Internal stress measurement method and device applied to prestressed steel cable

Abstract

The invention discloses an internal stress measurement method and device applied to a prestressed steel cable, and relates to the technical field of stress measurement, and the method comprises the steps: obtaining stress measurement data of different measurement points on the prestressed steel cable; based on the stress measurement data and the influence degree of the external force on each measurement point, determining the stress non-uniformity degree of the prestressed steel cable; on the basis of the stress non-uniformity degree and the stress change consistency of the prestressed steel cables, the cooperative stress influence degree of the prestressed steel cables is obtained through calculation; the vibration influence degree of the overall structure is determined based on the cooperative stress influence degrees of the different prestress steel cables; based on the ratio of the cooperative stress influence degree to the overall structure vibration influence degree, the data acquisition accuracy of each prestressed steel cable is calculated; and correcting the stress measurement data based on the data acquisition accuracy and a preset neural network model. The technical effect of improving the accuracy of stress measurement data is achieved.

Description

Technical Field

[0001] This invention relates to the field of stress measurement technology, and specifically to a method and apparatus for measuring the internal stress of prestressed steel cables. Background Technology

[0002] Prestressed steel cables, as key load-bearing components, are widely used in the cables of cable-stayed bridges, the main cables of suspension bridges, the tendons of prestressed concrete structures, and slope anchorage systems in geotechnical engineering. Their internal stress (i.e., cable force) is a core parameter for assessing structural safety and service condition. The accuracy and stability of cable force not only affect structural stiffness and deformation control but also relate to long-term service safety.

[0003] During the internal stress measurement of prestressed steel cables, structural vibrations (such as vehicle traffic and wind effects) can cause the cables to be in a dynamic stress state, subjecting them to additional dynamic loads and resulting in insufficient measurement accuracy. Furthermore, the varying tension of the cables affects their ability to resist structural vibration deformation, thus impacting them differently. Additionally, since the cables form a mechanical whole through the steel structure, changes in the force on one cable can cause stress changes in other cables. Existing detection methods do not adequately consider the internal stress changes caused by structural vibrations, leading to insufficient accuracy in the collected data. Subsequent tensioning or adjustment of prestressed anchor cables may be inaccurate, affecting the safety of the cable structure. Summary of the Invention

[0004] To address the technical problem in related technologies that fail to adequately consider internal stress changes caused by structural vibration, resulting in insufficient accuracy of collected data and potentially inaccurate subsequent tensioning or adjustment of prestressed anchor cables, thus affecting the safety of cable structures, this invention provides a method and apparatus for measuring internal stress in prestressed cables.

[0005] The specific technical solution adopted is as follows: Obtain stress measurement data at different measurement points on the prestressed steel cable; Based on stress measurement data and the degree of influence of external forces at each measurement point, the degree of stress non-uniformity of the prestressed steel cable is determined. Based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed cable, the degree of influence of the coordinated stress on the prestressed cables is calculated. Based on the degree of synergistic stress influence of different prestressed steel cables, the degree of overall structural vibration influence of each prestressed steel cable corresponding to the structure is determined; Based on the ratio between the degree of influence of coordinated stress and the degree of influence of overall structural vibration, the data acquisition accuracy of each prestressed steel cable is calculated. Based on the accuracy of data acquisition and the preset neural network model, the stress measurement data is corrected to eliminate errors in the stress measurement data.

[0006] In one possible implementation of this application, the degree of stress non-uniformity in the prestressed steel cable is determined based on stress measurement data and the degree of influence of external forces at each measurement point, including: The preset stress value of the prestressed steel cable is determined, and the tension coefficient of the prestressed steel cable is calculated based on the difference between the average stress borne by the prestressed steel cable and the preset stress value in the stress measurement data. Based on the difference between the maximum value of the tension state coefficient and the tension state coefficient of each prestressed cable, the tension state influence coefficient of each prestressed cable is calculated. Based on the influence coefficient of tension and the stress difference between stress measurement data at different times, the vibration influence coefficient of different measurement points is calculated. Based on the fluctuation of the vibration influence coefficient at each measuring point on the prestressed steel cable, the degree of stress non-uniformity on each prestressed steel cable is calculated.

[0007] In one possible embodiment of this application, the tension state influence coefficient of each prestressed cable is calculated based on the difference between the maximum value of the tension state coefficient and the tension state coefficient of each prestressed cable, including: Determine the maximum value of the tension coefficient and the first difference between the tension coefficient of each prestressed cable; The influence coefficient of the tension state of each prestressed steel cable is calculated based on the reciprocal of the first difference.

[0008] In one possible implementation of this application, the vibration influence coefficient at different measurement points is calculated based on the tension / looseness influence coefficient and the stress difference between stress measurement data at different times, including: Determine the second difference between the stress measurement data at different times and the minimum value of the stress measurement data; The vibration influence coefficients at different measurement points are calculated by multiplying the average value of each second difference with the influence coefficient of the tightness / slack state.

[0009] In one possible embodiment of this application, based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed cable, the degree of cooperative stress influence of the prestressed cables is calculated, including: Based on the degree of stress non-uniformity and stress measurement data at different measurement points, the instantaneous vibration sensitivity of the prestressed steel cable at each measurement moment was determined. Based on the difference in instantaneous vibration sensitivity at different measurement times, the degree of cable undulation for each prestressed cable is calculated. Based on the difference between the degree of cable undulation and the average degree of cable undulation, the degree of consistency of stress change of each prestressed cable is calculated. The degree of influence of coordinated stress is calculated based on the product of stress non-uniformity and the degree of consistency of stress change.

[0010] In one possible implementation of this application, the degree of cable undulation for each prestressed cable is calculated based on the difference in instantaneous vibration sensitivity at different measurement times, including: For any prestressed cable, calculate the third difference in the instantaneous vibration sensitivity between adjacent measurement times of the current prestressed cable; The degree of cable fluctuation for each prestressed cable is calculated based on the sum of the third difference values ​​corresponding to each prestressed cable.

[0011] In one possible embodiment of this application, the degree of overall structural vibration impact of each prestressed cable is determined based on the degree of synergistic stress influence of different prestressed cables, including: Based on the sum of the synergistic stress influence of different prestressed steel cables, the overall structural vibration influence of each prestressed steel cable is determined.

[0012] In one possible implementation of this application, the data acquisition accuracy of each prestressed steel cable is calculated based on the ratio between the degree of influence of synergistic stress and the degree of influence of overall structural vibration, including: Calculate the first ratio between the degree of influence of the coordinated force and the degree of influence of the overall structural vibration; The data acquisition accuracy of each prestressed steel cable is calculated based on the normalized value of the difference between the preset value and the first ratio.

[0013] In one possible implementation of this application, stress measurement data is corrected based on data acquisition accuracy and a preset neural network model to eliminate errors in the stress measurement data, including: By fusing the data acquisition accuracy with the stress measurement data, a multidimensional feature matrix is ​​constructed. The pre-defined neural network model is iteratively trained using a multi-dimensional feature matrix to obtain the trained neural network model. The trained neural network model is used to predict and process stress measurement data, and output corrected stress data to eliminate errors in the stress measurement data.

[0014] To achieve the above objectives, an internal stress measuring device for prestressed steel cables is also provided, comprising: The acquisition module is used to acquire stress measurement data at different measurement points on the prestressed steel cable; The first determining module is used to determine the degree of stress non-uniformity of the prestressed steel cable based on stress measurement data and the degree of influence of external forces on each measurement point; The first calculation module is used to calculate the degree of collaborative stress influence of the prestressed steel cables based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed steel cable. The second determining module is used to determine the degree of overall structural vibration impact of each prestressed steel cable based on the degree of collaborative stress influence of different prestressed steel cables. The second calculation module is used to calculate the data acquisition accuracy of each prestressed steel cable based on the ratio between the degree of influence of collaborative stress and the degree of influence of overall structural vibration. The calibration module is used to calibrate stress measurement data based on the accuracy of data acquisition and a preset neural network model, in order to eliminate errors in the stress measurement data.

[0015] The present invention has, but is not limited to, the following technical effects: By acquiring stress measurement data at different measurement points on the prestressed steel cable, and based on the stress measurement data and the degree of influence of external forces on each measurement point, the stress non-uniformity of the prestressed steel cable is calculated. Based on the stress non-uniformity and the consistency of stress changes in each prestressed steel cable, the degree of collaborative force influence of the prestressed steel cable is calculated. Furthermore, based on the degree of collaborative force influence of different prestressed steel cables, the degree of overall structural vibration influence of each prestressed steel cable is calculated. Then, based on the degree of collaborative force influence and the degree of overall structural vibration influence, the data acquisition accuracy of the prestressed steel cable is calculated. Subsequently, the stress measurement data is corrected using a preset neural network model and the data acquisition accuracy, outputting more accurate corrected stress measurement data, thereby eliminating errors in the stress measurement data and improving measurement accuracy. Finally, based on the measurement data, adaptive adjustments are made to the prestressed anchor cable to improve the safety of the cable structure. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of the first embodiment of the internal stress measurement method for prestressed steel cables applied in this application; Figure 2 This is a schematic diagram of the overall implementation process of the internal stress measurement method for prestressed steel cables applied in this application; Figure 3 This is a schematic diagram of the device structure of the hardware operating environment involved in the embodiments of this application. Detailed Implementation

[0017] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0018] This application provides a method for measuring the internal stress of prestressed steel cables. In the first embodiment of this application's method for measuring the internal stress of prestressed steel cables, referring to... Figure 1 The methods include: Step S10: Obtain stress measurement data at different measurement points on the prestressed steel cable.

[0019] As an example, the method for measuring the internal stress of prestressed steel cables can be applied to an internal stress measuring device for prestressed steel cables. The internal stress measuring device for prestressed steel cables belongs to an internal stress measuring system for prestressed steel cables, and the internal stress measuring system for prestressed steel cables belongs to an internal stress measuring equipment for prestressed steel cables.

[0020] As an example, stress measurement data can be obtained by deploying stress sensing devices at multiple measurement points on a prestressed steel cable (hereinafter referred to as the cable) and then measuring the stress of the cable through these devices.

[0021] The measurement method can be: High-precision fiber optic grating sensors or magnetoelastic effect sensors are installed at the ends, mid-span, and other locations where stress concentration or external excitation may occur on the steel cables. At least five such sensors are installed on each steel cable. Assuming there are A steel cables in total, N data acquisition points (measurement points) are arranged on each cable. The control unit of the data acquisition module ensures that the timestamps of the sensors at different locations are consistent, and multiple sets of stress data are continuously acquired. The preset number of acquisitions is K, and each acquisition corresponds to an acquisition time.

[0022] As an example, the collected stress measurement data is preprocessed, including filtering, noise reduction, and data calibration. Based on the sensor calibration coefficients, the strain data is converted into corresponding stress values, forming a dataset of stress measurement data for the steel cable at different locations and times. For example, the k-th stress measurement data at the n-th measurement point of the a-th steel cable is denoted as... .

[0023] Step S20: Based on the stress measurement data and the degree of influence of external forces on each measurement point, determine the degree of stress non-uniformity of the prestressed steel cable.

[0024] As an example, during the measurement of the internal stress of prestressed steel cables, the vibration caused by vehicle traffic and wind forces puts the cables in a dynamic stress state, affecting the measurement of the internal stress. Furthermore, the varying tension of the cables affects their overall resistance to deformation. At different measurement points, the degree of vibration caused by external forces varies. During the measurement of the internal stress, the magnitude of the cable force alters the cable's equivalent stiffness. When the cable force exceeds the limit, the increased force provides additional "geometric stiffness," enhancing its overall resistance to deformation. When the cable tension is insufficient, the cable will appear "loose" and is more prone to large swaying and deformation under external loads. The degree of structural vibration varies depending on the tension (stress state) of the cable. Under normal conditions, the stress distribution of the cable is uniform, but external loads (such as wind or vehicle traffic) will cause the cable to vibrate, resulting in the cable bearing lateral loads. This amplifies the stress differences between the wires, and the internal stress distribution may become uneven due to vibration. Based on this, the stress non-uniformity of the prestressed cable is calculated. The stress non-uniformity is used to represent the stress distribution at different measurement points on the cable. The larger the value of the stress non-uniformity, the more uneven the stress distribution.

[0025] The step S20, which is applied to the internal stress measurement of prestressed steel cables, further includes steps S21 to S24, including: Step S21: Determine the preset stress value of the prestressed steel cable. Based on the difference between the average stress borne by the prestressed steel cable and the preset stress value in the stress measurement data, calculate the tension coefficient of the prestressed steel cable.

[0026] As an example, the tension of a steel cable varies, resulting in different geometric stiffnesses and thus different resistance to deformation. Each steel cable has a corresponding design force (stress) value, which is also the preset stress value. The greater the measured force exceeds the design force, the tighter the cable and the stronger its geometric stiffness. Conversely, the greater the measured force is less than the design force, the looser the cable. Based on this, a tension coefficient is calculated for the a-th steel cable. Taking the a-th cable as an example, the tension coefficient... The calculation method can be: In the formula, This represents the preset stress value of the a-th cable. The average stress at N measurement points of the a-th steel cable during K data collections is expressed by the following formula: Where N represents the total number of measurement points, and K represents the number of data collections. This represents the k-th stress measurement data at the n-th measurement point of the a-th steel cable. This value indicates the tension of the steel cable. A higher value indicates a looser cable with weaker resistance to vibration; a lower or negative value indicates a tighter cable (measured stress exceeding a preset value) and stronger geometric stiffness. When calculating tension, [further information is needed]. and All dimensions were eliminated in advance.

[0027] Step S22: Based on the maximum value of the tension state coefficient and the difference between the tension state coefficient of each prestressed cable, the tension state influence coefficient of each prestressed cable is calculated.

[0028] Step S22 includes: Determine the maximum value of the tension coefficient and the first difference between the tension coefficient of each prestressed cable.

[0029] The influence coefficient of the tension state of each prestressed steel cable is calculated based on the reciprocal of the first difference.

[0030] As an example, since geometric stiffness varies with cable force, high cable force means high geometric stiffness, so structural vibration has little effect on it and its sensitivity to vibration is low. Different cable tension states have different sensitivities to vibration. Therefore, the tension state influence coefficient is calculated by using the relative difference of tension state coefficient. The larger the value, the looser the cable is and the more sensitive it is to vibration.

[0031] As an example, taking the a-th steel cable as an example, the influence coefficient of tension state The calculation method can be: In the formula, This represents the maximum tension coefficient of cable A. This represents the tension coefficient of the a-th cable. This represents the first difference. Wherein, the first difference... The smaller, the better. The closer to the maximum value, the looser the cable is, indicating that the cable is more sensitive to vibration and its influence coefficient is higher. The larger.

[0032] Step S23: Based on the influence coefficient of the tightness state and the stress difference between stress measurement data at different times, the vibration influence coefficient of different measurement points is calculated.

[0033] As an example, the constraint strength varies at different measurement points on a steel cable. For instance, the constraint is stronger at both ends and weaker in the middle. Therefore, the degree of stress fluctuation caused by vibration may differ at different locations on the cable. Furthermore, the vibration impact on the cable stress varies at different times. Based on this, the vibration influence coefficient for different measurement points is calculated according to the difference between the stress measurement data at different times and the minimum stress measurement value. The vibration influence coefficient represents the degree of vibration impact on each measurement point; the larger the value, the more significant the vibration impact on the current measurement point.

[0034] Step S23 includes: Determine the second difference between the stress measurement data at different times and the minimum value of the stress measurement data.

[0035] The vibration influence coefficients at different measurement points are calculated by multiplying the average value of each second difference with the influence coefficient of the tightness / slack state.

[0036] As an example, taking the nth measurement point of the a-th steel cable as an example, the vibration influence coefficient... The calculation method can be: in, This represents the influence coefficient of the tension state of the a-th steel cable. Indicates the first Root steel cable The measurement point is the first The stress value measured in this test. Indicates the first Root steel cable Each measurement point is at The minimum stress value in the first acquisition. Indicates the second difference. and Dimensionless processing was performed before all calculations were performed.

[0037] Specifically, It reflects the range of stress change at the measurement point over time. The larger the value, the more violent the fluctuation, indicating that the measurement point is more significantly affected by vibration.

[0038] Step S24: Based on the fluctuation of the vibration influence coefficient at each measurement point on the prestressed steel cable, the degree of stress non-uniformity on each prestressed steel cable is calculated.

[0039] As an example, under normal circumstances, the internal force of a steel cable is evenly distributed at all locations. However, when subjected to lateral loads (such as wind or vibration), additional bending moments or shear forces are generated, which increases the stress difference of the steel wires at different locations within the cross section. Vibration amplifies the additional internal forces and the force transfer between the steel wires, leading to increased non-uniformity and increased data volatility. Therefore, the degree of stress non-uniformity of the steel cable is calculated based on the degree of fluctuation of the vibration influence coefficient at each measurement point.

[0040] As an example, taking the a-th steel cable as an example, the degree of stress non-uniformity... The calculation method can be: In the formula, Indicates the first Root steel cable Vibration influence coefficient at each measurement point Indicates the first The minimum vibration influence coefficient among N measurement points on the steel cable, where N represents the number of measurement points. This represents the cumulative sum of the deviations of each measurement point relative to the minimum influence coefficient. The larger the value, the more uneven the internal stress distribution of the steel cable, the greater the data fluctuation, the more obvious the difference in internal stress distribution caused by structural vibration, the more serious the impact of additional internal forces caused by vibration, and the lower the accuracy of the measurement data.

[0041] Step S30: Based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed cable, the degree of synergistic stress influence of the prestressed cable is calculated.

[0042] As an example, the previous steps analyzed the impact of different cable tension states on structural vibration from the perspective of individual cables. However, it is also necessary to analyze the coordinated stress of the cables as a whole. In a structure, cables do not exist in isolation; they form a mechanical whole through interconnected steel structures (such as bridge towers and main beams). Therefore, changes in the stress and vibration of one cable will inevitably affect the stress state of other cables through structural transmission. Similarly, the vibration degree of a single cable will also affect the surrounding cables. Thus, the overall vibration degree is affected by the coordinated changes of multiple cables. The higher the consistency of the changes, the more likely the structural vibration response is caused by external loads (such as vehicles or wind). Based on this, the degree of coordinated stress influence of prestressed cables is calculated. The degree of coordinated stress influence represents the extent to which prestressed cables are affected by the vibration of other cables. The greater the degree of coordinated stress influence, the more severely the measurement data corresponding to that cable is affected by the dynamic vibration of the structure, and the lower the accuracy of the measurement data.

[0043] Step S30 includes steps S31 to S34: Step S31: Based on the degree of stress non-uniformity and the stress measurement data at different measurement points, determine the instantaneous vibration sensitivity of the prestressed steel cable at each measurement moment.

[0044] As an example, the sensitivity of a single steel cable to vibration at a given moment is calculated. A higher sensitivity indicates a stronger response of the cable to external vibrations at that moment, and more severe dynamic interference to the measurement data. The steel cable in the first Taking this measurement as an example, instantaneous vibration sensitivity The calculation formula is as follows: In the formula, Indicates the first The degree of stress unevenness in the steel cable, Indicates the first Root steel cable The measurement point is the first The stress value measured is also known as the stress measurement data, where N represents the total number of measurement points.

[0045] Specifically, by combining the degree of uneven stress distribution within the steel cable with its instantaneous overall stress state, the sensitivity of the steel cable to vibration at the k-th data acquisition instant is quantified. The more uneven the stress and the higher the instantaneous stress of the steel cable, the more sensitive it is to external vibration at that moment. The larger.

[0046] Step S32: Based on the difference in instantaneous vibration sensitivity at different measurement times, the degree of cable fluctuation of each prestressed cable is calculated.

[0047] As an example, the degree of cable undulation is used to quantify the magnitude of change in the instantaneous vibration sensitivity of a cable over time, thereby reflecting the undulation characteristics of the cable under dynamic loads.

[0048] Step S32 includes: For any prestressed cable, calculate the third difference in the instantaneous vibration sensitivity between adjacent measurement times of the current prestressed cable.

[0049] The degree of cable fluctuation for each prestressed cable is calculated based on the sum of the third difference values ​​corresponding to each prestressed cable.

[0050] As an example, taking the a-th steel cable as an example, the degree of cable fluctuation... The calculation method can be: in, Indicates the first The steel cable in the first Instantaneous vibration sensitivity during the first measurement Indicates the first The steel cable in the first Instantaneous vibration sensitivity during the first measurement This represents the third difference.

[0051] Specifically, by summing the absolute values ​​of the instantaneous vibration sensitivity differences at consecutive measurement moments, the cumulative fluctuation degree of the steel cable during the entire measurement period is obtained, that is, the intensity of vibration fluctuation of a single steel cable throughout the entire data acquisition process. The larger the value, the more frequently and significantly the vibration sensitivity of the steel cable changes over time, indicating that it is more significantly affected by dynamic loads (such as wind and vehicles).

[0052] Step S33: Based on the difference between the degree of cable undulation and the average value of the degree of cable undulation, calculate the degree of consistency of stress change of each prestressed cable.

[0053] As an example, in a structure, because steel cables form a mechanical whole through interconnected steel structures (such as bridge towers and main beams), changes in the stress and vibration of one cable will inevitably affect the stress state of other cables through structural transmission. When the fluctuation of a certain cable is highly synchronized with the fluctuation of the overall cable structure, it indicates that the structural response is more likely caused by external loads (such as vehicles or wind). Taking the a-th cable as an example, the degree of consistency in stress change is denoted as... The calculation formula is as follows: in, Indicates the first The degree of cable undulation. Indicates all The average value of the fluctuation of the steel cable, where A represents the total number of steel cables.

[0054] Specifically, the absolute deviation between the degree of undulation of a single steel cable and the overall average degree of undulation is calculated. The smaller the value, the more synchronized the fluctuation of the cable is with the overall fluctuation of the cable, indicating a higher degree of consistency in stress changes. The larger the value, the more likely it is a structural vibration response caused by external loads (vehicle loads, wind loads); if A smaller value indicates abnormal fluctuations in the steel cable, which may be due to local damage or non-cooperative stress.

[0055] Step S34: Calculate the degree of influence of coordinated stress based on the product of stress non-uniformity and stress variation consistency.

[0056] As an example, a higher degree of consistency in stress variation indicates a more likely coordinated change across the entire cable. Fluctuations in this data are more likely the result of systemic vibration, making the measurements more susceptible to vibration and potentially leading to inaccuracies. The degree of coordinated force influence is denoted as... The calculation formula is as follows: In the formula, Indicates the first The degree of influence of the coordinated force on the steel cables Indicates the first The degree of consistency in stress variation of the steel cable. Indicates the first The degree of stress unevenness in the steel cable.

[0057] Specifically, the degree of influence of coordinated forces The larger the value, the more the fluctuation of the steel cable is driven by the overall structural vibration. The more severely the measurement data is affected by the dynamic vibration of the structure, the lower the accuracy of the measurement data. Therefore, it needs to be assigned a lower weight in the subsequent data correction to eliminate the error caused by vibration.

[0058] Step S40: Based on the degree of synergistic stress influence of different prestressed steel cables, determine the degree of overall structural vibration influence of each prestressed steel cable corresponding to the structure.

[0059] Step S40 includes: Based on the sum of the synergistic stress influence of different prestressed steel cables, the overall structural vibration influence of each prestressed steel cable is determined.

[0060] As an example, by superimposing the degree of influence of the coordinated stress on all steel cables, the dynamic environment (vehicle traffic, wind force) of the entire structure and its overall interference with the measurement are determined, that is, the degree of influence of the overall structural vibration.

[0061] Specifically, the calculation method for the overall structural vibration influence G can be as follows: in, This represents the degree of impact of vibration on the overall structure. Indicates the first The degree of influence of the coordinated force on the steel cables, where A represents the total number of steel cables.

[0062] in, The larger the value, the more significant the effect. The more severe the impact of dynamic vibration on the steel cable (e.g., uneven stress distribution and fluctuations synchronized with the overall structure), therefore... The larger the value, the more significant the impact of dynamic loads (such as wind loads and vehicle traffic) on the overall structure, the greater the overall fluctuation and error of the steel cable stress measurement data, and the lower the measurement accuracy.

[0063] Step S50: Based on the ratio between the degree of influence of coordinated stress and the degree of influence of overall structural vibration, the data acquisition accuracy of each prestressed steel cable is calculated.

[0064] As an example, vehicle traffic and wind can cause structural vibrations, putting the steel cables in a dynamic stress state, which can lead to insufficient accuracy in stress measurement. The aforementioned analysis has quantified the non-uniformity of individual steel cables and their synergistic impact on the overall structure. This step assesses the vibration disturbance level of the overall structure from a systemic perspective by comprehensively considering the synergistic stress effects of the steel cables, and finally calculates the data acquisition accuracy of the measured data for each steel cable, providing a basis for subsequent data adjustments.

[0065] Step S50 includes: Calculate the first ratio between the degree of influence of the coordinated force and the degree of influence of the overall structural vibration; The data acquisition accuracy of each prestressed steel cable is calculated based on the normalized value of the difference between the preset value and the first ratio.

[0066] As an example, the degree of synergistic effect of a single steel cable Overall impact The accuracy of data collection is calculated by the relative proportion of the data in the system. The higher the proportion, the more severely the data of the steel cable is affected by systematic vibration, and the lower its accuracy.

[0067] in, Indicates the first Accuracy of data collection for steel cables Indicates the first The degree of influence of the coordinated force on the steel cables This represents the degree of impact of vibration on the overall structure. Indicates the first The proportion of the influence of the coordinated force on the steel cable in the overall influence, also known as the first ratio, indicates that the steel cable is less affected by the overall vibration and the data acquisition accuracy is higher. norm() represents the normalization function.

[0068] Step S60: Based on the accuracy of data acquisition and the preset neural network model, the stress measurement data is corrected to eliminate errors in the stress measurement data.

[0069] As an example, the preset neural network model can be a recurrent neural network with an attention mechanism. The accuracy of data acquisition is used as the weight of the stress measurement data. The neural network is trained to correct the original stress measurement data, so as to eliminate the data measurement error caused by dynamic structural vibration, thereby obtaining more accurate internal stress data and eliminating the error of stress measurement data.

[0070] Step S60 includes: By fusing the accuracy of data acquisition with the stress measurement data, a multidimensional feature matrix is ​​constructed.

[0071] The pre-defined neural network model is iteratively trained using a multi-dimensional feature matrix to obtain the trained neural network model.

[0072] The trained neural network model is used to predict and process stress measurement data, and output corrected stress data to eliminate errors in the stress measurement data.

[0073] As an example, stress measurement data and data acquisition accuracy are fused to construct a multi-dimensional feature matrix. The multi-dimensional feature matrix is ​​then used to iteratively train a recurrent neural network (RNN) with an attention mechanism. The output layer is the corrected internal stress of the steel cable. After training, the original stress measurement data is input into the preset neural network model to obtain the corrected stress value of the steel cable and generate a stress distribution map of the steel cable.

[0074] As an example, the overall implementation flowchart of this application is as follows: Figure 2 As shown, by acquiring stress measurement data at different locations of the steel cable, the degree of stress non-uniformity, the degree of influence of synergistic force, and the degree of influence of structural vibration are calculated. Finally, the data acquisition accuracy is calculated, and the original stress measurement data is adjusted based on the data acquisition accuracy to eliminate the error in the stress measurement data.

[0075] This application provides a method for measuring the internal stress of prestressed steel cables. It acquires stress measurement data from different points on the prestressed steel cable, and then calculates the stress non-uniformity of the prestressed steel cable based on the stress measurement data and the degree of influence of external forces on each measurement point. Based on the stress non-uniformity and the consistency of stress changes in each prestressed steel cable, it calculates the degree of collaborative force influence of the prestressed steel cables. Furthermore, based on the degree of collaborative force influence of different prestressed steel cables, it calculates the degree of overall structural vibration influence of each prestressed steel cable. Then, based on the degree of collaborative force influence and the degree of overall structural vibration influence, it calculates the data acquisition accuracy of the prestressed steel cable. Finally, it corrects the stress measurement data using a preset neural network model and the data acquisition accuracy, outputting more accurate corrected stress measurement data, thereby eliminating errors in the stress measurement data and improving measurement accuracy. Finally, it adaptively adjusts the prestressed anchor cables based on the measurement data, improving the safety of the steel cable structure.

[0076] To achieve the above objectives, embodiments of this application also provide an internal stress measuring device for prestressed steel cables, comprising: The acquisition module is used to acquire stress measurement data at different measurement points on the prestressed steel cable; The first determining module is used to determine the degree of stress non-uniformity of the prestressed steel cable based on stress measurement data and the degree of influence of external forces on each measurement point; The first calculation module is used to calculate the degree of collaborative stress influence of the prestressed steel cables based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed steel cable. The second determining module is used to determine the degree of overall structural vibration impact of each prestressed steel cable based on the degree of collaborative stress influence of different prestressed steel cables. The second calculation module is used to calculate the data acquisition accuracy of each prestressed steel cable based on the ratio between the degree of influence of collaborative stress and the degree of influence of overall structural vibration. The calibration module is used to calibrate stress measurement data based on the accuracy of data acquisition and a preset neural network model, in order to eliminate errors in the stress measurement data.

[0077] Reference Figure 3 , Figure 3 This is a schematic diagram of the device structure of the hardware operating environment involved in the embodiments of this application.

[0078] like Figure 3 As shown, the internal stress measurement device applied to prestressed steel cables may include: a processor 1001, a memory 1003, and a communication bus 1002. The communication bus 1002 is used to realize the connection and communication between the processor 1001 and the memory 1003.

[0079] Optionally, the internal stress measurement device applied to prestressed steel cables may also include a user interface, a network interface, a camera, RF (Radio Frequency) circuitry, sensors, a WiFi module, etc. The user interface may include a display screen and an input submodule such as a keyboard; optional user interfaces may also include standard wired or wireless interfaces. The network interface may include standard wired or wireless interfaces (such as a Wi-Fi interface).

[0080] Those skilled in the art will understand that Figure 3 The internal stress measurement device structure shown in the figure for use with prestressed steel cables does not constitute a limitation on the internal stress measurement device for use with prestressed steel cables. It may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0081] like Figure 3 As shown, the memory 1003, serving as a storage medium, may include an operating system, a network communication module, and an internal stress measurement program for prestressed steel cables. The operating system is a program that manages and controls the hardware and software resources of the internal stress measurement equipment for prestressed steel cables, supporting the operation of the internal stress measurement program for prestressed steel cables and other software and / or programs. The network communication module is used to enable communication between the various components within the memory 1003, as well as communication with other hardware and software in the internal stress measurement system for prestressed steel cables.

[0082] exist Figure 3 In the internal stress measurement device for prestressed steel cables shown, the processor 1001 is used to execute the internal stress measurement program for prestressed steel cables stored in the memory 1003, and implement the steps of any of the above-mentioned internal stress measurement methods for prestressed steel cables.

[0083] The specific implementation of the internal stress measurement device for prestressed steel cables in this application is basically the same as the embodiments of the internal stress measurement method for prestressed steel cables described above, and will not be repeated here.

[0084] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0085] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0086] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0087] The above are merely preferred embodiments of this application and do not limit the scope of this application. Any equivalent structural or procedural transformations made based on the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the scope of protection of this application.

[0088] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0089] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

Claims

1. A method for measuring internal stress in prestressed steel cables, characterized in that, The method includes: Obtain stress measurement data at different measurement points on the prestressed steel cable; Based on the stress measurement data and the degree of influence of external forces on each measurement point, the degree of stress non-uniformity of the prestressed steel cable is determined. Based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed steel cable, the degree of synergistic stress influence of the prestressed steel cable is calculated. Based on the degree of synergistic stress influence of different prestressed steel cables, the degree of overall structural vibration influence of the corresponding structures of each prestressed steel cable is determined; Based on the ratio between the degree of influence of the coordinated stress and the degree of influence of the overall structural vibration, the data acquisition accuracy of each prestressed steel cable is calculated. Based on the accuracy of the data acquisition and the preset neural network model, the stress measurement data is corrected to eliminate errors in the stress measurement data.

2. The method for measuring internal stress in prestressed steel cables as described in claim 1, characterized in that, The determination of the stress non-uniformity of the prestressed steel cable based on the stress measurement data and the degree of influence of external forces at each measurement point includes: The preset stress value of the prestressed steel cable is determined, and the tension coefficient of the prestressed steel cable is calculated based on the difference between the average stress borne by the prestressed steel cable in the stress measurement data and the preset stress value. Based on the difference between the maximum value of the tension state coefficient and the tension state coefficient of each prestressed steel cable, the tension state influence coefficient of each prestressed steel cable is calculated. Based on the tension / slack state influence coefficient and the stress difference between the stress measurement data at different times, the vibration influence coefficient at different measurement points is calculated. Based on the fluctuation of the vibration influence coefficient at each measuring point on the prestressed steel cable, the degree of stress non-uniformity on each prestressed steel cable is calculated.

3. The method for measuring internal stress in prestressed steel cables as described in claim 2, characterized in that, The calculation of the tension state influence coefficient of each prestressed cable based on the difference between the maximum value of the tension state coefficient and the tension state coefficient of each prestressed cable includes: Determine the first difference between the maximum value of the tension state coefficient and the tension state coefficient of each of the prestressed steel cables; Based on the reciprocal of the first difference, the influence coefficient of the tension state of each prestressed steel cable is calculated.

4. The method for measuring internal stress in prestressed steel cables as described in claim 2, characterized in that, The vibration influence coefficient at different measurement points is calculated based on the tension / looseness influence coefficient and the stress difference between the stress measurement data at different times, including: Determine the second difference between the stress measurement data at different times and the minimum value of the stress measurement data; The vibration influence coefficient at different measurement points is calculated based on the product of the average value of each of the second differences and the influence coefficient of the tightness / slack state.

5. The method for measuring internal stress in prestressed steel cables as described in claim 1, characterized in that, The degree of cooperative stress influence of the prestressed cables is calculated based on the degree of stress non-uniformity and the consistency of stress changes in each prestressed cable, including: Based on the stress non-uniformity and stress measurement data at different measurement points, the instantaneous vibration sensitivity of the prestressed steel cable at each measurement moment is determined. Based on the difference in instantaneous vibration sensitivity at different measurement times, the degree of cable undulation of each prestressed cable is calculated. Based on the difference between the degree of cable undulation and the average value of the degree of cable undulation, the degree of consistency of stress change of each prestressed cable is calculated. The degree of influence of the coordinated stress is calculated based on the product of the stress non-uniformity and the degree of consistency of stress change.

6. The method for measuring internal stress in prestressed steel cables as described in claim 5, characterized in that, The degree of cable fluctuation of each prestressed cable is calculated based on the difference in instantaneous vibration sensitivity at different measurement times, including: For any prestressed cable, calculate the third difference in the instantaneous vibration sensitivity between adjacent measurement times of the current prestressed cable; The degree of cable fluctuation of each prestressed cable is calculated based on the sum of the third differences corresponding to each prestressed cable.

7. The method for measuring internal stress in prestressed steel cables as described in claim 1, characterized in that, The determination of the overall structural vibration impact degree of each prestressed cable's corresponding structure based on the degree of synergistic stress influence of different prestressed cables includes: Based on the sum of the synergistic stress influence of different prestressed steel cables, the overall structural vibration influence of the corresponding structure of each prestressed steel cable is determined.

8. The method for measuring internal stress in prestressed steel cables as described in claim 1, characterized in that, The accuracy of data acquisition for each prestressed steel cable is calculated based on the ratio between the degree of influence of the coordinated stress and the degree of influence of the overall structural vibration, including: Calculate a first ratio between the degree of influence of the coordinated force and the degree of influence of the overall structural vibration; The data acquisition accuracy of each prestressed steel cable is calculated based on the normalized value of the difference between the preset value and the first ratio.

9. The method for measuring internal stress in prestressed steel cables as described in claim 1, characterized in that, The step of correcting the stress measurement data based on the data acquisition accuracy and a preset neural network model to eliminate errors in the stress measurement data includes: The data acquisition accuracy is fused with the stress measurement data to construct a multi-dimensional feature matrix. The preset neural network model is iteratively trained using the multidimensional feature matrix to obtain the trained neural network model; The trained neural network model is used to predict and process the stress measurement data, and the corrected stress data is output to eliminate the error in the stress measurement data.

10. A device for measuring internal stress in prestressed steel cables, characterized in that, The device includes: The acquisition module is used to acquire stress measurement data at different measurement points on the prestressed steel cable; The first determining module is used to determine the degree of stress non-uniformity of the prestressed steel cable based on the stress measurement data and the degree of influence of the external force on each measurement point. The first calculation module is used to calculate the degree of collaborative stress influence of the prestressed steel cables based on the degree of stress non-uniformity and the consistency of stress change of each prestressed steel cable. The second determining module is used to determine the degree of overall structural vibration impact of each prestressed steel cable based on the degree of collaborative stress influence of different prestressed steel cables. The second calculation module is used to calculate the data acquisition accuracy of each of the prestressed steel cables based on the ratio between the degree of influence of the coordinated force and the degree of influence of the overall structural vibration. The calibration module is used to calibrate the stress measurement data based on the accuracy of the data acquisition and a preset neural network model, so as to eliminate the error in the stress measurement data.

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