Concrete structure imaging method, device and equipment based on ultrasonic array
By calculating the propagation path of the effective signal point of the ultrasonic time series signal acquisition and mapping the signal value to the radiation pattern composed of the propagation position, the problem of high calculation in the prior art is solved and more efficient concrete structure imaging is achieved.
Patent Information
- Application Number
- CN202411777408.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-03-14
AI Technical Summary
In the prior art, the concrete structure imaging method based on the full focus algorithm has a large amount of calculation and is slightly redundant, especially when processing a sensor array with a number of arrays M, the (M-1)×M channel signal data is generated, resulting in a significant increase in the calculation amount.
By calculating the propagation path of the effective signal points of the ultrasonic time series signal acquisition, and mapping the signal value to the radiation pattern composed of the propagation position, and finally uniformly discretized to a unified superimposed grid point for superposition, the imaging calculation amount is reduced.
The imaging calculation amount is reduced and the full focus data processing efficiency is improved. Specifically, only K×(M-1) propagation radiation paths need to be calculated, which significantly reduces the calculation amount compared to the traditional method.
Smart Images
Figure CN119619299A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of nondestructive testing of civil engineering, and in particular to a method, a device and equipment for imaging a concrete structure based on an ultrasonic array. Background Art
[0002] Concrete is a basic material for civil engineering. In the long-term use, it is inevitable that it will be damaged or destroyed due to stress loads, wind and water erosion, fatigue and aging. Regular inspection and evaluation of concrete structures can effectively prevent structural instability and damage and avoid economic and property damage. The full focusing algorithm, as a non-destructive ultrasonic imaging technology, can be used for the detection of concrete structures. It simulates the propagation process of ultrasonic waves in concrete structures, uses ultrasonic signals emitted and received at multiple different angles, and synthesizes these signals through mathematical calculations to obtain an ultrasonic image of any point inside the concrete structure, and then analyzes the damage of the concrete structure based on the ultrasonic image.
[0003] The traditional full-focus calculation method is based on the grid points in the imaging image. The amplitude of each grid point in each signal is calculated and superimposed as the actual amplitude of the point. Since most time points do not coincide with the sampling time points, interpolation calculations are required. For a sensor array with an array number of M, the acquisition method of one channel transmitting and the rest receiving will generate (M-1)×M channels of signal data. Assuming that there are N discrete grid points, after reducing repeated calculations based on acoustic reciprocity, it is still necessary to calculate approximately N×(M-1)×M÷2 time points and perform interpolation calculations, which is computationally intensive and slightly redundant. Summary of the invention
[0004] Based on this, in order to solve the technical problems in the prior art, the present invention provides a method, device and equipment for concrete structure imaging based on an ultrasonic array.
[0005] The present invention provides a concrete structure imaging method based on an ultrasonic array, comprising:
[0006] Using ultrasonic array to collect ultrasonic time series signals of concrete structure ijk , A ijk represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor in the ultrasonic array;
[0007] The ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate from the i-th sensor to the j-th sensor in a straight line is regarded as a valid signal point;
[0008] Obtain ultrasonic time series signal A ijkThe propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation diagram of
[0009] The ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation diagram and superimposed to obtain the imaging result of the internal defect structure of the concrete.
[0010] Furthermore, the ultrasonic time series signal A ijk The signal points whose propagation time is greater than the time required for the ultrasonic signal to propagate linearly from the i-th sensor to the j-th sensor are regarded as valid signal points, including:
[0011] The propagation position expression formula of the kth signal point in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor is obtained:
[0012]
[0013] Among them, x i and x j are the horizontal coordinates of the i-th sensor and the j-th sensor in the ultrasonic array respectively; z is the vertical dimension coordinate, z<0, c is the wave speed; x is the focal point;
[0014] The signal point that satisfies the following equation is regarded as the ultrasonic time series signal A. ijk Valid signal points in:
[0015]
[0016] Where fs is the sampling frequency.
[0017] Furthermore, the propagation path of the effective signal point is based on the horizontal coordinate point x i and x j The propagation distance c·k / fs corresponding to the focus and time point k is half the circumference of the ellipse with the major axis length.
[0018] Furthermore, the ultrasonic time series signal A ijk The signal value of each signal point in the image is mapped to the radiation diagram and superimposed to form an image, including:
[0019] The ultrasonic time series signal A ijk The signal value of each signal point is mapped to the elliptical calculation grid points constructed based on the propagation path of the effective signal point, and then the values in the elliptical calculation grid are interpolated to the square uniform superposition discrete grid points through two-dimensional discretization;
[0020] All ultrasonic signals are superimposed on the square uniform superposition discrete grid points to obtain the ultrasonic amplitudes on the grid points in the square uniform superposition discrete grid.
[0021] Furthermore, the ultrasonic time series signal A ijk The radiation pattern is A ijk The result is obtained by combining the half ellipse circumference corresponding to each valid signal point in .
[0022] Furthermore, the imaging result of the internal defect structure of the concrete has an imaging range defined by the range of the minimum radiation image among all the radiation images, so as to ensure that the imaging area is formed by the superposition of all sensor signal data.
[0023] Furthermore, the sensors are dry-coupled shear wave probes of the same type and with consistent performance, arranged in a one-dimensional linear ultrasonic array to perform B-scan detection of concrete in the direction of the sensor axis.
[0024] The present invention provides a concrete structure imaging device based on an ultrasonic array, comprising:
[0025] A data acquisition module is used to collect ultrasonic time series signals A of concrete structures using an ultrasonic array. ijk , A ijk represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor in the ultrasonic array;
[0026] Signal filtering module, used to filter the ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate from the i-th sensor to the j-th sensor in a straight line is regarded as a valid signal point;
[0027] Radiation pattern acquisition module, used to obtain ultrasonic time series signal A ijk The propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation diagram of
[0028] Data visualization module, used to visualize the ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation diagram and superimposed to obtain the imaging result of the internal defect structure of the concrete.
[0029] The present invention provides a computer device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned concrete structure imaging method based on ultrasonic array when executing the program.
[0030] At least one of the above technical solutions adopted by the present invention can achieve the following beneficial effects:
[0031] In the ultrasonic array-based concrete structure imaging method provided by the present invention, compared with the conventional method of calculating discrete grid points, the present invention reduces the amount of calculation by calculating the propagation path of the effective signal point. Specifically: select the effective sampling signal points whose propagation time in each signal is greater than the specified range, calculate and map the corresponding propagation path, and finally discretize them to a unified superposition grid point for superposition. After obtaining the actual propagation speed of the concrete, since the actual distance of the sensor array with M columns is only M-1, the sampling frequency of each signal is fixed. If the number of effective signal sampling points that meet the imaging range is K, it is actually only necessary to calculate K×(M-1) propagation radiation paths, which reduces the imaging calculation amount and improves the full-focus data processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:
[0033] Figure 1 A schematic diagram of a flow chart of a concrete structure imaging method based on an ultrasonic array provided by the present invention;
[0034] Figure 2 A schematic diagram of the propagation path of the sampling signal points provided by the present invention;
[0035] Figure 3 A schematic diagram of discrete grid points of a propagation path provided by the present invention;
[0036] Figure 4 A schematic diagram of uniformly superimposed discrete grid points provided by the present invention. DETAILED DESCRIPTION
[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in combination with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the specification, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0038] At present, detection methods usually revolve around acoustic, thermal, electromagnetic or X-ray technologies. However, thermal methods require a heat source; electromagnetic methods are greatly affected by internal steel bars; X-ray and other technologies require professional equipment and usually have requirements for the size of the structure to be tested. Acoustic methods are easy to operate, fast and efficient and are widely used. The full focusing algorithm is a data processing method in acoustic methods. The traditional calculation method is based on the grid points in the imaging image. The amplitude of each grid point in each signal is calculated and superimposed as the actual amplitude of the point. The calculation amount is large and slightly redundant.
[0039] Based on the drawbacks of the existing methods, the present invention proposes an improved full-focus calculation process, which changes the calculation focus from the focus point to the actual signal sampling point, calculates the propagation position of each sampling point in each signal, and maps the signal value to the radiation diagram composed of the propagation position, and finally superimposes the image to achieve the full-focus algorithm. This method is expected to optimize the calculation efficiency of the full-focus algorithm.
[0040] Example
[0041] Figure 1 The process of the concrete structure imaging method based on ultrasonic array in this embodiment is shown. Figure 1 The method is described in detail and specifically comprises the following steps:
[0042] S1: Using ultrasonic array to collect ultrasonic time series signals A from concrete structure ijk , A ijk Represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor in the ultrasonic array.
[0043] Arrange multiple sensors on the concrete surface to form a one-dimensional linear array. The concrete used for detection should have a relatively flat surface, which is sufficient to support good contact between the sensor array. The sensors use the same type and consistent performance dry-coupled shear wave probes, arranged in a one-dimensional linear array, and perform B-scan detection on the concrete in the direction of the sensor axis. Take the geometric center of the one-dimensional linear array / one-dimensional ultrasonic array set on the concrete surface as the coordinate origin, the direction of the one-dimensional ultrasonic array as the x-axis, and the ultrasonic emission direction in the one-dimensional ultrasonic array as the z-axis to establish a two-dimensional coordinate system; virtually discretize the concrete structure area to be detected, and determine the coordinates of the virtual focus for imaging in the concrete structure area to be detected after virtual discretization based on the established two-dimensional coordinate system. That is: before the detection begins, the number, spacing, wave speed and other information of the known sensor array can be used.
[0044] The traditional method of one channel transmitting and the rest receiving is adopted to collect the full matrix echo data matrix, and the improved full focusing algorithm is used to visualize the full focusing data matrix to realize the imaging of defects such as cracks and voids inside the concrete. The workflow of the improved full focusing algorithm is as follows: first, the conventional expression formula based on the focus point is rewritten into an expression formula based on the propagation position of the signal point; second, the radiation map of each group of signals is constructed based on the propagation position of the signal point; finally, the signal value is mapped to the radiation map, and the radiation map is superimposed to realize full focusing imaging. The following is a detailed description of each step of the improved full focusing algorithm.
[0045] S2: The ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate linearly from the i-th sensor to the j-th sensor is regarded as a valid signal point.
[0046] The following describes the basis for the improvement in detail:
[0047] The conventional expression formula based on the focus point is:
[0048]
[0049] Where I(x,z) represents the intensity of the focus point with coordinates (x,z) in the imaging grid; n is the number of array elements, and A ij It is the ultrasonic signal received by the jth element when the ith element excites the jth element.
[0050] According to the traditional full focusing algorithm, the propagation time t from the focus point (x, z) to the excitation array element i and the receiving array element j is ij The calculation formula for (x,z) is:
[0051]
[0052] Among them, x i 、x j are the x-coordinates of the excitation element i and the receiving element j in the ultrasonic array, respectively, z<0, and c is the wave speed. It can be seen that the actual calculation is the propagation time from the excitation sensor to the focal point and then reflected to the receiving sensor. Based on this principle, A is expressed ijk The possible propagation paths of (the signal point corresponding to time point k in the ultrasonic signal received by the i-element stimulating the j-element) are as follows:
[0053]
[0054] Among them, A ijk is the kth data in the A-scan signal received by the i-element stimulating the j-element, fs is the sampling frequency, and if k satisfies the following formula, the signal point is called a valid signal point:
[0055]
[0056] S3: Obtain ultrasonic time series signal A ijk The propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation diagram.
[0057] Visible effective signal point A ijk The corresponding propagation position expression is based on the horizontal coordinate point x i and x j is the focus, and the propagation distance corresponding to time point k is c·k / fs·half the circumference of the ellipse with the major axis length. Figure 2 The figure shows the propagation path of the sampling signal point and its corresponding propagation path. The propagation paths of multiple sampling data constitute the radiation diagram of the signal. Each valid signal point received in the signal sequence corresponds to a half elliptical path. The one-dimensional signal sequence A ij The propagation position corresponding to each valid signal point in the ij Radiation diagram.
[0058] When using an ultrasonic array for full-focus data acquisition, the spacing between arrays and the sampling frequency are usually fixed parameters, and the discrete grid points of the area to be imaged are also manually determined in advance. The only unknown parameter is the propagation speed of the ultrasonic wave. After the wave speed of the structure to be measured is determined through experiments, the propagation path corresponding to each signal point can be determined.
[0059] S4: The ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation diagram and superimposed to obtain the imaging result of the internal defect structure of the concrete.
[0060] After obtaining the full-focus data matrix, the signal value is mapped to the corresponding propagation path. Because the visualization image is based on pixel points, when performing calculations, the signal value of each signal point in the ultrasonic time series signal is mapped to the elliptical calculation grid points constructed based on the effective signal point propagation path, and then the values in the elliptical calculation grid are interpolated to the square uniform superposition discrete grid points through two-dimensional discretization; all ultrasonic signals are superimposed on the square uniform superposition discrete grid points to obtain the ultrasonic amplitude at the grid points in the square uniform superposition discrete grid. Figure 3 As shown in the figure, the signal value is mapped to the calculation grid points of the path, and then interpolated to the value as shown in the figure. Figure 4 The uniformly superimposed discrete grid points are shown. Thus, the corresponding image of each data in the full-focus data matrix is obtained, and the superposition operation can be performed on the uniformly superimposed discrete grid points to achieve full-focus imaging.
[0061] Through the traditional one channel transmission and the other channel reception, the fully focused data matrix, that is, the ultrasonic time series signal Aijk Finally, the concrete defects are imaged according to the improved full focusing algorithm. The imaging range is defined by the range of the minimum radiation map among all radiation maps. Each valid signal point received in the signal sequence corresponds to a semi-elliptical path. The propagation position corresponding to each valid signal point in the one-dimensional signal sequence Aij together constitutes the radiation map of Aij, thereby ensuring that the imaging area is formed by the superposition of all channel signal data.
[0062] The traditional full-focus processing flow needs to calculate the signal value of each grid point in each signal at the corresponding time point, and interpolation calculation is required because most of the time points do not coincide with the sampling time points. For a sensor array with an array number of M, the acquisition method of one channel transmitting and the rest receiving will generate (M-1)×M channels of signal data. Assuming that there are N discrete grid points, after reducing repeated calculations based on acoustic reciprocity, it is still necessary to calculate approximately N×(M-1)×M÷2 time points and perform interpolation calculations.
[0063] After improvements based on this method, the focus of calculation is changed to the actual signal sampling points, and the propagation position of each sampling point in each signal is calculated. There is no need to interpolate the signal in time to calculate the propagation time corresponding to the sampling point. After the imaging range is clear, the effective sampling signal points within the specified range of each signal are selected, and the corresponding propagation path is calculated and mapped. Finally, it is discretized to a unified superposition grid point for superposition. After obtaining the actual propagation speed of concrete, because there are only M-1 actual distances between arrays and the sampling frequency of each signal is fixed, if the number of signal sampling points that meet the imaging range is K, it is actually only necessary to calculate K×(M-1) propagation radiation paths, and the remaining signals only need to move the existing paths. At the same time, because the major axis of the ellipse corresponding to each signal point k As k increases, it increases in proportion to the distance between the sending and receiving points representing the focal length of the ellipse |x i -x j | is a fixed value, then the first path can be scaled proportionally when calculating the elliptical path corresponding to each signal point k. In contrast, under the same imaging accuracy, in traditional calculations, for the final unified discrete grid number N, after reducing repeated calculations based on acoustic mutual differences, it is still necessary to calculate N×(M-1)×M÷2 time points, and the number of signal points K used to calculate the path will be significantly smaller than the final unified discrete grid number N. This can be seen from Figure 4 It is supported by Figure 4 Expressed as equal imaging accuracy (the discrete point interval is approximately the path interval, that is, the distance corresponding to one sampling interval, c / fs), where the number of discrete grid points N is approximately the square of the number of paths K (N is approximately equal to K 2 , the actual ratio needs to be limited according to the actual imaging range), usually the discrete points will be denser, that is, N>K 2,If the precision is reduced, the number of paths can also be reduced (one such path is taken every other path), so this argument is valid. This method will reduce the amount of imaging calculation and improve the efficiency of all-focus data processing.
[0064] The above is a concrete structure imaging method based on an ultrasonic array provided by one or more embodiments of the present invention. Based on the same idea, the present invention also provides a corresponding concrete structure imaging device based on an ultrasonic array, including:
[0065] A data acquisition module is used to collect ultrasonic time series signals A of concrete structures using an ultrasonic array. ijk , A ijk Represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor in the ultrasonic array.
[0066] Signal filtering module, used to filter the ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate linearly from the i-th sensor to the j-th sensor is regarded as a valid signal point.
[0067] Radiation pattern acquisition module, used to obtain ultrasonic time series signal A ijk The propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation diagram.
[0068] Data visualization module, used to visualize the ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation diagram and superimposed to obtain the imaging result of the internal defect structure of the concrete.
[0069] For the specific definition of the concrete structure imaging device based on ultrasonic array, please refer to the definition of the concrete structure imaging method based on ultrasonic array in the above text, which will not be repeated here. Each module in the above concrete structure imaging device based on ultrasonic array can be implemented in whole or in part by software, hardware and their combination. The above modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.
[0070] The present invention also provides a computer device structure. At the hardware level, the computer device includes a processor, an internal bus, a network interface, a memory, and a non-volatile memory. Of course, it may also include other hardware required for the business. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it to achieve the above Figure 1 A concrete structure imaging method based on ultrasonic array is provided.
[0071] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).
[0072] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of the present invention.
Claims
1. A method for imaging concrete structures based on ultrasonic array, characterized in that: include: Acquisition of ultrasonic time series signals of concrete structures using ultrasonic arrays ijk , A ijk represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the i-th sensor in the ultrasonic array; The ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate from the i-th sensor to the ,th sensor in a straight line is regarded as a valid signal point; Obtain ultrasonic time series signal A ijk The propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation pattern; The ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation pattern and superimposed to obtain the imaging result of the internal defect structure of the concrete.
2. The method for imaging concrete structures based on ultrasonic array according to claim 1, characterized in that: The ultrasonic time series signal A ijk The signal points whose propagation time is greater than the time required for the ultrasonic signal to propagate from the i-th sensor to the i-th sensor in a straight line are regarded as valid signal points, including: The formula for obtaining the propagation position of the kth signal point in the ultrasonic signal emitted by the i-th sensor and received by the k-th sensor is: Among them, x i and x j are the horizontal coordinates of the i-th sensor and the j-th sensor in the ultrasonic array, respectively; z is the vertical dimension coordinate, z < 0, c is the wave speed; x is the focal point; The signal point that satisfies the following equation is regarded as the ultrasonic time series signal A. ijk Valid signal points in: Where fs is the sampling frequency.
3. The method for imaging concrete structures based on ultrasonic array according to claim 2, characterized in that: The propagation path of the effective signal point is based on the horizontal coordinate point x i and x j The propagation distance c·k / fs corresponding to the focus and time point k is half the circumference of the ellipse with the major axis length.
4. The method for imaging concrete structures based on ultrasonic array according to claim 3, characterized in that: The ultrasonic time series signal A ijk The signal values of each signal point in the image are mapped to the radiation pattern and superimposed to form an image, including: The ultrasonic time series signal A ijk The signal value of each signal point is mapped to the elliptical calculation grid points constructed based on the effective signal point propagation path, and then the values in the elliptical calculation grid are interpolated to the square uniform superposition discrete grid points through two-dimensional discretization; All ultrasonic signals are superimposed on the square uniform superposition discrete grid points to obtain the ultrasonic amplitudes on the grid points in the square uniform superposition discrete grid.
5. The method for imaging concrete structures based on ultrasonic array according to claim 3, characterized in that: The ultrasonic time series signal A ijk The radiation pattern is A ijk The result is obtained by combining the half ellipse circumference corresponding to each valid signal point in .
6. The method for imaging concrete structures based on ultrasonic array according to claim 5, characterized in that: The imaging result of the internal defect structure of the concrete has an imaging range defined by the range of the minimum radiation pattern among all radiation patterns, so as to ensure that the imaging area is formed by the superposition of all sensor signal data.
7. The method for imaging concrete structures based on ultrasonic array according to claim 1, characterized in that: The sensors are dry-coupled shear wave probes of the same type and with consistent performance, arranged in a one-dimensional linear ultrasonic array to perform B-scan detection of concrete in the direction of the sensor axis.
8. A concrete structure imaging device based on an ultrasonic array, characterized in that: include: The data acquisition module is used to collect ultrasonic time series signals A of the concrete structure using an ultrasonic array. ijk , A ijk represents the signal point corresponding to time point k in the ultrasonic signal emitted by the i-th sensor and received by the j-th sensor in the ultrasonic array; Signal filtering module, used to filter the ultrasonic time series signal A ijk The signal point whose propagation time is greater than the time required for the ultrasonic signal to propagate from the i-th sensor to the ,th sensor in a straight line is regarded as a valid signal point; Radiation pattern acquisition module, used to obtain ultrasonic time series signal A ijk The propagation paths of all valid signal points in the , and the propagation paths of all valid signal points are combined to obtain the ultrasonic time series signal A ijk Radiation pattern; Data visualization module is used to visualize the ultrasonic time series signal A ijk The signal value of each signal point is mapped to the radiation pattern and superimposed to obtain the imaging result of the internal defect structure of the concrete.
9. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 7 is implemented.