Zero-order horizontal shear wave regulation and control method and device and application of zero-order horizontal shear wave regulation and control device

Abstract

The invention provides a zero-order horizontal shear wave regulation and control method and device and application thereof, and relates to the technical field of metamaterials, and the method comprises the steps: carrying out the unit cell division of a single meta-structure element and a plate structure based on an anti-resonance principle, and carrying out the equivalent mass construction of divided unit cells, and forming a spring mass system; simple harmonic excitation force is applied to the spring mass system based on the Newton's law of motion, a mass motion control equation is established, the mass motion control equation is solved through an anti-resonance mechanism, and an anti-resonance geometric configuration is obtained; deducing the anti-resonance geometric configuration in combination with a cylinder approximation method and preset anti-resonance boundary conditions according to shear deformation characteristics of zero-order horizontal shear waves to obtain a superstructure primitive geometric parameter scheme; and regulating and controlling the propagation of the zero-order horizontal shear wave through the metasurface elements in different arrangement modes based on the metasurface elements with the optimal size in the metasurface element geometric parameter scheme. According to the method, the problem that the zero-order horizontal shear wave cannot be accurately and losslessly effectively controlled is solved.

Description

Technical Field

[0001] This invention relates to the field of metamaterials technology, and more specifically, to a method, apparatus, and application for controlling zero-order horizontal shear waves. Background Technology

[0002] Among existing metamaterial technologies, for plate and shell structures, the zero-order horizontal shear wave (SHO wave) is considered one of the most promising ideal guided wave modes for rapid detection and health monitoring of large structures due to its unique property of being completely non-dispersive. In engineering applications, due to the complexity of the object being detected, guided waves not only generate reflected echoes when interacting with defects, but also experience complex scattering and mode conversion effects caused by non-defect scatterers in structural components, significantly reducing the signal-to-noise ratio of the detection signal. Therefore, concentrating guided wave energy and suppressing complex scattering by scatterers requires controlling guided wave propagation. Controlling wave propagation can be understood as changing the transmission path or mode of wave energy to achieve unusual wave phenomena. Metamaterials, as artificial periodic structures, possess flexible unit design, break through the wave response limits of traditional materials, and offer rich wave control characteristics, thus being considered an effective means of controlling wave propagation. Currently, metamaterials used for controlling zero-order horizontal shear waves involve drilling, slotting, and other destructive processes in the components themselves, leading to the problem of not being able to accurately and non-destructively control zero-order horizontal shear waves.

[0003] Therefore, there is an urgent need for a method, device and application for controlling zero-order horizontal shear waves, which would solve the problem of not being able to control zero-order horizontal shear waves accurately and without damage. Summary of the Invention

[0004] The purpose of this invention is to provide a method, apparatus, and application for controlling zero-order horizontal shear waves, in order to improve the aforementioned problems. To achieve the above objective, the technical solution adopted by this invention is as follows: Firstly, this application provides a method for controlling zero-order horizontal shear waves, comprising: Obtain individual superstructure primitives and plate structures.

[0005] Based on the principle of anti-resonance, the individual superstructure and the plate structure are divided into unit cells. By constructing equivalent mass from the divided unit cells, a spring mass system is formed. Based on Newton's laws of motion, a simple harmonic excitation force is applied to the spring-mass system, and a mass motion control equation is established. The mass motion control equation is then solved through an anti-resonance mechanism to obtain an anti-resonance geometric configuration. Based on the shear deformation characteristics of the zero-order horizontal shear wave, the anti-resonance geometric configuration is derived by combining the cylindrical approximation method and the preset anti-resonance boundary conditions, and the superstructure basic geometric parameter scheme is obtained. Based on the optimal size of the superstructure in the aforementioned superstructure geometric parameter scheme, the propagation of the zero-order horizontal shear wave is controlled by superstructures arranged in different ways.

[0006] Secondly, this application also provides a control device for a zero-order horizontal shear wave, comprising: The acquisition module is used to acquire individual meta-elemental units and plate structures; The partitioning module is used to partition the individual superstructure and the plate structure into unit cells based on the anti-resonance principle, and to form a spring mass system by constructing equivalent mass from the partitioned unit cells. A module is established to apply a simple harmonic excitation force to the spring-mass system based on Newton's laws of motion, establish the mass motion control equation, and solve the mass motion control equation through an anti-resonance mechanism to obtain the anti-resonance geometric configuration. The derivation module is used to derive the anti-resonance geometric configuration based on the shear deformation characteristics of the zero-order horizontal shear wave, combined with the cylindrical approximation method and preset anti-resonance boundary conditions, to obtain the superstructure basic geometric parameter scheme. The control module is used to control the propagation of the zero-order horizontal shear wave by using superstructures with different arrangements, based on the optimal size of the superstructure in the geometric parameter scheme.

[0007] Thirdly, this application also provides a method for applying zero-order horizontal shear waves, including: Based on the geometric parameter scheme of the meta-element and the shape of the structure plate to be tested, meta-elements with different arrangements are set up and reserved intervals are reserved to form a waveguide, thus obtaining a waveguide structure; The waveguide structure is arranged along a preset detection target to guide the zero-order horizontal shear wave to propagate along a preset path and determine the propagation direction. An excitation transducer is installed at the beginning of the waveguide, and a receiving transducer is installed at the end. Based on the propagation direction, the zero-order horizontal shear wave is emitted by the excitation transducer for non-destructive testing. When the zero-order horizontal shear wave encounters the defect being tested, it generates a reflected wave or a transmitted wave attenuation. The receiving transducer collects the reflected wave or transmitted wave signal to obtain the defect detection result.

[0008] The beneficial effects of this invention are as follows: This invention utilizes the anti-resonance principle to divide the metamaterial and plate structure into unit cells, and constructs a spring-mass system using equivalent mass. Based on this system, the anti-resonance principle is used to effectively block zero-order horizontal shear waves. Furthermore, by combining Newton's laws of motion and the anti-resonance mechanism, the anti-resonance geometric configuration is obtained, thereby accurately determining the geometric parameters of the metamaterial and improving the design accuracy of the metamaterial. Further, based on the shear deformation characteristics of the zero-order horizontal shear wave, the anti-resonance geometric configuration is derived using the cylindrical approximation method and preset anti-resonance boundary conditions, resulting in a metamaterial geometric parameter scheme. This scheme enables the metamaterial to exhibit excellent mechanical properties at specific frequencies. Moreover, the propagation of the zero-order horizontal shear wave is controlled by different arrangements of the metamaterials within the geometric parameter scheme, enabling flexible control of the wave propagation characteristics. In summary, this invention solves the problem of the inability to accurately and non-destructively control zero-order horizontal shear waves.

[0009] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the method for controlling the zero-order horizontal shear wave as described in an embodiment of the present invention; Figure 2 The simulation results show the effect of the superstructure spacing and height on wave transmittance in the embodiments of the present invention. Figure 3 This is for the calculation of the superstructure bandwidth designed at 50kHz in the embodiments of the present invention; Figure 4 This is a simulation of the meta-element wave isolation and waveguide at 50kHz as described in the embodiments of the present invention; Figure 5 This is the finite element calculation model for the super-element-assisted oblique crack detection simulation described in this embodiment of the invention; Figure 6 This describes the relationship between the amplitude of the reflected echo and the angle of the oblique crack, as illustrated in this embodiment of the invention. Figure 7This is the experimental model used in the experimental verification of super-element-assisted oblique crack detection in the embodiments of the present invention; Figure 8 This refers to the signals measured at different frequencies in the absence of a superstructure in the experimental verification of superstructure-assisted oblique crack detection described in this embodiment of the invention. Figure 9 This is the signal in the super-element-assisted oblique crack detection described in the embodiments of the present invention when a super-element is present; Figure 10 This invention provides an experimental model for verifying the expansion of the zero-order horizontal shear wave detection range using the metastructural primitives described in the embodiments of the present invention. Figure 11 The experimental verification in this embodiment of the invention is to expand the detection range of the zero-order horizontal shear wave by the metastructural primitive. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0013] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0014] Example 1: This embodiment provides a method for controlling zero-order horizontal shear waves.

[0015] See Figure 1 The figure shows that the method includes steps S1 to S5, including: S1: Obtain a single meta-element and plate structure; In this step, the meta-elemental structure is a cuboid, which is arranged on the surface of the plate structure to block the propagation of zero-order horizontal shear waves.

[0016] S2: Based on the principle of anti-resonance, the individual superstructure and the plate structure are divided into unit cells. By constructing equivalent mass of the divided unit cells, a spring mass system is formed. To clarify the specific method for obtaining the spring mass system, step S2 includes S21 to S23, specifically: S21: Based on the anti-resonance principle, the individual superstructure and the plate structure are divided into unit cells to obtain a single unit cell; In this step, the superstructure and the plate structure are theoretically analyzed based on the anti-resonance principle. Based on the theoretical analysis results, the superstructure and the plate structure are divided to obtain a single unit cell, which includes an upper superstructure and three identical lower plates.

[0017] The lower plate includes a first plate, a second plate, and a third plate. The first plate represents the incident wave, the third plate represents the wave transmission region, and the second plate represents the region directly below the corresponding meta-element.

[0018] S22: Perform equivalent mass modeling on the unit cells respectively to obtain the equivalent mass of the superstructure and the equivalent mass of the plate structure; In this step, the unit cells are interconnected by spring units.

[0019] S23: Based on the connection stiffness characteristics of the plate structure and the superstructure, a harmonic force is applied to the equivalent mass of the superstructure and the equivalent mass of the plate structure to simulate an incident zero-order horizontal shear wave, forming a spring-mass system.

[0020] In this step, the equivalent mass of the superstructure is The equivalent mass of the plate structure is , and By assessing the equivalent mass of the plate structure A harmonic force is applied to simulate an incident zero-order horizontal shear wave, forming a spring-mass system.

[0021] S3: Apply a simple harmonic excitation force to the spring-mass system based on Newton's laws of motion, establish the mass motion control equation, and solve the mass motion control equation through the anti-resonance mechanism to obtain the anti-resonance geometric configuration; This step is used to accurately determine the geometric parameters of metamaterial building blocks, thereby improving the design accuracy of metamaterials.

[0022] To clarify the specific method for obtaining the anti-resonance geometry, step S3 includes S31 to S34, specifically: S31: Model the spring-mass system based on Newton's laws of motion, and perform mass element displacement on the equivalent mass of the plate structure in the spring-mass system through simple harmonic excitation force to obtain the mass motion control equation; In this step, the effect of gravity on the spring-mass system is ignored, and the system is constrained to operate only in the horizontal direction. (Direction) movement.

[0023] In this step, the expression for the external excitation harmonic force is: (1); In the above formula (1), For external excitation simple harmonic force, The amplitude of the externally excited harmonic force, Angular frequency, It is a time variable; The mass motion control equation is: (2); In the above formula (2), , and The equivalent mass of the plate structure. , , and respectively mass , , and acceleration, For connection and The equivalent spring stiffness coefficient, For connection and The equivalent spring stiffness coefficient, For connection and The equivalent spring stiffness coefficient, For quality displacement coordinates, For quality displacement coordinates, For quality displacement coordinates, For quality acceleration, For external excitation simple harmonic force, The equivalent lumped mass of the superstructure.

[0024] Among them, due to the equivalent mass of the plate structure , and Same, therefore = = = , = = .make = , = .

[0025] S32: Perform a Laplace transform on the mass motion control equation to obtain the frequency domain response equation; In this step, based on Laplace's principle, that is... and .

[0026] The frequency domain response equation is: (3); In the above formula (3), This is the equivalent spring stiffness coefficient. The concentrated mass is the equivalent mass of the plate structure. For the complex frequency variable in the Laplace transform domain, For connection quality and The equivalent spring stiffness coefficient, The equivalent lumped mass of the superstructure unit. , , and To be respectively mass , , and Displacement response in the Laplace domain The amplitude of the externally excited harmonic force, , and The equivalent mass of the plate structure.

[0027] S33: Solve the frequency domain response equation according to the incident wave isolation principle to obtain the incident wave expression; In this step, according to Laplace's principle, where .

[0028] The coefficients related to the system parameters are: (4); In the above formula (4), The coefficients are related to the system parameters. This is the equivalent spring stiffness coefficient. The concentrated mass is the equivalent mass of the plate structure. For connection quality and The equivalent spring stiffness coefficient, The equivalent lumped mass of the superstructure unit. Angular frequency; The mass The auxiliary variables are: (5); In the above formula (5), For quality Auxiliary variables, For externally excited simple harmonic forces, This is the equivalent spring stiffness coefficient. The concentrated mass is the equivalent mass of the plate structure. Angular frequency, These are coefficients related to system parameters; The mass The auxiliary variables are: (6); In the above formula (6), For quality Auxiliary variables, For quality displacement response, For externally excited simple harmonic forces, This is the equivalent spring stiffness coefficient. The concentrated mass is the equivalent mass of the plate structure. Angular frequency; The mass The auxiliary variables are: (7); In the above formula (7), For quality Auxiliary variables, For quality displacement response, For connection quality and The equivalent spring stiffness coefficient, The equivalent lumped mass of the superstructure unit. ω is the angular frequency.

[0029] S34: The incident wave expression is analyzed based on the anti-resonance mechanism to obtain the anti-resonance geometric configuration.

[0030] In this step, the isolation of the incident wave indicates the mass unit. The response is zero when ,get It is important to note that It is a unit Its natural frequency. Additionally, when ,but It is zero. This indicates that... and Anti-resonance occurred between them, which was used to prevent waves from... spread to .

[0031] The mass The displacement response is: (8); In the above formula (8), For the solved mass displacement response, For externally excited simple harmonic forces, This is the equivalent spring stiffness coefficient. The concentrated mass is the equivalent mass of the plate structure. Angular frequency, For connection quality and The equivalent spring stiffness coefficient, The equivalent lumped mass of the superstructure.

[0032] S4: Based on the shear deformation characteristics of the zero-order horizontal shear wave, the anti-resonance geometric configuration is derived by combining the cylindrical approximation method and the preset anti-resonance boundary conditions, and the superstructure basic geometric parameter scheme is obtained. In this step, the metamaterial's geometric parameter scheme is used to enable the metamaterial to exhibit excellent mechanical properties at a specific frequency.

[0033] To clarify the specific method for obtaining the geometric parameter scheme of the superstructure, step S4 includes S41 to S45, specifically: S41: Based on the shear deformation characteristics of the zero-order horizontal shear wave, a square is selected as the cross section of the superstructure, and the shape of the superstructure is determined. S42: Based on the wavelength of the zero-order horizontal shear wave in the structural plate, the cross-sectional side length of the superstructure shape is set, and the superstructure size is obtained by combining the cylindrical approximation method and the preset anti-resonance boundary conditions. To clarify the specific method for obtaining the size of the meta-element, step S42 includes S421 to S424, specifically: S421: Set the cross-sectional side length of the superstructure shape according to the wavelength of the zero-order horizontal shear wave in the plate to obtain the cross-sectional width of the superstructure. In this step, the resonant response of the superstructure is enhanced based on the wavelength of the zero-order horizontal shear wave in the plate. The cross-sectional side length of the superstructure is set to half the wavelength of the zero-order horizontal shear wave in the plate, thus obtaining the cross-sectional width of the superstructure.

[0034] S422: Under the excitation of the zero-order horizontal shear wave, the superstructure undergoes torsional deformation, forming a shear warping effect; S423: Based on the cylindrical approximation method and anti-resonance boundary conditions, the superstructure under the shear warping effect is simplified and analyzed. The height of the superstructure is obtained by combining the cylindrical torsion equation. like Figure 2 As shown, a simplified analysis of the superstructure under the shear warping effect is performed, and the square column is approximated as a cylinder. The height of the superstructure is determined by analyzing the torsional anti-resonance of the cylinder.

[0035] When the unit cell exhibits anti-resonance, the unit Remaining stationary indicates that the angular displacement of the superstructure matrix region is zero. Furthermore, the cylinder is subjected to torque. The function of this. The standard equation for cylindrical torsion is: (9); In the above formula (9), For partial derivatives, Let be the angle of torsion of the cylinder. This represents the position of the cylinder along its length. For time variables, The speed at which a wave propagates in a medium. The mass per unit volume of the material. The ability of a material to resist shear deformation; At the excitation end of the cylinder, specific boundary conditions must be met: (10); In the above formula (10), The ability of a material to resist shear deformation, For angle Regarding spatial coordinates The partial derivatives, Let be the angle of torsion of the cylinder. Let be the position coordinates of the cylinder along its length. This represents the position of the cylinder along its length. It is the polar moment of inertia. Angular frequency, The speed at which a wave propagates in a medium. It is a constant. For the amplitude of the excitation force, It is a time variable; Substituting equation (9) into equation (10) yields: (11); In the above formula (11), It is a constant. For the amplitude of the excitation force, The speed at which a wave propagates in a medium. Angular frequency, For time variables, The ability of a material to resist shear deformation, It is the polar moment of inertia. The height of the cylinder; On the other hand, the anti-resonance condition for a cylinder is that the angular displacement at the excitation end is zero, that is: (12); In the above formula (12), Let be the angle of torsion of the cylinder. It is a constant. Angular frequency, It is a time variable; To meet the above conditions, It must be zero, therefore: (13); In the above formula (13), Angular frequency, Let be the height of the cylinder. The speed at which a wave propagates in a medium. It is infinitely large; therefore: (14); In the above formula (14), Angular frequency, Let be the height of the cylinder. Pi It is an integer. The speed at which a wave propagates in a medium; Right now: (15); In the above formula (15), Let be the height of the cylinder. It is an integer. Pi The speed at which a wave propagates in a medium. Angular frequency, λ is the wavelength.

[0036] when The minimum height of the anti-resonance cylinder can be obtained: (16); In the above formula (16), The height of the cylinder Wavelength; Finally, the height of the superstructure was determined to be l / 4.

[0037] S424: The super-module dimensions are obtained by constructing based on the width and height of the super-module cross-section.

[0038] Preferably, the cross-sectional width of the meta-element is / 2, the height of the superstructure cross-section is / 4.

[0039] S43: Perform structural model analysis on a single meta-element based on finite element simulation, and determine the spacing parameters of the meta-element through the finite element simulation results; To clarify the specific method for obtaining the meta-element spacing parameter, step S43 includes S431 to S433, specifically: S431: Based on finite element simulation, a one-dimensional periodic arrangement of multiple superstructure elements is performed to obtain a superstructure. By setting excitation sources and receiving points for the superstructure, the finite element simulation results are obtained. S432: Analyze the relationship between the spacing of the meta-element and the wave transmittance based on the finite element simulation results, and obtain the quantitative relationship curve between the spacing and the wave transmittance. S433: Based on the quantitative relationship curve between the spacing and wave transmittance, determine the spacing between each meta-unit in the metastructure to obtain the meta-unit spacing parameter.

[0040] like Figure 3 As shown, when the height reaches 15.5 mm, the wave transmittance approaches zero, and this is applicable to intervals in the range of 0-30 mm. At this time, the wavelength of the zero-order horizontal shear wave in the plate structure is 62 mm, and the spacing parameter of the meta-element is less than or equal to half the wavelength, which is used to achieve wave isolation of the zero-order horizontal shear wave.

[0041] S44: Evaluate the wave isolation and waveguide performance of the superstructure at the specified dimensions based on the finite element simulation results, and determine the operating bandwidth of the superstructure. like Figure 4As shown, in this step, finite element simulation software was used to simulate the transmission of zero-order horizontal shear waves at different frequencies. The results show that within a 20kHz range around a center frequency of 50kHz, the wave transmittance is less than 0.1, indicating that the meta-element has good wave isolation performance in this frequency range. Simultaneously, the waveguide performance was evaluated, and its operating bandwidth was determined to be 20kHz. Within this bandwidth, the wave transmittance is less than 0.1, demonstrating effective wave isolation.

[0042] S45: Based on the shape of the super-module, the size of the super-module, the spacing parameter of the super-module, and the working bandwidth of the super-module, a scheme is constructed to obtain the geometric parameter scheme of the super-module.

[0043] S5: Based on the optimal size of the superstructure in the aforementioned superstructure geometric parameter scheme, the propagation of the zero-order horizontal shear wave is controlled by superstructures arranged in different ways.

[0044] In this step, meta-elemental units are arranged in a row along a one-dimensional direction as a wave-isolating device to effectively isolate the incident zero-order horizontal shear wave. Furthermore, arranging the meta-elemental units into two rows with arbitrary paths can serve as waveguides, guiding the zero-order horizontal shear wave to propagate along a predetermined path. Based on different arrangements of the meta-elemental units within the geometric parameter scheme, the propagation of the zero-order horizontal shear wave is controlled, enabling flexible control of the wave propagation characteristics. Simulation results show that the meta-elemental units can effectively isolate and guide the propagation of the zero-order horizontal shear wave, demonstrating their excellent wave manipulation capabilities.

[0045] Example 2: This embodiment provides a control device for zero-order horizontal shear waves, the device comprising: The acquisition module is used to acquire individual meta-elemental units and plate structures; The partitioning module is used to partition the individual superstructure and the plate structure into unit cells based on the anti-resonance principle, and to form a spring mass system by constructing equivalent mass from the partitioned unit cells. A module is established to apply a simple harmonic excitation force to the spring-mass system based on Newton's laws of motion, establish the mass motion control equation, and solve the mass motion control equation through an anti-resonance mechanism to obtain the anti-resonance geometric configuration. The derivation module is used to derive the anti-resonance geometric configuration based on the shear deformation characteristics of the zero-order horizontal shear wave, combined with the cylindrical approximation method and preset anti-resonance boundary conditions, to obtain the superstructure basic geometric parameter scheme. To clarify the specific methods for obtaining the derivation module, the following are included: Shape elements are used to select squares as the cross section of the superstructure based on the shear deformation characteristics of the zero-order horizontal shear wave, and to determine the shape of the superstructure. The size unit is used to set the cross-sectional side length of the meta-element shape based on the wavelength of the zero-order horizontal shear wave in the structural plate, and to construct it by combining the cylindrical approximation method and the preset anti-resonance boundary conditions to obtain the size of the meta-element. To clarify the specific methods for obtaining size units, the following are included: A sub-unit is set to set the cross-sectional side length of the superstructure shape according to the wavelength of the zero-order horizontal shear wave in the plate, so as to obtain the cross-sectional width of the superstructure. The deformable subunit is used to generate torsional deformation of the superstructure under the excitation of the zero-order horizontal shear wave, thereby forming a shear warping effect. The first analysis sub-unit is used to perform simplified analysis of the superstructure under the shear warping effect based on the cylindrical approximation method and anti-resonance boundary conditions, and to solve the cylindrical torsion equation to obtain the height of the superstructure. Sub-units are constructed based on the cross-sectional width and cross-sectional height of the super-unit to obtain the super-unit dimensions.

[0046] Spacing elements are used to perform structural model analysis on a single meta-element based on finite element simulation, and to determine the spacing parameters of the meta-element through the finite element simulation results. To clarify the specific methods for obtaining the spacing units, the following are included: The combined sub-unit is used to perform one-dimensional periodic arrangement and combination of multiple superstructure basic elements based on finite element simulation to obtain a superstructure. By setting excitation source and receiving point on the superstructure, the finite element simulation results are obtained. The second analysis subunit is used to analyze the relationship between the spacing of the meta-element and the wave transmittance based on the finite element simulation results, and to obtain a quantitative relationship curve between the spacing and the wave transmittance. The spacing subunit is used to determine the spacing between each meta-element in the metastructure based on the quantitative relationship curve between the spacing and wave transmittance, thereby obtaining the meta-element spacing parameter.

[0047] A bandwidth element is used to evaluate the wave isolation and waveguide performance of the superstructure element size based on the finite element simulation results, and to determine the working bandwidth of the superstructure element. The construction unit is used to construct a scheme based on the shape of the super-primitive, the size of the super-primitive, the spacing parameter of the super-primitive, and the working bandwidth of the super-primitive, so as to obtain the geometric parameter scheme of the super-primitive.

[0048] The control module is used to control the propagation of the zero-order horizontal shear wave by using superstructures with different arrangements, based on the optimal size of the superstructure in the geometric parameter scheme.

[0049] It should be noted that the specific manner in which each module performs its operation in the apparatus described in the above embodiments has been described in detail in the embodiments of the method, and will not be elaborated here.

[0050] Example 3: This embodiment provides a method for applying zero-order horizontal shear waves, the method including: Based on the geometric parameter scheme of the meta-element and the shape of the structure plate to be tested, meta-elements with different arrangements are set up and reserved intervals are reserved to form a waveguide, thus obtaining a waveguide structure; The waveguide structure is arranged along a preset detection target to guide the zero-order horizontal shear wave to propagate along a preset path and determine the propagation direction. An excitation transducer is installed at the beginning of the waveguide, and a receiving transducer is installed at the end. Based on the propagation direction, the zero-order horizontal shear wave is emitted by the excitation transducer for non-destructive testing. When the zero-order horizontal shear wave encounters the defect being tested, it generates a reflected wave or a transmitted wave attenuation. The receiving transducer collects the reflected wave or transmitted wave signal to obtain the defect detection result.

[0051] In this step, the non-destructive testing includes oblique crack detection and bridge deck detection. When detecting oblique cracks, the meta-element is arranged into a linear waveguide along the direction perpendicular to the crack to guide a zero-order horizontal shear wave to be incident perpendicularly on the crack. When detecting bridge decks, the meta-element is arranged into a multi-path waveguide to cover the bridge deck detection area.

[0052] like Figures 5 to 9 As shown, the non-destructive testing includes oblique crack detection and bridge deck inspection, as detailed below: Oblique crack detection: When performing oblique crack detection, the meta-element is arranged into a linear waveguide along the direction perpendicular to the crack to guide the zero-order horizontal shear wave to be incident perpendicularly on the crack.

[0053] The specific implementation steps are as follows: Finite Element Simulation: First, finite element simulation was used to calculate the auxiliary capability of the meta-element. The meta-element was arranged in two rows with a gap between them to form a waveguide, which guides the propagation of the zero-order horizontal shear wave and enhances the amplitude of the reflected echo after the wave interacts with the crack. In the calculation, both the meta-element blocks and the substrate were made of aluminum, with a Young's modulus of 70 GPa, a density of 2700 kg / m³, and a Poisson's ratio of 0.33. Without the meta-element, only the 90° crack reflected echo had a relatively large amplitude; the amplitudes of the reflected echo from cracks at other angles were close to zero. Conversely, after introducing the meta-element, the amplitudes of the reflected echo from cracks at all angles increased significantly, reaching a level that was clearly identifiable.

[0054] Experimental Verification: Further experimental verification was conducted to validate the effectiveness of the meta-element-assisted detection. For example... Figure 6 As shown, in the experimental setup, both the meta-element and the substrate are made of aluminum. A piezoelectric element is used to excite and receive a zero-order horizontal shear wave. The experiment uses a 45° crack as an example. Figure 7 and Figure 8 As shown, the experimentally measured signal contains four wave packets: the first is the zero-order horizontal shear wave directly incident from the excitation end; the second is the boundary reflection echo; the third is the wave received after the boundary reflection echo is reflected again at the crack; and the wave in the gray shaded area represents the crack reflection echo. Among these, Figure 7 In the diagram, (b)-(d) represent crack reflection echoes measured at different frequencies without the meta-element. It can be seen that no crack reflection echoes are observed in these cases. Conversely, when the meta-element is introduced, significant crack reflection echoes can be observed, such as... Figure 8 As shown in (e)-(g) in the figure. This experiment verifies that meta-element can effectively assist in the detection of oblique cracks and has a bandwidth of 20 kHz.

[0055] Bridge deck inspection: When performing bridge deck inspection, the meta-element is arranged into a multi-path waveguide to cover the bridge deck inspection area.

[0056] The specific implementation steps are as follows: like Figure 10 and Figure 11 As shown, the Figure 10 To set up the experiment, introduce cracks into the plate structure. For example... Figure 11 As shown, the experimentally measured signal contains three distinct wave packets: the first wave packet is a zero-order horizontal shear wave directly incident from the excitation end; the second wave packet is a boundary reflection echo; and the third wave packet is a crack reflection echo. It can be seen that although the amplitude of the crack reflection echo wave packet is weakened compared to the incident wave, it is still clearly identifiable. However, without the assistance of the meta-element, the zero-order horizontal shear wave cannot detect cracks outside its propagation range. Therefore, the above results confirm the effective role of this meta-element in assisting in expanding the detection range of the zero-order horizontal shear wave.

[0057] Space constraints make it difficult to arrange transducers and sensors, thus hindering the detection of localized areas. This paper addresses this by introducing meta-elemental structures to construct curved path waveguides, allowing zero-order horizontal shear waves to propagate along arbitrary curved paths instead of straight lines. This expands the propagation range of zero-order horizontal shear waves and provides a new method for detecting confined areas.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0059] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for controlling a zero-order horizontal shear wave, characterized in that, include: Obtain individual meta-elemental units and plate structures; Based on the principle of anti-resonance, the individual superstructure and the plate structure are divided into unit cells. By constructing equivalent mass from the divided unit cells, a spring mass system is formed. Based on Newton's laws of motion, a simple harmonic excitation force is applied to the spring-mass system, and a mass motion control equation is established. The mass motion control equation is then solved through an anti-resonance mechanism to obtain an anti-resonance geometric configuration. Based on the shear deformation characteristics of the zero-order horizontal shear wave, the anti-resonance geometric configuration is derived by combining the cylindrical approximation method and the preset anti-resonance boundary conditions, and the superstructure basic geometric parameter scheme is obtained. Based on the optimal size of the superstructure in the aforementioned superstructure geometric parameter scheme, the propagation of the zero-order horizontal shear wave is controlled by superstructures arranged in different ways.

2. The method for controlling the zero-order horizontal shear wave according to claim 1, characterized in that, Based on the anti-resonance principle, the individual superstructure and the plate structure are divided into unit cells. By constructing equivalent masses from the divided unit cells, a spring-mass system is formed, including: Based on the principle of anti-resonance, the individual superstructure and the plate structure are divided into unit cells to obtain a single unit cell; Equivalent mass modeling is performed on the unit cells to obtain the equivalent mass of the superstructure and the equivalent mass of the plate structure; Based on the connection stiffness characteristics of the plate structure and the superstructure, a harmonic force is applied to the equivalent mass of the superstructure and the equivalent mass of the plate structure to simulate an incident zero-order horizontal shear wave, forming a spring-mass system.

3. The method for controlling the zero-order horizontal shear wave according to claim 1, characterized in that, Based on the shear deformation characteristics of the zero-order horizontal shear wave, and combining the cylindrical approximation method and preset anti-resonance boundary conditions, the anti-resonance geometric configuration is derived, resulting in a superstructure primitive geometric parameter scheme, including: Based on the shear deformation characteristics of the zero-order horizontal shear wave, a square shape is selected as the cross section of the superstructure, and the shape of the superstructure is determined. Based on the wavelength of the zero-order horizontal shear wave in the structural plate, the cross-sectional side length of the superstructure shape is set, and the superstructure size is obtained by combining the cylindrical approximation method and the preset anti-resonance boundary conditions. Structural model analysis of a single superstructure element is performed based on finite element simulation, and the spacing parameters of the superstructure element are determined through the finite element simulation results. The wave isolation and waveguide performance of the superstructure at the given dimensions are evaluated based on the finite element simulation results, and the operating bandwidth of the superstructure is determined. Based on the shape of the super-primitive, the size of the super-primitive, the spacing parameters of the super-primitive, and the working bandwidth of the super-primitive, a scheme is constructed to obtain the geometric parameter scheme of the super-primitive.

4. The method for controlling the zero-order horizontal shear wave according to claim 3, characterized in that, Based on the wavelength of the zero-order horizontal shear wave in the structural plate, the cross-sectional side length of the meta-element shape is set, and constructed using the cylindrical approximation method and preset anti-resonance boundary conditions to obtain the meta-element dimensions, including: The cross-sectional side length of the superstructure is set according to the wavelength of the zero-order horizontal shear wave in the plate to obtain the cross-sectional width of the superstructure. The superstructure undergoes torsional deformation under the excitation of the zero-order horizontal shear wave, resulting in a shear warping effect. The superstructure under the shear warping effect is simplified and analyzed based on the cylindrical approximation method and anti-resonance boundary conditions. The height of the superstructure is obtained by combining the cylindrical torsion equation. The superstructure dimensions are obtained by constructing the superstructure based on its cross-sectional width and cross-sectional height.

5. The method for controlling the zero-order horizontal shear wave according to claim 3, characterized in that, Structural model analysis of a single meta-element is performed based on finite element simulation. The spacing parameters of the meta-element are determined through the finite element simulation results, including: Based on finite element simulation, a one-dimensional periodic arrangement of multiple superstructure elements is performed to obtain a superstructure. By setting excitation sources and receiving points for the superstructure, finite element simulation results are obtained. Based on the finite element simulation results, the relationship between the spacing of the meta-element and the wave transmittance is analyzed, and a quantitative relationship curve between the spacing and the wave transmittance is obtained. Based on the quantitative relationship curve between the spacing and wave transmittance, the spacing between each meta-unit in the metastructure is determined, and the meta-unit spacing parameter is obtained.

6. A control device for a zero-order horizontal shear wave, characterized in that, include: The acquisition module is used to acquire individual meta-elemental units and plate structures; The partitioning module is used to partition the individual superstructure and the plate structure into unit cells based on the anti-resonance principle, and to form a spring mass system by constructing equivalent mass from the partitioned unit cells. A module is established to apply a simple harmonic excitation force to the spring-mass system based on Newton's laws of motion, establish the mass motion control equation, and solve the mass motion control equation through an anti-resonance mechanism to obtain the anti-resonance geometric configuration. The derivation module is used to derive the anti-resonance geometric configuration based on the shear deformation characteristics of the zero-order horizontal shear wave, combined with the cylindrical approximation method and preset anti-resonance boundary conditions, to obtain the superstructure basic geometric parameter scheme. The control module is used to control the propagation of the zero-order horizontal shear wave by using superstructures with different arrangements, based on the optimal size of the superstructure in the geometric parameter scheme.

7. The control device for zero-order horizontal shear wave according to claim 6, characterized in that, The derivation module includes: Shape elements are used to select squares as the cross section of the superstructure based on the shear deformation characteristics of the zero-order horizontal shear wave, and to determine the shape of the superstructure. The size unit is used to set the cross-sectional side length of the meta-element shape based on the wavelength of the zero-order horizontal shear wave in the structural plate, and to construct it by combining the cylindrical approximation method and the preset anti-resonance boundary conditions to obtain the size of the meta-element. Spacing elements are used to perform structural model analysis on a single meta-element based on finite element simulation, and to determine the spacing parameters of the meta-element through the finite element simulation results. A bandwidth element is used to evaluate the wave isolation and waveguide performance of the superstructure element size based on the finite element simulation results, and to determine the working bandwidth of the superstructure element. The construction unit is used to construct a scheme based on the shape of the super-primitive, the size of the super-primitive, the spacing parameter of the super-primitive, and the working bandwidth of the super-primitive, so as to obtain the geometric parameter scheme of the super-primitive.

8. The control device for zero-order horizontal shear wave according to claim 7, characterized in that, The size unit includes: A sub-unit is set to set the cross-sectional side length of the superstructure shape according to the wavelength of the zero-order horizontal shear wave in the plate, so as to obtain the cross-sectional width of the superstructure. The deformable subunit is used to generate torsional deformation of the superstructure under the excitation of the zero-order horizontal shear wave, thereby forming a shear warping effect. The first analysis sub-unit is used to perform simplified analysis of the superstructure under the shear warping effect based on the cylindrical approximation method and anti-resonance boundary conditions, and to solve the cylindrical torsion equation to obtain the height of the superstructure. Sub-units are constructed based on the cross-sectional width and cross-sectional height of the super-unit to obtain the super-unit dimensions.

9. The control device for zero-order horizontal shear wave according to claim 7, characterized in that, The spacing unit includes: The combined sub-unit is used to perform one-dimensional periodic arrangement and combination of multiple superstructure basic elements based on finite element simulation to obtain a superstructure. By setting excitation source and receiving point on the superstructure, the finite element simulation results are obtained. The second analysis subunit is used to analyze the relationship between the spacing of the meta-element and the wave transmittance based on the finite element simulation results, and to obtain a quantitative relationship curve between the spacing and the wave transmittance. The spacing subunit is used to determine the spacing between each meta-element in the metastructure based on the quantitative relationship curve between the spacing and wave transmittance, thereby obtaining the meta-element spacing parameter.

10. A method for applying a zero-order horizontal shear wave, comprising using a control method for a zero-order horizontal shear wave as described in any one of claims 1-5, characterized in that, include: Based on the geometric parameter scheme of the meta-element and the shape of the structure plate to be tested, meta-elements with different arrangements are set up and reserved intervals are reserved to form a waveguide, thus obtaining a waveguide structure; The waveguide structure is arranged along a preset detection target to guide the zero-order horizontal shear wave to propagate along a preset path and determine the propagation direction. An excitation transducer is installed at the beginning of the waveguide, and a receiving transducer is installed at the end. Based on the propagation direction, the zero-order horizontal shear wave is emitted by the excitation transducer for non-destructive testing. When the zero-order horizontal shear wave encounters the defect being tested, it generates a reflected wave or a transmitted wave attenuation. The receiving transducer collects the reflected wave or transmitted wave signal to obtain the defect detection result.

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