A comprehensive interface damage testing system and method based on 3D laser vibration measurement

Abstract

This invention discloses a comprehensive interface damage testing system and method based on 3D laser vibrometrics. The system includes: a laser ultrasonic generator or automatic hammer as an excitation device, a 3D laser vibrometer as a sensing device, and data acquisition and analysis equipment. The laser ultrasonic generator and automatic hammer are used to generate high-quality, repetitive pulse excitation signals. The 3D laser vibrometer includes multiple 2D scanning laser vibrometer lenses positioned at different locations to measure the generated stress waves and acquire 3D surface wave data. The data acquisition and analysis equipment simultaneously performs multichannel surface wave analysis based on Rayleigh and Love waves based on the acquired 3D surface wave data to identify the damaged area. This invention fully utilizes the increased data dimensionality of multichannel surface waves, enabling simultaneous MALA, MASW, 3D vibration modal testing, and impact response testing with a single data acquisition, achieving efficient integration of multiple non-contact testing technologies and improving identification accuracy.

Description

Technical Field

[0001] This invention relates to the field of engineering structure damage detection technology, and in particular to a comprehensive interface damage testing system and method based on 3D laser vibration measurement. Background Technology

[0002] Interfacial bond damage testing in steel-concrete composite structures and FRP / steel plate reinforced concrete structures is a major challenge and research hotspot in the field of civil engineering damage detection. This is primarily because such interfacial damage is generally located at the interface, is non-contact, and is highly concealed. Due to the risks of reduced load-bearing capacity and induced corrosion, efficient detection of the interfacial bond state is of significant engineering importance. However, this type of damage is generally a hidden defect, and traditional detection techniques suffer from low accuracy and efficiency. Furthermore, the manual labor involved in installing and dismantling contact sensors is substantial, making it difficult to meet the increasingly demanding requirements of practical engineering projects.

[0003] Existing interface damage testing methods are generally developed based on damage testing of concrete and steel structures, such as the impact echo method, impact acoustic vibration method, impact response method, ultrasonic testing, and ultrasonic CT. The signal analysis of the above methods all assume that the material composition of the component under test is a single material, and in theoretical analysis, it is assumed to be a homogeneous material.

[0004] Unlike concrete and steel structures, composite structures, such as those composed of steel and concrete, and FRP (carbon fiber reinforced plastic) fabric / plates and concrete, consist of two different materials. Furthermore, steel plates and FRP fabric / plates are significantly thinner than concrete. Due to the significant differences in the elastic modulus, density, and Poisson's ratio of these materials, their vibration characteristics and stress wave propagation velocities differ considerably. This leads to incoordination in vibration deformation and interface reflection of stress waves due to impedance mismatch at the interface. Therefore, existing testing methods based on the assumption of a single material are insufficient for accurate testing of interface damage in engineering structures.

[0005] A compromise solution in existing research is to use traditional impact-echo methods, impact-acoustic methods, impact-response methods, and ultrasonic testing equipment to collect relevant data. Then, the signal attenuation characteristics, amplitude, and frequency differences are compared to qualitatively determine the presence or absence of interface damage. However, these testing methods are only suitable for detecting large-area interface defects; they are ineffective for detecting smaller defects. Furthermore, damage assessment in non-destructive testing heavily relies on the engineering experience of the testing personnel, making misjudgments possible.

[0006] In recent years, testing techniques based on surface waves and multichannel surface waves have been widely adopted, and Doppler laser vibrometers have been extensively used in the testing of stress waves and high-frequency vibrations. However, research on multichannel surface wave methods based on non-contact vibration measurement techniques is relatively limited. This is because conventional Doppler laser vibrometers can only test stress waves perpendicular to the steel plate surface—Rayleigh waves—and cannot test stress waves parallel to the steel plate surface—Love waves. Existing research has shown that Love waves have a higher signal-to-noise ratio than Rayleigh waves; therefore, establishing a testing technique based on non-contact measurement of Love waves has broad engineering application prospects for improving the accuracy of interface damage identification. Summary of the Invention

[0007] To address the aforementioned problems, the present invention aims to provide a comprehensive interface damage testing system and method based on 3D laser vibration measurement. This system integrates multichannel surface wave analysis based on Love and Rayleigh waves, 3D modal scanning, and non-contact impact-response testing technologies. It conducts data acquisition and damage assessment in the longitudinal direction (for determining defect length) and the transverse direction (for determining defect width), significantly improving the accuracy and efficiency of interface damage identification.

[0008] To address the aforementioned technical problems, embodiments of the present invention provide the following solutions:

[0009] On the one hand, a comprehensive interface damage testing system based on 3D laser vibration measurement is provided, including: a laser ultrasonic generator or automatic force hammer as an excitation device, a 3D laser vibration meter as a sensing device, and data acquisition and analysis equipment;

[0010] The laser ultrasonic generator is used to emit laser pulse signals, thereby forming a high-quality, repeatable pulse excitation signal on the surface of the composite structure to be tested; the automatic hammer is used to strike the surface of the composite structure to generate a high-quality, repeatable pulse excitation signal; the 3D laser vibrometer includes multiple 2D scanning laser vibrometer lenses set in different positions, used to measure the stress waves generated on the surface to be tested and collect 3D surface wave data; the data acquisition and analysis equipment simultaneously performs multichannel surface wave analysis based on Rayleigh waves and Love waves based on the collected 3D surface wave data, and identifies the damage area in both longitudinal and transverse dimensions.

[0011] Preferably, based on the different vibration modes at the interface bonding integrity location and the interface peeling location, the 3D laser vibrometer is also used to perform vibration mode scanning tests on the surface to be tested of the composite structure, so as to realize the verification of the damaged area and the determination of the damaged area, and avoid misjudgment by a single method.

[0012] Preferably, the system further includes a high-frequency accelerometer, which is attached to the surface to be tested of the combined structure and is used to verify the test data of the 3D laser vibrometer.

[0013] Preferably, the laser ultrasound generator is connected to a controller, which controls the laser ultrasound generator to trigger laser pulse signals of different frequencies and amplitudes, thereby forming high-quality, repeatable pulse excitation signals of different frequencies and amplitudes on the surface to be tested of the combined structure.

[0014] Preferably, the automatic hammer is connected to a controller, which controls the hammer's striking force amplitude, striking angle, and striking frequency to generate a high-quality, repetitive pulse excitation signal.

[0015] Preferably, both the laser ultrasonic generator and the 3D laser vibrometer are supported by a tripod, with a bracket fixed at the top of the tripod parallel to the surface to be tested. The laser ultrasonic generator and the 3D laser vibrometer are fixed above the surface to be tested by the bracket.

[0016] Preferably, the 3D laser vibration meter includes three 2D scanning laser vibration lenses. The three 2D scanning laser vibration lenses are fixed on the same bracket at uniform intervals. The 2D scanning laser vibration lens in the middle is perpendicular to the surface to be tested, and the 2D scanning laser vibration lenses on both sides are tilted inward at symmetrical angles.

[0017] Preferably, the surface to be tested is provided with a matrix of measuring points, and the 3D laser vibrometer performs scanning measurements on each measuring point in the matrix.

[0018] Preferably, the single-channel data of each measuring point in the measuring point matrix can be used for impact-response testing, and the data acquisition and analysis equipment realizes non-contact impact-response testing by analyzing the amplitude, energy and frequency of the single-channel data in the multi-channel surface wave.

[0019] On the one hand, a testing method based on the aforementioned comprehensive interface damage testing system is provided, comprising the following steps:

[0020] Set up a test network for the 3D laser vibrometer, wherein the test network is a matrix of measurement points on the surface to be tested;

[0021] The computer, acting as a controller, controls the amplitude of the impact force, the impact angle, and the impact frequency of the automatic hammer, or controls the laser ultrasonic generator to trigger laser pulse signals of different frequencies and amplitudes to generate high-quality, repetitive pulse excitation signals.

[0022] The waveform of the generated pulse excitation signal is examined using an oscilloscope, and the waveform is verified for abnormality using a contact-type high-frequency accelerometer.

[0023] If the waveform is abnormal, check the equipment installation and start the measurement again; if the waveform is normal, apply a pulse excitation signal for detection.

[0024] Acquire test signals from a scanning 3D laser vibrometer and simultaneously save the automatic hammer voltage response signal, laser pulse excitation signal, 3D laser vibrometer test signal, and number of tests;

[0025] Determine if the number of tests meets the requirements for longitudinal and transverse multi-channel data analysis; if not, continue collecting test data; if so, perform decoupling analysis of horizontal Love wave vibration data and vertical Rayleigh wave vibration data, as well as impact-response analysis, to achieve interface damage detection.

[0026] Determine whether all channel tests have been completed; after all channel tests are completed, perform 3D scanning vibration modal testing and analysis to further determine the damage area;

[0027] Save the test data and analysis results to complete the test.

[0028] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:

[0029] This invention is based on 3D laser vibration measurement technology, which carries out longitudinal and transverse data acquisition respectively. At the same time, it utilizes Rayleigh wave-based multichannel surface wave analysis method and Love wave-based multichannel surface wave analysis method to achieve dimensional improvement in both test data and test direction, thereby significantly improving the accuracy of interface damage identification.

[0030] This invention fully leverages the increased data dimensionality of multichannel surface waves, enabling simultaneous MALA, MASW, 3D vibration modal testing, and shock-response testing with a single data acquisition. Utilizing 3D surface wave data, this invention simultaneously conducts non-contact multichannel surface wave testing based on Rayleigh and Love waves, non-contact 3D vibration modal scanning testing, and analyzes the amplitude, energy, and frequency of single-channel data from multichannel surface waves to achieve non-contact shock response analysis, thus realizing the efficient integration of multiple non-contact testing technologies. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of a comprehensive interface damage testing system based on 3D laser vibration measurement;

[0033] Figure 2 This is a schematic diagram of the test system structure based on a laser ultrasonic generator provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the test point layout of the laser ultrasonic generator-based test system provided in an embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of the structure of a test system based on an automatic force hammer drive provided in an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the test point layout of the test system based on automatic force hammer drive provided in an embodiment of the present invention;

[0037] Figure 6 This is a schematic diagram of the surface wave time history curves of Rayleigh waves and Love waves provided in an embodiment of the present invention;

[0038] Figure 7 This is a schematic diagram of the surface wave dispersion curves of Rayleigh waves and Love waves provided in an embodiment of the present invention;

[0039] Figure 8 This is a schematic diagram of the 3D vibration mode of the interface damage site of the combined structure provided in the embodiment of the present invention;

[0040] Figure 9 This is a connection diagram of the laser ultrasonic generator provided in an embodiment of the present invention;

[0041] Figure 10 This is a connection diagram of the automatic hammer provided in an embodiment of the present invention;

[0042] Figure 11 This is a connection diagram of the high-frequency acceleration sensor provided in an embodiment of the present invention;

[0043] Figure 12 This is a flowchart of the testing method provided in the embodiments of the present invention.

[0044] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, those skilled in the art can adjust or modify these devices and environments, and such adjustments or modifications are still included in the protection scope of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Embodiments of the present invention provide a comprehensive interface damage testing system based on 3D laser vibration measurement. For example... Figures 1-5 As shown, where, Figure 1 This is a schematic diagram of the interface damage comprehensive testing system based on 3D laser vibration measurement provided in an embodiment of the present invention. Figure 2 and Figure 3 This is a schematic diagram of the structure and measurement point layout of a test system based on a laser ultrasonic generator. Figure 4 and Figure 5 This is a schematic diagram of the structure and measuring point layout of a test system based on an automatic force hammer.

[0047] In this embodiment of the invention, the testing system includes: a laser ultrasonic generator 11 or an automatic force hammer 12 as an excitation device, a 3D laser vibration meter 2 as a sensing device, and a data acquisition and analysis device 3.

[0048] A laser ultrasonic generator 11 is used to emit laser pulse signals, thereby forming a high-quality, repeatable pulse excitation signal on the surface of the composite structure to be tested; an automatic hammer 12 is used to strike the surface of the composite structure to generate a high-quality, repeatable pulse excitation signal; a 3D laser vibrometer 2 includes multiple 2D scanning laser vibrometer lenses (e.g., ...) positioned at different locations. Figure 1 The first laser vibration measuring lens 21, the second laser vibration measuring lens 22, and the third laser vibration measuring lens 23 are used to measure the stress waves generated on the surface to be tested and collect 3D surface wave data. The data acquisition and analysis device 3 simultaneously performs multichannel surface wave analysis based on Rayleigh waves and Love waves based on the collected 3D surface wave data to identify the damage area in both longitudinal and transverse dimensions.

[0049] The testing mechanisms of Rayleigh waves and Love waves are as follows: Figure 6 and Figure 7 As shown. Figure 6 In the figure, (a) represents the total amplitude of the surface wave, and (b) and (c) represent the time history curves of the Love wave component in the X direction and the Rayleigh wave component in the Y direction, respectively. Figure 7 In the diagram, (a) and (b) represent the dispersion curves of Love waves in the absence of defects and with defects, and (c) and (d) represent the dispersion curves of Rayleigh waves in the absence of defects and with defects.

[0050] Existing technologies can only test stress waves perpendicular to the steel plate surface—Rayleigh waves—while Love waves have not been studied. However, Love waves have a higher signal-to-noise ratio than Rayleigh waves and have advantages such as simple dispersion characteristics and low dependence on dispersion curve inversion results. This invention is based on 3D laser vibration measurement technology, which conducts longitudinal and transverse data acquisition separately. At the same time, it utilizes the Multichannel Analysis of Surface Waves (MASW) based on Rayleigh waves and the Multichannel Analysis of Love Waves (MALA) based on Love waves to achieve dimensional improvements in both test data and test direction, thereby significantly improving the accuracy of interface damage identification.

[0051] Furthermore, based on the different vibration modes at the interface bonding sites and interface peeling sites, the present invention uses a 3D laser vibration meter 2 to perform vibration mode scanning tests on the surface to be tested of the composite structure, thereby realizing the verification of the damaged area and the determination of the damaged area, avoiding misjudgment by a single method.

[0052] Figure 8 This is a schematic diagram of the 3D vibration mode of the interface damage site of the combined structure provided in the embodiment of the present invention. Figure 8 (a) is a cross-sectional view of the combined structure, and (b), (c), and (d) are schematic diagrams of the first-order vibration mode, second-order vibration mode, and third-order vibration mode, respectively. This invention is based on... Figure 8 The mechanism shown can be further verified by using a 3D laser vibration meter to perform vibration mode scanning tests on the surface of steel plates or FRPs, and the damage area can be quickly determined.

[0053] Furthermore, such as Figure 1 As shown, the system also includes a high-frequency acceleration sensor 4, which is attached to the surface to be tested of the combined structure and is used to verify the accuracy of the test data of the 3D laser vibration meter 2.

[0054] In this embodiment of the invention, the connection diagrams of the laser ultrasonic generator 11, the automatic hammer 12, and the high-frequency accelerometer 4 are shown below. Figure 9 , Figure 10 , Figure 11As shown. The laser ultrasonic generator 11 is connected to a controller (not shown in the figure). The controller controls the laser ultrasonic generator 11 to trigger laser pulse signals of different frequencies and amplitudes, thereby forming high-quality, repeatable pulse excitation signals of different frequencies and amplitudes on the surface to be tested of the combined structure. The automatic hammer 12 is connected to the controller 7. The controller 7 controls the impact force amplitude, impact angle, and impact frequency of the automatic hammer to generate high-quality, repeatable pulse excitation signals. The laser ultrasonic generator 11, the automatic hammer 12, and the high-frequency accelerometer 4 are all connected to the data acquisition and analysis device 3 via a BNC interface.

[0055] As a specific embodiment of the present invention, such as Figure 2 As shown, both the laser ultrasonic generator 11 and the 3D laser vibrometer are supported by the stand 5. The top of the stand 5 is fixed with a bracket 6 parallel to the surface to be tested. The laser ultrasonic generator 11 and the 3D laser vibrometer are fixed above the surface to be tested by the bracket 6.

[0056] The 3D laser vibration meter includes three 2D scanning laser vibration lenses. The three 2D scanning laser vibration lenses are fixed on the same bracket 6 at even intervals. The 2D scanning laser vibration lens in the middle is perpendicular to the surface to be tested, and the 2D scanning laser vibration lenses on both sides are tilted inward at symmetrical angles.

[0057] The above is merely a preferred embodiment of the present invention and does not constitute a limitation thereof. Depending on actual application requirements, the present invention can also be configured with different numbers of laser vibrometer lenses and different layouts to obtain 3D surface wave data, which will not be elaborated further here.

[0058] Furthermore, such as Figure 3 and Figure 5 As shown, a measurement point matrix is ​​set on the surface to be tested, and a 3D laser vibrometer performs scanning measurements on each measurement point (1, 2, ..., 48) in the measurement point matrix. The single-channel data of each measurement point in the measurement point matrix can be used for impact-response testing. The data acquisition and analysis equipment realizes non-contact impact-response testing by analyzing the amplitude, energy, and frequency of the single-channel data in the multi-channel surface wave.

[0059] This invention fully utilizes the data dimension enhancement advantage of multi-channel surface waves, enabling simultaneous MALA, MASW, 3D vibration modal testing, and shock-response testing with a single data acquisition, achieving efficient integration of multiple non-contact testing technologies.

[0060] This invention utilizes 3D surface wave data to simultaneously conduct non-contact multichannel surface wave testing based on Rayleigh and Love waves, non-contact 3D vibration modal scanning testing, and analysis of the amplitude, energy, and frequency of single-channel data in multichannel surface waves to achieve non-contact impact response analysis, significantly improving identification efficiency and accuracy.

[0061] Accordingly, embodiments of the present invention also provide a testing method based on the above-described comprehensive interface damage testing system, such as... Figure 12 As shown, the method includes the following steps:

[0062] Set up a test network for the 3D laser vibrometer, wherein the test network is a matrix of measurement points on the surface to be tested;

[0063] The computer, acting as a controller, controls the amplitude of the impact force, the impact angle, and the impact frequency of the automatic hammer, or controls the laser ultrasonic generator to trigger laser pulse signals of different frequencies and amplitudes to generate high-quality, repetitive pulse excitation signals.

[0064] The waveform of the generated pulse excitation signal is examined using an oscilloscope, and the waveform is verified for abnormality using a contact-type high-frequency accelerometer.

[0065] If the waveform is abnormal, check the equipment installation and start the measurement again; if the waveform is normal, apply a pulse excitation signal for detection.

[0066] Acquire test signals from a scanning 3D laser vibrometer and simultaneously save the automatic hammer voltage response signal, laser pulse excitation signal, 3D laser vibrometer test signal, and number of tests;

[0067] Determine if the number of tests meets the requirements for longitudinal and transverse multi-channel data analysis; if not, continue collecting test data; if so, perform decoupling analysis of horizontal Love wave vibration data and vertical Rayleigh wave vibration data, as well as impact-response analysis, to achieve interface damage detection.

[0068] Determine whether all channel tests have been completed; after all channel tests are completed, perform 3D scanning vibration modal testing and analysis to further determine the damage area;

[0069] Save the test data and analysis results to complete the test.

[0070] Compared with existing laser Doppler vibration measurement technology, the 3D vibration measurement technology provided by this invention can simultaneously acquire high-frequency stress waves and vibration data of the steel plate surface, and has the following technical advantages:

[0071] a) It can simultaneously perform multi-channel surface wave testing based on Rayleigh waves and Love waves. By leveraging the high signal-to-noise ratio of Love waves, the signal quality of multi-channel surface waves can be improved, thereby enhancing the testing accuracy of interface damage.

[0072] b) It can more realistically measure the vibration-assisted / vibration energy at the measuring point, enabling comparison of energy in the test area and providing real and reliable data.

[0073] c) It can realize 3D non-contact testing. With the help of a laser ultrasonic generator as the excitation source, it can realize a completely non-contact process of non-contact excitation and perception for interface damage identification.

[0074] d) Due to the debonding at the interface, the steel plate and concrete lose their bond, and the steel plate at the top of the defect loses the constraint of the bottom concrete, resulting in significant differences in the vibration modes of the steel plate. Therefore, vibration mode testing can be carried out using a 3D scanning laser vibrometer to further determine the damage pattern and improve testing accuracy.

[0075] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0076] The use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0077] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0078] It is understood that the meanings of “on”, “above” and “above” in this disclosure should be interpreted in the broadest sense, such that “on” means not only “directly on” something, but also includes something with an intermediary feature or layer, and that “above” or “above” means not only “on” something, but also includes something “above” or “above” without an intermediary feature or layer.

[0079] Furthermore, spatially related terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein for convenience to describe the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. Spatially related terms are intended to cover different orientations in the use or operation of the device other than those depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially related descriptive terms used herein can be interpreted similarly.

[0080] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0081] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A comprehensive interface damage testing system based on 3D laser vibration measurement, characterized in that, include: Laser ultrasonic generators or automatic force hammers as excitation devices, 3D laser vibration meters as sensing devices, and data acquisition and analysis equipment; The laser ultrasonic generator is used to emit laser pulse signals, thereby forming repetitive pulse excitation signals on the surface of the composite structure to be tested; the automatic hammer is used to strike the surface of the composite structure to be tested to generate repetitive pulse excitation signals; the 3D laser vibrometer includes multiple 2D scanning laser vibrometer lenses set in different positions, used to measure the stress waves generated on the surface to be tested and collect 3D surface wave data; the data acquisition and analysis equipment simultaneously performs multichannel surface wave analysis based on Rayleigh waves and Love waves based on the collected 3D surface wave data, and identifies the damage area in both longitudinal and transverse dimensions; The composite structure is a steel-concrete composite structure. Based on the different vibration modes at the interface bonding sites and interface peeling sites, the 3D laser vibration meter is also used to perform vibration mode scanning tests on the surface to be tested of the composite structure, so as to realize the verification of the damaged area and the determination of the damaged area, avoiding misjudgment by a single method.

2. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 1, characterized in that, The system also includes a high-frequency accelerometer, which is attached to the surface to be tested of the combined structure and is used to verify the test data of the 3D laser vibrometer.

3. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 1, characterized in that, The laser ultrasonic generator is connected to a controller, which controls the laser ultrasonic generator to trigger laser pulse signals of different frequencies and amplitudes, thereby forming repetitive pulse excitation signals of different frequencies and amplitudes on the surface to be tested of the combined structure.

4. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 1, characterized in that, The automatic hammer is connected to a controller, which controls the hammer's striking force amplitude, striking angle, and striking frequency to generate a repetitive pulse excitation signal.

5. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 1, characterized in that, Both the laser ultrasonic generator and the 3D laser vibrometer are supported by a tripod. The top of the tripod is fixed with a bracket parallel to the surface to be tested. The laser ultrasonic generator and the 3D laser vibrometer are fixed above the surface to be tested by the bracket.

6. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 5, characterized in that, The 3D laser vibration meter includes three 2D scanning laser vibration lenses. The three 2D scanning laser vibration lenses are fixed on the same bracket at even intervals. The 2D scanning laser vibration lens in the middle is perpendicular to the surface to be tested, and the 2D scanning laser vibration lenses on both sides are tilted inward at symmetrical angles.

7. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 1, characterized in that, The surface to be tested is provided with a matrix of measuring points, and the 3D laser vibrometer performs scanning measurements on each measuring point in the matrix.

8. The comprehensive interface damage testing system based on 3D laser vibration measurement according to claim 7, characterized in that, The single-channel data of each measuring point in the measuring point matrix can be used for impact-response testing. The data acquisition and analysis equipment realizes non-contact impact-response testing by analyzing the amplitude, energy and frequency of single-channel data in multi-channel surface waves.

9. A test method for a comprehensive interface damage testing system based on 3D laser vibration measurement according to any one of claims 1 to 8, characterized in that, Includes the following steps: Set up a test network for the 3D laser vibrometer, wherein the test network is a matrix of measurement points on the surface to be tested; The computer, acting as a controller, controls the amplitude of the impact force, the impact angle, and the impact frequency of the automatic hammer, or controls the laser ultrasonic generator to trigger laser pulse signals of different frequencies and amplitudes to generate repetitive pulse excitation signals. The waveform of the generated pulse excitation signal is examined using an oscilloscope, and the waveform is verified for abnormality using a contact-type high-frequency accelerometer. If the waveform is abnormal, check the equipment installation and start the measurement again; if the waveform is normal, apply a pulse excitation signal for detection. Acquire test signals from a scanning 3D laser vibrometer and simultaneously save the automatic hammer voltage response signal, laser pulse excitation signal, 3D laser vibrometer test signal, and number of tests; Determine if the number of tests meets the requirements for longitudinal and transverse multi-channel data analysis; if not, continue collecting test data; if so, perform decoupling analysis of horizontal Love wave vibration data and vertical Rayleigh wave vibration data, as well as impact-response analysis, to achieve interface damage detection. Determine whether all channel tests have been completed; after all channel tests are completed, perform 3D scanning vibration modal testing and analysis to further determine the damage area; Save the test data and analysis results to complete the test.

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