Method for evaluating electromagnetic emission of stress evolution of concrete dam structure

Abstract

The application provides an electromagnetic emission evaluation method for stress evolution of a concrete dam structure, comprising the following steps: electromagnetic emission signal collecting devices are arranged at different measuring points in a stress monitoring area of the concrete dam, and electromagnetic induction antennas for measuring three axial directions are configured, so as to continuously collect electromagnetic emission signals in space; the directions of the collecting devices are kept consistent, and the electromagnetic emission signals in a period of time are collected; the collected signals are respectively passed through low-pass filters and high-pass filters, so that electromagnetic emission signals of three axial directions are obtained, and the electromagnetic emission signals of three axial directions are combined into total electromagnetic emission signals, thereby obtaining low-frequency and high-frequency electromagnetic signals of different measuring points; the amplitude, amplitude change amount of the low-frequency electromagnetic emission signals and the amplitude of the high-frequency electromagnetic emission signals are analyzed, so as to determine the position, intensity, change rate and evolution direction of stress concentration in the stress monitoring area of the concrete dam structure. The application can effectively monitor the stress concentration area of the concrete dam, and improves the safety and stability of the concrete dam structure.

Description

Technical Field

[0001] This application relates to the field of structural safety monitoring technology, and in particular to an electromagnetic emission assessment method and device for stress evolution of concrete dam structures. Background Technology

[0002] The structural safety of concrete dams is crucial for the stable operation of hydropower stations. Under the influence of external forces or environmental factors, the stress inside the dam will change over time, leading to stress concentration and, under further stress, cracking or even dam collapse. Currently, stress evolution is mainly monitored using strain gauges, requiring the pre-installation of strain sensors inside the concrete dam structure; otherwise, it is difficult to monitor changes in internal stress.

[0003] In related technologies, for example, a method for the damage evolution of recycled concrete based on the cumulative number of acoustic emission events monitors damage to concrete structures using acoustic emission. However, this monitoring method requires close contact with the concrete structure surface, limiting the monitoring range. Another example is a method and device for stress-strain analysis of concrete dams based on multi-point combined calculations. This method analyzes the vertical changes of the concrete dam through a multi-point stress-strain system to determine the overall stress changes in the dam foundation. However, this method is difficult to assess and predict internal stress changes. Yet another example is a method for analyzing the movement and failure characteristics of overlying strata. This method establishes a monitoring and analysis method for stress evolution through simulation analysis. However, it mainly utilizes microseismic sensors, making it difficult to achieve comprehensive prediction of stress in concrete dams. Summary of the Invention

[0004] This application aims to at least partially address one of the technical problems in the related art.

[0005] Therefore, the first objective of this application is to propose an electromagnetic emission assessment method for stress evolution in concrete dam structures, which can effectively monitor stress concentration areas in concrete dams and improve the safety and stability of concrete dam structures.

[0006] The second objective of this application is to propose a computer device.

[0007] The third objective of this application is to provide a non-transitory computer-readable storage medium.

[0008] To achieve the above objectives, the first aspect of this application proposes an electromagnetic emission assessment method for stress evolution in concrete dam structures, comprising:

[0009] Electromagnetic emission signals are acquired through an electromagnetic emission signal acquisition device, which is located at a measuring point in the stress monitoring area of ​​the concrete dam. The device is equipped with an electromagnetic induction antenna that measures three axes (x, y, and z) to continuously acquire electromagnetic emission signals in space. The three axes (x, y, and z) of the device remain consistent during signal acquisition.

[0010] For each measuring point, the electromagnetic emission signal collected by the device is passed through a low-pass filter and a high-pass filter respectively to obtain the triaxial electromagnetic emission signal S. Lx S Ly S Lz and S Hx S Hy S Hz The electromagnetic emission signals from the three axes are combined to obtain the low-frequency electromagnetic emission signal S at each measuring point. L and high-frequency electromagnetic emission signal S H ;

[0011] Based on the amplitude of the low-frequency electromagnetic emission signal at all measuring points, the location and intensity of stress concentration in the monitoring area of ​​the concrete dam are determined.

[0012] Based on the amplitude variation of the low-frequency electromagnetic emission signal at all measuring points, the rate of change of stress concentration in the monitoring area of ​​the concrete dam is determined.

[0013] Based on the amplitude of the high-frequency electromagnetic emission signal at all measuring points, the evolution direction of stress concentration in the monitoring area of ​​the concrete dam is determined.

[0014] To achieve the above objectives, a second aspect of the present invention provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-mentioned electromagnetic emission assessment method for stress evolution of concrete dam structures.

[0015] To achieve the above objectives, a third aspect of the present invention provides a non-transitory computer-readable storage medium that, when the instructions in the storage medium are executed by a processor, enables the execution of an electromagnetic emission assessment method for stress evolution of a concrete dam structure.

[0016] The electromagnetic emission assessment method and apparatus for stress evolution of concrete dam structures in this application collect electromagnetic emission signals around the concrete dam and perform low-frequency and high-frequency component analysis on the signals. By comparing the magnitude of the signal amplitude and the rate of change of amplitude at different measuring points, the method determines various indicators such as the concentration location, intensity, trend of change, and direction of stress in the concrete dam structure, thereby ensuring the safe and stable operation of the concrete dam and having broad application prospects.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 This is a flowchart illustrating an electromagnetic emission assessment method for stress evolution of a concrete dam structure provided in Embodiment 1 of this application.

[0020] Figure 2 A schematic diagram of another electromagnetic emission assessment method for stress evolution of concrete dam structures provided in this application embodiment;

[0021] Figure 3 This is a schematic diagram of the layout of measuring points in the stress monitoring area of ​​a concrete dam structure according to an embodiment of this application;

[0022] Figure 4 This is a schematic diagram of the high-frequency and low-frequency separation of electromagnetic transmission signals of a concrete dam according to an embodiment of this application. Detailed Implementation

[0023] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0024] The electromagnetic emission assessment method and apparatus for stress evolution of concrete dam structures according to embodiments of this application are described below with reference to the accompanying drawings.

[0025] Figure 1 This is a flowchart illustrating an electromagnetic emission assessment method for stress evolution in a concrete dam structure, as provided in Embodiment 1 of this application.

[0026] like Figure 1 As shown, the electromagnetic emission assessment method for stress evolution of this concrete dam structure includes the following steps:

[0027] Step 101: Electromagnetic emission signals are acquired using an electromagnetic emission signal acquisition device. The device is located at a measuring point in the stress monitoring area of ​​the concrete dam. The device is equipped with an electromagnetic induction antenna that measures three axes (x, y, z) for continuous acquisition of electromagnetic emission signals in space. The x, y, and z axes of the device remain consistent during signal acquisition.

[0028] Step 102: For the device at each measuring point, pass the acquired electromagnetic emission signal through a low-pass filter and a high-pass filter respectively to obtain the triaxial electromagnetic emission signal S. Lx S Ly S Lz and S Hx S Hy S Hz The electromagnetic emission signals of the three axes are combined to obtain the low-frequency electromagnetic emission signal SL and the high-frequency electromagnetic emission signal SH at each measuring point;

[0029] Step 103: Based on the amplitude of the low-frequency electromagnetic emission signal at all measuring points, determine the location and intensity of stress concentration in the monitoring area of ​​the concrete dam.

[0030] Step 104: Based on the amplitude change of the low-frequency electromagnetic emission signal at all measuring points, determine the rate of change of stress concentration in the monitoring area of ​​the concrete dam.

[0031] Step 105: Based on the amplitude of the high-frequency electromagnetic emission signal at all measuring points, determine the evolution direction of stress concentration in the monitoring area of ​​the concrete dam.

[0032] The electromagnetic emission assessment method for stress evolution of concrete dam structures in this application collects electromagnetic emission signals around the concrete dam and performs low-frequency and high-frequency component analysis on the signals. By comparing the magnitude of the signal amplitude and the rate of change of amplitude at different measuring points, it determines various indicators such as the concentration location, intensity, trend of change, and direction of stress in the concrete dam structure, ensuring the safe and stable operation of the concrete dam and has broad application prospects.

[0033] Figure 2 A schematic diagram illustrating the principle of another electromagnetic emission assessment method for stress evolution of concrete dam structures provided in this application embodiment. Figure 2 As shown, it includes:

[0034] S1: At measuring points A, B, C, and D in the stress monitoring area of ​​the concrete dam, an electromagnetic emission signal acquisition device is set up, equipped with an electromagnetic induction antenna capable of measuring three axes, to continuously acquire electromagnetic emission signals in space. The area enclosed by the line connecting measuring points A, B, C, and D surrounds the monitoring area, and the arrangement of the measuring points is as follows: Figure 3 As shown, the coordinates of measuring point A are (0, 1, 0), the coordinates of measuring point B are (1, 3, 0), the coordinates of measuring point C are (4, 1, 0), and the coordinates of measuring point D are (1, 1, 2.5).

[0035] S2: Keep the x, y, and z axes of the electromagnetic emission signal acquisition device aligned. In this embodiment, the x-axis is aligned with the due east direction, the y-axis is aligned with the due north direction, and the z-axis is vertically upward and perpendicular to the horizontal plane. Start the electromagnetic emission signal acquisition device and the electromagnetic emission signal data analysis terminal to collect electromagnetic emission signals for 1 hour.

[0036] S3: The acquired electromagnetic emission signal is passed through a low-pass filter and a high-pass filter, respectively. The upper cutoff frequency of the low-pass filter is 10Hz, and the lower cutoff frequency of the high-pass filter is 1kHz, to obtain the triaxial electromagnetic emission signal S. Lx S Ly S Lz and S Hx S Hy S Hz In this embodiment, the separation process of some low-frequency and high-frequency electromagnetic signals is as follows: Figure 4 As shown;

[0037] S4: Combine the electromagnetic emission signals from the three axes into a total electromagnetic emission signal S. L and S H The low-frequency and high-frequency electromagnetic signals S from the four electromagnetic emission signal acquisition devices were obtained. LA S LB S LC S LD S HA S HB S HC S HD The formulas for calculating low-frequency and high-frequency electromagnetic signals are:

[0038]

[0039] In the calculation, S Lx S Ly S Lz The amplitude is used in the calculation.

[0040] S5: Analyze the amplitude of low-frequency electromagnetic emission signals acquired by different electromagnetic emission acquisition devices. To determine the location and intensity of stress concentration in the monitoring area of ​​a concrete dam, the locations of four measurement points A, B, C, and D are (x1, y1, z1), (x2, y2, z2), (x3, y3, z3), and (x4, y4, z4), respectively. The location of stress concentration P is (x0, y0, z0), and the intensity of the stress concentration is S. Then,

[0041] The distances between PA, PB, PC, and PD are as follows:

[0042]

[0043] The intensity S of stress concentration can be expressed as:

[0044]

[0045] In this embodiment, the positions of points A, B, C, and D can be used to solve for the solution. The values ​​are 2V, 0.5V, 0.32V, and 0.22V respectively. After calculation, the stress concentration location P is (1, 1, 0), and the intensity S is 2V.

[0046] S6: Analyze the amplitude variation S of low-frequency electromagnetic emission signals acquired by different electromagnetic emission acquisition devices. LA_delta S LB_delta S LC_delta S LD_delta Determine the rate of change S of stress concentration in the monitoring area of ​​the concrete dam. delta The maximum value of the low-frequency electromagnetic emission signal is Max. s The minimum value is Min s Then the change in amplitude S LA_delta for:

[0047] S LA_delta =Max s -Min s

[0048]

[0049] In this embodiment, S LA_delta S LB_delta S LC_delta S LD_delta The stress concentration rate S is 0.1 V / h, 0.13 V / h, 0.03 V / h, and 0.09 V / h, respectively. delta It is 0.0875V / h;

[0050] S7: Analyze the amplitude of high-frequency electromagnetic emission signals acquired by different electromagnetic emission acquisition devices. Determine the evolution direction F of stress concentration in the monitoring area of ​​the concrete dam. The stress evolution direction F is (x F y F , z F Let the distances between PA, PB, PC, and PD be DA, DB, DC, and DD, respectively. Then the angles between F and the lines connecting PA, PB, PC, and PD are θ1, θ2, θ3, and θ4, respectively.

[0051]

[0052] High-frequency electromagnetic transmission signals can be represented as:

[0053]

[0054] In this embodiment, the angles between F and the lines connecting PA, PB, PC, and PD are θ1, θ2, θ3, and θ4, respectively, which are 116°, 26°, 63°, and 90°, and the amplitudes are... The stress concentration values ​​were 0.90V, 0.11V, 0.10V, and 0.16V, respectively, with the evolution direction of stress concentration being (1, 2, 0). The final location of the stress concentration area in the concrete dam structure was determined to be (1, 1, 0), with a strength of 2V, a rate of change of 0.0875V / h, and an evolution direction of (1, 2, 0). By comparing the stress change information of the stress concentration area with the stress information during normal operation, the condition of the concrete structure can be assessed.

[0055] To implement the above embodiments, the present invention also proposes a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the methods described in the above embodiments.

[0056] To implement the above embodiments, the present invention also proposes a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method of the above embodiments.

[0057] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0058] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0059] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0060] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0061] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0062] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0063] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0064] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. An electromagnetic emission assessment method for stress evolution in concrete dam structures, characterized in that, include: Electromagnetic emission signals are acquired using an electromagnetic emission signal acquisition device, wherein the device is arranged at the measuring point in the stress monitoring area of ​​the concrete dam, and the device is equipped with an electromagnetic induction antenna that measures three axes x, y, and z, for continuously acquiring electromagnetic emission signals in space, and the three axes x, y, and z of the device remain consistent during signal acquisition. For each measuring point, the electromagnetic emission signal collected by the device is passed through a low-pass filter and a high-pass filter respectively to obtain the triaxial electromagnetic emission signal S. Lx S Ly S Lz and S Hx S Hy S Hz The electromagnetic emission signals from the three axes are combined to obtain the low-frequency electromagnetic emission signal S at each measuring point. L and high-frequency electromagnetic emission signal S H ; Based on the amplitude of the low-frequency electromagnetic emission signal at all measuring points, the location and intensity of stress concentration in the monitoring area of ​​the concrete dam are determined, including: Suppose there are n measuring points, and the location of the nth measuring point is... The stress concentration location P is The stress concentration intensity is S, and the distance between the nth measuring point and P is: The intensity S of stress concentration is expressed as: in, For the first Low-frequency electromagnetic emission signals at each measuring point Represents low-frequency electromagnetic emission signals The amplitude; Solve the equations for the distances between n measuring points and P, along with the strength equation for stress concentration, to determine the location P of the stress concentration. and the intensity S of stress concentration; Based on the amplitude changes of low-frequency electromagnetic emission signals at all measuring points, the rate of change of stress concentration in the monitoring area of ​​the concrete dam is determined, including: The rate of change of stress concentration in the monitoring area of ​​the concrete dam is: Where n represents n measurement points, This represents the change in amplitude at the nth measuring point. for: in, , The maximum and minimum amplitude values ​​of the low-frequency electromagnetic emission signal at the nth measurement point are given. Based on the amplitude of the high-frequency electromagnetic emission signal at all measuring points, the evolution direction of stress concentration in the monitoring area of ​​the concrete dam is determined, including: Suppose there are n measuring points, and the location of the nth measuring point is... The stress concentration location P is The direction of stress evolution F is The distance between the nth measuring point and the stress concentration location P is F and The angle between the lines is , is represented as: The equation for a high-frequency electromagnetic transmission signal is: in, Indicates the first The amplitude of the high-frequency electromagnetic emission signal at each measuring point; Solving the equations for the included angle of the connecting lines and the high-frequency electromagnetic emission signal simultaneously yields the stress evolution direction F.

2. The method as described in claim 1, characterized in that, The monitoring points selected for the stress monitoring area of ​​the concrete dam include: The area enclosed by the line connecting the selected measuring points shall surround the monitoring area, and the maximum distance between the measuring points shall not exceed the preset threshold. The measurement of the three axes refers to the measurement of electromagnetic transmission signals along the x, y, and z axes using an electromagnetic induction antenna in a Cartesian rectangular coordinate system.

3. The method as described in claim 1, characterized in that, The upper cutoff frequency of the low-pass filter is 10Hz, and the lower cutoff frequency of the high-pass filter is 1kHz.

4. The method as described in claim 1, characterized in that, Low-frequency electromagnetic emission signal S L High-frequency electromagnetic transmission signals The synthesis formula is: The electromagnetic emission signals from the three axes are combined to obtain the low-frequency electromagnetic emission signal at each measurement point, including: Substitute the amplitudes of the electromagnetic emission signals along the x, y, and z axes at each measuring point into the synthesis formula for the low-frequency electromagnetic emission signal to obtain the low-frequency electromagnetic emission signal at each measuring point. The electromagnetic emission signals from the three axes are combined to obtain the high-frequency electromagnetic emission signal at each measurement point, including: Substituting the amplitudes of the electromagnetic emission signals along the x, y, and z axes at each measuring point into the synthesis formula for the high-frequency electromagnetic emission signal yields the high-frequency electromagnetic emission signal at each measuring point.

5. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the method as described in any one of claims 1-4.

6. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-4.

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