Stay cable wind vibration noise acoustic emission monitoring method and system

Abstract

The invention discloses a stay cable wind vibration noise acoustic emission monitoring method and system, and is applied to the technical field of intelligent monitoring, and the method comprises the steps: firstly, selecting a nondestructive stay cable model in a laboratory, simulating wind-induced vibration, and collecting cable wind vibration noise acoustic emission signals through an acoustic emission instrument and the like; analyzing acoustic emission signal characteristics of the wind vibration noise of the inhaul cable under different external excitation amplitudes and excitation frequencies; a key monitoring node layout is constructed, acoustic emission signal characteristics of inhaul cable wind vibration noise at different key specific positions are studied, and a laboratory method is expanded to an in-service stay cable according to wind vibration noise acoustic emission signals, the monitoring node layout and the acoustic emission signal characteristics. Sound emission characteristic parameters are selected according to a random forest characteristic importance selection method, and correlation analysis is carried out; the identification of the stay cable wind vibration noise acoustic emission signal is realized, so that the problem that the structural damage is difficult to effectively identify and represent due to confusion of the wind vibration noise signal and the structural damage signal in a stay cable field health monitoring test is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of health monitoring of inclined cables, and in particular to a method and system for monitoring wind-induced vibration noise and acoustic emission of inclined cables. Background Art

[0002] In practical applications, structural health monitoring signals are often affected by various noises, which can cause the quality of the signal to deteriorate. The noise components can interfere with the feature extraction of the signal, thus affecting the signal processing and recognition. The fault characteristics of wind turbines can be introduced into the strong background noise from the wind turbine, which makes it difficult to extract the fault characteristics in subsequent diagnosis. In previous studies, wind vibration noise was measured by free-field microphones, microphones that can convert sound pressure into electrical signals, or accelerometers. Automobile developers can now optimize and control the noise of tires, engines, and mechanical system transmissions within a reasonable range, so wind vibration noise has become the main noise source for research and control. Previous studies have monitored the wind vibration noise in cars through microphones and microphones. Previous studies have shown that when monitoring various parts of high-speed trains, pantographs are the largest noise source of wind vibration noise in high-speed trains. Previous studies have monitored the pantograph wind vibration noise through microphone arrays and acoustic sensors.

[0003] The above research is a monitoring method for wind-induced vibration noise caused by wind load and wind-induced vibration in various structures. Since cable-stayed bridges are often arranged in conditions such as wide terrain, strong wind, and high altitude, the wind-induced vibration problem and wind-induced vibration noise of the cable are also inevitable due to the characteristics of the environment in which the cable is located, its own dynamic characteristics, and the interaction between the wind load and the cable structure. When monitoring wind-induced vibration noise in the above-mentioned structures, free-field microphones, microphones, accelerometers, microphone arrays, acoustic sensors and other instruments are usually used. Acoustic emission monitoring technology is a passive, non-destructive real-time monitoring method, and its application and development are becoming more and more extensive. The monitoring objects of this technology include damage monitoring in the field of structural health monitoring of rocks, metals, masonry, concrete, composite materials, etc. At the same time, the signals collected by the acoustic emission probes arranged on the surface of the structure not only include structural damage, but also environmental noise signals caused by other reasons. The advantages of acoustic emission technology are obvious, but it has the disadvantage of being easily affected by wind vibration noise acoustic emission signals. Therefore, it is extremely important to conduct a comprehensive analysis of wind vibration noise acoustic emission signals in acoustic emission technology, and then eliminate the influence of wind vibration noise acoustic emission signals in the monitoring process of acoustic sensors.

[0004] In view of the above, the present application provides a method and system for monitoring wind-induced noise and acoustic emission of a stay cable to solve the above problems. Summary of the invention

[0005] In order to overcome the above-mentioned shortcomings in the prior art, the present invention provides an acoustic emission monitoring method for wind-induced vibration noise of a cable, which can accurately monitor and identify the noise caused by wind vibration of the cable in a large noise background. Although the acoustic emission technology has the advantages of non-invasiveness and real-time monitoring, it is easily affected by wind vibration noise. Therefore, it is necessary to optimize the acoustic emission technology to eliminate or reduce the influence of such noise and improve the efficiency and accuracy of structural health monitoring.

[0006] A method for monitoring acoustic emission of wind-induced vibration noise of a stay cable, characterized by comprising:

[0007] S1: A non-damaged cable model is selected in the laboratory, wind-induced vibration is simulated by a servo motor, and the acoustic emission signal of the wind-induced vibration noise of the cable is collected by an acoustic emission monitoring system. The acoustic emission signal characteristics of the wind-induced vibration noise of the cable at multiple monitoring points at different longitudinal positions of the cable under different external excitation conditions are analyzed;

[0008] S2: Based on the analysis results of the acoustic emission signal characteristics of the wind-induced vibration noise of the cables in S1 and the centrally symmetrical structural characteristics of the cable model in S1, a layout of key monitoring nodes is constructed;

[0009] S3: deploying the acoustic emission monitoring system in S1 and the key monitoring nodes in S2 on the cables of the in-service cable-stayed bridge to collect the acoustic emission signals of the noise of the cables of the in-service cable-stayed bridge;

[0010] S4: Select the characteristic parameters of the acoustic emission signal in S3 based on the importance selection method of the random forest algorithm, and perform correlation analysis to realize the acoustic emission signal recognition of the wind-induced vibration noise of the inclined cable.

[0011] Furthermore, the method for simulating wind-induced vibration by a servo motor in S1 is as follows: one end of an elastic rope is fixed at the mid-span position of the cable of the cable model, and the other end is fixed to the rotating rod of the servo motor; the rotation of the rotating rod is converted into harmonic excitation by the elastic rope, thereby exciting the vibration of the corresponding mode of the cable, the external simulated excitation frequency is adjusted by changing the speed of the servo motor, and the external simulated excitation amplitude is adjusted by changing the length of the rotating rod. In order to ensure that the experimental conditions can simulate the situations that may occur in the real environment, the vibration frequency of the external simulated excitation amplitude is set in a wider frequency range, gradually increasing from 0.5 Hz to 3.5 Hz.

[0012] Furthermore, the acoustic emission signal characteristic analysis process in S1 specifically includes the following steps:

[0013] S1-1: collecting the acoustic emission signal of the wind vibration noise of the cable, and performing preprocessing including noise removal and filtering to ensure the quality of the acoustic emission signal;

[0014] S1-2: Analyze the main frequency and frequency band distribution range of the acoustic emission signal of the cable wind vibration noise through fast Fourier transform, including frequency domain analysis and time domain analysis;

[0015] S1-3: The acoustic emission signal characteristics of the cable wind-vibration noise analyzed in S1-2 include spectral characteristics and time domain characteristics. The characteristic parameters of the two characteristics include peak frequency, bandwidth, amplitude, amplitude, duration, RMS, and ASL. The global spectral characteristics of the acoustic emission signal of the cable wind-vibration noise are obtained, including statistical characteristics and spectral characteristics.

[0016] Furthermore, constructing the layout of key monitoring nodes in S2 includes selecting the positions L / 2, L / 3, L / 4, L / 6, and L / 12 in the lower half of the cable model upward in sequence as key monitoring nodes, where L is the length of the cable.

[0017] Furthermore, the S4 specifically includes the following steps:

[0018] S4-1: Mix the cable wire breakage signal and wind vibration noise signal in the laboratory, and collect the characteristic parameters of the mixed acoustic emission signal including peak frequency, bandwidth, energy, amplitude, duration, RMS, and ASL;

[0019] S4-2: Evaluate the importance of each feature parameter based on the random forest algorithm and select important key feature parameters;

[0020] S4-3: Based on the random forest algorithm, the classification model is trained using the key characteristic parameters in S4-2 to separate the damage acoustic emission signal of the cable from the wind vibration noise acoustic emission signal of the cable.

[0021] Furthermore, the important key characteristic parameters in S4-2 include impact rate, ASL, amplitude, and RMS.

[0022] The acoustic emission monitoring system used in the acoustic emission monitoring method for wind-induced vibration noise of the inclined cable is characterized by comprising:

[0023] The acoustic emission sensor is in direct contact with the bridge cable, and is used to collect the acoustic emission signal emitted by the detected cable and transmit the acoustic signal to the acoustic emission acquisition card;

[0024] The preamplifier is used to amplify the intensity of the acoustic signal transmitted over a long distance several times and output the analog signal to the acoustic emission sensor, and adopts a single-ended input method;

[0025] Acoustic emission acquisition card, used to collect acoustic signals from acoustic emission sensors;

[0026] The computer host is used to process, record and analyze the acoustic emission signals collected by the acoustic emission acquisition card.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0028] (1) It effectively realizes the targeted monitoring node layout of the cable monitoring position and realizes the identification of wind vibration noise acoustic emission signals, providing data support and theoretical guidance for the health monitoring of the cable, which can greatly reduce the interference of wind vibration noise on the cable monitoring system and more effectively capture the real damage signal;

[0029] (2) By separating wind noise from damage signals, it is possible to detect damage to cable-stayed bridges early, prevent structural failure, and improve the safety and reliability of bridges;

[0030] (3) Distinguishing wind noise from damage signals to prevent false alarms or missed alarms helps maintenance personnel to detect potential problems in a timely manner, reduce maintenance costs, and avoid catastrophic accidents. At the same time, early detection and repair of damage can extend the service life of cables and bridges and reduce the need for large-scale repairs or replacements. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a flow chart of the acoustic emission monitoring method of wind-induced vibration noise of the inclined cable according to the present invention;

[0032] Figure 2 Schematic diagram of the method and system for monitoring wind-induced vibration noise acoustic emission of the cable according to the present invention;

[0033] Figure 3 This is a schematic diagram of arranging acoustic emission sensors at the transverse position of the inclined cable of the present invention;

[0034] Figure 4 This is a schematic diagram of arranging acoustic emission sensors in the longitudinal position of the inclined cable of the present invention;

[0035] Figure 5 A schematic diagram of arranging acoustic emission sensors near the bridge tower and in the anchoring area of ​​the present invention;

[0036] Figure 6 A feature importance selection diagram of a random forest for classifying wind-induced vibration noise and damage signals of a stay cable according to the present invention;

[0037] Figure 7 It is the spectrum diagram of the key nodes of the model of the present invention at the excitation frequency of 1.00 Hz;

[0038] Figure 8 The spectrum diagram of the key nodes of the model of the present invention at the excitation frequency of 1.33 Hz;

[0039] Fig. 9 The spectrum diagram of the key nodes of the model of the present invention at the excitation frequency of 1.67 Hz;

[0040] Fig.10It is the spectrum diagram of the key nodes of the model of the present invention at the excitation frequency of 2.00 Hz. DETAILED DESCRIPTION

[0041] The invention discloses a method and a system for monitoring the acoustic emission of wind-induced vibration noise of a stay cable.

[0042] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In order to make the purpose, technical solution and advantages of the embodiment of the present application clearer, the technical solution in the embodiment of the present application will be described clearly and completely in conjunction with the drawings in the embodiment of the present application. It should be understood that the drawings in the present application are only for the purpose of illustration and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application are as follows: Figure 1 The operations implemented according to some embodiments of the present application are shown. It should be understood that the operations of the flowchart can be implemented in a non-sequential manner, and steps without logical contextual relationships can be reversed in order or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart under the guidance of the content of this application, or remove one or more operations from the flowchart.

[0044] In addition, the described embodiments are only some embodiments of the present application, not all embodiments. The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of the present application.

[0045] like Figure 1 , is a flow chart of a method for monitoring wind-induced vibration noise and acoustic emission of a stay cable provided in an embodiment of the present invention. Further, the method for monitoring wind-induced vibration noise and acoustic emission of a stay cable includes the following steps:

[0046] A cable model is installed in the laboratory. The cable model uses a steel wire rope with a diameter of 5mm and a length of 2.52m, several mass blocks with a diameter of 15mm, an open flower basket, several expansion bolts, a fixed pulley, a steel frame, etc., which are assembled into the cable model in sequence; the acoustic emission monitoring system uses a DS5 acoustic emission acquisition system, which includes several S-2A sensors and DS5-16B full-waveform acoustic emission analyzers and several amplifiers with a gain of 40dB; the external excitation system is an elastic rope, a servo motor, which includes an encoder line, a motor power line, a signal line, a motor plus drive, a power supply, etc.

[0047] The upper end of the cable model is fixed to the ceiling by expansion bolts, and the lower end is fixed to the steel frame on the ground by bolts around the fixed pulley. The tension of the cable model can be adjusted by the open flower basket at the lower end. At the same time, in order to make the cable model more in line with the actual cable, the linear mass of the cable model is increased, and the mass blocks are evenly arranged on the wire rope at a spacing of 2.5 cm along the longitudinal direction. The arrangement position of the RS-2A sensor is determined according to the length L of the cable model. First, multiple monitoring nodes are arranged along the longitudinal monitoring area of ​​the cable model, and the acoustic emission signal of the target monitoring area is obtained through the monitoring nodes. The main frequency and frequency band distribution range of the acoustic emission signal of the cable wind vibration noise are analyzed by fast Fourier transform, including frequency domain analysis and time domain analysis. According to the analyzed acoustic emission signal characteristics (spectral characteristics, time domain characteristics) of the cable wind vibration noise, the peak rate, bandwidth, amplitude, amplitude, duration, RMS, ASL of the acoustic emission signal characteristic parameters of the cable wind vibration noise are obtained, including statistical characteristics and spectral characteristics.

[0048] Since the cable model is a centrally symmetrical structure, the accuracy and reliability of the overall response of the structure are ensured through the previous characteristic analysis. The previous characteristic analysis involves the acoustic emission signal characteristics of the wind-induced vibration noise of the cable at multiple monitoring points at different longitudinal positions of the inclined cable under different external excitation conditions. The selection of five nodes obtained according to the structural analysis can represent the dynamic characteristics of the entire cable.

[0049] Because the five nodes are used as the target monitoring area to construct key monitoring nodes, the research scope selects the lower half of the cable structure for research. The five nodes are arranged at L / 12, L / 6, L / 4, L / 3, and L / 2. These nodes are located in the key response area of ​​the cable structure. Based on statistical characteristics, time domain analysis, and spectrum analysis, they can represent the main dynamic behaviors of the cable in the vibration or stress concentration area. The statistical data of the five key nodes are shown in the attached figure. Figure 7 To Attachment Fig.10 As shown in Table 1:

[0050] Table 1 Peak frequency at various positions of the cable with the same excitation amplitude (kHz)

[0051]

[0052] The surface of the measuring point needs to be cleaned before installation. The sensor is pasted in the pre-designed position and fixed with tape. Vaseline is applied between the sensor and the structure as a coupling agent to ensure full contact between the sensor and the structure. The forced vibration test is carried out by simulating the fluid mass force and wind-induced vibration through a servo motor. An elastic rope is used, one end of which is fixed at the mid-span position of the cable and the other end is fixed to the rotating rod of the motor. The rotation of the rotating rod is converted into harmonic excitation through the elastic rope, thereby exciting the vibration of the corresponding mode of the cable. The external excitation frequency is adjusted by changing the speed of the motor, and the external excitation amplitude is adjusted by changing the length of the rotating rod.

[0053] After debugging the acoustic emission instrument, the environmental noise of the cable model in the static state was collected using the acoustic emission instrument. It was observed that the amplitude of each channel was less than 10mv, indicating that the influence of the environmental noise could be ignored. Then a lead breaking experiment was carried out at L / 2 on the cable model to simulate damage, and the amplitude of each channel was observed. It met the attenuation law, indicating that the acoustic emission monitoring system was normal. If an abnormality occurred, the acoustic emission monitoring system needed to be re-adjusted until it met the requirements.

[0054] The servo motor is selected as the point excitation source for external excitation to simulate the wind-induced vibration of the cable model caused by the flow-mass force. The wind-induced vibration frequency of the cable is roughly between 0.3Hz and 3Hz, and the corresponding wind speed is in the range of 5 to 20m / s. The servo motor is used as the excitation source. By inputting the control signal into the electronic component, the electronic component will adjust the current according to the control signal, thereby accurately controlling the rotation angle and speed of the motor. The speed is converted to frequency by the formula (speed = 60 / frequency). The excitation frequency increases from 0.50Hz in small increments until the test is terminated at a frequency of about 3.50Hz, with a step size of about 0.17Hz. Strong wind may cause the cable to bend, increase tension or increase vibration amplitude. The external excitation amplitude is set to 106cm, 107cm, and 108cm. At each excitation frequency, the acoustic emission data acquisition time will be kept long enough to ensure a steady-state response.

[0055] Based on the key monitoring nodes constructed according to the test results above, the acoustic emission signal characteristics of wind-induced noise of cables at different locations were studied; based on the acoustic emission signals of wind-induced noise, the layout of monitoring nodes, and the characteristics of acoustic emission signals, the laboratory method was extended to in-service cables;

[0056] Experiments are usually conducted using scaled models, which may not fully replicate the structural characteristics and dynamic response of large cable-stayed bridges. The cable-stayed bridge structure on site includes a complete cable system and the bridge deck itself, which is much larger and more complex than the laboratory model, and has certain differences in vibration modes and noise characteristics from the laboratory.

[0057] According to the above test results, the key monitoring nodes are constructed, including: arranging multiple monitoring nodes along the longitudinal monitoring area of ​​the cable model, obtaining the acoustic emission signals of the target monitoring area through the monitoring nodes, and analyzing the acoustic emission characteristic parameters of the acoustic emission signals, such as peak frequency, bandwidth, energy, amplitude, duration, RMS, and ASL, finding that the cable positions L / 2, L / 3, L / 4, L / 6, and L / 12 are still the key monitoring nodes.

[0058] Investigate and understand the cable-stayed bridge and the surrounding environment, and prepare the test equipment and instruments in advance. The main test equipment includes mobile power supply, computer host, display, acoustic emission acquisition card, acoustic emission sensor, preamplifier, pencil, coupling agent and tape, etc. (other auxiliary related equipment such as Figure 5 As shown in, including wind and rain resistant interference wire, magnetic flux sensor, cable tension meter, sheath interface, etc. are all existing technologies, and technical personnel in this field understand their use methods and are proficient in using them, so there is no need to elaborate on them).

[0059] After placing the computer host and monitor on the sidewalk near the cable to be monitored on the cable-stayed bridge, power on the sensor preamplifier and acquisition card to the equipment in turn and set the acquisition parameters.

[0060] The experiment selected 6 channels in the acquisition card, with an acquisition rate of 3MHz and a preamplifier gain of 40dB. Considering the small amplitude of environmental noise, the acquisition range was adjusted to ±200mV.

[0061] Due to the complexity of the in-service cable-stayed cables, the following factors should be considered when selecting monitoring locations on cable-stayed bridges based on the laboratory. For example, the longitudinal and transverse positions of the cable-stayed cables Figure 3 and Figure 4 As shown, the vicinity of the bridge tower and the anchorage area are Figure 5 As shown in the figure, these areas are known to be greatly affected by wind vibration through previous model experiments. First, the parts where the acoustic emission sensors are to be installed should be cleaned, the oxide scale, paint and other debris on the surface of the inclined cable should be removed, and the rough surface should be polished. Considering the interference of the external environment and the high arrangement position of the acoustic emission sensors on the inclined cable, this project uses an aerial work vehicle to arrange the sensors, wrap the acoustic emission sensors around the inclined cable with insulating tape, and apply coupling agent on its surface to ensure good contact between the sensor and the cable.

[0062] After the equipment is powered on, the experiment is carried out. By conducting a lead-breaking experiment on the inclined cable, it is determined whether the lead-breaking signal of the inclined cable conforms to the attenuation law. If it conforms, the equipment is operating normally. If it does not conform, the equipment needs to be checked until it conforms, and then the wind-vibration noise collection test of the inclined cable is started. In this case, the signal characteristics captured by the monitoring of three different inclined cables with cable numbers C1, C7, and C13 in reality are shown in Tables 2 to 4:

[0063] Table 2 Statistics of characteristic parameters of wind-induced noise emission signals of C1 cable-stayed cables

[0064]

[0065] Table 3 Statistics of characteristic parameters of wind-induced noise emission signals of cable No. C7

[0066]

[0067] Table 4 Statistics of characteristic parameters of wind-induced noise emission signals of C13 cable-stayed cables

[0068]

[0069] According to the random forest feature importance selection method, acoustic emission characteristic parameters are selected and correlation analysis is performed to realize the recognition of acoustic emission signals of wind-induced vibration noise of inclined cables, and the corresponding conclusions are summarized as the identification of acoustic emission signals of wind-induced vibration noise of inclined cables. The specific process is as follows:

[0070] The cable wire break signal in the laboratory is mixed with the wind vibration noise signal. Through feature selection, the characteristic parameters that are most helpful for separating the cable damage signal and the wind vibration noise signal are obtained, so as to perform time domain analysis and frequency domain analysis of the wind vibration noise acoustic emission signal. First, the random forest algorithm is used to evaluate the importance of each feature, and then the most important key features are selected. Finally, these selected key features are used to train the classification model and evaluate its performance. This process will determine the parameters that are most suitable for distinguishing the two signals.

[0071] The feature importance results based on the random forest algorithm are as follows Figure 6 As shown, the feature parameter impact rate has the highest importance and is the most critical predictor in the model. This indicates that there is a strong correlation between impact rate and the target variable in the current model. ASL, amplitude, and RMS are also important features in this model and contribute significantly to the prediction of the model. Figure 6 In the lower part of , the importance of the characteristic parameter rise time is 0, indicating that the rise time is not important for distinguishing the cable broken wire signal and the wind vibration noise signal.

[0072] In the decision-making process based on the random forest algorithm, features with higher importance are given priority, and low-importance features are further analyzed as needed to improve the accuracy of feature differentiation. In addition, the importance score does not necessarily reflect the causal relationship of the features, but only their relative contribution to the model's predictive ability.

[0073] By analyzing the acoustic emission signal characteristics collected by real-time monitoring of the cable-stayed structure, the present invention can exclude the wind vibration noise signal part and identify the fatigue or damage signal of the structure. The purpose of the analysis is to detect potential structural problems and provide early warning. Therefore, these acoustic emission signal characteristics can be used to monitor the structural health of the cable-stayed structure, evaluate the actual operating status of the cable-stayed bridge in service, predict potential risks, and guide maintenance and repair work, which can effectively monitor and maintain the safety of the cable-stayed bridge in service and improve its operating efficiency and lifespan.

[0074] The above description is only for illustrating the present invention. It should be understood that the present invention is not limited to the above embodiments, and various variations that conform to the concept of the present invention are within the protection scope of the present invention.

Claims

1. A method for monitoring acoustic emission of wind-induced vibration noise of a cable, characterized in that: The following steps are involved: S1: A non-damaged cable model was selected in the laboratory, wind-induced vibration was simulated by a servo motor, and the acoustic emission signal of the wind-induced vibration noise of the cable was collected by an acoustic emission monitoring system. The acoustic emission signal characteristics of the wind-induced vibration noise of the cable at multiple monitoring points at different longitudinal positions of the cable under different external excitation conditions were analyzed; S2: Based on the analysis results of the acoustic emission signal characteristics of the wind-induced vibration noise of the cables in S1 and the centrally symmetrical structural characteristics of the cable model in S1, a layout of key monitoring nodes is constructed; S3: deploying the acoustic emission monitoring system in S1 and the key monitoring nodes in S2 on the cables of the in-service cable-stayed bridge to collect the acoustic emission signals of the noise of the cables of the in-service cable-stayed bridge; S4: Select the characteristic parameters of the acoustic emission signal in S3 based on the importance selection method of the random forest algorithm, and perform correlation analysis to realize the acoustic emission signal recognition of the wind-induced vibration noise of the inclined cable.

2. The method for monitoring wind-induced noise and acoustic emission of a stay cable according to claim 1 is characterized in that: The method for simulating wind-induced vibration by a servo motor in S1 is as follows: one end of an elastic rope is fixed to the mid-span position of the cable of the cable model, and the other end is fixed to the rotating rod of the servo motor; the rotation of the rotating rod is converted into harmonic excitation by the elastic rope, thereby exciting the vibration of the corresponding mode of the cable, the external simulated excitation frequency is adjusted by changing the rotation speed of the servo motor, and the external simulated excitation amplitude is adjusted by changing the length of the rotating rod. In order to ensure that the experimental conditions can simulate the situations that may occur in the real environment, the vibration frequency of the external simulated excitation amplitude is set in a wider frequency range, gradually increasing from 0.5 Hz to 3.5 Hz.

3. The method for monitoring wind-induced noise and acoustic emission of a stay cable according to claim 1 is characterized in that: The acoustic emission signal characteristic analysis process in S1 specifically includes the following steps: S1-1: collecting the acoustic emission signal of the wind vibration noise of the cable, and performing preprocessing including noise removal and filtering to ensure the quality of the acoustic emission signal; S1-2: Analyze the main frequency and frequency band distribution range of the acoustic emission signal of the cable wind vibration noise through fast Fourier transform, including frequency domain analysis and time domain analysis; S1-3: The acoustic emission signal characteristics of the cable wind-vibration noise analyzed in S1-2 include spectral characteristics and time domain characteristics. The characteristic parameters of the two characteristics include peak frequency, bandwidth, amplitude, amplitude, duration, RMS, and ASL. The global spectral characteristics of the acoustic emission signal of the cable wind-vibration noise are obtained, including statistical characteristics and spectral characteristics.

4. The method for monitoring wind-induced noise and acoustic emission of a stay cable according to claim 1 is characterized in that: The construction of the key monitoring node layout in S2 includes selecting the L / 2, L / 3, L / 4, L / 6, and L / 12 positions in the lower half of the cable model upward in sequence as key monitoring nodes, where L is the length of the cable.

5. The method for monitoring wind-induced noise and acoustic emission of a stay cable according to claim 1 is characterized in that: The S4 specifically comprises the following steps: S4-1: Mix the cable wire breakage signal and wind vibration noise signal in the laboratory, and collect the characteristic parameters of the mixed acoustic emission signal including peak frequency, bandwidth, amplitude, amplitude, duration, RMS, and ASL; S4-2: Evaluate the importance of each feature parameter based on the random forest algorithm and select important key feature parameters; S4-3: Based on the random forest algorithm, the classification model is trained using the key characteristic parameters in S4-2 to separate the damage acoustic emission signal of the cable from the wind vibration noise acoustic emission signal of the cable.

6. The method for monitoring wind-induced noise and acoustic emission of a stay cable according to claim 5 is characterized in that: The important key characteristic parameters in S4-2 include impact rate, ASL, amplitude, and RMS.

7. The acoustic emission monitoring system of the method for monitoring the acoustic emission of wind-induced noise of the stay cable according to claim 1 is characterized in that: include: The acoustic emission sensor is in direct contact with the bridge cable, and is used to collect the acoustic emission signal emitted by the detected cable and transmit the acoustic signal to the acoustic emission acquisition card; The preamplifier is used to amplify the intensity of the acoustic signal transmitted over a long distance several times and output the analog signal to the acoustic emission sensor, and adopts a single-ended input method; Acoustic emission acquisition card, used to collect acoustic signals from acoustic emission sensors; The computer host is used to process, record and analyze the acoustic emission signals collected by the acoustic emission acquisition card.

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