Concrete structure integrity evaluation method and device based on wave velocity image diagnosis

Abstract

The invention provides a concrete structure integrity evaluation method and device based on wave velocity image diagnosis, and is applied to the technical field of geophysical exploration, and the method comprises the steps: obtaining a vibration signal, monitored by a vibration sensor in real time, of a concrete structure; when the vibration signal exceeds a preset vibration threshold value, determining the vibration signal as a target vibration signal; identifying the target vibration signal, and when the target vibration signal is an internal micro-seismic signal of the concrete structure, determining the arrival time of a first arrival wave of the target vibration signal; on the basis of a speed model generated by preorder iteration, arrival time inversion positioning is carried out on arrival time of the first arrival waves, and focus coordinates of the target vibration signals are obtained; constructing a dynamic speed model based on the arrival time of the first arrival wave and the focus coordinates; and performing real-time evaluation and damage trend analysis on the interior of the concrete structure based on the dynamic speed model. According to the invention, high-precision real-time monitoring of the wave velocity distribution of the concrete structure can be realized.

Description

Technical Field

[0001] The present invention relates to the field of geophysical exploration technology, and in particular to a method and device for evaluating the integrity of a concrete structure based on wave velocity imaging diagnosis. Background Art

[0002] The propagation characteristics of elastic waves in concrete are closely related to the material's internal structure. Its wave velocity parameter, a key physical indicator, reflects the material's mechanical properties and structural integrity. In the field of nondestructive testing, the wave velocity parameter has become a core technical parameter for evaluating concrete's internal properties. Its variation patterns show significant correlations with key quality indicators such as the degree of crack development, compactness, and medium uniformity.

[0003] In the field of concrete structure health monitoring, nondestructive testing technologies based on the propagation characteristics of elastic waves have been widely used. Traditional methods rely primarily on ultrasonic transmission, impact echo, and acoustic emission techniques. These methods indirectly infer the internal state of concrete by measuring parameters such as the propagation time, waveform characteristics, or energy attenuation of elastic waves in the medium. However, the aliasing of external environmental vibration interference and internal damage signals reduces the reliability of the data. Summary of the Invention

[0004] The present invention provides a method and device for assessing the integrity of concrete structures based on wave velocity imaging diagnosis, which is used to overcome the defect of low data credibility caused by signal confusion in the existing concrete assessment methods, and to achieve high-precision real-time monitoring of the wave velocity distribution of concrete structures.

[0005] The present invention provides a method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis, comprising the following steps: obtaining a vibration signal of a concrete structure monitored in real time by a vibration sensor; determining the vibration signal as a target vibration signal when the vibration signal exceeds a preset vibration threshold; identifying the target vibration signal, and determining the first arrival time of the target vibration signal when the target vibration signal is an internal microseismic signal of the concrete structure; performing time inversion positioning on the first arrival time based on a velocity model generated by a previous iteration to obtain the source coordinates of the target vibration signal; constructing a dynamic velocity model based on the first arrival time and the source coordinates; and performing real-time assessment and damage trend analysis on the interior of the concrete structure based on the dynamic velocity model.

[0006] According to a method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis provided by the present invention, after determining the vibration signal as a target vibration signal, the method further includes: identifying the target vibration signal, and when the target vibration signal is a surface disturbance signal of the concrete structure, determining the arrival time of the first arrival wave of the target vibration signal; acquiring audio and video data collected by an audio and video probe; performing multimodal data processing based on the audio and video data to obtain the source coordinates of the target vibration signal; using the source coordinates as a transmitting end and the position of a vibration sensor corresponding to the target vibration signal as a receiving end, and constructing a dynamic velocity model based on the arrival time of the first arrival wave and the source coordinates; and performing real-time assessment and damage trend analysis on the surface of the concrete structure based on the dynamic velocity model.

[0007] According to a method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis provided by the present invention, after determining the arrival time of the first arrival wave of the target vibration signal, the method further includes: performing arrival time inversion positioning on the arrival time of the first arrival wave based on a velocity model generated by a previous iteration to obtain the moment of onset of the target vibration signal; and determining the signal propagation time of the target vibration signal based on the moment of onset of the earthquake and the arrival time of the first arrival wave.

[0008] According to a method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis provided by the present invention, a dynamic velocity model is constructed based on the arrival time of the first arrival wave and the coordinates of the earthquake source, including: using a target algorithm, taking the earthquake source coordinates as the transmitting end, and the vibration sensor position corresponding to the target vibration signal as the receiving end, and constructing a wave velocity model based on the arrival time of the first arrival wave and the coordinates of the earthquake source; obtaining a monitoring vibration signal of a new period, and iteratively optimizing the wave velocity model based on the monitoring vibration signal to obtain a dynamic velocity model.

[0009] According to a concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the present invention, the target algorithm includes: a ray tracing algorithm and a full waveform inversion algorithm.

[0010] According to a method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis provided by the present invention, a plurality of vibration sensors are randomly distributed in three dimensions within the interior of the concrete structure; an acoustic and visual probe is installed on the surface of the concrete structure, the acoustic and visual probe including a spatially distributed camera and a spatially distributed microphone array; the method further includes: obtaining the spatial coordinates of each of the plurality of vibration sensors.

[0011] The present invention also provides a concrete structure integrity assessment device based on wave velocity imaging diagnosis, comprising the following modules: The present invention also provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis as described above is implemented.

[0012] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis as described above is implemented.

[0013] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned methods for assessing the integrity of concrete structures based on wave velocity imaging diagnosis.

[0014] The method and device for assessing the integrity of concrete structures based on wave velocity imaging diagnosis provided by the present invention screen abnormal signals based on vibration thresholds, effectively distinguishing between microseismic events inside the structure and environmental interference; accurately extracting damage characteristic parameters through first-arrival wave arrival time identification and microseismic signal verification; using an iteratively generated velocity model for source inversion positioning, improving the spatial positioning accuracy of internal defects; dynamically updating the velocity model based on source coordinates and first-arrival wave data to overcome the influence of material heterogeneity on wave velocity; and finally realizing real-time visual assessment and evolution trend analysis of internal structural damage based on dynamic wave velocity imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced one by one below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a flow chart of the concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the present invention.

[0017] Figure 2 This is an overall flow chart of the concrete structure integrity assessment based on wave velocity imaging diagnosis provided by the present invention.

[0018] Figure 3 It is a module schematic diagram of the concrete structure integrity assessment device based on wave velocity imaging diagnosis provided by the present invention.

[0019] Figure 4 It is a schematic diagram of the physical structure of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0021] High-quality concrete exhibits a typical uniform distribution of wave velocity characteristics. This material possesses a dense internal structure, with good bond between aggregate and cement paste, and may only contain surface shrinkage cracks or shallow microcracks. Experimental data shows that the longitudinal wave velocity of C30 standard-cured concrete is typically stable between 4000 and 4500 m / s. This velocity characteristic reflects the continuity and uniformity of the stress transfer path within the material, consistent with the propagation laws of elastic waves in continuous media.

[0022] When concrete has quality defects, its wave velocity characteristics will change significantly. Honeycomb defects formed during construction can lead to localized decreases in wave velocity. In such areas, cavities are formed due to the separation of aggregate and slurry, and changes in acoustic impedance cause a decrease in wave velocity. Over long-term service, internal damage such as cracks and interfacial debonding caused by environmental erosion and load fatigue can cause a decrease in wave velocity. This characteristic change in the wave velocity field has become an important criterion for determining the extent of structural damage.

[0023] Existing detection technologies can accurately reconstruct the velocity field distribution within concrete through multi-parameter joint inversion. Ultrasonic tomography (CT) technology utilizes an array sensor network to establish a ray tracing forward model, combined with the algebraic reconstruction algorithm (ART) or the combined iterative reconstruction technique (SIRT), to reconstruct a high-resolution three-dimensional velocity distribution model. Seismic cross-hole CT utilizes elastic wave propagation data between boreholes to obtain the elastic field of the medium through tomography, making it particularly suitable for deep-seated defect detection in large concrete structures. These technological breakthroughs have enabled concrete quality assessment to leapfrog from traditional cross-section testing to three-dimensional, visual diagnosis.

[0024] This technology system offers significant advantages: high detection accuracy; no structural damage during the inspection process, allowing for the acquisition of substantial data within a single inspection cycle; and the ability to visualize inspection results in three dimensions, supporting multi-dimensional data analysis. With the introduction of artificial intelligence algorithms, deep learning-based processing methods have enabled the automated identification and quantitative assessment of defect types, significantly improving detection efficiency and accuracy. Future development will focus on cutting-edge areas such as multi-physics coupling analysis and the development of service performance prediction models, providing technical support for the full lifecycle management of concrete structures.

[0025] Related technology 1, using concrete defect detection network and type change network, can obtain multiple types of sound wave characteristics based on one type of sound wave data, and realize the detection of concrete defects by processing and analyzing the sound wave detection data, which has certain intelligence and data processing capabilities.

[0026] However, the shortcomings of Related Art 1 are that it does not explicitly address the specific application and effectiveness of this method in large-volume concrete inspection, potentially limiting its practical application to structures such as dams and bridges. Furthermore, it relies on a pre-trained network model, whose accuracy and generalization capabilities may be affected by data quality and diversity, and the training process can be complex and time-consuming. Related Art 1 primarily acquires target concrete acoustic wave inspection data and, using a concrete defect detection network and a type change network, infers multiple acoustic wave features based on a single type of acoustic wave data to identify defects. This method focuses on using machine learning to qualitatively detect defects in specific acoustic wave data.

[0027] The present invention uses environmental noise as the earthquake source, collects signals by randomly arranging vibration sensors and surface acoustic and visual sensors, adopts different positioning and identification methods for signals from different sources, uses tomography technology to invert the concrete velocity structure, and constructs a dynamic high-precision velocity model through continuous iteration, focusing more on the quantitative analysis of the internal structure of concrete and the long-term real-time monitoring of the overall state.

[0028] Related technology 2: By arranging monitoring wells in a grid in the monitoring area, collecting time-series response data such as water level, water temperature, flow velocity and direction, and using Bayesian theory to fuse multi-source monitoring data, an interpretation model is constructed; the groundwater migration equation is solved using a continuous linear estimation algorithm, combined with the piping flow-solid coupling model and the parameter sensitivity solution efficient algorithm, the development of reverse erosion piping of the embankment foundation is characterized, the particle loss is calculated and the hydraulic parameter field is updated, ultimately achieving rapid interpretation of monitoring data and real-time online identification of piping.

[0029] However, the shortcoming of the second related technology is that it is mainly applicable to leakage warning of structures such as earth-rock dams and embankments in water conservancy projects. It can quantify the seepage erosion rate and provide early warning of potential risks, but it is not applicable to concrete structures.

[0030] Related technology three, based on the target distance L1 extended from the surface to the interior of the concrete model, obtain the initial model formed after the surface extension, determine multiple target points based on the initial model, determine the core temperature point based on the multiple target points, then, determine multiple target points based on each core temperature point, then, obtain the projection point of each target point on the surface of the concrete model, then, obtain the concrete surface temperature of the multiple projection points, and determine the average temperature of the concrete model based on the surface temperature.

[0031] However, the shortcoming of the third related technology is that it is difficult to effectively correlate the internal performance of the concrete structure by focusing only on temperature.

[0032] In an embodiment of the present invention, microseismic signals are generated when cracks or other damage appear inside the concrete. Simultaneously, activities such as vehicle traffic and people walking on the concrete surface also generate vibration signals. Based on the propagation characteristics of elastic waves in concrete, these signals propagate through the concrete in the form of elastic waves, and different types of signals differ in propagation speed, waveform, and other characteristics. These signals are collected using highly sensitive vibration sensors and acoustic-visual probes, and a dual data link identification mechanism is used to distinguish the signal sources. Finally, tomography or full waveform inversion algorithms are used to invert the signal propagation time and path or waveform, obtaining the wave velocity distribution inside the concrete and thereby constructing a velocity imaging model of the concrete structure.

[0033] Optionally, the concrete structure integrity assessment method based on wave velocity imaging diagnosis in the embodiment of the present application can be executed by a server, or by a terminal device, or jointly by a server and a terminal device, taking the concrete structure integrity assessment method based on wave velocity imaging diagnosis in this embodiment executed by a server as an example.

[0034] Figure 1 Schematic diagram of the flow of the concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the present invention. Figure 1 As shown, the method includes the following: Step 101: Acquire a vibration signal of a concrete structure monitored in real time by a vibration sensor.

[0035] In an embodiment of the present invention, during the construction or operation phase of concrete structures such as dams and bridges, high-precision total stations or RTK (Real-time kinematic) measurement technology are used to randomly deploy high-sensitivity vibration sensors in three dimensions, based on the structural dimensions and monitoring requirements, and accurately obtain the spatial coordinates of each sensor.

[0036] At the same time, an array of acoustic and visual composite sensors was installed at appropriate locations on the concrete structure surface. After the sensors were installed, they were connected to a data collector via dedicated cables. The data collector, signal processing system, and data analysis system were then connected and debugged, and parameters such as the data collector's trigger threshold and monitoring period (1-7 days) were set.

[0037] Step 102: When the vibration signal exceeds a preset vibration threshold, the vibration signal is determined as a target vibration signal.

[0038] In an embodiment of the present invention, a high-sensitivity vibration sensor monitors the vibration signals inside and on the surface of the concrete structure in real time. When the amplitude of the monitoring signal exceeds a preset threshold, the data collector is triggered to start recording the signal collected by the vibration sensor as the target vibration signal.

[0039] At the same time, the audio and video probes are also started synchronously to collect audio and video signals from the concrete surface and record environmental vibration source information.

[0040] Step 103 : Identify the target vibration signal, and when the target vibration signal is an internal microseismic signal of the concrete structure, determine the arrival time of the first arrival wave of the target vibration signal.

[0041] In an embodiment of the present invention, for the signal collected by the vibration sensor, it is first determined whether the signal is an internal microseismic signal generated by the expansion of microcracks inside the concrete. For the microseismic signal generated by the expansion of microcracks inside the concrete, the arrival time of the first arrival wave of the microseismic signal is first extracted.

[0042] In some embodiments, a short-time Fourier transform (STFT) or wavelet transform is performed on the vibration signal to extract the signal's time-frequency distribution characteristics. Microseismic signals typically exhibit sudden high-frequency components (e.g., 50-2000 Hz), while mechanical vibration or ambient noise has a wider frequency band distribution and dispersed energy.

[0043] Calculate signal parameters such as amplitude, main frequency, duration, and energy decay slope. For example, the amplitude of a microseismic signal rises rapidly and then decays exponentially, while the amplitude of impact noise changes gradually.

[0044] Based on a support vector machine (SVM) or random forest classifier, the signal features are input into a pre-trained model (the training set contains known microseismic signals and noise samples), and the signal type probability is output. If the signal is determined to be an internal microseismic signal (with a probability greater than 90%), the first arrival wave extraction process begins.

[0045] In some embodiments, the first arrival wave refers to the first wave that reaches the receiving point during the propagation of a seismic wave or microseismic wave. In concrete structure integrity assessment, the arrival time of the first arrival wave is a key parameter for determining the earthquake source location and performing arrival time inversion positioning.

[0046] The vibration signal is converted to the frequency domain and the first arrival wave is identified by analyzing the spectral characteristics. The multi-scale analysis characteristics of the wavelet transform are utilized to decompose and reconstruct the vibration signal, thereby accurately extracting the arrival time of the first arrival wave. The wavelet transform method is capable of processing non-stationary signals and has good noise suppression capabilities.

[0047] The first arrival time is automatically extracted using algorithms such as the long-short time average ratio (STA / LTA) and the Akaike Information Criterion (AIC). These algorithms can improve the accuracy and efficiency of picking and reduce manual intervention.

[0048] Step 104 : Based on the velocity model generated by the previous iteration, perform arrival time inversion positioning on the first arrival wave to obtain the source coordinates of the target vibration signal.

[0049] In an embodiment of the present invention, for the microseismic signal generated by the expansion of microcracks inside the concrete, the arrival time of the first arrival wave of the microseismic is first extracted, and based on the velocity model generated by the previous iteration (the initial model adopts a uniform model or a velocity model measured by traditional CT), the three-dimensional velocity model arrival time inversion positioning algorithm is then applied to obtain the spatial position of the earthquake source and the time of earthquake occurrence. Finally, the signal propagation time is calculated by combining the arrival time of the first arrival wave and the time of earthquake occurrence.

[0050] Step 105: construct a dynamic velocity model based on the arrival time of the first arrival wave and the earthquake source coordinates.

[0051] In this embodiment of the present invention, the processed valid first-arrival arrival time information and earthquake source coordinate information are transmitted to a data analysis system. The data analysis system integrates all valid data within a set monitoring period and constructs a wave velocity model using a ray tracing-based tomography algorithm or a full waveform inversion algorithm, with the determined earthquake source as the transmitter and the vibration sensor location as the receiver.

[0052] By continuously incorporating data from new cycles into the analysis, iteratively optimizing the wave velocity model, and gradually correcting the concrete medium velocity parameters, a high-precision dynamic velocity model of the concrete structure is constructed, enabling real-time assessment of the health status of the concrete structure and analysis of damage evolution trends.

[0053] Step 106 : Based on the dynamic velocity model, perform real-time assessment and damage trend analysis on the interior of the concrete structure.

[0054] In the embodiment of the present invention, the dynamic velocity model includes velocity information of different regions of the concrete structure, reflecting the material properties and possible damage conditions inside the structure.

[0055] Numerical simulation methods (such as the finite difference method and the finite element method) are used to simulate wave field propagation within concrete structures based on a constructed dynamic velocity model. This simulation allows for intuitive visualization of wave propagation in different regions and at different time points, and for understanding reflection and refraction phenomena when waves encounter different material properties (e.g., normal concrete versus damaged areas).

[0056] In some embodiments, real-time collected signals are used to obtain internal wavefield information about the concrete structure. The wavefield distribution can be used to determine internal changes in the concrete. For example, if the wavefield in a certain area changes over a period of time, this indicates that the area has been disturbed, internal stress has changed, or defects such as cracks have appeared, causing velocity changes. Alternatively, the wave velocity distribution can be used to determine the concrete's properties: locations with low wave velocities indicate poor quality, while locations with high wave velocities indicate good quality.

[0057] The type and extent of damage can be further determined by combining velocity information from different regions in the dynamic velocity model. Generally speaking, a decrease in velocity may correspond to a decrease in material density or a loss of structural integrity. For example, cracks can cause structural integrity to be compromised, increasing energy loss during wave propagation and reducing velocity accordingly.

[0058] Through the above steps of the embodiment of the present invention, abnormal signals are screened based on vibration thresholds to effectively distinguish microseismic events inside the structure from environmental interference; damage characteristic parameters are accurately extracted through first-arrival wave arrival time identification and microseismic signal verification; the iteratively generated velocity model is used to perform source inversion positioning to improve the spatial positioning accuracy of internal defects; the velocity model is dynamically updated by combining the source coordinates and first-arrival wave data to overcome the influence of material heterogeneity on wave velocity; and finally, real-time visual evaluation and evolution trend analysis of internal structural damage are achieved based on dynamic wave velocity images.

[0059] refer to Figure 2 , Figure 2 This is an overall flow chart of the concrete structure integrity assessment based on wave velocity imaging diagnosis provided by the present invention, as detailed in the following embodiments.

[0060] like Figure 2 As shown in the figure, the system process begins with system deployment and initialization, specifically the installation of high-sensitivity vibration sensors and acoustic and visual probes followed by data collection. When the vibration sensor amplitude exceeds the preset threshold or the acoustic and visual composite sensor array collects audio and video signals, the signal processing-dual data link identification phase begins. Based on the judgment result, if it is a microseismic signal, a three-dimensional positioning algorithm is used to calculate the spatial coordinates of the earthquake source and the time of occurrence. If it is a surface disturbance signal, multimodal data processing technology is used to accurately locate the signal position. The process then enters the data analysis and model building phase, ultimately generating a high-precision dynamic velocity model based on ray tracing or full waveform inversion algorithms. After completing real-time assessment and damage trend analysis and combining new cycle data, the process is concluded by determining whether the model needs to be updated.

[0061] According to a method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis provided by the present invention, after determining the vibration signal as a target vibration signal, the method further includes: Identify the target vibration signal and, when the target vibration signal is a surface disturbance signal of a concrete structure, determine the arrival time of the first arrival wave of the target vibration signal; Acquiring audio and video data collected by an audio and video probe; Perform multimodal data processing based on the audio and video data to obtain the source coordinates of the target vibration signal; The earthquake source coordinates are used as the transmitter and the vibration sensor position as the receiver. Based on the arrival time of the first arrival wave and the earthquake source coordinates, a dynamic velocity model is constructed. Based on the dynamic velocity model, the properties of concrete structures are evaluated in real time and damage trends are analyzed.

[0062] In the embodiment of the present invention, for the target vibration signal collected by the vibration sensor, it is first determined whether the signal is a microseismic signal generated by the expansion of microcracks inside the concrete.

[0063] If so, based on the velocity model generated by the previous iteration, the three-dimensional velocity model arrival time inversion positioning algorithm is used to obtain the spatial position of the earthquake source and the time of earthquake occurrence. Finally, the signal propagation time is obtained by the arrival time of the first arrival wave. If it is determined to be an external disturbance signal caused by concrete surface activity, the signal position is accurately identified using multimodal data processing technology in combination with the audio and video data collected by the audio and video probe, the precise coordinates of the signal are obtained, and the precise positioning of the environmental vibration source and the extraction of signal features are completed.

[0064] The processed valid first-arrival wave arrival time information and earthquake source coordinate information are transmitted to the data analysis system. The data analysis system integrates all valid data within the set monitoring cycle and constructs a wave velocity model using a ray tracing-based tomography algorithm or a full waveform inversion algorithm, with the determined earthquake source as the transmitter and the vibration sensor location as the receiver. By continuously incorporating data from new cycles into the analysis, the wave velocity model is iteratively optimized, and the concrete medium velocity parameters are gradually corrected to construct a high-precision dynamic velocity model of the concrete structure, enabling real-time assessment of the concrete structure's health and analysis of damage evolution trends.

[0065] Through the embodiments of the present invention, by identifying the disturbance signal on the surface of the concrete structure and determining the arrival time of its first arrival wave, multimodal processing is performed on the audio and video data collected by the audio and video probe to obtain the source coordinates, and then a dynamic velocity model is constructed with the source as the transmitting end and the sensor as the receiving end, ultimately achieving real-time evaluation and damage trend analysis of the concrete structure surface, accurately locating the source of the surface problem and effectively monitoring the changes in surface damage.

[0066] According to a method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis provided by the present invention, after determining the arrival time of the first arrival wave of the target vibration signal, the method further includes: Based on the velocity model generated by the previous iteration, the arrival time of the first arrival wave is inverted and located to obtain the onset time of the target vibration signal; Based on the earthquake occurrence time and the arrival time of the first arrival wave, the signal propagation time of the target vibration signal is determined.

[0067] In an embodiment of the present invention, the three-dimensional dynamic velocity model data generated by the previous iteration is used to describe the wave velocity distribution in different regions inside the concrete structure. The first arrival time data of the verified target microseismic signal are extracted from multiple vibration sensors.

[0068] According to the geometric distribution of the sensor array, the initial location of the earthquake source is set as the center point of the sensor coverage area, or it is estimated based on the statistical location of historical microseismic events.

[0069] Take the earliest first arrival time of all sensors, subtract the propagation time estimated based on the average wave velocity (such as the theoretical travel time of the nearest sensor), and use it as the initial value of the earthquake occurrence time.

[0070] Using the current velocity model, the theoretical propagation time from the earthquake source to each sensor is calculated using ray tracing algorithms (such as the shortest path method) or numerical simulations (such as the finite difference method). The theoretical propagation time is compared with the actual first arrival time. Using a least-squares optimization algorithm, the earthquake source location and earthquake onset time are adjusted simultaneously, gradually narrowing the error between the predicted and measured values. When the position correction is less than a set threshold (such as 0.01 meters) and the time correction is less than the time accuracy (such as 0.1 milliseconds), convergence is determined, and the final earthquake source coordinates and earthquake onset time are output.

[0071] Based on the inverted earthquake occurrence time and the first arrival time of each sensor, the propagation time of each sensor is directly calculated.

[0072] Through the embodiments of the present invention, the arrival time of the first arrival wave is inverted and located based on the velocity model generated by the previous iteration to obtain the target vibration signal earthquake moment, and then the earthquake moment and the first arrival wave arrival time are combined to determine the signal propagation time. This process can accurately calculate the propagation time of the vibration signal in the concrete structure, providing key time parameters for subsequent location of the earthquake source, analysis of the internal condition of the structure, and evaluation of the structural integrity.

[0073] According to the present invention, a method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis is provided. A dynamic velocity model is constructed based on the arrival time of the first arrival wave and the coordinates of the earthquake source, including: Through the target algorithm, the earthquake source coordinates are used as the transmitter, and the vibration sensor position corresponding to the target vibration signal is used as the receiver. Based on the arrival time of the first wave and the earthquake source coordinates, a wave velocity model is constructed. The monitoring vibration signal of the new period is obtained, and the wave velocity model is iteratively optimized based on the monitoring vibration signal to obtain a dynamic velocity model.

[0074] Among them, the target algorithms include: ray tracing algorithm and full waveform inversion algorithm.

[0075] In this embodiment, a ray-tracing-based tomography algorithm or full waveform inversion algorithm is used to construct a velocity model, with the determined earthquake source as the transmitter and the vibration sensor location as the receiver. By continuously incorporating data from new cycles into the analysis, the velocity model is iteratively optimized, gradually correcting the concrete medium's velocity parameters to construct a high-precision dynamic velocity model of the concrete structure.

[0076] The ray tracing-based tomography algorithm assumes that the waves propagate along a ray path connecting the source (transmitter) and the sensor (receiver). Specifically: Discretize the concrete structure area into a grid (such as pixels or voxels). Assign an initial wave velocity estimate to each grid cell (which can be a uniform value or set based on experience). Use ray tracing techniques (such as the shortest path method, the curved ray method, etc.) to calculate the theoretical propagation time of each source-sensor ray under the current wave velocity model. Compare the time residual between the theoretical propagation time and the actual measured first arrival time. Use an inversion algorithm (such as the least squares method, the algebraic reconstruction technique ART, the joint iterative reconstruction technique SIRT, etc.) to reversely infer and update the wave velocity value of the grid cell based on the time residuals of all rays, with the goal of making the theoretical time as close as possible to the measured time. Iterate ray tracing and inversion updates until the time residual converges to an acceptable range or reaches the preset number of iterations, and obtain the initial wave velocity distribution model.

[0077] The full waveform inversion algorithm utilizes not only the arrival time of the first arrival wave, but also the information contained in the entire received vibration signal waveform (amplitude, phase, frequency components, etc.). It requires higher model accuracy and is more computationally intensive. Specifically: A discretized model and initial wave velocity estimation are also required. Using a wave equation numerical simulator (such as the finite difference method or the finite element method), based on the current wave velocity model, a complete theoretical waveform that should be received by each sensor location is simulated and calculated. The difference between the simulated theoretical waveform and the actual monitored vibration signal waveform is compared (usually measured by the norm of the waveform data difference, such as the L2 norm). Using an optimization algorithm (such as gradient descent, conjugate gradient method, or quasi-Newton method), the gradient (i.e., sensitivity) of the waveform difference relative to the model parameters (grid wave velocity) is calculated. The wave velocity model is then updated accordingly, aiming to ensure that the simulated waveform matches the actual waveform as closely as possible. Forward modeling, difference calculation, gradient calculation, and model update are iteratively performed until the waveform match meets the requirements or convergence is achieved. The resulting initial wave velocity distribution model is theoretically more accurate than ray tomography, especially for complex structures. An initial wave velocity model is output that approximates the wave velocity distribution within the concrete structure during the current monitoring period.

[0078] It should be noted that the state of concrete structures (such as the development of microcracks, changes in humidity, and changes in stress state) can change over time, causing changes in the internal wave velocity distribution. The static initial model cannot reflect these dynamic changes. Therefore, it is necessary to continuously introduce new monitoring data to update the model.

[0079] New-cycle monitoring vibration signals are new vibration signals collected during subsequent monitoring cycles (e.g., days, weeks, or months later). These signals also include the coordinates of the new source event (artificially excited or naturally occurring) (if a natural source is used, its location is required), the arrival time of the first arrival of the new source event at each sensor (for ray tomography), or the complete waveform data (for full waveform inversion).

[0080] The source coordinates, sensor coordinates, and first arrival time (or complete waveform) collected in the new period are used as new input data; For ray tomography, the velocity model obtained in the previous step (the initial model or the model optimized in the previous step) is used as the initial model for this inversion. Then, during the ray tracing and inversion process, the velocity model is updated using new data (possibly combined with some historical data). The time residuals introduced by the new data drive the model update to better reflect the current situation.

[0081] For full waveform inversion, the previous model is used as the initial model. Using newly acquired complete waveform data, the forward modeling, waveform difference calculation, gradient calculation, and model update process are repeated. The richer information contained in the new waveform data helps to more precisely characterize the current structural state.

[0082] As more and more monitoring period data is incorporated into the inversion, the model is constantly constrained and modified by new observations. Not only does the model reflect the current state, but its accuracy and resolution also gradually improve with the accumulation of data, ultimately forming a highly accurate dynamic velocity model that captures the temporal changes in wave velocity (reflecting material properties) within the concrete structure.

[0083] Through the embodiments of the present invention, the dynamic velocity model will be automatically updated and corrected as the structural state changes (reflected by new monitoring data) to reflect the latest wave velocity conditions inside the structure.

[0084] According to a concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the present invention, a plurality of vibration sensors are randomly distributed in three dimensions inside the concrete structure; an acoustic and visual probe is installed on the surface of the concrete structure, and the acoustic and visual probe includes a spatially distributed camera and a spatially distributed microphone array; The above method further includes: The spatial coordinates of each vibration sensor among the plurality of vibration sensors are obtained.

[0085] In the embodiment of the present invention, the wave velocity imaging system is composed of four parts: a sensor array, a data acquisition system, a signal processing system, and a data analysis system.

[0086] The sensor array consists of highly sensitive vibration sensors and acoustic and visual probes. The highly sensitive vibration sensors have a range of 0.1-1g and are randomly distributed in a three-dimensional pattern throughout large concrete structures (such as dams and bridges). The number of sensors depends on the structure size and the required monitoring accuracy, and each sensor is connected to a data collector. The acoustic and visual probes, consisting of a high-definition camera and microphone array, are placed on the surface of the concrete structure to collect signals and locate vibration sources in the surface environment. The camera and microphone array are installed at a specific spacing and angle to ensure coverage and positioning accuracy.

[0087] The data acquisition system primarily consists of a data collector and dedicated cables. The data collector has multiple data acquisition channels, each corresponding to a vibration sensor. The dedicated cables transmit the signals collected by the vibration sensors to the data collector. Simultaneously, the data collector is connected to the acoustic and visual probes for trigger synchronization.

[0088] The signal processing system is a computer-based hardware and software system equipped with a dual data link identification algorithm program and data processing software, which is used to classify and process the collected signals and extract features.

[0089] The data analysis system is also computer-based and has a built-in ray tracing-based tomography algorithm or full waveform inversion algorithm program, which is used to perform time inversion or waveform inversion of effective signals and construct a velocity model.

[0090] In this embodiment of the present invention, a highly sensitive vibration sensor is connected to the corresponding channel of a data acquisition device via a dedicated cable, transmitting the collected vibration signals to the data acquisition device in real time. An acoustic and visual probe is also connected to the data acquisition device via a data cable, enabling data transmission and trigger synchronization. The data acquisition device transmits all collected signals to a signal processing system via a network or data cable. After processing the signals, the signal processing system transmits the valid data to a data analysis system, which performs arrival time or waveform inversion and constructs a velocity model.

[0091] An example of practical application of the concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the present invention is described below.

[0092] This invention uses environmental noise excitation to construct a wave velocity imaging system for large-volume concrete structures, suitable for health monitoring of critical infrastructure such as dams and bridges. The system employs a three-dimensional, randomized arrangement of high-sensitivity vibration sensors (with a range of 0.1-1g acceleration) within the concrete structure. This system uses a high-precision total station or RTK to obtain the spatial coordinates of the sensors, creating a monitoring network. The vibration signals collected by the sensors are transmitted via dedicated cables to a synchronous data acquisition system. This system utilizes a triggered acquisition mechanism, initiating data recording when the amplitude of the monitored signal exceeds a preset threshold.

[0093] The signal processing link adopts a dual data link identification mechanism: for the microseismic signals generated by the expansion of microcracks inside the concrete, the arrival time of the microseismic first wave is first extracted, and based on the velocity model generated by the previous iteration (the initial model adopts a uniform model or a velocity model measured by traditional CT), the three-dimensional velocity model arrival time inversion positioning algorithm is then used to obtain the spatial position of the earthquake source and the time of earthquake occurrence. Finally, the signal propagation time is calculated by combining the arrival time of the first wave and the time of earthquake occurrence. For external disturbances caused by activities on the concrete surface (such as vehicle passage and people walking), multimodal data acquisition is carried out using an acoustic and visual composite sensor probe (composed of a high-definition camera and a microphone array), the signal position is accurately identified and the precise coordinates of the signal are obtained. Combined with synchronous triggering technology, precise positioning of the environmental vibration source and signal feature extraction are achieved.

[0094] During the data processing phase, an observation system, built with the seismic source as the transmitter and sensors as the receiver, integrates information such as the arrival time and waveform amplitude of effective first arrivals from periodic monitoring data (the period can be set to 1-7 days). A velocity model is constructed using a ray tracing-based tomography algorithm or a full waveform inversion algorithm. Through iterative optimization of multi-period data, the concrete medium velocity parameters are continuously corrected, gradually constructing a high-precision dynamic velocity image model of the concrete structure. This model not only promptly reflects the elastic wave propagation characteristics within the concrete but also effectively identifies the evolution of structural damage by comparing and analyzing the changes in the velocity model across each period.

[0095] This invention breaks through the spatial and temporal limitations of traditional artificial seismic source layout and acquisition, fully utilizes environmental vibration as an excitation source, combines multi-source data fusion with a dynamic iterative optimization algorithm, and realizes high-precision real-time monitoring of the wave velocity distribution of concrete structures, providing reliable data support for engineering structure health diagnosis.

[0096] The following describes the concrete structure integrity assessment device based on wave velocity imaging diagnosis provided by the present invention. The concrete structure integrity assessment device based on wave velocity imaging diagnosis described below and the concrete structure integrity assessment method based on wave velocity imaging diagnosis described above can be referenced to each other.

[0097] refer to Figure 3 , Figure 3 It is a module schematic diagram of the concrete structure integrity assessment device based on wave velocity imaging diagnosis provided by the present invention.

[0098] An acquisition module 301 is used to acquire a vibration signal of the concrete structure monitored in real time by a vibration sensor; A determination module 302 is configured to determine the vibration signal as a target vibration signal when the vibration signal exceeds a preset vibration threshold; The identification module 303 is used to identify the target vibration signal and determine the arrival time of the first arrival wave of the target vibration signal when the target vibration signal is an internal microseismic signal of the concrete structure; The positioning module 304 is used to perform time inversion positioning of the first arrival wave based on the velocity model generated by the previous iteration to obtain the source coordinates of the target vibration signal; A construction module 305 is used to construct a dynamic velocity model based on the arrival time of the first arrival wave and the coordinates of the earthquake source; The evaluation module 306 is used to perform real-time evaluation and damage trend analysis on the interior of the concrete structure based on a dynamic velocity model.

[0099] Specifically, the above-mentioned concrete structure integrity assessment device based on wave velocity imaging diagnosis provided by the present invention can implement all the method steps implemented in the above-mentioned concrete structure integrity assessment method embodiment based on wave velocity imaging diagnosis, and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those of the method embodiment will not be described in detail here.

[0100] Figure 4 This is a schematic diagram of the physical structure of the electronic device provided by the present invention, such as Figure 4 As shown, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communications bus 440, wherein the processor 410, the communications interface 420, and the memory 430 communicate with each other via the communications bus 440. The processor 410 may call logic instructions in the memory 430 to execute a method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis. The method includes: acquiring a vibration signal of a concrete structure monitored in real time by a vibration sensor; determining the vibration signal as a target vibration signal when the vibration signal exceeds a preset vibration threshold; identifying the target vibration signal and, if the target vibration signal is an internal microseismic signal of the concrete structure, determining the arrival time of the first arrival of the target vibration signal; performing arrival time inversion on the arrival time of the first arrival based on a velocity model generated by a previous iteration to obtain the hypocenter coordinates of the target vibration signal; constructing a dynamic velocity model based on the arrival time of the first arrival and the hypocenter coordinates; and performing real-time assessment and damage trend analysis on the interior of the concrete structure based on the dynamic velocity model.

[0101] Furthermore, the logic instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0102] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the above methods, the method including: obtaining a vibration signal of the concrete structure monitored in real time by a vibration sensor; when the vibration signal exceeds a preset vibration threshold, determining the vibration signal as a target vibration signal; identifying the target vibration signal, and when the target vibration signal is an internal microseismic signal of the concrete structure, determining the first arrival time of the target vibration signal; based on the velocity model generated by the previous iteration, performing arrival time inversion positioning on the first arrival time to obtain the source coordinates of the target vibration signal; constructing a dynamic velocity model based on the first arrival time and the source coordinates; based on the dynamic velocity model, performing real-time assessment and damage trend analysis on the interior of the concrete structure.

[0103] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the concrete structure integrity assessment method based on wave velocity imaging diagnosis provided by the above-mentioned methods, the method comprising: obtaining a vibration signal of the concrete structure monitored in real time by a vibration sensor; when the vibration signal exceeds a preset vibration threshold, determining the vibration signal as a target vibration signal; identifying the target vibration signal, and when the target vibration signal is an internal microseismic signal of the concrete structure, determining the first arrival time of the target vibration signal; based on the velocity model generated by the previous iteration, performing time inversion positioning on the first arrival time to obtain the source coordinates of the target vibration signal; constructing a dynamic velocity model based on the first arrival time and the source coordinates; and performing real-time assessment and damage trend analysis on the interior of the concrete structure based on the dynamic velocity model.

[0104] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0105] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis, characterized in that: include: Acquire the vibration signal of the concrete structure monitored in real time by the vibration sensor; When the vibration signal exceeds a preset vibration threshold, determining the vibration signal as a target vibration signal; Identifying the target vibration signal, and determining the first arrival time of the target vibration signal when the target vibration signal is an internal microseismic signal of the concrete structure; Based on the velocity model generated by the previous iteration, the arrival time of the first arrival wave is inverted and located to obtain the source coordinates of the target vibration signal; constructing a dynamic velocity model based on the arrival time of the first arrival wave and the earthquake source coordinates; Based on the dynamic velocity model, real-time evaluation and damage trend analysis are performed on the interior of the concrete structure.

2. The method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis according to claim 1 is characterized in that: After determining the vibration signal as a target vibration signal, the method further includes: identifying the target vibration signal, and determining the arrival time of the first arrival wave of the target vibration signal when the target vibration signal is a surface disturbance signal of the concrete structure; Acquiring audio and video data collected by an audio and video probe; Performing multimodal data processing based on the audio and video data to obtain the source coordinates of the target vibration signal; Taking the earthquake source coordinates as the transmitting end and the vibration sensor position corresponding to the target vibration signal as the receiving end, a dynamic velocity model is constructed based on the arrival time of the first arrival wave and the earthquake source coordinates; Based on the dynamic velocity model, real-time evaluation and damage trend analysis are performed on the surface of the concrete structure.

3. The method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis according to claim 1, characterized in that: After determining the arrival time of the first arrival wave of the target vibration signal, the method further includes: Based on the velocity model generated by the previous iteration, the arrival time of the first arrival wave is inverted and located to obtain the onset time of the target vibration signal; Based on the earthquake occurrence moment and the arrival time of the first arrival wave, the signal propagation time of the target vibration signal is determined.

4. The method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis according to claim 1, characterized in that: The constructing of a dynamic velocity model based on the first arrival wave arrival time and the earthquake source coordinates includes: By using a target algorithm, the earthquake source coordinates are used as a transmitter, the vibration sensor position corresponding to the target vibration signal is used as a receiver, and a wave velocity model is constructed based on the arrival time of the first arrival wave and the earthquake source coordinates; A monitoring vibration signal of a new period is acquired, and based on the monitoring vibration signal, the wave velocity model is iteratively optimized to obtain a dynamic velocity model.

5. The method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis according to claim 4 is characterized in that: The target algorithms include: ray tracing algorithm and full waveform inversion algorithm.

6. The method for assessing the integrity of concrete structures based on wave velocity imaging diagnosis according to claim 1, characterized in that: A plurality of vibration sensors are randomly distributed in three dimensions inside the concrete structure; an audio and visual probe is installed on the surface of the concrete structure, and the audio and visual probe includes a spatially distributed camera and a spatially distributed microphone array; The method further comprises: The spatial coordinates of each vibration sensor in the plurality of vibration sensors are acquired.

7. A concrete structure integrity assessment device based on wave velocity imaging diagnosis, characterized in that: include: An acquisition module, used for acquiring a vibration signal of the concrete structure monitored in real time by a vibration sensor; a determination module, configured to determine the vibration signal as a target vibration signal when the vibration signal exceeds a preset vibration threshold; an identification module, configured to identify the target vibration signal and, when the target vibration signal is an internal microseismic signal of the concrete structure, determine the arrival time of the first arrival wave of the target vibration signal; A positioning module is used to perform time inversion positioning on the arrival time of the first arrival wave based on the velocity model generated by the previous iteration to obtain the source coordinates of the target vibration signal; A construction module, configured to construct a dynamic velocity model based on the arrival time of the first arrival wave and the earthquake source coordinates; An evaluation module is used to perform real-time evaluation and damage trend analysis on the interior of the concrete structure based on the dynamic velocity model.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis according to any one of claims 1 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis according to any one of claims 1 to 6 is implemented.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method for assessing the integrity of a concrete structure based on wave velocity imaging diagnosis according to any one of claims 1 to 6 is implemented.

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