Reinforced concrete foundation corrosion detection method and system based on microwave transmission method

Abstract

The present invention discloses a method and system for detecting the corrosion of reinforced concrete foundations for power transmission and transformation based on the microwave transmission method. Step S1: Determine the scanning frequency f of the microwave signal source and the rectangular waveguide, and obtain the transmission coefficient S at the corresponding scanning frequency f, and construct a reference value query unit; Step S2: Obtain the transmission coefficient S in the manner of Step S1, and construct a test value query unit; Step S3: Determine whether the steel bars are corroded by comparing the values at the corresponding positions of S and S; Step S4: The data comparison unit respectively retrieves the mapping relationship curves of the scanning frequency and the transmission coefficient in the reference value query unit and the test value query unit, and determines the corrosion parameters of the steel bars by comparing the curves f(x1) and f(x2). This solution uses microwaves as the signal source, initially determines the corrosion location through the difference between the incident signal and the transmitted signal, considers the corrosion area and corrosion depth, and further determines the specific corrosion degree of the steel bars, so that the detection efficiency and accuracy are significantly improved. 0 21 of the reference value, and construct a reference value query unit; Step S2: Obtain the transmission coefficient S in the manner of Step S1 1 21 ; and construct a test value query unit; Step S3: Determine whether the steel bars are corroded by comparing S 0 21 and S 1 21 at the corresponding positions; Step S4: The data comparison unit respectively retrieves the mapping relationship curves of the scanning frequency and the transmission coefficient in the reference value query unit and the test value query unit, and determines the corrosion parameters of the steel bars by comparing the curves f(x1) and f(x2). This solution uses microwaves as the signal source, initially determines the corrosion location through the difference between the incident signal and the transmitted signal, considers the corrosion area and corrosion depth, and further determines the specific corrosion degree of the steel bars, so that the detection efficiency and accuracy are significantly improved.

Description

Technical Field

[0001] The present invention relates to the field of engineering quality inspection, and in particular to a reinforced concrete foundation corrosion inspection method and system based on a microwave transmission method. Background Art

[0002] In recent years, my country's power industry has continued to develop, and the mileage of power transmission line construction has increased rapidly. In industrially heavily polluted areas and coastal areas, the corrosion problem of reinforced concrete foundations for power transmission and transformation has become increasingly prominent. Once the tower base collapses due to corrosion, it will seriously threaten the safety of the line.

[0003] At present, the common corrosion detection methods for reinforced concrete structures are mainly: X-ray irradiation method, electrochemical noise method, etc. The principle of X-ray irradiation method is: the energy of photons in X-rays is much greater than that of visible light, and can better penetrate objects that visible light cannot penetrate. At the same time, it will undergo complex changes with the object being tested to produce fluorescence. In the detection, the photosensitivity of the film can be used to detect the intensity of the transmitted X-rays to determine whether there are defects. Although X-ray detection is widely used, it also has a series of disadvantages: X-rays generally cause harm to the human body and produce some side effects; when using photographic detection, fixer is required, which is not easy to recycle and will cause harm to the environment; the detection speed is slow and the cost is high. Electrochemical noise detection belongs to electrochemical methods, which are contact measurements, and are relatively complex. There are problems such as lack of accuracy and long data processing time. Therefore, proposing an effective corrosion detection and evaluation method has important engineering practical significance for improving the operating reliability of power transmission and transformation equipment. Summary of the invention

[0004] The purpose of the present invention is to propose a reinforced concrete foundation corrosion detection method and system based on the microwave transmission method. The signal source generates a microwave signal, and the corrosion situation and the foundation corrosion position are preliminarily determined by the difference between the incident signal and the transmission signal. Furthermore, by comparing the difference between the transmission coefficient of the corroded steel bar and the transmission coefficient of the uncorroded steel bar, the corrosion area and the corrosion depth are taken into consideration, and the specific corrosion degree of the steel bar is comprehensively determined. Compared with the traditional method, the detection efficiency and accuracy are significantly improved.

[0005] In order to achieve the above technical purpose, the present invention provides a technical solution, which is a method for detecting corrosion of reinforced concrete foundation of power transmission and transformation based on microwave transmission method, comprising the following steps:

[0006] Step S1: The microwave signal source and the rectangular waveguide transmit microwave signals to the uncorroded reinforced concrete foundation of the power transmission and transformation, and determine the scanning frequency of the microwave signal source and the rectangular waveguide. f ,remember: f=(f1, f1,···, fn) , get the corresponding scanning frequency f The transmission coefficient under S 021 The baseline value is: S 0 21 =( S 01 21 ，S 02 21 ，···，S 0n 21 );Construct a benchmark value query unit;

[0007] Step S2: using a rectangular waveguide to periodically scan the frequency f Scan the reinforced concrete foundation of power transmission and transformation to obtain the transmission coefficient S 1 21 ;remember: S 1 21 =( S 11 21 ，S 12 21 ，···，S 1n 21 );Build a test value query unit;

[0008] Step S3: By comparing S 0 21 and S 1 21 The size of the value at the corresponding position is used to determine whether the steel bar is corroded; if S 1 21 The value at the corresponding position is less than S 0 21 The value at the corresponding position indicates that the steel bar has been corroded, otherwise it has not been corroded;

[0009] Step S4: The data comparison unit retrieves the fitting curves of the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and uses the curves f ( x 1) and f ( x 2) to determine the corrosion parameters of the steel bars.

[0010] In this scheme, a reference value query unit is first constructed, and a microwave incident signal is transmitted to the non-corroded reinforced concrete foundation of the power transmission and transformation through a rectangular waveguide transmitting probe, and a rectangular waveguide receiving probe receives the transmission signal to realize horizontal transmission scanning of the reinforced concrete structure and obtainS 0 21 The transmission coefficient and S 0 21 The reference value is recorded in the reference value query unit, and the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the foundation is recorded; secondly, a test value query unit is constructed, and the method is the same as above; by checking the deviation of the transmission coefficient, the corrosion position is predicted, and further, by calculating the proportional coefficient of corrosion area and corrosion depth, the specific corrosion degree of the steel bar is determined.

[0011] Preferably, step S1 comprises the following steps:

[0012] Step S11: The rectangular waveguide is scanned at different frequencies. fi, ， Transmit microwave signals to the non-corroded reinforced concrete foundation of power transmission and transformation to obtain different frequencies fi The transmission coefficient under S 0 21 ; The transmission coefficient S 0 21 As a benchmark value to characterize whether the steel bars in the foundation are corroded;

[0013] According to the method of step S11, the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the foundation is recorded, and a reference value query unit is constructed; a fitting curve is drawn f ( x 1).

[0014] Preferably, step S2 comprises the following steps:

[0015] Step S21: According to the method of step S1, the rectangular waveguide is scanned at different frequencies. fi, Transmit microwave signals to the reinforced concrete foundation of the power transmission and transformation to be tested, and obtain different frequencies fi The transmission coefficient under S 1 21 ; Establish the mapping relationship between scanning frequency and transmission coefficient, construct the test value query unit, and draw the fitting curve f ( x 2).

[0016] Preferably, step S3 further comprises: calculating the transmission coefficient difference Δ at the same frequency corresponding to the basic measurement position S 21 , preliminarily determine the degree and location of steel bar corrosion, Δ S 21The larger it is, the more serious the corrosion is. The calculation formula is as follows:

[0017] .

[0018] Preferably, the corrosion parameters of the steel bars include the corrosion area and corrosion depth proportionality factor d , where the corrosion area calculation formula is as follows:

[0019] ,

[0020] in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer;

[0021] Δ x is the corrosion length, r is the radius of the steel bar;

[0022] Corrosion depth proportionality factor .

[0023] Preferably, the establishment of the fitting curve includes:

[0024] The horizontal distance is the abscissa and the transmission coefficient is S 0 21 Draw a fitted curve for the ordinate f ( x 1);

[0025] The horizontal distance is the abscissa and the transmission coefficient is S 1 21 Draw a fitted curve for the ordinate f ( x 2) When comparing, first use the transmission coefficient error value Δ S 21 Determine the basic corrosion position, and then call up two sets of fitting curves for comparison according to different basic detection positions, and the specific corrosion degree of the corrosion position can be calculated.

[0026] The invention discloses a power transmission and transformation reinforced concrete foundation corrosion detection system based on microwave transmission method, comprising a microwave signal source, a rectangular waveguide receiving probe, a rectangular waveguide transmitting probe and a host computer, wherein the microwave signal source is used to generate microwave signals with different scanning frequencies, the rectangular waveguide receiving probe and the rectangular waveguide transmitting probe are respectively connected to the signal port of the microwave signal source, the rectangular waveguide transmitting probe sends microwave signals to the tested part of the foundation at a certain scanning frequency, the rectangular waveguide receiving probe receives the transmission signal, and the host computer is connected to the microwave signal source for information exchange.

[0027] Preferably, the host computer includes a reference value query unit, a test value query unit, a data comparison unit and a display unit;

[0028] The reference value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation when it is not corroded;

[0029] The test value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation under the test condition;

[0030] The data comparison unit retrieves the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and draws a fitting curve. f ( x 1) and f ( x 2) Compare the corrosion area and corrosion depth ratio coefficient to calculate the corrosion degree of the foundation;

[0031] The display unit is used for curve f ( x 1) and f ( x 2) results.

[0032] As a preferred embodiment, the corrosion area The calculation formula is as follows:

[0033] ,

[0034] in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer;

[0035] Δ x is the corrosion length, r is the radius of the steel bar;

[0036] Corrosion depth proportionality factor .

[0037] Beneficial effects of the present invention: The reinforced concrete foundation corrosion detection method and system based on the microwave transmission method of the present invention uses microwave signals as signal sources, and preliminarily determines the corrosion situation and foundation corrosion position through the difference between the incident signal and the transmission signal. Furthermore, by comparing the difference between the transmission coefficient of the corroded steel bar and the transmission coefficient of the uncorroded steel bar, the corrosion area and corrosion depth are taken into consideration to comprehensively determine the specific corrosion degree of the steel bar. Compared with the traditional method, the detection efficiency and accuracy are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a simplified flow chart of the method for detecting corrosion of reinforced concrete foundations for power transmission and transformation based on the microwave transmission method.

[0039] Figure 2 It is a schematic diagram of the non-corroded reinforced concrete model of power transmission and transformation of the present invention.

[0040] Figure 3 It is a schematic diagram of the power transmission and transformation reinforced concrete model after local corrosion of the present invention.

[0041] Figure 4 It is a comparison diagram of the transmission coefficient fitting curves before and after the steel bar corrosion of the present invention. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0043] Example:

[0044] like Figure 1 As shown in the figure, a simplified flow chart of the corrosion detection method of reinforced concrete foundation for power transmission and transformation based on microwave transmission method includes the following steps:

[0045] Step S1: The microwave signal source and the rectangular waveguide transmit microwave signals to the uncorroded reinforced concrete foundation of the power transmission and transformation, and determine the scanning frequency of the microwave signal source and the rectangular waveguide. f ,remember: f=(f1, f1,···, fn) , get the corresponding scanning frequency f The transmission coefficient under S 0 21 The baseline value is: S 0 21 =( S 0121 ，S 02 21 ，···，S 0n 21 ); Construct a benchmark value query unit.

[0046] Step S1 includes the following steps:

[0047] Step S11: The rectangular waveguide is scanned at different frequencies. fi, ， Transmit microwave signals to the non-corroded reinforced concrete foundation of power transmission and transformation to obtain different frequencies fi The transmission coefficient under S 0 21 ; The transmission coefficient S 0 21 As a benchmark value to characterize whether the steel bars in the foundation are corroded;

[0048] According to the method of step S11, the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the foundation is recorded, and a reference value query unit is constructed; a fitting curve is drawn f ( x 1).

[0049] Step S2: using a rectangular waveguide to periodically scan the frequency f Scan the reinforced concrete foundation of power transmission and transformation to obtain the transmission coefficient S 1 21 ;remember: S 1 21 =( S 11 21 ，S 12 21 ，···，S 1n 21 );Build a test value query unit.

[0050] Step S2 includes the following steps:

[0051] Step S21: According to the method of step S1, the rectangular waveguide is scanned at different frequencies. fi, Transmit microwave signals to the reinforced concrete foundation of the power transmission and transformation to be tested, and obtain different frequencies fi The transmission coefficient under S 1 21; Establish the mapping relationship between scanning frequency and transmission coefficient, construct the test value query unit, and draw the fitting curve f ( x 2).

[0052] Step S3: By comparing S 0 21 and S 1 21 The size of the value at the corresponding position is used to determine whether the steel bar is corroded; if S 1 21 The value at the corresponding position is less than S 0 21 The value at the corresponding position indicates that the steel bar has been corroded, otherwise it has not been corroded;

[0053] Step S3 also includes: calculating the transmission coefficient difference Δ at the same frequency corresponding to the basic measurement position S 21 , preliminarily determine the degree and location of steel bar corrosion, Δ S 21 The larger it is, the more serious the corrosion is. The calculation formula is as follows:

[0054] .

[0055] Step S4: The data comparison unit retrieves the fitting curves of the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and uses the curves f ( x 1) and f ( x 2) to determine the corrosion parameters of the steel bars.

[0056] The corrosion parameters of steel bars include corrosion area and corrosion depth proportionality factor d ;

[0057] The corrosion area calculation formula is as follows:

[0058] ,

[0059] in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer;

[0060] Δ x is the corrosion length, r is the radius of the steel bar;

[0061] Among them, the corrosion depth proportionality coefficient d The calculation formula is as follows:

[0062] .

[0063] The establishment of the fitting curve includes:

[0064] The horizontal distance is the abscissa and the transmission coefficient is S 0 21 Draw a fitted curve for the ordinate f ( x 1);

[0065] Horizontal distance f is the horizontal axis, with the transmission coefficient S 1 21 Draw a fitted curve for the ordinate f ( x 2) When comparing, first use the transmission coefficient error value Δ S 21 Determine the basic corrosion position, and then call up two sets of fitting curves for comparison according to different basic detection positions, and the specific corrosion degree of the corrosion position can be calculated.

[0066] In this embodiment, a reference value query unit is first constructed, and a microwave incident signal is transmitted to the non-corroded reinforced concrete foundation of the power transmission and transformation through a rectangular waveguide transmitting probe, and a rectangular waveguide receiving probe receives the transmission signal to realize horizontal transmission scanning of the reinforced concrete structure, and obtain S 0 21 The transmission coefficient and S 0 21 The reference value is recorded in the reference value query unit, and the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the foundation is recorded; secondly, a test value query unit is constructed, and the method is the same as above; by checking the deviation of the transmission coefficient, the corrosion location is predicted, and further, by calculating the corrosion area and corrosion depth, the specific corrosion degree of the steel bar is determined.

[0067] The invention discloses a power transmission and transformation reinforced concrete foundation corrosion detection system based on microwave transmission method, comprising a microwave signal source, a rectangular waveguide receiving probe, a rectangular waveguide transmitting probe and a host computer, wherein the microwave signal source is used to generate microwave signals with different scanning frequencies, the rectangular waveguide receiving probe and the rectangular waveguide transmitting probe are respectively connected to the signal port of the microwave signal source, the rectangular waveguide transmitting probe sends microwave signals to the tested part of the foundation at a certain scanning frequency, the rectangular waveguide receiving probe receives the transmission signal, and the host computer is connected to the microwave signal source for information exchange.

[0068] The host computer includes a reference value query unit, a test value query unit, a data comparison unit and a display unit;

[0069] The reference value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation when it is not corroded;

[0070] The test value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation under the test condition;

[0071] The data comparison unit retrieves the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and draws a fitting curve. f ( x 1) and f ( x 2) Compare the corrosion area and corrosion depth ratio coefficient to calculate the corrosion degree of the foundation;

[0072] Display unit for curves f ( x 1) and f ( x 2) results.

[0073] The corrosion area The calculation formula is as follows:

[0074] ,

[0075] in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer;

[0076] Δ x is the corrosion length, r is the radius of the steel bar;

[0077] Among them, the corrosion depth proportionality coefficient d The calculation formula is as follows:

[0078] .

[0079] A specific embodiment is as follows:

[0080] The scaled model of the reinforced concrete foundation of power transmission and transformation without corrosion and after corrosion is taken as an example for analysis. The scaled model of the reinforced concrete foundation of power transmission and transformation is established using CST software. The length, width and height of the concrete foundation are 900, 200 and 250 mm respectively; the diameter and length of the steel bar are 22 mm and 900 mm respectively; the depth and length of the corrosion layer are 5.5 mm and 100 mm respectively; according to the International Electrotechnical Commission standard, WR-340 is selected as the rectangular waveguide for scanning, and its size information is shown in Table 1.

[0081] Table 1. EIA-International Standard WR-340 Parameters and Dimensions

[0082]

[0083] like Figure 2 and Figure 3 As shown in the figure, two sets of simulation models are established according to the structural dimensions and material properties of concrete, steel bars, rectangular waveguides, etc. The rectangular waveguide is located at the center of the front (where the steel bars are located) and is 3 mm away from the surface of the model. Since the main component of rust is iron oxide, the corrosion layer material is set according to its properties such as conductivity and dielectric constant. Details such as the scanning direction and scanning range of the rectangular waveguide are marked in the figure.

[0084] After the microwave signal source generates a microwave signal, the waveguide is used to perform transmission scanning on the reinforced concrete surface. The rectangular waveguide ① on the front side transmits the microwave signal, and the rectangular waveguide ② on the rear side receives the transmission signal carrying corrosion information (such as Figure 2 As shown in (b), horizontal direction), the scanning step length is 5mm, that is, scanning is performed every 5mm.

[0085] The transmission coefficient results before and after local corrosion of steel bars are as follows Figure 4 As shown, the black solid line and the black dotted line are respectively uncorroded and partially corroded. S 21 Result curve. Figure 4 It can be seen that the two curves have no difference far away from the corrosion position, and the corrosion degree is distinguished in the range of -90~90mm. The closer to the center, the more local corrosion S 21 The smaller the amplitude is, the smaller the amplitude is. Due to the scattering characteristics of microwaves, the corrosion degree range is larger than the local corrosion range. At the center of the steel bar, that is, the center of the corrosion layer, the corroded steel bar S 21 The amplitude reached the minimum (-17.58 dB), and the difference with the uncorroded amplitude at the same position reached the maximum (1.53 dB), which verified the feasibility of microwave transmission method to detect the corrosion of reinforced concrete in power transmission and transformation. S 21 The minimum amplitude corresponding scale can locate the corrosion position.

[0086] The specific implementation manner described above is a preferred implementation manner of the reinforced concrete foundation corrosion detection method and system based on the microwave transmission method of the present invention, and is not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to this specific implementation manner. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A reinforced concrete foundation corrosion detection method based on microwave transmission method, characterized in that: The steps include: Step S1: The microwave signal source and the rectangular waveguide transmit microwave signals to the uncorroded reinforced concrete foundation of the power transmission and transformation, and determine the scanning frequency of the microwave signal source and the rectangular waveguide. f ,remember: f=(f1, f1,···, fn) , get the corresponding scanning frequency f The transmission coefficient under S 0 21 The baseline value is: S 0 21 =( S 01 21 ，S 02 21 ，···，S 0n 21 );Construct a benchmark value query unit; Step S2: using a rectangular waveguide to periodically scan the frequency f Scan the reinforced concrete foundation of power transmission and transformation to obtain the transmission coefficient S 1 21 ;remember: S 1 21 =( S 11 21 ，S 12 21 ，···，S 1n 21 );Build a test value query unit; Step S3: By comparing S 0 21 and S 1 21 The size of the value at the corresponding position is used to determine whether the steel bar is corroded; if S 1 21 The value at the corresponding position is less than S 0 21 The value at the corresponding position indicates that the steel bar has been corroded, otherwise it has not been corroded; Step S4: The data comparison unit retrieves the fitting curves of the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and uses the curves f ( x 1) and f ( x 2) Compare and determine the corrosion parameters of the steel bars; Step S1 includes the following steps: Step S11: The rectangular waveguide is scanned at different frequencies. fi , , transmit microwave signals to the non-corroded reinforced concrete foundation of power transmission and transformation, and obtain different frequencies fi The transmission coefficient under S 0 21 ; The transmission coefficient S 0 21 As a benchmark value to characterize whether the steel bars in the foundation are corroded; According to the method of step S11, the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the foundation is recorded, and a reference value query unit is constructed; a fitting curve is drawn f ( x 1); Calculate the error value of the transmission coefficient, determine the basic corrosion position, and adjust the fitting curve according to different detection positions. f ( x 1) and f ( x 2) analyzing and calculating the corrosion parameters to determine the specific corrosion degree of the corrosion location; By calculating the transmission coefficient difference Δ at the same frequency corresponding to the basic measurement position S 21 , preliminarily determine the degree of steel bar corrosion, Δ S 21 The larger it is, the more serious the corrosion is. The calculation formula is as follows: ； The corrosion parameters of steel bars include corrosion area and corrosion depth proportionality factor d , where the corrosion area calculation formula is as follows: ， in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer; Δ x is the corrosion length, r is the radius of the steel bar; Corrosion depth proportionality factor ; Step S2 includes the following steps: Step S21: According to the method of step S1, the rectangular waveguide is scanned at different frequencies. fi, , transmit microwave signals to the reinforced concrete foundation of the power transmission and transformation to be tested, and obtain different frequencies fi The transmission coefficient under S 1 21 ; Establish the mapping relationship between scanning frequency and transmission coefficient, construct the test value query unit, and draw the fitting curve f ( x 2); The establishment of the fitting curve includes: The horizontal distance is the abscissa and the transmission coefficient is S 0 21 Draw a fitted curve for the ordinate f ( x 1); The horizontal distance is the abscissa and the transmission coefficient is S 1 21 Draw a fitted curve for the ordinate f ( x 2).

2. A reinforced concrete foundation corrosion detection system based on microwave transmission method, characterized by: It includes a microwave signal source, a rectangular waveguide receiving probe, a rectangular waveguide transmitting probe and a host computer. The microwave signal source is used to generate microwave signals with different scanning frequencies. The rectangular waveguide receiving probe and the rectangular waveguide transmitting probe are respectively connected to the signal port of the microwave signal source. The rectangular waveguide transmitting probe sends microwave signals to the basic tested part at a certain scanning frequency. The rectangular waveguide receiving probe receives the transmission signal. The host computer is connected to the microwave signal source to exchange information. The host computer includes a reference value query unit, a test value query unit, a data comparison unit and a display unit; The reference value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation when it is not corroded; The test value query unit stores the mapping relationship between the scanning frequency and the transmission coefficient of different parts of the power transmission and transformation reinforced concrete foundation under test; The data comparison unit retrieves the mapping relationship between the scanning frequency and the transmission coefficient corresponding to the same basic part in the reference value query unit and the test value query unit respectively, and draws a fitting curve. f ( x 1) and f ( x 2) Compare the corrosion area and corrosion depth ratio coefficient to calculate the corrosion degree of the foundation; The display unit is used for curve f ( x 1) and f ( x 2) Results; The corrosion area The calculation formula is as follows: ， in: , a is the starting position of the corrosion zone, b is the end position of the corrosion zone, c is the edge position of the corrosion layer; Δ x is the corrosion length, r is the radius of the steel bar; Corrosion depth proportionality factor .

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