A fatigue damage early warning method and device for a reinforced concrete structure, an electronic device, a storage medium and a program product

Abstract

This invention relates to the field of fatigue loss early warning technology for reinforced concrete structures, and discloses a fatigue damage early warning method, device, electronic equipment, storage medium, and program product for reinforced concrete structures. The invention acquires magnetic field data and calculates magnetic field changes and gradients by scanning sampling points of the component under test along a preset path. Combined with preset abrupt change conditions, it accurately locates dangerous areas, solving the problems of traditional methods in characterizing microscopic material damage and inability to target risks. Subsequently, it focuses on collecting magnetic field characteristic data in dangerous areas, judges structural fatigue damage based on its evolution law, and issues early warnings. This effectively avoids the shortcomings of traditional measurement methods, such as limited applicability, insufficient accuracy, and cumbersome operation, forming an efficient closed loop of location, monitoring, and early warning. It compensates for the shortcomings of existing technologies in efficiently and accurately completing assessment and early warning, significantly improving the timeliness and reliability of structural fatigue damage early warning.

Description

Technical Field

[0001] This invention relates to the field of fatigue loss early warning technology for reinforced concrete structures, specifically to a fatigue damage early warning method, device, electronic equipment, storage medium, and program product for reinforced concrete structures. Background Technology

[0002] Reinforced concrete structures are widely used in engineering fields such as bridges, industrial plants, high-rise buildings, and rail transit due to their high load-bearing capacity, excellent durability, and good economy. During their service life, they are often subjected to cyclic loads such as vehicle loads, mechanical vibrations, and wind loads. Fatigue damage accumulates gradually with each load cycle, leading to a decrease in structural stiffness and load-bearing capacity. In severe cases, this can cause sudden failure, resulting in significant economic losses and safety hazards. Therefore, accurate assessment and timely early warning of fatigue damage under cyclic loads are crucial for ensuring structural safety, extending service life, and developing scientific maintenance strategies, and have significant engineering implications.

[0003] Therefore, traditional measurement methods are typically used to measure fatigue loss in reinforced concrete structures. However, strain gauges require pre-embedding, making them unsuitable for existing structures and prone to debonding failure under cyclic loads. Dial gauges / force sensors can only reflect localized stress deformation, resulting in limited accuracy. Digital imaging technology (DIC) requires equipment setup and surface pretreatment, making it cumbersome and highly susceptible to environmental influences. These shortcomings prevent existing methods from efficiently and accurately completing assessments and early warnings, hindering the safe service life of structures. Summary of the Invention

[0004] This invention provides a fatigue damage early warning method, device, electronic equipment, storage medium, and program product for reinforced concrete structures, in order to solve the problem that existing methods cannot efficiently and accurately complete the assessment and early warning, making it difficult to ensure the safe service of the structure.

[0005] In a first aspect, the present invention provides a fatigue damage early warning method for reinforced concrete structures, the method comprising:

[0006] Multiple sampling points of the reinforced concrete component to be tested are scanned according to a preset magnetic field scanning path to obtain magnetic field data, and the magnetic field gradient is determined based on the magnetic field change in the magnetic field data. Determine whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets the preset abrupt change condition, and determine the danger zone based on the determination result; The dangerous area is monitored, and magnetic field characteristic data of the dangerous area are collected; Based on the evolution of the magnetic field characteristic data, the structural fatigue damage and damage area of ​​the reinforced concrete component under test are determined and a corresponding early warning signal is issued.

[0007] This invention acquires magnetic field data and calculates magnetic field changes and gradients by scanning sampling points of the component under test along a preset path. Combined with preset abrupt change conditions, it accurately locates dangerous areas, solving the problems of traditional methods in characterizing microscopic material damage and inability to target risks. Subsequently, it focuses on collecting magnetic field characteristic data in dangerous areas, judges structural fatigue damage based on its evolution law, and issues early warnings. This effectively avoids the shortcomings of traditional measurement methods, such as limited applicability, insufficient accuracy, and cumbersome operation, forming an efficient closed loop of positioning, monitoring, and early warning. It makes up for the shortcomings of existing technologies in efficiently and accurately completing assessment and early warning, and significantly improves the timeliness and reliability of structural fatigue damage early warning.

[0008] In one optional implementation, the step of scanning multiple sampling points of the reinforced concrete member to be tested according to a preset magnetic field scanning path to obtain magnetic field data, and determining the magnetic field gradient based on the magnetic field change in the magnetic field data, includes: The sampling points on the surface of the reinforced concrete member to be viewed are scanned according to the preset magnetic field scanning path to obtain the normal magnetic field component, tangential magnetic field component and corresponding position information of each sampling point. The normal magnetic field component and the tangential magnetic field component are subjected to noise reduction filtering preprocessing to obtain magnetic field data; The change in normal magnetic field is calculated using the normal magnetic field component of the magnetic field data and the normal magnetic field of the initial healthy state. The change in tangential magnetic field is calculated using the tangential magnetic field component of the magnetic field data and the initial healthy state tangential magnetic field. A two-dimensional magnetic field distribution map is constructed by interpolating the normal magnetic field change, tangential magnetic field change, and corresponding location information of the sampling points. Based on the two-dimensional magnetic field distribution map, the magnetic field gradient magnitudes corresponding to the normal magnetic field and tangential magnetic field at each sampling point are calculated.

[0009] This invention scans sampling points on the surface of a component along a preset path to simultaneously acquire the normal and tangential magnetic field components and their location information. After noise reduction and filtering preprocessing to optimize data quality, the change in magnetic field is accurately calculated by combining the initial healthy state magnetic field data. Then, a continuous two-dimensional magnetic field distribution map is constructed using interpolation. Finally, the magnetic field gradient magnitude of each sampling point is solved. This effectively solves the problems of traditional methods being unable to characterize microscopic damage in materials and having insufficient positioning accuracy, and significantly improves the reliability and completeness of magnetic field data. It can clearly capture magnetic field anomalies caused by stress concentration inside the structure.

[0010] In one optional implementation, determining whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets a preset abrupt change condition, and determining the danger zone based on the determination result, includes: Determine whether the magnitude of the magnetic field gradient corresponding to the normal magnetic field or tangential magnetic field at the sampling point is greater than a preset abrupt change threshold; If so, the sampling point is determined as a mutation point; If not, then determine whether the curves corresponding to the normal magnetic field change or tangential magnetic field change of the sampling points in the two-dimensional magnetic field distribution map have peaks or zero points. If so, the sampling point is determined as a mutation point; By combining the aforementioned mutation points, the banded regions are obtained; Calculate the severity index of each strip region, and determine the preset number of strip regions corresponding to the maximum severity index as danger zones.

[0011] This invention selects the magnetic field gradient magnitude corresponding to the normal and tangential magnetic fields, and combines the gradient magnitude exceeding a preset threshold and the peak or zero crossing of the magnetic field change curve as dual criteria to accurately identify abrupt change points. Then, through strip region integration and severity index quantification screening, it efficiently locks the core dangerous area, solving the problems of traditional methods that are difficult to accurately capture abnormal signals caused by micro-damage and the ambiguity of dangerous area positioning. It greatly improves the pertinence and reliability of dangerous area judgment and effectively avoids the risk of missed judgment and misjudgment.

[0012] In one optional implementation, monitoring the hazardous area and collecting magnetic field characteristic data of the hazardous area includes: Multiple magnetic probes are installed in the hazardous area according to preset locations; The magnetic field characteristic data of the dangerous area are obtained by collecting the normal magnetic field strength, tangential magnetic field strength, and residual magnetic induction intensity after unloading for a single cycle at each preset point using the magnetic probes.

[0013] This invention deploys multiple magnetic probes at preset locations within the identified hazardous area to specifically collect the normal and tangential magnetic field strengths, as well as the residual magnetic induction intensity after a single cycle of unloading. This accurately obtains core magnetic field characteristic data of the hazardous area, effectively avoiding the shortcomings of traditional measurement methods, such as the need to pre-bury measurement points, the ability to reflect only local information, or cumbersome operations. It achieves targeted and focused monitoring of high-risk areas.

[0014] In one optional implementation, determining the structural fatigue damage and damage area of ​​the reinforced concrete component under test based on the evolution law of the magnetic field characteristic data and issuing a corresponding early warning signal includes: The magnetic probe's acquisition time of the magnetic field characteristic data is divided into multiple time windows according to a preset time interval; Extract the minimum residual magnetic flux density after unloading for all single cycles within the time window to obtain the magnetic flux density characteristic value of the time window; By iterating through all the time windows of the acquisition time and collecting the characteristic values ​​of the magnetic field induction intensity and the corresponding timestamps, a scatter sequence of the magnetic probe is obtained. The slope of each magnetic probe is obtained by performing least squares linear fitting on multiple consecutive scattered points of the scattered point sequence of each magnetic probe. The relative growth rate of the slope is determined based on the slopes of any two adjacent magnetic probes. Determine whether the relative growth rate of the slope corresponding to multiple consecutive time windows of the magnetic probe is greater than a preset warning threshold; If so, it is determined that the reinforced concrete component under test has structural fatigue damage, and a corresponding warning message is issued; If not, then determine whether there is a preset number of magnetic probes whose relative growth rate of slope corresponding to the time window of the magnetic probe is greater than a preset warning threshold. If so, the test reinforced concrete component is determined to have structural fatigue damage and the damaged area of ​​the structural fatigue damage, and a corresponding warning message is issued.

[0015] This invention divides time windows by preset time intervals, extracts the minimum residual magnetic induction intensity within the window as a feature value, constructs a scatter sequence by combining timestamps, and obtains the slope by linear fitting using the least squares method. By calculating the relative growth rate of adjacent slopes, and then using the dual criteria of multiple consecutive window growth rates exceeding a threshold and a preset number of probes meeting the standard, the damage area of ​​fatigue damage and structural fatigue damage is determined and an early warning is issued. This effectively solves the problems of traditional methods being unable to capture the evolution law of fatigue damage and insufficient timeliness and accuracy of early warning.

[0016] In an optional implementation, the method further includes: The preset points in the danger zone are repeatedly scanned according to the preset scanning step size to obtain the initial scan data and the current rescan data. Calculate the normal magnetic field second difference field and the tangential magnetic field second difference field between the initial scan data and the current rescan data of the preset points in the dangerous area; The latest magnetic field gradient magnitude of the normal magnetic field at the preset point is calculated using the second difference field of the normal magnetic field. The latest magnetic field gradient magnitude of the tangential magnetic field at the preset point is calculated using the second difference field of the tangential magnetic field. Determine whether the latest magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field at each preset point is greater than the preset mutation threshold, and determine the damage location information based on the latest determination result; The dangerous area was reinforced and repaired according to the damage location information.

[0017] This invention repeatedly scans the dangerous area by setting a preset scanning step size, calculates the normal and tangential magnetic field second difference fields by combining the initial scan data and the current rescan data, and then solves the latest magnetic field gradient magnitude. Based on the comparison between the maximum latest gradient magnitude and the preset mutation threshold, the damage location information is accurately determined, and finally reinforcement and repair are carried out according to the information. This effectively solves the problems of vague damage location and difficulty in accurately locating the disease in traditional methods.

[0018] Secondly, the present invention provides a fatigue damage early warning device for reinforced concrete structures, the device comprising: The scanning module is used to scan the surface of the reinforced concrete component to be tested according to a preset magnetic field scanning path, obtain magnetic field data, and determine the magnetic field gradient based on the magnetic field change in the magnetic field data. The judgment module is used to determine whether the gradient magnitude value corresponding to the magnetic field gradient is greater than a preset abrupt change threshold, and to determine the dangerous area of ​​the reinforced concrete component to be tested based on the judgment result. The monitoring module is used to monitor the dangerous area and collect magnetic field characteristic data of the dangerous area; The early warning module is used to determine the structural fatigue damage and damage area of ​​the reinforced concrete component under test based on the evolution law of the magnetic field characteristic data and to issue a corresponding early warning signal.

[0019] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the fatigue damage early warning method for reinforced concrete structures described in the first aspect or any corresponding embodiment.

[0020] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the fatigue damage early warning method for reinforced concrete structures described in the first aspect or any corresponding embodiment thereof.

[0021] Fifthly, the present invention provides a computer program product, including computer instructions, which are used to cause a computer to execute the fatigue damage early warning method for reinforced concrete structures described in the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic flowchart of a first method for early warning of fatigue damage in reinforced concrete structures according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the second process of the fatigue damage early warning method for reinforced concrete structures according to an embodiment of the present invention. Figure 3 This is a scanning schematic diagram of a magnetic probe according to an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the application of magnetic field characteristic data for early warning according to an embodiment of the present invention; Figure 5 This is a schematic diagram of repeated scanning of dangerous areas according to an embodiment of the present invention; Figure 6 This is a structural block diagram of a fatigue damage early warning device for reinforced concrete structures according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0026] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] This invention provides a fatigue damage early warning method for reinforced concrete structures. By scanning sampling points of the component under test along a preset path, magnetic field data is obtained and the magnetic field change and gradient are calculated. Combined with preset abrupt change conditions, the dangerous area is accurately located, solving the problems of traditional methods in being unable to characterize microscopic material damage and target risk location. Subsequently, magnetic field characteristic data is collected focusing on the dangerous area, and the fatigue damage of the structure is judged and an early warning is issued based on its evolution law. This effectively avoids the defects of traditional measurement methods, such as limited applicability, insufficient accuracy, and cumbersome operation, forming an efficient closed loop of location, monitoring, and early warning. It makes up for the shortcomings of existing technologies in efficiently and accurately completing assessment and early warning, thereby improving the timeliness and reliability of structural fatigue damage early warning.

[0028] According to an embodiment of the present invention, a fatigue damage early warning method for reinforced concrete structures is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0029] This embodiment provides a method for early warning of fatigue damage in reinforced concrete structures. Figure 1 This is a flowchart of a fatigue damage early warning method for reinforced concrete structures according to an embodiment of the present invention, such as... Figure 1 As shown, the process includes the following steps: Step S101: Scan multiple sampling points of the reinforced concrete component to be tested according to the preset magnetic field scanning path to obtain magnetic field data, and determine the magnetic field gradient based on the magnetic field change in the magnetic field data.

[0030] It should be noted that the preset magnetic field scanning path refers to the path pre-planned to achieve a comprehensive scan of the component, usually based on the component's axial direction. x Axis and transverse are y axis.

[0031] The reinforced concrete component to be tested refers to a reinforced concrete structural component (the steel is a ferromagnetic material) that requires fatigue damage detection and evaluation.

[0032] Sampling points refer to discrete points selected uniformly along the scanning path for collecting magnetic field data.

[0033] Magnetic field data refers to the data collected during the scanning process that reflects the magnetic field characteristics of the component surface.

[0034] The change in magnetic field refers to the difference between the measured magnetic field data and the initial healthy state magnetic field data, including the change in normal magnetic field and the change in tangential magnetic field.

[0035] Magnetic field gradient refers to a physical quantity that characterizes the rate of change of a magnetic field.

[0036] In this embodiment of the invention, the reinforced concrete member to be tested is preset to be axially... x Axis and transverse are y The magnetic field scanning path of the shaft is set with a fixed step size and lift-off height. Multiple sampling points on the surface of the component are scanned one by one along the path. The normal magnetic field component, tangential magnetic field component and corresponding position information of each sampling point are collected simultaneously to form initial magnetic field data. Then, the initial magnetic field data is preprocessed by noise reduction filtering. Combined with the normal reference magnetic field and tangential reference magnetic field recorded in the initial healthy state of the component without external load, the change in normal magnetic field and tangential magnetic field of each sampling point are calculated respectively. Then, based on the change in normal magnetic field and tangential magnetic field, the magnetic field gradient corresponding to each sampling point is obtained by the difference operation of the magnetic field change of adjacent sampling points.

[0037] Step S102: Determine whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets the preset abrupt change conditions, and determine the danger zone based on the determination result.

[0038] It should be noted that the gradient magnitude refers to the scalar value after vector synthesis of the magnetic field gradient.

[0039] Preset mutation conditions refer to pre-defined criteria used to determine whether there are abnormal mutations in the magnetic field at the sampling point.

[0040] The danger zone refers to a pre-defined number of areas selected from the strip regions that have the best severity index.

[0041] In this embodiment of the invention, the gradient magnitude corresponding to the magnetic field gradient is compared with a preset mutation threshold. At the same time, the curve characteristics corresponding to the change in magnetic field are combined for comprehensive judgment. If the gradient magnitude is greater than the preset mutation threshold, or the curve of the change in magnetic field shows peak or zero-crossing characteristics, the corresponding sampling point is determined to be a mutation point. Then, adjacent and connected mutation points are integrated to form strip regions. The severity index (such as the maximum gradient magnitude) of each strip region is calculated. The preset number of strip regions with the best severity index is selected and finally determined as the dangerous areas that need to be monitored.

[0042] Step S103: Monitor the dangerous area and collect magnetic field characteristic data of the dangerous area.

[0043] It should be noted that magnetic field characteristic data refers to the core magnetic field data that characterizes the stress state and damage evolution of steel bars in the dangerous area, including the normal magnetic field strength, the tangential magnetic field strength, and the residual magnetic induction intensity after a single cycle of unloading.

[0044] In this embodiment of the invention, multiple magnetic probes are arranged at preset points such as the center and both ends of the main reinforcement in the dangerous area, and the coordinates of each preset point are recorded. The magnetic field signals in the dangerous area are continuously monitored through these magnetic probes, and the normal magnetic field strength, tangential magnetic field strength, and residual magnetic induction intensity of each preset point are collected simultaneously. These magnetic field-related data that can reflect the stress and damage state of the steel reinforcement are integrated to form the magnetic field characteristic data of the dangerous area.

[0045] Step S104: Based on the evolution law of magnetic field characteristic data, determine the structural fatigue damage and damage area of ​​the reinforced concrete component to be tested and issue a corresponding early warning signal.

[0046] It should be noted that the evolution law of magnetic field characteristic data refers to the trend of change of magnetic field characteristic data with monitoring time or number of load cycles.

[0047] Structural fatigue damage refers to the slow accumulation of damage to components under cyclic loading due to stress concentration in steel reinforcement, degradation of material properties, and other factors.

[0048] Damage area refers to the location information of structural fatigue damage in the reinforced concrete component under test.

[0049] A warning signal is a signal issued when structural fatigue damage is determined to have reached a preset risk level, indicating that further measures need to be taken.

[0050] In this embodiment of the invention, the collection time of magnetic field characteristic data of the dangerous area is divided into time windows according to a preset time interval or cyclic interval. The characteristic value of the residual magnetic induction intensity after a single cycle of unloading in each window is extracted and combined with the corresponding timestamp to form a scatter sequence. The slope of each window is obtained by sliding linear fitting, and the relative growth rate of adjacent slopes is calculated. If the relative growth rate of the slope of multiple consecutive windows exceeds a preset warning threshold, or if a preset number of magnetic probes simultaneously meet the condition, it is determined that the evolution law of the magnetic field characteristic data reflects that the fatigue damage of the component structure has reached the warning level. Based on the damage state and damage area of ​​the component structure fatigue damage, a corresponding warning signal is issued.

[0051] This embodiment provides a method for early warning of fatigue damage in reinforced concrete structures. Figure 2 This is a flowchart of a fatigue damage early warning method for reinforced concrete structures according to an embodiment of the present invention, such as... Figure 2 As shown, the process includes the following steps: Step S201: Scan multiple sampling points of the reinforced concrete component to be tested according to the preset magnetic field scanning path to obtain magnetic field data, and determine the magnetic field gradient based on the magnetic field change in the magnetic field data.

[0052] Specifically, step S201 includes: Step S2011: Scan each sampling point on the surface of the reinforced concrete member to be viewed according to the preset magnetic field scanning path to obtain the normal magnetic field component, tangential magnetic field component and corresponding position information of each sampling point.

[0053] It should be noted that the normal magnetic field component refers to the magnetic field strength component perpendicular to the surface of the reinforced concrete member being measured.

[0054] The tangential magnetic field component refers to the magnetic field strength component parallel to the surface of the reinforced concrete member being measured.

[0055] Location information refers to the location of each sampling point within a preset range. xy The specific coordinates in the coordinate system.

[0056] In embodiments of the present invention, such as Figure 3 As shown, a wheel-type magnetic probe is used to scan along a set path (along the axial direction of the reinforced concrete member to be scanned). x , horizontal y ; with step size Lifting height value The sampling points on the surface of the reinforced concrete member to be tested are scanned, and a wheel-type magnetic probe (such as TSC-8M) records the normal magnetic field component at each sampling point. With tangential magnetic field component (or corresponding) H (Components), and simultaneously record location information.

[0057] Step S2012: Perform noise reduction filtering preprocessing on the normal magnetic field component and the tangential magnetic field component to obtain magnetic field data.

[0058] It should be noted that noise reduction filtering preprocessing refers to the preliminary data processing operations performed to improve the reliability of magnetic field data.

[0059] In this embodiment of the invention, the normal magnetic field component and the tangential magnetic field component of each sampling point of each scanning path are subjected to noise reduction filtering preprocessing, specifically as follows: Noise reduction filtering: Moving average, median filtering, and low-pass filtering methods can be used to obtain magnetic field data. , .

[0060] Step S2013: Using the normal magnetic field component of the magnetic field data and the normal magnetic field of the initial healthy state, calculate the change in the normal magnetic field.

[0061] It should be noted that the initial healthy state normal magnetic field refers to the reference value of the normal magnetic field at each sampling point of the component under test in a good state without fatigue damage and without being subjected to external loads.

[0062] The change in normal magnetic field refers to the difference between the measured normal magnetic field component at the same sampling point and the normal magnetic field in the initial healthy state.

[0063] In this embodiment of the invention, the initial magnetic field calibration is as follows: before the external load is applied, the normal magnetic field used to construct the initial health scan is used as the reference normal magnetic field, which is the initial health state normal magnetic field. The change in the normal magnetic field is:

[0064] In the formula, Indicates the normal magnetic field component; This represents the normal magnetic field in the initial healthy state.

[0065] Step S2014: Using the tangential magnetic field component of the magnetic field data and the tangential magnetic field of the initial healthy state, calculate the change in the tangential magnetic field.

[0066] It should be noted that the initial healthy state tangential magnetic field refers to the reference value of the tangential magnetic field at each sampling point of the component under test in a good state without fatigue damage and without being subjected to external loads.

[0067] The change in normal magnetic field refers to the difference between the measured tangential magnetic field component at the same sampling point and the tangential magnetic field in the initial healthy state.

[0068] In this embodiment of the invention, the initial magnetic field calibration is as follows: before the external load is applied, the tangential magnetic field used to construct the initial health scan is used as the reference tangential magnetic field, which is the initial health state tangential magnetic field. The change in the tangential magnetic field is:

[0069] In the formula, Indicates the normal magnetic field component; This represents the normal magnetic field in the initial healthy state.

[0070] The changes in the normal magnetic field and the changes in the tangential magnetic field are used to offset the deviations caused by the ambient magnetic field.

[0071] Step S2015: Construct a two-dimensional magnetic field distribution map by interpolating the changes in the normal magnetic field, the changes in the tangential magnetic field, and the corresponding location information of the sampling points.

[0072] It should be noted that interpolation is a mathematical method used to supplement discrete data points into continuous data.

[0073] A two-dimensional magnetic field distribution map refers to an image of magnetic field variation distribution presented in a two-dimensional plane, constructed using interpolation methods.

[0074] In this embodiment of the invention, the sampling points , Interpolation methods such as bilinear interpolation or spline interpolation are used to process the discrete magnetic field data of the sampling points into a continuous form. The magnetic field changes (normal magnetic field changes and tangential magnetic field changes) are integrated with the location information one by one, and finally a two-dimensional magnetic field distribution map that can intuitively present the magnetic field changes on the surface of the component is constructed.

[0075] Step S2016: Based on the two-dimensional magnetic field distribution map, solve for the magnetic field gradient magnitudes corresponding to the normal magnetic field and tangential magnetic field at each sampling point.

[0076] It should be noted that the magnitude of the magnetic field gradient refers to the magnitude of the magnetic field gradient. x axis, y The scalar value of the gradient in the axial direction after vector synthesis.

[0077] In this embodiment of the invention, the collected sampling points / discrete points , The calculation method defines abrupt changes in the gradient characteristics of the data. The calculation method is to construct the magnetic field magnitude of the magnetic field gradient along the detection line using the difference between adjacent points. G : ; ; ; ; ; ; In the formula, , They represent the first i indivual, j The coordinates of each sampling position in the two-dimensional scanning plane, among which i Indicates along x Discrete index of direction (component axis / scan line direction), j Indicates along y Discrete index of direction (horizontal / adjacent scan line direction); 、 Representing the coordinates The normal / tangential magnetic field difference at the location, where The component of the magnetic induction intensity of the normal magnetic field; , These represent the two-dimensional scan grid in... x / y Sampling interval (step size) in the direction; , They represent exist along x / y Discrete approximation of the gradient in the direction (using central difference); , They represent exist along x / y Discrete approximation of the gradient in the direction (central difference); This represents the maximum gradient magnitude within the scanned region, used to quantitatively describe the degree of abrupt changes in the magnetic field. The maximum value is selected. Describe the degree of mutation.

[0078] Step S202: Determine whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets the preset abrupt change conditions, and determine the danger zone based on the determination result.

[0079] In some optional implementations, step S202 above includes: Step S2021: Determine whether the magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field of the sampling point is greater than the preset abrupt change threshold.

[0080] It should be noted that the preset mutation threshold refers to the critical value set based on engineering experience and experimental data, which includes but is not limited to the mean ± 5 times the standard deviation.

[0081] In this embodiment of the invention, the magnetic field gradient magnitudes corresponding to the normal magnetic field and tangential magnetic field of each sampling point are compared with preset mutation thresholds for judgment.

[0082] Step S2022: If yes, then the sampling point is determined as a mutation point.

[0083] It should be noted that the mutation point refers to the sampling point that meets the preset mutation condition (the magnitude of the magnetic field gradient exceeds the preset threshold).

[0084] In an embodiment of the present invention, if or If a point is identified as a mutation point, then connecting adjacent mutation points forms a candidate danger zone.

[0085] Step S2023: If not, determine whether the curves corresponding to the normal magnetic field change or tangential magnetic field change of the sampling points in the two-dimensional magnetic field distribution map have peaks or zero points.

[0086] It should be noted that the peak value refers to the local maximum value point in the fitted curve of the magnetic field change.

[0087] The zero-crossing point of the curve refers to the critical point at which the change in magnetic field changes from a positive value to a negative value or from a negative value to a positive value.

[0088] In an embodiment of the present invention, if or Then determine the normal magnetic field change or tangential magnetic field change corresponding to the sampling point in the two-dimensional magnetic field distribution map. , Whether the curve exhibits peak values ​​or zero-crossing characteristics.

[0089] Step S2024: If yes, then the sampling point is determined as a mutation point.

[0090] In this embodiment of the invention, if the sampling point corresponds to the change in normal magnetic field or the change in tangential magnetic field in the two-dimensional magnetic field distribution map... , The sampling point is identified as a point of sudden change when the curve shows a peak or crosses zero.

[0091] Step S2025: Combine the mutation points to obtain the band region.

[0092] It should be noted that a strip region refers to a continuous strip-shaped region formed by the convergence of adjacent and connected abrupt change points.

[0093] In this embodiment of the invention, the set of mutation points that meet the criteria is used to obtain several abnormal patches or band regions. .

[0094] Step S2026: Calculate the severity index of each strip region, and determine the preset number of strip regions corresponding to the maximum severity index as danger zones.

[0095] It should be noted that the severity index refers to a parameter used to quantify the degree of magnetic field anomaly in the strip region and the corresponding risk of damage.

[0096] The preset quantity refers to the number of strip areas to be screened in advance based on the actual needs of the project and the requirements for detection accuracy.

[0097] In this embodiment of the invention, the severity index of each strip region is calculated ( , Select the largest single region as the danger zone and define its coordinate bounding box. .

[0098] Step S203: Monitor the hazardous area and collect magnetic field characteristic data of the hazardous area.

[0099] Specifically, step S203 includes: Step S2031: Install multiple magnetic probes in the hazardous area according to the preset locations.

[0100] It should be noted that the preset points refer to the pre-planned installation locations of magnetic probes based on the scope of the hazardous area, the distribution of the main reinforcement bars of the components, and the monitoring requirements.

[0101] In this embodiment of the invention, in the hazardous area Inside, arranged along the direction of the main reinforcement bars. n One magnetic probe, model MODEL-191, can be selected. Preset points can be: the center of the area + both ends. Record the coordinates of each preset point. .

[0102] Step S2032: Collect the normal magnetic field strength, tangential magnetic field strength, and residual magnetic induction intensity after unloading for a single cycle at each preset point using each magnetic probe to obtain the magnetic field characteristic data of the dangerous area.

[0103] It should be noted that the normal magnetic field strength refers to the magnetic field strength in the direction perpendicular to the surface of the reinforced concrete component being tested.

[0104] Tangential magnetic field strength refers to the magnetic field strength parallel to the axial direction of the surface of the reinforced concrete member being tested.

[0105] The residual magnetic flux density after a single unloading cycle refers to the magnetic field strength remaining in the hazardous area after a component has undergone a complete load-unloading cycle.

[0106] In this embodiment of the invention, the normal and tangential magnetic field magnetic induction components at the measurement point location (i.e., the preset point) are continuously recorded, as well as the tail of the hysteresis curve of a single cycle (the residual magnetic field magnetic induction intensity after unloading to the minimum load in a single cycle), and recorded in Table 1 below: Table 1. Magnetic field characteristics data of the hazardous area

[0107] Step S204: Based on the evolution law of magnetic field characteristic data, determine the structural fatigue damage and damage area of ​​the reinforced concrete component to be tested and issue a corresponding early warning signal.

[0108] In some optional implementations, step S204 above includes: Step S2041: Divide the acquisition time of magnetic field characteristic data by the magnetic probe into multiple time windows according to a preset time interval.

[0109] It should be noted that the preset time interval refers to a fixed time length pre-set based on monitoring accuracy, damage evolution rate, and engineering requirements.

[0110] Acquisition time refers to the total time from when the magnetic probe starts acquiring magnetic field characteristic data to the current moment.

[0111] A time window refers to a single time segment after a preset time interval has been divided. Each window corresponds to magnetic field characteristic data within a continuous duration.

[0112] In this embodiment of the invention, the entire duration of the magnetic probe continuously collecting magnetic field feature data is divided into multiple continuous and non-overlapping time windows according to a pre-set fixed time interval, and each time window corresponds to magnetic field feature data within a certain duration.

[0113] Step S2042: Extract the minimum residual magnetic induction intensity after unloading for all single cycles within the time window to obtain the characteristic value of magnetic field induction intensity of the time window.

[0114] It should be noted that the minimum value refers to the smallest value selected from multiple residual magnetic induction intensity data within a single time window.

[0115] The characteristic value of magnetic field induction intensity refers to a quantitative index determined by the minimum value of residual magnetic induction intensity within a single time window.

[0116] In this embodiment of the invention, a time window is used. (or recirculating window) (in units of) in the first i Take a number of loop iterations within a time window. ,exist Internally, extract the residual magnetic induction intensity after each unloading. The minimum value is used as the criterion. Among them, the first... i The residual magnetic flux density after each unloading within a time window / cycle window The minimum value is:

[0117] In the formula, Indicates the first k The magnetic probe collected the first... i The residual magnetic flux density after each unloading within a time window / cycle window.

[0118] Step S2043: Traverse the magnetic field induction intensity characteristic values ​​and corresponding timestamps of all time windows of the acquisition time to obtain the scatter sequence of the magnetic probe.

[0119] It should be noted that a timestamp refers to a time marker that records the moment when magnetic field data is collected for each time window.

[0120] A scatter sequence refers to a discrete data set composed of the characteristic values ​​of magnetic field induction intensity for each time window and their corresponding timestamps.

[0121] In this embodiment of the invention, the magnetic field induction intensity characteristic value of each time window is synchronously retrieved from the timestamp corresponding to each time window (i.e., the corresponding time of data acquisition for each window). All time windows within the entire acquisition time are traversed, and the magnetic field induction intensity characteristic value of each time window is associated with its corresponding timestamp one-to-one, ultimately forming the magnetic probe's... PM Scatter series .

[0122] Step S2044: Perform least squares linear fitting on multiple consecutive scattered points of the scattered point sequence of each magnetic probe to obtain the slope of each magnetic probe.

[0123] It should be noted that continuous scatter points refer to adjacent data points arranged in chronological order of timestamps in a scatter point sequence.

[0124] Least squares is a mathematical fitting method that finds the optimal function match for data by minimizing the sum of squared errors.

[0125] Linear fitting refers to constructing a linear functional relationship between scattered data and timestamps based on the least squares method.

[0126] The slope refers to the slope value of the linear equation obtained by linear fitting.

[0127] In this embodiment of the invention, for each probe k The PM scatter sequence was obtained. Take continuous n A least-squares linear fit is performed on the scattered points, and the slope can be expressed by the following formula:

[0128] In the formula, Indicates the first k The probe is at the first i Magnetic feature values ​​extracted within a time window; Indicates the first i The time corresponding to each scatter point; Indicates the first k The probe is at the first i The fitting slope obtained within each fitting window (characterized by...) PM (rate of change over time) c Represents the intercept term of the linear fit; n This represents the number of continuous scatter points used for least-squares linear fitting; k Indicates the magnetic probe number. ,in m This represents the total number of magnetic probes deployed.

[0129] Its slope can be calculated using an explicit formula:

[0130] In the formula, Indicates the first i Within a sliding window n One point.

[0131] Step S2045: Determine the relative growth rate of the slope based on the slopes of each pair of adjacent magnetic probes.

[0132] It should be noted that the relative growth rate of the slope refers to a parameter calculated by the ratio of the difference between adjacent slopes to the previous slope.

[0133] In this embodiment of the invention, the difference between two adjacent slopes is selected to calculate the relative growth rate of the slope. The specific calculation formula is as follows:

[0134] In the formula, Indicates the first k The probe is at the first i The relative growth rate of the slope corresponding to each fitting window is used to characterize the degree of sudden increase in slope. , They represent the first k The probe is currently the [number]th [number]. i Each fitting window, and the previous adjacent window The obtained fitting slope.

[0135] Step S2046: Determine whether the relative growth rate of the slope corresponding to multiple consecutive time windows of the magnetic probe is greater than the preset warning threshold.

[0136] It should be noted that the preset warning threshold ( (50%) refers to the critical value set based on engineering experience, experimental data, and structural safety requirements, which includes but is not limited to 50%.

[0137] In this embodiment of the invention, the relative growth rate of the slope corresponding to multiple consecutive time windows of the magnetic probe is judged one by one to be greater than a preset warning threshold.

[0138] Step S2047: If yes, then determine that the reinforced concrete member under test has structural fatigue damage and the damaged area of ​​structural fatigue damage, and issue the corresponding warning information.

[0139] It should be noted that the warning information refers to the alert signal generated based on the damage risk level.

[0140] In this embodiment of the invention, when the slope is relative to the growth rate At that time, it is considered that an alarm has been triggered within a single measurement window. Furthermore, the criteria for determining alarms from a single magnetic probe and alarms within a hazardous area are as follows: (1) For a single magnetic probe, the following conditions must be met within 10 consecutive windows: Only then was the alarm triggered; (2) m An alarm will only be triggered if at least half of the probes are activated simultaneously.

[0141] At the same time, corresponding warning information is sent.

[0142] Step S2048: If not, determine whether there is a preset number of magnetic probes whose relative growth rate of slope corresponding to the time window is greater than the preset warning threshold.

[0143] It should be noted that the preset number refers to 1 / 2 probe.

[0144] In this embodiment of the invention, if for a single magnetic probe, the following condition is not met within 10 consecutive windows: , then judge m Are there at least 1 / 2 of the probes whose relative slope growth rate corresponds to a time window greater than a preset warning threshold?

[0145] Step S2049: If yes, then determine that the reinforced concrete component under test has structural fatigue damage and issue a corresponding warning message.

[0146] In an embodiment of the present invention, if m An alarm will only be triggered if the relative growth rate of the slope corresponding to the time window of at least 1 / 2 of the probes exceeds the preset warning threshold, and a corresponding warning message will be sent at the same time.

[0147] It is worth mentioning that, such as Figures 3 to 5 The curve graph in the image can be selected to be at certain time intervals. The minimum magnetic field value within the area was determined, and the evolution curve of the magnetic characteristic index over recording time was plotted (magnetic index-time evolution curve). Based on the scatter plot of the recorded magnetic characteristic index... ,by n Slope fitting was performed on the scattered points, and the results were recorded as follows: When two adjacent When the relative growth rate exceeds a certain threshold (which can be taken as 50%), fatigue failure is considered to be imminent.

[0148] Step S205: Repeatedly scan each preset point in the danger zone according to the preset scanning step length to obtain the initial scan data and the current rescan data.

[0149] It should be noted that the preset scanning step length refers to the distance the detection equipment moves between points, which is preset based on the monitoring accuracy and efficiency.

[0150] Initial scan data refers to the magnetic field-related data collected during the first scan of preset points in the hazardous area.

[0151] The current rescan data refers to the magnetic field data of the preset points in the danger zone collected during this repeated scan.

[0152] In this embodiment of the invention, after the warning is triggered, only the dangerous area is affected. Perform a higher resolution rescan to obtain the initial scan data and the current rescan data, using a smaller step size. Among them, the ones that can be taken To obtain more detailed current rescan data. , .

[0153] Step S206: Calculate the normal magnetic field second difference field and the tangential magnetic field second difference field between the initial scan data and the current rescan data of the preset points in the danger zone.

[0154] It should be noted that the normal magnetic field second difference field refers to the magnetic field parameters obtained by performing two difference processing on the initial and current rescan data of the normal magnetic field at the same preset point.

[0155] The tangential magnetic field second-difference field refers to the magnetic field parameters obtained by performing two differential processing on the initial and current rescan data of the tangential magnetic field at the same preset point.

[0156] In this embodiment of the invention, the second difference field between the current rescan data and the initial scan data is calculated, wherein the second difference field of the normal magnetic field is:

[0157] In the formula, This represents the normal magnetic field parameter of the current rescan data. This represents the normal magnetic field parameters of the initial rescan data.

[0158] The second difference field of the tangential magnetic field is:

[0159] In the formula, This represents the tangential magnetic field parameters of the current rescan data. This represents the tangential magnetic field parameters of the initial scan data.

[0160] Step S207: Calculate the latest magnetic field gradient magnitude of the normal magnetic field at the preset point using the normal magnetic field second difference field.

[0161] It should be noted that the normal magnetic field refers to the magnetic field component perpendicular to the surface of the reinforced concrete member being measured.

[0162] The latest magnetic field gradient magnitude refers to the real-time gradient magnitude calculated based on the second difference field of the normal magnetic field / tangential magnetic field.

[0163] In this embodiment of the invention, the gradient field of the normal magnetic field is calculated as a damage region localization index using the second difference field of the normal magnetic field. The specific calculation method is as follows:

[0164] In the formula, This represents the second difference field of the normal magnetic field.

[0165] Step S208: Calculate the latest magnetic field gradient magnitude of the tangential magnetic field at the preset point using the second difference field of the tangential magnetic field.

[0166] It should be noted that the tangential magnetic field refers to the magnetic field component that is parallel to the surface of the reinforced concrete component being tested.

[0167] In this embodiment of the invention, the gradient field of the tangential magnetic field second difference field is used as a damage area localization index. The specific calculation method is as follows:

[0168] In the formula, This represents the second difference field of the tangential magnetic field.

[0169] Step S209: Determine whether the latest magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field at each preset point is greater than the preset mutation threshold, and determine the damage location information based on the latest judgment result.

[0170] It should be noted that damage location information refers to information formed by integrating the specific spatial locations of all preset points of magnetic field anomalies.

[0171] In this embodiment of the invention, steps S2021 to S2026 are referred to define mutation criteria and damage area determination to obtain specific damage location information.

[0172] Step S210: Reinforce and repair the hazardous area according to the damage location information.

[0173] It should be noted that reinforcement and repair refers to the operation of taking technical measures such as strengthening and repair based on the location and severity of the damage and the performance requirements of the component.

[0174] In the embodiments of the present invention, see Figure 5 As shown, based on the location and extent of the damaged area obtained from the damage location information, at least one of the following reinforcement / repair measures is selected for artificial intervention, such as crack sealing / grouting for crack repair, and external composite materials (CFRP, FRCM, etc.) are used to reduce the stress of the steel reinforcement in the tension zone.

[0175] It is worth mentioning that this invention can achieve non-destructive testing / monitoring of damage, and is more sensitive to fatigue damage, enabling early warning of fatigue damage. Furthermore, this invention integrates fatigue damage detection, monitoring, assessment, and intervention, providing a new solution for structural maintenance and operation.

[0176] This embodiment also provides a fatigue damage early warning device for reinforced concrete structures. This device is used to implement the above embodiments and preferred embodiments, and details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0177] This embodiment provides a fatigue damage early warning device for reinforced concrete structures, such as... Figure 6 As shown, it includes: The scanning module 301 is used to scan the surface of the reinforced concrete component to be tested according to a preset magnetic field scanning path, obtain magnetic field data, and determine the magnetic field gradient based on the magnetic field change in the magnetic field data. The judgment module 302 is used to determine whether the gradient magnitude corresponding to the magnetic field gradient is greater than the preset abrupt change threshold, and to determine the dangerous area of ​​the reinforced concrete component to be tested based on the judgment result. Monitoring module 303 is used to monitor dangerous areas and collect magnetic field characteristic data of dangerous areas; The early warning module 304 is used to determine the structural fatigue damage and damage area of ​​the reinforced concrete component under test based on the evolution law of magnetic field characteristic data and to issue a corresponding early warning signal.

[0178] In some alternative implementations, the scanning module 301 includes: The scanning unit is used to scan each sampling point on the surface of the reinforced concrete member to be viewed according to a preset magnetic field scanning path, and to obtain the normal magnetic field component, tangential magnetic field component and corresponding position information of each sampling point. The preprocessing unit is used to perform noise reduction filtering preprocessing on the normal magnetic field component and the tangential magnetic field component to obtain magnetic field data; The normal change unit is used to calculate the change in the normal magnetic field by taking the normal magnetic field component of the magnetic field data and the normal magnetic field of the initial health state. The tangential change unit is used to calculate the tangential magnetic field change by using the tangential magnetic field component of the magnetic field data and the initial healthy state tangential magnetic field. The construction unit is used to construct a two-dimensional magnetic field distribution map by interpolating the normal magnetic field change, tangential magnetic field change, and corresponding location information of the sampling points. The solution unit is used to solve for the magnetic field gradient magnitudes corresponding to the normal and tangential magnetic fields at each sampling point based on the two-dimensional magnetic field distribution map.

[0179] In some optional implementations, the determination module 302 includes: The first judgment unit is used to determine whether the magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field of the sampling point is greater than the preset abrupt change threshold. The first mutation point unit is used to determine the sampling point as a mutation point if the mutation point is identified. The second judgment unit is used to determine whether the curve corresponding to the change in normal magnetic field or change in tangential magnetic field of the sampling point in the two-dimensional magnetic field distribution map has a peak or a zero-crossing point if the result is not found. The second mutation point unit is used to determine the sampling point as a mutation point if the mutation point is identified. Binding units are used to bind mutation points to obtain strip regions; The calculation unit is used to calculate the severity index of each strip region and determine the preset number of strip regions corresponding to the maximum severity index as danger zones.

[0180] In some alternative implementations, the monitoring module 303 includes: The setting unit is used to set up multiple magnetic probes in the hazardous area according to preset locations; The acquisition unit is used to acquire the normal magnetic field strength, tangential magnetic field strength, and residual magnetic induction intensity after unloading for a single cycle at each preset point through each magnetic probe, so as to obtain the magnetic field characteristic data of the dangerous area.

[0181] In some alternative implementations, the warning module 304 includes: The division unit is used to divide the acquisition time of magnetic field characteristic data by the magnetic probe into multiple time windows according to a preset time interval; The extraction unit is used to extract the minimum residual magnetic induction intensity after unloading for all single cycles within the time window, and obtain the characteristic value of the magnetic field induction intensity of the time window. The traversal unit is used to traverse the magnetic field induction intensity characteristic values ​​and corresponding timestamps of the entire time window of the acquisition time to obtain the scatter sequence of the magnetic probe. The fitting unit is used to perform least squares linear fitting on multiple consecutive scattered points of the scattered point sequence of each magnetic probe to obtain the slope of each magnetic probe. The growth unit is used to determine the relative growth rate of the slope based on the slopes of two adjacent magnetic probes; The third judgment unit is used to determine whether the relative growth rate of the slope corresponding to multiple consecutive time windows of the magnetic probe is greater than the preset warning threshold. The first early warning unit is used to determine if the reinforced concrete component under test has structural fatigue damage and to issue a corresponding early warning message if the condition is met. The fourth judgment unit is used to determine, if not, whether there is a preset number of magnetic probes whose relative growth rate of the slope corresponding to the time window of the magnetic probes is greater than the preset warning threshold. The second early warning unit is used to determine, if yes, that the reinforced concrete component under test has structural fatigue damage and a damaged area of ​​structural fatigue damage, and to issue corresponding early warning information.

[0182] In some alternative embodiments, the device includes: The repeated scanning unit is used to repeatedly scan each preset point in the danger zone according to a preset scanning step size to obtain the initial scan data and the current repeated scan data. The differential field unit is used to calculate the normal magnetic field second difference field and the tangential magnetic field second difference field between the initial scan data and the current rescan data of the preset points in the danger zone. The latest normal magnitude unit is used to calculate the latest magnetic field gradient magnitude of the normal magnetic field at a preset point using the normal magnetic field second difference field; The latest tangential magnitude unit is used to calculate the latest magnetic field gradient magnitude of the tangential magnetic field at a preset point using the second difference field of the tangential magnetic field; The positioning unit is used to determine whether the latest magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field at each preset point is greater than the preset mutation threshold, and to determine the damage positioning information based on the latest judgment result. The reinforcement and repair unit is used to reinforce and repair hazardous areas according to damage location information.

[0183] The fatigue damage early warning device for reinforced concrete structures provided in this embodiment of the invention can execute the fatigue damage early warning method for reinforced concrete structures provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method. Further functional descriptions of the above modules and units are the same as in the corresponding embodiments described above, and will not be repeated here.

[0184] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0185] The following is a detailed reference. Figure 7This diagram illustrates a structural schematic suitable for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 401, which can perform various appropriate actions and processes based on a program stored in read-only memory (ROM) 402 or a program loaded from memory 408 into random access memory (RAM) 403. RAM 403 also stores various programs and data required for the operation of the electronic device. The processor 401, ROM 402, and RAM 403 are interconnected via bus 404. Input / output (I / O) interface 405 is also connected to bus 404.

[0186] Typically, the following devices can be connected to I / O interface 405: input devices 406 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 407 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 408 including, for example, magnetic tapes, hard disks, etc.; and communication devices 409. Communication device 409 allows electronic devices to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 7 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0187] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 409, or installed from a memory 408, or installed from a ROM 402. When the computer program is executed by the processor 401, it performs the functions defined in the fatigue damage early warning method for reinforced concrete structures according to embodiments of the present invention.

[0188] Figure 7 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.

[0189] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the fatigue damage early warning method for reinforced concrete structures shown in the above embodiments is implemented.

[0190] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0191] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for early warning of fatigue damage in reinforced concrete structures, characterized in that, The method includes: Multiple sampling points of the reinforced concrete component to be tested are scanned according to a preset magnetic field scanning path to obtain magnetic field data, and the magnetic field gradient is determined based on the magnetic field change in the magnetic field data. Determine whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets the preset abrupt change condition, and determine the danger zone based on the determination result; The dangerous area is monitored, and magnetic field characteristic data of the dangerous area are collected; Based on the evolution of the magnetic field characteristic data, the structural fatigue damage and damage area of ​​the reinforced concrete component under test are determined and a corresponding early warning signal is issued.

2. The method according to claim 1, characterized in that, The process of scanning multiple sampling points of the reinforced concrete component under test according to a preset magnetic field scanning path to obtain magnetic field data, and determining the magnetic field gradient based on the magnetic field change in the magnetic field data, includes: The sampling points on the surface of the reinforced concrete member to be viewed are scanned according to the preset magnetic field scanning path to obtain the normal magnetic field component, tangential magnetic field component and corresponding position information of each sampling point. The normal magnetic field component and the tangential magnetic field component are subjected to noise reduction filtering preprocessing to obtain magnetic field data; The change in normal magnetic field is calculated using the normal magnetic field component of the magnetic field data and the normal magnetic field under the initial healthy state. The change in tangential magnetic field is calculated using the tangential magnetic field component of the magnetic field data and the initial healthy state tangential magnetic field. A two-dimensional magnetic field distribution map is constructed by interpolating the normal magnetic field change, tangential magnetic field change, and corresponding location information of the sampling points. Based on the two-dimensional magnetic field distribution map, the magnetic field gradient magnitudes corresponding to the normal magnetic field and tangential magnetic field at each sampling point are calculated.

3. The method according to claim 2, characterized in that, The step of determining whether the gradient magnitude or magnetic field change corresponding to the magnetic field gradient meets the preset abrupt change condition, and determining the danger zone based on the determination result, includes: Determine whether the magnitude of the magnetic field gradient corresponding to the normal magnetic field or tangential magnetic field at the sampling point is greater than a preset abrupt change threshold; If so, the sampling point is determined as a mutation point; If not, then determine whether the curves corresponding to the normal magnetic field change or tangential magnetic field change of the sampling points in the two-dimensional magnetic field distribution map have peaks or zero points. If so, the sampling point is determined as a mutation point; By combining the aforementioned mutation points, the banded regions are obtained; Calculate the severity index of each strip region, and determine the preset number of strip regions corresponding to the maximum severity index as danger zones.

4. The method according to claim 1, characterized in that, The monitoring of the hazardous area and the collection of magnetic field characteristic data of the hazardous area include: Multiple magnetic probes are installed in the hazardous area according to preset locations; The magnetic field characteristic data of the dangerous area are obtained by collecting the normal magnetic field strength, tangential magnetic field strength, and residual magnetic induction intensity after unloading for a single cycle at each preset point using the magnetic probes.

5. The method according to claim 4, characterized in that, The step of determining the structural fatigue damage and damage area of ​​the reinforced concrete component under test based on the evolution law of the magnetic field characteristic data and issuing a corresponding early warning signal includes: The magnetic probe's acquisition time of the magnetic field characteristic data is divided into multiple time windows according to a preset time interval; Extract the minimum residual magnetic flux density after unloading for all single cycles within the time window to obtain the magnetic flux density characteristic value of the time window; By iterating through all the time windows of the acquisition time and collecting the characteristic values ​​of the magnetic field induction intensity and the corresponding timestamps, a scatter sequence of the magnetic probe is obtained. The slope of each magnetic probe is obtained by performing least squares linear fitting on multiple consecutive scattered points of the scattered point sequence of each magnetic probe. The relative growth rate of the slope is determined based on the slopes of any two adjacent magnetic probes. Determine whether the relative growth rate of the slope corresponding to multiple consecutive time windows of the magnetic probe is greater than a preset warning threshold; If so, it is determined that the reinforced concrete component under test has structural fatigue damage, and a corresponding warning message is issued; If not, then determine whether there is a preset number of magnetic probes whose relative growth rate of slope corresponding to the time window of the magnetic probe is greater than a preset warning threshold. If so, the test reinforced concrete component is determined to have structural fatigue damage and the damaged area of ​​the structural fatigue damage, and a corresponding warning message is issued.

6. The method according to claim 1, characterized in that, The method further includes: The preset points in the danger zone are repeatedly scanned according to the preset scanning step size to obtain the initial scan data and the current rescan data. Calculate the normal magnetic field second difference field and the tangential magnetic field second difference field between the initial scan data and the current rescan data of the preset points in the dangerous area; The latest magnetic field gradient magnitude of the normal magnetic field at the preset point is calculated using the second difference field of the normal magnetic field. The latest magnetic field gradient magnitude of the tangential magnetic field at the preset point is calculated using the second difference field of the tangential magnetic field. Determine whether the latest magnetic field gradient magnitude corresponding to the normal magnetic field or tangential magnetic field at each preset point is greater than the preset mutation threshold, and determine the damage location information based on the latest determination result; The dangerous area was reinforced and repaired according to the damage location information.

7. A fatigue damage early warning device for reinforced concrete structures, characterized in that, The device includes: The scanning module is used to scan the surface of the reinforced concrete component to be tested according to a preset magnetic field scanning path, obtain magnetic field data, and determine the magnetic field gradient based on the magnetic field change in the magnetic field data. The judgment module is used to determine whether the gradient magnitude value corresponding to the magnetic field gradient is greater than a preset abrupt change threshold, and to determine the dangerous area of ​​the reinforced concrete component to be tested based on the judgment result. The monitoring module is used to monitor the dangerous area and collect magnetic field characteristic data of the dangerous area; The early warning module is used to determine the structural fatigue damage and damage area of ​​the reinforced concrete component under test based on the evolution law of the magnetic field characteristic data and to issue a corresponding early warning signal.

8. An electronic device, characterized in that, include: The system includes a memory and a processor, which are interconnected. The memory stores computer instructions, and the processor executes the computer instructions to perform the fatigue damage early warning method for reinforced concrete structures as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a computer to execute the fatigue damage early warning method for reinforced concrete structures according to any one of claims 1 to 6.

10. A computer program product, characterized in that, Includes computer instructions, which are used to cause a computer to perform fatigue damage early warning for reinforced concrete structures as described in any one of claims 1 to 6.

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