamic deflection monitoring data and corresponding vehicle load data of bridges with different structural types; Calculating the vehicle actuation deflection variation amplitude according to the dynamic deflection monitoring data, performing probability calculation on the vehicle actuation deflection variation amplitude and vehicle load data, and obtaining the probability of vehicle load data corresponding to different vehicle actuation deflection variation amplitudes; Dividing the vehicle actuation deflection variation range and the vehicle load range, and determining a probability array of different vehicle actuation deflection variation ranges corresponding to different vehicle load ranges; A bridge information database is established based on bridge structure type information, dynamic deflection monitoring data, vehicle-induced deflection variation, vehicle load data, vehicle-induced deflection variation range, vehicle load range, and a probability array of vehicle load ranges corresponding to different vehicle-induced deflection variation ranges.

[0007] In a possible implementation manner of the first aspect, the method further includes the following step of calculating an importance evaluation value of the impact of the vehicle on the crack: Add the change amplitudes of the vehicle actuation deflection to obtain the cumulative value of the change amplitude of the vehicle actuation deflection in the corresponding time period; Determine the location of the crack to be evaluated based on the growth rate of the cumulative value of the change amplitude of the vehicle actuation deflection and the sensor location; Assume that the period before and after the crack to be evaluated is [t 1 , t 2 ], calculate [t 1 , t 2 ] Standard value of the width of the crack to be evaluated within the period: ; a 1 Indicates t 1 The crack width at time a 2 Indicates t 2 The crack width at the moment, indicates [t 1 , t 2 ] standard value of crack width within the time period; Calculate the standard value of the cumulative change in vehicle-actuated deflection before and after the crack develops: ; b means [t 1 , t 2 ], d represents the cumulative value of the change in the vehicle's actuation deflection during the period [t 1 , t 2 ] The amount of change in the vehicle's actuation deflection during the period, b 1 indicates [t 1 , t 2 The minimum change of the vehicle actuation deflection during the period, b 2 indicates [t 1 , t 2 ] the maximum change of the vehicle's actuation deflection during the period, indicates [t 1 , t 2 ] standard value of the cumulative value of the change in the vehicle's actuation deflection within the time period; Calculate the importance assessment of the vehicle's impact on the crack: ; ; m represents the importance assessment value of the impact of the vehicle on the crack, which is used to characterize the degree of impact of the vehicle on the crack; c represents the crack position correction coefficient, represents the maximum value of the load effect within the span, Indicates the maximum value of the load effect at the crack.

[0008] Optionally, the crack position correction coefficient is determined by a vehicle load test, or by simulating the load effect of a vehicle load obtained by inversion.

[0009] In a possible implementation manner of the first aspect, the following vehicle load effect evaluation step is also included: It is used to sort the importance evaluation values ​​and judge the degree to which the crack is affected by the vehicle according to the importance evaluation values.

[0010] In a possible implementation manner of the first aspect, the variation amplitude of the vehicle actuation deflection is calculated by the following method: Intercepting a deflection time history curve interval containing a plurality of troughs; preferably, the number of troughs in the deflection time history curve interval is not less than 3; Find and mark the valleys in the deflection time history curve, and record them as valley value 1, valley value 2, ..., valley value n; Taking the valley value i as the starting point, i∈[1,n], extend along the left and right of the deflection time history curve respectively until a lower valley value appears or reaches the end point of the deflection time history curve, forming a left and right interval segment starting from the valley value i; Find the maximum values ​​max_l and max_r of each interval in the left and right interval segments; Take the smaller value between the two maximum values ​​max_l and max_r, and the difference between the valley value i and the smaller value is the variation amplitude of the vehicle actuation deflection.

[0011] In a second aspect, the present application provides a system for executing the bridge vehicle load inversion method, comprising: A database construction module, constructs a bridge information database according to bridge structure type information, dynamic deflection monitoring data, vehicle-induced deflection variation range, vehicle load data, vehicle-induced deflection variation range interval, vehicle load range, and a probability array of vehicle load ranges corresponding to different vehicle-induced deflection variation range intervals; A vehicle actuation deflection variation amplitude calculation module is used to read the dynamic deflection monitoring data to be inverted, calculate the vehicle actuation deflection variation amplitude of the dynamic deflection monitoring data to be inverted, and determine the vehicle actuation deflection variation amplitude interval in which the vehicle actuation deflection variation amplitude lies; A vehicle load probability extraction module extracts a probability array of multiple vehicle load intervals corresponding to the interval from the bridge information database according to the current bridge type information and the vehicle-driven deflection change amplitude interval of the dynamic deflection monitoring data to be inverted; The vehicle load inversion module determines the vehicle load interval of the dynamic deflection monitoring data to be inverted based on the read vehicle load interval and its probability array, using the probability of each vehicle load interval as the weight and adopting a weighted sampling method. Simple random sampling is used within the vehicle load interval to determine the vehicle load corresponding to the dynamic deflection monitoring data to be inverted.

[0012] In a possible implementation manner of the second aspect, the method further includes: The vehicle actuation deflection accumulation module is used to add the change amplitudes of the vehicle actuation deflection to obtain the accumulated value of the change amplitude of the vehicle actuation deflection in the corresponding time period; A crack monitoring module determines the location of the crack to be evaluated according to the growth rate of the cumulative value of the vehicle actuation deflection change amplitude and the sensor position; The importance evaluation value calculation module is used to calculate the standard value of crack width and the standard value of the cumulative value of vehicle-actuated deflection change amplitude, and calculate the importance evaluation value of the vehicle's impact on the crack based on the standard value of crack width, the standard value of the cumulative value of vehicle-actuated deflection change amplitude and the crack position correction coefficient.

[0013] In a possible implementation manner of the second aspect, the method further includes: The importance evaluation module is used to sort the importance evaluation values ​​and determine the degree to which the crack is affected by the vehicle according to the importance evaluation values.

[0014] Compared with the existing methods, the present application can invert the vehicle load based on the dynamic deflection monitoring data, and further construct the importance evaluation index of the vehicle's impact on the crack, so as to track and locate the development of the crack; specifically, the present application has the following beneficial effects: 1. The deflection change amplitude is determined by locating the deflection trough and taking an interval on each side, which can adapt to dynamic deflection waveforms of various characteristics. All fluctuation amplitudes included in the dynamic deflection time history curve will not be repeatedly calculated or omitted; 2. The divided vehicle-induced deflection change amplitude interval is used as the prior condition of the interval of the vehicle-induced deflection change amplitude data in the inversion stage. According to the probability array of bridges with similar structural characteristics, the dynamic deflection data is used as input to perform vehicle load inversion. The inversion process has low calculation amount and greatly improves the operation speed. For national and provincial road bridges with existing dynamic deflection monitoring points but few other monitoring items, vehicle load inversion and rapid assessment of vehicle load impact can be achieved directly based on dynamic deflection monitoring data, which has broad application scenario support and corresponding potential; 3. The vehicle-actuated deflection variation amplitude collected by each sensor is accumulated, and according to the time period and sensor location when the accumulated value of the vehicle-actuated deflection variation amplitude increases rapidly, manual operation and maintenance activities such as nearby crack detection are guided to improve the detection accuracy and pertinence; 4. An evaluation index of the importance of vehicle impact on cracks was constructed, the impact of vehicle load on cracks was quantified, and the distribution evaluation of vehicle load impact was realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A flow chart of a bridge vehicle load inversion method based on dynamic deflection provided in an embodiment of the present application; Figure 2 A schematic diagram of the corresponding relationship between a vehicle-induced deflection variation range, a vehicle weight range and a probability provided in an embodiment of the present application; Figure 3 A schematic diagram of the change amplitude of vehicle actuation deflection caused by vehicle load in a deflection time course provided in an embodiment of the present application; Figure 4 A schematic diagram of a bridge vehicle load inversion result provided in an embodiment of the present application; Figure 5 A curve chart of crack monitoring data of the bottom of the left box girder during a period of rapid growth of the cumulative value of the change amplitude of the vehicle-actuated deflection provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0017] It should be clear that the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0018] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0019] First, as Figure 1 As shown in FIG. 1 , a bridge vehicle load inversion method based on dynamic deflection includes the following contents: S1, constructing a bridge information database, the database storing bridge structure type information, dynamic deflection monitoring data, vehicle-driven deflection variation amplitude, vehicle load data, vehicle-driven deflection variation amplitude interval, vehicle load interval, and probability array of vehicle load intervals corresponding to different vehicle-driven deflection variation amplitude intervals; S2, reading the dynamic deflection monitoring data to be inverted, calculating the vehicle actuation deflection change amplitude of the dynamic deflection monitoring data to be inverted, and determining the vehicle actuation deflection change amplitude interval in which the vehicle actuation deflection change amplitude lies; S3, extracting a probability array of multiple vehicle load intervals corresponding to the interval from the bridge information database according to the current bridge type information and the vehicle-induced deflection change amplitude interval of the dynamic deflection monitoring data to be inverted; S4, based on the extracted vehicle load interval and its probability array, taking the probability of each vehicle load interval as the weight, a weighted sampling method is adopted to determine the vehicle load interval of the dynamic deflection monitoring data to be inverted, and simple random sampling is used within the vehicle load interval to determine the vehicle load corresponding to the dynamic deflection monitoring data to be inverted.

[0020] In a possible implementation manner of the first aspect, the specific process of step S1 is as follows: S101, collecting structural information such as bridge span and cross-section, and collecting dynamic deflection time history of bridges of different structural types and vehicle load data of corresponding time periods; S102, reading the dynamic deflection monitoring data of different time periods in the dynamic deflection time course, calculating the vehicle actuation deflection change amplitude according to the dynamic deflection monitoring data, performing probability calculation on the vehicle actuation deflection change amplitude and vehicle load data, and obtaining the probability of vehicle load data corresponding to different vehicle actuation deflection change amplitudes; S103, dividing the vehicle actuation deflection variation range and the vehicle load range, and determining a probability array of different vehicle actuation deflection variation ranges corresponding to different vehicle load ranges; Figure 2As shown, a certain vehicle actuation deflection change range corresponds to multiple vehicle load ranges (in a horizontal row), and the sum of the probabilities of each vehicle load range is 1; S104, storing the bridge structure type information, dynamic deflection monitoring data, vehicle-induced deflection change amplitude, vehicle load data, vehicle-induced deflection change amplitude interval, vehicle load interval, and the probability array of vehicle load intervals corresponding to different vehicle-induced deflection change amplitude intervals into a database to establish a bridge information database; preferably, the bridge structure type information, deflection information, vehicle load information, etc. in the database should be updated regularly.

[0021] In a possible implementation of the first aspect, the bridge vehicle load inversion method based on dynamic deflection further includes the following steps: S5, reading the dynamic deflection monitoring data collected by the sensor, calculating the change amplitude of the vehicle actuation deflection, and accumulating the change amplitude of the vehicle actuation deflection to obtain the accumulated value of the change amplitude of the vehicle actuation deflection; S6, monitoring the period when the cumulative value of the change amplitude of the actuation deflection of the vehicle increases rapidly, determining the position of the crack to be evaluated according to the position of the sensor, and extracting the crack monitoring data in this period; S7, calculating the importance assessment value of the vehicle's influence on the crack according to the standard value of the crack width, the standard value of the cumulative value of the vehicle's actuated deflection change amplitude, and the crack position correction coefficient.

[0022] Specifically, assuming that the period during which the cumulative value of the vehicle's actuation deflection changes rapidly increases is [t 1 , t 2 ], according to [t 1 , t 2 ] crack monitoring data during the period, and calculate the importance assessment value of the impact of vehicles on cracks during the period: (1) Calculate the standard value of the crack width to be evaluated: ; a 1 represents the previous value of the crack width, i.e. t 1 The crack width at time a 2 Indicates the crack width value, that is, t 2 The crack width at the moment, indicates [t 1 , t 2 ] standard value of crack width within the time period; (2) Calculate [t 1 , t 2 ] Standard value of the cumulative value of the vehicle's actuation deflection change within the period : ; b represents the cumulative value of the change in vehicle-driven deflection before and after the crack develops, and d represents [t1 , t 2 ] The amount of change in the vehicle's actuation deflection during the period, b 1 indicates [t 1 , t 2 The minimum change of the vehicle actuation deflection during the period, b 2 indicates [t 1 , t 2 ] the maximum change of the vehicle's actuation deflection during the period, indicates [t 1 , t 2 ] standard value of the cumulative value of the change in the vehicle's actuation deflection within the time period; (3) Calculate [t 1 , t 2 ]The importance assessment value m of the impact of vehicles on cracks during the period: ; ; The importance assessment value m of the vehicle's impact on the crack is used to characterize the degree of impact of the vehicle on the crack; c represents the crack position correction coefficient, which is determined by a vehicle load test or by a simulated load effect of a vehicle load obtained by inversion. represents the maximum value of the load effect within the span, Indicates the maximum value of the load effect at the crack.

[0023] Furthermore, the bridge vehicle load inversion method based on dynamic deflection also includes the following steps: The importance assessment values ​​are ranked. The larger the importance assessment value, the greater the impact of the crack on the vehicle. Therefore, cracks with larger assessment values ​​should be reinforced in a timely manner.

[0024] like Figure 3 As shown, in the deflection time history (deflection is negative), the vehicle load will cause different degrees of dynamic deflection changes, and this application defines this change as the vehicle-actuated deflection change amplitude. This application preferably uses the following method to calculate the vehicle-actuated deflection change amplitude: Intercepting a deflection time history curve interval containing a plurality of troughs; preferably, the number of troughs is at least three; Find and mark the valleys in the deflection time history curve, recording them as valley value 1, valley value 2, ... valley value n; Taking the valley value i as the starting point, i∈[1,n], extend along the left and right of the deflection time history curve respectively until a lower valley value appears or reaches the end point of the deflection time history curve, forming a left and right interval segment starting from the valley value i; Find the maximum values ​​max_l and max_r of each interval in the left and right interval segments, where the maximum values ​​max_l and max_r are the peaks or the endpoints of the deflection time history curve in the left and right interval segments; specifically, there are 8 cases as follows: (1) If the valley value i is higher than the valley value i-1 on the left and the valley value i+1 on the right, extend the valley value i to the left to the valley value i-1 to form a left interval segment, and extend the valley value i to the right to the valley value i+1 to form a right interval segment. Take the maximum values ​​max_l1 and max_r1 of the left and right interval segments respectively; (2) If the left side of valley value i is the endpoint of the deflection time history curve, and valley value i is higher than valley value i+1 on the right side, extend from valley value i to the left to the left endpoint of the deflection time history curve to form a left interval segment, and extend from valley value i to the right to valley value i+1 to form a right interval segment, and take the maximum values ​​max_l2 and max_r2 of the left and right interval segments respectively; (3) If the valley value i is lower than the peak value i-1 on the left, and the right side of the valley value i is the endpoint of the deflection time history curve, the left interval is formed by extending from the valley value i to the left to the valley value i-1, and the right interval is formed by extending from the valley value i to the right to the right endpoint of the deflection time history curve. The maximum values ​​of the left and right intervals, max_l3 and max_r3, are taken respectively; (4) If the valley value i is the lowest valley value in the deflection time history curve interval, extend leftward and rightward from the valley value i as the starting point until reaching the left and right end points of the deflection time history curve, forming a left and right interval segment with the valley value i as the starting point, and take the maximum values ​​max_l4 and max_r4 of the left and right interval segments respectively; (5) If the valley value i is lower than the valley value i-1 on the left, but higher than the valley value i+1 on the right, extend leftward from the valley value i to a lower valley value or the left end point of the deflection time history curve to form a left interval segment, and extend rightward from the valley value i to the valley value i+1 to form a right interval segment. Take the maximum values ​​max_l5 and max_r5 of the left and right interval segments respectively; (6) If the valley value i is higher than the valley value i-1 on the left, but lower than the valley value i+1 on the right, extend from the valley value i to the left to the valley value i-1 to form a left interval segment, and extend from the valley value i to the right to a lower valley value or the right end point of the deflection time history curve to form a right interval segment. Take the maximum values ​​of the left and right interval segments, max_l6 and max_r6, respectively; (7) If the valley value i is lower than the valley value i-1 on the left, and the right side of the valley value i is the endpoint of the deflection time-history curve, the valley value i is taken as the starting point and extends to the left to a lower valley value or the left endpoint of the deflection time-history curve to form a left interval segment. The valley value i is taken as the starting point and extends to the right to the right endpoint of the deflection time-history curve to form a right interval segment. The maximum values ​​of the left and right interval segments, max_l7 and max_r7, are taken respectively. (8) If the left side of valley value i is the endpoint of the deflection time-history curve, and valley value i is lower than valley value i+1 on the right side, extend from valley value i to the left to the left endpoint of the deflection time-history curve to form a left interval segment, and extend from valley value i to the right to a lower valley value or the right endpoint of the deflection time-history curve to form a right interval segment, and take the maximum values ​​of the left and right interval segments, max_l8 and max_r8, respectively; Take the smaller value between the two maximum values ​​max_l and max_r determined above, and the difference between the valley value i and the smaller value is the vehicle actuated deflection change amplitude; this method can accurately determine the numerical value and quantity of the vehicle actuated deflection change amplitude, and the vehicle actuated deflection change amplitude interval is determined based on the vehicle actuated deflection change amplitude vector element value, in which there may be multiple vehicle actuated deflection change amplitudes.

[0025] In a second aspect, the present application provides a system for executing the bridge vehicle load inversion method, comprising: A database construction module, which constructs a bridge information database according to bridge structure type information, dynamic deflection monitoring data, vehicle-driven deflection change amplitude, vehicle load data corresponding to the vehicle-driven deflection change amplitude and its probability array; A vehicle-actuated deflection variation amplitude calculation module is used to read the dynamic deflection monitoring data to be inverted and calculate the vehicle-actuated deflection variation amplitude of the dynamic deflection monitoring data to be inverted; A vehicle load probability extraction module reads the vehicle load data and its probability array corresponding to the vehicle-actuated deflection variation amplitude of the dynamic deflection monitoring data to be inverted from the bridge information database according to the current bridge type information and the vehicle-actuated deflection variation amplitude of the dynamic deflection monitoring data to be inverted; The vehicle load inversion module determines the vehicle load range of the dynamic deflection monitoring data to be inverted based on the read vehicle load data and its probability array, using the probability of each vehicle load data as the weight and adopting the weighted sampling method. The vehicle load corresponding to the dynamic deflection monitoring data to be inverted is determined by simple random sampling within the vehicle load range.

[0026] In a possible implementation manner of the second aspect, the system further includes: The vehicle actuation deflection accumulation module is used to add the change amplitudes of the vehicle actuation deflection to obtain the accumulated value of the change amplitude of the vehicle actuation deflection in the corresponding time period; A crack monitoring module determines the location of the crack to be evaluated according to the growth rate of the cumulative value of the vehicle actuation deflection change amplitude and the sensor position; The importance evaluation value calculation module is used to calculate the standard value of crack width and the standard value of the cumulative value of vehicle-actuated deflection change amplitude, and calculate the importance evaluation value of the vehicle's impact on the crack based on the standard value of crack width, the standard value of the cumulative value of vehicle-actuated deflection change amplitude and the crack position correction coefficient.

[0027] Furthermore, the system also includes: The importance assessment module is used to sort the importance assessment values, determine the degree to which the cracks are affected by the vehicle according to the importance assessment values, and perform reinforcement treatment on cracks with larger assessment values.

[0028] It should be understood that the division of the processing modules in the above system is only a division of logical functions, and in actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. In addition, the processing unit in the system can be implemented in the form of a processor calling software; for example, the system includes a processor, the processor is connected to a memory, and instructions are stored in the memory. The processor calls the instructions stored in the memory to implement any of the above methods or implement the functions of the processing units of the system, wherein the processor is a general-purpose processor, such as a central processing unit or a microprocessor, and the memory is a memory within the system or a memory outside the system.

[0029] The following is an example of the application of the vehicle load inversion method based on dynamic deflection monitoring to the G344 Baoying Canal Third Bridge (with a WIM system installed). Combined with this example, the feasibility and effectiveness of the present application are explained.

[0030] Calculate the probability array of vehicle load interval according to equations (1) to (4); (1); (2); (3); (4); Where d is the vehicle-actuated deflection change amplitude vector, l is the vehicle load vector, and the number of elements in d and l is m. The endpoint value vector of the vehicle-actuated deflection change amplitude interval is , the endpoint value vector of the vehicle load interval is ;con is the counting function; The probability of a vehicle load in the jth vehicle load interval obtained by inverting the change amplitude of a vehicle actuated deflection in the i-th vehicle actuated deflection range is: The first half of , Represents the element in the i-th row and j-th column of the inversion basis array; The probability of vehicle load is used as the weight and the inverted vehicle load is obtained through weighted sampling. The inversion result is as follows: Figure 4 As shown, the inverted total weight is 757.14t, the WIM measured total weight is 671.65t, and the inverted value / measured value (%) = 112.7%.

[0031] The corresponding left box girder bottom crack monitoring data for the bridge from 0:00 on January 20, 2025 to 0:00 on January 27, 2025 are as follows: Figure 5 shown.

[0032] (1) Calculation of standard crack width =0.435; (2) Calculate the standard value of the cumulative value of the vehicle's actuation deflection change =1.224; (3) Calculate the importance assessment value of the impact of the vehicle on the crack during this period =0.330, crack position correction factor =0.928; indicating that the crack is less affected by vehicle load.

[0033] Other structural type demonstration projects and inversion results are shown in Table 1.

[0034] Table 1 Inversion results of the demonstration project Bridge Name Route Number Main span (m) Daily heavy vehicle load (t) Inversion value / WIM measured value (%) Cailing Port Bridge G312 25 1783 97.0 Xiacheng Bridge G312 20 1624 93.7 Dongdatong River Bridge G312 30 1672 104.1 Xidatong River Bridge G312 30 1826 100.8 Yejiaqiao G312 20 1847 87.5 Polder Bridge G312 16 1437 98.2 Buyi River Bridge G312 75 1874 114.2 Houshu River Bridge G312 16 1863 108.0 Houshi Bridge G312 16 1646 110.5 Hexi River Bridge G312 16 1674 86.8 Yangjiaqiao G312 10 1784 103.4 Benniu South Interchange G312 30 1864 74.2 Xihe Bridge G312 10 1569 104.3 Baoying Lake Water Retreat Bridge G344 70 2186 85.5 Maoshan River Bridge (left) S231 40 1372 119.9 Table 2 shows the importance assessment values ​​of the impact of vehicles on cracks in the above-mentioned demonstration projects, which are concentrated in the range of 0.4~0.6. Among them, the importance assessment value of Dongdatong River Bridge is 0.877, and the surface cracks are most susceptible to vehicle loads.

[0035] Table 2 Evaluation value of the importance of the impact of vehicles on cracks in the demonstration project Bridge Name Importance Assessment Value Cailing Port Bridge 0.473 Xiacheng Bridge 0.548 Dongdatong River Bridge 0.877 Xidatong River Bridge 0.536 Yejiaqiao 0.545 Polder Bridge 0.521 Buyi River Bridge 0.127 Houshu River Bridge 0.437 Houshi Bridge 0.671 Hexi River Bridge 0.318 Yangjiaqiao 0.875 Benniu South Interchange 0.462 Xihe Bridge 0.461 Baoying Lake Water Retreat Bridge 0.599 Maoshan River Bridge (left) 0.674 It has been verified by engineering examples that the vehicle load inversion method of the present application is feasible and effective. In the vehicle load inversion method, the error rate between the inversion value and the WIM measured value is within 20%.

[0036] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A bridge vehicle load inversion method based on dynamic deflection, characterized in that: It includes the following: Constructing a bridge information database; the bridge information database stores bridge structure type information, dynamic deflection monitoring data, vehicle-actuated deflection variation amplitude, vehicle load data, vehicle-actuated deflection variation amplitude interval, vehicle load interval, and a probability array of vehicle load intervals corresponding to different vehicle-actuated deflection variation amplitude intervals; Reading the dynamic deflection monitoring data to be inverted, calculating the vehicle actuation deflection change amplitude of the dynamic deflection monitoring data to be inverted, and determining the vehicle actuation deflection change amplitude interval in which the vehicle actuation deflection change amplitude lies; According to the current bridge type information and the vehicle-driven deflection variation range of the dynamic deflection monitoring data to be inverted, a probability array of multiple vehicle load ranges corresponding to the range is extracted from the bridge information database; According to the extracted vehicle load range and its probability array, the weighted sampling method is used to determine the vehicle load range of the dynamic deflection monitoring data to be inverted, and simple random sampling is used within the vehicle load range to determine the vehicle load corresponding to the dynamic deflection monitoring data to be inverted.

2. The bridge vehicle load inversion method according to claim 1 is characterized in that: The specific process of constructing the bridge information database is as follows: Collect information on bridge structure types, and collect dynamic deflection monitoring data and corresponding vehicle load data of bridges with different structural types; Calculating the vehicle actuation deflection variation amplitude according to the dynamic deflection monitoring data, performing probability calculation on the vehicle actuation deflection variation amplitude and vehicle load data, and obtaining the probability of vehicle load data corresponding to different vehicle actuation deflection variation amplitudes; Dividing the vehicle actuation deflection variation range and the vehicle load range, and determining a probability array of different vehicle actuation deflection variation ranges corresponding to different vehicle load ranges; A bridge information database is established based on bridge structure type information, dynamic deflection monitoring data, vehicle-induced deflection variation, vehicle load data, vehicle-induced deflection variation range, vehicle load range, and a probability array of vehicle load ranges corresponding to different vehicle-induced deflection variation ranges.

3. The bridge vehicle load inversion method according to claim 1 is characterized in that: The step of calculating the importance assessment value of the vehicle's impact on the crack is also included: Add the change amplitudes of the vehicle actuation deflection to obtain the cumulative value of the change amplitude of the vehicle actuation deflection in the corresponding time period; Determine the location of the crack to be evaluated based on the growth rate of the cumulative value of the change amplitude of the vehicle actuation deflection and the sensor location; Assuming that the time period before and after the crack to be evaluated is [t1, t2], calculate the standard value of the width of the crack to be evaluated in the time period [t1, t2]: ； a1 represents the crack width at time t1, a2 represents the crack width at time t2, represents the standard value of crack width in the period [t1, t2]; Calculate the standard value of the cumulative change in vehicle-actuated deflection before and after the crack develops: ； b represents the cumulative value of the vehicle actuation deflection change in the period [t1, t2], d represents the number of vehicle actuation deflection change in the period [t1, t2], b1 represents the minimum value of the vehicle actuation deflection change in the period [t1, t2], b2 represents the maximum value of the vehicle actuation deflection change in the period [t1, t2], It represents the standard value of the cumulative change of the vehicle's actuation deflection during the period [t1, t2]; Calculate the importance assessment of the vehicle's impact on the crack: ； ； m represents the importance assessment value of the impact of the vehicle on the crack, which is used to characterize the degree of impact of the vehicle on the crack; c represents the crack position correction coefficient, represents the maximum value of the load effect within the span, Indicates the maximum value of the load effect at the crack.

4. The bridge vehicle load inversion method according to claim 3 is characterized in that: The crack position correction factor is determined by a vehicle load test.

5. The bridge vehicle load inversion method according to claim 3 is characterized in that: The crack position correction coefficient is determined by simulating the load effect of the vehicle load obtained by inversion.

6. The bridge vehicle load inversion method according to claim 3 is characterized in that: The following steps are included in the vehicle load effect assessment: It is used to sort the importance evaluation values ​​and judge the degree to which the crack is affected by the vehicle according to the importance evaluation values.

7. The bridge vehicle load inversion method according to claim 1 is characterized in that: The following method is used to calculate the variation of the vehicle actuation deflection: Intercepting the deflection time history curve interval containing multiple troughs; Find and mark the valleys in the deflection time history curve, and record them as valley value 1, valley value 2, ..., valley value n; Taking the valley value i as the starting point, i∈[1,n], extend along the left and right of the deflection time history curve respectively until a lower valley value appears or reaches the end point of the deflection time history curve, forming a left and right interval segment starting from the valley value i; Find the maximum values ​​max_l and max_r of each interval in the left and right interval segments; Take the smaller value between the two maximum values ​​max_l and max_r, and the difference between the valley value i and the smaller value is the variation amplitude of the vehicle actuation deflection.

8. A system for executing the bridge vehicle load inversion method according to any one of claims 1 to 7, characterized in that: include: A database construction module, constructs a bridge information database according to bridge structure type information, dynamic deflection monitoring data, vehicle-induced deflection variation range, vehicle load data, vehicle-induced deflection variation range interval, vehicle load range, and a probability array of vehicle load ranges corresponding to different vehicle-induced deflection variation range intervals; A vehicle actuation deflection variation amplitude calculation module is used to read the dynamic deflection monitoring data to be inverted, calculate the vehicle actuation deflection variation amplitude of the dynamic deflection monitoring data to be inverted, and determine the vehicle actuation deflection variation amplitude interval in which the vehicle actuation deflection variation amplitude lies; A vehicle load probability extraction module extracts a probability array of multiple vehicle load intervals corresponding to the interval from the bridge information database according to the current bridge type information and the vehicle-driven deflection change amplitude interval of the dynamic deflection monitoring data to be inverted; The vehicle load inversion module determines the vehicle load interval of the dynamic deflection monitoring data to be inverted based on the read vehicle load interval and its probability array, using the probability of each vehicle load interval as the weight and adopting a weighted sampling method. Simple random sampling is used within the vehicle load interval to determine the vehicle load corresponding to the dynamic deflection monitoring data to be inverted.

9. The system according to claim 8, characterized in that Also includes: The vehicle actuation deflection accumulation module is used to add the change amplitudes of the vehicle actuation deflection to obtain the accumulated value of the change amplitude of the vehicle actuation deflection in the corresponding time period; A crack monitoring module determines the location of the crack to be evaluated according to the growth rate of the cumulative value of the change amplitude of the vehicle actuation deflection and the sensor position; The importance evaluation value calculation module is used to calculate the standard value of crack width and the standard value of the cumulative value of vehicle-actuated deflection change amplitude, and calculate the importance evaluation value of the vehicle's impact on the crack based on the standard value of crack width, the standard value of the cumulative value of vehicle-actuated deflection change amplitude and the crack position correction coefficient.

10. The system according to claim 9, characterized in that Also includes: The importance evaluation module is used to sort the importance evaluation values ​​and determine the degree to which the crack is affected by the vehicle according to the importance evaluation values.

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