A method for detecting the thickness of a concrete anticorrosion coating of a power transmission and transformation project foundation on site

Abstract

The application relates to the technical field of thickness detection, in particular to a concrete anticorrosion coating thickness field detection method for a power transmission and transformation engineering foundation, which comprises the following steps: collecting ultrasonic echo data of each measuring point in an anticorrosion coating measuring area; obtaining a first wave amplitude, a bottom wave amplitude and a clutter amplitude in the ultrasonic echo data; constructing an abnormality evaluation coefficient of each measuring point according to the size of the clutter amplitude of each measuring point, the attenuation degree of the bottom wave amplitude, the waveform difference degree between adjacent bottom waves, the bottom wave amplitude difference in the ultrasonic echo data of each measuring point and other measuring points, and the time interval difference of adjacent bottom waves; extracting effective measuring points according to the deviation degree of the abnormality evaluation coefficient of each measuring point relative to all other measuring points; and calculating the coating thickness of the anticorrosion coating measuring area by using the ultrasonic echo data of all the effective measuring points. The application improves the accuracy of coating thickness detection by eliminating abnormal ultrasonic echo data when calculating the coating thickness.

Description

Technical Field

[0001] This application relates to the field of thickness detection technology, specifically to a method for on-site detection of the thickness of concrete anti-corrosion coatings for power transmission and transformation engineering foundations. Background Technology

[0002] The foundations of power transmission and transformation projects are typically made of concrete. Concrete structures are susceptible to corrosion under certain environments, especially saline environments, which poses a serious threat to their structural integrity and service life. Currently, methods to address the corrosion and aging failure of concrete in power transmission and transformation projects include upgrading the concrete grade, adding admixtures, and applying anti-corrosion coatings. Among these, anti-corrosion coatings are one of the most effective methods for concrete protection due to their low cost and simple construction process.

[0003] The thickness of concrete anti-corrosion coatings is one of the key factors affecting their durability and stability. To ensure coating effectiveness and improve construction quality, accurate thickness measurement is essential. For non-metallic substrates, coating thickness is typically measured using the ultrasonic method, which calculates the coating thickness by detecting the round-trip time of ultrasonic waves within the coating material and combining this with the known sound velocity in the material. However, when using ultrasonic coating thickness gauges to measure the thickness of concrete anti-corrosion coatings, problems arise due to the roughness, porosity, and poor coupling of the concrete substrate. These factors cause scattering and attenuation of the ultrasonic signal, directly affecting the accuracy of the thickness measurement. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a method for on-site testing of the thickness of the concrete anti-corrosion coating on the foundation of power transmission and transformation projects, thereby resolving the existing issues.

[0005] The present application discloses a method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations, which adopts the following technical solution:

[0006] One embodiment of this application provides a method for on-site detection of the thickness of the anti-corrosion coating on the concrete foundation of a power transmission and transformation project. The method includes the following steps:

[0007] Ultrasonic echo data were collected at each measuring point within the measurement area of ​​the anti-corrosion coating.

[0008] The amplitude of the first wave, the amplitude of the bottom wave, and the amplitude of clutter are obtained from the ultrasonic echo data of each measuring point. Based on the magnitude of the clutter amplitude, the attenuation degree of the bottom wave amplitude, and the waveform difference between adjacent bottom waves, the first anomaly factor of each measuring point is constructed.

[0009] By analyzing the degree of difference between the amplitude of the bottom wave in the ultrasound echo data of each measuring point and other measuring points, as well as the degree of difference in the time interval between adjacent bottom waves, a second anomaly factor is constructed for each measuring point. Combined with the first anomaly factor, an anomaly evaluation coefficient is constructed for each measuring point to characterize the comprehensive anomaly degree of the ultrasound echo data of each measuring point.

[0010] Based on the degree of deviation of the anomaly evaluation coefficient of each measuring point from the anomaly evaluation coefficients of all other measuring points, valid measuring points are extracted from all measuring points, and then the coating thickness of the anti-corrosion coating measurement area is calculated using the ultrasonic echo data of all valid measuring points.

[0011] Preferably, the method for obtaining the first wave amplitude, the bottom wave amplitude, and the clutter amplitude in the ultrasonic echo data of each measuring point is as follows:

[0012] The ultrasonic echo data at each measuring point are curve-fitted to obtain the maximum point in the fitted curve.

[0013] The maximum value among all maxima is recorded as the first wave amplitude.

[0014] The maximum value exceeding the preset segmentation threshold is recorded as the bottom wave amplitude value;

[0015] The maximum value that is less than or equal to the preset segmentation threshold is recorded as the clutter amplitude.

[0016] Preferably, the ratio of the amplitude of each bottom wave to the amplitude of the first wave in the ultrasonic echo data of each measuring point is statistically analyzed; the bottom wave attenuation significance value of each measuring point is constructed using this ratio, wherein the bottom wave attenuation significance value is negatively correlated with the ratio.

[0017] Preferably, the DTW distance between the fitted curves corresponding to the peak-to-bottom width range of all adjacent bottom wave amplitudes in the ultrasonic echo data of each measuring point is calculated, and the mean of all DTW distances is recorded as the waveform difference coefficient of each measuring point.

[0018] Preferably, the method for constructing the first anomaly factor for each measuring point is as follows:

[0019] Calculate the root mean square value of all clutter amplitudes at each measuring point;

[0020] The first anomaly factor at each measuring point is positively correlated with the root mean square value, the significant value of the bottom wave attenuation, and the waveform difference coefficient.

[0021] Preferably, the method for constructing the second anomaly factor at each measuring point is as follows:

[0022] Obtain the wave crest sequence and bottom wave time interval sequence at each measuring point;

[0023] Calculate the Pearson correlation coefficient between the peak sequences of each measuring point and all other measuring points;

[0024] Calculate the Pearson correlation coefficient between each measuring point and the bottom wave time interval sequences of all other measuring points;

[0025] The second abnormal factor at each measurement point is negatively correlated with both of the above Pearson correlation coefficients.

[0026] Preferably, the peak sequence and bottom wave time interval sequence of each measuring point refer to the sequence formed by the time intervals between all bottom wave amplitudes and all adjacent bottom wave amplitudes in the ultrasonic echo data of each measuring point, arranged in their positional order.

[0027] Preferably, the anomaly evaluation coefficient of each measuring point is positively correlated with both the first anomaly factor and the second anomaly factor.

[0028] Preferably, the method for extracting the effective measurement points is as follows:

[0029] The anomaly evaluation coefficients of all measurement points are used as input to the SOS anomaly detection algorithm, and the anomaly probability value of the anomaly evaluation coefficient of each measurement point is output.

[0030] Measurement points with an anomaly probability value less than or equal to a preset anomaly threshold are recorded as valid measurement points.

[0031] Preferably, the method for calculating the coating thickness in the measurement area of ​​the anti-corrosion coating is as follows:

[0032] The coating thickness at each effective measuring point is calculated by using the time interval between the first wave and the bottom wave in the ultrasonic echo data of each effective measuring point.

[0033] The average coating thickness at all valid measurement points is taken as the coating thickness of the anti-corrosion coating measurement area.

[0034] This application has at least the following beneficial effects:

[0035] This application addresses the problem of scattering and attenuation of ultrasonic echo data caused by factors such as the roughness, porosity, and poor coupling of the concrete matrix during ultrasonic testing, which affects the accuracy of coating thickness measurement. By analyzing clutter interference, abnormal attenuation of the backwave amplitude, and waveform distortion characteristics in the ultrasonic echo data at each measuring point, a first anomaly factor is constructed to provide a preliminary assessment of the ultrasonic echo data quality. Furthermore, considering the impact of spatial inhomogeneity of the concrete matrix on thickness measurement, the differences in ultrasonic echo data from different measuring points are analyzed to construct a second anomaly factor, which further assesses the quality of the ultrasonic echo data at each measuring point. Finally, an anomaly evaluation coefficient is constructed to comprehensively evaluate the quality of the ultrasonic echo data at each measuring point. Based on the obtained anomaly evaluation coefficient, ultrasonic echo data from measuring points with significant anomalies are removed, and the coating thickness is then calculated using the ultrasonic echo data from the valid measuring points. Its advantage lies in effectively reducing clutter and anomaly interference caused by the aforementioned factors, thereby improving the accuracy and reliability of coating thickness detection. Attached Figure Description

[0036] Figure 1 A flowchart illustrating the steps of an on-site method for detecting the thickness of an anti-corrosion coating on the foundation of a power transmission and transformation project, as provided in this application.

[0037] Figure 2 A flowchart for obtaining the anomaly evaluation coefficients for each measurement point provided in this application. Detailed Implementation

[0038] This application provides an embodiment of a method for on-site testing of the thickness of the anti-corrosion coating on the concrete foundation of a power transmission and transformation project. For details, please refer to [link to relevant documentation]. Figure 1 The method includes the following steps:

[0039] S1: Collect ultrasonic echo data for each measuring point within the measurement area of ​​the anti-corrosion coating.

[0040] This application employs silane and siloxane-based penetrating coatings for concrete corrosion protection. These coatings can penetrate into the pores of concrete and cover the pore surface through a chemical reaction, achieving excellent corrosion protection. An ultrasonic coating thickness gauge is used to detect the thickness of the anti-corrosion coating; this instrument is based on the pulse-echo method for non-destructive measurement.

[0041] Before on-site testing, the condition of the substrate should be confirmed, such as whether the surface is completely cured, whether there are serious surface pores, and to avoid areas with obvious defects as much as possible. At the same time, the ultrasonic coating thickness gauge should be checked, such as whether the instrument's range and accuracy meet the testing requirements for coating thickness. The detection accuracy should not be greater than 0.01 mm, and the range should not be less than 120% of the designed coating thickness.

[0042] During on-site testing, several measuring points are evenly set on the surface of the anti-corrosion coating. A coupling agent (such as gel) is applied between the probe and the surface of the anti-corrosion coating to ensure effective transmission of ultrasonic signals. Subsequently, the probe of the ultrasonic coating thickness gauge is pressed vertically against the surface of each measuring point in sequence, applying an appropriate and constant force to avoid tilting or slipping, thereby acquiring ultrasonic echo data for each measuring point. In this embodiment, the acquisition time of ultrasonic echo data for each measuring point is set to 100 microseconds.

[0043] S2: Obtain the first wave amplitude, bottom wave amplitude, and clutter amplitude from the ultrasonic echo data of each measuring point. Based on the magnitude of the clutter amplitude, the attenuation degree of the bottom wave amplitude, and the waveform difference between adjacent bottom waves, construct the first anomaly factor for each measuring point.

[0044] The quality of the acquired ultrasonic echo data is crucial to the accuracy of thickness measurement. However, interference from the roughness, porosity, and poor coupling of concrete surfaces can easily lead to unstable or abnormal ultrasonic echoes, affecting measurement accuracy and thus reducing the reliability of the thickness measurement results. Therefore, it is necessary to analyze the quality of the ultrasonic echo data.

[0045] Specifically, the acquired ultrasonic echo data includes a first wave and multiple back waves. The first wave is the reflected signal generated when the ultrasonic wave enters the surface of the object being tested from the probe, while the back waves are the signals reflected back after the ultrasonic wave propagates to the back of the material. Furthermore, the ultrasonic wave undergoes multiple reflections between the upper and lower interfaces of the coating material, thus forming multiple back waves. Under conditions of smooth substrate and good coupling, the ultrasonic echo data acquired exhibits stable echo amplitudes, regular waveforms, and relatively consistent patterns.

[0046] Concrete matrix itself is a rough material with significant attenuation. The numerous micropores and microcracks within it cause severe scattering and absorption of ultrasonic waves during propagation, leading to energy attenuation and transmission into the substrate. This results in jitter, distortion, and a large amount of fine clutter interference in the ultrasonic echo data, easily affecting measurement accuracy. Therefore, taking the ultrasonic echo data at the h-th measurement point as an example, the least squares method is used for curve fitting to obtain a fitted curve. The derivative calculation method is used to extract the maximum points of this fitted curve. The maximum values ​​corresponding to the first wave and each bottom wave position are significantly higher than other interference extreme values, and the maximum value corresponding to the first wave is higher than the maximum values ​​corresponding to each bottom wave position. Therefore, the maximum value with the largest value among all maximum values ​​is marked as the first wave amplitude. Then, the mean of all other maximum values ​​except the first wave is calculated and recorded as the preset segmentation threshold; maximum values ​​greater than the preset segmentation threshold are recorded as bottom wave amplitudes; and maximum values ​​less than or equal to the preset segmentation threshold are recorded as clutter amplitudes. These clutters are mainly caused by scattering and diffraction of ultrasonic waves due to micropores, microcracks, and heterogeneous interfaces within the concrete.

[0047] Then, the root mean square (RMS) value of all clutter amplitudes at the h-th measurement point is calculated; the larger the value, the greater the clutter amplitude. Next, using the first wave amplitude as the normalization benchmark to eliminate the influence of differences in transmission energy under different detection conditions, the ratio of the above RMS value to the first wave amplitude is used as the clutter interference coefficient at the h-th measurement point, reflecting the degree of clutter interference on the ultrasonic echo data at the h-th measurement point; the larger the value, the greater the degree of clutter interference on the ultrasonic echo data.

[0048] Furthermore, the waveform changes of each bottom wave obtained under the condition of smooth substrate and good coupling are regular, and the peak of the wave shows a stable and slow gradual decrease. During the reflection of the ultrasonic wave in the middle of the anti-corrosion coating, the energy will be attenuated due to the rough surface and porous structure of the concrete substrate, resulting in a significant decrease in the amplitude of the bottom wave.

[0049] Therefore, based on the attenuation degree of the bottom wave amplitude in the ultrasonic echo data of each measuring point, a significant value for bottom wave attenuation is constructed to characterize the significance of the abnormal attenuation characteristics of the bottom wave amplitude in the ultrasonic echo data of each measuring point. The method for constructing the significant value for bottom wave attenuation is as follows: the ratio of each bottom wave amplitude to the first wave amplitude in the ultrasonic echo data of each measuring point is calculated; the significant value for bottom wave attenuation is negatively correlated with the ratio.

[0050] In this embodiment, the formula for calculating the significant value of the bottom wave attenuation at the h-th measuring point is as follows: In the formula, The significant value of the bottom wave attenuation at the h-th measuring point; This represents the total number of bottom waves in the ultrasonic echo data at the h-th measurement point. Let be the amplitude of the i-th bottom wave in the ultrasonic echo data of the h-th measuring point; This represents the amplitude of the first wave in the ultrasonic echo data from the h-th measurement point. The obtained... The larger the value, the more significant the abnormal attenuation of the bottom wave amplitude in the ultrasonic echo data of the h-th measurement point.

[0051] Furthermore, under regular waveform changes, the bottom waves exhibit a high degree of morphological similarity. Reflection caused by rough surfaces distorts the waveform shape, disrupting this similarity. Therefore, the DTW distance between the fitted curves within the peak-to-base width range corresponding to the amplitudes of all adjacent bottom waves in the ultrasonic echo data of the h-th measurement point is calculated. The average of all DTW distances is then recorded as the waveform difference coefficient for the h-th measurement point. The larger the waveform difference coefficient, the lower the morphological similarity between adjacent bottom wave waveforms in the ultrasonic echo data of the h-th measurement point, and the more pronounced the overall distortion characteristics. The acquisition of peak-to-base width and the calculation of DTW distance are well-known techniques, and the specific process will not be elaborated further.

[0052] In a preferred embodiment, a first anomaly factor is constructed for each measuring point based on the magnitude of clutter amplitude, the attenuation degree of the bottom wave amplitude, and the waveform difference between adjacent bottom waves. This factor characterizes the degree of clutter interference and bottom wave anomaly in the ultrasonic echo data at each measuring point. The method for constructing the first anomaly factor for each measuring point is as follows: calculate the root mean square value of all clutter amplitudes at each measuring point; obtain the significant value of bottom wave attenuation and the waveform difference coefficient for each measuring point; the first anomaly factor for each measuring point is positively correlated with the root mean square value, the significant value of bottom wave attenuation, and the waveform difference coefficient.

[0053] In this embodiment, the first anomaly factor of the h-th measurement point is denoted as... The formula is as follows: In the formula, The first anomaly factor at the h-th measurement point; The clutter interference coefficient at the h-th measurement point; The significant value of the bottom wave attenuation at the h-th measuring point; The waveform difference coefficient at the h-th measurement point; This is the hyperbolic tangent function, used for normalization.

[0054] income The larger the value, the greater the noise interference in the ultrasonic echo data of the h-th measurement point, and the more significant the abnormal attenuation of the bottom wave amplitude and waveform distortion characteristics. In this case, it is more difficult to effectively identify the time difference of ultrasonic wave propagation in the coating, which will reduce the accuracy of coating thickness measurement.

[0055] S3: By analyzing the degree of difference between the amplitude of the bottom wave in the ultrasonic echo data of each measuring point and other measuring points, as well as the degree of difference in the time interval between adjacent bottom waves, a second anomaly factor is constructed for each measuring point. Combined with the first anomaly factor, an anomaly evaluation coefficient is constructed for each measuring point to characterize the comprehensive anomaly degree of the ultrasonic echo data of each measuring point.

[0056] Furthermore, the concrete substrate exhibits significant spatial inhomogeneity. This inhomogeneity leads to substantial differences in ultrasonic echo data at different measuring points, thereby affecting the reliability and accuracy of coating thickness measurements. Under conditions of smooth substrate and good coupling, the ultrasonic echo data at different measuring points are more similar, manifested in the consistency of the base wave amplitude and the time interval between adjacent peaks. However, in cases with severe ultrasonic scattering and absorption, readings at different locations of the ultrasonic echo data may jump, affecting the accurate measurement of thickness. For example, there may be significant differences in the base wave amplitude at different locations, and the consistency of the time interval between adjacent peaks may be poor.

[0057] Therefore, taking the ultrasound echo data from the h-th measurement point as an example, the sequence of all base wave amplitudes in the ultrasound echo data from the h-th measurement point, arranged in their positional order, is denoted as the peak sequence of the h-th measurement point. Subsequently, the Pearson correlation coefficients between the peak sequences of the h-th measurement point and those of all other measurement points are calculated, and the mean of all Pearson correlation coefficients is denoted as... The result The larger the value, the more consistent the bottom echo amplitude of that measurement point is with all other measurement points. Additionally, the time intervals between all adjacent bottom echo amplitudes in the ultrasonic echo data of the h-th measurement point are calculated, and all the resulting time intervals are arranged in chronological order and denoted as the bottom echo time interval sequence of the h-th measurement point. Then, the Pearson correlation coefficients between the bottom echo time interval sequences of the h-th measurement point and all other measurement points are calculated, and the mean of all Pearson correlation coefficients is denoted as... The result The larger the value, the stronger the consistency between the bottom wave time interval of that measuring point and the bottom wave time intervals of other measuring points. It should be noted that in the calculation of the Pearson correlation coefficient, if the two input sequences have different lengths, the end data of the longer sequence is deleted until the length of the longer sequence equals the length of the shorter sequence before calculation.

[0058] In a preferred embodiment, a second anomaly factor is constructed for each measuring point by analyzing the differences in baseline amplitude and time interval between adjacent baseline waves in the ultrasonic echo data of each measuring point and other measuring points. This second anomaly factor characterizes the differences in baseline amplitude and time interval between each measuring point and other measuring points. The method for constructing the second anomaly factor for each measuring point is as follows: obtaining the peak sequence and baseline time interval sequence of each measuring point; calculating the Pearson correlation coefficient between the peak sequences of each measuring point and all other measuring points; calculating the Pearson correlation coefficient between the baseline time interval sequences of each measuring point and all other measuring points; the second anomaly factor for each measuring point is negatively correlated with both of the above Pearson correlation coefficients.

[0059] In this embodiment, the second anomaly factor of the h-th measurement point is denoted as... Its specific expression is: In the formula, The second anomaly factor at the h-th measurement point; The mean of the Pearson correlation coefficients between the peak sequences of the h-th measuring point and all other measuring points; The mean of the Pearson correlation coefficients between the h-th measuring point and the bottom wave time interval sequences of all other measuring points; It is an exponential function with the natural constant e as its base.

[0060] income The larger the value, the more inconsistent the bottom wave amplitude and the more inconsistent the bottom wave time interval are between the ultrasonic echo data of the h-th measuring point and other measuring points. This indicates that the ultrasonic echo data of the h-th measuring point is more affected by the spatial non-uniformity of the concrete matrix properties during the anti-corrosion coating thickness detection process.

[0061] Preferably, an anomaly assessment coefficient is constructed for each measuring point based on a first anomaly factor and a second anomaly factor. This coefficient characterizes the overall anomaly degree of the ultrasound echo data at each measuring point. The anomaly assessment coefficient for each measuring point is positively correlated with both the first and second anomaly factors. The flowchart for obtaining the anomaly assessment coefficient for each measuring point is shown below. Figure 2 As shown.

[0062] In this embodiment, the anomaly evaluation coefficient of the h-th measuring point is denoted as... The formula is as follows: In the formula, The anomaly assessment coefficient for the h-th measurement point; The first anomaly factor at the h-th measurement point; It is the second anomaly factor of the h-th measurement point.

[0063] income The larger the value, the lower the quality of the ultrasonic echo data at the h-th measurement point, and the less reliable the coating thickness measurement result obtained using the ultrasonic echo data at that measurement point.

[0064] S4: Based on the degree of deviation of the anomaly evaluation coefficient of each measuring point from the anomaly evaluation coefficients of all other measuring points, extract the effective measuring points from all measuring points, and then use the ultrasonic echo data of all effective measuring points to calculate the coating thickness of the anti-corrosion coating measurement area.

[0065] Furthermore, since the quality of ultrasonic echo data directly affects the accuracy of thickness measurement, it is necessary to discard the ultrasonic echo data of measurement points with poor quality in the anti-corrosion coating measurement area based on the above evaluation results, and retain the valid detection data.

[0066] Specifically, in the detection of anti-corrosion coating thickness, the more severe the influence of factors such as the roughness, porosity, and poor coupling of the concrete substrate on each measuring point, the larger the anomaly evaluation coefficient of the corresponding measuring point will be. Therefore, the anomaly evaluation coefficient of the corresponding measuring point will deviate significantly from that of other measuring points. To address this, the anomaly evaluation coefficients of all measuring points are used as input to the SOS anomaly detection algorithm, and the output is the anomaly probability value of the anomaly evaluation coefficient for each measuring point, with a value range of [0,1]. This value reflects the probability that each measuring point is an anomaly point relative to other measuring points. In this embodiment, the preset anomaly threshold is 0.9. If the anomaly probability value of the anomaly evaluation coefficient of any measuring point is greater than the preset anomaly threshold, it indicates that the ultrasonic echo data quality of that measuring point is poor, and the measuring point is determined to be an anomaly measuring point, and its ultrasonic echo data is abnormal data and will not participate in the coating thickness calculation; conversely, if the value is less than the preset threshold, the measuring point is determined to be a valid measuring point, and its ultrasonic echo data is normal data and will participate in the coating thickness calculation.

[0067] Furthermore, the coating thickness is calculated and output using ultrasonic echo data from effective measurement points. Specifically, the coating thickness at each measurement point is calculated using the time interval between the first wave and the bottom wave in the ultrasonic echo data from each effective measurement point. The method for calculating the coating thickness is a well-known technique, and the specific process will not be elaborated further. Subsequently, the average coating thickness of all effective measurement points in the secondary measurement area of ​​the anti-corrosion coating is taken as the coating thickness measurement result for the anti-corrosion coating measurement area. The obtained coating thickness measurement result can accurately represent the actual thickness of the anti-corrosion coating measurement area.

Claims

1. A method for on-site testing of the thickness of the anti-corrosion coating on the foundation of a power transmission and transformation project, characterized in that, The method includes the following steps: Ultrasonic echo data were collected at each measuring point within the measurement area of ​​the anti-corrosion coating. The amplitude of the first wave, the amplitude of the bottom wave, and the amplitude of clutter are obtained from the ultrasonic echo data of each measuring point. Based on the magnitude of the clutter amplitude, the attenuation degree of the bottom wave amplitude, and the waveform difference between adjacent bottom waves, the first anomaly factor of each measuring point is constructed. By analyzing the degree of difference between the amplitude of the bottom wave in the ultrasound echo data of each measuring point and other measuring points, as well as the degree of difference in the time interval between adjacent bottom waves, a second anomaly factor is constructed for each measuring point. Combined with the first anomaly factor, an anomaly evaluation coefficient is constructed for each measuring point to characterize the comprehensive anomaly degree of the ultrasound echo data of each measuring point. Based on the degree of deviation of the anomaly evaluation coefficient of each measuring point from the anomaly evaluation coefficients of all other measuring points, valid measuring points are extracted from all measuring points, and then the coating thickness of the anti-corrosion coating measurement area is calculated using the ultrasonic echo data of all valid measuring points.

2. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The methods for obtaining the first wave amplitude, bottom wave amplitude, and clutter amplitude in the ultrasonic echo data of each measuring point are as follows: The ultrasonic echo data at each measuring point are curve-fitted to obtain the maximum points in the fitted curve. The maximum value among all maxima is recorded as the first wave amplitude. The maximum value exceeding the preset segmentation threshold is recorded as the bottom wave amplitude value; The maximum value that is less than or equal to the preset segmentation threshold is recorded as the clutter amplitude.

3. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The ratio of the amplitude of each bottom wave to the amplitude of the first wave in the ultrasonic echo data of each measuring point is statistically analyzed; the bottom wave attenuation significance value of each measuring point is constructed using this ratio, wherein the bottom wave attenuation significance value is negatively correlated with the ratio.

4. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 3, characterized in that, Calculate the DTW distance between the fitted curves within the peak-to-bottom width range corresponding to all adjacent bottom wave amplitudes in the ultrasonic echo data of each measuring point, and record the mean of all DTW distances as the waveform difference coefficient of each measuring point.

5. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 4, characterized in that, The method for constructing the first anomaly factor for each measuring point is as follows: Calculate the root mean square value of all clutter amplitudes at each measuring point; The first anomaly factor at each measuring point is positively correlated with the root mean square value, the significant value of the bottom wave attenuation, and the waveform difference coefficient.

6. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The method for constructing the second anomaly factor at each measuring point is as follows: Obtain the wave crest sequence and bottom wave time interval sequence at each measuring point; Calculate the Pearson correlation coefficient between the peak sequences of each measuring point and all other measuring points; Calculate the Pearson correlation coefficient between each measuring point and the bottom wave time interval sequences of all other measuring points; The second abnormal factor at each measurement point is negatively correlated with both of the above Pearson correlation coefficients.

7. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 6, characterized in that, The peak sequence and bottom wave time interval sequence of each measuring point refer to the sequence composed of all bottom wave amplitudes and the time intervals between all adjacent bottom wave amplitudes in the ultrasonic echo data of each measuring point, arranged in their positional order.

8. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The anomaly assessment coefficients of each measurement point are positively correlated with both the first anomaly factor and the second anomaly factor.

9. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The method for extracting the effective measurement points is as follows: The anomaly evaluation coefficients of all measurement points are used as input to the SOS anomaly detection algorithm, and the anomaly probability value of the anomaly evaluation coefficient of each measurement point is output. Measurement points with an anomaly probability value less than or equal to a preset anomaly threshold are recorded as valid measurement points.

10. The method for on-site testing of the thickness of the concrete anti-corrosion coating for power transmission and transformation engineering foundations as described in claim 1, characterized in that, The method for calculating the coating thickness in the measurement area of ​​the anti-corrosion coating is as follows: The coating thickness at each effective measuring point is calculated by using the time interval between the first wave and the bottom wave in the ultrasonic echo data of each effective measuring point. The average coating thickness at all valid measurement points is taken as the coating thickness of the anti-corrosion coating measurement area.

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