Method for detecting internal corrosion and water accumulation of a column, detection terminal and detection system

Abstract

The application discloses a kind of column internal corrosion and water detection method, detection terminal and detection system, comprising: obtaining the ultrasonic echo signal reflected by target column;The ultrasonic echo signal is filtered to obtain target signal;Energy analysis is carried out on target signal, to determine whether target column has corrosion and waterlogging.When steel structure column internal corrosion and waterlogging occur, the energy characteristics of ultrasonic echo signal will change.The application uses ultrasonic wave to detect, extracts the energy characteristics of ultrasonic echo signal, determines the corrosion and waterlogging of column according to energy characteristics, can detect the corrosion and waterlogging inside column, and the detection result is accurate.The detection terminal has wide application range, can not only be used for corrosion detection, water detection of railway station building steel structure column inner wall, but also can be used for wall thickness, internal foreign matter detection of pipe component (including metal and non-metal pipe), with fast detection speed, high precision and more intelligence.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and more specifically to a method, detection terminal and detection system for detecting internal corrosion of columns. Background Technology

[0002] Currently, steel structural columns are an important part of high-speed railway station buildings and canopies. However, these columns are susceptible to corrosion due to external environmental factors, which can affect the lifespan of the steel structure.

[0003] However, in existing technologies, the steel structure columns are usually inspected by staff to check for corrosion. But because the steel structure columns are hollow and fixed to the ground at the bottom, it is impossible to know whether there is corrosion inside the steel structure columns, which seriously threatens the safety of the station building.

[0004] Therefore, the inaccuracy of manual inspection of steel structure columns in existing technologies, which poses safety risks, is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a method, detection terminal, and detection system for detecting internal corrosion and water accumulation in columns. The method includes: acquiring the ultrasonic echo signal reflected by the target column; filtering the ultrasonic echo signal to obtain the target signal; and performing energy analysis on the target signal to determine whether the target column has experienced corrosion and water accumulation. When internal corrosion occurs in a steel structure column, the energy characteristics of the ultrasonic echo signal will change. This embodiment of the invention uses ultrasonic waves for detection, extracts the energy characteristics from the ultrasonic echo signal, and determines the corrosion and water accumulation status of the column based on these energy characteristics. This method can detect internal corrosion and water accumulation in columns with accurate results.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for detecting internal corrosion and water accumulation in a column includes the following steps:

[0008] Acquire the ultrasonic echo signal reflected by the target column;

[0009] The ultrasonic echo signal is filtered to obtain the target signal;

[0010] Energy analysis is performed on the target signal to determine whether the target column is corroded.

[0011] Preferably, the ultrasonic echo signals are multiple; the step of filtering the ultrasonic echo signals to obtain the target signal includes:

[0012] Each ultrasonic echo signal was subjected to a Fourier transform to obtain multiple frequency domain signals;

[0013] Determine the dominant frequency of each frequency domain signal;

[0014] If there exists a frequency domain signal whose difference between the main frequency and the preset frequency is within a preset range, then the ultrasonic echo signal corresponding to that frequency domain signal is taken as the target signal.

[0015] Preferably, the step of performing energy analysis on the target signal to determine whether the target column is corroded and has water accumulation includes:

[0016] Power spectrum analysis is performed on the target signal to obtain the target power spectrum;

[0017] Determine the maximum power value in the target power spectrum, and determine the difference between the maximum power value and the preset power value, denoted as the first difference;

[0018] If the first difference is less than the first preset difference and greater than the second preset difference, then it is determined that the target column does not have rust or water accumulation.

[0019] If the first difference is not less than the first preset difference, then the target column is determined to be corroded and waterlogged.

[0020] If the first difference is not greater than the second preset difference, then the target column is determined to be rusted and waterlogged;

[0021] Wherein, the first preset difference is positive, and the second preset difference is negative.

[0022] Preferably, before acquiring the ultrasonic echo signal reflected by the target column, the detection method further includes:

[0023] An ultrasonic signal is sent to the target column; wherein the preset frequency is the same as the frequency of the ultrasonic signal.

[0024] Preferably, the step of filtering the ultrasonic echo signal to obtain the target signal includes:

[0025] The target signal is obtained by filtering the ultrasonic echo signal using wavelet transform.

[0026] Preferably, the step of filtering the ultrasonic echo signal using wavelet transform to obtain the target signal includes:

[0027] Wavelet transform is performed on the ultrasonic echo signal to obtain the components in the frequency domain;

[0028] The target signal is obtained by selecting components within a preset frequency range.

[0029] Preferably, the step of performing energy analysis on the target signal to determine whether the target column is corroded includes:

[0030] The target signal is subjected to time-frequency analysis to obtain the wavelet coefficients corresponding to each frequency.

[0031] Determine the largest wavelet coefficient among all wavelet coefficients, and determine the difference between the largest wavelet coefficient and the preset coefficient, denoted as the second difference;

[0032] If the second difference is less than the third preset difference and greater than the fourth preset difference, then it is determined that the target column does not have rust or water accumulation.

[0033] If the second difference is not less than the third preset difference, then the target column is determined to be corroded and waterlogged.

[0034] If the second difference is not greater than the fourth preset difference, then the target column is determined to be rusted and waterlogged.

[0035] The third preset difference value is positive, and the fourth preset difference value is negative.

[0036] A terminal for detecting internal corrosion and water accumulation in a column includes a processor and a memory. The memory stores a computer program, and the processor calls and runs the computer program stored in the memory to perform a method for detecting internal corrosion and water accumulation in the column.

[0037] A system for detecting internal corrosion and water accumulation in columns includes: an ultrasonic transmitter, an ultrasonic receiver, and a detection terminal;

[0038] The ultrasonic transmitter is used to transmit ultrasonic signals toward the target column.

[0039] The ultrasonic receiver is used to acquire the ultrasonic echo signal reflected by the target column and send the ultrasonic echo signal reflected by the target column to the detection terminal.

[0040] Preferably, the ultrasonic transmitter includes: an ultrasonic probe and a water film layer; the water film layer is disposed at the front end of the ultrasonic probe.

[0041] As can be seen from the above technical solution, compared with the prior art, this invention discloses a method, detection terminal, and detection system for detecting internal corrosion and water accumulation in columns. The method includes: acquiring the ultrasonic echo signal reflected by the target column; filtering the ultrasonic echo signal to obtain the target signal; and performing energy analysis on the target signal to determine whether the target column has corrosion and water accumulation. When internal corrosion occurs in a steel structure column, the energy characteristics of the ultrasonic echo signal will change. This embodiment of the invention uses ultrasonic waves for detection, extracts the energy characteristics from the ultrasonic echo signal, and determines the corrosion and water accumulation status of the column based on the energy characteristics. This method can accurately detect internal corrosion and water accumulation in columns. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0043] Figure 1 A schematic diagram illustrating the implementation process of a method for detecting internal corrosion and water accumulation in a column, provided in an embodiment of the present invention.

[0044] Figure 2 The waveform diagram of the ultrasonic signal provided in the embodiment of the present invention.

[0045] Figure 3 The spectrum diagram of the target signal provided in the embodiments of the present invention.

[0046] Figure 4 The power spectrum comparison diagram of the target signal under the conditions of normal column, rust and water accumulation, and corrosion and water accumulation is provided for the embodiments of the present invention.

[0047] Figure 5 This is a schematic diagram of the internal corrosion and water accumulation detection device for columns provided in an embodiment of the present invention.

[0048] Figure 6 This is a schematic diagram of a detection terminal provided in an embodiment of the present invention.

[0049] Figure 7 This is a schematic diagram of a steel column structure provided in an embodiment of the present invention.

[0050] Figure 8 This is a schematic diagram of the initial ultrasonic signal provided in an embodiment of the present invention.

[0051] Figure 9 This is a schematic diagram of the filtered signal provided in an embodiment of the present invention.

[0052] Figure 10 This is a schematic diagram of the power spectrum provided in an embodiment of the present invention.

[0053] Figure 11 This is a schematic diagram of time-frequency analysis of the presence or absence of water accumulation provided in an embodiment of the present invention. Detailed Implementation

[0054] 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, and 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.

[0055] This invention discloses a method for detecting internal corrosion and water accumulation in columns, comprising the following steps:

[0056] Acquire the ultrasonic echo signal reflected by the target column;

[0057] The ultrasonic echo signal is filtered to obtain the target signal;

[0058] Energy analysis is performed on the target signal to determine whether the target column is corroded or has water accumulation.

[0059] To further optimize the above technical solution, multiple ultrasonic echo signals are used; the filtering of the ultrasonic echo signals to obtain the target signal includes:

[0060] Each ultrasonic echo signal was subjected to a Fourier transform to obtain multiple frequency domain signals;

[0061] Determine the dominant frequency of each frequency domain signal;

[0062] If there exists a frequency domain signal whose difference between the main frequency and the preset frequency is within a preset range, then the ultrasonic echo signal corresponding to that frequency domain signal is taken as the target signal.

[0063] To further optimize the above technical solution, energy analysis is performed on the target signal to determine whether the target column is corroded or has water accumulation, including:

[0064] Power spectrum analysis is performed on the target signal to obtain the target power spectrum;

[0065] Determine the maximum power value in the target power spectrum, and determine the difference between the maximum power value and the preset power value, denoted as the first difference;

[0066] If the first difference is less than the first preset difference and greater than the second preset difference, then it is determined that the target column does not have rust or water accumulation.

[0067] If the first difference is not less than the first preset difference, then the target column is determined to be corroded and waterlogged.

[0068] If the first difference is not greater than the second preset difference, then the target column is determined to be rusted and waterlogged;

[0069] Wherein, the first preset difference is positive, and the second preset difference is negative.

[0070] To further optimize the above technical solution, before acquiring the ultrasonic echo signal reflected by the target column, the detection method further includes:

[0071] An ultrasonic signal is sent to the target column; wherein the preset frequency is the same as the frequency of the ultrasonic signal.

[0072] To further optimize the above technical solution, the ultrasonic echo signal is filtered to obtain the target signal, including:

[0073] The target signal is obtained by filtering the ultrasonic echo signal using wavelet transform.

[0074] To further optimize the above technical solution, wavelet transform is used to filter the ultrasonic echo signal to obtain the target signal, including:

[0075] Wavelet transform is performed on the ultrasonic echo signal to obtain the components in the frequency domain;

[0076] The target signal is obtained by selecting components within a preset frequency range.

[0077] To further optimize the above technical solution, energy analysis is performed on the target signal to determine whether the target column is corroded or has water accumulation, including:

[0078] The target signal is subjected to time-frequency analysis to obtain the wavelet coefficients corresponding to each frequency.

[0079] Determine the largest wavelet coefficient among all wavelet coefficients, and determine the difference between the largest wavelet coefficient and the preset coefficient, denoted as the second difference;

[0080] If the second difference is less than the third preset difference and greater than the fourth preset difference, then it is determined that the target column does not have rust or water accumulation.

[0081] If the second difference is not less than the third preset difference, then the target column is determined to be corroded and waterlogged.

[0082] If the second difference is not greater than the fourth preset difference, then the target column is determined to be rusted and waterlogged.

[0083] The third preset difference value is positive, and the fourth preset difference value is negative.

[0084] A terminal for detecting internal corrosion and water accumulation in a column includes a processor and a memory. The memory stores a computer program, and the processor calls and runs the computer program stored in the memory to perform a method for detecting internal corrosion and water accumulation in the column.

[0085] A system for detecting internal corrosion and water accumulation in columns includes: an ultrasonic transmitter, an ultrasonic receiver, and a detection terminal;

[0086] The ultrasonic transmitter is used to transmit ultrasonic signals toward the target column.

[0087] The ultrasonic receiver is used to acquire the ultrasonic echo signal reflected by the target column and send the ultrasonic echo signal reflected by the target column to the detection terminal.

[0088] To further optimize the above technical solution, the ultrasonic transmitter includes: an ultrasonic probe and a water film layer; the water film layer is disposed at the front end of the ultrasonic probe.

[0089] See Figure 1 The diagram illustrates a flowchart of a method for detecting internal corrosion and water accumulation in a column according to an embodiment of the present invention, which is described in detail below:

[0090] S101: Acquire the ultrasonic echo signal reflected by the target column;

[0091] S102: Filter the ultrasonic echo signal to obtain the target signal;

[0092] S103: Perform energy analysis on the target signal to determine whether the target column is corroded or has water accumulation.

[0093] In this embodiment of the invention, research has shown that the energy characteristics of the ultrasonic echo signal change when the target column exhibits corrosion and water accumulation. Based on this, this embodiment employs an ultrasonic transmitter to emit ultrasonic signals towards the target column for detection, acquiring the ultrasonic echo signal and extracting its energy characteristics. The corrosion status of the target column is determined based on these energy characteristics, enabling the detection of internal corrosion and water accumulation. The detection results are accurate, allowing for timely detection of column corrosion and water accumulation, and enabling appropriate measures to prevent accidents. Furthermore, no personnel inspection is required, saving significant manpower and resources.

[0094] In one possible implementation, there are multiple ultrasonic echo signals; S102 may include:

[0095] S1021: Perform Fourier transform on each ultrasonic echo signal to obtain multiple frequency domain signals;

[0096] S1022: Determine the dominant frequency of each frequency domain signal;

[0097] S1023: If there is a frequency domain signal whose difference between the main frequency and the preset frequency is within the preset range, then the ultrasonic echo signal corresponding to the frequency domain signal shall be used as the target signal.

[0098] Typically, the ultrasonic echo signal received by an ultrasonic receiver is not a pure echo signal reflected from the target column; it contains a lot of noise. In this embodiment of the invention, a Fourier transform is performed on the received signal to determine the dominant frequency of each ultrasonic echo signal. The signal whose dominant frequency is close to the frequency of the ultrasonic signal emitted by the ultrasonic transmitter is the true ultrasonic echo signal reflected from the target column, and this signal is extracted as the target signal. For example, Figure 2 The waveform of the ultrasonic signal emitted by the ultrasonic transmitter is shown. Figure 3 The spectrum obtained by the Fourier transform of the target signal is shown. The dominant frequency of the target signal is the same as the frequency of the ultrasonic signal.

[0099] The preset frequency is the frequency of the ultrasonic signal emitted by the ultrasonic transmitter.

[0100] For example, the preset frequency is 5 MHz. Since the ultrasonic transmitter probe has a certain diameter, there will be an error of approximately ±0.5 MHz. Therefore, this embodiment of the invention sets a threshold range; any deviation between the signal's main frequency and the preset frequency within the preset range can be considered a target signal, thus improving detection accuracy.

[0101] In one possible implementation, S103 may include:

[0102] S1031: Perform power spectrum analysis on the target signal to obtain the target power spectrum;

[0103] S1032: Determine the maximum power value in the target power spectrum, and determine the difference between the maximum power value and the preset power value, denoted as the first difference;

[0104] S1033: If the first difference is less than the first preset difference and greater than the second preset difference, then it is determined that the target column is free of rust.

[0105] S1034: If the first difference is not less than the first preset difference, then the target column is determined to be corroded and waterlogged;

[0106] S1035: If the first difference is not greater than the second preset difference, then the target column is determined to be rusted and waterlogged; wherein, the first preset difference is positive and the second preset difference is negative.

[0107] In this embodiment of the invention, power spectrum analysis can be used to extract the energy characteristics of ultrasonic echo signals. Experiments have shown that power spectrum analysis of sample columns (normal columns, rusted water-filled columns, and corroded water-filled columns) reveals that the maximum power value in the power spectrum of the ultrasonic echo signal of rusted columns is lower than that of normal columns; while the maximum power value in the power spectrum of the ultrasonic echo signal of corroded columns is higher than that of normal columns. For example, referencing... Figure 4 .

[0108] Based on this, the present invention performs power spectrum analysis on the target signal obtained after filtering. If the maximum power value in the power spectrum is too large, it indicates that the target column is corroded; if the maximum power value is too small, it indicates that the target column is rusted and has water accumulation; if the maximum power value is neither too large nor too small, it indicates that the target column is normal and has no corrosion.

[0109] The preset power value is the maximum power value in the power spectrum of the ultrasonic echo signal of a normal column. Furthermore, the preset power value varies depending on the column material; the preset power value should be set according to the material of the target column.

[0110] In this embodiment of the invention, to improve the accuracy of detection, a certain margin is set. When the first difference is within a certain range (from the second preset difference to the first preset difference), it is considered normal. The first preset difference and the second preset difference can be set according to actual application requirements. For example, the first preset difference is 0.2, and the second preset difference is -0.2.

[0111] In one possible implementation, prior to S101, the detection method may further include:

[0112] S104: Send an ultrasonic signal to the target column;

[0113] The preset frequency is the same as the frequency of the ultrasonic signal.

[0114] In one possible implementation, S102 may include:

[0115] S1024: Wavelet transform is used to filter the ultrasonic echo signal to obtain the target signal.

[0116] In one possible implementation, S1021 may include:

[0117] 1. Perform wavelet transform on the ultrasonic echo signal to obtain the components in the frequency domain;

[0118] 2. Select components within a preset frequency range to obtain the target signal.

[0119] In this embodiment of the invention, wavelet transform can be used for filtering to extract components within a preset frequency range. The center frequency of the preset frequency range is the frequency of the ultrasonic signal emitted by the ultrasonic transmitter, used to remove noise and extract the useful signal. The preset frequency range can be set according to actual application requirements.

[0120] In one possible implementation, S103 includes:

[0121] S1036: Perform time-frequency analysis on the target signal to obtain the wavelet coefficients corresponding to each frequency;

[0122] S1037: Determine the largest wavelet coefficient among all wavelet coefficients, and determine the difference between the largest wavelet coefficient and the preset coefficient, denoted as the second difference;

[0123] S1038: If the second difference is less than the third preset difference and greater than the fourth preset difference, then it is determined that the target column does not have rust or water accumulation;

[0124] S1039: If the second difference is not less than the third preset difference, then the target column is determined to be corroded and waterlogged;

[0125] S10310: If the second difference is not greater than the fourth preset difference, then the target column is determined to be rusted and waterlogged;

[0126] The third preset difference is positive, and the fourth preset difference is negative.

[0127] Since S1021 performs wavelet decomposition on the ultrasonic echo signal, the components of multiple wavelet decompositions within a preset frequency range form the target signal. This embodiment of the invention can directly perform time-frequency analysis on the target signal obtained from wavelet decomposition to obtain the maximum wavelet coefficient. The wavelet coefficient represents the energy distribution. Experiments have shown that the maximum wavelet coefficient of rusted and water-filled columns is smaller than that of normal columns; while the maximum wavelet coefficient of corroded and water-filled columns is larger than that of normal columns.

[0128] Based on this, embodiments of the present invention calculate the maximum wavelet coefficient of the target column and compare it with the maximum wavelet coefficient of a normal column (i.e., the preset coefficient) to determine whether the target column is corroded or has water accumulation.

[0129] The preset coefficients differ for columns made of different materials, and should be set according to the material of the target column.

[0130] Similarly, to improve the accuracy of the detection, a certain margin is set for the second difference. When the second difference is within a certain range (from the fourth preset difference to the third preset difference), it is considered normal. The third and fourth preset differences can be set according to actual application requirements.

[0131] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0132] The following are device embodiments of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0133] Figure 5 A schematic diagram of the internal corrosion detection device for columns provided in an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0134] The device includes:

[0135] The echo signal acquisition module 21 is used to acquire the ultrasonic echo signal reflected by the target column;

[0136] Signal extraction module 22 is used to filter the ultrasonic echo signal to obtain the target signal;

[0137] The results analysis module 23 is used to perform energy analysis on the target signal to determine whether the target column is corroded.

[0138] In one possible implementation, there are multiple ultrasonic echo signals; the signal extraction module 22 may include:

[0139] Fourier transform unit 221 is used to perform Fourier transform on each ultrasonic echo signal to obtain multiple frequency domain signals.

[0140] The main frequency determination unit 222 is used to determine the main frequency of each frequency domain signal;

[0141] The first signal extraction unit 223 is used to take the ultrasonic echo signal corresponding to the frequency domain signal as the target signal if there is a frequency domain signal whose difference between the main frequency and the preset frequency is within a preset range.

[0142] In one possible implementation, the result analysis module 23 may include:

[0143] The power spectrum analysis unit 231 is used to perform power spectrum analysis on the target signal to obtain the target power spectrum;

[0144] The power difference determination unit 232 is used to determine the maximum power value in the target power spectrum and to determine the difference between the maximum power value and the preset power value, which is denoted as the first difference.

[0145] The first judgment unit 233 is used to determine that the target column does not have rust or water accumulation if the first difference is less than the first preset difference and greater than the second preset difference.

[0146] The second judgment unit 234 is used to determine the target column corrosion and water accumulation if the first difference is not less than the first preset difference.

[0147] The third judgment unit 235 is used to determine whether the target column is rusted and has water accumulation if the first difference is not greater than the second preset difference.

[0148] The first preset difference is positive, and the second preset difference is negative.

[0149] In one possible implementation, the detection device may further include:

[0150] Signal transmitting module 24 is used to transmit ultrasonic signals to the target column;

[0151] The preset frequency is the same as the frequency of the ultrasonic signal.

[0152] In one possible implementation, the signal extraction module 22 may include:

[0153] The second signal extraction unit 224 is used to filter the ultrasonic echo signal using wavelet transform to obtain the target signal.

[0154] In one possible implementation, the second signal extraction unit 224 may be specifically used for:

[0155] Wavelet transform is performed on the ultrasonic echo signal to obtain the components in the frequency domain;

[0156] The target signal is obtained by selecting components within a preset frequency range.

[0157] In one possible implementation, the result analysis module 23 may include:

[0158] The time-frequency analysis unit 236 is used to perform time-frequency analysis on the target signal and obtain the wavelet coefficients corresponding to each frequency.

[0159] The coefficient difference determination unit 237 is used to determine the largest wavelet coefficient among all wavelet coefficients and to determine the difference between the largest wavelet coefficient and the preset coefficient, which is denoted as the second difference.

[0160] The fourth judgment unit 238 is used to determine that the target column does not have rust or water accumulation if the second difference is less than the third preset difference and greater than the fourth preset difference.

[0161] The fifth judgment unit 239 is used to determine the corrosion and water accumulation of the target column if the second difference is not less than the third preset difference.

[0162] The sixth judgment unit 2310 is used to determine whether the target column is rusted and has water accumulation if the second difference is not greater than the fourth preset difference.

[0163] The third preset difference is positive, and the fourth preset difference is negative.

[0164] Figure 6 This is a schematic diagram of the detection terminal 3 provided in an embodiment of the present invention. Figure 6 As shown, the detection terminal 3 in this embodiment includes a processor 30 and a memory 31. The memory 31 is used to store a computer program 32, and the processor 30 is used to call and run the computer program 32 stored in the memory 31 to execute the steps in the above embodiments of the column internal corrosion detection methods, for example... Figure 1 The steps S101 to S103 are shown. Alternatively, the processor 30 is used to call and run the computer program 32 stored in the memory 31 to implement the functions of each module / unit in the above-described device embodiments, for example... Figure 5 The functions of modules 21 to 23 are shown.

[0165] For example, computer program 32 can be divided into one or more modules / units, one or more of which are stored in memory 31 and executed by processor 30 to complete the present invention. One or more modules / units can be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of computer program 32 in detection terminal 3. For example, computer program 32 can be divided into... Figure 5 Modules / units 21 to 23 are shown.

[0166] The testing terminal 3 can be a desktop computer, laptop, handheld computer, or cloud server, etc. The testing terminal 3 may include, but is not limited to, a processor 30 and a memory 31. Those skilled in the art will understand that... Figure 6 This is merely an example of the detection terminal 3 and does not constitute a limitation on the detection terminal 3. It may include more or fewer components than shown, or combine certain components, or different components. For example, the terminal may also include input / output devices, network access devices, buses, etc.

[0167] The processor 30 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0168] The memory 31 can be an internal storage unit of the detection terminal 3, such as a hard disk or memory of the detection terminal 3. The memory 31 can also be an external storage device of the detection terminal 3, such as a plug-in hard disk, SmartMedia Card (SMC), Secure Digital (SD) card, or Flash Card equipped on the detection terminal 3. Furthermore, the memory 31 can include both internal storage units and external storage devices of the detection terminal 3. The memory 31 is used to store computer programs and other programs and data required by the terminal. The memory 31 can also be used to temporarily store data that has been output or will be output.

[0169] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0170] This invention also provides a column internal corrosion detection system, including: an ultrasonic transmitter, an ultrasonic receiver, and a detection terminal as described in the above embodiments;

[0171] The ultrasonic transmitter is used to send ultrasonic signals toward the target column;

[0172] The ultrasonic receiver is used to acquire the ultrasonic echo signal reflected by the target column and send the ultrasonic echo signal reflected by the target column to the detection terminal.

[0173] In one possible implementation, the ultrasonic transmitter may include: an ultrasonic probe and a water film layer;

[0174] The water film layer is placed at the front end of the ultrasonic probe.

[0175] In this embodiment of the invention, a water film layer can be set at the front end of the ultrasonic probe and used as a coupling agent. At the same time, the flexibility of the water film layer is utilized to ensure full contact between the target column surface and the ultrasonic probe, thereby improving the stability of coupling and the effectiveness and accuracy of detection.

[0176] The ultrasonic energy reflection calculation method involved in this invention is specifically embodied in the following embodiments:

[0177] Taking the YPZ2 type steel structure column used on the canopy of railway station buildings as an example, such as Figure 7 As shown. The heterogeneous interfaces for ultrasonic wave propagation are the steel-air interface and the steel-water interface. Since the water accumulation area is significantly larger than the steel column wall thickness, the ultrasonic waves attenuate after propagating in the water, and there is no echo signal. The governing equation for ultrasonic wave propagation at the heterogeneous interface is shown in equation (1).

[0178]

[0179] In the formula, u x It is displacement, c L It is the longitudinal wave velocity of ultrasound. Given the displacement value u... x The proportion of reflected energy is derived as shown in equation (2).

[0180]

[0181] In the formula, B = Z2 / Z1, where Z1 and Z2 are the acoustic impedances of the materials, respectively. When ultrasonic waves propagate through heterogeneous interfaces without considering attenuation, the proportion of reflected ultrasonic energy depends on the materials of the heterogeneous interfaces. Two types of heterogeneous interfaces are selected: steel-air and steel-water, as shown in Table 1. Table 1 shows that the reflected energy of ultrasonic waves at the steel-water interface is reduced by 12.5% ​​compared to the steel-air interface. Therefore, the change in ultrasonic energy can effectively determine the water accumulation situation in the steel structure columns.

[0182] Table 1. Parameters and energy percentage of the material interface

[0183]

[0184] The power spectrum analysis algorithm involved in this invention is specifically implemented as follows:

[0185] The mathematical method used in power spectrum analysis is Fourier transform, which represents the change of signal power with frequency within a unit frequency band. The following is the principle of power spectrum plotting.

[0186] Let X m If (m = 0, 1, 2, ..., N-1) is a time series data sampled at N equal time intervals, then its mean square value (average power) is:

[0187]

[0188] The power spectrum is obtained by decomposing equation (3) into components of each frequency to understand the proportion of each frequency component in the overall average power.

[0189] The wavelet transform time-frequency analysis algorithm involved in this invention is specifically embodied as follows:

[0190] Wavelet transform utilizes a wavelet basis that can adaptively adjust scaling and translation, and selects an appropriate time and frequency resolution to analyze signals. This patent employs continuous wavelet transform to analyze ultrasonic reflection signals.

[0191] In general, the signal f(t)∈L 2 The continuous wavelet transform of (R) can be defined as:

[0192]

[0193] In the formula, a is the scaling factor; b is the translation factor; ψ a,b (t) is a wavelet basis; <f(t),ψ a,b (t)> represents the wavelet coefficients. There are many choices for wavelet functions. Compared with other wavelet bases, Cmor has higher time-frequency clustering, so Cmor is used as the wavelet base.

[0194] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0195] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for detecting internal corrosion and water accumulation in a column, characterized in that, Includes the following steps: Acquire the ultrasonic echo signal reflected by the target column; The ultrasonic echo signal is filtered to obtain the target signal; Energy analysis is performed on the target signal to determine whether the target column is corroded or has water accumulation; specifically, this includes performing power spectrum analysis on the target signal to obtain the target power spectrum. Determine the maximum power value in the target power spectrum, and determine the difference between the maximum power value and the preset power value, denoted as the first difference; If the first difference is less than the first preset difference and greater than the second preset difference, then it is determined that the target column does not have rust or water accumulation. If the first difference is not less than the first preset difference, then the target column is determined to be corroded and waterlogged. If the first difference is not greater than the second preset difference, then the target column is determined to be rusted and waterlogged; Wherein, the first preset difference is positive, and the second preset difference is negative; or: The target signal is subjected to time-frequency analysis to obtain the wavelet coefficients corresponding to each frequency. Determine the largest wavelet coefficient among all wavelet coefficients, and determine the difference between the largest wavelet coefficient and the preset coefficient, denoted as the second difference; If the second difference is less than the third preset difference and greater than the fourth preset difference, then it is determined that the target column does not have rust or water accumulation. If the second difference is not less than the third preset difference, then the target column is determined to be corroded and waterlogged. If the second difference is not greater than the fourth preset difference, then the target column is determined to be rusted and waterlogged. The third preset difference value is positive, and the fourth preset difference value is negative.

2. The method for detecting internal corrosion and water accumulation in a column according to claim 1, characterized in that, The ultrasonic echo signals are multiple; the filtering of the ultrasonic echo signals to obtain the target signal includes: Each ultrasonic echo signal was subjected to a Fourier transform to obtain multiple frequency domain signals; Determine the dominant frequency of each frequency domain signal; If there exists a frequency domain signal whose difference between the main frequency and the preset frequency is within a preset range, then the ultrasonic echo signal corresponding to that frequency domain signal is taken as the target signal.

3. A method for detecting internal corrosion and water accumulation in a column according to claim 1 or 2, characterized in that, Before acquiring the ultrasonic echo signal reflected by the target column, the detection method further includes: An ultrasonic signal is sent to the target column; wherein the preset frequency is the same as the frequency of the ultrasonic signal.

4. The method for detecting internal corrosion and water accumulation in a column according to claim 1, characterized in that, The step of filtering the ultrasonic echo signal to obtain the target signal includes: The target signal is obtained by filtering the ultrasonic echo signal using wavelet transform.

5. The method for detecting internal corrosion and water accumulation in a column according to claim 4, characterized in that, The step of filtering the ultrasonic echo signal using wavelet transform to obtain the target signal includes: Wavelet transform is performed on the ultrasonic echo signal to obtain the components in the frequency domain; The target signal is obtained by selecting components within a preset frequency range.

6. A terminal for detecting internal corrosion and water accumulation in a column, characterized in that, It includes a processor and a memory, the memory being used to store a computer program, and the processor being used to call and run the computer program stored in the memory to perform the method for detecting internal corrosion and water accumulation in a column as described in any one of claims 1 to 5.

7. A system for detecting internal corrosion and water accumulation in a column, characterized in that, include: An ultrasonic transmitter, an ultrasonic receiver, and a column internal corrosion and water accumulation detection terminal as described in claim 6; The ultrasonic transmitter is used to transmit ultrasonic signals toward the target column. The ultrasonic receiver is used to acquire the ultrasonic echo signal reflected by the target column and send the ultrasonic echo signal reflected by the target column to the detection terminal.

8. The column internal corrosion and water accumulation detection system according to claim 7, characterized in that, The ultrasonic transmitter includes an ultrasonic probe and a water film layer; the water film layer is disposed at the front end of the ultrasonic probe.

Images