Method and system for detecting damage of steel-concrete composite bridge connecting piece

Abstract

The invention relates to an intelligent detection technology, in particular to a steel-concrete composite bridge connecting piece damage detection method and system. According to the scheme, the reference data are obtained through finite element modeling, the echo data corresponding to the connecting pieces are extracted and reconstructed in combination with the measured data, then processing is conducted in combination with the reference echo data, the connecting pieces with damage defects can be rapidly detected and positioned, the intelligent level of detection and the detection efficiency are greatly improved, and the detection accuracy is improved. And manpower and material resource cost is saved, and more reliable support is provided for subsequent repair and maintenance work. The data is further processed by introducing a correction compensation mechanism and a corresponding detection scheme through a corresponding waveform reconstruction technology, so that the data is closer to the actual situation, the influence caused by various interference factors is greatly reduced, the prediction capability of the echo data of the connecting piece is improved, the structural state can be evaluated more accurately, and the reliability of the connecting piece is improved. And the detection precision and reliability are obviously improved.

Description

Technical Field

[0001] The present application relates to intelligent detection technology, and specifically to a method and system for detecting damage to connectors of a steel-concrete composite bridge. Background Art

[0002] Steel-concrete composite beams are usually composed of steel beam modules and concrete modules (or flange plates). The steel beam modules play the main load-bearing role, while the concrete modules protect the steel beams and enhance the integrity. Shear connectors (such as studs, channels, bending bars, etc.) are set between the two to resist the lifting and relative slippage at the interface, so that they can work together as a whole. In high-performance concrete composite bridge decks, shear connectors with good shear resistance are the basic prerequisite for ensuring the coordinated work of the two key load-bearing components, the high-performance concrete structural layer and the steel bridge deck, throughout the life cycle, and thus ensuring the stability of the mechanical properties of the structural system.

[0003] However, with the use of composite bridges, their shear connectors will also suffer fatigue damage under the action of dynamic loads on the bridge deck, and timely inspection and repair are required. The inspection methods used in the prior art are: first, to inspect each connector separately in the steel box girder, which requires a lot of manpower and material resources; second, to inspect by combining simulation methods, but the existing simulation process does not fully consider various actual interferences, resulting in false detection and misjudgment. Summary of the invention

[0004] Based on this, the present application proposes a method and system for detecting damage to steel-concrete composite bridge connectors to address the above-mentioned problems, aiming to improve the efficiency of detecting damage to steel-concrete composite bridge connectors while improving the accuracy of detection.

[0005] On one hand, the present application provides a method for detecting damage to a steel-concrete composite bridge connector, the method comprising:

[0006] Establishing a finite element model of the steel-concrete composite bridge;

[0007] Acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge;

[0008] When each connecting member is in an intact state, a corresponding stress wave is applied to a corresponding preset position of the finite element model, and reference echo data of the dynamic response is obtained;

[0009] Extracting characteristic information of each connector from the reference echo data;

[0010] Extracting and reconstructing echo data generated by each connecting member from the actual echo data based on the characteristic information to obtain reconstructed echo data;

[0011] The connecting parts of the target composite bridge are inspected for damage according to the reconstructed echo data and the reference echo data.

[0012] Furthermore, the method further comprises:

[0013] Extracting frequency parameters and time parameters of echoes generated by each connector in the reference echo data;

[0014] Aligning the actual echo data with the reference echo data in time;

[0015] Extracting waveform data corresponding to a preset time width of each peak or trough time point of the actual waveform and the reference echo data;

[0016] A bandpass filter is constructed based on the frequency parameters of the reference echo data to filter each extracted waveform data, and the filtered waveform is reconstructed.

[0017] Preferably, the step of constructing a bandpass filter based on the frequency parameters of the reference echo data to filter each extracted waveform data comprises:

[0018] Simulating the corresponding connector of the finite element model under different damage states and determining the frequency range of the echo under the damage state;

[0019] Based on the reference echo data frequency and the frequency range in the lossy state, the center frequency and bandwidth are determined and a bandpass filter is constructed to filter each extracted waveform.

[0020] Furthermore, the method further comprises:

[0021] The waveforms corresponding to the respective connectors in the reconstructed echo data and the reference echo data are sampled one by one according to a preset sampling frequency;

[0022] Calculate the similarity R between the reconstructed echo and the reference echo of each connector j :

[0023]

[0024] Among them, R j is the similarity of the reconstructed echo corresponding to the jth connector relative to the reference echo, x ij ,y ij are the i-th sampling data of the reconstructed echo and the reference echo corresponding to the j-th connector, are the means of the sampling data corresponding to the reconstructed echo and the reference echo, respectively, and n is the number of sampling points;

[0025] The target connecting parts whose screening correlation is less than a preset first threshold value are determined to have damage defects.

[0026] Preferably, the method further comprises:

[0027] Determine a reference attenuation value of the corresponding amplitude of each connector in the reference echo data relative to the previous peak / trough amplitude;

[0028] Calculate the actual attenuation value of the peak corresponding to each connector in the reconstructed echo relative to the amplitude of the previous peak / trough;

[0029] The difference between the corresponding actual attenuation value and the reference attenuation value is compared, and if the difference exceeds a preset second threshold, it is determined that the corresponding connecting component has a damage defect.

[0030] Further, the method comprises:

[0031] Extract defect feature data corresponding to the damaged defective connectors along the time axis;

[0032] Determining a time compensation parameter and / or an amplitude compensation parameter based on the defect characteristic data;

[0033] Based on the time compensation parameter and / or amplitude compensation parameter, time and / or amplitude compensation correction is performed on the echo data of each connecting member behind the connecting member with the damage defect.

[0034] Furthermore, the method further comprises:

[0035] Shielding the concrete part of the finite element model, loading a stress wave at a preset position of the finite element model, and acquiring a dynamic response echo as reference echo data;

[0036] Loading the stress wave to a preset position of the finite element model that is not shielded from any structure, and acquiring a second dynamic response echo;

[0037] taking the difference between the reference echo and the second echo as interference echo data;

[0038] Arranging an ultrasonic array at a point corresponding to a preset position of the target combined bridge, emitting the stress wave through the ultrasonic array, and receiving a corresponding reflected echo;

[0039] The difference between the reflected echo and the interference echo data is used as the actual echo data.

[0040] The second aspect of the present application also provides a steel-concrete composite bridge connector damage detection system, the system comprising:

[0041] A model building unit, used to build a finite element model of the steel-concrete composite bridge;

[0042] A data acquisition unit, used to acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge;

[0043] A data simulation unit, used for applying corresponding stress waves to corresponding preset positions of the finite element model when each connecting member is in a non-destructive state, and obtaining reference echo data of dynamic response;

[0044] A waveform reconstruction unit, used to extract characteristic information of each connector from the reference echo data; extract and reconstruct target echo data generated by each connector from the actual echo data based on the characteristic information;

[0045] A damage detection unit is used to perform damage detection on the connecting parts of the target combined bridge according to the reconstructed echo data of the connecting parts and the reference echo data.

[0046] The third aspect of the present application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of any one of the above methods.

[0047] A fourth aspect of the present application provides a computer terminal device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of any one of the above methods.

[0048] The above-mentioned steel-concrete composite bridge connector damage detection scheme provided in this application obtains benchmark data through finite element modeling and extracts and reconstructs echo data corresponding to each connector in combination with measured data, and then processes it in combination with the benchmark echo data, which helps to quickly detect and locate connectors with damage defects, greatly improves the intelligence level and efficiency of detection, saves manpower and material costs, and provides more reliable support for subsequent repair and maintenance work. Further processing of the data through corresponding waveform reconstruction technology and introduction of correction compensation mechanism and corresponding detection scheme makes the data closer to the actual situation, greatly reduces the impact of various interference factors, improves the prediction ability of connector echo data, helps to more accurately evaluate the structural status, and significantly improves the accuracy and reliability of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] in:

[0051] Figure 1 is a flow chart of a method for detecting damage to a connection member of a steel-concrete composite bridge in one embodiment;

[0052] Figure 2 is a structural block diagram of a steel-concrete composite bridge connector damage detection system in one embodiment;

[0053] Figure 3 FIG. 4 is a structural block diagram of a computer device in one embodiment. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, 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.

[0055] The terms "include", "comprising" and "having" and any variations thereof in the specification and claims of the present application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices. In the claims, specification and drawings of the present application, relational terms such as "first" and "second" are merely used to distinguish one entity / operation / object from another entity / operation / object, and do not necessarily require or imply any such actual relationship or order between these entities / operations / objects.

[0056] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The occurrence of the phrase at various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0057] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0058] In one embodiment, if Figure 1 The flowchart of the present invention is a method for detecting damage to a steel-concrete composite bridge connector. The method comprises:

[0059] S10, establishing a finite element model of the steel-concrete composite bridge.

[0060] Specifically, the precise finite element geometric model of the steel-concrete composite bridge is established using finite element processing software (such as Ansys, Abaqus, Midas, etc.), including concrete slabs, steel beams and shear connectors, the upper structure of which is high-performance concrete, and the lower structure is a steel box beam structure. Then, the geometric model is meshed to generate a finite element mesh, and the units and nodes in the model are determined. The material properties (such as elastic modulus, density) and geometric parameters of each unit are based on the actual size, material properties (such as elastic modulus, density, Poisson's ratio, etc.) and boundary conditions of the steel-concrete composite beam. In the model, ensure that the geometric shape, size and arrangement of the connectors (such as shear studs, bolts, etc.) are consistent with the actual situation, so that the model can be subsequently subjected to modal analysis under different states to obtain parameters such as vibration mode and frequency of each order mode.

[0061] S11. Acquire actual echo data generated by applying a preset stress wave at a preset position of the target steel-concrete composite bridge.

[0062] The present application scheme is based on ultrasonic detection, which is based on the propagation characteristics of ultrasound in materials. When ultrasound encounters different interfaces in the material (such as connectors), it will produce reflections. When the connectors are damaged, it will affect the propagation of ultrasound in the material. Its reflection, transmission and diffraction will be different from those of undamaged connectors. The corresponding echo emission energy and propagation speed will also vary with the depth and type of damage. The location of the damaged connector can be identified by analyzing the waveform data (peaks, time intervals) of these reflected echo waves.

[0063] Preferably, in one embodiment, the present application arranges an array of ultrasonic sensors at a preset position of the steel-concrete composite beam (such as a position near a portion of the connecting pieces of the steel beam), and these sensors are used to transmit and receive ultrasonic signals. The ultrasonic sensors can be arranged at multiple intervals to ensure that the arrangement of the sensors can cover all the connecting pieces that need to be detected, and the distance between the sensors is moderate so that the reflected signals can be accurately captured.

[0064] Furthermore, an ultrasonic signal is emitted by the sensor, and the signal will propagate inside the composite beam in the form of a stress wave. The signal may be in the form of a modulated sine signal, a swept frequency signal, or a pulse signal, etc. The intensity of the emitted signal should be moderate to ensure that the signal can penetrate the composite beam and generate sufficient reflection at the connector. After the preset ultrasonic sensor array emits and receives the corresponding echo data, the echo data is recorded and uploaded to the data processing center for subsequent analysis and detection.

[0065] S12. When each connector is in an intact state, a corresponding stress wave is applied to a preset position corresponding to the finite element model, and a dynamic response echo is obtained to obtain reference echo data.

[0066] In one embodiment of the present application, a finite element model is first used to simulate the corresponding stress wave at the preset position of each connector in a lossless state, and the applied stress wave, position and simulation conditions (such as frequency, propagation path, amplitude attenuation, speed, scattering and other information) are consistent with the actual conditions to simulate the response of the structure to the excitation. The propagation of ultrasonic waves is simulated in the finite element model, and the echo data of the dynamic response reflection is simulated and obtained in a lossless state as the initial reference echo data.

[0067] Further preferably, in one embodiment of the present application, in order to eliminate the interference and influence of the concrete part on the echo data and improve the accuracy of the data and the accuracy of subsequent detection, the present application also includes further optimization of the actual echo data and the reference echo data of steps S11 and S12, specifically including:

[0068] Step A, shielding the concrete part of the finite element model, loading a stress wave at a preset position of the finite element model, and obtaining a dynamic response echo as reference echo data;

[0069] Step B, loading the stress wave to a preset position of the finite element model that is not shielded from any structure, and obtaining a second dynamic response echo;

[0070] Step C, taking the difference between the reference echo and the second echo as the interference echo data;

[0071] Step D: taking the difference between the echo data in step S11 and the interference echo data as the final actual echo data.

[0072] The above-mentioned embodiment of the present application shields the concrete part of the finite element model and eliminates the echo interference that may be generated by the superstructure. The interference response spectrum generated in the case of homogeneous concrete can be calculated through the difference between the second echo and the reference echo after interference removal. Further, based on the difference between the actual detection result and the interference response spectrum, most of the influence of actual concrete in the actual detection can be eliminated. The echo generated by the uneven distribution inside the concrete will be eliminated in the subsequent peak screening. The main reason is that the attenuation of ultrasonic waves in concrete is much greater than that in steel structures. This will help to reduce data interference and detection accuracy in the future.

[0073] S13, extracting characteristic information of each connector from the reference echo data, and extracting and reconstructing echo data generated by each connector from the actual echo data based on the characteristic information to obtain reconstructed echo data.

[0074] In one embodiment of the present application, in order to more accurately identify and extract the echo signal generated by the connector from the actual echo data, after the connector echo data is extracted from the finite element reference echo data, feature information extraction and actual connector echo reconstruction are further performed, specifically including:

[0075] S131, extracting the frequency parameters and time parameters of the echo generated by each connector in the reference echo data.

[0076] Preferably, in one embodiment of the present application, the reference echo data is extracted at each preset time interval using a sliding window of preset width, and waveforms with multiple peaks or troughs greater than a preset value are obtained as the characteristic echo data of the connector, and the reference echo data of each connector is obtained, wherein each preset time interval Δt i satisfy:

[0077]

[0078] Where, ΔL i is the distance between the i-th connector and the i-1-th connector, and v is the propagation speed of the stress wave under the current conditions.

[0079] After identifying and extracting the reference echo data of each connector, feature extraction is performed on the reference echo data of each connector. The feature information generally includes parameters such as frequency, phase, amplitude, and time of the signal.

[0080] S132: Align the actual echo data and the reference echo data in time.

[0081] Specifically, in one embodiment of the present application, the time parameters are unified, and the correlation between the actual echo signal and the reference echo data is determined and calculated to determine the time delay and adjustment coefficient between the two, and the received measured echo signal is shifted or adjusted in time to achieve temporal alignment of the actual echo data and the reference echo signal.

[0082] S133, extracting waveform data corresponding to the preset time width of each peak time point of the actual waveform and the reference echo data.

[0083] Preferably, since the echo data generated by each connector may be different, the amplitude, time center and width of the echo may also be different. Therefore, in one embodiment of the present application, based on the time points of each peak of the benchmark data, the corresponding extraction time center is determined, and a certain time width is used as the time width parameter to extract the corresponding waveform data of the actual waveform and the vicinity of each peak time point of the benchmark echo data. The time width can be determined based on the current waveform width of each waveform of the benchmark waveform data, and a certain adjustment value is appropriately added to prevent the target waveform from being missed due to the propagation time misalignment and deviation caused by some damage in the actual echo.

[0084] Furthermore, when extracting a specific waveform, the envelope detection processing method can be used to perform envelope detection and extraction on the waveform of the corresponding time point and time width to extract the envelope information of the signal. Envelope detection is a commonly used signal processing technology that can retain the amplitude and phase information of the signal.

[0085] S134, constructing a bandpass filter based on the frequency parameters of the reference echo data to filter each extracted waveform, and reconstructing the filtered waveform.

[0086] Specifically, according to the above echo data extraction, the echo signal corresponding to the connector can be roughly located and extracted, and the actual echo data can be reconstructed to separate the echo signal generated by the connector. The calculation method of signal reconstruction may involve filtering reconstruction, wavelet reconstruction, neural network reconstruction, etc. In one embodiment, the interference signal generated by other structural elements in the actual echo data can be removed by filtering technology to obtain the echo signal generated by the connector, and further reconstruct the echo data on the same time axis based on the time axis parameters.

[0087] Preferably, the step of constructing a bandpass filter based on the frequency parameters of the reference echo data to filter each extracted waveform comprises:

[0088] S1341, simulating the corresponding connector of the finite element model under different damage states and determining the frequency range of the echo under the damage state;

[0089] S1342. Based on the reference echo data frequency and the frequency range in the lossy state, determine the center frequency and bandwidth and construct a bandpass filter to filter each extracted waveform.

[0090] Specifically, for the detection of steel-concrete composite beam connectors, the center frequency should be the frequency of the main echo signal that is expected to be received. By extracting the approximate frequency and frequency range of the main echo signal, the upper and lower frequency limits are determined, and then the center frequency can be calculated:

[0091] f c =(f h +f l ) / 2,

[0092] Among them, f l is the lower cutoff frequency, f h is the upper cutoff frequency.

[0093] The bandwidth can be further determined by the frequency range. The bandwidth can be calculated by the lower cutoff frequency and the upper cutoff frequency: BW = f h -f lAccording to the above parameters, a bandpass filter is designed to allow signals within a specific frequency range to pass through while attenuating frequencies outside the range, and a corresponding analog filter or digital filter is set to filter to obtain echo data within the specific frequency range generated by the connector.

[0094] The above scheme of the present application combines finite element echo information and signal processing technology to extract the echo signal generated by the connector from the actual echo information. The process involves multiple steps such as data preparation, signal processing, feature extraction, and signal reconstruction, which provides a good data processing foundation for the subsequent effective identification and positioning of connector damage.

[0095] S14. Perform damage detection on the connectors of the target composite bridge according to the reconstructed echo data and the reference echo data.

[0096] Preferably, in one embodiment, the solution of the present application performs damage detection on the connector of the target composite bridge according to the reconstructed echo data and the reference echo data, including:

[0097] S141 . Sample the waveforms corresponding to the respective connectors in the reconstructed echo data and the reference echo data one by one at a preset sampling frequency.

[0098] S142, calculating the similarity R between the reconstructed echo corresponding to each connector and the corresponding reference echo j :

[0099]

[0100] Among them, R j is the similarity of the reconstructed echo corresponding to the jth connector relative to the reference echo, x ij ,y ij are the i-th sampling data of the reconstructed echo and the reference echo corresponding to the j-th connector, are the corresponding means respectively, and n is the number of sampling points.

[0101] S143, screening target connectors whose correlation is less than a preset first threshold to determine if they have damage defects.

[0102] and / or

[0103] Preferably, in another embodiment, the solution of the present application performs damage detection on the connector of the target composite bridge according to the reconstructed echo data and the reference echo data, comprising:

[0104] S141, determining a reference attenuation value of the corresponding amplitude of each connector in the reference echo data relative to the previous peak / trough amplitude.

[0105] S142, calculating the actual attenuation value of the peak corresponding to each connector in the reconstructed echo relative to the amplitude of the previous peak / trough.

[0106] S143, comparing the difference between the corresponding actual attenuation value and the reference attenuation value, if the difference exceeds a preset second threshold, determining that the corresponding connecting component has a damage defect.

[0107] In the above implementation scheme of the present application, ultrasonic detection is based on the propagation characteristics of ultrasonic waves in materials. When ultrasonic waves encounter different interfaces in materials (such as connectors), they will be reflected. When the connector is damaged, it will affect the propagation of ultrasonic waves in the material. Its reflection, transmission and diffraction will be different from those of undamaged connectors. The corresponding echo emission energy, attenuation and propagation speed will also vary with the depth and type of damage. The present application solution can identify the location of damaged connectors by reconstructing the connector echo data and the reference waveform data to analyze the data of these reflected echoes (waveform, peak, time interval).

[0108] In the above-mentioned damage detection and identification implementation scheme of the present application, by comparing the sampled waveform data to reconstruct the connector echo data and the reference waveform data, and combining the corresponding waveform calculation algorithm to compare and calculate the waveform similarity, the waveform of damage defects can be better identified, and the damaged connector can be located.

[0109] and / or,

[0110] Since the reflected echo needs to propagate through other connecting parts in front, if a certain connecting part in front is damaged, it may also affect the propagation of the echo of the subsequent connecting parts. Therefore, the present application introduces the attenuation value of the actual reflected echo relative to the echo of the previous connecting part and compares it with the corresponding benchmark attenuation value. This can better avoid the fact that the calculation results of the finite element model generally have certain differences from the actual project, thereby reducing the error in the comparison process. Using the connecting part as a benchmark to calculate the benchmark attenuation value will provide a better implementation basis for subsequent comparisons.

[0111] Furthermore, in order to further improve the validity of data and the accuracy of detection results, and reduce the interference of the possible connector damage on the echo propagation agent, the present application solution further includes:

[0112] S15, extracting defect feature data corresponding to the damaged defective connectors along the time axis.

[0113] S16. Determine a time compensation parameter and / or an amplitude compensation parameter based on the defect characteristic data.

[0114] S17, based on the time compensation parameter and / or amplitude compensation parameter, the echo data of each connector behind the connector with a damage defect is corrected in time and / or amplitude, and the time and / or amplitude parameters after the final compensation and correction meet the following conditions:

[0115]

[0116] Among them, t i '、A i ' are the time and amplitude parameters of the i-th echo data after compensation and correction, t i , A i are the time and amplitude parameters of the i-th echo before compensation correction, Δt l , β l They are respectively the time compensation parameters and amplitude compensation parameters corresponding to the lth damaged connecting component in front of the ith connecting component, wherein the time compensation parameters and amplitude compensation parameters can be calculated with the time parameters and amplitude parameters corresponding to the reference echo data.

[0117] Further preferably, when the above scheme of the present application is implemented, each connector is inspected one by one along the time axis according to the echo data, and each time a damaged defective connection is identified and detected, compensation and correction of subsequent echo data is initiated to improve the real-time and accuracy of subsequent detection data.

[0118] The above-mentioned steel-concrete composite bridge connector damage detection scheme provided in this application obtains benchmark data through finite element modeling and extracts and reconstructs echo data corresponding to each connector in combination with measured data, and then processes it in combination with the benchmark echo data, which helps to quickly detect and locate connectors with damage defects, greatly improves the intelligence level and efficiency of detection, saves manpower and material costs, and provides more reliable support for subsequent repair and maintenance work. Further processing of the data through corresponding waveform reconstruction technology and introduction of correction compensation mechanism and corresponding detection scheme makes the data closer to the actual situation, greatly reduces the impact of various interference factors, improves the prediction ability of connector echo data, helps to more accurately evaluate the structural status, and significantly improves the accuracy and reliability of detection.

[0119] The second aspect of the present application further provides a steel-concrete composite bridge connector damage detection system, the system comprising:

[0120] A model building unit, used to build a finite element model of the steel-concrete composite bridge;

[0121] A data acquisition unit, used to acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge;

[0122] A data simulation unit, used for applying corresponding stress waves to corresponding preset positions of the finite element model when each connecting member is in a non-destructive state, and obtaining reference echo data of dynamic response;

[0123] A waveform reconstruction unit, used to extract characteristic information of each connector from the reference echo data; extract and reconstruct target echo data generated by each connector from the actual echo data based on the characteristic information;

[0124] A damage detection unit is used to perform damage detection on the connecting parts of the target combined bridge according to the reconstructed echo data of the connecting parts and the reference echo data.

[0125] In one embodiment, the present application further provides a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor performs the following steps:

[0126] Establishing a finite element model of the steel-concrete composite bridge;

[0127] Acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge;

[0128] When each connecting member is in an intact state, a corresponding stress wave is applied to a corresponding preset position of the finite element model, and reference echo data of the dynamic response is obtained;

[0129] Extracting characteristic information of each connector from the reference echo data, extracting and reconstructing echo data generated by each connector from the actual echo data based on the characteristic information, to obtain reconstructed echo data;

[0130] The connecting parts of the target composite bridge are inspected for damage according to the reconstructed echo data and the reference echo data.

[0131] In one embodiment, Figure 3 The present application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the following steps:

[0132] Establishing a finite element model of the steel-concrete composite bridge;

[0133] Acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge;

[0134] When each connecting member is in an intact state, a corresponding stress wave is applied to a corresponding preset position of the finite element model, and reference echo data of the dynamic response is obtained;

[0135] Extracting characteristic information of each connector from the reference echo data, and extracting and reconstructing echo data generated by each connector from the actual echo data based on the characteristic information to obtain reconstructed echo data;

[0136] The connecting parts of the target composite bridge are inspected for damage according to the reconstructed echo data and the reference echo data.

[0137] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0138] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for detecting damage to a steel-concrete composite bridge connector, characterized in that: The method comprises: Establishing a finite element model of the steel-concrete composite bridge; Acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge; When each connecting member is in an intact state, a corresponding stress wave is applied to a corresponding preset position of the finite element model, and reference echo data of the dynamic response is obtained; Extracting characteristic information of each connector from the reference echo data, and extracting and reconstructing echo data generated by each connector from the actual echo data based on the characteristic information to obtain reconstructed echo data; The connecting parts of the target composite bridge are inspected for damage according to the reconstructed echo data and the reference echo data.

2. The method according to claim 1, characterized in that: The method further comprises: Extracting frequency parameters and time parameters of echoes generated by each connector in the reference echo data; Aligning the actual echo data with the reference echo data in time; Providing waveform data corresponding to the preset time width of each peak time point of the actual waveform and the reference echo data; A bandpass filter is constructed based on the frequency parameters of the reference echo data to filter each extracted waveform data, and the filtered waveform is reconstructed.

3. The method according to claim 2, characterized in that The step of constructing a bandpass filter based on the frequency parameters of the reference echo data to filter each extracted waveform data comprises: Simulating the corresponding connector of the finite element model under different damage states and determining the frequency range of the echo under the damage state; Based on the reference echo data frequency and the frequency range in the lossy state, the center frequency and bandwidth are determined and a bandpass filter is constructed to filter each extracted waveform.

4. The method according to claim 2, characterized in that: The method comprises: The waveforms corresponding to the respective connectors in the reconstructed echo data and the reference echo data are sampled one by one according to a preset sampling frequency; Calculate the similarity R between the reconstructed echo and the reference echo of each connector j : Among them, R j is the similarity of the reconstructed echo corresponding to the jth connector relative to the reference echo, x ij ,y ij are the i-th sampling data of the reconstructed echo and the reference echo corresponding to the j-th connector, are the means of the sampling data corresponding to the reconstructed echo and the reference echo, respectively, and n is the number of sampling points; The target connecting parts whose screening correlation is less than a preset first threshold value are determined to have damage defects.

5. The method according to claim 2, characterized in that: The method further comprises: Determine a reference attenuation value of the corresponding amplitude of each connector in the reference echo data relative to the previous peak / trough amplitude; Calculate the actual attenuation value of the peak corresponding to each connector in the reconstructed echo relative to the amplitude of the previous peak / trough; The difference between the corresponding actual attenuation value and the reference attenuation value is compared, and if the difference exceeds a preset second threshold, it is determined that the corresponding connecting component has a damage defect.

6. The method according to any one of claims 1 to 5, characterized in that: The method comprises: Extract defect feature data corresponding to the damaged defective connectors along the time axis; Determining a time compensation parameter and / or an amplitude compensation parameter based on the defect characteristic data; Based on the time compensation parameter and / or amplitude compensation parameter, time and / or amplitude compensation correction is performed on the echo data of each connecting member behind the connecting member with damage defect.

7. The method according to any one of claims 1 to 5, characterized in that: The method further comprises: Shielding the concrete part of the finite element model, loading a stress wave at a preset position of the finite element model, and acquiring a dynamic response echo as reference echo data; Loading the stress wave to a preset position of the finite element model that is not shielded from any structure, and acquiring a second dynamic response echo; taking the difference between the reference echo and the second echo as interference echo data; Arranging an ultrasonic array at a point corresponding to a preset position of the target combined bridge, emitting the stress wave through the ultrasonic array, and receiving a corresponding reflected echo; The difference between the reflected echo and the interference echo data is used as the actual echo data.

8. A steel-concrete composite bridge connector damage detection system, characterized in that: The system comprises: A model building unit, used to build a finite element model of the steel-concrete composite bridge; A data acquisition unit, used to acquire actual echo data generated by applying a preset stress wave at a preset position of a target steel-concrete composite bridge; A data simulation unit, used for applying corresponding stress waves to corresponding preset positions of the finite element model when each connecting member is in a non-destructive state, and obtaining reference echo data of dynamic response; A waveform reconstruction unit, used to extract characteristic information of each connector from the reference echo data, and extract and reconstruct target echo data generated by each connector from the actual echo data based on the characteristic information; A damage detection unit is used to perform damage detection on the connecting parts of the target combined bridge according to the reconstructed echo data of the connecting parts and the reference echo data.

9. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method according to any one of claims 1 to 7.

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